From: Yegor Yefremov <[email protected]> commit 6abb930af064fb1cf4177d32e2c7bfb89eee0fe5 upstream.
ret is still -1, if during the polling read_byte() returns at once with I2C_PCA_CON_SI set. So ret > 0 would lead *_waitforcompletion() to return 0, in spite of the proper behavior. The routine was rewritten, so that ret has always a proper value, before returning. Signed-off-by: Yegor Yefremov <[email protected]> Reviewed-by: Wolfram Sang <[email protected]> Signed-off-by: Jean Delvare <[email protected]> Signed-off-by: Paul Gortmaker <[email protected]> --- drivers/i2c/busses/i2c-pca-isa.c | 12 ++++++++---- drivers/i2c/busses/i2c-pca-platform.c | 11 +++++++---- 2 files changed, 15 insertions(+), 8 deletions(-) diff --git a/drivers/i2c/busses/i2c-pca-isa.c b/drivers/i2c/busses/i2c-pca-isa.c index f7346a9..62a5ce5 100644 --- a/drivers/i2c/busses/i2c-pca-isa.c +++ b/drivers/i2c/busses/i2c-pca-isa.c @@ -71,8 +71,8 @@ static int pca_isa_readbyte(void *pd, int reg) static int pca_isa_waitforcompletion(void *pd) { - long ret = ~0; unsigned long timeout; + long ret; if (irq > -1) { ret = wait_event_timeout(pca_wait, @@ -81,11 +81,15 @@ static int pca_isa_waitforcompletion(void *pd) } else { /* Do polling */ timeout = jiffies + pca_isa_ops.timeout; - while (((pca_isa_readbyte(pd, I2C_PCA_CON) - & I2C_PCA_CON_SI) == 0) - && (ret = time_before(jiffies, timeout))) + do { + ret = time_before(jiffies, timeout); + if (pca_isa_readbyte(pd, I2C_PCA_CON) + & I2C_PCA_CON_SI) + break; udelay(100); + } while (ret); } + return ret > 0; } diff --git a/drivers/i2c/busses/i2c-pca-platform.c b/drivers/i2c/busses/i2c-pca-platform.c index 5b2213d..1d8c208 100644 --- a/drivers/i2c/busses/i2c-pca-platform.c +++ b/drivers/i2c/busses/i2c-pca-platform.c @@ -80,8 +80,8 @@ static void i2c_pca_pf_writebyte32(void *pd, int reg, int val) static int i2c_pca_pf_waitforcompletion(void *pd) { struct i2c_pca_pf_data *i2c = pd; - long ret = ~0; unsigned long timeout; + long ret; if (i2c->irq) { ret = wait_event_timeout(i2c->wait, @@ -90,10 +90,13 @@ static int i2c_pca_pf_waitforcompletion(void *pd) } else { /* Do polling */ timeout = jiffies + i2c->adap.timeout; - while (((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) - & I2C_PCA_CON_SI) == 0) - && (ret = time_before(jiffies, timeout))) + do { + ret = time_before(jiffies, timeout); + if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON) + & I2C_PCA_CON_SI) + break; udelay(100); + } while (ret); } return ret > 0; -- 1.7.3.3 _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
