diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-s3c2410.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-s3c2410.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index d27072b..ec3256c 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -482,7 +482,8 @@ static int s3c24xx_i2c_set_master(struct s3c24xx_i2c *i2c) static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int num) { - unsigned long timeout; + unsigned long iicstat, timeout; + int spins = 20; int ret; if (i2c->suspended) @@ -521,7 +522,21 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, /* ensure the stop has been through the bus */ - msleep(1); + dev_dbg(i2c->dev, "waiting for bus idle\n"); + + /* first, try busy waiting briefly */ + do { + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + } while ((iicstat & S3C2410_IICSTAT_START) && --spins); + + /* if that timed out sleep */ + if (!spins) { + msleep(1); + iicstat = readl(i2c->regs + S3C2410_IICSTAT); + } + + if (iicstat & S3C2410_IICSTAT_START) + dev_warn(i2c->dev, "timeout waiting for bus idle\n"); out: return ret; |