summaryrefslogtreecommitdiffstats
path: root/drivers/i2c
diff options
context:
space:
mode:
authorJingchang Lu <b35083@freescale.com>2013-08-07 17:05:40 +0800
committerWolfram Sang <wsa@the-dreams.de>2013-08-15 16:13:17 +0200
commit8cc7331ff372b9d03f8b2eb1422052bd99430611 (patch)
tree66e705a8e5b33abd0d7d1d920a5018a9ecef926e /drivers/i2c
parent1d5ef2a83e3097408924b5eea8d7750bbde21e45 (diff)
downloadtalos-obmc-linux-8cc7331ff372b9d03f8b2eb1422052bd99430611.tar.gz
talos-obmc-linux-8cc7331ff372b9d03f8b2eb1422052bd99430611.zip
i2c: imx: change register offset representation
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> Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-imx.c23
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 1a3c60854f79..8a292a95e86a 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 ***************************************
OpenPOWER on IntegriCloud