| Message ID | 20241115180717.10820-1-aardelean@baylibre.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] drivers: media: imx296: Add standby delay during probe | expand |
Hi Alexandru, Naush, Thank you for the patch. On Fri, Nov 15, 2024 at 08:07:17PM +0200, Alexandru Ardelean wrote: > From: Naushir Patuck <naush@raspberrypi.com> > > Add a 2-5ms delay when coming out of standby and before reading the > sensor info register durning probe, as instructed by the datasheet. This > standby delay is already present when the sensor starts streaming. > > During a cold-boot, reading the IMX296_SENSOR_INFO register would often > return a value of 0x0000, if this delay is not present before. > > Fixes: cb33db2b6ccfe ("media: i2c: IMX296 camera sensor driver") > Tested-by: Alexandru Ardelean <aardelean@baylibre.com> > Signed-off-by: Naushir Patuck <naush@raspberrypi.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > > Changelog v1 -> v2: > * https://lore.kernel.org/linux-media/20241115142021.574402-1-aardelean@baylibre.com/ > * Technically, this is not a true V2, but rather a new patch > - But in V1, the attempt was to fix an issue found with the upstream > IMX296 driver, which was pointed out by Kieran that it was already > fixed (more elegantly) in the RPi tree. > - The standby delay helps during a cold-boot so that the driver can read > the IMX296_SENSOR_INFO register. If the delay isn't present the value > read is 0xx0000. > - Original patch can be found: > https://github.com/raspberrypi/linux/commit/7713ce38e6a26425ace3a57b3d03ba0125c16f89 > - From the original patch of Naushir Patuck, > - Added comment > ------- > During a cold-boot, reading the IMX296_SENSOR_INFO register would often > return a value of 0x0000, if this delay is not present before. > ------- > - Added 'Tested-by: Alexandru Ardelean <aardelean@baylibre.com> > - Added 'Fixes: cb33db2b6ccfe ("media: i2c: IMX296 camera sensor driver")' > > drivers/media/i2c/imx296.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/media/i2c/imx296.c b/drivers/media/i2c/imx296.c > index f942f66fa664..395bfe4fb23d 100644 > --- a/drivers/media/i2c/imx296.c > +++ b/drivers/media/i2c/imx296.c > @@ -940,6 +940,8 @@ static int imx296_identify_model(struct imx296 *sensor) > return ret; > } > > + usleep_range(2000, 5000); > + > ret = imx296_read(sensor, IMX296_SENSOR_INFO); > if (ret < 0) { > dev_err(sensor->dev, "failed to read sensor information (%d)\n",
Quoting Alexandru Ardelean (2024-11-15 18:07:17) > From: Naushir Patuck <naush@raspberrypi.com> > > Add a 2-5ms delay when coming out of standby and before reading the > sensor info register durning probe, as instructed by the datasheet. This > standby delay is already present when the sensor starts streaming. > > During a cold-boot, reading the IMX296_SENSOR_INFO register would often > return a value of 0x0000, if this delay is not present before. > > Fixes: cb33db2b6ccfe ("media: i2c: IMX296 camera sensor driver") > Tested-by: Alexandru Ardelean <aardelean@baylibre.com> > Signed-off-by: Naushir Patuck <naush@raspberrypi.com> > --- > > Changelog v1 -> v2: > * https://lore.kernel.org/linux-media/20241115142021.574402-1-aardelean@baylibre.com/ > * Technically, this is not a true V2, but rather a new patch > - But in V1, the attempt was to fix an issue found with the upstream > IMX296 driver, which was pointed out by Kieran that it was already > fixed (more elegantly) in the RPi tree. Thanks, Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com> > - The standby delay helps during a cold-boot so that the driver can read > the IMX296_SENSOR_INFO register. If the delay isn't present the value > read is 0xx0000. > - Original patch can be found: > https://github.com/raspberrypi/linux/commit/7713ce38e6a26425ace3a57b3d03ba0125c16f89 > - From the original patch of Naushir Patuck, > - Added comment > ------- > During a cold-boot, reading the IMX296_SENSOR_INFO register would often > return a value of 0x0000, if this delay is not present before. > ------- > - Added 'Tested-by: Alexandru Ardelean <aardelean@baylibre.com> > - Added 'Fixes: cb33db2b6ccfe ("media: i2c: IMX296 camera sensor driver")' > > drivers/media/i2c/imx296.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/media/i2c/imx296.c b/drivers/media/i2c/imx296.c > index f942f66fa664..395bfe4fb23d 100644 > --- a/drivers/media/i2c/imx296.c > +++ b/drivers/media/i2c/imx296.c > @@ -940,6 +940,8 @@ static int imx296_identify_model(struct imx296 *sensor) > return ret; > } > > + usleep_range(2000, 5000); > + > ret = imx296_read(sensor, IMX296_SENSOR_INFO); > if (ret < 0) { > dev_err(sensor->dev, "failed to read sensor information (%d)\n", > -- > 2.46.1 >
diff --git a/drivers/media/i2c/imx296.c b/drivers/media/i2c/imx296.c index f942f66fa664..395bfe4fb23d 100644 --- a/drivers/media/i2c/imx296.c +++ b/drivers/media/i2c/imx296.c @@ -940,6 +940,8 @@ static int imx296_identify_model(struct imx296 *sensor) return ret; } + usleep_range(2000, 5000); + ret = imx296_read(sensor, IMX296_SENSOR_INFO); if (ret < 0) { dev_err(sensor->dev, "failed to read sensor information (%d)\n",