UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

i2c: mxc: let time to generate stop bit 

After generating the stop bit by changing MSTA from 1 to 0,
the i2c_imx->stopped was immediatly set to 1. The second test
on i2c_imx->stopped then is correct and the controller never
waits if the bus is busy. This patch corrects this.

On mx31moboard, stop bit was not generated on single write transfers.
This was kept unnoticed as other transfers are made afterwards that
help the write recipient to resynchronize.

Thanks to Philippe and Michael for the debugging.

Signed-off-by: Valentin Longchamp <valentin.longchamp@epfl.ch>
Signed-off by: Philippe Rétornaz <philippe.retornaz@epfl.ch>
Reported-by: Michael Bonani <michael.bonani@epfl.ch>
Acked-by; Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Valentin Longchamp 2010-01-21 18:55:32 +01:00 committed by Ben Dooks
parent 92dcffb916
commit a1ee06b729
1 changed files with 3 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
drivers/i2c/busses/i2c-imx.c
View File

@ -226,7 +226,6 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
temp &= ~(I2CR_MSTA | I2CR_MTX);
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
i2c_imx->stopped = 1;
}
if (cpu_is_mx1()) {
/*
@ -236,8 +235,10 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
udelay(i2c_imx->disable_delay);
}
if (!i2c_imx->stopped)
if (!i2c_imx->stopped) {
i2c_imx_bus_busy(i2c_imx, 0);
i2c_imx->stopped = 1;
}
/* Disable I2C controller */
writeb(0, i2c_imx->base + IMX_I2C_I2CR);