[PATCH v15 2/3] i2c: aspeed: support AST2600 i2c new register mode driver
Ryan Chen
ryan_chen at aspeedtech.com
Mon Oct 7 14:52:34 AEDT 2024
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 new register mode have separate register
set to control i2c controller and target. This patch is for i2c
controller mode driver.
Signed-off-by: Ryan Chen <ryan_chen at aspeedtech.com>
---
drivers/i2c/busses/Kconfig | 11 +
drivers/i2c/busses/Makefile | 1 +
drivers/i2c/busses/i2c-ast2600.c | 1032 ++++++++++++++++++++++++++++++
3 files changed, 1044 insertions(+)
create mode 100644 drivers/i2c/busses/i2c-ast2600.c
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index a22f9125322a..abfb027350d4 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -410,6 +410,17 @@ 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 78d0561339e5..5665b60b1566 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -39,6 +39,7 @@ 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..17ba0ee77c27
--- /dev/null
+++ b/drivers/i2c/busses/i2c-ast2600.c
@@ -0,0 +1,1032 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ASPEED AST2600 new register set I2C controller driver
+ *
+ * Copyright (C) ASPEED Technology Inc.
+ */
+#include <asm/unaligned.h>
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/minmax.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/string_helpers.h>
+
+#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)
+/*
+ * 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 I2CCG_DIV_CTRL 0xC6411208
+
+/* 0x00 : I2CC Controller/Target 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 Controller/Target 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 Controller/Target 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 Controller/Target Pool Buffer Control Register */
+#define AST2600_I2CC_BUFF_CTRL 0x0C
+#define AST2600_I2CC_GET_RX_BUF_LEN(x) (((x) & GENMASK(29, 24)) >> 24)
+#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) & GENMASK(12, 8)) >> 8) + 1)
+
+/* 0x10 : I2CM Controller Interrupt Control Register */
+#define AST2600_I2CM_IER 0x10
+/* 0x14 : I2CM Controller 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 Controller 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 Controller 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 Target Interrupt Control Register */
+#define AST2600_I2CS_IER 0x20
+/* 0x24 : I2CS Target 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 Target 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_SET_TX_DMA_LEN(x) ((((x) - 1) & GENMASK(11, 0)) | BIT(15))
+
+/* I2CM Controller DMA Tx Buffer Register */
+#define AST2600_I2CM_TX_DMA 0x30
+/* I2CM Controller DMA Rx Buffer Register */
+#define AST2600_I2CM_RX_DMA 0x34
+/* I2CS Target DMA Tx Buffer Register */
+#define AST2600_I2CS_TX_DMA 0x38
+/* I2CS Target 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) & GENMASK(28, 16)) >> 16)
+
+/* 0x40 : Target 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_TARGET_MSG_BUF_SIZE 256
+
+#define AST2600_I2C_DMA_SIZE 4096
+
+#define CONTROLLER_TRIGGER_LAST_STOP (AST2600_I2CM_RX_CMD_LAST | AST2600_I2CM_STOP_CMD)
+#define TARGET_TRIGGER_CMD (AST2600_I2CS_ACTIVE_ALL | AST2600_I2CS_PKT_MODE_EN)
+
+#define AST_I2C_TIMEOUT_CLK 0x2
+
+enum xfer_mode {
+ BYTE_MODE,
+ 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;
+ struct clk *clk;
+ struct i2c_timings timing_info;
+ struct completion cmd_complete;
+ struct i2c_msg *msgs;
+ u8 *controller_dma_safe_buf;
+ dma_addr_t controller_dma_addr;
+ u32 apb_clk;
+ u32 timeout;
+ int irq;
+ int cmd_err;
+ int msgs_index;
+ int msgs_count;
+ int controller_xfer_cnt;
+ size_t buf_index;
+ size_t buf_size;
+ enum xfer_mode mode;
+ bool multi_master;
+ /* Buffer mode */
+ void __iomem *buf_base;
+ struct i2c_smbus_alert_setup alert_data;
+};
+
+static u32 ast2600_select_i2c_clock(struct ast2600_i2c_bus *i2c_bus)
+{
+ unsigned long base_clk[16];
+ int baseclk_idx = 0;
+ int divisor = 0;
+ u32 clk_div_reg;
+ u32 scl_low;
+ u32 scl_high;
+ u32 data;
+
+ regmap_read(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, &clk_div_reg);
+
+ for (int i = 0; i < ARRAY_SIZE(base_clk); i++) {
+ if (i == 0)
+ base_clk[i] = i2c_bus->apb_clk;
+ else if (i < 5)
+ base_clk[i] = (i2c_bus->apb_clk * 2) /
+ (((clk_div_reg >> ((i - 1) * 8)) & GENMASK(7, 0)) + 2);
+ else
+ base_clk[i] = base_clk[4] >> (i - 5);
+
+ if ((base_clk[i] / i2c_bus->timing_info.bus_freq_hz) <= 32) {
+ baseclk_idx = i;
+ divisor = DIV_ROUND_UP(base_clk[i], i2c_bus->timing_info.bus_freq_hz);
+ break;
+ }
+ }
+ baseclk_idx = min(baseclk_idx, 15);
+ divisor = min(divisor, 32);
+ scl_low = min(divisor * 9 / 16 - 1, 15);
+ scl_high = (divisor - scl_low - 2) & GENMASK(3, 0);
+ 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)
+{
+ u32 state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+ int ret = 0;
+ u32 ctrl;
+ int r;
+
+ dev_dbg(i2c_bus->dev, "%d-bus recovery bus [%x]\n", i2c_bus->adap.nr, state);
+
+ ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+ /* Disable controller */
+ 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");
+ writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+ return -ETIMEDOUT;
+ } else if (i2c_bus->cmd_err) {
+ dev_dbg(i2c_bus->dev, "recovery error\n");
+ ret = -EPROTO;
+ }
+ }
+
+ /* Recovery done */
+ state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+ if (state & AST2600_I2CC_BUS_BUSY_STS) {
+ dev_dbg(i2c_bus->dev, "Can't recover bus [%x]\n", state);
+ ret = -EPROTO;
+ }
+
+ /* restore original controller setting */
+ writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+ return ret;
+}
+
+static int ast2600_i2c_setup_dma_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+ int xfer_len;
+ int ret;
+
+ cmd |= AST2600_I2CM_PKT_EN;
+ xfer_len = msg->len - i2c_bus->controller_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;
+
+ if (cmd & AST2600_I2CM_START_CMD) {
+ cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+ i2c_bus->controller_dma_safe_buf = i2c_get_dma_safe_msg_buf(msg, 1);
+ if (!i2c_bus->controller_dma_safe_buf)
+ return -ENOMEM;
+ i2c_bus->controller_dma_addr =
+ dma_map_single(i2c_bus->dev, i2c_bus->controller_dma_safe_buf,
+ msg->len, DMA_TO_DEVICE);
+ ret = dma_mapping_error(i2c_bus->dev, i2c_bus->controller_dma_addr);
+ if (ret) {
+ i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf, msg, false);
+ i2c_bus->controller_dma_safe_buf = NULL;
+ return ret;
+ }
+ }
+
+ 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);
+ writel(i2c_bus->controller_dma_addr + i2c_bus->controller_xfer_cnt,
+ i2c_bus->reg_base + AST2600_I2CM_TX_DMA);
+ }
+
+ writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+ return 0;
+}
+
+static int ast2600_i2c_setup_buff_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+ u32 wbuf_dword;
+ int xfer_len;
+ int i;
+
+ cmd |= AST2600_I2CM_PKT_EN;
+ xfer_len = msg->len - i2c_bus->controller_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;
+
+ if (cmd & AST2600_I2CM_START_CMD)
+ cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+
+ if (xfer_len) {
+ cmd |= AST2600_I2CM_TX_BUFF_EN | AST2600_I2CM_TX_CMD;
+ /*
+ * The controller's buffer register supports dword writes only.
+ * Therefore, write dwords to the buffer register in a 4-byte aligned,
+ * and write the remaining unaligned data at the end.
+ */
+ for (i = 0; i < xfer_len; i += 4) {
+ int xfer_cnt = i2c_bus->controller_xfer_cnt + i;
+
+ switch (min(xfer_len - i, 4) % 4) {
+ case 1:
+ wbuf_dword = msg->buf[xfer_cnt];
+ break;
+ case 2:
+ wbuf_dword = get_unaligned_le16(&msg->buf[xfer_cnt]);
+ break;
+ case 3:
+ wbuf_dword = get_unaligned_le24(&msg->buf[xfer_cnt]);
+ break;
+ default:
+ wbuf_dword = get_unaligned_le32(&msg->buf[xfer_cnt]);
+ break;
+ }
+ writel(wbuf_dword, i2c_bus->buf_base + i);
+ }
+ writel(AST2600_I2CC_SET_TX_BUF_LEN(xfer_len),
+ i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+ }
+
+ writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+ return 0;
+}
+
+static int ast2600_i2c_setup_byte_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+ int xfer_len;
+
+ xfer_len = msg->len - i2c_bus->controller_xfer_cnt;
+
+ cmd |= AST2600_I2CM_PKT_EN;
+
+ if (cmd & AST2600_I2CM_START_CMD)
+ cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+
+ if ((i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) &&
+ ((i2c_bus->controller_xfer_cnt + 1) == msg->len))
+ cmd |= AST2600_I2CM_STOP_CMD;
+
+ if (xfer_len) {
+ cmd |= AST2600_I2CM_TX_CMD;
+ writel(msg->buf[i2c_bus->controller_xfer_cnt],
+ i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+ }
+
+ writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+ return 0;
+}
+
+static int ast2600_i2c_setup_dma_rx(struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+ int xfer_len;
+ u32 cmd;
+ int ret;
+
+ cmd = AST2600_I2CM_PKT_EN | AST2600_I2CM_PKT_ADDR(msg->addr) |
+ AST2600_I2CM_START_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 |= CONTROLLER_TRIGGER_LAST_STOP;
+ }
+ writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1), i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+ i2c_bus->controller_dma_safe_buf = i2c_get_dma_safe_msg_buf(msg, 1);
+ if (!i2c_bus->controller_dma_safe_buf)
+ return -ENOMEM;
+ i2c_bus->controller_dma_addr =
+ dma_map_single(i2c_bus->dev, i2c_bus->controller_dma_safe_buf,
+ msg->len, DMA_FROM_DEVICE);
+ ret = dma_mapping_error(i2c_bus->dev, i2c_bus->controller_dma_addr);
+ if (ret) {
+ i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf, msg, false);
+ i2c_bus->controller_dma_safe_buf = NULL;
+ return ret;
+ }
+ writel(i2c_bus->controller_dma_addr, i2c_bus->reg_base + AST2600_I2CM_RX_DMA);
+
+ writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+ return 0;
+}
+
+static int ast2600_i2c_setup_buff_rx(struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+ int xfer_len;
+ u32 cmd;
+
+ cmd = AST2600_I2CM_PKT_EN | AST2600_I2CM_PKT_ADDR(msg->addr) |
+ AST2600_I2CM_START_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 |= CONTROLLER_TRIGGER_LAST_STOP;
+ }
+ writel(AST2600_I2CC_SET_RX_BUF_LEN(xfer_len), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+
+ writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+ return 0;
+}
+
+static int ast2600_i2c_setup_byte_rx(struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+ u32 cmd;
+
+ cmd = AST2600_I2CM_PKT_EN | AST2600_I2CM_PKT_ADDR(msg->addr) |
+ AST2600_I2CM_START_CMD | AST2600_I2CM_RX_CMD;
+
+ 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 |= CONTROLLER_TRIGGER_LAST_STOP;
+ }
+
+ writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+ return 0;
+}
+
+static int ast2600_i2c_do_start(struct ast2600_i2c_bus *i2c_bus)
+{
+ struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+
+ /* send start */
+ dev_dbg(i2c_bus->dev, "[%d] %s %d byte%s %s 0x%02x\n",
+ i2c_bus->msgs_index, str_read_write(msg->flags & I2C_M_RD),
+ msg->len, str_plural(msg->len),
+ msg->flags & I2C_M_RD ? "from" : "to", msg->addr);
+
+ i2c_bus->controller_xfer_cnt = 0;
+ i2c_bus->buf_index = 0;
+
+ if (msg->flags & I2C_M_RD) {
+ if (i2c_bus->mode == DMA_MODE)
+ return ast2600_i2c_setup_dma_rx(i2c_bus);
+ else if (i2c_bus->mode == BUFF_MODE)
+ return ast2600_i2c_setup_buff_rx(i2c_bus);
+ else
+ return ast2600_i2c_setup_byte_rx(i2c_bus);
+ } else {
+ if (i2c_bus->mode == DMA_MODE)
+ return ast2600_i2c_setup_dma_tx(AST2600_I2CM_START_CMD, i2c_bus);
+ else if (i2c_bus->mode == BUFF_MODE)
+ return ast2600_i2c_setup_buff_tx(AST2600_I2CM_START_CMD, i2c_bus);
+ else
+ return ast2600_i2c_setup_byte_tx(AST2600_I2CM_START_CMD, i2c_bus);
+ }
+}
+
+static int ast2600_i2c_irq_err_to_errno(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_controller_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->controller_xfer_cnt += xfer_len;
+
+ if (i2c_bus->controller_xfer_cnt == msg->len) {
+ if (i2c_bus->mode == DMA_MODE) {
+ dma_unmap_single(i2c_bus->dev, i2c_bus->controller_dma_addr,
+ msg->len, DMA_TO_DEVICE);
+ i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf,
+ msg, true);
+ i2c_bus->controller_dma_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 {
+ if (i2c_bus->mode == DMA_MODE)
+ ast2600_i2c_setup_dma_tx(0, i2c_bus);
+ else if (i2c_bus->mode == BUFF_MODE)
+ ast2600_i2c_setup_buff_tx(0, i2c_bus);
+ else
+ ast2600_i2c_setup_byte_tx(0, i2c_bus);
+ }
+ break;
+ case AST2600_I2CM_RX_DONE:
+ 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->controller_xfer_cnt + i] =
+ readb(i2c_bus->buf_base + 0x10 + i);
+ } else {
+ xfer_len = 1;
+ msg->buf[i2c_bus->controller_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 = min_t(unsigned int, msg->buf[0], I2C_SMBUS_BLOCK_MAX);
+ msg->len += ((msg->flags & I2C_CLIENT_PEC) ? 2 : 1);
+ msg->flags &= ~I2C_M_RECV_LEN;
+ }
+ i2c_bus->controller_xfer_cnt += xfer_len;
+
+ if (i2c_bus->controller_xfer_cnt == msg->len) {
+ if (i2c_bus->mode == DMA_MODE) {
+ dma_unmap_single(i2c_bus->dev, i2c_bus->controller_dma_addr,
+ msg->len, DMA_FROM_DEVICE);
+ i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf,
+ msg, true);
+ i2c_bus->controller_dma_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->controller_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 |= CONTROLLER_TRIGGER_LAST_STOP;
+ }
+ writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1),
+ i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+ writel(i2c_bus->controller_dma_addr + i2c_bus->controller_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->controller_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 |= CONTROLLER_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->controller_xfer_cnt + 1) == msg->len)) {
+ cmd |= CONTROLLER_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_controller_irq(struct ast2600_i2c_bus *i2c_bus)
+{
+ u32 sts = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
+ u32 ctrl;
+
+ 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;
+ }
+
+ i2c_bus->cmd_err = ast2600_i2c_irq_err_to_errno(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_controller_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;
+
+ return IRQ_RETVAL(ast2600_i2c_controller_irq(i2c_bus));
+}
+
+static int ast2600_i2c_controller_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;
+
+ if (!i2c_bus->multi_master &&
+ (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) & AST2600_I2CC_BUS_BUSY_STS)) {
+ ret = ast2600_i2c_recover_bus(i2c_bus);
+ if (ret)
+ return ret;
+ }
+
+ 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);
+ if (ret)
+ goto controller_out;
+ timeout = wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.timeout);
+ if (timeout == 0) {
+ u32 ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+ dev_dbg(i2c_bus->dev, "timeout isr[%x], sts[%x]\n",
+ readl(i2c_bus->reg_base + AST2600_I2CM_ISR),
+ readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+ writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+ writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+ if (i2c_bus->multi_master &&
+ (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
+ AST2600_I2CC_BUS_BUSY_STS))
+ ast2600_i2c_recover_bus(i2c_bus);
+
+ 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);
+
+controller_out:
+ if (i2c_bus->mode == DMA_MODE) {
+ kfree(i2c_bus->controller_dma_safe_buf);
+ i2c_bus->controller_dma_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);
+
+ i2c_bus->multi_master = device_property_read_bool(&pdev->dev, "multi-master");
+ if (!i2c_bus->multi_master)
+ fun_ctrl |= AST2600_I2CC_MULTI_MASTER_DIS;
+
+ /* Enable Controller Mode */
+ writel(fun_ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+ /* disable target 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(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CM_ISR);
+}
+
+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 = {
+ .xfer = ast2600_i2c_controller_xfer,
+ .functionality = ast2600_i2c_functionality,
+};
+
+static int ast2600_i2c_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ast2600_i2c_bus *i2c_bus;
+ struct resource *res;
+ u32 global_ctrl;
+ int ret;
+
+ 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(dev_of_node(dev), "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->dev = dev;
+ i2c_bus->mode = BUFF_MODE;
+
+ if (device_property_read_bool(dev, "aspeed,enable-dma"))
+ i2c_bus->mode = DMA_MODE;
+
+ if (i2c_bus->mode == BUFF_MODE) {
+ i2c_bus->buf_base = devm_platform_get_and_ioremap_resource(pdev, 1, &res);
+ if (IS_ERR(i2c_bus->buf_base))
+ i2c_bus->mode = BYTE_MODE;
+ else
+ i2c_bus->buf_size = resource_size(res) / 2;
+ }
+
+ /*
+ * i2c timeout counter: use base clk4 1Mhz,
+ * per unit: 1/(1000/4096) = 4096us
+ */
+ ret = device_property_read_u32(dev, "i2c-scl-clk-low-timeout-us", &i2c_bus->timeout);
+ if (!ret)
+ 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);
+
+ i2c_parse_fw_timings(i2c_bus->dev, &i2c_bus->timing_info, true);
+
+ /* 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;
+ device_set_node(&i2c_bus->adap.dev, dev_fwnode(dev));
+ i2c_bus->adap.algo_data = i2c_bus;
+ strscpy(i2c_bus->adap.name, pdev->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);
+
+ writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
+ i2c_bus->reg_base + AST2600_I2CM_IER);
+
+ ret = devm_i2c_add_adapter(dev, &i2c_bus->adap);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+static void 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);
+}
+
+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 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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