Patchwork [5/8] i2c: imx: change register offset representation

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Submitter Jingchang Lu
Date Aug. 7, 2013, 9:05 a.m.
Message ID <1375866343-2074-5-git-send-email-b35083@freescale.com>
Download mbox | patch
Permalink /patch/265454/
State Accepted
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Comments

Jingchang Lu - Aug. 7, 2013, 9:05 a.m.
the I2C register offset may different between SoCs,
to provid support for all these chips, split the
register offset into a fixed base address and a
variable shift value, then the full register offset
will be calculated by
reg_off = ( reg_base_addr << reg_shift)

Signed-off-by: Jingchang Lu <b35083@freescale.com>
---
 drivers/i2c/busses/i2c-imx.c | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

Patch

diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 1a3c608..8a292a9 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -64,12 +64,21 @@ 
 /* Default value */
 #define IMX_I2C_BIT_RATE	100000	/* 100kHz */
 
-/* IMX I2C registers */
+/* IMX I2C registers:
+ * the I2C register offset is different between SoCs,
+ * to provid support for all these chips, split the
+ * register offset into a fixed base address and a
+ * variable shift value, then the full register offset
+ * will be calculated by
+ * reg_off = ( reg_base_addr << reg_shift)
+ */
 #define IMX_I2C_IADR	0x00	/* i2c slave address */
-#define IMX_I2C_IFDR	0x04	/* i2c frequency divider */
-#define IMX_I2C_I2CR	0x08	/* i2c control */
-#define IMX_I2C_I2SR	0x0C	/* i2c status */
-#define IMX_I2C_I2DR	0x10	/* i2c transfer data */
+#define IMX_I2C_IFDR	0x01	/* i2c frequency divider */
+#define IMX_I2C_I2CR	0x02	/* i2c control */
+#define IMX_I2C_I2SR	0x03	/* i2c status */
+#define IMX_I2C_I2DR	0x04	/* i2c transfer data */
+
+#define IMX_I2C_REGSHIFT	2
 
 /* Bits of IMX I2C registers */
 #define I2SR_RXAK	0x01
@@ -163,13 +172,13 @@  static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
 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);
+	writeb(val, i2c_imx->base + (reg << IMX_I2C_REGSHIFT));
 }
 
 static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
 		unsigned int reg)
 {
-	return readb(i2c_imx->base + reg);
+	return readb(i2c_imx->base + (reg << IMX_I2C_REGSHIFT));
 }
 
 /** Functions for IMX I2C adapter driver ***************************************