Patchwork [4/8] i2c: imx: wrap registers read/write to inline function

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Submitter Jingchang Lu
Date Aug. 7, 2013, 9:05 a.m.
Message ID <1375866343-2074-4-git-send-email-b35083@freescale.com>
Download mbox | patch
Permalink /patch/265453/
State Accepted
Headers show

Comments

Jingchang Lu - Aug. 7, 2013, 9:05 a.m.
wrap the readb(), writeb() into inline function calls.
It would make the driver more clearer to support platform
with different register offset.

Signed-off-by: Jingchang Lu <b35083@freescale.com>
---
 drivers/i2c/busses/i2c-imx.c | 80 +++++++++++++++++++++++++-------------------
 1 file changed, 46 insertions(+), 34 deletions(-)

Patch

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index cbea84b..1a3c608 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -160,6 +160,18 @@  static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
 	return i2c_imx->devtype == IMX1_I2C;
 }
 
+static inline void imx_i2c_write_reg(unsigned int val,
+		struct imx_i2c_struct *i2c_imx, unsigned int reg)
+{
+	writeb(val, i2c_imx->base + reg);
+}
+
+static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
+		unsigned int reg)
+{
+	return readb(i2c_imx->base + reg);
+}
+
 /** Functions for IMX I2C adapter driver ***************************************
 *******************************************************************************/
 
@@ -171,7 +183,7 @@  static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
 	dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 
 	while (1) {
-		temp = readb(i2c_imx->base + IMX_I2C_I2SR);
+		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 		if (for_busy && (temp & I2SR_IBB))
 			break;
 		if (!for_busy && !(temp & I2SR_IBB))
@@ -202,7 +214,7 @@  static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
 
 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
 {
-	if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
+	if (imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR) & I2SR_RXAK) {
 		dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
 		return -EIO;  /* No ACK */
 	}
@@ -219,25 +231,25 @@  static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
 	dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
 
 	clk_prepare_enable(i2c_imx->clk);
-	writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
+	imx_i2c_write_reg(i2c_imx->ifdr, i2c_imx, IMX_I2C_IFDR);
 	/* Enable I2C controller */
-	writeb(0, i2c_imx->base + IMX_I2C_I2SR);
-	writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
+	imx_i2c_write_reg(I2CR_IEN, i2c_imx, IMX_I2C_I2CR);
 
 	/* Wait controller to be stable */
 	udelay(50);
 
 	/* Start I2C transaction */
-	temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 	temp |= I2CR_MSTA;
-	writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 	result = i2c_imx_bus_busy(i2c_imx, 1);
 	if (result)
 		return result;
 	i2c_imx->stopped = 0;
 
 	temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
-	writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 	return result;
 }
 
@@ -248,9 +260,9 @@  static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
 	if (!i2c_imx->stopped) {
 		/* Stop I2C transaction */
 		dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
-		temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 		temp &= ~(I2CR_MSTA | I2CR_MTX);
-		writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 	}
 	if (is_imx1_i2c(i2c_imx)) {
 		/*
@@ -266,7 +278,7 @@  static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
 	}
 
 	/* Disable I2C controller */
-	writeb(0, i2c_imx->base + IMX_I2C_I2CR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
 	clk_disable_unprepare(i2c_imx->clk);
 }
 
@@ -313,12 +325,12 @@  static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
 	struct imx_i2c_struct *i2c_imx = dev_id;
 	unsigned int temp;
 
-	temp = readb(i2c_imx->base + IMX_I2C_I2SR);
+	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 	if (temp & I2SR_IIF) {
 		/* save status register */
 		i2c_imx->i2csr = temp;
 		temp &= ~I2SR_IIF;
-		writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
+		imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
 		wake_up(&i2c_imx->queue);
 		return IRQ_HANDLED;
 	}
@@ -334,7 +346,7 @@  static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 		__func__, msgs->addr << 1);
 
 	/* write slave address */
-	writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
+	imx_i2c_write_reg(msgs->addr << 1, i2c_imx, IMX_I2C_I2DR);
 	result = i2c_imx_trx_complete(i2c_imx);
 	if (result)
 		return result;
@@ -348,7 +360,7 @@  static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 		dev_dbg(&i2c_imx->adapter.dev,
 			"<%s> write byte: B%d=0x%X\n",
 			__func__, i, msgs->buf[i]);
-		writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
+		imx_i2c_write_reg(msgs->buf[i], i2c_imx, IMX_I2C_I2DR);
 		result = i2c_imx_trx_complete(i2c_imx);
 		if (result)
 			return result;
@@ -369,7 +381,7 @@  static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 		__func__, (msgs->addr << 1) | 0x01);
 
 	/* write slave address */
-	writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
+	imx_i2c_write_reg((msgs->addr << 1) | 0x01, i2c_imx, IMX_I2C_I2DR);
 	result = i2c_imx_trx_complete(i2c_imx);
 	if (result)
 		return result;
@@ -380,12 +392,12 @@  static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 	dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
 
 	/* setup bus to read data */
-	temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+	temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 	temp &= ~I2CR_MTX;
 	if (msgs->len - 1)
 		temp &= ~I2CR_TXAK;
-	writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
-	readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
+	imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
+	imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); /* dummy read */
 
 	dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
 
@@ -399,19 +411,19 @@  static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
 			   controller from generating another clock cycle */
 			dev_dbg(&i2c_imx->adapter.dev,
 				"<%s> clear MSTA\n", __func__);
-			temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+			temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 			temp &= ~(I2CR_MSTA | I2CR_MTX);
-			writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+			imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 			i2c_imx_bus_busy(i2c_imx, 0);
 			i2c_imx->stopped = 1;
 		} else if (i == (msgs->len - 2)) {
 			dev_dbg(&i2c_imx->adapter.dev,
 				"<%s> set TXAK\n", __func__);
-			temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+			temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 			temp |= I2CR_TXAK;
-			writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+			imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 		}
-		msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
+		msgs->buf[i] = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR);
 		dev_dbg(&i2c_imx->adapter.dev,
 			"<%s> read byte: B%d=0x%X\n",
 			__func__, i, msgs->buf[i]);
@@ -438,9 +450,9 @@  static int i2c_imx_xfer(struct i2c_adapter *adapter,
 		if (i) {
 			dev_dbg(&i2c_imx->adapter.dev,
 				"<%s> repeated start\n", __func__);
-			temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+			temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 			temp |= I2CR_RSTA;
-			writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
+			imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
 			result =  i2c_imx_bus_busy(i2c_imx, 1);
 			if (result)
 				goto fail0;
@@ -449,13 +461,13 @@  static int i2c_imx_xfer(struct i2c_adapter *adapter,
 			"<%s> transfer message: %d\n", __func__, i);
 		/* write/read data */
 #ifdef CONFIG_I2C_DEBUG_BUS
-		temp = readb(i2c_imx->base + IMX_I2C_I2CR);
+		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
 		dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
 			"MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
 			(temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
 			(temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
 			(temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
-		temp = readb(i2c_imx->base + IMX_I2C_I2SR);
+		temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR);
 		dev_dbg(&i2c_imx->adapter.dev,
 			"<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
 			"IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
@@ -575,8 +587,8 @@  static int __init i2c_imx_probe(struct platform_device *pdev)
 	i2c_imx_set_clk(i2c_imx, bitrate);
 
 	/* Set up chip registers to defaults */
-	writeb(0, i2c_imx->base + IMX_I2C_I2CR);
-	writeb(0, i2c_imx->base + IMX_I2C_I2SR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
 
 	/* Add I2C adapter */
 	ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
@@ -612,10 +624,10 @@  static int __exit i2c_imx_remove(struct platform_device *pdev)
 	i2c_del_adapter(&i2c_imx->adapter);
 
 	/* setup chip registers to defaults */
-	writeb(0, i2c_imx->base + IMX_I2C_IADR);
-	writeb(0, i2c_imx->base + IMX_I2C_IFDR);
-	writeb(0, i2c_imx->base + IMX_I2C_I2CR);
-	writeb(0, i2c_imx->base + IMX_I2C_I2SR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IADR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_IFDR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2CR);
+	imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
 
 	return 0;
 }