drivers/media/i2c/ov5640.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-)
From: Jason Yang <jason98166@gmail.com>
ov5640_set_stream_mipi() always programs IO_MIPI_CTRL00 with 0x45,
which selects the two data lane mode: the number of data lanes
described in the devicetree endpoint only feeds the sensor's clock
tree computations, so a module wired with one data lane starts
streaming in two lane mode and the receiver never assembles a
frame.
Take the lane mode from the endpoint instead. The field encodes
the lane count directly - 001 for one lane, 010 for two - per the
current sensor manual (version 2.33). The 2.03 manual documented
000/001 for one/two lanes; OmniVision corrected the table in
version 2.1, which is why the long-standing comment here found 001
unusable for two lanes and validated 010 instead.
The power-up path also programs a two data lane mode, but that
value is overwritten when streaming starts, so it is left alone.
Tested with a single data lane module on an i.MX8MP board
(imx-mipi-csis receiver), where the unpatched value produces no
frames at all, and on an RK3588 board.
Fixes: 19a81c1426c1 ("[media] add Omnivision OV5640 sensor driver")
Cc: stable@vger.kernel.org
Signed-off-by: Jason Yang <jason98166@gmail.com>
Assisted-by: Claude:claude-opus-5
---
Changes in v3:
- Inline the lane count in the write instead of going through a
local variable (Sakari Ailus).
- Link to v2: https://lore.kernel.org/r/20260811-ov5640-1lane-v1-v2-1-65205ae86feb@gmail.com
Changes in v2:
- Compute the register value from the lane count in the single
write instead of branching on it (Sakari Ailus), with the count
in a local variable to stay within 80 columns; the programmed
values are unchanged, 0x25 for one lane and 0x45 for two.
- Request a normal stable backport rather than opting out of
AUTOSEL (Sakari Ailus).
- Drop the quotes around the function name in the reference from
ov5640_set_power_mipi() (Sakari Ailus).
- Link to v1: https://lore.kernel.org/r/20260811-ov5640-1lane-v1-v1-1-79699457ce13@gmail.com
---
drivers/media/i2c/ov5640.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)
diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
index 8deb5f5501fa..18c3bb5498f8 100644
--- a/drivers/media/i2c/ov5640.c
+++ b/drivers/media/i2c/ov5640.c
@@ -1831,22 +1831,16 @@ static int ov5640_set_stream_mipi(struct ov5640_dev *sensor, bool on)
/*
* Enable/disable the MIPI interface
*
- * 0x300e = on ? 0x45 : 0x40
- *
- * FIXME: the sensor manual (version 2.03) reports
- * [7:5] = 000 : 1 data lane mode
- * [7:5] = 001 : 2 data lanes mode
- * But this settings do not work, while the following ones
- * have been validated for 2 data lanes mode.
- *
- * [7:5] = 010 : 2 data lanes mode
+ * [7:5] : data lane count, 001 for one lane and 010 for two,
+ * per version 2.33 of the sensor manual
* [4] = 0 : Power up MIPI HS Tx
* [3] = 0 : Power up MIPI LS Rx
* [2] = 1/0 : MIPI interface enable/disable
* [1:0] = 01/00: FIXME: 'debug'
*/
ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00,
- on ? 0x45 : 0x40);
+ on ? 0x5 | sensor->ep.bus.mipi_csi2.num_data_lanes << 5 :
+ 0x40);
if (ret)
return ret;
@@ -2535,8 +2529,8 @@ static int ov5640_set_power_mipi(struct ov5640_dev *sensor, bool on)
* Power up MIPI HS Tx and LS Rx; 2 data lanes mode
*
* 0x300e = 0x40
- * [7:5] = 010 : 2 data lanes mode (see FIXME note in
- * "ov5640_set_stream_mipi()")
+ * [7:5] = 010 : 2 data lanes mode (see the note in
+ * ov5640_set_stream_mipi())
* [4] = 0 : Power up MIPI HS Tx
* [3] = 0 : Power up MIPI LS Rx
* [2] = 1 : MIPI interface enabled
---
base-commit: 1590cf0329716306e948a8fc29f1d3ee87d3989f
change-id: 20260811-ov5640-1lane-v1-b0fe37eab4d8
Best regards,
--
Jason Yang <jason98166@gmail.com>Hi,
On 11-Aug-26 09:30, Jason Yang via B4 Relay wrote:
> From: Jason Yang <jason98166@gmail.com>
>
> ov5640_set_stream_mipi() always programs IO_MIPI_CTRL00 with 0x45,
> which selects the two data lane mode: the number of data lanes
> described in the devicetree endpoint only feeds the sensor's clock
> tree computations, so a module wired with one data lane starts
> streaming in two lane mode and the receiver never assembles a
> frame.
>
> Take the lane mode from the endpoint instead. The field encodes
> the lane count directly - 001 for one lane, 010 for two - per the
> current sensor manual (version 2.33). The 2.03 manual documented
> 000/001 for one/two lanes; OmniVision corrected the table in
> version 2.1, which is why the long-standing comment here found 001
> unusable for two lanes and validated 010 instead.
>
> The power-up path also programs a two data lane mode, but that
> value is overwritten when streaming starts, so it is left alone.
>
> Tested with a single data lane module on an i.MX8MP board
> (imx-mipi-csis receiver), where the unpatched value produces no
> frames at all, and on an RK3588 board.
>
> Fixes: 19a81c1426c1 ("[media] add Omnivision OV5640 sensor driver")
> Cc: stable@vger.kernel.org
> Signed-off-by: Jason Yang <jason98166@gmail.com>
> Assisted-by: Claude:claude-opus-5
> ---
> Changes in v3:
> - Inline the lane count in the write instead of going through a
> local variable (Sakari Ailus).
> - Link to v2: https://lore.kernel.org/r/20260811-ov5640-1lane-v1-v2-1-65205ae86feb@gmail.com
>
> Changes in v2:
> - Compute the register value from the lane count in the single
> write instead of branching on it (Sakari Ailus), with the count
> in a local variable to stay within 80 columns; the programmed
> values are unchanged, 0x25 for one lane and 0x45 for two.
> - Request a normal stable backport rather than opting out of
> AUTOSEL (Sakari Ailus).
> - Drop the quotes around the function name in the reference from
> ov5640_set_power_mipi() (Sakari Ailus).
> - Link to v1: https://lore.kernel.org/r/20260811-ov5640-1lane-v1-v1-1-79699457ce13@gmail.com
> ---
> drivers/media/i2c/ov5640.c | 18 ++++++------------
> 1 file changed, 6 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> index 8deb5f5501fa..18c3bb5498f8 100644
> --- a/drivers/media/i2c/ov5640.c
> +++ b/drivers/media/i2c/ov5640.c
> @@ -1831,22 +1831,16 @@ static int ov5640_set_stream_mipi(struct ov5640_dev *sensor, bool on)
> /*
> * Enable/disable the MIPI interface
> *
> - * 0x300e = on ? 0x45 : 0x40
> - *
> - * FIXME: the sensor manual (version 2.03) reports
> - * [7:5] = 000 : 1 data lane mode
> - * [7:5] = 001 : 2 data lanes mode
> - * But this settings do not work, while the following ones
> - * have been validated for 2 data lanes mode.
> - *
> - * [7:5] = 010 : 2 data lanes mode
> + * [7:5] : data lane count, 001 for one lane and 010 for two,
> + * per version 2.33 of the sensor manual
> * [4] = 0 : Power up MIPI HS Tx
> * [3] = 0 : Power up MIPI LS Rx
> * [2] = 1/0 : MIPI interface enable/disable
> * [1:0] = 01/00: FIXME: 'debug'
> */
> ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00,
> - on ? 0x45 : 0x40);
> + on ? 0x5 | sensor->ep.bus.mipi_csi2.num_data_lanes << 5 :
> + 0x40);
You're writing 0x40 aka 2 lines now when turning the sensor off in 1 line mode.
I believe this should be:
ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00,
sensor->ep.bus.mipi_csi2.num_data_lanes << 5 |
(on ? 0x05 : 0x0));
Only changing the low nibble for on / off and always setting the correct
lane count.
Regards,
Hans
Hi Hans,
Thanks for the review.
> Only changing the low nibble for on / off and always setting the correct
> lane count.
You're right, that is more consistent - applied exactly as you
wrote it in v4.
Regards,
Jason
<johannes.goede@oss.qualcomm.com> 於 2026年8月11日週二 下午4:57寫道：
>
> Hi,
>
> On 11-Aug-26 09:30, Jason Yang via B4 Relay wrote:
> > From: Jason Yang <jason98166@gmail.com>
> >
> > ov5640_set_stream_mipi() always programs IO_MIPI_CTRL00 with 0x45,
> > which selects the two data lane mode: the number of data lanes
> > described in the devicetree endpoint only feeds the sensor's clock
> > tree computations, so a module wired with one data lane starts
> > streaming in two lane mode and the receiver never assembles a
> > frame.
> >
> > Take the lane mode from the endpoint instead. The field encodes
> > the lane count directly - 001 for one lane, 010 for two - per the
> > current sensor manual (version 2.33). The 2.03 manual documented
> > 000/001 for one/two lanes; OmniVision corrected the table in
> > version 2.1, which is why the long-standing comment here found 001
> > unusable for two lanes and validated 010 instead.
> >
> > The power-up path also programs a two data lane mode, but that
> > value is overwritten when streaming starts, so it is left alone.
> >
> > Tested with a single data lane module on an i.MX8MP board
> > (imx-mipi-csis receiver), where the unpatched value produces no
> > frames at all, and on an RK3588 board.
> >
> > Fixes: 19a81c1426c1 ("[media] add Omnivision OV5640 sensor driver")
> > Cc: stable@vger.kernel.org
> > Signed-off-by: Jason Yang <jason98166@gmail.com>
> > Assisted-by: Claude:claude-opus-5
> > ---
> > Changes in v3:
> > - Inline the lane count in the write instead of going through a
> > local variable (Sakari Ailus).
> > - Link to v2: https://lore.kernel.org/r/20260811-ov5640-1lane-v1-v2-1-65205ae86feb@gmail.com
> >
> > Changes in v2:
> > - Compute the register value from the lane count in the single
> > write instead of branching on it (Sakari Ailus), with the count
> > in a local variable to stay within 80 columns; the programmed
> > values are unchanged, 0x25 for one lane and 0x45 for two.
> > - Request a normal stable backport rather than opting out of
> > AUTOSEL (Sakari Ailus).
> > - Drop the quotes around the function name in the reference from
> > ov5640_set_power_mipi() (Sakari Ailus).
> > - Link to v1: https://lore.kernel.org/r/20260811-ov5640-1lane-v1-v1-1-79699457ce13@gmail.com
> > ---
> > drivers/media/i2c/ov5640.c | 18 ++++++------------
> > 1 file changed, 6 insertions(+), 12 deletions(-)
> >
> > diff --git a/drivers/media/i2c/ov5640.c b/drivers/media/i2c/ov5640.c
> > index 8deb5f5501fa..18c3bb5498f8 100644
> > --- a/drivers/media/i2c/ov5640.c
> > +++ b/drivers/media/i2c/ov5640.c
> > @@ -1831,22 +1831,16 @@ static int ov5640_set_stream_mipi(struct ov5640_dev *sensor, bool on)
> > /*
> > * Enable/disable the MIPI interface
> > *
> > - * 0x300e = on ? 0x45 : 0x40
> > - *
> > - * FIXME: the sensor manual (version 2.03) reports
> > - * [7:5] = 000 : 1 data lane mode
> > - * [7:5] = 001 : 2 data lanes mode
> > - * But this settings do not work, while the following ones
> > - * have been validated for 2 data lanes mode.
> > - *
> > - * [7:5] = 010 : 2 data lanes mode
> > + * [7:5] : data lane count, 001 for one lane and 010 for two,
> > + * per version 2.33 of the sensor manual
> > * [4] = 0 : Power up MIPI HS Tx
> > * [3] = 0 : Power up MIPI LS Rx
> > * [2] = 1/0 : MIPI interface enable/disable
> > * [1:0] = 01/00: FIXME: 'debug'
> > */
> > ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00,
> > - on ? 0x45 : 0x40);
> > + on ? 0x5 | sensor->ep.bus.mipi_csi2.num_data_lanes << 5 :
> > + 0x40);
>
> You're writing 0x40 aka 2 lines now when turning the sensor off in 1 line mode.
>
> I believe this should be:
>
> ret = ov5640_write_reg(sensor, OV5640_REG_IO_MIPI_CTRL00,
> sensor->ep.bus.mipi_csi2.num_data_lanes << 5 |
> (on ? 0x05 : 0x0));
>
> Only changing the low nibble for on / off and always setting the correct
> lane count.
>
> Regards,
>
> Hans
>
>
>
© 2016 - 2026 Red Hat, Inc.