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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200903134704.8949-1-lars.povlsen@microchip.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/3/20 6:47 AM, Lars Povlsen wrote: > If the temperature is read before the internal calibration is > completed, the driver returns -EIO. Instead it should return -EAGAIN > to encourage repeating the operation. > > Signed-off-by: Lars Povlsen > --- > drivers/hwmon/sparx5-temp.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/hwmon/sparx5-temp.c b/drivers/hwmon/sparx5-temp.c > index 1a2b1026b026..98be48e3a22a 100644 > --- a/drivers/hwmon/sparx5-temp.c > +++ b/drivers/hwmon/sparx5-temp.c > @@ -56,7 +56,7 @@ static int s5_read(struct device *dev, enum hwmon_sensor_types type, > case hwmon_temp_input: > stat = readl_relaxed(hwmon->base + TEMP_STAT); > if (!(stat & TEMP_STAT_VALID)) > - return -EIO; > + return -EAGAIN; The problem is that this may result in a hard loop and effectively hang the system, or at least the calling process. It may be better to return -ENODATA in this situation. Guenter > value = stat & TEMP_STAT_TEMP; > /* > * From register documentation: > -- > 2.27.0 >