[PATCH v3 1/5] i2c: mediatek: add basic driver support
mingming lee
mingming.lee at mediatek.com
Fri Oct 16 05:27:11 CEST 2020
From: Mingming Lee <Mingming.Lee at mediatek.com>
Add MediaTek I2C basic driver
Reviewed-by: Heiko Schocher <hs at denx.de>
Signed-off-by: Mingming Lee <Mingming.Lee at mediatek.com>
---
Changes for v3:
- fixed code veriew note in v2
- optimize the dma read/write flow in mtk_i2c_do_transfer()
Changes for v2:
- using error number defined in include/linux/errno.h
---
drivers/i2c/Kconfig | 8 +
drivers/i2c/Makefile | 1 +
drivers/i2c/mt_i2c.c | 713 +++++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 722 insertions(+)
create mode 100644 drivers/i2c/mt_i2c.c
diff --git a/drivers/i2c/Kconfig b/drivers/i2c/Kconfig
index dec6dc9..e217673 100644
--- a/drivers/i2c/Kconfig
+++ b/drivers/i2c/Kconfig
@@ -159,6 +159,14 @@ config SYS_I2C_MESON
internal buffer holding up to 8 bytes for transfers and supports
both 7-bit and 10-bit addresses.
+config SYS_I2C_MTK
+ bool "MediaTek I2C driver"
+ help
+ This selects the MediaTek Integrated Inter Circuit bus driver.
+ The I2C bus adapter is the base for some other I2C client, eg: touch, sensors.
+ If you want to use MediaTek I2C interface, say Y here.
+ If unsure, say N.
+
config SYS_I2C_MXC
bool "NXP MXC I2C driver"
help
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index e851ec4..7227742 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_SYS_I2C_LPC32XX) += lpc32xx_i2c.o
obj-$(CONFIG_SYS_I2C_MESON) += meson_i2c.o
obj-$(CONFIG_SYS_I2C_MVTWSI) += mvtwsi.o
obj-$(CONFIG_SYS_I2C_MXC) += mxc_i2c.o
+obj-$(CONFIG_SYS_I2C_MTK) += mt_i2c.o
obj-$(CONFIG_SYS_I2C_NEXELL) += nx_i2c.o
obj-$(CONFIG_SYS_I2C_OCTEON) += octeon_i2c.o
obj-$(CONFIG_SYS_I2C_OMAP24XX) += omap24xx_i2c.o
diff --git a/drivers/i2c/mt_i2c.c b/drivers/i2c/mt_i2c.c
new file mode 100644
index 0000000..e1de933
--- /dev/null
+++ b/drivers/i2c/mt_i2c.c
@@ -0,0 +1,713 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MediaTek I2C Interface driver
+ *
+ * Copyright (C) 2020 MediaTek Inc.
+ * Author: Mingming Lee <Mingming.Lee at mediatek.com>
+ */
+
+#include <common.h>
+#include <clk.h>
+#include <cpu_func.h>
+#include <dm.h>
+#include <i2c.h>
+#include <log.h>
+#include <asm/cache.h>
+#include <asm/io.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+
+#define I2C_RS_TRANSFER BIT(4)
+#define I2C_HS_NACKERR BIT(2)
+#define I2C_ACKERR BIT(1)
+#define I2C_TRANSAC_COMP BIT(0)
+#define I2C_TRANSAC_START BIT(0)
+#define I2C_RS_MUL_CNFG BIT(15)
+#define I2C_RS_MUL_TRIG BIT(14)
+#define I2C_DCM_DISABLE 0x0000
+#define I2C_IO_CONFIG_OPEN_DRAIN 0x0003
+#define I2C_IO_CONFIG_PUSH_PULL 0x0000
+#define I2C_SOFT_RST 0x0001
+#define I2C_FIFO_ADDR_CLR 0x0001
+#define I2C_DELAY_LEN 0x0002
+#define I2C_ST_START_CON 0x8001
+#define I2C_FS_START_CON 0x1800
+#define I2C_TIME_CLR_VALUE 0x0000
+#define I2C_TIME_DEFAULT_VALUE 0x0003
+#define I2C_WRRD_TRANAC_VALUE 0x0002
+#define I2C_RD_TRANAC_VALUE 0x0001
+
+#define I2C_DMA_CON_TX 0x0000
+#define I2C_DMA_CON_RX 0x0001
+#define I2C_DMA_START_EN 0x0001
+#define I2C_DMA_INT_FLAG_NONE 0x0000
+#define I2C_DMA_CLR_FLAG 0x0000
+#define I2C_DMA_TX_RX 0x0000
+#define I2C_DMA_HARD_RST 0x0002
+
+#define MAX_ST_MODE_SPEED 100000
+#define MAX_FS_MODE_SPEED 400000
+#define MAX_HS_MODE_SPEED 3400000
+#define MAX_SAMPLE_CNT_DIV 8
+#define MAX_STEP_CNT_DIV 64
+#define MAX_HS_STEP_CNT_DIV 8
+#define I2C_DEFAULT_CLK_DIV 4
+
+#define MAX_I2C_ADDR 0x7f
+#define MAX_I2C_LEN 0xff
+#define TRANS_ADDR_ONLY BIT(8)
+#define TRANSFER_TIMEOUT 50000 /* us */
+#define I2C_FIFO_STAT1_MASK 0x001f
+#define TIMING_SAMPLE_OFFSET 8
+#define HS_SAMPLE_OFFSET 12
+#define HS_STEP_OFFSET 8
+
+#define I2C_CONTROL_WRAPPER BIT(0)
+#define I2C_CONTROL_RS BIT(1)
+#define I2C_CONTROL_DMA_EN BIT(2)
+#define I2C_CONTROL_CLK_EXT_EN BIT(3)
+#define I2C_CONTROL_DIR_CHANGE BIT(4)
+#define I2C_CONTROL_ACKERR_DET_EN BIT(5)
+#define I2C_CONTROL_TRANSFER_LEN_CHANGE BIT(6)
+#define I2C_CONTROL_DMAACK BIT(8)
+#define I2C_CONTROL_ASYNC BIT(9)
+
+enum I2C_REGS_OFFSET {
+ REG_PORT = 0x0,
+ REG_SLAVE_ADDR = 0x04,
+ REG_INTR_MASK = 0x08,
+ REG_INTR_STAT = 0x0c,
+ REG_CONTROL = 0x10,
+ REG_TRANSFER_LEN = 0x14,
+ REG_TRANSAC_LEN = 0x18,
+ REG_DELAY_LEN = 0x1c,
+ REG_TIMING = 0x20,
+ REG_START = 0x24,
+ REG_EXT_CONF = 0x28,
+ REG_FIFO_STAT1 = 0x2c,
+ REG_FIFO_STAT = 0x30,
+ REG_FIFO_THRESH = 0x34,
+ REG_FIFO_ADDR_CLR = 0x38,
+ REG_IO_CONFIG = 0x40,
+ REG_RSV_DEBUG = 0x44,
+ REG_HS = 0x48,
+ REG_SOFTRESET = 0x50,
+ REG_DCM_EN = 0x54,
+ REG_DEBUGSTAT = 0x64,
+ REG_DEBUGCTRL = 0x68,
+ REG_TRANSFER_LEN_AUX = 0x6c,
+ REG_CLOCK_DIV = 0x70,
+ REG_SCL_HL_RATIO = 0x74,
+ REG_SCL_HS_HL_RATIO = 0x78,
+ REG_SCL_MIS_COMP_POINT = 0x7c,
+ REG_STA_STOP_AC_TIME = 0x80,
+ REG_HS_STA_STOP_AC_TIME = 0x84,
+ REG_DATA_TIME = 0x88,
+};
+
+enum DMA_REGS_OFFSET {
+ REG_INT_FLAG = 0x0,
+ REG_INT_EN = 0x04,
+ REG_EN = 0x08,
+ REG_RST = 0x0c,
+ REG_CON = 0x18,
+ REG_TX_MEM_ADDR = 0x1c,
+ REG_RX_MEM_ADDR = 0x20,
+ REG_TX_LEN = 0x24,
+ REG_RX_LEN = 0x28,
+};
+
+enum mtk_trans_op {
+ I2C_MASTER_WR = 1,
+ I2C_MASTER_RD,
+ I2C_MASTER_WRRD,
+};
+
+struct mtk_i2c_soc_data {
+ uint dma_sync: 1;
+};
+
+struct mtk_i2c_priv {
+ /* set in i2c probe */
+ void __iomem *base; /* i2c base addr */
+ void __iomem *pdmabase; /* dma base address*/
+ struct clk clk_main; /* main clock for i2c bus */
+ struct clk clk_dma; /* DMA clock for i2c via DMA */
+ const struct mtk_i2c_soc_data *soc_data; /* Compatible data for different IC */
+ enum mtk_trans_op op; /* operation mode */
+ bool zero_len; /* Only transfer slave address, no data */
+ bool pushpull; /* push pull mode or open drain mode */
+ bool filter_msg; /* filter msg error log */
+ bool auto_restart; /* restart mode */
+ bool ignore_restart_irq; /* ignore restart IRQ */
+ uint speed; /* i2c speed, unit: hz */
+};
+
+static inline void i2c_writel(struct mtk_i2c_priv *priv, uint offset, uint value)
+{
+ writel(value, (priv->base + offset));
+}
+
+static inline uint i2c_readl(struct mtk_i2c_priv *priv, uint offset)
+{
+ return readl(priv->base + offset);
+}
+
+static int mtk_i2c_clk_enable(struct mtk_i2c_priv *priv)
+{
+ int ret;
+
+ ret = clk_enable(&priv->clk_main);
+ if (ret)
+ return log_msg_ret("enable clk_main", ret);
+
+ ret = clk_enable(&priv->clk_dma);
+ if (ret)
+ return log_msg_ret("enable clk_dma", ret);
+
+ return 0;
+}
+
+static int mtk_i2c_clk_disable(struct mtk_i2c_priv *priv)
+{
+ int ret;
+
+ ret = clk_disable(&priv->clk_dma);
+ if (ret)
+ return log_msg_ret("disable clk_dma", ret);
+
+ ret = clk_disable(&priv->clk_main);
+ if (ret)
+ return log_msg_ret("disable clk_main", ret);
+
+ return 0;
+}
+
+static void mtk_i2c_init_hw(struct mtk_i2c_priv *priv)
+{
+ uint control_reg;
+
+ writel(I2C_DMA_HARD_RST, priv->pdmabase + REG_RST);
+ writel(I2C_DMA_CLR_FLAG, priv->pdmabase + REG_RST);
+ i2c_writel(priv, REG_SOFTRESET, I2C_SOFT_RST);
+ /* set ioconfig */
+ if (priv->pushpull)
+ i2c_writel(priv, REG_IO_CONFIG, I2C_IO_CONFIG_PUSH_PULL);
+ else
+ i2c_writel(priv, REG_IO_CONFIG, I2C_IO_CONFIG_OPEN_DRAIN);
+
+ i2c_writel(priv, REG_DCM_EN, I2C_DCM_DISABLE);
+ control_reg = I2C_CONTROL_ACKERR_DET_EN | I2C_CONTROL_CLK_EXT_EN;
+ if (priv->soc_data->dma_sync)
+ control_reg |= I2C_CONTROL_DMAACK | I2C_CONTROL_ASYNC;
+ i2c_writel(priv, REG_CONTROL, control_reg);
+ i2c_writel(priv, REG_DELAY_LEN, I2C_DELAY_LEN);
+}
+
+/*
+ * Calculate i2c port speed
+ *
+ * Hardware design:
+ * i2c_bus_freq = parent_clk / (clock_div * 2 * sample_cnt * step_cnt)
+ * clock_div: fixed in hardware, but may be various in different SoCs
+ *
+ * The calculation want to pick the highest bus frequency that is still
+ * less than or equal to target_speed. The calculation try to get
+ * sample_cnt and step_cn
+ * @param[in]
+ * clk_src: i2c clock source
+ * @param[out]
+ * timing_step_cnt: step cnt calculate result
+ * @param[out]
+ * timing_sample_cnt: sample cnt calculate result
+ * @return
+ * 0, set speed successfully.
+ * -EINVAL, Unsupported speed.
+ */
+static int mtk_i2c_calculate_speed(uint clk_src,
+ uint target_speed,
+ uint *timing_step_cnt,
+ uint *timing_sample_cnt)
+{
+ uint step_cnt;
+ uint sample_cnt;
+ uint max_step_cnt;
+ uint base_sample_cnt = MAX_SAMPLE_CNT_DIV;
+ uint base_step_cnt;
+ uint opt_div;
+ uint best_mul;
+ uint cnt_mul;
+
+ if (target_speed > MAX_HS_MODE_SPEED)
+ target_speed = MAX_HS_MODE_SPEED;
+
+ if (target_speed > MAX_FS_MODE_SPEED)
+ max_step_cnt = MAX_HS_STEP_CNT_DIV;
+ else
+ max_step_cnt = MAX_STEP_CNT_DIV;
+
+ base_step_cnt = max_step_cnt;
+ /* Find the best combination */
+ opt_div = DIV_ROUND_UP(clk_src >> 1, target_speed);
+ best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt;
+
+ /*
+ * Search for the best pair (sample_cnt, step_cnt) with
+ * 0 < sample_cnt < MAX_SAMPLE_CNT_DIV
+ * 0 < step_cnt < max_step_cnt
+ * sample_cnt * step_cnt >= opt_div
+ * optimizing for sample_cnt * step_cnt being minimal
+ */
+ for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) {
+ step_cnt = DIV_ROUND_UP(opt_div, sample_cnt);
+ cnt_mul = step_cnt * sample_cnt;
+ if (step_cnt > max_step_cnt)
+ continue;
+
+ if (cnt_mul < best_mul) {
+ best_mul = cnt_mul;
+ base_sample_cnt = sample_cnt;
+ base_step_cnt = step_cnt;
+ if (best_mul == opt_div)
+ break;
+ }
+ }
+
+ sample_cnt = base_sample_cnt;
+ step_cnt = base_step_cnt;
+
+ if ((clk_src / (2 * sample_cnt * step_cnt)) > target_speed) {
+ /*
+ * In this case, hardware can't support such
+ * low i2c_bus_freq
+ */
+ debug("Unsupported speed(%uhz)\n", target_speed);
+ return log_msg_ret("calculate speed", -EINVAL);
+ }
+
+ *timing_step_cnt = step_cnt - 1;
+ *timing_sample_cnt = sample_cnt - 1;
+
+ return 0;
+}
+
+/*
+ * mtk_i2c_set_speed
+ *
+ * @par Description
+ * Calculate i2c speed and write sample_cnt, step_cnt to TIMING register.
+ * @param[in]
+ * dev: udevice pointer, struct udevice contains i2c source clock,
+ * clock divide and speed.
+ * @return
+ * 0, set speed successfully.\n
+ * error code from mtk_i2c_calculate_speed().
+ */
+static int mtk_i2c_set_speed(struct udevice *dev, uint speed)
+{
+ uint clk_src;
+ uint step_cnt;
+ uint sample_cnt;
+ uint timing_reg;
+ uint high_speed_reg;
+ int ret = 0;
+ struct mtk_i2c_priv *priv = dev_get_priv(dev);
+
+ priv->speed = speed;
+ if (mtk_i2c_clk_enable(priv))
+ return log_msg_ret("set_speed enable clk", -1);
+
+ clk_src = clk_get_rate(&priv->clk_main) / I2C_DEFAULT_CLK_DIV;
+ i2c_writel(priv, REG_CLOCK_DIV, (I2C_DEFAULT_CLK_DIV - 1));
+ if (priv->speed > MAX_FS_MODE_SPEED) {
+ /* Set master code speed register */
+ ret = mtk_i2c_calculate_speed(clk_src, MAX_FS_MODE_SPEED,
+ &step_cnt, &sample_cnt);
+ if (ret < 0)
+ goto exit;
+
+ timing_reg = (sample_cnt << TIMING_SAMPLE_OFFSET) | step_cnt;
+ writel(timing_reg, priv->base + REG_TIMING);
+ /* Set the high speed mode register */
+ ret = mtk_i2c_calculate_speed(clk_src, priv->speed,
+ &step_cnt, &sample_cnt);
+ if (ret < 0)
+ goto exit;
+
+ high_speed_reg = I2C_TIME_DEFAULT_VALUE |
+ (sample_cnt << HS_SAMPLE_OFFSET) |
+ (step_cnt << HS_STEP_OFFSET);
+ writel(high_speed_reg, priv->base + REG_HS);
+ } else {
+ ret = mtk_i2c_calculate_speed(clk_src, priv->speed,
+ &step_cnt, &sample_cnt);
+ if (ret < 0)
+ goto exit;
+
+ timing_reg = (sample_cnt << TIMING_SAMPLE_OFFSET) | step_cnt;
+ /* Disable the high speed transaction */
+ high_speed_reg = I2C_TIME_CLR_VALUE;
+ writel(timing_reg, priv->base + REG_TIMING);
+ writel(high_speed_reg, priv->base + REG_HS);
+ }
+exit:
+ if (mtk_i2c_clk_disable(priv))
+ return log_msg_ret("set_speed disable clk", -1);
+
+ return ret;
+}
+
+/*
+ * mtk_i2c_do_transfer
+ *
+ * @par Description
+ * Configure i2c register and trigger transfer.
+ * @param[in]
+ * priv: mtk_i2cmtk_i2c_priv pointer, struct mtk_i2c_priv contains register base\n
+ * address, operation mode, interrupt status and i2c driver data.
+ * @param[in]
+ * msgs: i2c_msg pointer, struct i2c_msg contains slave\n
+ * address, operation mode, msg length and data buffer.
+ * @param[in]
+ * num: i2c_msg number.
+ * @param[in]
+ * left_num: left i2c_msg number.
+ * @return
+ * 0, i2c transfer successfully.\n
+ * -ETIMEDOUT, i2c transfer timeout.\n
+ * -EREMOTEIO, i2c transfer ack error.
+ */
+static int mtk_i2c_do_transfer(struct mtk_i2c_priv *priv,
+ struct i2c_msg *msgs,
+ int num, int left_num)
+{
+ uint addr_reg;
+ uint start_reg;
+ uint control_reg;
+ uint restart_flag = 0;
+ uint irq_stat = 0;
+ uint trans_error = 0;
+ bool tmo = false;
+ uint tmo_poll = 0;
+ int ret = 0;
+
+ if (priv->auto_restart)
+ restart_flag = I2C_RS_TRANSFER;
+
+ control_reg = i2c_readl(priv, REG_CONTROL) &
+ ~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS);
+
+ if (priv->speed > MAX_FS_MODE_SPEED || num > 1)
+ control_reg |= I2C_CONTROL_RS;
+
+ if (priv->op == I2C_MASTER_WRRD)
+ control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS;
+
+ control_reg |= I2C_CONTROL_DMA_EN;
+ i2c_writel(priv, REG_CONTROL, control_reg);
+
+ /* set start condition */
+ if (priv->speed <= MAX_ST_MODE_SPEED)
+ i2c_writel(priv, REG_EXT_CONF, I2C_ST_START_CON);
+ else
+ i2c_writel(priv, REG_EXT_CONF, I2C_FS_START_CON);
+
+ addr_reg = msgs->addr << 1;
+ if (priv->op == I2C_MASTER_RD)
+ addr_reg |= I2C_M_RD;
+ if (priv->zero_len)
+ i2c_writel(priv, REG_SLAVE_ADDR, addr_reg | TRANS_ADDR_ONLY);
+ else
+ i2c_writel(priv, REG_SLAVE_ADDR, addr_reg);
+
+ /* clear interrupt status */
+ i2c_writel(priv, REG_INTR_STAT, restart_flag | I2C_HS_NACKERR |
+ I2C_ACKERR | I2C_TRANSAC_COMP);
+ i2c_writel(priv, REG_FIFO_ADDR_CLR, I2C_FIFO_ADDR_CLR);
+
+ /* enable interrupt */
+ i2c_writel(priv, REG_INTR_MASK, restart_flag | I2C_HS_NACKERR |
+ I2C_ACKERR | I2C_TRANSAC_COMP);
+
+ /* set transfer and transaction len */
+ if (priv->op == I2C_MASTER_WRRD) {
+ i2c_writel(priv, REG_TRANSFER_LEN, msgs->len);
+ i2c_writel(priv, REG_TRANSFER_LEN_AUX, (msgs + 1)->len);
+ i2c_writel(priv, REG_TRANSAC_LEN, I2C_WRRD_TRANAC_VALUE);
+ } else {
+ i2c_writel(priv, REG_TRANSFER_LEN, msgs->len);
+ i2c_writel(priv, REG_TRANSAC_LEN, num);
+ }
+
+ /*
+ * prepare buffer data to start transfer
+ * three cases here: read, write, write then read
+ */
+ if (priv->op == I2C_MASTER_RD) {
+ /* Clear DMA interrupt flag*/
+ writel(I2C_DMA_INT_FLAG_NONE, priv->pdmabase + REG_INT_FLAG);
+ /* Set DMA direction RX*/
+ writel(I2C_DMA_CON_RX, priv->pdmabase + REG_CON);
+ flush_cache((unsigned long)msgs->buf, msgs->len);
+ /* Write the rx buffer address to dma register*/
+ writel(msgs->buf, priv->pdmabase + REG_RX_MEM_ADDR);
+ /* Write the rx length to dma register*/
+ writel(msgs->len, priv->pdmabase + REG_RX_LEN);
+ } else if (priv->op == I2C_MASTER_WR) {
+ /* Clear DMA interrupt flag*/
+ writel(I2C_DMA_INT_FLAG_NONE, priv->pdmabase + REG_INT_FLAG);
+ /* Set DMA direction TX*/
+ writel(I2C_DMA_CON_TX, priv->pdmabase + REG_CON);
+ flush_cache((unsigned long)msgs->buf, msgs->len);
+ /* Write the tx buffer address to dma register*/
+ writel(msgs->buf, priv->pdmabase + REG_TX_MEM_ADDR);
+ /* Write the tx length to dma register*/
+ writel(msgs->len, priv->pdmabase + REG_TX_LEN);
+ } else {
+ /* Clear DMA interrupt flag*/
+ writel(I2C_DMA_INT_FLAG_NONE, priv->pdmabase + REG_INT_FLAG);
+ /* Set DMA direction TX and RX*/
+ writel(I2C_DMA_TX_RX, priv->pdmabase + REG_CON);
+ flush_cache((unsigned long)msgs->buf, msgs->len);
+ flush_cache((unsigned long)(msgs + 1)->buf, (msgs + 1)->len);
+ /* Write the tx buffer address to dma register*/
+ writel(msgs->buf, priv->pdmabase + REG_TX_MEM_ADDR);
+ /* Write the tx buffer address to dma register*/
+ writel((msgs + 1)->buf, priv->pdmabase + REG_RX_MEM_ADDR);
+ /* Write the tx length to dma register*/
+ writel(msgs->len, priv->pdmabase + REG_TX_LEN);
+ /* Write the rx length to dma register*/
+ writel((msgs + 1)->len, priv->pdmabase + REG_RX_LEN);
+ }
+
+ writel(I2C_DMA_START_EN, priv->pdmabase + REG_EN);
+
+ if (!priv->auto_restart) {
+ start_reg = I2C_TRANSAC_START;
+ } else {
+ start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG;
+ if (left_num >= 1)
+ start_reg |= I2C_RS_MUL_CNFG;
+ }
+ i2c_writel(priv, REG_START, start_reg);
+
+ for (;;) {
+ irq_stat = i2c_readl(priv, REG_INTR_STAT);
+
+ /* ignore the first restart irq after the master code */
+ if (priv->ignore_restart_irq && (irq_stat | restart_flag)) {
+ priv->ignore_restart_irq = false;
+ irq_stat = 0;
+ writel(I2C_RS_MUL_CNFG | I2C_RS_MUL_TRIG |
+ I2C_TRANSAC_START, priv->base + REG_START);
+ }
+
+ if (irq_stat & (I2C_TRANSAC_COMP | restart_flag)) {
+ tmo = false;
+ if (irq_stat & (I2C_HS_NACKERR | I2C_ACKERR))
+ trans_error = 1;
+
+ break;
+ }
+ udelay(1);
+ if (tmo_poll++ >= TRANSFER_TIMEOUT) {
+ tmo = true;
+ break;
+ }
+ }
+
+ /* clear interrupt mask */
+ i2c_writel(priv, REG_INTR_MASK, ~(restart_flag | I2C_HS_NACKERR |
+ I2C_ACKERR | I2C_TRANSAC_COMP));
+
+ if (!tmo && trans_error != 0) {
+ if (tmo) {
+ ret = -ETIMEDOUT;
+ if (!priv->filter_msg)
+ debug("I2C timeout! addr: 0x%x,\n", msgs->addr);
+ } else {
+ ret = -EREMOTEIO;
+ if (!priv->filter_msg)
+ debug("I2C ACKERR! addr: 0x%x,IRQ:0x%x\n",
+ msgs->addr, irq_stat);
+ }
+ mtk_i2c_init_hw(priv);
+ }
+
+ return ret;
+}
+
+/*
+ * mtk_i2c_transfer
+ *
+ * @par Description
+ * Common i2c transfer API. Set i2c transfer mode according to i2c_msg\n
+ * information, then call mtk_i2c_do_transfer() to configure i2c register\n
+ * and trigger transfer.
+ * @param[in]
+ * dev: udevice pointer, struct udevice contains struct mtk_i2c_priv, \n
+ * struct mtk_i2c_priv contains register base\n
+ * address, operation mode, interrupt status and i2c driver data.
+ * @param[in]
+ * msgs: i2c_msg pointer, struct i2c_msg contains slave\n
+ * address, operation mode, msg length and data buffer.
+ * @param[in]
+ * num: i2c_msg number.
+ * @return
+ * i2c_msg number, i2c transfer successfully.\n
+ * -EINVAL, msg length is more than 16\n
+ * use DMA MODE or slave address more than 0x7f.\n
+ * error code from mtk_i2c_init_base().\n
+ * error code from mtk_i2c_set_speed().\n
+ * error code from mtk_i2c_do_transfer().
+ */
+static int mtk_i2c_transfer(struct udevice *dev, struct i2c_msg *msg,
+ int nmsgs)
+{
+ int ret;
+ int left_num;
+ uint num_cnt;
+ struct mtk_i2c_priv *priv = dev_get_priv(dev);
+
+ priv->auto_restart = true;
+ left_num = nmsgs;
+ if (mtk_i2c_clk_enable(priv))
+ return log_msg_ret("transfer enable clk", -1);
+
+ for (num_cnt = 0; num_cnt < nmsgs; num_cnt++) {
+ if (((msg + num_cnt)->addr) > MAX_I2C_ADDR) {
+ ret = -EINVAL;
+ goto err_exit;
+ }
+ if ((msg + num_cnt)->len > MAX_I2C_LEN) {
+ ret = -EINVAL;
+ goto err_exit;
+ }
+ }
+
+ /* check if we can skip restart and optimize using WRRD mode */
+ if (priv->auto_restart && nmsgs == 2) {
+ if (!(msg[0].flags & I2C_M_RD) && (msg[1].flags & I2C_M_RD) &&
+ msg[0].addr == msg[1].addr) {
+ priv->auto_restart = false;
+ }
+ }
+
+ if (priv->auto_restart && nmsgs >= 2 && priv->speed > MAX_FS_MODE_SPEED)
+ /* ignore the first restart irq after the master code,
+ * otherwise the first transfer will be discarded.
+ */
+ priv->ignore_restart_irq = true;
+ else
+ priv->ignore_restart_irq = false;
+
+ while (left_num--) {
+ /* transfer slave address only to support devices detect */
+ if (!msg->buf)
+ priv->zero_len = true;
+ else
+ priv->zero_len = false;
+
+ if (msg->flags & I2C_M_RD)
+ priv->op = I2C_MASTER_RD;
+ else
+ priv->op = I2C_MASTER_WR;
+
+ if (!priv->auto_restart) {
+ if (nmsgs > 1) {
+ /* combined two messages into one transaction */
+ priv->op = I2C_MASTER_WRRD;
+ left_num--;
+ }
+ }
+ ret = mtk_i2c_do_transfer(priv, msg, nmsgs, left_num);
+ if (ret < 0)
+ goto err_exit;
+ msg++;
+ }
+ ret = 0;
+
+err_exit:
+ if (mtk_i2c_clk_disable(priv))
+ return log_msg_ret("transfer disable clk", -1);
+
+ return ret;
+}
+
+static int mtk_i2c_ofdata_to_platdata(struct udevice *dev)
+{
+ int ret;
+ struct mtk_i2c_priv *priv = dev_get_priv(dev);
+
+ priv->base = dev_remap_addr_index(dev, 0);
+ priv->pdmabase = dev_remap_addr_index(dev, 1);
+ ret = clk_get_by_index(dev, 0, &priv->clk_main);
+ if (ret)
+ return log_msg_ret("clk_get_by_index 0", ret);
+
+ ret = clk_get_by_index(dev, 1, &priv->clk_dma);
+
+ return ret;
+}
+
+static int mtk_i2c_probe(struct udevice *dev)
+{
+ struct mtk_i2c_priv *priv = dev_get_priv(dev);
+
+ priv->soc_data = (struct mtk_i2c_soc_data *)dev_get_driver_data(dev);
+ if (mtk_i2c_clk_enable(priv))
+ return log_msg_ret("probe enable clk", -1);
+ mtk_i2c_init_hw(priv);
+ if (mtk_i2c_clk_disable(priv))
+ return log_msg_ret("probe disable clk", -1);
+
+ return 0;
+}
+
+static int mtk_i2c_deblock(struct udevice *dev)
+{
+ struct mtk_i2c_priv *priv = dev_get_priv(dev);
+
+ if (mtk_i2c_clk_enable(priv))
+ return log_msg_ret("deblock enable clk", -1);
+ mtk_i2c_init_hw(priv);
+ if (mtk_i2c_clk_disable(priv))
+ return log_msg_ret("deblock disable clk", -1);
+
+ return 0;
+}
+
+static const struct mtk_i2c_soc_data mt8518_soc_data = {
+ .dma_sync = 0,
+};
+
+static const struct mtk_i2c_soc_data mt8512_soc_data = {
+ .dma_sync = 1,
+};
+
+static const struct dm_i2c_ops mtk_i2c_ops = {
+ .xfer = mtk_i2c_transfer,
+ .set_bus_speed = mtk_i2c_set_speed,
+ .deblock = mtk_i2c_deblock,
+};
+
+static const struct udevice_id mtk_i2c_ids[] = {
+ {
+ .compatible = "mediatek,mt8518-i2c",
+ .data = (ulong)&mt8518_soc_data,
+ }, {
+ .compatible = "mediatek,mt8512-i2c",
+ .data = (ulong)&mt8512_soc_data,
+ }, {
+ }
+};
+
+U_BOOT_DRIVER(mtk_i2c) = {
+ .name = "mtk_i2c",
+ .id = UCLASS_I2C,
+ .of_match = mtk_i2c_ids,
+ .ofdata_to_platdata = mtk_i2c_ofdata_to_platdata,
+ .probe = mtk_i2c_probe,
+ .priv_auto_alloc_size = sizeof(struct mtk_i2c_priv),
+ .ops = &mtk_i2c_ops,
+};
--
1.8.1.1.dirty
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