Patchwork [RFC,05/23] i2c: omap: raw read and write endian fix

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Submitter Taras Kondratiuk
Date Nov. 16, 2013, 12:01 a.m.
Message ID <1384560086-11994-6-git-send-email-taras.kondratiuk@linaro.org>
Download mbox | patch
Permalink /patch/291726/
State Changes Requested
Headers show

Comments

Taras Kondratiuk - Nov. 16, 2013, 12:01 a.m.
From: Victor Kamensky <victor.kamensky@linaro.org>

All OMAP IP blocks expect LE data, but CPU may operate in BE mode.
Need to use endian neutral functions to read/write h/w registers.
I.e instead of __raw_read[lw] and __raw_write[lw] functions code
need to use read[lw]_relaxed and write[lw]_relaxed functions.
If the first simply reads/writes register, the second will byteswap
it if host operates in BE mode.

Changes are trivial sed like replacement of __raw_xxx functions
with xxx_relaxed variant.

Signed-off-by: Victor Kamensky <victor.kamensky@linaro.org>
Signed-off-by: Taras Kondratiuk <taras.kondratiuk@linaro.org>
---
 drivers/i2c/busses/i2c-omap.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
Wolfram Sang - Nov. 26, 2013, 12:42 p.m.
> @@ -1142,7 +1142,7 @@ omap_i2c_probe(struct platform_device *pdev)
>  	 * Also since the omap_i2c_read_reg uses reg_map_ip_* a
>  	 * raw_readw is done.
>  	 */
> -	rev = __raw_readw(dev->base + 0x04);
> +	rev = readw_relaxed(dev->base + 0x04);
>  
>  	dev->scheme = OMAP_I2C_SCHEME(rev);
>  	switch (dev->scheme) {

Part of the comment above must be removed, too.

Patch

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 9967a6f..d69826e 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -266,13 +266,13 @@  static const u8 reg_map_ip_v2[] = {
 static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
 				      int reg, u16 val)
 {
-	__raw_writew(val, i2c_dev->base +
+	writew_relaxed(val, i2c_dev->base +
 			(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 }
 
 static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
 {
-	return __raw_readw(i2c_dev->base +
+	return readw_relaxed(i2c_dev->base +
 				(i2c_dev->regs[reg] << i2c_dev->reg_shift));
 }
 
@@ -1142,7 +1142,7 @@  omap_i2c_probe(struct platform_device *pdev)
 	 * Also since the omap_i2c_read_reg uses reg_map_ip_* a
 	 * raw_readw is done.
 	 */
-	rev = __raw_readw(dev->base + 0x04);
+	rev = readw_relaxed(dev->base + 0x04);
 
 	dev->scheme = OMAP_I2C_SCHEME(rev);
 	switch (dev->scheme) {