linux-i2c.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] i2c: davinci: raw read and write endian fix
@ 2013-11-20 18:23 Taras Kondratiuk
       [not found] ` <1384971824-7707-1-git-send-email-taras.kondratiuk-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
  0 siblings, 1 reply; 4+ messages in thread
From: Taras Kondratiuk @ 2013-11-20 18:23 UTC (permalink / raw)
  To: Wolfram Sang
  Cc: Santosh Shilimkar, patches-QSEj5FYQhm4dnm+yROfE0A,
	linaro-networking-QSEj5FYQhm4dnm+yROfE0A,
	linaro-kernel-cunTk1MwBs8s++Sfvej+rw, Sekhar Nori, Kevin Hilman,
	davinci-linux-open-source-VycZQUHpC/PFrsHnngEfi1aTQe2KTcn/,
	linux-i2c-u79uwXL29TY76Z2rM5mHXA,
	linux-kernel-u79uwXL29TY76Z2rM5mHXA

I2C IP block 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: Taras Kondratiuk <taras.kondratiuk-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
---
Based on Linus' master tip (b4789b8).
Tested on Keystone2 EVM.

 drivers/i2c/busses/i2c-davinci.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 132369f..a629447 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -125,12 +125,12 @@ static struct davinci_i2c_platform_data davinci_i2c_platform_data_default = {
 static inline void davinci_i2c_write_reg(struct davinci_i2c_dev *i2c_dev,
 					 int reg, u16 val)
 {
-	__raw_writew(val, i2c_dev->base + reg);
+	writew_relaxed(val, i2c_dev->base + reg);
 }
 
 static inline u16 davinci_i2c_read_reg(struct davinci_i2c_dev *i2c_dev, int reg)
 {
-	return __raw_readw(i2c_dev->base + reg);
+	return readw_relaxed(i2c_dev->base + reg);
 }
 
 /* Generate a pulse on the i2c clock pin. */
-- 
1.7.9.5

^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2013-11-27 18:29 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-11-20 18:23 [PATCH] i2c: davinci: raw read and write endian fix Taras Kondratiuk
     [not found] ` <1384971824-7707-1-git-send-email-taras.kondratiuk-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
2013-11-21 17:05   ` Grygorii Strashko
2013-11-26 12:39   ` Wolfram Sang
2013-11-27 18:29   ` Wolfram Sang

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).