i2c-s3c2410: fix check for being in suspend.

As noted by Julia Lawall <julia@diku.dk>, we can never
trigger the check for being in suspend due to the result
of !readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN
always being 0.

Add suspend/resume hooks to stop i2c transactions happening
until the driver has been resumed.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 1fac4e233133..b7434d24904e 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -56,6 +56,7 @@ enum s3c24xx_i2c_state {
 struct s3c24xx_i2c {
         spinlock_t              lock;
         wait_queue_head_t       wait;
+        unsigned int            suspended:1;
 
         struct i2c_msg          *msg;
         unsigned int            msg_num;
@@ -507,7 +508,7 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int
         unsigned long timeout;
         int ret;
 
-        if (!(readl(i2c->regs + S3C2410_IICCON) & S3C2410_IICCON_IRQEN))
+        if (i2c->suspended)
                 return -EIO;
 
         ret = s3c24xx_i2c_set_master(i2c);
@@ -986,17 +987,26 @@ static int s3c24xx_i2c_remove(struct platform_device *pdev)
 }
 
 #ifdef CONFIG_PM
+static int s3c24xx_i2c_suspend_late(struct platform_device *dev,
+                                    pm_message_t msg)
+{
+        struct s3c24xx_i2c *i2c = platform_get_drvdata(dev);
+        i2c->suspended = 1;
+        return 0;
+}
+
 static int s3c24xx_i2c_resume(struct platform_device *dev)
 {
         struct s3c24xx_i2c *i2c = platform_get_drvdata(dev);
 
-        if (i2c != NULL)
-                s3c24xx_i2c_init(i2c);
+        i2c->suspended = 0;
+        s3c24xx_i2c_init(i2c);
 
         return 0;
 }
 
 #else
+#define s3c24xx_i2c_suspend_late NULL
 #define s3c24xx_i2c_resume NULL
 #endif
 
@@ -1005,6 +1015,7 @@ 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_late   = s3c24xx_i2c_suspend_late,
         .resume         = s3c24xx_i2c_resume,
         .driver         = {
                 .owner  = THIS_MODULE,
@@ -1015,6 +1026,7 @@ static struct platform_driver s3c2410_i2c_driver = {
 static struct platform_driver s3c2440_i2c_driver = {
         .probe          = s3c24xx_i2c_probe,
         .remove         = s3c24xx_i2c_remove,
+        .suspend_late   = s3c24xx_i2c_suspend_late,
         .resume         = s3c24xx_i2c_resume,
         .driver         = {
                 .owner  = THIS_MODULE,