On Mon, Mar 30, 2009 at 03:50:28PM +0200, Guennadi Liakhovetski wrote:
> Ok, I just was informed, that there is a hardware bug on the board I am
> using. So, please ignore my objections. Sorry for the wasted time.
Well, not completely wasted: We found a bug :) Patch follows, Ben can
you add it?
Regards,
Wolfram
===
'disable_delay' was static which is wrong as it is calculated using the per-device
bus speed. This patch turns 'disable_delay' into a per-device variable.
Reported-by: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
Signed-off-by: Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-imx.c | 7 +++----
1 file changed, 3 insertions(+), 4 deletions(-)
Index: .kernel/drivers/i2c/busses/i2c-imx.c
===================================================================
--- .kernel.orig/drivers/i2c/busses/i2c-imx.c
+++ .kernel/drivers/i2c/busses/i2c-imx.c
@@ -86,8 +86,6 @@
/** Variables ******************************************************************
*******************************************************************************/
-static unsigned int disable_delay; /* Dummy delay */
-
/*
* sorted list of clock divider, register value pairs
* taken from table 26-5, p.26-9, Freescale i.MX
@@ -121,6 +119,7 @@ struct imx_i2c_struct {
int irq;
wait_queue_head_t queue;
unsigned long i2csr;
+ unsigned int disable_delay;
};
/** Functions for IMX I2C adapter driver ***************************************
@@ -212,7 +211,7 @@ static void i2c_imx_stop(struct imx_i2c_
* This delay caused by an i.MXL hardware bug.
* If no (or too short) delay, no "STOP" bit will be generated.
*/
- udelay(disable_delay);
+ udelay(i2c_imx->disable_delay);
/* Disable I2C controller */
writeb(0, i2c_imx->base + IMX_I2C_I2CR);
}
@@ -243,7 +242,7 @@ static void __init i2c_imx_set_clk(struc
* This delay is used in I2C bus disable function
* to fix chip hardware bug.
*/
- disable_delay = (500000U * i2c_clk_div[i][0]
+ i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
+ (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
/* dev_dbg() can't be used, because adapter is not yet registered */
--
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Industrial Linux Solutions | http://www.pengutronix.de/ |
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