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Jingchang LuWolfram Sang
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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 <[email protected]> Reviewed-by: Sascha Hauer <[email protected]> Signed-off-by: Wolfram Sang <[email protected]>
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drivers/i2c/busses/i2c-imx.c

Lines changed: 16 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -64,12 +64,21 @@
6464
/* Default value */
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#define IMX_I2C_BIT_RATE 100000 /* 100kHz */
6666

67-
/* IMX I2C registers */
67+
/* IMX I2C registers:
68+
* the I2C register offset is different between SoCs,
69+
* to provid support for all these chips, split the
70+
* register offset into a fixed base address and a
71+
* variable shift value, then the full register offset
72+
* will be calculated by
73+
* reg_off = ( reg_base_addr << reg_shift)
74+
*/
6875
#define IMX_I2C_IADR 0x00 /* i2c slave address */
69-
#define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
70-
#define IMX_I2C_I2CR 0x08 /* i2c control */
71-
#define IMX_I2C_I2SR 0x0C /* i2c status */
72-
#define IMX_I2C_I2DR 0x10 /* i2c transfer data */
76+
#define IMX_I2C_IFDR 0x01 /* i2c frequency divider */
77+
#define IMX_I2C_I2CR 0x02 /* i2c control */
78+
#define IMX_I2C_I2SR 0x03 /* i2c status */
79+
#define IMX_I2C_I2DR 0x04 /* i2c transfer data */
80+
81+
#define IMX_I2C_REGSHIFT 2
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7483
/* Bits of IMX I2C registers */
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#define I2SR_RXAK 0x01
@@ -163,13 +172,13 @@ static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
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static inline void imx_i2c_write_reg(unsigned int val,
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struct imx_i2c_struct *i2c_imx, unsigned int reg)
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{
166-
writeb(val, i2c_imx->base + reg);
175+
writeb(val, i2c_imx->base + (reg << IMX_I2C_REGSHIFT));
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}
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static inline unsigned char imx_i2c_read_reg(struct imx_i2c_struct *i2c_imx,
170179
unsigned int reg)
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{
172-
return readb(i2c_imx->base + reg);
181+
return readb(i2c_imx->base + (reg << IMX_I2C_REGSHIFT));
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}
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/** Functions for IMX I2C adapter driver ***************************************

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