| Message ID | 20170410134621.GA1918@mwanda (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
Hi Dan, On 04/10/2017 06:46 AM, Dan Carpenter wrote: > What we want is for regmap_read() to return zero meaning success and > for RESULT_STATUS_MASK which is BIT(31) to be set set. > > The current code is buggy in two ways. It requires both failure > conditions should be met before it fails. And if it times out then it > returns zero instead of -EIO. > > Fixes: cc96f6f6d766 ("hwmon: Support for ASPEED PWM/Fan tach") > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> > --- > Static analysis. Not tested. Thanks for the report. My fault - I had asked for this and the problem in the next patch to be fixed, I got a new version of the patch with the fix, but I did not find the time to apply it. Sorry for the noise. Guenter > > diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c > index 29010ad94208..2f22add5c73b 100644 > --- a/drivers/hwmon/aspeed-pwm-tacho.c > +++ b/drivers/hwmon/aspeed-pwm-tacho.c > @@ -512,11 +512,11 @@ static u32 aspeed_get_fan_tach_ch_rpm(struct aspeed_pwm_tacho_data *priv, > > msleep(sec); > > - while (!(regmap_read(priv->regmap, ASPEED_PTCR_RESULT, &val)) > - & !(val & RESULT_STATUS_MASK)) { > + while (regmap_read(priv->regmap, ASPEED_PTCR_RESULT, &val) || > + !(val & RESULT_STATUS_MASK)) { > timeout++; > if (timeout > 1) > - return 0; > + return -EIO; > msleep(sec); > } > > -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/hwmon/aspeed-pwm-tacho.c b/drivers/hwmon/aspeed-pwm-tacho.c index 29010ad94208..2f22add5c73b 100644 --- a/drivers/hwmon/aspeed-pwm-tacho.c +++ b/drivers/hwmon/aspeed-pwm-tacho.c @@ -512,11 +512,11 @@ static u32 aspeed_get_fan_tach_ch_rpm(struct aspeed_pwm_tacho_data *priv, msleep(sec); - while (!(regmap_read(priv->regmap, ASPEED_PTCR_RESULT, &val)) - & !(val & RESULT_STATUS_MASK)) { + while (regmap_read(priv->regmap, ASPEED_PTCR_RESULT, &val) || + !(val & RESULT_STATUS_MASK)) { timeout++; if (timeout > 1) - return 0; + return -EIO; msleep(sec); }
What we want is for regmap_read() to return zero meaning success and for RESULT_STATUS_MASK which is BIT(31) to be set set. The current code is buggy in two ways. It requires both failure conditions should be met before it fails. And if it times out then it returns zero instead of -EIO. Fixes: cc96f6f6d766 ("hwmon: Support for ASPEED PWM/Fan tach") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> --- Static analysis. Not tested. -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html