[PATCH v9 2/2] i2c: aspeed: support ast2600 i2c new register mode driver

csf0711 at gmail.com csf0711 at gmail.com
Tue Apr 11 12:24:25 AEST 2023


> Add i2c new register mode driver to support AST2600 i2c
> new register mode. AST2600 i2c controller have legacy and
> new register mode. The new register mode have global register
> support 4 base clock for scl clock selection, and new clock
> divider mode. The i2c new register mode have separate register
> set to control i2c master and slave.
> 
> Signed-off-by: Ryan Chen <ryan_chen at aspeedtech.com>

Tested-by: Brian Chen <csf0711 at gmail.com>

> ---
>  MAINTAINERS                      |    9 +
>  drivers/i2c/busses/Kconfig       |   11 +
>  drivers/i2c/busses/Makefile      |    1 +
>  drivers/i2c/busses/i2c-ast2600.c | 1602 ++++++++++++++++++++++++++++++
>  4 files changed, 1623 insertions(+)
>  create mode 100644 drivers/i2c/busses/i2c-ast2600.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 749710e22b4d..433ec2309441 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -1924,6 +1924,15 @@ F:
>
Documentation/devicetree/bindings/interrupt-controller/aspeed,ast2400-
> i2c-ic.
>  F:	drivers/i2c/busses/i2c-aspeed.c
>  F:	drivers/irqchip/irq-aspeed-i2c-ic.c
> 
> +ARM/ASPEED I2CV2 DRIVER
> +M:	Ryan Chen <ryan_chen at aspeedtech.com>
> +R:	Andrew Jeffery <andrew at aj.id.au>
> +L:	linux-i2c at vger.kernel.org
> +L:	openbmc at lists.ozlabs.org (moderated for non-subscribers)
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
> +F:	drivers/i2c/busses/i2c-ast2600.c
> +
>  ARM/ASPEED MACHINE SUPPORT
>  M:	Joel Stanley <joel at jms.id.au>
>  R:	Andrew Jeffery <andrew at aj.id.au>
> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
> index 7284206b278b..4f6935866257 100644
> --- a/drivers/i2c/busses/Kconfig
> +++ b/drivers/i2c/busses/Kconfig
> @@ -389,6 +389,17 @@ config I2C_ALTERA
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called i2c-altera.
> 
> +config I2C_AST2600
> +	tristate "Aspeed I2C v2 Controller"
> +	depends on ARCH_ASPEED || COMPILE_TEST
> +	select I2C_SMBUS
> +	help
> +	  If you say yes to this option, support will be included for the
> +	  Aspeed I2C controller with new register set.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called i2c-ast2600.
> +
>  config I2C_ASPEED
>  	tristate "Aspeed I2C Controller"
>  	depends on ARCH_ASPEED || COMPILE_TEST
> diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
> index c5cac15f075c..d0ab4d45781c 100644
> --- a/drivers/i2c/busses/Makefile
> +++ b/drivers/i2c/busses/Makefile
> @@ -38,6 +38,7 @@ obj-$(CONFIG_I2C_POWERMAC)	+= i2c-powermac.o
>  obj-$(CONFIG_I2C_ALTERA)	+= i2c-altera.o
>  obj-$(CONFIG_I2C_AMD_MP2)	+= i2c-amd-mp2-pci.o i2c-amd-mp2-plat.o
>  obj-$(CONFIG_I2C_ASPEED)	+= i2c-aspeed.o
> +obj-$(CONFIG_I2C_AST2600)	+= i2c-ast2600.o
>  obj-$(CONFIG_I2C_AT91)		+= i2c-at91.o
>  i2c-at91-objs			:= i2c-at91-core.o i2c-at91-master.o
>  ifeq ($(CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL),y)
> diff --git a/drivers/i2c/busses/i2c-ast2600.c
b/drivers/i2c/busses/i2c-ast2600.c
> new file mode 100644
> index 000000000000..c8817fe9b23f
> --- /dev/null
> +++ b/drivers/i2c/busses/i2c-ast2600.c
> @@ -0,0 +1,1602 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * ASPEED AST2600 new register set I2C controller driver
> + *
> + * Copyright (C) ASPEED Technology Inc.
> + */
> +#include <linux/clk.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/io.h>
> +#include <linux/slab.h>
> +#include <linux/delay.h>
> +#include <linux/reset.h>
> +#include <linux/module.h>
> +#include <linux/interrupt.h>
> +#include <linux/completion.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/regmap.h>
> +#include <linux/of_device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/i2c-smbus.h>
> +
> +/*
> + * APB clk : 100Mhz
> + * div	: scl		: baseclk [APB/((div/2) + 1)] : tBuf [1/bclk
* 16]
> + * I2CG10[31:24] base clk4 for i2c auto recovery timeout counter (0xC6)
> + * I2CG10[23:16] base clk3 for Standard-mode (100Khz) min tBuf 4.7us
> + * 0x3c : 100.8Khz	: 3.225Mhz					  :
4.96us
> + * 0x3d : 99.2Khz	: 3.174Mhz					  :
5.04us
> + * 0x3e : 97.65Khz	: 3.125Mhz					  :
5.12us
> + * 0x40 : 97.75Khz	: 3.03Mhz					  :
5.28us
> + * 0x41 : 99.5Khz	: 2.98Mhz					  :
5.36us (default)
> + * I2CG10[15:8] base clk2 for Fast-mode (400Khz) min tBuf 1.3us
> + * 0x12 : 400Khz	: 10Mhz						  :
1.6us
> + * I2CG10[7:0] base clk1 for Fast-mode Plus (1Mhz) min tBuf 0.5us
> + * 0x08 : 1Mhz		: 20Mhz
: 0.8us
> + */
> +#define AST2600_I2CG_ISR			0x00
> +#define AST2600_I2CG_SLAVE_ISR		0x04
> +#define AST2600_I2CG_OWNER		0x08
> +#define AST2600_I2CG_CTRL		0x0C
> +#define AST2600_I2CG_CLK_DIV_CTRL	0x10
> +
> +#define AST2600_I2CG_SLAVE_PKT_NAK	BIT(4)
> +#define AST2600_I2CG_M_S_SEPARATE_INTR	BIT(3)
> +#define AST2600_I2CG_CTRL_NEW_REG	BIT(2)
> +#define AST2600_I2CG_CTRL_NEW_CLK_DIV	BIT(1)
> +
> +#define AST2600_GLOBAL_INIT				\
> +			(AST2600_I2CG_CTRL_NEW_REG |	\
> +			AST2600_I2CG_CTRL_NEW_CLK_DIV)
> +#define I2CCG_DIV_CTRL 0xC6411208
> +
> +/* 0x00 : I2CC Master/Slave Function Control Register  */
> +#define AST2600_I2CC_FUN_CTRL		0x00
> +#define AST2600_I2CC_SLAVE_ADDR_RX_EN		BIT(20)
> +#define AST2600_I2CC_MASTER_RETRY_MASK		GENMASK(19, 18)
> +#define AST2600_I2CC_MASTER_RETRY(x)		(((x) & GENMASK(1, 0)) <<
> 18)
> +#define AST2600_I2CC_BUS_AUTO_RELEASE		BIT(17)
> +#define AST2600_I2CC_M_SDA_LOCK_EN			BIT(16)
> +#define AST2600_I2CC_MULTI_MASTER_DIS		BIT(15)
> +#define AST2600_I2CC_M_SCL_DRIVE_EN			BIT(14)
> +#define AST2600_I2CC_MSB_STS				BIT(9)
> +#define AST2600_I2CC_SDA_DRIVE_1T_EN		BIT(8)
> +#define AST2600_I2CC_M_SDA_DRIVE_1T_EN		BIT(7)
> +#define AST2600_I2CC_M_HIGH_SPEED_EN		BIT(6)
> +/* reserver 5 : 2 */
> +#define AST2600_I2CC_SLAVE_EN			BIT(1)
> +#define AST2600_I2CC_MASTER_EN			BIT(0)
> +
> +/* 0x04 : I2CC Master/Slave Clock and AC Timing Control Register #1 */
> +#define AST2600_I2CC_AC_TIMING		0x04
> +#define AST2600_I2CC_TTIMEOUT(x)			(((x) & GENMASK(4,
0)) <<
> 24)
> +#define AST2600_I2CC_TCKHIGHMIN(x)			(((x) & GENMASK(3,
0))
> << 20)
> +#define AST2600_I2CC_TCKHIGH(x)			(((x) & GENMASK(3,
0)) <<
> 16)
> +#define AST2600_I2CC_TCKLOW(x)			(((x) & GENMASK(3,
0)) <<
> 12)
> +#define AST2600_I2CC_THDDAT(x)			(((x) & GENMASK(1,
0)) <<
> 10)
> +#define AST2600_I2CC_TOUTBASECLK(x)			(((x) & GENMASK(1,
0))
> << 8)
> +#define AST2600_I2CC_TBASECLK(x)			((x) & GENMASK(3,
0))
> +
> +/* 0x08 : I2CC Master/Slave Transmit/Receive Byte Buffer Register */
> +#define AST2600_I2CC_STS_AND_BUFF		0x08
> +#define AST2600_I2CC_TX_DIR_MASK			GENMASK(31, 29)
> +#define AST2600_I2CC_SDA_OE				BIT(28)
> +#define AST2600_I2CC_SDA_O				BIT(27)
> +#define AST2600_I2CC_SCL_OE				BIT(26)
> +#define AST2600_I2CC_SCL_O				BIT(25)
> +
> +#define AST2600_I2CC_SCL_LINE_STS			BIT(18)
> +#define AST2600_I2CC_SDA_LINE_STS			BIT(17)
> +#define AST2600_I2CC_BUS_BUSY_STS			BIT(16)
> +
> +#define AST2600_I2CC_GET_RX_BUFF(x)			(((x) >> 8) &
> GENMASK(7, 0))
> +
> +/* 0x0C : I2CC Master/Slave Pool Buffer Control Register  */
> +#define AST2600_I2CC_BUFF_CTRL		0x0C
> +#define AST2600_I2CC_GET_RX_BUF_LEN(x)		(((x) >> 24) &
> GENMASK(5, 0))
> +#define AST2600_I2CC_SET_RX_BUF_LEN(x)		(((((x) - 1) &
GENMASK(4,
> 0)) << 16) | BIT(0))
> +#define AST2600_I2CC_SET_TX_BUF_LEN(x)		(((((x) - 1) &
GENMASK(4,
> 0)) << 8) | BIT(0))
> +#define AST2600_I2CC_GET_TX_BUF_LEN(x)		((((x) >> 8) &
> GENMASK(4, 0)) + 1)
> +
> +/* 0x10 : I2CM Master Interrupt Control Register */
> +#define AST2600_I2CM_IER			0x10
> +/* 0x14 : I2CM Master Interrupt Status Register   : WC */
> +#define AST2600_I2CM_ISR			0x14
> +
> +#define AST2600_I2CM_PKT_TIMEOUT			BIT(18)
> +#define AST2600_I2CM_PKT_ERROR			BIT(17)
> +#define AST2600_I2CM_PKT_DONE			BIT(16)
> +
> +#define AST2600_I2CM_BUS_RECOVER_FAIL		BIT(15)
> +#define AST2600_I2CM_SDA_DL_TO			BIT(14)
> +#define AST2600_I2CM_BUS_RECOVER			BIT(13)
> +#define AST2600_I2CM_SMBUS_ALT			BIT(12)
> +
> +#define AST2600_I2CM_SCL_LOW_TO			BIT(6)
> +#define AST2600_I2CM_ABNORMAL			BIT(5)
> +#define AST2600_I2CM_NORMAL_STOP			BIT(4)
> +#define AST2600_I2CM_ARBIT_LOSS			BIT(3)
> +#define AST2600_I2CM_RX_DONE			BIT(2)
> +#define AST2600_I2CM_TX_NAK				BIT(1)
> +#define AST2600_I2CM_TX_ACK				BIT(0)
> +
> +/* 0x18 : I2CM Master Command/Status Register   */
> +#define AST2600_I2CM_CMD_STS		0x18
> +#define AST2600_I2CM_PKT_ADDR(x)			(((x) & GENMASK(6,
0))
> << 24)
> +#define AST2600_I2CM_PKT_EN				BIT(16)
> +#define AST2600_I2CM_SDA_OE_OUT_DIR			BIT(15)
> +#define AST2600_I2CM_SDA_O_OUT_DIR			BIT(14)
> +#define AST2600_I2CM_SCL_OE_OUT_DIR			BIT(13)
> +#define AST2600_I2CM_SCL_O_OUT_DIR			BIT(12)
> +#define AST2600_I2CM_RECOVER_CMD_EN			BIT(11)
> +
> +#define AST2600_I2CM_RX_DMA_EN			BIT(9)
> +#define AST2600_I2CM_TX_DMA_EN			BIT(8)
> +/* Command Bit */
> +#define AST2600_I2CM_RX_BUFF_EN			BIT(7)
> +#define AST2600_I2CM_TX_BUFF_EN			BIT(6)
> +#define AST2600_I2CM_STOP_CMD			BIT(5)
> +#define AST2600_I2CM_RX_CMD_LAST			BIT(4)
> +#define AST2600_I2CM_RX_CMD				BIT(3)
> +
> +#define AST2600_I2CM_TX_CMD				BIT(1)
> +#define AST2600_I2CM_START_CMD			BIT(0)
> +
> +/* 0x1C : I2CM Master DMA Transfer Length Register	 */
> +#define AST2600_I2CM_DMA_LEN		0x1C
> +/* Tx Rx support length 1 ~ 4096 */
> +#define AST2600_I2CM_SET_RX_DMA_LEN(x)	((((x) & GENMASK(11, 0)) <<
> 16) | BIT(31))
> +#define AST2600_I2CM_SET_TX_DMA_LEN(x)	(((x) & GENMASK(11, 0)) |
> BIT(15))
> +
> +/* 0x20 : I2CS Slave Interrupt Control Register   */
> +#define AST2600_I2CS_IER			0x20
> +/* 0x24 : I2CS Slave Interrupt Status Register	 */
> +#define AST2600_I2CS_ISR			0x24
> +
> +#define AST2600_I2CS_ADDR_INDICATE_MASK	GENMASK(31, 30)
> +#define AST2600_I2CS_SLAVE_PENDING			BIT(29)
> +
> +#define AST2600_I2CS_WAIT_TX_DMA			BIT(25)
> +#define AST2600_I2CS_WAIT_RX_DMA			BIT(24)
> +
> +#define AST2600_I2CS_ADDR3_NAK			BIT(22)
> +#define AST2600_I2CS_ADDR2_NAK			BIT(21)
> +#define AST2600_I2CS_ADDR1_NAK			BIT(20)
> +
> +#define AST2600_I2CS_ADDR_MASK			GENMASK(19, 18)
> +#define AST2600_I2CS_PKT_ERROR			BIT(17)
> +#define AST2600_I2CS_PKT_DONE			BIT(16)
> +#define AST2600_I2CS_INACTIVE_TO			BIT(15)
> +
> +#define AST2600_I2CS_SLAVE_MATCH			BIT(7)
> +#define AST2600_I2CS_ABNOR_STOP			BIT(5)
> +#define AST2600_I2CS_STOP				BIT(4)
> +#define AST2600_I2CS_RX_DONE_NAK			BIT(3)
> +#define AST2600_I2CS_RX_DONE			BIT(2)
> +#define AST2600_I2CS_TX_NAK				BIT(1)
> +#define AST2600_I2CS_TX_ACK				BIT(0)
> +
> +/* 0x28 : I2CS Slave CMD/Status Register   */
> +#define AST2600_I2CS_CMD_STS		0x28
> +#define AST2600_I2CS_ACTIVE_ALL			GENMASK(18, 17)
> +#define AST2600_I2CS_PKT_MODE_EN			BIT(16)
> +#define AST2600_I2CS_AUTO_NAK_NOADDR		BIT(15)
> +#define AST2600_I2CS_AUTO_NAK_EN			BIT(14)
> +
> +#define AST2600_I2CS_ALT_EN				BIT(10)
> +#define AST2600_I2CS_RX_DMA_EN			BIT(9)
> +#define AST2600_I2CS_TX_DMA_EN			BIT(8)
> +#define AST2600_I2CS_RX_BUFF_EN			BIT(7)
> +#define AST2600_I2CS_TX_BUFF_EN			BIT(6)
> +#define AST2600_I2CS_RX_CMD_LAST			BIT(4)
> +
> +#define AST2600_I2CS_TX_CMD				BIT(2)
> +
> +#define AST2600_I2CS_DMA_LEN		0x2C
> +#define AST2600_I2CS_SET_RX_DMA_LEN(x)	(((((x) - 1) & GENMASK(11,
0))
> << 16) | BIT(31))
> +#define AST2600_I2CS_RX_DMA_LEN_MASK	(GENMASK(11, 0) << 16)
> +
> +#define AST2600_I2CS_SET_TX_DMA_LEN(x)	((((x) - 1) & GENMASK(11,
0))
> | BIT(15))
> +#define AST2600_I2CS_TX_DMA_LEN_MASK	GENMASK(11, 0)
> +
> +/* I2CM Master DMA Tx Buffer Register   */
> +#define AST2600_I2CM_TX_DMA			0x30
> +/* I2CM Master DMA Rx Buffer Register	*/
> +#define AST2600_I2CM_RX_DMA			0x34
> +/* I2CS Slave DMA Tx Buffer Register   */
> +#define AST2600_I2CS_TX_DMA			0x38
> +/* I2CS Slave DMA Rx Buffer Register   */
> +#define AST2600_I2CS_RX_DMA			0x3C
> +
> +#define AST2600_I2CS_ADDR_CTRL		0x40
> +
> +#define	AST2600_I2CS_ADDR3_MASK		GENMASK(22, 16)
> +#define	AST2600_I2CS_ADDR2_MASK		GENMASK(14, 8)
> +#define	AST2600_I2CS_ADDR1_MASK		GENMASK(6, 0)
> +
> +#define AST2600_I2CM_DMA_LEN_STS		0x48
> +#define AST2600_I2CS_DMA_LEN_STS		0x4C
> +
> +#define AST2600_I2C_GET_TX_DMA_LEN(x)		((x) & GENMASK(12,
0))
> +#define AST2600_I2C_GET_RX_DMA_LEN(x)		(((x) >> 16) &
> GENMASK(12, 0))
> +
> +/* 0x40 : Slave Device Address Register */
> +#define AST2600_I2CS_ADDR3_ENABLE			BIT(23)
> +#define AST2600_I2CS_ADDR3(x)			((x) << 16)
> +#define AST2600_I2CS_ADDR2_ENABLE			BIT(15)
> +#define AST2600_I2CS_ADDR2(x)			((x) << 8)
> +#define AST2600_I2CS_ADDR1_ENABLE			BIT(7)
> +#define AST2600_I2CS_ADDR1(x)			(x)
> +
> +#define I2C_SLAVE_MSG_BUF_SIZE		256
> +
> +#define AST2600_I2C_DMA_SIZE		4096
> +
> +#define MASTER_TRIGGER_LAST_STOP	(AST2600_I2CM_RX_CMD_LAST |
> AST2600_I2CM_STOP_CMD)
> +#define SLAVE_TRIGGER_CMD	(AST2600_I2CS_ACTIVE_ALL |
> AST2600_I2CS_PKT_MODE_EN)
> +
> +#define AST_I2C_TIMEOUT_CLK		0x2
> +
> +struct ast2600_i2c_timing_table {
> +	u32 divisor;
> +	u32 timing;
> +};
> +
> +enum xfer_mode {
> +	BYTE_MODE = 0,
> +	BUFF_MODE,
> +	DMA_MODE,
> +};
> +
> +struct ast2600_i2c_bus {
> +	struct i2c_adapter		adap;
> +	struct device			*dev;
> +	void __iomem			*reg_base;
> +	struct regmap			*global_regs;
> +	struct reset_control		*rst;
> +	int				irq;
> +	enum xfer_mode			mode;
> +	struct clk			*clk;
> +	u32				apb_clk;
> +	u32				bus_frequency;
> +	int				slave_operate;
> +	u32				timeout;
> +	/* smbus alert */
> +	int				alert_enable;
> +	struct i2c_smbus_alert_setup	alert_data;
> +	struct i2c_client		*ara;
> +	/* Multi-master */
> +	bool				multi_master;
> +	/* master structure */
> +	int				cmd_err;
> +	struct completion		cmd_complete;
> +	struct i2c_msg			*msgs;
> +	size_t				buf_index;
> +	/* cur xfer msgs index*/
> +	int				msgs_index;
> +	int				msgs_count;
> +	u8				*master_safe_buf;
> +	dma_addr_t			master_dma_addr;
> +	/*total xfer count */
> +	int				master_xfer_cnt;
> +	/* Buffer mode */
> +	void __iomem			*buf_base;
> +	size_t				buf_size;
> +	/* Slave structure */
> +	int				slave_xfer_len;
> +	int				slave_xfer_cnt;
> +#ifdef CONFIG_I2C_SLAVE
> +	unsigned char			*slave_dma_buf;
> +	dma_addr_t			slave_dma_addr;
> +	struct i2c_client		*slave;
> +#endif
> +};
> +
> +static u32 ast2600_select_i2c_clock(struct ast2600_i2c_bus *i2c_bus)
> +{
> +	unsigned long base_clk1;
> +	unsigned long base_clk2;
> +	unsigned long base_clk3;
> +	unsigned long base_clk4;
> +	int baseclk_idx;
> +	u32 clk_div_reg;
> +	u32 scl_low;
> +	u32 scl_high;
> +	int divisor;
> +	int inc = 0;
> +	u32 data;
> +
> +	regmap_read(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL,
> &clk_div_reg);
> +	base_clk1 = (i2c_bus->apb_clk * 10) / ((((clk_div_reg & 0xff) + 2) *
10) /
> 2);
> +	base_clk2 = (i2c_bus->apb_clk * 10) /
> +			(((((clk_div_reg >> 8) & 0xff) + 2) * 10) / 2);
> +	base_clk3 = (i2c_bus->apb_clk * 10) /
> +			(((((clk_div_reg >> 16) & 0xff) + 2) * 10) / 2);
> +	base_clk4 = (i2c_bus->apb_clk * 10) /
> +			(((((clk_div_reg >> 24) & 0xff) + 2) * 10) / 2);
> +
> +	if ((i2c_bus->apb_clk / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 0;
> +		divisor = DIV_ROUND_UP(i2c_bus->apb_clk,
> i2c_bus->bus_frequency);
> +	} else if ((base_clk1 / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 1;
> +		divisor = DIV_ROUND_UP(base_clk1, i2c_bus->bus_frequency);
> +	} else if ((base_clk2 / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 2;
> +		divisor = DIV_ROUND_UP(base_clk2, i2c_bus->bus_frequency);
> +	} else if ((base_clk3 / i2c_bus->bus_frequency) <= 32) {
> +		baseclk_idx = 3;
> +		divisor = DIV_ROUND_UP(base_clk3, i2c_bus->bus_frequency);
> +	} else {
> +		baseclk_idx = 4;
> +		divisor = DIV_ROUND_UP(base_clk4, i2c_bus->bus_frequency);
> +		inc = 0;
> +		while ((divisor + inc) > 32) {
> +			inc |= divisor & 0x1;
> +			divisor >>= 1;
> +			baseclk_idx++;
> +		}
> +		divisor += inc;
> +	}
> +	divisor = min_t(int, divisor, 32);
> +	baseclk_idx &= 0xf;
> +	scl_low = ((divisor * 9) / 16) - 1;
> +	scl_low = min_t(u32, scl_low, 0xf);
> +	scl_high = (divisor - scl_low - 2) & 0xf;
> +	/* Divisor : Base Clock : tCKHighMin : tCK High : tCK Low  */
> +	data = ((scl_high - 1) << 20) | (scl_high << 16) | (scl_low << 12) |
> (baseclk_idx);
> +	if (i2c_bus->timeout) {
> +		data |= AST2600_I2CC_TOUTBASECLK(AST_I2C_TIMEOUT_CLK);
> +		data |= AST2600_I2CC_TTIMEOUT(i2c_bus->timeout);
> +	}
> +
> +	return data;
> +}
> +
> +static u8 ast2600_i2c_recover_bus(struct ast2600_i2c_bus *i2c_bus)
> +{
> +	int ret = 0;
> +	u32 ctrl;
> +	u32 state;
> +	int r;
> +
> +	dev_dbg(i2c_bus->dev, "%d-bus recovery bus [%x]\n",
i2c_bus->adap.nr,
> +		readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> +
> +	ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> +	writel(ctrl & ~(AST2600_I2CC_MASTER_EN | AST2600_I2CC_SLAVE_EN),
> +	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> +	writel(readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) |
> AST2600_I2CC_MASTER_EN,
> +	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> +	reinit_completion(&i2c_bus->cmd_complete);
> +	i2c_bus->cmd_err = 0;
> +
> +	/* Check 0x14's SDA and SCL status */
> +	state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
> +	if (!(state & AST2600_I2CC_SDA_LINE_STS) && (state &
> AST2600_I2CC_SCL_LINE_STS)) {
> +		writel(AST2600_I2CM_RECOVER_CMD_EN, i2c_bus->reg_base +
> AST2600_I2CM_CMD_STS);
> +		r = wait_for_completion_timeout(&i2c_bus->cmd_complete,
> i2c_bus->adap.timeout);
> +		if (r == 0) {
> +			dev_dbg(i2c_bus->dev, "recovery timed out\n");
> +			ret = -ETIMEDOUT;
> +		} else {
> +			if (i2c_bus->cmd_err) {
> +				dev_dbg(i2c_bus->dev, "recovery error\n");
> +				ret = -EPROTO;
> +			}
> +		}
> +	}
> +
> +	dev_dbg(i2c_bus->dev, "Recovery done [%x]\n",
> +		readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
> +	if (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
> AST2600_I2CC_BUS_BUSY_STS) {
> +		dev_dbg(i2c_bus->dev, "Can't recovery bus [%x]\n",
> +			readl(i2c_bus->reg_base +
AST2600_I2CC_STS_AND_BUFF));
> +		ret = -EPROTO;
> +	}
> +
> +	writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +	return ret;
> +}
> +
> +#ifdef CONFIG_I2C_SLAVE
> +static void ast2600_i2c_slave_packet_dma_irq(struct ast2600_i2c_bus
> *i2c_bus, u32 sts)
> +{
> +	int slave_rx_len;
> +	u32 cmd = 0;
> +	u8 value;
> +	int i = 0;
> +
> +	sts &= ~(AST2600_I2CS_SLAVE_PENDING);
> +	/* Handle i2c slave timeout condition */
> +	if (AST2600_I2CS_INACTIVE_TO & sts) {
> +		cmd = SLAVE_TRIGGER_CMD;
> +		cmd |= AST2600_I2CS_RX_DMA_EN;
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_ISR);
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		return;
> +	}
> +
> +	sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
> +
> +	switch (sts) {
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_WAIT_RX_DMA:
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +		slave_rx_len =
> AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CS_DMA_LEN_STS));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> +					&i2c_bus->slave_dma_buf[i]);
> +		}
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +				i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> +		break;
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +				i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> +		break;
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE_NAK |
> +			AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA |
> +			AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> +	case AST2600_I2CS_RX_DONE_NAK | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_STOP:
> +	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA |
> AST2600_I2CS_STOP:
> +	case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> +	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_STOP:
> +		if (sts & AST2600_I2CS_SLAVE_MATCH)
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +
> +		slave_rx_len =
> AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CS_DMA_LEN_STS));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> +					&i2c_bus->slave_dma_buf[i]);
> +		}
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		if (sts & AST2600_I2CS_STOP)
> +			i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP,
&value);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> +		break;
> +
> +	/* it is Mw data Mr coming -> it need send tx */
> +	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_WAIT_TX_DMA:
> +		/* it should be repeat start read */
> +		if (sts & AST2600_I2CS_SLAVE_MATCH)
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +
> +		slave_rx_len =
> AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CS_DMA_LEN_STS));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> +					&i2c_bus->slave_dma_buf[i]);
> +		}
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
> +				&i2c_bus->slave_dma_buf[0]);
> +		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
> +		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
> +				i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
> +		break;
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_TX_DMA:
> +		/* First Start read */
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
> +				&i2c_bus->slave_dma_buf[0]);
> +		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
> +				i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
> +		break;
> +	case AST2600_I2CS_WAIT_TX_DMA:
> +		/* it should be next start read */
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED,
> +				&i2c_bus->slave_dma_buf[0]);
> +		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
> +		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
> +				i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
> +		break;
> +
> +	case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
> +		/* it just tx complete */
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
> +		break;
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
> +		cmd = 0;
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +		break;
> +	case AST2600_I2CS_STOP:
> +		cmd = 0;
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		break;
> +	default:
> +		dev_dbg(i2c_bus->dev, "unhandled slave isr case %x, sts
%x\n", sts,
> +			readl(i2c_bus->reg_base +
AST2600_I2CC_STS_AND_BUFF));
> +		break;
> +	}
> +
> +	if (cmd)
> +		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +	writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_ISR);
> +	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +}
> +
> +static void ast2600_i2c_slave_packet_buff_irq(struct ast2600_i2c_bus
> *i2c_bus, u32 sts)
> +{
> +	int slave_rx_len = 0;
> +	u32 cmd = 0;
> +	u8 value;
> +	int i = 0;
> +
> +	/* due to master slave is common buffer, so need force the master
stop
> not issue */
> +	if (readl(i2c_bus->reg_base + AST2600_I2CM_CMD_STS) & 0xffff) {
> +		writel(0, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
> +		i2c_bus->cmd_err = -EBUSY;
> +		writel(0, i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		complete(&i2c_bus->cmd_complete);
> +	}
> +
> +	/* Handle i2c slave timeout condition */
> +	if (AST2600_I2CS_INACTIVE_TO & sts) {
> +		writel(SLAVE_TRIGGER_CMD, i2c_bus->reg_base +
> AST2600_I2CS_CMD_STS);
> +		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_ISR);
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		i2c_bus->slave_operate = 0;
> +		return;
> +	}
> +
> +	sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
> +
> +	if (sts & AST2600_I2CS_SLAVE_MATCH)
> +		i2c_bus->slave_operate = 1;
> +
> +	switch (sts) {
> +	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
> +		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_STOP:
> +	case AST2600_I2CS_SLAVE_PENDING |
> +		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_STOP:
> +	case AST2600_I2CS_SLAVE_PENDING |
> +		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		fallthrough;
> +	case AST2600_I2CS_SLAVE_PENDING |
> +		 AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH |
> AST2600_I2CS_RX_DONE:
> +	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH |
> AST2600_I2CS_RX_DONE:
> +	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +		cmd = SLAVE_TRIGGER_CMD;
> +		if (sts & AST2600_I2CS_RX_DONE) {
> +			slave_rx_len =
> AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +			for (i = 0; i < slave_rx_len; i++) {
> +				value = readb(i2c_bus->buf_base + 0x10 + i);
> +				i2c_slave_event(i2c_bus->slave,
> I2C_SLAVE_WRITE_RECEIVED, &value);
> +			}
> +		}
> +		if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) &
> AST2600_I2CS_RX_BUFF_EN)
> +			cmd = 0;
> +		else
> +			cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
> +
> +		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
> +					i2c_bus->reg_base +
AST2600_I2CC_BUFF_CTRL);
> +		break;
> +	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_RX_DONE:
> +		cmd = SLAVE_TRIGGER_CMD;
> +		slave_rx_len =
> AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			value = readb(i2c_bus->buf_base + 0x10 + i);
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> &value);
> +		}
> +		cmd |= AST2600_I2CS_RX_BUFF_EN;
> +		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
> +						i2c_bus->reg_base +
> AST2600_I2CC_BUFF_CTRL);
> +		break;
> +	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
> +				AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> +		cmd = SLAVE_TRIGGER_CMD;
> +		slave_rx_len =
> AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			value = readb(i2c_bus->buf_base + 0x10 + i);
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> &value);
> +		}
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		cmd |= AST2600_I2CS_RX_BUFF_EN;
> +		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
> +						i2c_bus->reg_base +
> AST2600_I2CC_BUFF_CTRL);
> +		break;
> +
> +	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_STOP:
> +		cmd = SLAVE_TRIGGER_CMD;
> +		slave_rx_len =
> AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			value = readb(i2c_bus->buf_base + 0x10 + i);
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> &value);
> +		}
> +		/* workaround for avoid next start with len != 0 */
> +		writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		break;
> +
> +	case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
> +		cmd = SLAVE_TRIGGER_CMD;
> +		slave_rx_len =
> AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +		for (i = 0; i < slave_rx_len; i++) {
> +			value = readb(i2c_bus->buf_base + 0x10 + i);
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_WRITE_RECEIVED,
> &value);
> +		}
> +		/* workaround for avoid next start with len != 0 */
> +		writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		break;
> +	case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_SLAVE_MATCH:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
> &value);
> +		writeb(value, i2c_bus->buf_base);
> +		writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
> +				i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
> +		break;
> +	case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_RX_DONE:
> +	case AST2600_I2CS_WAIT_TX_DMA:
> +		if (sts & AST2600_I2CS_RX_DONE) {
> +			slave_rx_len =
> AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +			for (i = 0; i < slave_rx_len; i++) {
> +				value = readb(i2c_bus->buf_base + 0x10 + i);
> +				i2c_slave_event(i2c_bus->slave,
> I2C_SLAVE_WRITE_RECEIVED, &value);
> +			}
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_READ_REQUESTED,
> &value);
> +		} else {
> +			i2c_slave_event(i2c_bus->slave,
I2C_SLAVE_READ_PROCESSED,
> &value);
> +		}
> +		writeb(value, i2c_bus->buf_base);
> +		writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
> +				i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
> +		break;
> +	/* workaround : trigger the cmd twice to fix next state keep 1000000
*/
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +		cmd = SLAVE_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
> +		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +		break;
> +
> +	case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
> +	case AST2600_I2CS_STOP:
> +		cmd = SLAVE_TRIGGER_CMD;
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		break;
> +	default:
> +		dev_dbg(i2c_bus->dev, "unhandled slave isr case %x, sts
%x\n", sts,
> +			readl(i2c_bus->reg_base +
AST2600_I2CC_STS_AND_BUFF));
> +		break;
> +	}
> +
> +	if (cmd)
> +		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +	writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_ISR);
> +	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +
> +	if ((sts & AST2600_I2CS_STOP) && !(sts &
> AST2600_I2CS_SLAVE_PENDING))
> +		i2c_bus->slave_operate = 0;
> +
> +}
> +
> +static void ast2600_i2c_slave_byte_irq(struct ast2600_i2c_bus *i2c_bus,
u32
> sts)
> +{
> +	u32 i2c_buff = readl(i2c_bus->reg_base +
> AST2600_I2CC_STS_AND_BUFF);
> +	u32 cmd = AST2600_I2CS_ACTIVE_ALL;
> +	u8 byte_data;
> +	u8 value;
> +
> +	switch (sts) {
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_WAIT_RX_DMA:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_REQUESTED,
> &value);
> +		/* first address match is address */
> +		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
> +		break;
> +	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
> +		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_WRITE_RECEIVED,
> &byte_data);
> +		break;
> +	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE |
> AST2600_I2CS_WAIT_TX_DMA:
> +		cmd |= AST2600_I2CS_TX_CMD;
> +		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_REQUESTED,
> &byte_data);
> +		writel(byte_data, i2c_bus->reg_base +
> AST2600_I2CC_STS_AND_BUFF);
> +		break;
> +	case AST2600_I2CS_TX_ACK | AST2600_I2CS_WAIT_TX_DMA:
> +		cmd |= AST2600_I2CS_TX_CMD;
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_READ_PROCESSED,
> &byte_data);
> +		writel(byte_data, i2c_bus->reg_base +
> AST2600_I2CC_STS_AND_BUFF);
> +		break;
> +	case AST2600_I2CS_STOP:
> +	case AST2600_I2CS_STOP | AST2600_I2CS_TX_NAK:
> +		i2c_slave_event(i2c_bus->slave, I2C_SLAVE_STOP, &value);
> +		break;
> +	default:
> +		dev_dbg(i2c_bus->dev, "unhandled pkt isr %x\n", sts);
> +		break;
> +	}
> +	writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +	writel(sts, i2c_bus->reg_base + AST2600_I2CS_ISR);
> +	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +}
> +
> +static int ast2600_i2c_slave_irq(struct ast2600_i2c_bus *i2c_bus)
> +{
> +	u32 ier = readl(i2c_bus->reg_base + AST2600_I2CS_IER);
> +	u32 isr = readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
> +
> +	if (!(isr & ier))
> +		return 0;
> +
> +	/* Slave interrupt coming after Master package done
> +	 * So need handle master first.
> +	 */
> +	if (readl(i2c_bus->reg_base + AST2600_I2CM_ISR) &
> AST2600_I2CM_PKT_DONE)
> +		return 0;
> +
> +	isr &= ~(AST2600_I2CS_ADDR_INDICATE_MASK);
> +
> +	if (AST2600_I2CS_ADDR1_NAK & isr)
> +		isr &= ~AST2600_I2CS_ADDR1_NAK;
> +
> +	if (AST2600_I2CS_ADDR2_NAK & isr)
> +		isr &= ~AST2600_I2CS_ADDR2_NAK;
> +
> +	if (AST2600_I2CS_ADDR3_NAK & isr)
> +		isr &= ~AST2600_I2CS_ADDR3_NAK;
> +
> +	if (AST2600_I2CS_ADDR_MASK & isr)
> +		isr &= ~AST2600_I2CS_ADDR_MASK;
> +
> +	if (AST2600_I2CS_PKT_DONE & isr) {
> +		if (i2c_bus->mode == DMA_MODE)
> +			ast2600_i2c_slave_packet_dma_irq(i2c_bus, isr);
> +		else
> +			ast2600_i2c_slave_packet_buff_irq(i2c_bus, isr);
> +	} else
> +		ast2600_i2c_slave_byte_irq(i2c_bus, isr);
> +
> +	return 1;
> +}
> +#endif
> +
> +static int ast2600_i2c_do_start(struct ast2600_i2c_bus *i2c_bus)
> +{
> +	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
> +	int xfer_len = 0;
> +	int i = 0;
> +	u32 cmd;
> +
> +	cmd = AST2600_I2CM_PKT_EN | AST2600_I2CM_PKT_ADDR(msg->addr)
> | AST2600_I2CM_START_CMD;
> +
> +	/* send start */
> +	dev_dbg(i2c_bus->dev, "[%d] %sing %d byte%s %s 0x%02x\n",
> +		i2c_bus->msgs_index, msg->flags & I2C_M_RD ? "read" :
"write",
> +		msg->len, msg->len > 1 ? "s" : "",
> +		msg->flags & I2C_M_RD ? "from" : "to", msg->addr);
> +
> +	i2c_bus->master_xfer_cnt = 0;
> +	i2c_bus->buf_index = 0;
> +
> +	if (msg->flags & I2C_M_RD) {
> +		cmd |= AST2600_I2CM_RX_CMD;
> +		if (i2c_bus->mode == DMA_MODE) {
> +			/* dma mode */
> +			cmd |= AST2600_I2CM_RX_DMA_EN;
> +
> +			if (msg->flags & I2C_M_RECV_LEN) {
> +				xfer_len = 1;
> +			} else {
> +				if (msg->len > AST2600_I2C_DMA_SIZE) {
> +					xfer_len = AST2600_I2C_DMA_SIZE;
> +				} else {
> +					xfer_len = msg->len;
> +					if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +						cmd |=
MASTER_TRIGGER_LAST_STOP;
> +				}
> +			}
> +			writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1),
> +			       i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
> +			i2c_bus->master_safe_buf =
i2c_get_dma_safe_msg_buf(msg,
> 1);
> +			if (!i2c_bus->master_safe_buf)
> +				return -ENOMEM;
> +			i2c_bus->master_dma_addr =
> +				dma_map_single(i2c_bus->dev,
i2c_bus->master_safe_buf,
> +								msg->len,
DMA_FROM_DEVICE);
> +			if (dma_mapping_error(i2c_bus->dev,
> i2c_bus->master_dma_addr)) {
> +
i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf,
> msg, false);
> +				i2c_bus->master_safe_buf = NULL;
> +				return -ENOMEM;
> +			}
> +			writel(i2c_bus->master_dma_addr, i2c_bus->reg_base +
> AST2600_I2CM_RX_DMA);
> +		} else if (i2c_bus->mode == BUFF_MODE) {
> +			/* buff mode */
> +			cmd |= AST2600_I2CM_RX_BUFF_EN;
> +			if (msg->flags & I2C_M_RECV_LEN) {
> +				dev_dbg(i2c_bus->dev, "smbus read\n");
> +				xfer_len = 1;
> +			} else {
> +				if (msg->len > i2c_bus->buf_size) {
> +					xfer_len = i2c_bus->buf_size;
> +				} else {
> +					xfer_len = msg->len;
> +					if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +						cmd |=
MASTER_TRIGGER_LAST_STOP;
> +				}
> +			}
> +			writel(AST2600_I2CC_SET_RX_BUF_LEN(xfer_len),
> +			       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
> +		} else {
> +			/* byte mode */
> +			xfer_len = 1;
> +			if (msg->flags & I2C_M_RECV_LEN) {
> +				dev_dbg(i2c_bus->dev, "smbus read\n");
> +			} else {
> +				if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count) {
> +					if (msg->len == 1)
> +						cmd |=
MASTER_TRIGGER_LAST_STOP;
> +				}
> +			}
> +		}
> +	} else {
> +		if (i2c_bus->mode == DMA_MODE) {
> +			/* dma mode */
> +			if (msg->len > AST2600_I2C_DMA_SIZE) {
> +				xfer_len = AST2600_I2C_DMA_SIZE;
> +			} else {
> +				if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +					cmd |= AST2600_I2CM_STOP_CMD;
> +				xfer_len = msg->len;
> +			}
> +
> +			if (xfer_len) {
> +				cmd |= AST2600_I2CM_TX_DMA_EN |
> AST2600_I2CM_TX_CMD;
> +				writel(AST2600_I2CM_SET_TX_DMA_LEN(xfer_len
- 1),
> +				       i2c_bus->reg_base +
AST2600_I2CM_DMA_LEN);
> +				i2c_bus->master_safe_buf =
> i2c_get_dma_safe_msg_buf(msg, 1);
> +				if (!i2c_bus->master_safe_buf)
> +					return -ENOMEM;
> +				i2c_bus->master_dma_addr =
> +					dma_map_single(i2c_bus->dev,
> i2c_bus->master_safe_buf,
> +								msg->len,
DMA_TO_DEVICE);
> +				if (dma_mapping_error(i2c_bus->dev,
> i2c_bus->master_dma_addr)) {
> +
> 	i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf,
> +
msg, false);
> +					i2c_bus->master_safe_buf = NULL;
> +					return -ENOMEM;
> +				}
> +				writel(i2c_bus->master_dma_addr,
> +				       i2c_bus->reg_base +
AST2600_I2CM_TX_DMA);
> +			}
> +		} else if (i2c_bus->mode == BUFF_MODE) {
> +			u8 wbuf[4];
> +			/* buff mode */
> +			if (msg->len > i2c_bus->buf_size) {
> +				xfer_len = i2c_bus->buf_size;
> +			} else {
> +				if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +					cmd |= AST2600_I2CM_STOP_CMD;
> +				xfer_len = msg->len;
> +			}
> +			if (xfer_len) {
> +				cmd |= AST2600_I2CM_TX_BUFF_EN |
> AST2600_I2CM_TX_CMD;
> +				if (readl(i2c_bus->reg_base +
AST2600_I2CS_ISR))
> +					return -ENOMEM;
> +
writel(AST2600_I2CC_SET_TX_BUF_LEN(xfer_len),
> +				       i2c_bus->reg_base +
AST2600_I2CC_BUFF_CTRL);
> +				if (readl(i2c_bus->reg_base +
AST2600_I2CS_ISR))
> +					return -ENOMEM;
> +				for (i = 0; i < xfer_len; i++) {
> +					wbuf[i % 4] = msg->buf[i];
> +					if (i % 4 == 3)
> +						writel(*(u32 *)wbuf,
i2c_bus->buf_base + i - 3);
> +				}
> +				if (--i % 4 != 3)
> +					writel(*(u32 *)wbuf,
i2c_bus->buf_base + i - (i % 4));
> +			}
> +			if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR))
> +				return -ENOMEM;
> +		} else {
> +			/* byte mode */
> +			if ((i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
&&
> (msg->len <= 1))
> +				cmd |= AST2600_I2CM_STOP_CMD;
> +
> +			if (msg->len) {
> +				cmd |= AST2600_I2CM_TX_CMD;
> +				xfer_len = 1;
> +				writel(msg->buf[0], i2c_bus->reg_base +
> AST2600_I2CC_STS_AND_BUFF);
> +			} else {
> +				xfer_len = 0;
> +			}
> +		}
> +	}
> +	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
> +	return 0;
> +}
> +
> +static int ast2600_i2c_is_irq_error(u32 irq_status)
> +{
> +	if (irq_status & AST2600_I2CM_ARBIT_LOSS)
> +		return -EAGAIN;
> +	if (irq_status & (AST2600_I2CM_SDA_DL_TO |
> AST2600_I2CM_SCL_LOW_TO))
> +		return -EBUSY;
> +	if (irq_status & (AST2600_I2CM_ABNORMAL))
> +		return -EPROTO;
> +
> +	return 0;
> +}
> +
> +static void ast2600_i2c_master_package_irq(struct ast2600_i2c_bus
*i2c_bus,
> u32 sts)
> +{
> +	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
> +	u32 cmd = AST2600_I2CM_PKT_EN;
> +	int xfer_len;
> +	int i;
> +
> +	sts &= ~AST2600_I2CM_PKT_DONE;
> +	writel(AST2600_I2CM_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CM_ISR);
> +	switch (sts) {
> +	case AST2600_I2CM_PKT_ERROR:
> +		i2c_bus->cmd_err = -EAGAIN;
> +		complete(&i2c_bus->cmd_complete);
> +		break;
> +	case AST2600_I2CM_PKT_ERROR | AST2600_I2CM_TX_NAK: /* a0 fix for
> issue */
> +		fallthrough;
> +	case AST2600_I2CM_PKT_ERROR | AST2600_I2CM_TX_NAK |
> AST2600_I2CM_NORMAL_STOP:
> +		i2c_bus->cmd_err = -ENXIO;
> +		complete(&i2c_bus->cmd_complete);
> +		break;
> +	case AST2600_I2CM_NORMAL_STOP:
> +		/* write 0 byte only have stop isr */
> +		i2c_bus->msgs_index++;
> +		if (i2c_bus->msgs_index < i2c_bus->msgs_count) {
> +			if (ast2600_i2c_do_start(i2c_bus)) {
> +				i2c_bus->cmd_err = -ENOMEM;
> +				complete(&i2c_bus->cmd_complete);
> +			}
> +		} else {
> +			i2c_bus->cmd_err = i2c_bus->msgs_index;
> +			complete(&i2c_bus->cmd_complete);
> +		}
> +		break;
> +	case AST2600_I2CM_TX_ACK:
> +	case AST2600_I2CM_TX_ACK | AST2600_I2CM_NORMAL_STOP:
> +		if (i2c_bus->mode == DMA_MODE)
> +			xfer_len =
> AST2600_I2C_GET_TX_DMA_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CM_DMA_LEN_STS));
> +		else if (i2c_bus->mode == BUFF_MODE)
> +			xfer_len =
> AST2600_I2CC_GET_TX_BUF_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_BUFF_CTRL));
> +		else
> +			xfer_len = 1;
> +
> +		i2c_bus->master_xfer_cnt += xfer_len;
> +
> +		if (i2c_bus->master_xfer_cnt == msg->len) {
> +			if (i2c_bus->mode == DMA_MODE) {
> +				dma_unmap_single(i2c_bus->dev,
> i2c_bus->master_dma_addr, msg->len,
> +						 DMA_TO_DEVICE);
> +
i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf,
> msg, true);
> +				i2c_bus->master_safe_buf = NULL;
> +			}
> +			i2c_bus->msgs_index++;
> +			if (i2c_bus->msgs_index == i2c_bus->msgs_count) {
> +				i2c_bus->cmd_err = i2c_bus->msgs_index;
> +				complete(&i2c_bus->cmd_complete);
> +			} else {
> +				if (ast2600_i2c_do_start(i2c_bus)) {
> +					i2c_bus->cmd_err = -ENOMEM;
> +					complete(&i2c_bus->cmd_complete);
> +				}
> +			}
> +		} else {
> +			/* do next tx */
> +			cmd |= AST2600_I2CM_TX_CMD;
> +			if (i2c_bus->mode == DMA_MODE) {
> +				cmd |= AST2600_I2CM_TX_DMA_EN;
> +				xfer_len = msg->len -
i2c_bus->master_xfer_cnt;
> +				if (xfer_len > AST2600_I2C_DMA_SIZE) {
> +					xfer_len = AST2600_I2C_DMA_SIZE;
> +				} else {
> +					if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +						cmd |=
AST2600_I2CM_STOP_CMD;
> +				}
> +				writel(AST2600_I2CM_SET_TX_DMA_LEN(xfer_len
- 1),
> +				       i2c_bus->reg_base +
AST2600_I2CM_DMA_LEN);
> +				writel(i2c_bus->master_dma_addr +
> i2c_bus->master_xfer_cnt,
> +				       i2c_bus->reg_base +
AST2600_I2CM_TX_DMA);
> +			} else if (i2c_bus->mode == BUFF_MODE) {
> +				u8 wbuf[4];
> +
> +				cmd |= AST2600_I2CM_TX_BUFF_EN;
> +				xfer_len = msg->len -
i2c_bus->master_xfer_cnt;
> +				if (xfer_len > i2c_bus->buf_size) {
> +					xfer_len = i2c_bus->buf_size;
> +				} else {
> +					if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +						cmd |=
AST2600_I2CM_STOP_CMD;
> +				}
> +				for (i = 0; i < xfer_len; i++) {
> +					wbuf[i % 4] =
msg->buf[i2c_bus->master_xfer_cnt + i];
> +					if (i % 4 == 3)
> +						writel(*(u32 *)wbuf,
i2c_bus->buf_base + i - 3);
> +				}
> +				if (--i % 4 != 3)
> +					writel(*(u32 *)wbuf,
i2c_bus->buf_base + i - (i % 4));
> +
writel(AST2600_I2CC_SET_TX_BUF_LEN(xfer_len),
> +				       i2c_bus->reg_base +
AST2600_I2CC_BUFF_CTRL);
> +			} else {
> +				/* byte */
> +				if ((i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count) &&
> +				    ((i2c_bus->master_xfer_cnt + 1) ==
msg->len)) {
> +					cmd |= AST2600_I2CM_STOP_CMD;
> +				}
> +				writel(msg->buf[i2c_bus->master_xfer_cnt],
> +				       i2c_bus->reg_base +
> AST2600_I2CC_STS_AND_BUFF);
> +			}
> +			writel(cmd, i2c_bus->reg_base +
AST2600_I2CM_CMD_STS);
> +		}
> +		break;
> +	case AST2600_I2CM_RX_DONE:
> +#ifdef CONFIG_I2C_SLAVE
> +		/* Workaround for master/slave package mode enable rx done
stuck
> issue
> +		 * When master go for first read (RX_DONE), slave mode will
also
> effect
> +		 * Then controller will send nack, not operate anymore.
> +		 */
> +		if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) &
> AST2600_I2CS_PKT_MODE_EN) {
> +			u32 slave_cmd = readl(i2c_bus->reg_base +
> AST2600_I2CS_CMD_STS);
> +
> +			writel(0, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +			writel(slave_cmd, i2c_bus->reg_base +
> AST2600_I2CS_CMD_STS);
> +		}
> +		fallthrough;
> +#endif
> +	case AST2600_I2CM_RX_DONE | AST2600_I2CM_NORMAL_STOP:
> +		/* do next rx */
> +		if (i2c_bus->mode == DMA_MODE) {
> +			xfer_len =
> AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
> +
AST2600_I2CM_DMA_LEN_STS));
> +		} else if (i2c_bus->mode == BUFF_MODE) {
> +			xfer_len = AST2600_I2CC_GET_RX_BUF_LEN(
> +						readl(i2c_bus->reg_base +
> AST2600_I2CC_BUFF_CTRL));
> +			for (i = 0; i < xfer_len; i++)
> +				msg->buf[i2c_bus->master_xfer_cnt + i] =
> +					readb(i2c_bus->buf_base + 0x10 + i);
> +		} else {
> +			xfer_len = 1;
> +			msg->buf[i2c_bus->master_xfer_cnt] =
> +
AST2600_I2CC_GET_RX_BUFF(readl(i2c_bus->reg_base +
> +
AST2600_I2CC_STS_AND_BUFF));
> +		}
> +
> +		if (msg->flags & I2C_M_RECV_LEN) {
> +			msg->len = msg->buf[0] + ((msg->flags &
I2C_CLIENT_PEC) ? 2 :
> 1);
> +			msg->len = min_t(unsigned int, msg->len,
> I2C_SMBUS_BLOCK_MAX);
> +			msg->flags &= ~I2C_M_RECV_LEN;
> +		}
> +		i2c_bus->master_xfer_cnt += xfer_len;
> +
> +		if (i2c_bus->master_xfer_cnt == msg->len) {
> +			if (i2c_bus->mode == DMA_MODE) {
> +				dma_unmap_single(i2c_bus->dev,
> i2c_bus->master_dma_addr, msg->len,
> +						 DMA_FROM_DEVICE);
> +
i2c_put_dma_safe_msg_buf(i2c_bus->master_safe_buf,
> msg, true);
> +				i2c_bus->master_safe_buf = NULL;
> +			}
> +
> +			i2c_bus->msgs_index++;
> +			if (i2c_bus->msgs_index == i2c_bus->msgs_count) {
> +				i2c_bus->cmd_err = i2c_bus->msgs_index;
> +				complete(&i2c_bus->cmd_complete);
> +			} else {
> +				if (ast2600_i2c_do_start(i2c_bus)) {
> +					i2c_bus->cmd_err = -ENOMEM;
> +					complete(&i2c_bus->cmd_complete);
> +				}
> +			}
> +		} else {
> +			/* next rx */
> +			cmd |= AST2600_I2CM_RX_CMD;
> +			if (i2c_bus->mode == DMA_MODE) {
> +				cmd |= AST2600_I2CM_RX_DMA_EN;
> +				xfer_len = msg->len -
i2c_bus->master_xfer_cnt;
> +				if (xfer_len > AST2600_I2C_DMA_SIZE) {
> +					xfer_len = AST2600_I2C_DMA_SIZE;
> +				} else {
> +					if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +						cmd |=
MASTER_TRIGGER_LAST_STOP;
> +				}
> +				writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len
- 1),
> +				       i2c_bus->reg_base +
AST2600_I2CM_DMA_LEN);
> +				writel(i2c_bus->master_dma_addr +
> i2c_bus->master_xfer_cnt,
> +				       i2c_bus->reg_base +
AST2600_I2CM_RX_DMA);
> +			} else if (i2c_bus->mode == BUFF_MODE) {
> +				cmd |= AST2600_I2CM_RX_BUFF_EN;
> +				xfer_len = msg->len -
i2c_bus->master_xfer_cnt;
> +				if (xfer_len > i2c_bus->buf_size)
> +					xfer_len = i2c_bus->buf_size;
> +				else {
> +					if (i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count)
> +						cmd |=
MASTER_TRIGGER_LAST_STOP;
> +				}
> +
writel(AST2600_I2CC_SET_RX_BUF_LEN(xfer_len),
> +				       i2c_bus->reg_base +
AST2600_I2CC_BUFF_CTRL);
> +			} else {
> +				if ((i2c_bus->msgs_index + 1 ==
i2c_bus->msgs_count) &&
> +				    ((i2c_bus->master_xfer_cnt + 1) ==
msg->len)) {
> +					cmd |= MASTER_TRIGGER_LAST_STOP;
> +				}
> +			}
> +			writel(cmd, i2c_bus->reg_base +
AST2600_I2CM_CMD_STS);
> +		}
> +		break;
> +	default:
> +		dev_dbg(i2c_bus->dev, "unhandled sts %x\n", sts);
> +		break;
> +	}
> +}
> +
> +static int ast2600_i2c_master_irq(struct ast2600_i2c_bus *i2c_bus)
> +{
> +	u32 sts = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
> +	u32 ier = readl(i2c_bus->reg_base + AST2600_I2CM_IER);
> +	u32 ctrl = 0;
> +
> +	if (!i2c_bus->alert_enable)
> +		sts &= ~AST2600_I2CM_SMBUS_ALT;
> +
> +	if (AST2600_I2CM_BUS_RECOVER_FAIL & sts) {
> +		writel(AST2600_I2CM_BUS_RECOVER_FAIL, i2c_bus->reg_base +
> AST2600_I2CM_ISR);
> +		ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +		writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +		writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +		i2c_bus->cmd_err = -EPROTO;
> +		complete(&i2c_bus->cmd_complete);
> +		return 1;
> +	}
> +
> +	if (AST2600_I2CM_BUS_RECOVER & sts) {
> +		writel(AST2600_I2CM_BUS_RECOVER, i2c_bus->reg_base +
> AST2600_I2CM_ISR);
> +		i2c_bus->cmd_err = 0;
> +		complete(&i2c_bus->cmd_complete);
> +		return 1;
> +	}
> +
> +	if (AST2600_I2CM_SMBUS_ALT & sts) {
> +		if (ier & AST2600_I2CM_SMBUS_ALT) {
> +			/* Disable ALT INT */
> +			writel(ier & ~AST2600_I2CM_SMBUS_ALT,
i2c_bus->reg_base +
> AST2600_I2CM_IER);
> +			i2c_handle_smbus_alert(i2c_bus->ara);
> +			writel(AST2600_I2CM_SMBUS_ALT, i2c_bus->reg_base +
> AST2600_I2CM_ISR);
> +			dev_err(i2c_bus->dev,
> +				"ast2600_master_alert_recv bus id %d,
Disable Alt, Please
> Imple\n",
> +				i2c_bus->adap.nr);
> +			return 1;
> +		}
> +	}
> +
> +	i2c_bus->cmd_err = ast2600_i2c_is_irq_error(sts);
> +	if (i2c_bus->cmd_err) {
> +		writel(AST2600_I2CM_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CM_ISR);
> +		complete(&i2c_bus->cmd_complete);
> +		return 1;
> +	}
> +
> +	if (AST2600_I2CM_PKT_DONE & sts) {
> +		ast2600_i2c_master_package_irq(i2c_bus, sts);
> +		return 1;
> +	}
> +
> +	return 0;
> +}
> +
> +static irqreturn_t ast2600_i2c_bus_irq(int irq, void *dev_id)
> +{
> +	struct ast2600_i2c_bus *i2c_bus = dev_id;
> +
> +#ifdef CONFIG_I2C_SLAVE
> +	if (readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) &
> AST2600_I2CC_SLAVE_EN) {
> +		if (ast2600_i2c_slave_irq(i2c_bus))
> +			return IRQ_HANDLED;
> +	}
> +#endif
> +	return ast2600_i2c_master_irq(i2c_bus) ? IRQ_HANDLED : IRQ_NONE;
> +}
> +
> +static int ast2600_i2c_master_xfer(struct i2c_adapter *adap,
> +				      struct i2c_msg *msgs, int num)
> +{
> +	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(adap);
> +	unsigned long timeout;
> +	int ret = 0;
> +
> +	/* If bus is busy in a single master environment, attempt recovery.
*/
> +	if (!i2c_bus->multi_master &&
> +	    (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
> AST2600_I2CC_BUS_BUSY_STS)) {
> +		int ret;
> +
> +		ret = ast2600_i2c_recover_bus(i2c_bus);
> +		if (ret)
> +			return ret;
> +	}
> +
> +#ifdef CONFIG_I2C_SLAVE
> +	if (i2c_bus->mode == BUFF_MODE) {
> +		if (i2c_bus->slave_operate)
> +			return -EBUSY;
> +		/* disable slave isr */
> +		writel(0, i2c_bus->reg_base + AST2600_I2CS_IER);
> +		if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR) ||
> (i2c_bus->slave_operate)) {
> +			writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_IER);
> +			return -EBUSY;
> +		}
> +	}
> +#endif
> +
> +	i2c_bus->cmd_err = 0;
> +	i2c_bus->msgs = msgs;
> +	i2c_bus->msgs_index = 0;
> +	i2c_bus->msgs_count = num;
> +	reinit_completion(&i2c_bus->cmd_complete);
> +	ret = ast2600_i2c_do_start(i2c_bus);
> +#ifdef CONFIG_I2C_SLAVE
> +	/* avoid race condication slave is wait and master wait 1st slave
operate
> */
> +	if (i2c_bus->mode == BUFF_MODE)
> +		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_IER);
> +#endif
> +	if (ret)
> +		goto master_out;
> +	timeout = wait_for_completion_timeout(&i2c_bus->cmd_complete,
> i2c_bus->adap.timeout);
> +	if (timeout == 0) {
> +		u32 isr = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
> +		u32 i2c_status = readl(i2c_bus->reg_base +
> AST2600_I2CC_STS_AND_BUFF);
> +
> +		dev_dbg(i2c_bus->dev, "timeout isr[%x], sts[%x]\n", isr,
i2c_status);
> +		if (isr || (i2c_status & AST2600_I2CC_TX_DIR_MASK)) {
> +			u32 ctrl = readl(i2c_bus->reg_base +
> AST2600_I2CC_FUN_CTRL);
> +
> +			writel(0, i2c_bus->reg_base +
AST2600_I2CC_FUN_CTRL);
> +			writel(ctrl, i2c_bus->reg_base +
AST2600_I2CC_FUN_CTRL);
> +#ifdef CONFIG_I2C_SLAVE
> +			if (ctrl & AST2600_I2CC_SLAVE_EN) {
> +				u32 cmd = SLAVE_TRIGGER_CMD;
> +
> +				if (i2c_bus->mode == DMA_MODE) {
> +					cmd |= AST2600_I2CS_RX_DMA_EN;
> +					writel(i2c_bus->slave_dma_addr,
> +						   i2c_bus->reg_base +
> AST2600_I2CS_RX_DMA);
> +					writel(i2c_bus->slave_dma_addr,
> +						   i2c_bus->reg_base +
> AST2600_I2CS_TX_DMA);
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +						   i2c_bus->reg_base +
> AST2600_I2CS_DMA_LEN);
> +				} else if (i2c_bus->mode == BUFF_MODE) {
> +					cmd = SLAVE_TRIGGER_CMD;
> +				} else {
> +					cmd &= ~AST2600_I2CS_PKT_MODE_EN;
> +				}
> +				writel(cmd, i2c_bus->reg_base +
> AST2600_I2CS_CMD_STS);
> +			}
> +#endif
> +		}
> +		ret = -ETIMEDOUT;
> +	} else {
> +		ret = i2c_bus->cmd_err;
> +	}
> +
> +	dev_dbg(i2c_bus->dev, "bus%d-m: %d end\n", i2c_bus->adap.nr,
> i2c_bus->cmd_err);
> +
> +master_out:
> +	if (i2c_bus->mode == DMA_MODE) {
> +		kfree(i2c_bus->master_safe_buf);
> +	    i2c_bus->master_safe_buf = NULL;
> +	}
> +
> +	return ret;
> +}
> +
> +static void ast2600_i2c_init(struct ast2600_i2c_bus *i2c_bus)
> +{
> +	struct platform_device *pdev = to_platform_device(i2c_bus->dev);
> +	u32 fun_ctrl = AST2600_I2CC_BUS_AUTO_RELEASE |
> AST2600_I2CC_MASTER_EN;
> +
> +	/* I2C Reset */
> +	writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> +	if (of_property_read_bool(pdev->dev.of_node, "multi-master"))
> +		i2c_bus->multi_master = true;
> +	else
> +		fun_ctrl |= AST2600_I2CC_MULTI_MASTER_DIS;
> +
> +	/* Enable Master Mode */
> +	writel(fun_ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +	/* disable slave address */
> +	writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> +
> +	/* Set AC Timing */
> +	writel(ast2600_select_i2c_clock(i2c_bus), i2c_bus->reg_base +
> AST2600_I2CC_AC_TIMING);
> +
> +	/* Clear Interrupt */
> +	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CM_ISR);
> +
> +#ifdef CONFIG_I2C_SLAVE
> +	/* for memory buffer initial */
> +	if (i2c_bus->mode == DMA_MODE) {
> +		i2c_bus->slave_dma_buf = dma_alloc_coherent(i2c_bus->dev,
> I2C_SLAVE_MSG_BUF_SIZE,
> +
&i2c_bus->slave_dma_addr,
> GFP_KERNEL);
> +		if (!i2c_bus->slave_dma_buf)
> +			return;
> +	}
> +
> +	writel(0xfffffff, i2c_bus->reg_base + AST2600_I2CS_ISR);
> +
> +	if (i2c_bus->mode == BYTE_MODE) {
> +		writel(0xffff, i2c_bus->reg_base + AST2600_I2CS_IER);
> +	} else {
> +		/* Set interrupt generation of I2C slave controller */
> +		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base +
> AST2600_I2CS_IER);
> +	}
> +#endif
> +}
> +
> +#ifdef CONFIG_I2C_SLAVE
> +static int ast2600_i2c_reg_slave(struct i2c_client *client)
> +{
> +	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(client->adapter);
> +	u32 cmd = SLAVE_TRIGGER_CMD;
> +
> +	if (i2c_bus->slave)
> +		return -EINVAL;
> +
> +	dev_dbg(i2c_bus->dev, "slave addr %x\n", client->addr);
> +
> +	writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> +	writel(AST2600_I2CC_SLAVE_EN | readl(i2c_bus->reg_base +
> AST2600_I2CC_FUN_CTRL),
> +	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +
> +	/* trigger rx buffer */
> +	if (i2c_bus->mode == DMA_MODE) {
> +		cmd |= AST2600_I2CS_RX_DMA_EN;
> +		writel(i2c_bus->slave_dma_addr, i2c_bus->reg_base +
> AST2600_I2CS_RX_DMA);
> +		writel(i2c_bus->slave_dma_addr, i2c_bus->reg_base +
> AST2600_I2CS_TX_DMA);
> +
> 	writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_SLAVE_MSG_BUF_SIZE),
> +		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
> +	} else if (i2c_bus->mode == BUFF_MODE) {
> +		cmd = SLAVE_TRIGGER_CMD;
> +	} else {
> +		cmd &= ~AST2600_I2CS_PKT_MODE_EN;
> +	}
> +
> +	writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
> +	i2c_bus->slave = client;
> +	/* Set slave addr. */
> +	writel(client->addr | AST2600_I2CS_ADDR1_ENABLE,
> +			i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> +
> +	return 0;
> +}
> +
> +static int ast2600_i2c_unreg_slave(struct i2c_client *slave)
> +{
> +	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(slave->adapter);
> +
> +	WARN_ON(!i2c_bus->slave);
> +
> +	/* Turn off slave mode. */
> +	writel(~AST2600_I2CC_SLAVE_EN & readl(i2c_bus->reg_base +
> AST2600_I2CC_FUN_CTRL),
> +	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +	writel(readl(i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL) &
> ~AST2600_I2CS_ADDR1_MASK,
> +	       i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
> +
> +	i2c_bus->slave = NULL;
> +
> +	return 0;
> +}
> +#endif
> +
> +static u32 ast2600_i2c_functionality(struct i2c_adapter *adap)
> +{
> +	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
> I2C_FUNC_SMBUS_BLOCK_DATA;
> +}
> +
> +static const struct i2c_algorithm i2c_ast2600_algorithm = {
> +	.master_xfer = ast2600_i2c_master_xfer,
> +#if IS_ENABLED(CONFIG_I2C_SLAVE)
> +	.reg_slave = ast2600_i2c_reg_slave,
> +	.unreg_slave = ast2600_i2c_unreg_slave,
> +#endif
> +	.functionality = ast2600_i2c_functionality,
> +};
> +
> +static const struct of_device_id ast2600_i2c_bus_of_table[] = {
> +	{
> +		.compatible = "aspeed,ast2600-i2cv2",
> +	},
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(of, ast2600_i2c_bus_of_table);
> +
> +static int ast2600_i2c_probe(struct platform_device *pdev)
> +{
> +	struct device_node *np = pdev->dev.of_node;
> +	struct device *dev = &pdev->dev;
> +	struct ast2600_i2c_bus *i2c_bus;
> +	struct resource *res;
> +	u32 global_ctrl;
> +	int ret = 0;
> +
> +	i2c_bus = devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL);
> +	if (!i2c_bus)
> +		return -ENOMEM;
> +
> +	i2c_bus->reg_base = devm_platform_ioremap_resource(pdev, 0);
> +	if (IS_ERR(i2c_bus->reg_base))
> +		return PTR_ERR(i2c_bus->reg_base);
> +
> +	i2c_bus->rst = devm_reset_control_get_shared(dev, NULL);
> +	if (IS_ERR(i2c_bus->rst))
> +		return dev_err_probe(dev, PTR_ERR(i2c_bus->rst), "Missing
reset
> ctrl\n");
> +
> +	reset_control_deassert(i2c_bus->rst);
> +
> +	i2c_bus->global_regs = syscon_regmap_lookup_by_phandle(np,
> "aspeed,global-regs");
> +	if (IS_ERR(i2c_bus->global_regs))
> +		return PTR_ERR(i2c_bus->global_regs);
> +
> +	regmap_read(i2c_bus->global_regs, AST2600_I2CG_CTRL, &global_ctrl);
> +	if ((global_ctrl & AST2600_GLOBAL_INIT) != AST2600_GLOBAL_INIT) {
> +		regmap_write(i2c_bus->global_regs, AST2600_I2CG_CTRL,
> AST2600_GLOBAL_INIT);
> +		regmap_write(i2c_bus->global_regs,
AST2600_I2CG_CLK_DIV_CTRL,
> I2CCG_DIV_CTRL);
> +	}
> +
> +	i2c_bus->slave_operate = 0;
> +	i2c_bus->dev = dev;
> +	i2c_bus->mode = BUFF_MODE;
> +
> +	if (of_property_read_bool(pdev->dev.of_node, "aspeed,enable-dma"))
> +		i2c_bus->mode = DMA_MODE;
> +
> +	if (i2c_bus->mode == BUFF_MODE) {
> +		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
> +		if (res && resource_size(res) >= 2) {
> +			i2c_bus->buf_base = devm_ioremap_resource(dev, res);
> +
> +			if (!IS_ERR_OR_NULL(i2c_bus->buf_base))
> +				i2c_bus->buf_size = resource_size(res)/2;
> +		} else
> +			i2c_bus->mode = BYTE_MODE;
> +	}
> +
> +	/* i2c timeout counter: use base clk4 1Mhz,
> +	 * per unit: 1/(1000/4096) = 4096us
> +	 */
> +	ret = of_property_read_u32(dev->of_node,
> +
"i2c-scl-clk-low-timeout-us",
> +							&i2c_bus->timeout);
> +	if (ret < 0)
> +		i2c_bus->timeout = 0;
> +	else
> +		i2c_bus->timeout /= 4096;
> +
> +	init_completion(&i2c_bus->cmd_complete);
> +
> +	i2c_bus->irq = platform_get_irq(pdev, 0);
> +	if (i2c_bus->irq < 0)
> +		return i2c_bus->irq;
> +
> +	platform_set_drvdata(pdev, i2c_bus);
> +
> +	i2c_bus->clk = devm_clk_get(i2c_bus->dev, NULL);
> +	if (IS_ERR(i2c_bus->clk))
> +		return dev_err_probe(i2c_bus->dev, PTR_ERR(i2c_bus->clk),
"Can't
> get clock\n");
> +
> +	i2c_bus->apb_clk = clk_get_rate(i2c_bus->clk);
> +
> +	ret = of_property_read_u32(dev->of_node, "clock-frequency",
> &i2c_bus->bus_frequency);
> +	if (ret < 0) {
> +		dev_warn(dev, "Could not read clock-frequency property\n");
> +		i2c_bus->bus_frequency = 100000;
> +	}
> +
> +	/* Initialize the I2C adapter */
> +	i2c_bus->adap.owner = THIS_MODULE;
> +	i2c_bus->adap.algo = &i2c_ast2600_algorithm;
> +	i2c_bus->adap.retries = 0;
> +	i2c_bus->adap.dev.parent = i2c_bus->dev;
> +	i2c_bus->adap.dev.of_node = dev->of_node;
> +	i2c_bus->adap.algo_data = i2c_bus;
> +	strscpy(i2c_bus->adap.name, pdev->name, sizeof(i2c_bus->adap.name));
> +	i2c_set_adapdata(&i2c_bus->adap, i2c_bus);
> +
> +	ast2600_i2c_init(i2c_bus);
> +
> +	ret = devm_request_irq(dev, i2c_bus->irq, ast2600_i2c_bus_irq, 0,
> +			       dev_name(dev), i2c_bus);
> +	if (ret < 0)
> +		return dev_err_probe(dev, ret, "Unable to request irq %d\n",
> i2c_bus->irq);
> +
> +	if (of_property_read_bool(dev->of_node, "smbus-alert")) {
> +		i2c_bus->alert_enable = 1;
> +		i2c_bus->ara = i2c_new_smbus_alert_device(&i2c_bus->adap,
> &i2c_bus->alert_data);
> +		if (!i2c_bus->ara)
> +			dev_warn(dev, "Failed to register ARA client\n");
> +
> +		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER |
> AST2600_I2CM_SMBUS_ALT,
> +		       i2c_bus->reg_base + AST2600_I2CM_IER);
> +	} else {
> +		i2c_bus->alert_enable = 0;
> +		/* Set interrupt generation of I2C master controller */
> +		writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
> +				i2c_bus->reg_base + AST2600_I2CM_IER);
> +	}
> +
> +	ret = i2c_add_adapter(&i2c_bus->adap);
> +	if (ret)
> +		return ret;
> +
> +	dev_info(dev, "%s [%d]: adapter [%d khz] mode [%d]\n",
> +		 dev->of_node->name, i2c_bus->adap.nr,
i2c_bus->bus_frequency /
> 1000,
> +		 i2c_bus->mode);
> +
> +	return 0;
> +}
> +
> +static int ast2600_i2c_remove(struct platform_device *pdev)
> +{
> +	struct ast2600_i2c_bus *i2c_bus = platform_get_drvdata(pdev);
> +
> +	/* Disable everything. */
> +	writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
> +	writel(0, i2c_bus->reg_base + AST2600_I2CM_IER);
> +
> +	i2c_del_adapter(&i2c_bus->adap);
> +	devm_free_irq(&pdev->dev, i2c_bus->irq, i2c_bus);
> +
> +#ifdef CONFIG_I2C_SLAVE
> +	/* for memory buffer initial */
> +	if (i2c_bus->mode == DMA_MODE)
> +		dma_free_coherent(i2c_bus->dev, I2C_SLAVE_MSG_BUF_SIZE,
> +				i2c_bus->slave_dma_buf,
i2c_bus->slave_dma_addr);
> +#endif
> +
> +	return 0;
> +}
> +
> +static struct platform_driver ast2600_i2c_bus_driver = {
> +	.probe = ast2600_i2c_probe,
> +	.remove = ast2600_i2c_remove,
> +	.driver = {
> +		.name = KBUILD_MODNAME,
> +		.of_match_table = ast2600_i2c_bus_of_table,
> +	},
> +};
> +module_platform_driver(ast2600_i2c_bus_driver);
> +
> +MODULE_AUTHOR("Ryan Chen <ryan_chen at aspeedtech.com>");
> +MODULE_DESCRIPTION("ASPEED AST2600 I2C Controller Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.34.1




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