[U-Boot] [PATCH V3] i2c: mxc: refactor i2c driver and support dm

Peng Fan Peng.Fan at freescale.com
Mon Apr 27 15:36:00 CEST 2015


1. Introduce a new structure `struct mxc_i2c_bus`, this structure will
   used for non-DM and DM.
2. Remove `struct mxc_i2c_regs` structure, but use register offset to access
   registers based on `base` entry of `struct mxc_i2c_bus`.
3. Remove most `#ifdef I2C_QUIRK_REG`. Using driver_data to contain platform
   flags. A new flag is introduced, I2C_QUIRK_FLAG.
4. Most functions use `struct mxc_i2c_bus` as one of the parameters.
   Make most functions common to DM and non-DM, try to avoid duplicated code.
5. Support DM. Pinmux setting is still set by setup_i2c, but we do not
   need bus_i2c_init for DM.
6. struct i2c_parms and struct sram_data are removed.
7. Remove bus_i2c_read bus_i2c_write prototype in header file. The frist
   paramter of bus_i2c_init is modified to i2c index. Add new prototype
   i2c_idle_bus and force_idle_bus. Since bus_i2c_init is not good for
   DM I2C and pinctrl is missed, we use a weak function for i2c_idle_bus
   for DM part.
   Board file take the responsibility to implement this function, like this:
   "
   int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
   {
	   if (i2c_bus->index == 0)
		   force_idle_bus(i2c_pads_info0);
	   else if (i2c_bus->index == 1)
		   force_idle_bus(i2c_pads_info1);
	   else
		   xxxxxx
   }
   "

Signed-off-by: Peng Fan <Peng.Fan at freescale.com>
---

Changes v3:
 1. remove bus_i2c_init for DM, introuduce a weak function i2c_idle_bus.
 2. remove static return type for force_idle_bus, since we need to call
    it in i2c_idle_bus which may be implemented in board file. This does
    not hurt for non-DM.

Changes v2:
 1. Refactor driver, remove register access based on structure, but use
   'base + offset'
 2. Introduce mxc_i2c_bus structure
 3. Introduce I2C_QUIRK_FLAG and remove most I2C_QUIRK_REG and use
    driver_data to contain the flags for different platforms
 4. Avoid duplicated code between DM and non-DM part
 5. The function name i2c_init_transfer is not changed.
 6. Remove bus_i2c_read/write prototype from header file
 7. change bus_i2c_init's first parameter to i2c index
 8. Rename patch name, since refactor non-DM part.

 arch/arm/imx-common/i2c-mxv7.c            |   7 +-
 arch/arm/include/asm/imx-common/mxc_i2c.h |  38 +-
 drivers/i2c/mxc_i2c.c                     | 575 ++++++++++++++++++++----------
 3 files changed, 426 insertions(+), 194 deletions(-)

diff --git a/arch/arm/imx-common/i2c-mxv7.c b/arch/arm/imx-common/i2c-mxv7.c
index 1a632e7..f3a5c3f 100644
--- a/arch/arm/imx-common/i2c-mxv7.c
+++ b/arch/arm/imx-common/i2c-mxv7.c
@@ -12,7 +12,7 @@
 #include <asm/imx-common/mxc_i2c.h>
 #include <watchdog.h>
 
-static int force_idle_bus(void *priv)
+int force_idle_bus(void *priv)
 {
 	int i;
 	int sda, scl;
@@ -99,8 +99,9 @@ int setup_i2c(unsigned i2c_index, int speed, int slave_addr,
 	if (ret)
 		goto err_idle;
 
-	bus_i2c_init(i2c_bases[i2c_index], speed, slave_addr,
-			force_idle_bus, p);
+#ifndef CONFIG_DM_I2C
+	bus_i2c_init(i2c_index, speed, slave_addr, force_idle_bus, p);
+#endif
 
 	return 0;
 
diff --git a/arch/arm/include/asm/imx-common/mxc_i2c.h b/arch/arm/include/asm/imx-common/mxc_i2c.h
index af86163..355b25e 100644
--- a/arch/arm/include/asm/imx-common/mxc_i2c.h
+++ b/arch/arm/include/asm/imx-common/mxc_i2c.h
@@ -19,6 +19,36 @@ struct i2c_pads_info {
 	struct i2c_pin_ctrl sda;
 };
 
+/*
+ * Information about i2c controller
+ * struct mxc_i2c_bus - information about the i2c[x] bus
+ * @index: i2c bus index
+ * @base: Address of I2C bus controller
+ * @driver_data: Flags for different platforms, such as I2C_QUIRK_FLAG.
+ * @speed: Speed of I2C bus
+ * @pads_info: pinctrl info for this i2c bus, will be used when pinctrl is ok.
+ * The following two is only to be compatible with non-DM part.
+ * @idle_bus_fn: function to force bus idle
+ * @idle_bus_data: parameter for idle_bus_fun
+ */
+struct mxc_i2c_bus {
+	/*
+	 * board file can use this index to locate which i2c_pads_info is for
+	 * i2c_idle_bus. When pinmux is implement, this entry can be
+	 * discarded. Here we do not use dev->seq, because we do not want to
+	 * export device to board file.
+	 */
+	int index;
+	ulong base;
+	ulong driver_data;
+	int speed;
+	struct i2c_pads_info *pads_info;
+#ifndef CONFIG_DM_I2C
+	int (*idle_bus_fn)(void *p);
+	void *idle_bus_data;
+#endif
+};
+
 #if defined(CONFIG_MX6QDL)
 #define I2C_PADS(name, scl_i2c, scl_gpio, scl_gp, sda_i2c, sda_gpio, sda_gp) \
 	struct i2c_pads_info mx6q_##name = {		\
@@ -54,10 +84,8 @@ struct i2c_pads_info {
 
 int setup_i2c(unsigned i2c_index, int speed, int slave_addr,
 	      struct i2c_pads_info *p);
-void bus_i2c_init(void *base, int speed, int slave_addr,
+void bus_i2c_init(int index, int speed, int slave_addr,
 		int (*idle_bus_fn)(void *p), void *p);
-int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
-		int len);
-int bus_i2c_write(void *base, uchar chip, uint addr, int alen,
-		const uchar *buf, int len);
+int force_idle_bus(void *priv);
+int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus);
 #endif
diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c
index fc5ee35..02483b0 100644
--- a/drivers/i2c/mxc_i2c.c
+++ b/drivers/i2c/mxc_i2c.c
@@ -18,29 +18,25 @@
 #include <asm/arch/clock.h>
 #include <asm/arch/imx-regs.h>
 #include <asm/errno.h>
+#include <asm/imx-common/mxc_i2c.h>
 #include <asm/io.h>
 #include <i2c.h>
 #include <watchdog.h>
+#include <dm.h>
+#include <fdtdec.h>
 
 DECLARE_GLOBAL_DATA_PTR;
 
-#ifdef I2C_QUIRK_REG
-struct mxc_i2c_regs {
-	uint8_t		iadr;
-	uint8_t		ifdr;
-	uint8_t		i2cr;
-	uint8_t		i2sr;
-	uint8_t		i2dr;
-};
-#else
-struct mxc_i2c_regs {
-	uint32_t	iadr;
-	uint32_t	ifdr;
-	uint32_t	i2cr;
-	uint32_t	i2sr;
-	uint32_t	i2dr;
-};
-#endif
+#define I2C_QUIRK_FLAG		(1 << 0)
+
+#define IMX_I2C_REGSHIFT	2
+#define VF610_I2C_REGSHIFT	0
+/* Register index */
+#define IADR	0
+#define IFDR	1
+#define I2CR	2
+#define I2SR	3
+#define I2DR	4
 
 #define I2CR_IIEN	(1 << 6)
 #define I2CR_MSTA	(1 << 5)
@@ -104,7 +100,6 @@ static u16 i2c_clk_div[50][2] = {
 };
 #endif
 
-
 #ifndef CONFIG_SYS_MXC_I2C1_SPEED
 #define CONFIG_SYS_MXC_I2C1_SPEED 100000
 #endif
@@ -125,11 +120,10 @@ static u16 i2c_clk_div[50][2] = {
 #define CONFIG_SYS_MXC_I2C3_SLAVE 0
 #endif
 
-
 /*
  * Calculate and set proper clock divider
  */
-static uint8_t i2c_imx_get_clk(unsigned int rate)
+static uint8_t i2c_imx_get_clk(struct mxc_i2c_bus *i2c_bus, unsigned int rate)
 {
 	unsigned int i2c_clk_rate;
 	unsigned int div;
@@ -162,18 +156,20 @@ static uint8_t i2c_imx_get_clk(unsigned int rate)
 /*
  * Set I2C Bus speed
  */
-static int bus_i2c_set_bus_speed(void *base, int speed)
+static int bus_i2c_set_bus_speed(struct mxc_i2c_bus *i2c_bus, int speed)
 {
-	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
-	u8 clk_idx = i2c_imx_get_clk(speed);
+	ulong base = i2c_bus->base;
+	bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
+	u8 clk_idx = i2c_imx_get_clk(i2c_bus, speed);
 	u8 idx = i2c_clk_div[clk_idx][1];
+	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 
 	/* Store divider value */
-	writeb(idx, &i2c_regs->ifdr);
+	writeb(idx, base + (IFDR << reg_shift));
 
 	/* Reset module */
-	writeb(I2CR_IDIS, &i2c_regs->i2cr);
-	writeb(0, &i2c_regs->i2sr);
+	writeb(I2CR_IDIS, base + (I2CR << reg_shift));
+	writeb(0, base + (I2SR << reg_shift));
 	return 0;
 }
 
@@ -181,21 +177,26 @@ static int bus_i2c_set_bus_speed(void *base, int speed)
 #define ST_BUS_BUSY (I2SR_IBB | (I2SR_IBB << 8))
 #define ST_IIF (I2SR_IIF | (I2SR_IIF << 8))
 
-static int wait_for_sr_state(struct mxc_i2c_regs *i2c_regs, unsigned state)
+static int wait_for_sr_state(struct mxc_i2c_bus *i2c_bus, unsigned state)
 {
 	unsigned sr;
 	ulong elapsed;
+	bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
+	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+	ulong base = i2c_bus->base;
 	ulong start_time = get_timer(0);
 	for (;;) {
-		sr = readb(&i2c_regs->i2sr);
+		sr = readb(base + (I2SR << reg_shift));
 		if (sr & I2SR_IAL) {
-#ifdef I2C_QUIRK_REG
-			writeb(sr | I2SR_IAL, &i2c_regs->i2sr);
-#else
-			writeb(sr & ~I2SR_IAL, &i2c_regs->i2sr);
-#endif
+			if (quirk)
+				writeb(sr | I2SR_IAL, base +
+				       (I2SR << reg_shift));
+			else
+				writeb(sr & ~I2SR_IAL, base +
+				       (I2SR << reg_shift));
 			printf("%s: Arbitration lost sr=%x cr=%x state=%x\n",
-				__func__, sr, readb(&i2c_regs->i2cr), state);
+				__func__, sr, readb(base + (I2CR << reg_shift)),
+				state);
 			return -ERESTART;
 		}
 		if ((sr & (state >> 8)) == (unsigned char)state)
@@ -206,17 +207,21 @@ static int wait_for_sr_state(struct mxc_i2c_regs *i2c_regs, unsigned state)
 			break;
 	}
 	printf("%s: failed sr=%x cr=%x state=%x\n", __func__,
-			sr, readb(&i2c_regs->i2cr), state);
+	       sr, readb(base + (I2CR << reg_shift)), state);
 	return -ETIMEDOUT;
 }
 
-static int tx_byte(struct mxc_i2c_regs *i2c_regs, u8 byte)
+static int tx_byte(struct mxc_i2c_bus *i2c_bus, u8 byte)
 {
 	int ret;
+	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
+			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+	ulong base = i2c_bus->base;
 
-	writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
-	writeb(byte, &i2c_regs->i2dr);
-	ret = wait_for_sr_state(i2c_regs, ST_IIF);
+	writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
+	writeb(byte, base + (I2DR << reg_shift));
+
+	ret = wait_for_sr_state(i2c_bus, ST_IIF);
 	if (ret < 0)
 		return ret;
 	if (ret & I2SR_RX_NO_AK)
@@ -225,16 +230,28 @@ static int tx_byte(struct mxc_i2c_regs *i2c_regs, u8 byte)
 }
 
 /*
+ * Stub implementations for outer i2c slave operations.
+ */
+void __i2c_force_reset_slave(void)
+{
+}
+void i2c_force_reset_slave(void)
+	__attribute__((weak, alias("__i2c_force_reset_slave")));
+
+/*
  * Stop I2C transaction
  */
-static void i2c_imx_stop(struct mxc_i2c_regs *i2c_regs)
+static void i2c_imx_stop(struct mxc_i2c_bus *i2c_bus)
 {
 	int ret;
-	unsigned int temp = readb(&i2c_regs->i2cr);
+	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
+			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+	ulong base = i2c_bus->base;
+	unsigned int temp = readb(base + (I2CR << reg_shift));
 
 	temp &= ~(I2CR_MSTA | I2CR_MTX);
-	writeb(temp, &i2c_regs->i2cr);
-	ret = wait_for_sr_state(i2c_regs, ST_BUS_IDLE);
+	writeb(temp, base + (I2CR << reg_shift));
+	ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
 	if (ret < 0)
 		printf("%s:trigger stop failed\n", __func__);
 }
@@ -243,66 +260,96 @@ static void i2c_imx_stop(struct mxc_i2c_regs *i2c_regs)
  * Send start signal, chip address and
  * write register address
  */
-static int i2c_init_transfer_(struct mxc_i2c_regs *i2c_regs,
-		uchar chip, uint addr, int alen)
+static int i2c_init_transfer_(struct mxc_i2c_bus *i2c_bus, u8 chip,
+			      u32 addr, int alen)
 {
 	unsigned int temp;
 	int ret;
+	bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false;
+	ulong base = i2c_bus->base;
+	int reg_shift = quirk ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+
+	/* Reset i2c slave */
+	i2c_force_reset_slave();
 
 	/* Enable I2C controller */
-#ifdef I2C_QUIRK_REG
-	if (readb(&i2c_regs->i2cr) & I2CR_IDIS) {
-#else
-	if (!(readb(&i2c_regs->i2cr) & I2CR_IEN)) {
-#endif
-		writeb(I2CR_IEN, &i2c_regs->i2cr);
+	if (quirk)
+		ret = readb(base + (I2CR << reg_shift)) & I2CR_IDIS;
+	else
+		ret = !(readb(base + (I2CR << reg_shift)) & I2CR_IEN);
+
+	if (ret) {
+		writeb(I2CR_IEN, base + (I2CR << reg_shift));
 		/* Wait for controller to be stable */
 		udelay(50);
 	}
-	if (readb(&i2c_regs->iadr) == (chip << 1))
-		writeb((chip << 1) ^ 2, &i2c_regs->iadr);
-	writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
-	ret = wait_for_sr_state(i2c_regs, ST_BUS_IDLE);
+
+	if (readb(base + (IADR << reg_shift)) == (chip << 1))
+		writeb((chip << 1) ^ 2, base + (IADR << reg_shift));
+	writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
+	ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE);
 	if (ret < 0)
 		return ret;
 
 	/* Start I2C transaction */
-	temp = readb(&i2c_regs->i2cr);
+	temp = readb(base + (I2CR << reg_shift));
 	temp |= I2CR_MSTA;
-	writeb(temp, &i2c_regs->i2cr);
+	writeb(temp, base + (I2CR << reg_shift));
 
-	ret = wait_for_sr_state(i2c_regs, ST_BUS_BUSY);
+	ret = wait_for_sr_state(i2c_bus, ST_BUS_BUSY);
 	if (ret < 0)
 		return ret;
 
 	temp |= I2CR_MTX | I2CR_TX_NO_AK;
-	writeb(temp, &i2c_regs->i2cr);
+	writeb(temp, base + (I2CR << reg_shift));
 
 	/* write slave address */
-	ret = tx_byte(i2c_regs, chip << 1);
+	ret = tx_byte(i2c_bus, chip << 1);
 	if (ret < 0)
 		return ret;
 
 	while (alen--) {
-		ret = tx_byte(i2c_regs, (addr >> (alen * 8)) & 0xff);
+		ret = tx_byte(i2c_bus, (addr >> (alen * 8)) & 0xff);
 		if (ret < 0)
 			return ret;
 	}
 	return 0;
 }
 
-static int i2c_idle_bus(void *base);
+#ifndef CONFIG_DM_I2C
+int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
+{
+	if (i2c_bus && i2c_bus->idle_bus_fn)
+		return i2c_bus->idle_bus_fn(i2c_bus->idle_bus_data);
+	return 0;
+}
+#else
+/*
+ * Since pinmux is not supported, implement a weak function here.
+ * You can implement your i2c_bus_idle in board file. When pinctrl
+ * is supported, this can be removed.
+ */
+int __i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
+{
+	return 0;
+}
+
+int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
+	__attribute__((weak, alias("__i2c_idle_bus")));
+#endif
 
-static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
-		uchar chip, uint addr, int alen)
+static int i2c_init_transfer(struct mxc_i2c_bus *i2c_bus, u8 chip,
+			     u32 addr, int alen)
 {
 	int retry;
 	int ret;
+	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
+			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
 	for (retry = 0; retry < 3; retry++) {
-		ret = i2c_init_transfer_(i2c_regs, chip, addr, alen);
+		ret = i2c_init_transfer_(i2c_bus, chip, addr, alen);
 		if (ret >= 0)
 			return 0;
-		i2c_imx_stop(i2c_regs);
+		i2c_imx_stop(i2c_bus);
 		if (ret == -ENODEV)
 			return ret;
 
@@ -310,54 +357,67 @@ static int i2c_init_transfer(struct mxc_i2c_regs *i2c_regs,
 				retry);
 		if (ret != -ERESTART)
 			/* Disable controller */
-			writeb(I2CR_IDIS, &i2c_regs->i2cr);
+			writeb(I2CR_IDIS, i2c_bus->base + (I2CR << reg_shift));
 		udelay(100);
-		if (i2c_idle_bus(i2c_regs) < 0)
+		if (i2c_idle_bus(i2c_bus) < 0)
 			break;
 	}
-	printf("%s: give up i2c_regs=%p\n", __func__, i2c_regs);
+	printf("%s: give up i2c_regs=0x%lx\n", __func__, i2c_bus->base);
 	return ret;
 }
 
-/*
- * Read data from I2C device
- */
-int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
-		int len)
+
+static int i2c_write_data(struct mxc_i2c_bus *i2c_bus, u8 chip, const u8 *buf,
+			  int len)
+{
+	int i, ret = 0;
+
+	debug("i2c_write_data: chip=0x%x, len=0x%x\n", chip, len);
+	debug("write_data: ");
+	/* use rc for counter */
+	for (i = 0; i < len; ++i)
+		debug(" 0x%02x", buf[i]);
+	debug("\n");
+
+	for (i = 0; i < len; i++) {
+		ret = tx_byte(i2c_bus, buf[i]);
+		if (ret < 0) {
+			debug("i2c_write_data(): rc=%d\n", ret);
+			break;
+		}
+	}
+
+	return ret;
+}
+
+static int i2c_read_data(struct mxc_i2c_bus *i2c_bus, uchar chip, uchar *buf,
+			 int len)
 {
 	int ret;
 	unsigned int temp;
 	int i;
-	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
+	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
+			VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+	ulong base = i2c_bus->base;
 
-	ret = i2c_init_transfer(i2c_regs, chip, addr, alen);
-	if (ret < 0)
-		return ret;
-
-	temp = readb(&i2c_regs->i2cr);
-	temp |= I2CR_RSTA;
-	writeb(temp, &i2c_regs->i2cr);
-
-	ret = tx_byte(i2c_regs, (chip << 1) | 1);
-	if (ret < 0) {
-		i2c_imx_stop(i2c_regs);
-		return ret;
-	}
+	debug("i2c_read_data: chip=0x%x, len=0x%x\n", chip, len);
 
 	/* setup bus to read data */
-	temp = readb(&i2c_regs->i2cr);
+	temp = readb(base + (I2CR << reg_shift));
 	temp &= ~(I2CR_MTX | I2CR_TX_NO_AK);
 	if (len == 1)
 		temp |= I2CR_TX_NO_AK;
-	writeb(temp, &i2c_regs->i2cr);
-	writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
-	readb(&i2c_regs->i2dr);		/* dummy read to clear ICF */
+	writeb(temp, base + (I2CR << reg_shift));
+	writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
+	/* dummy read to clear ICF */
+	readb(base + (I2DR << reg_shift));
 
 	/* read data */
 	for (i = 0; i < len; i++) {
-		ret = wait_for_sr_state(i2c_regs, ST_IIF);
+		ret = wait_for_sr_state(i2c_bus, ST_IIF);
 		if (ret < 0) {
-			i2c_imx_stop(i2c_regs);
+			debug("i2c_read_data(): ret=%d\n", ret);
+			i2c_imx_stop(i2c_bus);
 			return ret;
 		}
 
@@ -366,105 +426,111 @@ int bus_i2c_read(void *base, uchar chip, uint addr, int alen, uchar *buf,
 		 * controller from generating another clock cycle
 		 */
 		if (i == (len - 1)) {
-			i2c_imx_stop(i2c_regs);
+			i2c_imx_stop(i2c_bus);
 		} else if (i == (len - 2)) {
-			temp = readb(&i2c_regs->i2cr);
+			temp = readb(base + (I2CR << reg_shift));
 			temp |= I2CR_TX_NO_AK;
-			writeb(temp, &i2c_regs->i2cr);
+			writeb(temp, base + (I2CR << reg_shift));
 		}
-		writeb(I2SR_IIF_CLEAR, &i2c_regs->i2sr);
-		buf[i] = readb(&i2c_regs->i2dr);
+		writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift));
+		buf[i] = readb(base + (I2DR << reg_shift));
 	}
-	i2c_imx_stop(i2c_regs);
+
+	/* reuse ret for counter*/
+	for (ret = 0; ret < len; ++ret)
+		debug(" 0x%02x", buf[ret]);
+	debug("\n");
+
+	i2c_imx_stop(i2c_bus);
 	return 0;
 }
 
+#ifndef CONFIG_DM_I2C
 /*
- * Write data to I2C device
+ * Read data from I2C device
  */
-int bus_i2c_write(void *base, uchar chip, uint addr, int alen,
-		const uchar *buf, int len)
+static int bus_i2c_read(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
+			int alen, u8 *buf, int len)
 {
-	int ret;
-	int i;
-	struct mxc_i2c_regs *i2c_regs = (struct mxc_i2c_regs *)base;
+	int ret = 0;
+	u32 temp;
+	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
+		VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+	ulong base = i2c_bus->base;
 
-	ret = i2c_init_transfer(i2c_regs, chip, addr, alen);
+	ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
 	if (ret < 0)
 		return ret;
 
-	for (i = 0; i < len; i++) {
-		ret = tx_byte(i2c_regs, buf[i]);
-		if (ret < 0)
-			break;
+	temp = readb(base + (I2CR << reg_shift));
+	temp |= I2CR_RSTA;
+	writeb(temp, base + (I2CR << reg_shift));
+
+	ret = tx_byte(i2c_bus, (chip << 1) | 1);
+	if (ret < 0) {
+		i2c_imx_stop(i2c_bus);
+		return ret;
 	}
-	i2c_imx_stop(i2c_regs);
+
+	ret = i2c_read_data(i2c_bus, chip, buf, len);
+
+	i2c_imx_stop(i2c_bus);
+	return ret;
+}
+
+/*
+ * Write data to I2C device
+ */
+static int bus_i2c_write(struct mxc_i2c_bus *i2c_bus, u8 chip, u32 addr,
+			 int alen, const u8 *buf, int len)
+{
+	int ret = 0;
+
+	ret = i2c_init_transfer(i2c_bus, chip, addr, alen);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_write_data(i2c_bus, chip, buf, len);
+
+	i2c_imx_stop(i2c_bus);
+
 	return ret;
 }
 
-static void * const i2c_bases[] = {
+static struct mxc_i2c_bus mxc_i2c_buses[] = {
 #if defined(CONFIG_MX25)
-	(void *)IMX_I2C_BASE,
-	(void *)IMX_I2C2_BASE,
-	(void *)IMX_I2C3_BASE
+	{ 0, IMX_I2C_BASE },
+	{ 1, IMX_I2C2_BASE },
+	{ 2, IMX_I2C3_BASE },
 #elif defined(CONFIG_MX27)
-	(void *)IMX_I2C1_BASE,
-	(void *)IMX_I2C2_BASE
+	{ 0, IMX_I2C1_BASE },
+	{ 1, IMX_I2C2_BASE },
 #elif defined(CONFIG_MX31) || defined(CONFIG_MX35) || \
 	defined(CONFIG_MX51) || defined(CONFIG_MX53) ||	\
-	defined(CONFIG_MX6) || defined(CONFIG_LS102XA)
-	(void *)I2C1_BASE_ADDR,
-	(void *)I2C2_BASE_ADDR,
-	(void *)I2C3_BASE_ADDR
-#elif defined(CONFIG_VF610)
-	(void *)I2C0_BASE_ADDR
+	defined(CONFIG_MX6)
+	{ 0, I2C1_BASE_ADDR },
+	{ 1, I2C2_BASE_ADDR },
+	{ 2, I2C3_BASE_ADDR },
+#elif defined(CONFIG_LS102XA)
+	{ 0, I2C1_BASE_ADDR, I2C_QUIRK_FLAG },
+	{ 1, I2C2_BASE_ADDR, I2C_QUIRK_FLAG },
+	{ 2, I2C3_BASE_ADDR, I2C_QUIRK_FLAG },
+#elif def ined(CONFIG_VF610)
+	{ 0, I2C0_BASE_ADDR, I2C_QUIRK_FLAG },
 #elif defined(CONFIG_FSL_LSCH3)
-	(void *)I2C1_BASE_ADDR,
-	(void *)I2C2_BASE_ADDR,
-	(void *)I2C3_BASE_ADDR,
-	(void *)I2C4_BASE_ADDR
+	{ 0, I2C1_BASE_ADDR, I2C_QUIRK_FLAG },
+	{ 1, I2C2_BASE_ADDR, I2C_QUIRK_FLAG },
+	{ 2, I2C3_BASE_ADDR, I2C_QUIRK_FLAG },
+	{ 3, I2C4_BASE_ADDR, I2C_QUIRK_FLAG },
 #else
 #error "architecture not supported"
 #endif
+	{ }
 };
 
-struct i2c_parms {
-	void *base;
-	void *idle_bus_data;
-	int (*idle_bus_fn)(void *p);
-};
-
-struct sram_data {
-	unsigned curr_i2c_bus;
-	struct i2c_parms i2c_data[ARRAY_SIZE(i2c_bases)];
-};
-
-void *i2c_get_base(struct i2c_adapter *adap)
+struct mxc_i2c_bus *i2c_get_base(struct i2c_adapter *adap)
 {
-	return i2c_bases[adap->hwadapnr];
-}
-
-static struct i2c_parms *i2c_get_parms(void *base)
-{
-	struct sram_data *srdata = (void *)gd->srdata;
-	int i = 0;
-	struct i2c_parms *p = srdata->i2c_data;
-	while (i < ARRAY_SIZE(srdata->i2c_data)) {
-		if (p->base == base)
-			return p;
-		p++;
-		i++;
-	}
-	printf("Invalid I2C base: %p\n", base);
-	return NULL;
-}
-
-static int i2c_idle_bus(void *base)
-{
-	struct i2c_parms *p = i2c_get_parms(base);
-	if (p && p->idle_bus_fn)
-		return p->idle_bus_fn(p->idle_bus_data);
-	return 0;
+	return &mxc_i2c_buses[adap->hwadapnr];
 }
 
 static int mxc_i2c_read(struct i2c_adapter *adap, uint8_t chip,
@@ -489,29 +555,26 @@ static int mxc_i2c_probe(struct i2c_adapter *adap, uint8_t chip)
 	return bus_i2c_write(i2c_get_base(adap), chip, 0, 0, NULL, 0);
 }
 
-void bus_i2c_init(void *base, int speed, int unused,
-		int (*idle_bus_fn)(void *p), void *idle_bus_data)
+void bus_i2c_init(int index, int speed, int unused,
+		  int (*idle_bus_fn)(void *p), void *idle_bus_data)
 {
-	struct sram_data *srdata = (void *)gd->srdata;
-	int i = 0;
-	struct i2c_parms *p = srdata->i2c_data;
-	if (!base)
+	int ret;
+
+	if (index >= ARRAY_SIZE(mxc_i2c_buses)) {
+		debug("Error i2c index\n");
 		return;
-	for (;;) {
-		if (!p->base || (p->base == base)) {
-			p->base = base;
-			if (idle_bus_fn) {
-				p->idle_bus_fn = idle_bus_fn;
-				p->idle_bus_data = idle_bus_data;
-			}
-			break;
-		}
-		p++;
-		i++;
-		if (i >= ARRAY_SIZE(srdata->i2c_data))
-			return;
 	}
-	bus_i2c_set_bus_speed(base, speed);
+
+	mxc_i2c_buses[index].idle_bus_fn = idle_bus_fn;
+	mxc_i2c_buses[index].idle_bus_data = idle_bus_data;
+
+	ret = enable_i2c_clk(1, index);
+	if (ret < 0) {
+		debug("I2C-%d clk fail to enable.\n", index);
+		return ret
+	}
+
+	bus_i2c_set_bus_speed(&mxc_i2c_buses[index], speed);
 }
 
 /*
@@ -519,13 +582,13 @@ void bus_i2c_init(void *base, int speed, int unused,
  */
 static void mxc_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
 {
-	bus_i2c_init(i2c_get_base(adap), speed, slaveaddr, NULL, NULL);
+	bus_i2c_init(adap->hwadapnr, speed, slaveaddr, NULL, NULL);
 }
 
 /*
  * Set I2C Speed
  */
-static uint mxc_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed)
+static u32 mxc_i2c_set_bus_speed(struct i2c_adapter *adap, uint speed)
 {
 	return bus_i2c_set_bus_speed(i2c_get_base(adap), speed);
 }
@@ -552,3 +615,143 @@ U_BOOT_I2C_ADAP_COMPLETE(mxc2, mxc_i2c_init, mxc_i2c_probe,
 			 CONFIG_SYS_MXC_I2C3_SPEED,
 			 CONFIG_SYS_MXC_I2C3_SLAVE, 2)
 #endif
+
+#else
+
+static int mxc_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
+{
+	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
+
+	return bus_i2c_set_bus_speed(i2c_bus, speed);
+}
+
+static int mxc_i2c_probe(struct udevice *bus)
+{
+	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
+	fdt_addr_t addr;
+	int ret;
+
+	i2c_bus->driver_data = dev_get_driver_data(bus);
+
+	addr = dev_get_addr(bus);
+	if (addr == FDT_ADDR_T_NONE)
+		return -ENODEV;
+
+	i2c_bus->base = addr;
+	i2c_bus->index = bus->seq;
+
+	/* Enable clk */
+	ret = enable_i2c_clk(1, bus->seq);
+	if (ret < 0)
+		return ret;
+
+	ret = i2c_idle_bus(i2c_bus);
+	if (ret < 0) {
+		/* Disable clk */
+		enable_i2c_clk(0, bus->seq);
+		return ret;
+	}
+
+	/*
+	 * Pinmux settings are in board file now, until pinmux is supported,
+	 * we can set pinmux here in probe function.
+	 */
+
+	debug("i2c : controller bus %d at %lu , speed %d: ",
+	      bus->seq, i2c_bus->base,
+	      i2c_bus->speed);
+
+	return 0;
+}
+
+static int mxc_i2c_probe_chip(struct udevice *bus, u32 chip_addr,
+			      u32 chip_flags)
+{
+	int ret;
+	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
+
+	ret = i2c_init_transfer(i2c_bus, chip_addr, 0, 0);
+	if (ret < 0) {
+		debug("%s failed, ret = %d\n", __func__, ret);
+		return ret;
+	}
+
+	i2c_imx_stop(i2c_bus);
+
+	return 0;
+}
+
+static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
+{
+	struct mxc_i2c_bus *i2c_bus = dev_get_priv(bus);
+	int ret = 0;
+	ulong base = i2c_bus->base;
+	int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ?
+		VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT;
+
+	/*
+	 * Here the 3rd parameter addr and the 4th one alen are set to 0,
+	 * because here we only want to send out chip address. The register
+	 * address is wrapped in msg.
+	 */
+	ret = i2c_init_transfer(i2c_bus, msg->addr, 0, 0);
+	if (ret < 0) {
+		debug("i2c_init_transfer error: %d\n", ret);
+		return ret;
+	}
+
+	for (; nmsgs > 0; nmsgs--, msg++) {
+		bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
+		debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
+		if (msg->flags & I2C_M_RD)
+			ret = i2c_read_data(i2c_bus, msg->addr, msg->buf,
+					    msg->len);
+		else {
+			ret = i2c_write_data(i2c_bus, msg->addr, msg->buf,
+					     msg->len);
+			if (ret)
+				break;
+			if (next_is_read) {
+				/* Reuse ret */
+				ret = readb(base + (I2CR << reg_shift));
+				ret |= I2CR_RSTA;
+				writeb(ret, base + (I2CR << reg_shift));
+
+				ret = tx_byte(i2c_bus, (msg->addr << 1) | 1);
+				if (ret < 0) {
+					i2c_imx_stop(i2c_bus);
+					break;
+				}
+			}
+		}
+	}
+
+	if (ret)
+		debug("i2c_write: error sending\n");
+
+	i2c_imx_stop(i2c_bus);
+
+	return ret;
+}
+
+static const struct dm_i2c_ops mxc_i2c_ops = {
+	.xfer		= mxc_i2c_xfer,
+	.probe_chip	= mxc_i2c_probe_chip,
+	.set_bus_speed	= mxc_i2c_set_bus_speed,
+};
+
+static const struct udevice_id mxc_i2c_ids[] = {
+	{ .compatible = "fsl,imx21-i2c", },
+	{ .compatible = "fsl,vf610-i2c", .data = I2C_QUIRK_FLAG, },
+	{}
+};
+
+U_BOOT_DRIVER(i2c_mxc) = {
+	.name = "i2c_mxc",
+	.id = UCLASS_I2C,
+	.of_match = mxc_i2c_ids,
+	.probe = mxc_i2c_probe,
+	.priv_auto_alloc_size = sizeof(struct mxc_i2c_bus),
+	.ops = &mxc_i2c_ops,
+};
+#endif
-- 
1.8.4




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