summaryrefslogtreecommitdiffstats
path: root/target/linux/s3c24xx/patches-2.6.26/1003-fix-i2c-s3c2410-resume-race.patch.patch
diff options
context:
space:
mode:
Diffstat (limited to 'target/linux/s3c24xx/patches-2.6.26/1003-fix-i2c-s3c2410-resume-race.patch.patch')
-rwxr-xr-xtarget/linux/s3c24xx/patches-2.6.26/1003-fix-i2c-s3c2410-resume-race.patch.patch106
1 files changed, 106 insertions, 0 deletions
diff --git a/target/linux/s3c24xx/patches-2.6.26/1003-fix-i2c-s3c2410-resume-race.patch.patch b/target/linux/s3c24xx/patches-2.6.26/1003-fix-i2c-s3c2410-resume-race.patch.patch
new file mode 100755
index 000000000..77e6e9c95
--- /dev/null
+++ b/target/linux/s3c24xx/patches-2.6.26/1003-fix-i2c-s3c2410-resume-race.patch.patch
@@ -0,0 +1,106 @@
+From eb5cadc7ff0e6c3aedfec3323146d7bb6bdfe0f0 Mon Sep 17 00:00:00 2001
+From: mokopatches <mokopatches@openmoko.org>
+Date: Wed, 16 Jul 2008 14:44:10 +0100
+Subject: [PATCH] fix-i2c-s3c2410-resume-race.patch
+ fix-i2c-s3c2410-resume-race.patch
+
+There is a nasty race between i2c-s3c2410 resume and resume of I2C
+driver and the client drivers -- the watchdog device actually gets to
+use the dead I2C bus before it is reinitialized by the I2C driver
+resume! This patch makes sure any customers get turned away until
+the shopkeeper has woken up.
+
+Signed-off-by: Andy Green <andy@openmoko.com>
+---
+ drivers/i2c/busses/i2c-s3c2410.c | 33 +++++++++++++++++++++++++++++++++
+ 1 files changed, 33 insertions(+), 0 deletions(-)
+
+diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
+index 9e8c875..02459d7 100644
+--- a/drivers/i2c/busses/i2c-s3c2410.c
++++ b/drivers/i2c/busses/i2c-s3c2410.c
+@@ -71,6 +71,8 @@ struct s3c24xx_i2c {
+ struct resource *irq;
+ struct resource *ioarea;
+ struct i2c_adapter adap;
++
++ int suspended;
+ };
+
+ /* default platform data to use if not supplied in the platform_device
+@@ -156,6 +158,14 @@ static inline void s3c24xx_i2c_disable_irq(struct s3c24xx_i2c *i2c)
+ unsigned long tmp;
+
+ tmp = readl(i2c->regs + S3C2410_IICCON);
++
++/* S3c2442 datasheet
++ *
++ * If the IICCON[5]=0, IICCON[4] does not operate correctly.
++ * So, It is recommended that you should set IICCON[5]=1,
++ * although you does not use the IIC interrupt.
++ */
++
+ writel(tmp & ~S3C2410_IICCON_IRQEN, i2c->regs + S3C2410_IICCON);
+ }
+
+@@ -501,6 +511,14 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int
+ unsigned long timeout;
+ int ret;
+
++ if (i2c->suspended) {
++ dev_err(i2c->dev,
++ "Hey I am still asleep (suspended: %d), retry later\n",
++ i2c->suspended);
++ ret = -EAGAIN;
++ goto out;
++ }
++
+ ret = s3c24xx_i2c_set_master(i2c);
+ if (ret != 0) {
+ dev_err(i2c->dev, "cannot get bus (error %d)\n", ret);
+@@ -885,6 +903,17 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev)
+ }
+
+ #ifdef CONFIG_PM
++
++static int s3c24xx_i2c_suspend(struct platform_device *dev, pm_message_t state)
++{
++ struct s3c24xx_i2c *i2c = platform_get_drvdata(dev);
++
++ if (i2c != NULL)
++ i2c->suspended++;
++
++ return 0;
++}
++
+ static int s3c24xx_i2c_resume(struct platform_device *dev)
+ {
+ struct s3c24xx_i2c *i2c = platform_get_drvdata(dev);
+@@ -892,6 +921,8 @@ static int s3c24xx_i2c_resume(struct platform_device *dev)
+ if (i2c != NULL)
+ s3c24xx_i2c_init(i2c);
+
++ i2c->suspended--;
++
+ return 0;
+ }
+
+@@ -904,6 +935,7 @@ static int s3c24xx_i2c_resume(struct platform_device *dev)
+ static struct platform_driver s3c2410_i2c_driver = {
+ .probe = s3c24xx_i2c_probe,
+ .remove = s3c24xx_i2c_remove,
++ .suspend = s3c24xx_i2c_suspend,
+ .resume = s3c24xx_i2c_resume,
+ .driver = {
+ .owner = THIS_MODULE,
+@@ -914,6 +946,7 @@ static struct platform_driver s3c2410_i2c_driver = {
+ static struct platform_driver s3c2440_i2c_driver = {
+ .probe = s3c24xx_i2c_probe,
+ .remove = s3c24xx_i2c_remove,
++ .suspend = s3c24xx_i2c_suspend,
+ .resume = s3c24xx_i2c_resume,
+ .driver = {
+ .owner = THIS_MODULE,
+--
+1.5.6.3
+