Hi Sakari,
2017-12-19 19:35 GMT+09:00 Sakari Ailus <sakari.ailus@xxxxxx>:
> Hi Akinobu,
>
> On Thu, Dec 14, 2017 at 01:00:49AM +0900, Akinobu Mita wrote:
>> This adds support VIDIOC_DBG_G/S_REGISTER ioctls.
>>
>> There are many device control registers contained in the OV9650. So
>> this helps debugging the lower level issues by getting and setting the
>> registers.
>>
>> Cc: Sylwester Nawrocki <sylvester.nawrocki@xxxxxxxxx>
>> Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
>> Cc: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx>
>
> Just wondering --- doesn't the I涎 user space interface offer essentially
> the same functionality?
You are right. I thought /dev/i2c-X interface is not allowed for the
i2c device that is currently in use by a driver. But I found that
there is I2C_SLAVE_FORCE ioctl to bypass the check and the i2cget and
i2cset with '-f' option use I2C_SLAVE_FORCE ioctls.
So I can live without the proposed patch.
> See: Documentation/i2c/dev-interface
>
> Cc Hans.
>
>> ---
>> drivers/media/i2c/ov9650.c | 36 ++++++++++++++++++++++++++++++++++++
>> 1 file changed, 36 insertions(+)
>>
>> diff --git a/drivers/media/i2c/ov9650.c b/drivers/media/i2c/ov9650.c
>> index 69433e1..c6462cf 100644
>> --- a/drivers/media/i2c/ov9650.c
>> +++ b/drivers/media/i2c/ov9650.c
>> @@ -1374,6 +1374,38 @@ static int ov965x_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
>> return 0;
>> }
>>
>> +#ifdef CONFIG_VIDEO_ADV_DEBUG
>> +
>> +static int ov965x_g_register(struct v4l2_subdev *sd,
>> + struct v4l2_dbg_register *reg)
>> +{
>> + struct i2c_client *client = v4l2_get_subdevdata(sd);
>> + u8 val = 0;
>> + int ret;
>> +
>> + if (reg->reg > 0xff)
>> + return -EINVAL;
>> +
>> + ret = ov965x_read(client, reg->reg, &val);
>> + reg->val = val;
>> + reg->size = 1;
>> +
>> + return ret;
>> +}
>> +
>> +static int ov965x_s_register(struct v4l2_subdev *sd,
>> + const struct v4l2_dbg_register *reg)
>> +{
>> + struct i2c_client *client = v4l2_get_subdevdata(sd);
>> +
>> + if (reg->reg > 0xff || reg->val > 0xff)
>> + return -EINVAL;
>> +
>> + return ov965x_write(client, reg->reg, reg->val);
>> +}
>> +
>> +#endif
>> +
>> static const struct v4l2_subdev_pad_ops ov965x_pad_ops = {
>> .enum_mbus_code = ov965x_enum_mbus_code,
>> .enum_frame_size = ov965x_enum_frame_sizes,
>> @@ -1397,6 +1429,10 @@ static const struct v4l2_subdev_core_ops ov965x_core_ops = {
>> .log_status = v4l2_ctrl_subdev_log_status,
>> .subscribe_event = v4l2_ctrl_subdev_subscribe_event,
>> .unsubscribe_event = v4l2_event_subdev_unsubscribe,
>> +#ifdef CONFIG_VIDEO_ADV_DEBUG
>> + .g_register = ov965x_g_register,
>> + .s_register = ov965x_s_register,
>> +#endif
>> };
>>
>> static const struct v4l2_subdev_ops ov965x_subdev_ops = {
>> --
>> 2.7.4
>>
>
> --
> Sakari Ailus
> e-mail: sakari.ailus@xxxxxx
