[PATCH v1 2/2] i3c: master: Add Nuvoton npcm845 i3c master driver

Frank Li Frank.li at nxp.com
Sat Aug 3 02:16:59 AEST 2024


On Thu, Aug 01, 2024 at 03:19:46PM +0800, Stanley Chu wrote:
> Add support for the Nuvoton npcm845 i3c controller which
> implements I3C master functionality as defined in the MIPI
> Alliance Specification for I3C, Version 1.0.
>
> The master role is supported in SDR mode only. IBI and Hot-join
> requsts are supported.
>
> Signed-off-by: Stanley Chu <yschu at nuvoton.com>
> Signed-off-by: James Chiang <cpchiang1 at nuvoton.com>
> ---
>  MAINTAINERS                             |    7 +
>  drivers/i3c/master/Kconfig              |   14 +
>  drivers/i3c/master/Makefile             |    1 +
>  drivers/i3c/master/npcm845-i3c-master.c | 2364 +++++++++++++++++++++++
>  4 files changed, 2386 insertions(+)
>  create mode 100644 drivers/i3c/master/npcm845-i3c-master.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 42decde38320..2d30b6e418d8 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2670,6 +2670,13 @@ F:	Documentation/userspace-api/media/drivers/npcm-video.rst
>  F:	drivers/media/platform/nuvoton/
>  F:	include/uapi/linux/npcm-video.h
>
> +ARM/NUVOTON NPCM845 I3C MASTER DRIVER
> +M:	Stanley Chu <yschu at nuvoton.com>
> +M:	James Chiang <cpchiang1 at nuvoton.com>
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/i3c/nuvoton,i3c-master.yaml
> +F:	drivers/i3c/master/npcm845-i3c-master.c
> +
>  ARM/NUVOTON WPCM450 ARCHITECTURE
>  M:	Jonathan Neuschäfer <j.neuschaefer at gmx.net>
>  L:	openbmc at lists.ozlabs.org (moderated for non-subscribers)
> diff --git a/drivers/i3c/master/Kconfig b/drivers/i3c/master/Kconfig
> index 90dee3ec5520..a71d504d4744 100644
> --- a/drivers/i3c/master/Kconfig
> +++ b/drivers/i3c/master/Kconfig
> @@ -44,6 +44,20 @@ config SVC_I3C_MASTER
>  	help
>  	  Support for Silvaco I3C Dual-Role Master Controller.
>
> +config NPCM845_I3C_MASTER
> +	tristate "Nuvoton NPCM845 I3C master driver"
> +	depends on I3C
> +	depends on HAS_IOMEM
> +	depends on ARCH_NPCM || COMPILE_TEST
> +	help
> +	  Support for Nuvoton NPCM845 I3C Master Controller.
> +
> +	  This hardware is an instance of the SVC I3C controller; this
> +	  driver adds platform specific support for NPCM845 hardware.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called npcm845-i3c-master.
> +
>  config MIPI_I3C_HCI
>  	tristate "MIPI I3C Host Controller Interface driver (EXPERIMENTAL)"
>  	depends on I3C
> diff --git a/drivers/i3c/master/Makefile b/drivers/i3c/master/Makefile
> index 3e97960160bc..3ed55113190a 100644
> --- a/drivers/i3c/master/Makefile
> +++ b/drivers/i3c/master/Makefile
> @@ -3,4 +3,5 @@ obj-$(CONFIG_CDNS_I3C_MASTER)		+= i3c-master-cdns.o
>  obj-$(CONFIG_DW_I3C_MASTER)		+= dw-i3c-master.o
>  obj-$(CONFIG_AST2600_I3C_MASTER)	+= ast2600-i3c-master.o
>  obj-$(CONFIG_SVC_I3C_MASTER)		+= svc-i3c-master.o
> +obj-$(CONFIG_NPCM845_I3C_MASTER)	+= npcm845-i3c-master.o
>  obj-$(CONFIG_MIPI_I3C_HCI)		+= mipi-i3c-hci/
> diff --git a/drivers/i3c/master/npcm845-i3c-master.c b/drivers/i3c/master/npcm845-i3c-master.c
> new file mode 100644
> index 000000000000..19672fdbe2b8
> --- /dev/null
> +++ b/drivers/i3c/master/npcm845-i3c-master.c
> @@ -0,0 +1,2364 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Nuvoton NPCM845 I3C master driver
> + *
> + * Copyright (C) 2024 Nuvoton Technology Corp.
> + * Based on the work from svc i3c master driver and add platform
> + * specific support for the NPCM845 hardware.
> + */
> +
> +#include <linux/bitfield.h>
> +#include <linux/clk.h>
> +#include <linux/completion.h>
> +#include <linux/debugfs.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/errno.h>
> +#include <linux/interrupt.h>
> +#include <linux/iopoll.h>
> +#include <linux/list.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/of.h>
> +#include <linux/reset.h>
> +#include <linux/i3c/master.h>
> +#include <linux/pinctrl/consumer.h>
> +#include <linux/platform_device.h>

Please sort include files

> +
> +/* Master Mode Registers */
> +#define NPCM_I3C_MCONFIG      0x000
> +#define   NPCM_I3C_MCONFIG_MASTER_EN BIT(0)
> +#define   NPCM_I3C_MCONFIG_DISTO(x) FIELD_PREP(BIT(3), (x))
> +#define   NPCM_I3C_MCONFIG_HKEEP(x) FIELD_PREP(GENMASK(5, 4), (x))
> +#define   NPCM_I3C_MCONFIG_ODSTOP(x) FIELD_PREP(BIT(6), (x))
> +#define   NPCM_I3C_MCONFIG_PPBAUD(x) FIELD_PREP(GENMASK(11, 8), (x))
> +#define   NPCM_I3C_MCONFIG_PPLOW(x) FIELD_PREP(GENMASK(15, 12), (x))
> +#define   NPCM_I3C_MCONFIG_ODBAUD(x) FIELD_PREP(GENMASK(23, 16), (x))
> +#define   NPCM_I3C_MCONFIG_ODHPP(x) FIELD_PREP(BIT(24), (x))
> +#define   NPCM_I3C_MCONFIG_SKEW(x) FIELD_PREP(GENMASK(27, 25), (x))
> +#define   NPCM_I3C_MCONFIG_SKEW_MASK GENMASK(27, 25)
> +#define   NPCM_I3C_MCONFIG_I2CBAUD(x) FIELD_PREP(GENMASK(31, 28), (x))
> +
> +#define NPCM_I3C_MCTRL        0x084
> +#define   NPCM_I3C_MCTRL_REQUEST_MASK GENMASK(2, 0)
> +#define   NPCM_I3C_MCTRL_REQUEST(x) FIELD_GET(GENMASK(2, 0), (x))
> +#define   NPCM_I3C_MCTRL_REQUEST_NONE 0
> +#define   NPCM_I3C_MCTRL_REQUEST_START_ADDR 1
> +#define   NPCM_I3C_MCTRL_REQUEST_STOP 2
> +#define   NPCM_I3C_MCTRL_REQUEST_IBI_ACKNACK 3
> +#define   NPCM_I3C_MCTRL_REQUEST_PROC_DAA 4
> +#define   NPCM_I3C_MCTRL_REQUEST_FORCE_EXIT 6
> +#define   NPCM_I3C_MCTRL_REQUEST_AUTO_IBI 7
> +#define   NPCM_I3C_MCTRL_TYPE_I3C 0
> +#define   NPCM_I3C_MCTRL_TYPE_I2C BIT(4)
> +#define   NPCM_I3C_MCTRL_IBIRESP_AUTO 0
> +#define   NPCM_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE 0
> +#define   NPCM_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE BIT(7)
> +#define   NPCM_I3C_MCTRL_IBIRESP_NACK BIT(6)
> +#define   NPCM_I3C_MCTRL_IBIRESP_MANUAL GENMASK(7, 6)
> +#define   NPCM_I3C_MCTRL_DIR(x) FIELD_PREP(BIT(8), (x))
> +#define   NPCM_I3C_MCTRL_DIR_WRITE 0
> +#define   NPCM_I3C_MCTRL_DIR_READ 1
> +#define   NPCM_I3C_MCTRL_ADDR(x) FIELD_PREP(GENMASK(15, 9), (x))
> +#define   NPCM_I3C_MCTRL_RDTERM(x) FIELD_PREP(GENMASK(23, 16), (x))
> +
> +#define NPCM_I3C_MSTATUS      0x088
> +#define   NPCM_I3C_MSTATUS_STATE(x) FIELD_GET(GENMASK(2, 0), (x))
> +#define   NPCM_I3C_MSTATUS_STATE_DAA(x) (NPCM_I3C_MSTATUS_STATE(x) == 5)
> +#define   NPCM_I3C_MSTATUS_STATE_IDLE(x) (NPCM_I3C_MSTATUS_STATE(x) == 0)
> +#define   NPCM_I3C_MSTATUS_STATE_SLVREQ(x) (NPCM_I3C_MSTATUS_STATE(x) == 1)
> +#define   NPCM_I3C_MSTATUS_STATE_IBIACK(x) (NPCM_I3C_MSTATUS_STATE(x) == 6)
> +#define   NPCM_I3C_MSTATUS_BETWEEN(x) FIELD_GET(BIT(4), (x))
> +#define   NPCM_I3C_MSTATUS_NACKED(x) FIELD_GET(BIT(5), (x))
> +#define   NPCM_I3C_MSTATUS_IBITYPE(x) FIELD_GET(GENMASK(7, 6), (x))
> +#define   NPCM_I3C_MSTATUS_IBITYPE_IBI 1
> +#define   NPCM_I3C_MSTATUS_IBITYPE_MASTER_REQUEST 2
> +#define   NPCM_I3C_MSTATUS_IBITYPE_HOT_JOIN 3
> +#define   NPCM_I3C_MINT_SLVSTART BIT(8)
> +#define   NPCM_I3C_MINT_MCTRLDONE BIT(9)
> +#define   NPCM_I3C_MINT_COMPLETE BIT(10)
> +#define   NPCM_I3C_MINT_RXPEND BIT(11)
> +#define   NPCM_I3C_MINT_TXNOTFULL BIT(12)
> +#define   NPCM_I3C_MINT_IBIWON BIT(13)
> +#define   NPCM_I3C_MINT_ERRWARN BIT(15)
> +#define   NPCM_I3C_MSTATUS_SLVSTART(x) FIELD_GET(NPCM_I3C_MINT_SLVSTART, (x))
> +#define   NPCM_I3C_MSTATUS_MCTRLDONE(x) FIELD_GET(NPCM_I3C_MINT_MCTRLDONE, (x))
> +#define   NPCM_I3C_MSTATUS_COMPLETE(x) FIELD_GET(NPCM_I3C_MINT_COMPLETE, (x))
> +#define   NPCM_I3C_MSTATUS_RXPEND(x) FIELD_GET(NPCM_I3C_MINT_RXPEND, (x))
> +#define   NPCM_I3C_MSTATUS_TXNOTFULL(x) FIELD_GET(NPCM_I3C_MINT_TXNOTFULL, (x))
> +#define   NPCM_I3C_MSTATUS_IBIWON(x) FIELD_GET(NPCM_I3C_MINT_IBIWON, (x))
> +#define   NPCM_I3C_MSTATUS_ERRWARN(x) FIELD_GET(NPCM_I3C_MINT_ERRWARN, (x))
> +#define   NPCM_I3C_MSTATUS_IBIADDR(x) FIELD_GET(GENMASK(30, 24), (x))
> +
> +#define NPCM_I3C_IBIRULES     0x08C
> +#define   NPCM_I3C_IBIRULES_ADDR(slot, addr) FIELD_PREP(GENMASK(29, 0), \
> +						       ((addr) & 0x3F) << ((slot) * 6))
> +#define   NPCM_I3C_IBIRULES_ADDRS 5
> +#define   NPCM_I3C_IBIRULES_MSB0 BIT(30)
> +#define   NPCM_I3C_IBIRULES_NOBYTE BIT(31)
> +#define   NPCM_I3C_IBIRULES_MANDBYTE 0
> +#define NPCM_I3C_MINTSET      0x090
> +#define NPCM_I3C_MINTCLR      0x094
> +#define NPCM_I3C_MINTMASKED   0x098
> +#define NPCM_I3C_MERRWARN     0x09C
> +#define   NPCM_I3C_MERRWARN_NACK(x) FIELD_GET(BIT(2), (x))
> +#define   NPCM_I3C_MERRWARN_TIMEOUT BIT(20)
> +#define   NPCM_I3C_MERRWARN_HCRC(x) FIELD_GET(BIT(10), (x))
> +#define NPCM_I3C_MDMACTRL     0x0A0
> +#define   NPCM_I3C_MDMACTRL_DMAFB(x) FIELD_PREP(GENMASK(1, 0), (x))
> +#define   NPCM_I3C_MDMACTRL_DMATB(x) FIELD_PREP(GENMASK(3, 2), (x))
> +#define   NPCM_I3C_MDMACTRL_DMAWIDTH(x) FIELD_PREP(GENMASK(5, 4), (x))
> +#define NPCM_I3C_MDATACTRL    0x0AC
> +#define   NPCM_I3C_MDATACTRL_FLUSHTB BIT(0)
> +#define   NPCM_I3C_MDATACTRL_FLUSHRB BIT(1)
> +#define   NPCM_I3C_MDATACTRL_UNLOCK_TRIG BIT(3)
> +#define   NPCM_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4)
> +#define   NPCM_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0
> +#define   NPCM_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x))
> +#define   NPCM_I3C_MDATACTRL_TXCOUNT(x) FIELD_GET(GENMASK(20, 16), (x))
> +#define   NPCM_I3C_MDATACTRL_TXFULL BIT(30)
> +#define   NPCM_I3C_MDATACTRL_RXEMPTY BIT(31)
> +
> +#define NPCM_I3C_MWDATAB      0x0B0
> +#define   NPCM_I3C_MWDATAB_END BIT(8)
> +
> +#define NPCM_I3C_MWDATABE     0x0B4
> +#define NPCM_I3C_MWDATAH      0x0B8
> +#define NPCM_I3C_MWDATAHE     0x0BC
> +#define NPCM_I3C_MRDATAB      0x0C0
> +#define NPCM_I3C_MRDATAH      0x0C8
> +
> +#define NPCM_I3C_MDYNADDR     0x0E4
> +#define   NPCM_MDYNADDR_VALID BIT(0)
> +#define   NPCM_MDYNADDR_ADDR(x) FIELD_PREP(GENMASK(7, 1), (x))
> +
> +#define NPCM_I3C_PARTNO       0x06C
> +#define NPCM_I3C_VENDORID     0x074
> +#define   NPCM_I3C_VENDORID_VID(x) FIELD_GET(GENMASK(14, 0), (x))
> +
> +#define NPCM_I3C_MAX_DEVS 32
> +#define NPCM_I3C_PM_TIMEOUT_MS 1000

Above register layer out is very similar with svc-i3c-master.c, I suppose
you can reuse it and just add DMA support port.

Frank

> +
> +/* This parameter depends on the implementation and may be tuned */
> +#define NPCM_I3C_FIFO_SIZE 16
> +#define NPCM_I3C_MAX_IBI_PAYLOAD_SIZE 8
> +#define NPCM_I3C_MAX_RDTERM 255
> +#define NPCM_I3C_MAX_PPBAUD 15
> +#define NPCM_I3C_MAX_PPLOW 15
> +#define NPCM_I3C_MAX_ODBAUD 255
> +#define NPCM_I3C_MAX_I2CBAUD 15
> +#define I3C_SCL_PP_PERIOD_NS_MIN 40
> +#define I3C_SCL_OD_LOW_PERIOD_NS_MIN 200
> +
> +/* DMA definitions */
> +#define MAX_DMA_COUNT		1024
> +#define DMA_CH_TX		0
> +#define DMA_CH_RX		1
> +#define NPCM_GDMA_CTL(n)	(n * 0x20 + 0x00)
> +#define   NPCM_GDMA_CTL_GDMAMS(x) FIELD_PREP(GENMASK(3, 2), (x))
> +#define   NPCM_GDMA_CTL_TWS(x) FIELD_PREP(GENMASK(13, 12), (x))
> +#define   NPCM_GDMA_CTL_GDMAEN	BIT(0)
> +#define   NPCM_GDMA_CTL_DAFIX	BIT(6)
> +#define   NPCM_GDMA_CTL_SAFIX	BIT(7)
> +#define   NPCM_GDMA_CTL_SIEN	BIT(8)
> +#define   NPCM_GDMA_CTL_DM	BIT(15)
> +#define   NPCM_GDMA_CTL_TC	BIT(18)
> +#define NPCM_GDMA_SRCB(n)	(n * 0x20 + 0x04)
> +#define NPCM_GDMA_DSTB(n)	(n * 0x20 + 0x08)
> +#define NPCM_GDMA_TCNT(n)	(n * 0x20 + 0x0C)
> +#define NPCM_GDMA_CSRC(n)	(n * 0x20 + 0x10)
> +#define NPCM_GDMA_CDST(n)	(n * 0x20 + 0x14)
> +#define NPCM_GDMA_CTCNT(n)	(n * 0x20 + 0x18)
> +#define NPCM_GDMA_MUX(n)	(((n & 0xFFFF) >> 12) * 2 + 6)
> +#define GDMA_CH0_EN		GENMASK(6, 5)
> +#define GDMA_CH1_EN		GENMASK(22, 21)
> +
> +struct npcm_i3c_cmd {
> +	u8 addr;
> +	bool rnw;
> +	u8 *in;
> +	const void *out;
> +	unsigned int len;
> +	unsigned int read_len;
> +	bool continued;
> +	bool use_dma;
> +};
> +
> +struct npcm_i3c_xfer {
> +	struct list_head node;
> +	struct completion comp;
> +	int ret;
> +	unsigned int type;
> +	unsigned int ncmds;
> +	struct npcm_i3c_cmd cmds[];
> +};
> +
> +struct npcm_i3c_regs_save {
> +	u32 mconfig;
> +	u32 mdynaddr;
> +};
> +
> +struct npcm_dma_xfer_desc {
> +	const u8 *out;
> +	u8 *in;
> +	u32 len;
> +	bool rnw;
> +	bool end;
> +};
> +/**
> + * struct npcm_i3c_master - npcm845 I3C Master structure
> + * @base: I3C master controller
> + * @dev: Corresponding device
> + * @regs: Memory mapping
> + * @saved_regs: Volatile values for PM operations
> + * @free_slots: Bit array of available slots
> + * @addrs: Array containing the dynamic addresses of each attached device
> + * @descs: Array of descriptors, one per attached device
> + * @hj_work: Hot-join work
> + * @irq: Main interrupt
> + * @pclk: System clock
> + * @fclk: Fast clock (bus)
> + * @sclk: Slow clock (other events)
> + * @xferqueue: Transfer queue structure
> + * @xferqueue.list: List member
> + * @xferqueue.cur: Current ongoing transfer
> + * @xferqueue.lock: Queue lock
> + * @ibi: IBI structure
> + * @ibi.num_slots: Number of slots available in @ibi.slots
> + * @ibi.slots: Available IBI slots
> + * @ibi.tbq_slot: To be queued IBI slot
> + * @ibi.lock: IBI lock
> + * @lock: Transfer lock, prevent concurrent daa/priv_xfer/ccc
> + * @req_lock: protect between IBI isr and bus operation request
> + */
> +struct npcm_i3c_master {
> +	struct i3c_master_controller base;
> +	struct device *dev;
> +	void __iomem *regs;
> +	struct npcm_i3c_regs_save saved_regs;
> +	u32 free_slots;
> +	u8 addrs[NPCM_I3C_MAX_DEVS];
> +	struct i3c_dev_desc *descs[NPCM_I3C_MAX_DEVS];
> +	struct work_struct hj_work;
> +	int irq;
> +	struct clk *pclk;
> +	struct clk *fclk;
> +	struct {
> +		u32 i3c_pp_hi;
> +		u32 i3c_pp_lo;
> +		u32 i3c_pp_sda_rd_skew;
> +		u32 i3c_pp_sda_wr_skew;
> +		u32 i3c_od_hi;
> +		u32 i3c_od_lo;
> +	} scl_timing;
> +	struct {
> +		struct list_head list;
> +		struct npcm_i3c_xfer *cur;
> +	} xferqueue;
> +	struct {
> +		unsigned int num_slots;
> +		struct i3c_dev_desc **slots;
> +		struct i3c_ibi_slot *tbq_slot;
> +		/* Prevent races within IBI handlers */
> +		spinlock_t lock;
> +	} ibi;
> +	spinlock_t req_lock;
> +	struct mutex lock;
> +	struct dentry *debugfs;
> +
> +	/* For DMA */
> +	void __iomem *dma_regs;
> +	void __iomem *dma_ctl_regs;
> +	bool use_dma;
> +	struct completion xfer_comp;
> +	char *dma_tx_buf;
> +	char *dma_rx_buf;
> +	dma_addr_t dma_tx_addr;
> +	dma_addr_t dma_rx_addr;
> +	struct npcm_dma_xfer_desc dma_xfer;
> +
> +	bool en_hj;
> +};
> +
> +/**
> + * struct npcm_i3c_i2c_dev_data - Device specific data
> + * @index: Index in the master tables corresponding to this device
> + * @ibi: IBI slot index in the master structure
> + * @ibi_pool: IBI pool associated to this device
> + */
> +struct npcm_i3c_i2c_dev_data {
> +	u8 index;
> +	int ibi;
> +	struct i3c_generic_ibi_pool *ibi_pool;
> +};
> +
> +static DEFINE_MUTEX(npcm_i3c_dma_lock);

Why need globel lock for dma?

> +
> +static int npcm_i3c_master_wait_for_complete(struct npcm_i3c_master *master);
> +static void npcm_i3c_master_stop_dma(struct npcm_i3c_master *master);

Is it possible reorder function to avoid declear function here?

> +
> +static void npcm_i3c_master_dma_lock(void)
> +{
> +	mutex_lock(&npcm_i3c_dma_lock);
> +}
> +
> +static void npcm_i3c_master_dma_unlock(void)
> +{
> +	mutex_unlock(&npcm_i3c_dma_lock);
> +}

I think above two help functions is not nesseceary at all.

> +
> +static bool npcm_i3c_master_error(struct npcm_i3c_master *master)
> +{
> +	u32 mstatus, merrwarn;
> +
> +	mstatus = readl(master->regs + NPCM_I3C_MSTATUS);
> +	if (NPCM_I3C_MSTATUS_ERRWARN(mstatus)) {
> +		merrwarn = readl(master->regs + NPCM_I3C_MERRWARN);
> +		writel(merrwarn, master->regs + NPCM_I3C_MERRWARN);
> +
> +		/* Ignore timeout error */
> +		if (merrwarn & NPCM_I3C_MERRWARN_TIMEOUT) {
> +			dev_dbg(master->dev, "Warning condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
> +				mstatus, merrwarn);
> +			return false;
> +		}
> +
> +		dev_err(master->dev,
> +			"Error condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
> +			mstatus, merrwarn);
> +
> +		return true;
> +	}
> +
> +	return false;
> +}
> +
> +static void npcm_i3c_master_set_sda_skew(struct npcm_i3c_master *master, int skew)
> +{
> +	u32 val;
> +
> +	val = readl(master->regs + NPCM_I3C_MCONFIG) & ~NPCM_I3C_MCONFIG_SKEW_MASK;
> +	val |= NPCM_I3C_MCONFIG_SKEW(skew);
> +	writel(val, master->regs + NPCM_I3C_MCONFIG);
> +}
> +
> +static void npcm_i3c_master_enable_interrupts(struct npcm_i3c_master *master, u32 mask)
> +{
> +	writel(mask, master->regs + NPCM_I3C_MINTSET);
> +}
> +
> +static void npcm_i3c_master_disable_interrupts(struct npcm_i3c_master *master)
> +{
> +	u32 mask = readl(master->regs + NPCM_I3C_MINTSET);
> +
> +	writel(mask, master->regs + NPCM_I3C_MINTCLR);
> +}
> +
> +static void npcm_i3c_master_clear_merrwarn(struct npcm_i3c_master *master)
> +{
> +	/* Clear pending warnings */
> +	writel(readl(master->regs + NPCM_I3C_MERRWARN),
> +	       master->regs + NPCM_I3C_MERRWARN);
> +}
> +
> +static void npcm_i3c_master_flush_fifo(struct npcm_i3c_master *master)
> +{
> +	/* Flush FIFOs */
> +	writel(NPCM_I3C_MDATACTRL_FLUSHTB | NPCM_I3C_MDATACTRL_FLUSHRB,
> +	       master->regs + NPCM_I3C_MDATACTRL);
> +}
> +
> +static void npcm_i3c_master_flush_rx_fifo(struct npcm_i3c_master *master)
> +{
> +	writel(NPCM_I3C_MDATACTRL_FLUSHRB, master->regs + NPCM_I3C_MDATACTRL);
> +}
> +
> +static void npcm_i3c_master_reset_fifo_trigger(struct npcm_i3c_master *master)
> +{
> +	u32 reg;
> +
> +	/* Set RX and TX tigger levels, flush FIFOs */
> +	reg = NPCM_I3C_MDATACTRL_FLUSHTB |
> +	      NPCM_I3C_MDATACTRL_FLUSHRB |
> +	      NPCM_I3C_MDATACTRL_UNLOCK_TRIG |
> +	      NPCM_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL |
> +	      NPCM_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY;
> +	writel(reg, master->regs + NPCM_I3C_MDATACTRL);
> +}
> +
> +static void npcm_i3c_master_reset(struct npcm_i3c_master *master)
> +{
> +	npcm_i3c_master_clear_merrwarn(master);
> +	npcm_i3c_master_reset_fifo_trigger(master);
> +	npcm_i3c_master_disable_interrupts(master);
> +}
> +
> +static inline struct npcm_i3c_master *
> +to_npcm_i3c_master(struct i3c_master_controller *master)
> +{
> +	return container_of(master, struct npcm_i3c_master, base);
> +}
> +
> +static void npcm_i3c_master_hj_work(struct work_struct *work)
> +{
> +	struct npcm_i3c_master *master;
> +
> +	master = container_of(work, struct npcm_i3c_master, hj_work);
> +
> +	i3c_master_do_daa(&master->base);
> +}
> +
> +static struct i3c_dev_desc *
> +npcm_i3c_master_dev_from_addr(struct npcm_i3c_master *master,
> +			     unsigned int ibiaddr)
> +{
> +	int i;
> +
> +	for (i = 0; i < NPCM_I3C_MAX_DEVS; i++)
> +		if (master->addrs[i] == ibiaddr)
> +			break;
> +
> +	if (i == NPCM_I3C_MAX_DEVS)
> +		return NULL;
> +
> +	return master->descs[i];
> +}
> +
> +static void npcm_i3c_master_ack_ibi(struct npcm_i3c_master *master,
> +				   bool mandatory_byte)
> +{
> +	unsigned int ibi_ack_nack;
> +	u32 reg;
> +
> +	ibi_ack_nack = NPCM_I3C_MCTRL_REQUEST_IBI_ACKNACK;
> +	if (mandatory_byte)
> +		ibi_ack_nack |= NPCM_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE |
> +			NPCM_I3C_MCTRL_RDTERM(NPCM_I3C_MAX_IBI_PAYLOAD_SIZE);
> +	else
> +		ibi_ack_nack |= NPCM_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE;
> +
> +	writel(ibi_ack_nack, master->regs + NPCM_I3C_MCTRL);
> +	readl_poll_timeout(master->regs + NPCM_I3C_MSTATUS, reg,
> +			   NPCM_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
> +}
> +
> +static void npcm_i3c_master_nack_ibi(struct npcm_i3c_master *master)
> +{
> +	u32 reg;
> +
> +	writel(NPCM_I3C_MCTRL_REQUEST_IBI_ACKNACK |
> +	       NPCM_I3C_MCTRL_IBIRESP_NACK,
> +	       master->regs + NPCM_I3C_MCTRL);
> +	readl_poll_timeout(master->regs + NPCM_I3C_MSTATUS, reg,
> +			   NPCM_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
> +}
> +
> +static void npcm_i3c_master_emit_stop(struct npcm_i3c_master *master)
> +{
> +	u32 reg = readl(master->regs + NPCM_I3C_MSTATUS);
> +
> +	/* Do not emit stop in the IDLE or SLVREQ state */
> +	if (NPCM_I3C_MSTATUS_STATE_IDLE(reg) || NPCM_I3C_MSTATUS_STATE_SLVREQ(reg))
> +		return;
> +
> +	/*
> +	 * The spurious IBI event may change controller state to IBIACK, switch state
> +	 * to NORMACT before emitSTOP request.
> +	 */
> +	if (NPCM_I3C_MSTATUS_STATE_IBIACK(reg)) {
> +		npcm_i3c_master_nack_ibi(master);
> +		writel(NPCM_I3C_MINT_IBIWON, master->regs + NPCM_I3C_MSTATUS);
> +	}
> +
> +	writel(NPCM_I3C_MCTRL_REQUEST_STOP, master->regs + NPCM_I3C_MCTRL);
> +	readl_poll_timeout(master->regs + NPCM_I3C_MSTATUS, reg,
> +			   NPCM_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
> +
> +	/*
> +	 * This delay is necessary after the emission of a stop, otherwise eg.
> +	 * repeating IBIs do not get detected. There is a note in the manual
> +	 * about it, stating that the stop condition might not be settled
> +	 * correctly if a start condition follows too rapidly.
> +	 */
> +	udelay(1);
> +}
> +
> +static int npcm_i3c_master_handle_ibi(struct npcm_i3c_master *master,
> +				     struct i3c_dev_desc *dev)
> +{
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +	struct i3c_ibi_slot *slot;
> +	unsigned int count;
> +	u32 mdatactrl, val;
> +	int ret;
> +	u8 *buf;
> +
> +	if (!data) {
> +		dev_err_ratelimited(master->dev, "No data for addr 0x%x\n",
> +			dev->info.dyn_addr);
> +		goto no_ibi_pool;
> +	}
> +
> +	if (!data->ibi_pool) {
> +		dev_err_ratelimited(master->dev, "No ibi pool for addr 0x%x\n",
> +			master->addrs[data->index]);
> +		goto no_ibi_pool;
> +	}
> +	slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
> +	if (!slot) {
> +		dev_err_ratelimited(master->dev, "No free ibi slot\n");
> +		goto no_ibi_pool;
> +	}
> +
> +	slot->len = 0;
> +	buf = slot->data;
> +
> +	/*
> +	 * Sometimes I3C HW returns to IDLE state after IBIRCV completed,
> +	 * continue when state becomes IDLE.
> +	 */
> +	ret = readl_relaxed_poll_timeout(master->regs + NPCM_I3C_MSTATUS, val,
> +					 NPCM_I3C_MSTATUS_COMPLETE(val) |
> +					 NPCM_I3C_MSTATUS_STATE_IDLE(val),
> +					 0, 1000);
> +	if (ret) {
> +		dev_err(master->dev, "Timeout when polling for COMPLETE\n");
> +		if (NPCM_I3C_MSTATUS_RXPEND(val))
> +			npcm_i3c_master_flush_rx_fifo(master);
> +		i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);
> +		slot = NULL;
> +		goto handle_done;
> +	}
> +
> +	while (NPCM_I3C_MSTATUS_RXPEND(readl(master->regs + NPCM_I3C_MSTATUS))  &&
> +	       slot->len < NPCM_I3C_MAX_IBI_PAYLOAD_SIZE) {
> +		mdatactrl = readl(master->regs + NPCM_I3C_MDATACTRL);
> +		count = NPCM_I3C_MDATACTRL_RXCOUNT(mdatactrl);
> +		readsb(master->regs + NPCM_I3C_MRDATAB, buf, count);
> +		slot->len += count;
> +		buf += count;
> +	}
> +
> +handle_done:
> +	master->ibi.tbq_slot = slot;
> +
> +	return ret;
> +
> +no_ibi_pool:
> +	/* No ibi pool, drop the payload if received  */
> +	readl_relaxed_poll_timeout(master->regs + NPCM_I3C_MSTATUS, val,
> +				   NPCM_I3C_MSTATUS_COMPLETE(val) |
> +				   NPCM_I3C_MSTATUS_STATE_IDLE(val),
> +				   0, 1000);
> +	npcm_i3c_master_flush_rx_fifo(master);
> +	return -ENOSPC;
> +}
> +
> +static int npcm_i3c_master_handle_ibiwon(struct npcm_i3c_master *master, bool autoibi)
> +{
> +	struct npcm_i3c_i2c_dev_data *data;
> +	unsigned int ibitype, ibiaddr;
> +	struct i3c_dev_desc *dev;
> +	u32 status;
> +	int ret = 0;
> +
> +	status = readl(master->regs + NPCM_I3C_MSTATUS);
> +	ibitype = NPCM_I3C_MSTATUS_IBITYPE(status);
> +	ibiaddr = NPCM_I3C_MSTATUS_IBIADDR(status);
> +
> +	dev_dbg(master->dev, "ibitype=%d ibiaddr=%d\n", ibitype, ibiaddr);
> +	dev_dbg(master->dev, "ibiwon: mctrl=0x%x mstatus=0x%x\n",
> +		readl(master->regs + NPCM_I3C_MCTRL), status);
> +	/* Handle the critical responses to IBI's */
> +	switch (ibitype) {
> +	case NPCM_I3C_MSTATUS_IBITYPE_IBI:
> +		dev = npcm_i3c_master_dev_from_addr(master, ibiaddr);
> +		/* Bypass the invalid ibi with address 0 */
> +		if (!dev || ibiaddr == 0) {
> +			if (!autoibi) {
> +				npcm_i3c_master_nack_ibi(master);
> +				break;
> +			}
> +			/*
> +			 * Wait for complete to make sure the subsequent emitSTOP
> +			 * request will be performed in the correct state(NORMACT).
> +			 */
> +			readl_relaxed_poll_timeout(master->regs + NPCM_I3C_MSTATUS, status,
> +						   NPCM_I3C_MSTATUS_COMPLETE(status),
> +						   0, 1000);
> +			/* Flush the garbage data */
> +			if (NPCM_I3C_MSTATUS_RXPEND(status))
> +				npcm_i3c_master_flush_rx_fifo(master);
> +			break;
> +		}
> +		if (!autoibi) {
> +			if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD)
> +				npcm_i3c_master_ack_ibi(master, true);
> +			else
> +				npcm_i3c_master_ack_ibi(master, false);
> +		}
> +		npcm_i3c_master_handle_ibi(master, dev);
> +		break;
> +	case NPCM_I3C_MSTATUS_IBITYPE_HOT_JOIN:
> +		npcm_i3c_master_ack_ibi(master, false);
> +		break;
> +	case NPCM_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
> +		npcm_i3c_master_nack_ibi(master);
> +		status = readl(master->regs + NPCM_I3C_MSTATUS);
> +		/* Invalid event may be reported as MR request
> +		 * and sometimes produce dummy bytes. Flush the garbage data.
> +		 */
> +		if (NPCM_I3C_MSTATUS_RXPEND(status))
> +			npcm_i3c_master_flush_rx_fifo(master);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	/*
> +	 * If an error happened, we probably got interrupted and the exchange
> +	 * timedout. In this case we just drop everything, emit a stop and wait
> +	 * for the slave to interrupt again.
> +	 */
> +	if (npcm_i3c_master_error(master)) {
> +		if (master->ibi.tbq_slot) {
> +			data = i3c_dev_get_master_data(dev);
> +			i3c_generic_ibi_recycle_slot(data->ibi_pool,
> +						     master->ibi.tbq_slot);
> +			master->ibi.tbq_slot = NULL;
> +		}
> +
> +		dev_err(master->dev, "npcm_i3c_master_error in ibiwon\n");
> +		/*
> +		 * No need to emit stop here because the caller should do it
> +		 * if return error
> +		 */
> +		ret = -EIO;
> +		goto clear_ibiwon;
> +	}
> +
> +	/* Handle the non critical tasks */
> +	switch (ibitype) {
> +	case NPCM_I3C_MSTATUS_IBITYPE_IBI:
> +		npcm_i3c_master_emit_stop(master);
> +		if (dev && master->ibi.tbq_slot) {
> +			i3c_master_queue_ibi(dev, master->ibi.tbq_slot);
> +			master->ibi.tbq_slot = NULL;
> +		}
> +		break;
> +	case NPCM_I3C_MSTATUS_IBITYPE_HOT_JOIN:
> +		/* Emit stop to avoid the INVREQ error after DAA process */
> +		npcm_i3c_master_emit_stop(master);
> +		queue_work(master->base.wq, &master->hj_work);
> +		break;
> +	case NPCM_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
> +		ret = -EOPNOTSUPP;
> +	default:
> +		break;
> +	}
> +
> +clear_ibiwon:
> +	/* clear IBIWON status */
> +	writel(NPCM_I3C_MINT_IBIWON, master->regs + NPCM_I3C_MSTATUS);
> +	return ret;
> +}
> +
> +static void npcm_i3c_master_ibi_isr(struct npcm_i3c_master *master)
> +{
> +	u32 val, mstatus;
> +	int ret;
> +
> +	spin_lock(&master->req_lock);
> +
> +	/* Check slave ibi handled not yet */
> +	mstatus = readl(master->regs + NPCM_I3C_MSTATUS);
> +	if (!NPCM_I3C_MSTATUS_STATE_SLVREQ(mstatus))
> +		goto ibi_out;
> +
> +	/*
> +	 * IBIWON may be set before NPCM_I3C_MCTRL_REQUEST_AUTO_IBI, causing
> +	 * readl_relaxed_poll_timeout() to return immediately. Consequently,
> +	 * ibitype will be 0 since it was last updated only after the 8th SCL
> +	 * cycle, leading to missed client IBI handlers.
> +	 *
> +	 * Clear NPCM_I3C_MINT_IBIWON before sending NPCM_I3C_MCTRL_REQUEST_AUTO_IBI.
> +	 */
> +	writel(NPCM_I3C_MINT_IBIWON, master->regs + NPCM_I3C_MSTATUS);
> +
> +	/* Acknowledge the incoming interrupt with the AUTOIBI mechanism */
> +	writel(NPCM_I3C_MCTRL_REQUEST_AUTO_IBI |
> +	       NPCM_I3C_MCTRL_IBIRESP_AUTO |
> +	       NPCM_I3C_MCTRL_RDTERM(NPCM_I3C_MAX_IBI_PAYLOAD_SIZE),
> +	       master->regs + NPCM_I3C_MCTRL);
> +
> +	/* Wait for IBIWON, should take approximately 100us */
> +	ret = readl_relaxed_poll_timeout_atomic(master->regs + NPCM_I3C_MSTATUS, val,
> +					 NPCM_I3C_MSTATUS_IBIWON(val), 0, 1000);
> +	if (ret) {
> +		/* Cancel AUTOIBI if not started */
> +		val = readl(master->regs + NPCM_I3C_MCTRL);
> +		if (NPCM_I3C_MCTRL_REQUEST(val) == NPCM_I3C_MCTRL_REQUEST_AUTO_IBI)
> +			writel(0, master->regs + NPCM_I3C_MCTRL);
> +		dev_err(master->dev, "Timeout when polling for IBIWON\n");
> +		npcm_i3c_master_clear_merrwarn(master);
> +		npcm_i3c_master_emit_stop(master);
> +		goto ibi_out;
> +	}
> +
> +	if (npcm_i3c_master_handle_ibiwon(master, true))
> +		npcm_i3c_master_emit_stop(master);
> +ibi_out:
> +	spin_unlock(&master->req_lock);
> +}
> +
> +static irqreturn_t npcm_i3c_master_irq_handler(int irq, void *dev_id)
> +{
> +	struct npcm_i3c_master *master = (struct npcm_i3c_master *)dev_id;
> +	u32 active = readl(master->regs + NPCM_I3C_MINTMASKED), mstatus;
> +
> +	if (NPCM_I3C_MSTATUS_COMPLETE(active)) {
> +		/* Clear COMPLETE status before emit STOP */
> +		writel(NPCM_I3C_MINT_COMPLETE, master->regs + NPCM_I3C_MSTATUS);
> +		/* Disable COMPLETE interrupt */
> +		writel(NPCM_I3C_MINT_COMPLETE, master->regs + NPCM_I3C_MINTCLR);
> +
> +		if (master->dma_xfer.end) {
> +			/* Stop DMA to prevent receiving the data of other transaction */
> +			npcm_i3c_master_stop_dma(master);
> +			npcm_i3c_master_set_sda_skew(master, 0);
> +			npcm_i3c_master_emit_stop(master);
> +		}
> +
> +		complete(&master->xfer_comp);
> +
> +		return IRQ_HANDLED;
> +	}
> +
> +	if (NPCM_I3C_MSTATUS_SLVSTART(active)) {
> +		/* Clear the interrupt status */
> +		writel(NPCM_I3C_MINT_SLVSTART, master->regs + NPCM_I3C_MSTATUS);
> +
> +		/* Read I3C state */
> +		mstatus = readl(master->regs + NPCM_I3C_MSTATUS);
> +
> +		if (NPCM_I3C_MSTATUS_STATE_SLVREQ(mstatus)) {
> +			npcm_i3c_master_ibi_isr(master);
> +		} else {
> +			/*
> +			 * Workaround:
> +			 * SlaveStart event under bad signals condition. SLVSTART bit in
> +			 * MSTATUS may set even slave device doesn't holding I3C_SDA low,
> +			 * but actual SlaveStart event may happened concurently in this
> +			 * bad signals condition handler. Give a chance to check current
> +			 * work state and intmask to avoid actual SlaveStart cannot be
> +			 * trigger after we clear SlaveStart interrupt status.
> +			 */
> +
> +			/* Check if state change after we clear interrupt status */
> +			active = readl(master->regs + NPCM_I3C_MINTMASKED);
> +			mstatus = readl(master->regs + NPCM_I3C_MSTATUS);
> +
> +			if (NPCM_I3C_MSTATUS_STATE_SLVREQ(mstatus)) {
> +				if (!NPCM_I3C_MSTATUS_SLVSTART(active))
> +					npcm_i3c_master_ibi_isr(master);
> +				/* else: handle interrupt in next time */
> +			}
> +		}
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int npcm_i3c_master_bus_init(struct i3c_master_controller *m)
> +{
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct i3c_bus *bus = i3c_master_get_bus(m);
> +	struct i3c_device_info info = {};
> +	unsigned long fclk_rate, fclk_period_ns;
> +	unsigned long i3c_scl_rate, i2c_scl_rate;
> +	unsigned int pp_high_period_ns, od_low_period_ns, i2c_period_ns;
> +	unsigned int scl_period_ns;
> +	u32 ppbaud, pplow, odhpp, odbaud, i2cbaud, reg;
> +	int ret;
> +
> +	/* Timings derivation */
> +	fclk_rate = clk_get_rate(master->fclk);
> +	if (!fclk_rate)
> +		return -EINVAL;
> +
> +	fclk_period_ns = DIV_ROUND_UP(1000000000, fclk_rate);
> +
> +	/*
> +	 * Configure for Push-Pull mode.
> +	 */
> +	if (master->scl_timing.i3c_pp_hi >= I3C_SCL_PP_PERIOD_NS_MIN &&
> +	    master->scl_timing.i3c_pp_lo >= master->scl_timing.i3c_pp_hi) {
> +		ppbaud = DIV_ROUND_UP(master->scl_timing.i3c_pp_hi, fclk_period_ns) - 1;
> +		if (ppbaud > NPCM_I3C_MAX_PPBAUD)
> +			ppbaud = NPCM_I3C_MAX_PPBAUD;
> +		pplow = DIV_ROUND_UP(master->scl_timing.i3c_pp_lo, fclk_period_ns)
> +			- (ppbaud + 1);
> +		if (pplow > NPCM_I3C_MAX_PPLOW)
> +			pplow = NPCM_I3C_MAX_PPLOW;
> +		bus->scl_rate.i3c = 1000000000 / (((ppbaud + 1) * 2 + pplow) * fclk_period_ns);
> +	} else {
> +		scl_period_ns = DIV_ROUND_UP(1000000000, bus->scl_rate.i3c);
> +		if (bus->scl_rate.i3c == 10000000) {
> +			/* Workaround for npcm8xx: 40/60 ns */
> +			ppbaud = DIV_ROUND_UP(40, fclk_period_ns) - 1;
> +			pplow = DIV_ROUND_UP(20, fclk_period_ns);
> +		} else {
> +			/* 50% duty-cycle */
> +			ppbaud = DIV_ROUND_UP((scl_period_ns / 2), fclk_period_ns) - 1;
> +			pplow = 0;
> +		}
> +		if (ppbaud > NPCM_I3C_MAX_PPBAUD)
> +			ppbaud = NPCM_I3C_MAX_PPBAUD;
> +	}
> +	pp_high_period_ns = (ppbaud + 1) * fclk_period_ns;
> +
> +	/*
> +	 * Configure for Open-Drain mode.
> +	 */
> +	if (master->scl_timing.i3c_od_hi >= pp_high_period_ns &&
> +	    master->scl_timing.i3c_od_lo >= I3C_SCL_OD_LOW_PERIOD_NS_MIN) {
> +		if (master->scl_timing.i3c_od_hi == pp_high_period_ns)
> +			odhpp = 1;
> +		else
> +			odhpp = 0;
> +		odbaud = DIV_ROUND_UP(master->scl_timing.i3c_od_lo, pp_high_period_ns) - 1;
> +	} else {
> +		/* Set default OD timing: 1MHz/1000ns with 50% duty cycle */
> +		odhpp = 0;
> +		odbaud = DIV_ROUND_UP(500, pp_high_period_ns) - 1;
> +	}
> +	if (odbaud > NPCM_I3C_MAX_ODBAUD)
> +		odbaud = NPCM_I3C_MAX_ODBAUD;
> +	od_low_period_ns = (odbaud + 1) * pp_high_period_ns;
> +
> +	/* Configure for I2C mode */
> +	i2c_period_ns = DIV_ROUND_UP(1000000000, bus->scl_rate.i2c);
> +	if (i2c_period_ns < od_low_period_ns * 2)
> +		i2c_period_ns = od_low_period_ns * 2;
> +	i2cbaud = DIV_ROUND_UP(i2c_period_ns, od_low_period_ns) - 2;
> +	if (i2cbaud > NPCM_I3C_MAX_I2CBAUD)
> +		i2cbaud = NPCM_I3C_MAX_I2CBAUD;
> +
> +	i3c_scl_rate = 1000000000 / (((ppbaud + 1) * 2 + pplow) * fclk_period_ns);
> +	i2c_scl_rate = 1000000000 / ((i2cbaud + 2) * od_low_period_ns);
> +
> +	reg = NPCM_I3C_MCONFIG_MASTER_EN |
> +	      NPCM_I3C_MCONFIG_DISTO(0) |
> +	      NPCM_I3C_MCONFIG_HKEEP(3) |
> +	      NPCM_I3C_MCONFIG_ODSTOP(1) |
> +	      NPCM_I3C_MCONFIG_PPBAUD(ppbaud) |
> +	      NPCM_I3C_MCONFIG_PPLOW(pplow) |
> +	      NPCM_I3C_MCONFIG_ODBAUD(odbaud) |
> +	      NPCM_I3C_MCONFIG_ODHPP(odhpp) |
> +	      NPCM_I3C_MCONFIG_SKEW(0) |
> +	      NPCM_I3C_MCONFIG_I2CBAUD(i2cbaud);
> +	writel(reg, master->regs + NPCM_I3C_MCONFIG);
> +
> +	dev_dbg(master->dev, "dts: i3c rate=%lu, i2c rate=%lu\n",
> +		bus->scl_rate.i3c, bus->scl_rate.i2c);
> +	dev_info(master->dev, "fclk=%lu, period_ns=%lu\n", fclk_rate, fclk_period_ns);
> +	dev_info(master->dev, "i3c scl_rate=%lu\n", i3c_scl_rate);
> +	dev_info(master->dev, "i2c scl_rate=%lu\n", i2c_scl_rate);
> +	dev_info(master->dev, "pp_high=%u, pp_low=%lu\n", pp_high_period_ns,
> +			(ppbaud + 1 + pplow) * fclk_period_ns);
> +	dev_info(master->dev, "pp_sda_rd_skew=%d, pp_sda_wr_skew=%d\n",
> +			master->scl_timing.i3c_pp_sda_rd_skew,
> +			master->scl_timing.i3c_pp_sda_wr_skew);
> +	dev_info(master->dev, "od_high=%d, od_low=%d\n",
> +			odhpp ? pp_high_period_ns : od_low_period_ns, od_low_period_ns);
> +	dev_dbg(master->dev, "i2c_high=%u, i2c_low=%u\n", ((i2cbaud >> 1) + 1) * od_low_period_ns,
> +			((i2cbaud >> 1) + 1 + (i2cbaud % 2)) * od_low_period_ns);
> +	dev_dbg(master->dev, "ppbaud=%d, pplow=%d, odbaud=%d, i2cbaud=%d\n",
> +		ppbaud, pplow, odbaud, i2cbaud);
> +	dev_info(master->dev, "mconfig=0x%x\n", readl(master->regs + NPCM_I3C_MCONFIG));
> +	/* Master core's registration */
> +	ret = i3c_master_get_free_addr(m, 0);
> +	if (ret < 0)
> +		return ret;
> +
> +	info.dyn_addr = ret;
> +	reg = readl(master->regs + NPCM_I3C_VENDORID);
> +	info.pid = (NPCM_I3C_VENDORID_VID(reg) << 33) | readl(master->regs + NPCM_I3C_PARTNO);
> +
> +	writel(NPCM_MDYNADDR_VALID | NPCM_MDYNADDR_ADDR(info.dyn_addr),
> +	       master->regs + NPCM_I3C_MDYNADDR);
> +
> +	ret = i3c_master_set_info(&master->base, &info);
> +
> +	return ret;
> +}
> +
> +static void npcm_i3c_master_bus_cleanup(struct i3c_master_controller *m)
> +{
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +
> +	npcm_i3c_master_disable_interrupts(master);
> +
> +	/* Disable master */
> +	writel(0, master->regs + NPCM_I3C_MCONFIG);
> +}
> +
> +static int npcm_i3c_master_reserve_slot(struct npcm_i3c_master *master)
> +{
> +	unsigned int slot;
> +
> +	if (!(master->free_slots & GENMASK(NPCM_I3C_MAX_DEVS - 1, 0)))
> +		return -ENOSPC;
> +
> +	slot = ffs(master->free_slots) - 1;
> +
> +	master->free_slots &= ~BIT(slot);
> +
> +	return slot;
> +}
> +
> +static void npcm_i3c_master_release_slot(struct npcm_i3c_master *master,
> +					unsigned int slot)
> +{
> +	master->free_slots |= BIT(slot);
> +}
> +
> +static int npcm_i3c_master_attach_i3c_dev(struct i3c_dev_desc *dev)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data;
> +	int slot;
> +
> +	slot = npcm_i3c_master_reserve_slot(master);
> +	if (slot < 0)
> +		return slot;
> +
> +	data = kzalloc(sizeof(*data), GFP_KERNEL);
> +	if (!data) {
> +		npcm_i3c_master_release_slot(master, slot);
> +		return -ENOMEM;
> +	}
> +
> +	data->ibi = -1;
> +	data->index = slot;
> +	master->addrs[slot] = dev->info.dyn_addr ? dev->info.dyn_addr :
> +						   dev->info.static_addr;
> +	master->descs[slot] = dev;
> +
> +	i3c_dev_set_master_data(dev, data);
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
> +					   u8 old_dyn_addr)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +
> +	master->addrs[data->index] = dev->info.dyn_addr ? dev->info.dyn_addr :
> +							  dev->info.static_addr;
> +
> +	return 0;
> +}
> +
> +static void npcm_i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
> +{
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +
> +	master->addrs[data->index] = 0;
> +	npcm_i3c_master_release_slot(master, data->index);
> +
> +	kfree(data);
> +}
> +
> +static int npcm_i3c_master_attach_i2c_dev(struct i2c_dev_desc *dev)
> +{
> +	struct i3c_master_controller *m = i2c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data;
> +	int slot;
> +
> +	slot = npcm_i3c_master_reserve_slot(master);
> +	if (slot < 0)
> +		return slot;
> +
> +	data = kzalloc(sizeof(*data), GFP_KERNEL);
> +	if (!data) {
> +		npcm_i3c_master_release_slot(master, slot);
> +		return -ENOMEM;
> +	}
> +
> +	data->index = slot;
> +	master->addrs[slot] = dev->addr;
> +
> +	i2c_dev_set_master_data(dev, data);
> +
> +	return 0;
> +}
> +
> +static void npcm_i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
> +{
> +	struct npcm_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
> +	struct i3c_master_controller *m = i2c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +
> +	npcm_i3c_master_release_slot(master, data->index);
> +
> +	kfree(data);
> +}
> +
> +static int npcm_i3c_master_readb(struct npcm_i3c_master *master, u8 *dst,
> +				unsigned int len)
> +{
> +	int ret, i;
> +	u32 reg;
> +
> +	for (i = 0; i < len; i++) {
> +		ret = readl_poll_timeout_atomic(master->regs + NPCM_I3C_MSTATUS,
> +						reg,
> +						NPCM_I3C_MSTATUS_RXPEND(reg),
> +						0, 1000);
> +		if (ret)
> +			return ret;
> +
> +		dst[i] = readl(master->regs + NPCM_I3C_MRDATAB);
> +	}
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_master_do_daa_locked(struct npcm_i3c_master *master,
> +					u8 *addrs, unsigned int *count)
> +{
> +	u64 prov_id[NPCM_I3C_MAX_DEVS] = {}, nacking_prov_id = 0;
> +	unsigned int dev_nb = 0, last_addr = 0;
> +	unsigned long start = jiffies;
> +	u32 reg;
> +	int ret, i;
> +	int dyn_addr;
> +
> +	npcm_i3c_master_flush_fifo(master);
> +
> +	while (true) {
> +		/* Enter/proceed with DAA */
> +		writel(NPCM_I3C_MCTRL_REQUEST_PROC_DAA |
> +		       NPCM_I3C_MCTRL_TYPE_I3C |
> +		       NPCM_I3C_MCTRL_IBIRESP_MANUAL |
> +		       NPCM_I3C_MCTRL_DIR(NPCM_I3C_MCTRL_DIR_WRITE),
> +		       master->regs + NPCM_I3C_MCTRL);
> +
> +		/*
> +		 * Either one slave will send its ID, or the assignment process
> +		 * is done.
> +		 */
> +		ret = readl_relaxed_poll_timeout_atomic(master->regs + NPCM_I3C_MSTATUS,
> +						reg,
> +						NPCM_I3C_MSTATUS_RXPEND(reg) |
> +						NPCM_I3C_MSTATUS_MCTRLDONE(reg),
> +						0, 1000);
> +		if (ret)
> +			return ret;
> +
> +		if (time_after(jiffies, start + msecs_to_jiffies(3000))) {
> +			npcm_i3c_master_emit_stop(master);
> +			dev_info(master->dev, "do_daa expired\n");
> +			break;
> +		}
> +		/* runtime do_daa may ibiwon by others slave devices */
> +		if (NPCM_I3C_MSTATUS_IBIWON(reg)) {
> +			ret = npcm_i3c_master_handle_ibiwon(master, false);
> +			if (ret) {
> +				dev_err(master->dev, "daa: handle ibi event fail, ret=%d\n", ret);
> +				return ret;
> +			}
> +			continue;
> +		}
> +
> +		if (dev_nb == NPCM_I3C_MAX_DEVS) {
> +			npcm_i3c_master_emit_stop(master);
> +			dev_info(master->dev, "Reach max devs\n");
> +			break;
> +		}
> +		if (NPCM_I3C_MSTATUS_RXPEND(reg)) {
> +			u8 data[6];
> +
> +			/* Give the slave device a suitable dynamic address */
> +			dyn_addr = i3c_master_get_free_addr(&master->base, last_addr + 1);
> +			if (dyn_addr < 0)
> +				return dyn_addr;
> +			writel(dyn_addr, master->regs + NPCM_I3C_MWDATAB);
> +
> +			/*
> +			 * We only care about the 48-bit provisional ID yet to
> +			 * be sure a device does not nack an address twice.
> +			 * Otherwise, we would just need to flush the RX FIFO.
> +			 */
> +			ret = npcm_i3c_master_readb(master, data, 6);
> +			if (ret)
> +				return ret;
> +
> +			for (i = 0; i < 6; i++)
> +				prov_id[dev_nb] |= (u64)(data[i]) << (8 * (5 - i));
> +
> +			/* We do not care about the BCR and DCR yet */
> +			ret = npcm_i3c_master_readb(master, data, 2);
> +			if (ret)
> +				return ret;
> +		} else if (NPCM_I3C_MSTATUS_MCTRLDONE(reg)) {
> +			if ((NPCM_I3C_MSTATUS_STATE_IDLE(reg) |
> +			     NPCM_I3C_MSTATUS_STATE_SLVREQ(reg)) &&
> +			    NPCM_I3C_MSTATUS_COMPLETE(reg)) {
> +				/*
> +				 * Sometimes the controller state is SLVREQ after
> +				 * DAA request completed, treat it as normal end.
> +				 *
> +				 * All devices received and acked they dynamic
> +				 * address, this is the natural end of the DAA
> +				 * procedure.
> +				 */
> +				break;
> +			} else if (NPCM_I3C_MSTATUS_NACKED(reg)) {
> +				/* No I3C devices attached */
> +				if (dev_nb == 0) {
> +					npcm_i3c_master_emit_stop(master);
> +					break;
> +				}
> +
> +				/*
> +				 * A slave device nacked the address, this is
> +				 * allowed only once, DAA will be stopped and
> +				 * then resumed. The same device is supposed to
> +				 * answer again immediately and shall ack the
> +				 * address this time.
> +				 */
> +				if (prov_id[dev_nb] == nacking_prov_id)
> +					return -EIO;
> +
> +				dev_nb--;
> +				nacking_prov_id = prov_id[dev_nb];
> +				npcm_i3c_master_emit_stop(master);
> +
> +				continue;
> +			} else {
> +				return -EIO;
> +			}
> +		}
> +
> +		/* Wait for the slave to be ready to receive its address */
> +		ret = readl_poll_timeout_atomic(master->regs + NPCM_I3C_MSTATUS,
> +						reg,
> +						NPCM_I3C_MSTATUS_MCTRLDONE(reg) &&
> +						NPCM_I3C_MSTATUS_STATE_DAA(reg) &&
> +						NPCM_I3C_MSTATUS_BETWEEN(reg),
> +						0, 1000);
> +		if (ret)
> +			return ret;
> +
> +		addrs[dev_nb] = dyn_addr;
> +		dev_dbg(master->dev, "DAA: device %d assigned to 0x%02x\n",
> +			dev_nb, addrs[dev_nb]);
> +		last_addr = addrs[dev_nb++];
> +	}
> +
> +	*count = dev_nb;
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_update_ibirules(struct npcm_i3c_master *master)
> +{
> +	struct i3c_dev_desc *dev;
> +	u32 reg_mbyte = 0, reg_nobyte = NPCM_I3C_IBIRULES_NOBYTE;
> +	unsigned int mbyte_addr_ok = 0, mbyte_addr_ko = 0, nobyte_addr_ok = 0,
> +		nobyte_addr_ko = 0;
> +	bool list_mbyte = false, list_nobyte = false;
> +
> +	/* Create the IBIRULES register for both cases */
> +	i3c_bus_for_each_i3cdev(&master->base.bus, dev) {
> +		if (I3C_BCR_DEVICE_ROLE(dev->info.bcr) == I3C_BCR_I3C_MASTER) {
> +			if (!(dev->info.bcr & I3C_BCR_IBI_REQ_CAP))
> +				continue;
> +		}
> +
> +		if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD) {
> +			reg_mbyte |= NPCM_I3C_IBIRULES_ADDR(mbyte_addr_ok,
> +							   dev->info.dyn_addr);
> +
> +			/* IBI rules cannot be applied to devices with MSb=1 */
> +			if (dev->info.dyn_addr & BIT(7))
> +				mbyte_addr_ko++;
> +			else
> +				mbyte_addr_ok++;
> +		} else {
> +			reg_nobyte |= NPCM_I3C_IBIRULES_ADDR(nobyte_addr_ok,
> +							    dev->info.dyn_addr);
> +
> +			/* IBI rules cannot be applied to devices with MSb=1 */
> +			if (dev->info.dyn_addr & BIT(7))
> +				nobyte_addr_ko++;
> +			else
> +				nobyte_addr_ok++;
> +		}
> +	}
> +
> +	/* Device list cannot be handled by hardware */
> +	if (!mbyte_addr_ko && mbyte_addr_ok <= NPCM_I3C_IBIRULES_ADDRS)
> +		list_mbyte = true;
> +
> +	if (!nobyte_addr_ko && nobyte_addr_ok <= NPCM_I3C_IBIRULES_ADDRS)
> +		list_nobyte = true;
> +
> +	/* No list can be properly handled, return an error */
> +	if (!list_mbyte && !list_nobyte)
> +		return -ERANGE;
> +
> +	/* Pick the first list that can be handled by hardware, randomly */
> +	if (list_mbyte)
> +		writel(reg_mbyte, master->regs + NPCM_I3C_IBIRULES);
> +	else
> +		writel(reg_nobyte, master->regs + NPCM_I3C_IBIRULES);
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_master_do_daa(struct i3c_master_controller *m)
> +{
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	u8 addrs[NPCM_I3C_MAX_DEVS];
> +	unsigned int dev_nb;
> +	unsigned long flags;
> +	int ret, i;
> +
> +	mutex_lock(&master->lock);
> +	spin_lock_irqsave(&master->req_lock, flags);
> +	/*
> +	 * Fix SCL/SDA timing issue during DAA.
> +	 * Set SKEW bit to 1 before initiating a DAA, set SKEW bit to 0
> +	 * after DAA is completed.
> +	 */
> +	npcm_i3c_master_set_sda_skew(master, 1);
> +	ret = npcm_i3c_master_do_daa_locked(master, addrs, &dev_nb);
> +	npcm_i3c_master_set_sda_skew(master, 0);
> +	spin_unlock_irqrestore(&master->req_lock, flags);
> +	mutex_unlock(&master->lock);
> +	if (ret) {
> +		npcm_i3c_master_emit_stop(master);
> +		npcm_i3c_master_clear_merrwarn(master);
> +		goto daa_out;
> +	}
> +
> +	/* Register all devices who participated to the core */
> +	for (i = 0; i < dev_nb; i++) {
> +		ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
> +		if (ret)
> +			dev_err(master->dev, "Unable to add i3c dev at 0x%x, err %d\n",
> +				addrs[i], ret);
> +	}
> +
> +	/* Configure IBI auto-rules */
> +	ret = npcm_i3c_update_ibirules(master);
> +	if (ret)
> +		dev_err(master->dev, "Cannot handle such a list of devices");
> +
> +daa_out:
> +	/* No Slave ACK */
> +	if (ret == -EIO)
> +		return 0;
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_read(struct npcm_i3c_master *master,
> +			       u8 *in, unsigned int len)
> +{
> +	int offset = 0, i;
> +	u32 mdctrl, mstatus;
> +	bool completed = false;
> +	unsigned int count;
> +	unsigned long start = jiffies;
> +
> +	while (!completed) {
> +		mstatus = readl(master->regs + NPCM_I3C_MSTATUS);
> +		if (NPCM_I3C_MSTATUS_COMPLETE(mstatus) != 0)
> +			completed = true;
> +
> +		if (time_after(jiffies, start + msecs_to_jiffies(1000))) {
> +			dev_dbg(master->dev, "I3C read timeout\n");
> +			return -ETIMEDOUT;
> +		}
> +
> +		mdctrl = readl(master->regs + NPCM_I3C_MDATACTRL);
> +		count = NPCM_I3C_MDATACTRL_RXCOUNT(mdctrl);
> +		if (offset + count > len) {
> +			dev_err(master->dev, "I3C receive length too long!\n");
> +			return -EINVAL;
> +		}
> +		for (i = 0; i < count; i++)
> +			in[offset + i] = readl(master->regs + NPCM_I3C_MRDATAB);
> +
> +		offset += count;
> +	}
> +
> +	return offset;
> +}
> +
> +static int npcm_i3c_master_write(struct npcm_i3c_master *master,
> +				const u8 *out, unsigned int len)
> +{
> +	int offset = 0, ret;
> +	u32 mdctrl;
> +
> +	while (offset < len) {
> +		ret = readl_poll_timeout(master->regs + NPCM_I3C_MDATACTRL,
> +					 mdctrl,
> +					 !(mdctrl & NPCM_I3C_MDATACTRL_TXFULL),
> +					 0, 1000);
> +		if (ret)
> +			return ret;
> +
> +		/*
> +		 * The last byte to be sent over the bus must either have the
> +		 * "end" bit set or be written in MWDATABE.
> +		 */
> +		if (likely(offset < (len - 1)))
> +			writel(out[offset++], master->regs + NPCM_I3C_MWDATAB);
> +		else
> +			writel(out[offset++], master->regs + NPCM_I3C_MWDATABE);
> +	}
> +
> +	return 0;
> +}
> +
> +static void npcm_i3c_master_stop_dma(struct npcm_i3c_master *master)
> +{
> +	writel(0, master->dma_regs + NPCM_GDMA_CTL(DMA_CH_TX));
> +	writel(0, master->dma_regs + NPCM_GDMA_CTL(DMA_CH_RX));
> +	writel(0, master->regs + NPCM_I3C_MDMACTRL);
> +
> +	/* Disable COMPLETE interrupt */
> +	writel(NPCM_I3C_MINT_COMPLETE, master->regs + NPCM_I3C_MINTCLR);
> +}
> +
> +static void npcm_i3c_master_write_dma_table(const u8 *src, u32 *dst, int len)
> +{
> +	int i;
> +
> +	if (len > MAX_DMA_COUNT)
> +		return;
> +
> +	for (i = 0; i < len; i++)
> +		dst[i] = (u32)src[i] & 0xFF;
> +
> +	/* Set end bit for last byte */
> +	dst[len - 1] |= 0x100;
> +}
> +
> +static int npcm_i3c_master_start_dma(struct npcm_i3c_master *master)
> +{
> +	struct npcm_dma_xfer_desc *xfer = &master->dma_xfer;
> +	int ch = xfer->rnw ? DMA_CH_RX : DMA_CH_TX;
> +	u32 val;
> +
> +	if (!xfer->len)
> +		return 0;
> +
> +	dev_dbg(master->dev, "start dma for %s, count %d\n",
> +		xfer->rnw ? "R" : "W", xfer->len);
> +
> +	/* Set DMA transfer count */
> +	writel(xfer->len, master->dma_regs + NPCM_GDMA_TCNT(ch));
> +
> +	/* Write data to DMA TX table */
> +	if (!xfer->rnw)
> +		npcm_i3c_master_write_dma_table(xfer->out,
> +					       (u32 *)master->dma_tx_buf,
> +					       xfer->len);
> +
> +	/*
> +	 * Setup I3C DMA control
> +	 * 1 byte DMA width
> +	 * Enable DMA util disabled
> +	 */
> +	val = NPCM_I3C_MDMACTRL_DMAWIDTH(1);
> +	val |= xfer->rnw ? NPCM_I3C_MDMACTRL_DMAFB(2) : NPCM_I3C_MDMACTRL_DMATB(2);
> +	writel(val, master->regs + NPCM_I3C_MDMACTRL);
> +
> +	/*
> +	 * Enable DMA
> +	 * Source Address Fixed for RX
> +	 * Destination Address Fixed for TX
> +	 * Use 32-bit transfer width for TX (queal to MWDATAB register width)
> +	 */
> +	val = NPCM_GDMA_CTL_GDMAEN;
> +	if (xfer->rnw)
> +		val |= NPCM_GDMA_CTL_SAFIX | NPCM_GDMA_CTL_GDMAMS(2);
> +	else
> +		val |= NPCM_GDMA_CTL_DAFIX | NPCM_GDMA_CTL_GDMAMS(1) | NPCM_GDMA_CTL_TWS(2);
> +	writel(val, master->dma_regs + NPCM_GDMA_CTL(ch));
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_master_wait_for_complete(struct npcm_i3c_master *master)
> +{
> +	struct npcm_dma_xfer_desc *xfer = &master->dma_xfer;
> +	int ch = xfer->rnw ? DMA_CH_RX : DMA_CH_TX;
> +	u32 count;
> +	int ret;
> +
> +	ret = wait_for_completion_timeout(&master->xfer_comp, msecs_to_jiffies(100));
> +	if (!ret) {
> +		dev_err(master->dev, "DMA transfer timeout (%s)\n", xfer->rnw ? "Read" : "write");
> +		dev_err(master->dev, "mstatus = 0x%02x\n", readl(master->regs + NPCM_I3C_MSTATUS));
> +		return -ETIMEDOUT;
> +	}
> +
> +	/* Get the DMA transfer count */
> +	count = readl(master->dma_regs + NPCM_GDMA_CTCNT(ch));
> +	count = (count > xfer->len) ? 0 : (xfer->len - count);
> +	dev_dbg(master->dev, "dma xfer count %u\n", count);
> +	if (xfer->rnw)
> +		memcpy(xfer->in, master->dma_rx_buf, count);
> +	if (count != xfer->len)
> +		dev_dbg(master->dev, "short dma xfer(%s), want %d transfer %d\n",
> +			xfer->rnw ? "R" : "W", xfer->len, count);
> +
> +	npcm_i3c_master_stop_dma(master);
> +
> +	return count;
> +}
> +
> +static int npcm_i3c_send_broadcast(struct npcm_i3c_master *master)
> +{
> +	u32 reg;
> +	int ret;
> +
> +	writel(NPCM_I3C_MCTRL_REQUEST_START_ADDR |
> +	       NPCM_I3C_MCTRL_TYPE_I3C |
> +	       NPCM_I3C_MCTRL_IBIRESP_AUTO |
> +	       NPCM_I3C_MCTRL_DIR(0) |
> +	       NPCM_I3C_MCTRL_ADDR(I3C_BROADCAST_ADDR) |
> +	       NPCM_I3C_MCTRL_RDTERM(NPCM_I3C_MAX_IBI_PAYLOAD_SIZE),
> +	       master->regs + NPCM_I3C_MCTRL);
> +	ret = readl_poll_timeout(master->regs + NPCM_I3C_MSTATUS, reg,
> +				 NPCM_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
> +	if (ret)
> +		return -EIO;
> +
> +	if (NPCM_I3C_MSTATUS_IBIWON(reg)) {
> +		ret = npcm_i3c_master_handle_ibiwon(master, true);
> +		if (ret) {
> +			dev_err(master->dev, "xfer read: handle ibi event fail, ret=%d\n", ret);
> +			return -EIO;
> +		}
> +
> +		/* Clear COMPLETE status of this IBI transaction */
> +		writel(NPCM_I3C_MINT_COMPLETE, master->regs + NPCM_I3C_MSTATUS);
> +		return 1;
> +	}
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_master_xfer(struct npcm_i3c_master *master,
> +			       bool rnw, unsigned int xfer_type, u8 addr,
> +			       u8 *in, const u8 *out, unsigned int xfer_len,
> +			       unsigned int *read_len, bool continued,
> +			       bool use_dma, bool first)
> +{
> +	u32 reg, rdterm = *read_len, mstatus, ibiresp;
> +	int ret, i, count, space;
> +	unsigned long flags;
> +	unsigned long start;
> +	bool bus_locked = false;
> +
> +	if (rdterm > NPCM_I3C_MAX_RDTERM)
> +		rdterm = NPCM_I3C_MAX_RDTERM;
> +
> +	/* Prevent fifo operation from delay by interrupt */
> +	if (!use_dma)
> +		local_irq_disable();
> +	else
> +		npcm_i3c_master_dma_lock();
> +
> +	/* Prevent DMA start while IBI isr is running */
> +	spin_lock_irqsave(&master->req_lock, flags);
> +	bus_locked = true;
> +
> +	/*
> +	 * There is a chance that first tx data bit is lost when it
> +	 * is not ready in FIFO right after address phase.
> +	 * Prepare data before starting the transfer to fix this problem.
> +	 */
> +	if (!rnw && xfer_len && !use_dma) {
> +		ret = readl_poll_timeout(master->regs + NPCM_I3C_MDATACTRL,
> +					 reg,
> +					 !(reg & NPCM_I3C_MDATACTRL_TXFULL),
> +					 0, 1000);
> +		if (ret) {
> +			bus_locked = false;
> +			spin_unlock_irqrestore(&master->req_lock, flags);
> +			local_irq_enable();
> +			return ret;
> +		}
> +
> +		reg = readl(master->regs + NPCM_I3C_MDATACTRL);
> +		space = NPCM_I3C_FIFO_SIZE - NPCM_I3C_MDATACTRL_TXCOUNT(reg);
> +		count = xfer_len > space ? space : xfer_len;
> +		for (i = 0; i < count; i++) {
> +			if (i == xfer_len - 1)
> +				writel(out[0], master->regs + NPCM_I3C_MWDATABE);
> +			else
> +				writel(out[0], master->regs + NPCM_I3C_MWDATAB);
> +			out++;
> +		}
> +		xfer_len -= count;
> +	}
> +
> +	if (use_dma) {
> +		if (xfer_len > MAX_DMA_COUNT) {
> +			dev_err(master->dev, "data is larger than buffer size (%d)\n",
> +				MAX_DMA_COUNT);
> +			spin_unlock_irqrestore(&master->req_lock, flags);
> +			npcm_i3c_master_dma_unlock();
> +			return -EINVAL;
> +		}
> +		master->dma_xfer.out = out;
> +		master->dma_xfer.in = in;
> +		master->dma_xfer.len = xfer_len;
> +		master->dma_xfer.rnw = rnw;
> +		master->dma_xfer.end = !continued;
> +		init_completion(&master->xfer_comp);
> +	}
> +
> +	start = jiffies;
> +
> +broadcast_start:
> +	if (first && rnw) {
> +		/* Send 7E first to avoid collision during master read */
> +		ret = npcm_i3c_send_broadcast(master);
> +		if (ret < 0) {
> +			dev_err(master->dev, "send 7e error\n");
> +			goto emit_stop;
> +		}
> +		if (time_after(jiffies, start + msecs_to_jiffies(1000))) {
> +			dev_err(master->dev, "abnormal ibiwon events\n");
> +			goto emit_stop;
> +		}
> +		if (ret > 0)
> +			goto broadcast_start;
> +	}
> +
> +	if (rnw) {
> +		ibiresp = NPCM_I3C_MCTRL_IBIRESP_NACK;
> +		npcm_i3c_master_set_sda_skew(master,
> +				master->scl_timing.i3c_pp_sda_rd_skew);
> +	} else {
> +		ibiresp = NPCM_I3C_MCTRL_IBIRESP_AUTO;
> +		npcm_i3c_master_set_sda_skew(master,
> +				master->scl_timing.i3c_pp_sda_wr_skew);
> +	}
> +
> +	if (use_dma)
> +		npcm_i3c_master_start_dma(master);
> +
> +retry_start:
> +	writel(NPCM_I3C_MCTRL_REQUEST_START_ADDR |
> +	       xfer_type |
> +	       ibiresp |
> +	       NPCM_I3C_MCTRL_DIR(rnw) |
> +	       NPCM_I3C_MCTRL_ADDR(addr) |
> +	       NPCM_I3C_MCTRL_RDTERM(rdterm),
> +	       master->regs + NPCM_I3C_MCTRL);
> +
> +	ret = readl_poll_timeout(master->regs + NPCM_I3C_MSTATUS, reg,
> +				 NPCM_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
> +	if (ret) {
> +		dev_err(master->dev, "xfer (%d) wait ctrl-done timeout, mstatus=0x%02x\n",
> +			rnw, reg);
> +		goto emit_stop;
> +	}
> +
> +	mstatus = readl(master->regs + NPCM_I3C_MSTATUS);
> +	if (NPCM_I3C_MSTATUS_IBIWON(mstatus)) {
> +		if (rnw) {
> +			dev_err(master->dev, "xfer read: re-start but ibiwon, mstatus=0x%02x\n",
> +					mstatus);
> +			ret = -EIO;
> +			goto emit_stop;
> +		}
> +
> +		ret = npcm_i3c_master_handle_ibiwon(master, true);
> +		if (ret) {
> +			dev_err(master->dev, "xfer read: handle ibi event fail, ret=%d\n", ret);
> +			goto emit_stop;
> +		}
> +
> +		if (time_after(jiffies, start + msecs_to_jiffies(1000))) {
> +			dev_err(master->dev, "abnormal ibiwon events\n");
> +			goto emit_stop;
> +		}
> +
> +		/* Clear COMPLETE status of this IBI transaction */
> +		writel(NPCM_I3C_MINT_COMPLETE, master->regs + NPCM_I3C_MSTATUS);
> +		goto retry_start;
> +	}
> +
> +	/* Use COMPLETE interrupt as notification of transfer completion */
> +	if (use_dma)
> +		npcm_i3c_master_enable_interrupts(master, NPCM_I3C_MINT_COMPLETE);
> +
> +	bus_locked = false;
> +	spin_unlock_irqrestore(&master->req_lock, flags);
> +
> +	reg = readl(master->regs + NPCM_I3C_MSTATUS);
> +	if (NPCM_I3C_MSTATUS_NACKED(reg)) {
> +		dev_dbg(master->dev, "addr 0x%x NACK\n", addr);
> +		ret = -EIO;
> +		goto emit_stop;
> +	}
> +
> +	if (use_dma)
> +		ret = npcm_i3c_master_wait_for_complete(master);
> +	else if (rnw)
> +		ret = npcm_i3c_master_read(master, in, xfer_len);
> +	else
> +		ret = npcm_i3c_master_write(master, out, xfer_len);
> +	if (ret < 0)
> +		goto emit_stop;
> +
> +	if (rnw)
> +		*read_len = ret;
> +
> +	if (!use_dma) {
> +		ret = readl_poll_timeout(master->regs + NPCM_I3C_MSTATUS, reg,
> +					 NPCM_I3C_MSTATUS_COMPLETE(reg), 0, 1000);
> +		if (ret)
> +			goto emit_stop;
> +
> +		/* If use_dma, COMPLETE bit is cleared in the isr */
> +		writel(NPCM_I3C_MINT_COMPLETE, master->regs + NPCM_I3C_MSTATUS);
> +	}
> +
> +
> +	if (!continued && !use_dma) {
> +		npcm_i3c_master_set_sda_skew(master, 0);
> +		npcm_i3c_master_emit_stop(master);
> +	}
> +
> +	if (!use_dma)
> +		local_irq_enable();
> +	else
> +		npcm_i3c_master_dma_unlock();
> +
> +	return 0;
> +
> +emit_stop:
> +	if (use_dma)
> +		npcm_i3c_master_stop_dma(master);
> +
> +	if (bus_locked)
> +		spin_unlock_irqrestore(&master->req_lock, flags);
> +
> +	spin_lock_irqsave(&master->req_lock, flags);
> +
> +	npcm_i3c_master_set_sda_skew(master, 0);
> +
> +	reg = readl(master->regs + NPCM_I3C_MSTATUS);
> +	npcm_i3c_master_emit_stop(master);
> +	npcm_i3c_master_clear_merrwarn(master);
> +	npcm_i3c_master_flush_fifo(master);
> +	spin_unlock_irqrestore(&master->req_lock, flags);
> +
> +	if (!use_dma)
> +		local_irq_enable();
> +	else
> +		npcm_i3c_master_dma_unlock();
> +
> +	return ret;
> +}
> +
> +static struct npcm_i3c_xfer *
> +npcm_i3c_master_alloc_xfer(struct npcm_i3c_master *master, unsigned int ncmds)
> +{
> +	struct npcm_i3c_xfer *xfer;
> +
> +	xfer = kzalloc(struct_size(xfer, cmds, ncmds), GFP_KERNEL);
> +	if (!xfer)
> +		return NULL;
> +
> +	INIT_LIST_HEAD(&xfer->node);
> +	xfer->ncmds = ncmds;
> +	xfer->ret = -ETIMEDOUT;
> +
> +	return xfer;
> +}
> +
> +static void npcm_i3c_master_free_xfer(struct npcm_i3c_xfer *xfer)
> +{
> +	kfree(xfer);
> +}
> +
> +static void npcm_i3c_master_dequeue_xfer_locked(struct npcm_i3c_master *master,
> +					       struct npcm_i3c_xfer *xfer)
> +{
> +	if (master->xferqueue.cur == xfer)
> +		master->xferqueue.cur = NULL;
> +	else
> +		list_del_init(&xfer->node);
> +}
> +
> +static void npcm_i3c_master_dequeue_xfer(struct npcm_i3c_master *master,
> +					struct npcm_i3c_xfer *xfer)
> +{
> +	npcm_i3c_master_dequeue_xfer_locked(master, xfer);
> +}
> +
> +static void npcm_i3c_master_start_xfer_locked(struct npcm_i3c_master *master)
> +{
> +	struct npcm_i3c_xfer *xfer = master->xferqueue.cur;
> +	unsigned long flags;
> +	int ret, i;
> +
> +	if (!xfer)
> +		return;
> +
> +	/* Prevent fifo flush while IBI isr is running */
> +	spin_lock_irqsave(&master->req_lock, flags);
> +	npcm_i3c_master_clear_merrwarn(master);
> +	npcm_i3c_master_flush_fifo(master);
> +	spin_unlock_irqrestore(&master->req_lock, flags);
> +
> +	for (i = 0; i < xfer->ncmds; i++) {
> +		struct npcm_i3c_cmd *cmd = &xfer->cmds[i];
> +
> +		ret = npcm_i3c_master_xfer(master, cmd->rnw, xfer->type,
> +					  cmd->addr, cmd->in, cmd->out,
> +					  cmd->len, &cmd->read_len,
> +					  cmd->continued, cmd->use_dma, (i == 0));
> +		if (ret)
> +			break;
> +	}
> +
> +	xfer->ret = ret;
> +	complete(&xfer->comp);
> +
> +	if (ret < 0)
> +		npcm_i3c_master_dequeue_xfer_locked(master, xfer);
> +
> +	xfer = list_first_entry_or_null(&master->xferqueue.list,
> +					struct npcm_i3c_xfer,
> +					node);
> +	if (xfer)
> +		list_del_init(&xfer->node);
> +
> +	master->xferqueue.cur = xfer;
> +	npcm_i3c_master_start_xfer_locked(master);
> +}
> +
> +static void npcm_i3c_master_enqueue_xfer(struct npcm_i3c_master *master,
> +					struct npcm_i3c_xfer *xfer)
> +{
> +	init_completion(&xfer->comp);
> +	if (master->xferqueue.cur) {
> +		list_add_tail(&xfer->node, &master->xferqueue.list);
> +	} else {
> +		master->xferqueue.cur = xfer;
> +		npcm_i3c_master_start_xfer_locked(master);
> +	}
> +}
> +
> +static bool
> +npcm_i3c_master_supports_ccc_cmd(struct i3c_master_controller *master,
> +				const struct i3c_ccc_cmd *cmd)
> +{
> +	/* No software support for CCC commands targeting more than one slave */
> +	return (cmd->ndests == 1);
> +}
> +
> +static int npcm_i3c_master_send_bdcast_ccc_cmd(struct npcm_i3c_master *master,
> +					      struct i3c_ccc_cmd *ccc)
> +{
> +	unsigned int xfer_len = ccc->dests[0].payload.len + 1;
> +	struct npcm_i3c_xfer *xfer;
> +	struct npcm_i3c_cmd *cmd;
> +	u8 *buf;
> +	int ret;
> +
> +	xfer = npcm_i3c_master_alloc_xfer(master, 1);
> +	if (!xfer)
> +		return -ENOMEM;
> +
> +	buf = kmalloc(xfer_len, GFP_KERNEL);
> +	if (!buf) {
> +		npcm_i3c_master_free_xfer(xfer);
> +		return -ENOMEM;
> +	}
> +
> +	buf[0] = ccc->id;
> +	memcpy(&buf[1], ccc->dests[0].payload.data, ccc->dests[0].payload.len);
> +
> +	xfer->type = NPCM_I3C_MCTRL_TYPE_I3C;
> +
> +	cmd = &xfer->cmds[0];
> +	cmd->addr = ccc->dests[0].addr;
> +	cmd->rnw = ccc->rnw;
> +	cmd->in = NULL;
> +	cmd->out = buf;
> +	cmd->len = xfer_len;
> +	cmd->read_len = 0;
> +	cmd->continued = false;
> +
> +	mutex_lock(&master->lock);
> +	npcm_i3c_master_enqueue_xfer(master, xfer);
> +	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
> +		npcm_i3c_master_dequeue_xfer(master, xfer);
> +	mutex_unlock(&master->lock);
> +
> +	ret = xfer->ret;
> +	kfree(buf);
> +	npcm_i3c_master_free_xfer(xfer);
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_send_direct_ccc_cmd(struct npcm_i3c_master *master,
> +					      struct i3c_ccc_cmd *ccc)
> +{
> +	unsigned int xfer_len = ccc->dests[0].payload.len;
> +	unsigned int read_len = ccc->rnw ? xfer_len : 0;
> +	struct npcm_i3c_xfer *xfer;
> +	struct npcm_i3c_cmd *cmd;
> +	int ret;
> +
> +	xfer = npcm_i3c_master_alloc_xfer(master, 2);
> +	if (!xfer)
> +		return -ENOMEM;
> +
> +	xfer->type = NPCM_I3C_MCTRL_TYPE_I3C;
> +
> +	/* Broadcasted message */
> +	cmd = &xfer->cmds[0];
> +	cmd->addr = I3C_BROADCAST_ADDR;
> +	cmd->rnw = 0;
> +	cmd->in = NULL;
> +	cmd->out = &ccc->id;
> +	cmd->len = 1;
> +	cmd->read_len = 0;
> +	cmd->continued = true;
> +
> +	/* Directed message */
> +	cmd = &xfer->cmds[1];
> +	cmd->addr = ccc->dests[0].addr;
> +	cmd->rnw = ccc->rnw;
> +	cmd->in = ccc->rnw ? ccc->dests[0].payload.data : NULL;
> +	cmd->out = ccc->rnw ? NULL : ccc->dests[0].payload.data,
> +	cmd->len = xfer_len;
> +	cmd->read_len = read_len;
> +	cmd->continued = false;
> +
> +	mutex_lock(&master->lock);
> +	npcm_i3c_master_enqueue_xfer(master, xfer);
> +	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
> +		npcm_i3c_master_dequeue_xfer(master, xfer);
> +	mutex_unlock(&master->lock);
> +
> +	if (cmd->read_len != xfer_len)
> +		ccc->dests[0].payload.len = cmd->read_len;
> +
> +	ret = xfer->ret;
> +	npcm_i3c_master_free_xfer(xfer);
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_send_ccc_cmd(struct i3c_master_controller *m,
> +				       struct i3c_ccc_cmd *cmd)
> +{
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	bool broadcast = cmd->id < 0x80;
> +	int ret;
> +
> +	if (broadcast)
> +		ret = npcm_i3c_master_send_bdcast_ccc_cmd(master, cmd);
> +	else
> +		ret = npcm_i3c_master_send_direct_ccc_cmd(master, cmd);
> +
> +	if (ret) {
> +		dev_dbg(master->dev, "send ccc 0x%02x %s, ret = %d\n",
> +				cmd->id, broadcast ? "(broadcast)" : "", ret);
> +		cmd->err = I3C_ERROR_M2;
> +	}
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_priv_xfers(struct i3c_dev_desc *dev,
> +				     struct i3c_priv_xfer *xfers,
> +				     int nxfers)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +	struct npcm_i3c_xfer *xfer;
> +	int ret, i;
> +
> +	xfer = npcm_i3c_master_alloc_xfer(master, nxfers);
> +	if (!xfer)
> +		return -ENOMEM;
> +
> +	xfer->type = NPCM_I3C_MCTRL_TYPE_I3C;
> +
> +	for (i = 0; i < nxfers; i++) {
> +		struct npcm_i3c_cmd *cmd = &xfer->cmds[i];
> +
> +		cmd->addr = master->addrs[data->index];
> +		cmd->rnw = xfers[i].rnw;
> +		cmd->in = xfers[i].rnw ? xfers[i].data.in : NULL;
> +		cmd->out = xfers[i].rnw ? NULL : xfers[i].data.out;
> +		cmd->len = xfers[i].len;
> +		cmd->read_len = xfers[i].rnw ? xfers[i].len : 0;
> +		cmd->continued = (i + 1) < nxfers;
> +		if (master->use_dma && xfers[i].len > 1)
> +			cmd->use_dma = true;
> +	}
> +
> +	mutex_lock(&master->lock);
> +	npcm_i3c_master_enqueue_xfer(master, xfer);
> +	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
> +		npcm_i3c_master_dequeue_xfer(master, xfer);
> +	mutex_unlock(&master->lock);
> +
> +	for (i = 0; i < nxfers; i++) {
> +		struct npcm_i3c_cmd *cmd = &xfer->cmds[i];
> +
> +		if (xfers[i].rnw)
> +			xfers[i].len = cmd->read_len;
> +	}
> +	ret = xfer->ret;
> +	npcm_i3c_master_free_xfer(xfer);
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_i2c_xfers(struct i2c_dev_desc *dev,
> +				    const struct i2c_msg *xfers,
> +				    int nxfers)
> +{
> +	struct i3c_master_controller *m = i2c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
> +	struct npcm_i3c_xfer *xfer;
> +	int ret, i;
> +
> +	xfer = npcm_i3c_master_alloc_xfer(master, nxfers);
> +	if (!xfer)
> +		return -ENOMEM;
> +
> +	xfer->type = NPCM_I3C_MCTRL_TYPE_I2C;
> +
> +	for (i = 0; i < nxfers; i++) {
> +		struct npcm_i3c_cmd *cmd = &xfer->cmds[i];
> +
> +		cmd->addr = master->addrs[data->index];
> +		cmd->rnw = xfers[i].flags & I2C_M_RD;
> +		cmd->in = cmd->rnw ? xfers[i].buf : NULL;
> +		cmd->out = cmd->rnw ? NULL : xfers[i].buf;
> +		cmd->len = xfers[i].len;
> +		cmd->read_len = cmd->rnw ? xfers[i].len : 0;
> +		cmd->continued = (i + 1 < nxfers);
> +	}
> +
> +	mutex_lock(&master->lock);
> +	npcm_i3c_master_enqueue_xfer(master, xfer);
> +	if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
> +		npcm_i3c_master_dequeue_xfer(master, xfer);
> +	mutex_unlock(&master->lock);
> +
> +	ret = xfer->ret;
> +	npcm_i3c_master_free_xfer(xfer);
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_request_ibi(struct i3c_dev_desc *dev,
> +				      const struct i3c_ibi_setup *req)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +	unsigned long flags;
> +	unsigned int i;
> +	struct i3c_ibi_setup ibi_req;
> +
> +	if (dev->ibi->max_payload_len > NPCM_I3C_MAX_IBI_PAYLOAD_SIZE) {
> +		dev_err(master->dev, "IBI max payload %d should be < %d\n",
> +			dev->ibi->max_payload_len, NPCM_I3C_MAX_IBI_PAYLOAD_SIZE + 1);
> +		return -ERANGE;
> +	}
> +
> +	memcpy(&ibi_req, req, sizeof(struct i3c_ibi_setup));
> +	ibi_req.max_payload_len = NPCM_I3C_MAX_IBI_PAYLOAD_SIZE;
> +	data->ibi_pool = i3c_generic_ibi_alloc_pool(dev, &ibi_req);
> +	if (IS_ERR(data->ibi_pool))
> +		return PTR_ERR(data->ibi_pool);
> +
> +	spin_lock_irqsave(&master->ibi.lock, flags);
> +	for (i = 0; i < master->ibi.num_slots; i++) {
> +		if (!master->ibi.slots[i]) {
> +			data->ibi = i;
> +			master->ibi.slots[i] = dev;
> +			break;
> +		}
> +	}
> +	spin_unlock_irqrestore(&master->ibi.lock, flags);
> +
> +	if (i < master->ibi.num_slots)
> +		return 0;
> +
> +	i3c_generic_ibi_free_pool(data->ibi_pool);
> +	data->ibi_pool = NULL;
> +
> +	return -ENOSPC;
> +}
> +
> +static void npcm_i3c_master_free_ibi(struct i3c_dev_desc *dev)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +	unsigned long flags;
> +
> +	spin_lock_irqsave(&master->ibi.lock, flags);
> +	master->ibi.slots[data->ibi] = NULL;
> +	data->ibi = -1;
> +	spin_unlock_irqrestore(&master->ibi.lock, flags);
> +
> +	i3c_generic_ibi_free_pool(data->ibi_pool);
> +}
> +
> +static int npcm_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +
> +	/* Clear the interrupt status */
> +	writel(NPCM_I3C_MINT_SLVSTART, master->regs + NPCM_I3C_MSTATUS);
> +	npcm_i3c_master_enable_interrupts(master, NPCM_I3C_MINT_SLVSTART);
> +
> +	return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
> +}
> +
> +static int npcm_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
> +{
> +	struct i3c_master_controller *m = i3c_dev_get_master(dev);
> +	struct npcm_i3c_master *master = to_npcm_i3c_master(m);
> +	int ret;
> +
> +	writel(NPCM_I3C_MINT_SLVSTART, master->regs + NPCM_I3C_MINTCLR);
> +
> +	ret = i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
> +
> +	return ret;
> +}
> +
> +static void npcm_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
> +					    struct i3c_ibi_slot *slot)
> +{
> +	struct npcm_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
> +
> +	i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);
> +}
> +
> +static const struct i3c_master_controller_ops npcm_i3c_master_ops = {
> +	.bus_init = npcm_i3c_master_bus_init,
> +	.bus_cleanup = npcm_i3c_master_bus_cleanup,
> +	.attach_i3c_dev = npcm_i3c_master_attach_i3c_dev,
> +	.detach_i3c_dev = npcm_i3c_master_detach_i3c_dev,
> +	.reattach_i3c_dev = npcm_i3c_master_reattach_i3c_dev,
> +	.attach_i2c_dev = npcm_i3c_master_attach_i2c_dev,
> +	.detach_i2c_dev = npcm_i3c_master_detach_i2c_dev,
> +	.do_daa = npcm_i3c_master_do_daa,
> +	.supports_ccc_cmd = npcm_i3c_master_supports_ccc_cmd,
> +	.send_ccc_cmd = npcm_i3c_master_send_ccc_cmd,
> +	.priv_xfers = npcm_i3c_master_priv_xfers,
> +	.i2c_xfers = npcm_i3c_master_i2c_xfers,
> +	.request_ibi = npcm_i3c_master_request_ibi,
> +	.free_ibi = npcm_i3c_master_free_ibi,
> +	.recycle_ibi_slot = npcm_i3c_master_recycle_ibi_slot,
> +	.enable_ibi = npcm_i3c_master_enable_ibi,
> +	.disable_ibi = npcm_i3c_master_disable_ibi,
> +};
> +
> +static int npcm_i3c_master_prepare_clks(struct npcm_i3c_master *master)
> +{
> +	int ret = 0;
> +
> +	ret = clk_prepare_enable(master->pclk);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_prepare_enable(master->fclk);
> +	if (ret) {
> +		clk_disable_unprepare(master->pclk);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void npcm_i3c_master_unprepare_clks(struct npcm_i3c_master *master)
> +{
> +	clk_disable_unprepare(master->pclk);
> +	clk_disable_unprepare(master->fclk);
> +}
> +
> +static struct dentry *npcm_i3c_debugfs_dir;
> +static int debug_show(struct seq_file *seq, void *v)
> +{
> +	struct npcm_i3c_master *master = seq->private;
> +
> +	seq_printf(seq, "MSTATUS=0x%x\n", readl(master->regs + NPCM_I3C_MSTATUS));
> +	seq_printf(seq, "MERRWARN=0x%x\n", readl(master->regs + NPCM_I3C_MERRWARN));
> +	seq_printf(seq, "MCTRL=0x%x\n", readl(master->regs + NPCM_I3C_MCTRL));
> +	seq_printf(seq, "MDATACTRL=0x%x\n", readl(master->regs + NPCM_I3C_MDATACTRL));
> +	seq_printf(seq, "MCONFIG=0x%x\n", readl(master->regs + NPCM_I3C_MCONFIG));
> +
> +	return 0;
> +}
> +
> +DEFINE_SHOW_ATTRIBUTE(debug);
> +
> +static void npcm_i3c_init_debugfs(struct platform_device *pdev,
> +				 struct npcm_i3c_master *master)
> +{
> +	if (!npcm_i3c_debugfs_dir) {
> +		npcm_i3c_debugfs_dir = debugfs_create_dir("npcm_i3c", NULL);
> +		if (!npcm_i3c_debugfs_dir)
> +			return;
> +	}
> +
> +	master->debugfs = debugfs_create_dir(dev_name(&pdev->dev),
> +					     npcm_i3c_debugfs_dir);
> +	if (!master->debugfs)
> +		return;
> +
> +	debugfs_create_file("debug", 0444, master->debugfs, master, &debug_fops);
> +}
> +
> +static int npcm_i3c_setup_dma(struct platform_device *pdev, struct npcm_i3c_master *master)
> +{
> +	struct device *dev = &pdev->dev;
> +	u32 dma_conn, dma_ctl, reg_base;
> +
> +	if (!of_property_read_bool(dev->of_node, "use-dma"))
> +		return 0;
> +
> +	master->dma_regs = devm_platform_ioremap_resource_byname(pdev, "dma");
> +	if (IS_ERR(master->dma_regs))
> +		return 0;
> +
> +	master->dma_ctl_regs = devm_platform_ioremap_resource_byname(pdev, "dma_ctl");
> +	if (IS_ERR(master->dma_ctl_regs))
> +		return 0;
> +
> +	/* DMA TX transfer width is 32 bits(MWDATAB width) for each byte sent to I3C bus */
> +	master->dma_tx_buf = dma_alloc_coherent(dev, MAX_DMA_COUNT * 4,
> +						&master->dma_tx_addr, GFP_KERNEL);
> +	if (!master->dma_tx_buf)
> +		return -ENOMEM;
> +
> +	master->dma_rx_buf = dma_alloc_coherent(dev, MAX_DMA_COUNT,
> +						&master->dma_rx_addr, GFP_KERNEL);
> +	if (!master->dma_rx_buf) {
> +		dma_free_coherent(master->dev, MAX_DMA_COUNT * 4, master->dma_tx_buf,
> +				  master->dma_tx_addr);
> +		return -ENOMEM;
> +	}
> +
> +	/*
> +	 * Set DMA channel connectivity
> +	 * channel 0: I3C TX, channel 1: I3C RX
> +	 */
> +	of_property_read_u32_index(dev->of_node, "reg", 0, &reg_base);
> +	dma_conn = NPCM_GDMA_MUX(reg_base);
> +	dma_ctl = GDMA_CH0_EN | GDMA_CH1_EN | (dma_conn + 1) << 16 | dma_conn;
> +	writel(dma_ctl, master->dma_ctl_regs);
> +	master->use_dma = true;
> +	dev_info(dev, "Using DMA (req_sel %d)\n", dma_conn);
> +
> +	/*
> +	 * Setup GDMA Channel for TX (Memory to I3C FIFO)
> +	 */
> +	writel(master->dma_tx_addr, master->dma_regs + NPCM_GDMA_SRCB(DMA_CH_TX));
> +	writel(reg_base + NPCM_I3C_MWDATAB, master->dma_regs +
> +	       NPCM_GDMA_DSTB(DMA_CH_TX));
> +	/*
> +	 * Setup GDMA Channel for RX (I3C FIFO to Memory)
> +	 */
> +	writel(reg_base + NPCM_I3C_MRDATAB, master->dma_regs +
> +	       NPCM_GDMA_SRCB(DMA_CH_RX));
> +	writel(master->dma_rx_addr, master->dma_regs + NPCM_GDMA_DSTB(DMA_CH_RX));
> +
> +	return 0;
> +}
> +
> +static int npcm_i3c_master_probe(struct platform_device *pdev)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct npcm_i3c_master *master;
> +	struct reset_control *reset;
> +	u32 val;
> +	int ret;
> +
> +	master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
> +	if (!master)
> +		return -ENOMEM;
> +
> +	master->regs = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(master->regs))
> +		return PTR_ERR(master->regs);
> +
> +	master->pclk = devm_clk_get(dev, "pclk");
> +	if (IS_ERR(master->pclk))
> +		return PTR_ERR(master->pclk);
> +
> +	master->fclk = devm_clk_get(dev, "fast_clk");
> +	if (IS_ERR(master->fclk))
> +		return PTR_ERR(master->fclk);
> +
> +	master->irq = platform_get_irq(pdev, 0);
> +	if (master->irq < 0)
> +		return master->irq;
> +
> +	master->dev = dev;
> +
> +	ret = npcm_i3c_master_prepare_clks(master);
> +	if (ret)
> +		return ret;
> +
> +	reset = devm_reset_control_get(&pdev->dev, NULL);
> +	if (!IS_ERR(reset)) {
> +		reset_control_assert(reset);
> +		udelay(5);
> +		reset_control_deassert(reset);
> +	}
> +	INIT_WORK(&master->hj_work, npcm_i3c_master_hj_work);
> +	ret = devm_request_irq(dev, master->irq, npcm_i3c_master_irq_handler,
> +			       IRQF_NO_SUSPEND, "npcm-i3c-irq", master);
> +	if (ret)
> +		goto err_disable_clks;
> +
> +	master->free_slots = GENMASK(NPCM_I3C_MAX_DEVS - 1, 0);
> +
> +	mutex_init(&master->lock);
> +	INIT_LIST_HEAD(&master->xferqueue.list);
> +
> +	spin_lock_init(&master->req_lock);
> +	spin_lock_init(&master->ibi.lock);
> +	master->ibi.num_slots = NPCM_I3C_MAX_DEVS;
> +	master->ibi.slots = devm_kcalloc(&pdev->dev, master->ibi.num_slots,
> +					 sizeof(*master->ibi.slots),
> +					 GFP_KERNEL);
> +	if (!master->ibi.slots) {
> +		ret = -ENOMEM;
> +		goto err_disable_clks;
> +	}
> +
> +	platform_set_drvdata(pdev, master);
> +
> +	npcm_i3c_master_reset(master);
> +
> +	if (of_property_read_bool(dev->of_node, "enable-hj"))
> +		master->en_hj = true;
> +	if (!of_property_read_u32(dev->of_node, "i3c-pp-scl-hi-period-ns", &val))
> +		master->scl_timing.i3c_pp_hi = val;
> +
> +	if (!of_property_read_u32(dev->of_node, "i3c-pp-scl-lo-period-ns", &val))
> +		master->scl_timing.i3c_pp_lo = val;
> +
> +	if (!of_property_read_u32(dev->of_node, "i3c-pp-sda-rd-skew", &val))
> +		master->scl_timing.i3c_pp_sda_rd_skew = val;
> +
> +	if (!of_property_read_u32(dev->of_node, "i3c-pp-sda-wr-skew", &val))
> +		master->scl_timing.i3c_pp_sda_wr_skew = val;
> +
> +	if (!of_property_read_u32(dev->of_node, "i3c-od-scl-hi-period-ns", &val))
> +		master->scl_timing.i3c_od_hi = val;
> +
> +	if (!of_property_read_u32(dev->of_node, "i3c-od-scl-lo-period-ns", &val))
> +		master->scl_timing.i3c_od_lo = val;
> +
> +	npcm_i3c_master_clear_merrwarn(master);
> +	npcm_i3c_master_flush_fifo(master);
> +
> +	ret = npcm_i3c_setup_dma(pdev, master);
> +	if (ret)
> +		goto err_disable_clks;
> +
> +	npcm_i3c_init_debugfs(pdev, master);
> +
> +	/* Register the master */
> +	ret = i3c_master_register(&master->base, &pdev->dev,
> +				  &npcm_i3c_master_ops, false);
> +	if (ret)
> +		goto err_disable_clks;
> +
> +	if (master->en_hj) {
> +		dev_info(master->dev, "enable hot-join\n");
> +		npcm_i3c_master_enable_interrupts(master, NPCM_I3C_MINT_SLVSTART);
> +	}
> +	return 0;
> +
> +	debugfs_remove_recursive(master->debugfs);
> +
> +err_disable_clks:
> +	npcm_i3c_master_unprepare_clks(master);
> +
> +	return ret;
> +}
> +
> +static int npcm_i3c_master_remove(struct platform_device *pdev)
> +{
> +	struct npcm_i3c_master *master = platform_get_drvdata(pdev);
> +
> +	/* Avoid ibi events during driver unbinding */
> +	writel(NPCM_I3C_MINT_SLVSTART, master->regs + NPCM_I3C_MINTCLR);
> +
> +	debugfs_remove_recursive(master->debugfs);
> +
> +	i3c_master_unregister(&master->base);
> +
> +	if (master->use_dma) {
> +		dma_free_coherent(master->dev, MAX_DMA_COUNT * 4, master->dma_tx_buf,
> +				  master->dma_tx_addr);
> +		dma_free_coherent(master->dev, MAX_DMA_COUNT, master->dma_rx_buf,
> +				  master->dma_rx_addr);
> +	}
> +	return 0;
> +}
> +
> +static const struct of_device_id npcm_i3c_master_of_match_tbl[] = {
> +	{ .compatible = "nuvoton,npcm845-i3c" },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, npcm_i3c_master_of_match_tbl);
> +
> +static struct platform_driver npcm_i3c_master = {
> +	.probe = npcm_i3c_master_probe,
> +	.remove = npcm_i3c_master_remove,
> +	.driver = {
> +		.name = "npcm845-i3c-master",
> +		.of_match_table = npcm_i3c_master_of_match_tbl,
> +	},
> +};
> +module_platform_driver(npcm_i3c_master);
> +
> +MODULE_AUTHOR("Stanley Chu <yschu at nuvoton.com>");
> +MODULE_AUTHOR("James Chiang <cpchiang1 at nuvoton.com>");
> +MODULE_DESCRIPTION("Nuvoton NPCM845 I3C master driver");
> +MODULE_LICENSE("GPL");
> --
> 2.34.1
>


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