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From: Jingchang Lu <b35083-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
To: wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org
Cc: shawn.guo-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org,
	fabio.estevam-KZfg59tc24xl57MIdRCFDg@public.gmane.org,
	s.hauer-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org,
	linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org,
	Jingchang Lu <b35083-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
Subject: [PATCH 5/8] i2c: imx: change register offset representation
Date: Wed, 7 Aug 2013 17:05:40 +0800	[thread overview]
Message-ID: <1375866343-2074-5-git-send-email-b35083@freescale.com> (raw)
In-Reply-To: <1375866343-2074-1-git-send-email-b35083-KZfg59tc24xl57MIdRCFDg@public.gmane.org>

  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-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
---
 drivers/i2c/busses/i2c-imx.c | 23 ++++++++++++++++-------
 1 file changed, 16 insertions(+), 7 deletions(-)

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 ***************************************
-- 
1.8.0

  parent reply	other threads:[~2013-08-07  9:05 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-08-07  9:05 [PATCH 1/8] i2c: imx: use struct representing i2c clk{div, val} pair Jingchang Lu
     [not found] ` <1375866343-2074-1-git-send-email-b35083-KZfg59tc24xl57MIdRCFDg@public.gmane.org>
2013-08-07  9:05   ` [PATCH 2/8] i2c: imx: enable clk before write to registers Jingchang Lu
2013-08-07  9:05   ` [PATCH 3/8] i2c: imx: don't change platform device id_entry directly Jingchang Lu
2013-08-07  9:05   ` [PATCH 4/8] i2c: imx: wrap registers read/write to inline function Jingchang Lu
2013-08-07  9:05   ` Jingchang Lu [this message]
2013-08-07  9:05   ` [PATCH 6/8] i2c: imx: add INT flag and IEN bit operatation codes Jingchang Lu
2013-08-07  9:05   ` [PATCH 7/8] i2c: imx: add struct to hold more configurable quirks Jingchang Lu
2013-08-07  9:05   ` [PATCH 8/8] i2c: imx: Add Vybrid VF610 I2C controller support Jingchang Lu
2013-08-07 17:53   ` [PATCH 1/8] i2c: imx: use struct representing i2c clk{div, val} pair Sascha Hauer
     [not found]     ` <20130807175337.GQ26614-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2013-08-09  8:12       ` Lu Jingchang-B35083
2013-08-15 14:15   ` Wolfram Sang

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