Jean Delvare wrote: > On Sat, 31 Jan 2009 22:10:43 +0100, Jean Delvare wrote: >> Hi Roel, >> >> On Sat, 31 Jan 2009 11:22:58 +0100, Roel Kluin wrote: >>> With a postfix decrement these timeouts reach -1 rather than 0, >>> but after the loop it is tested whether they have become 0. >>> >>> Signed-off-by: Roel Kluin <[email protected]> >>> (...) >>> diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c >>> index 6af6814..6379ec1 100644 >>> --- a/drivers/i2c/busses/i2c-pxa.c >>> +++ b/drivers/i2c/busses/i2c-pxa.c >>> @@ -644,7 +644,7 @@ static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, >>> >>> i2c_pxa_start_message(i2c); >>> >>> - while (timeout-- && i2c->msg_num > 0) { >>> + while (--timeout && i2c->msg_num > 0) { >>> i2c_pxa_handler(0, i2c); >>> udelay(10); >>> } >> Good catch. Applied, thanks for reporting. > > On second thought, shouldn't the msg_num test be done first and the > timeout test second? With the current order, you could exit with a > timeout error while all the messages were successfully transferred.
Thanks again for the review, How about: ----------------------------->8-----------------8<------------------------------ With a postfix decrement these timeouts reach -1 rather than 0, but after the loop it is tested whether they have become 0. also test before the decrement As pointed out by Jean Delvare, the msg_num should be tested before the timeout. With the current order, you could exit with a timeout error while all the messages were successfully transferred. Signed-off-by: Roel Kluin <[email protected]> --- diff --git a/drivers/i2c/busses/i2c-amd8111.c b/drivers/i2c/busses/i2c-amd8111.c index edab519..a73346b 100644 --- a/drivers/i2c/busses/i2c-amd8111.c +++ b/drivers/i2c/busses/i2c-amd8111.c @@ -72,10 +72,10 @@ static unsigned int amd_ec_wait_write(struct amd_smbus *smbus) { int timeout = 500; - while (timeout-- && (inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_IBF)) + while ((inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_IBF) && --timeout) udelay(1); - if (!timeout) { + if (timeout <= 0) { dev_warn(&smbus->dev->dev, "Timeout while waiting for IBF to clear\n"); return -ETIMEDOUT; @@ -88,10 +88,10 @@ static unsigned int amd_ec_wait_read(struct amd_smbus *smbus) { int timeout = 500; - while (timeout-- && (~inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_OBF)) + while ((~inb(smbus->base + AMD_EC_SC) & AMD_EC_SC_OBF) && --timeout) udelay(1); - if (!timeout) { + if (timeout <= 0) { dev_warn(&smbus->dev->dev, "Timeout while waiting for OBF to set\n"); return -ETIMEDOUT; diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index 6af6814..04751fa 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -644,7 +644,7 @@ static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, i2c_pxa_start_message(i2c); - while (timeout-- && i2c->msg_num > 0) { + while (i2c->msg_num > 0 && --timeout) { i2c_pxa_handler(0, i2c); udelay(10); } @@ -657,7 +657,7 @@ static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c, ret = i2c->msg_idx; out: - if (timeout == 0) + if (timeout <= 0) i2c_pxa_scream_blue_murder(i2c, "timeout"); return ret; -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
