Re: [PATCH 2/3] media: atomisp: ov2680: Convert to new CCI register access helpers

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 6/6/23 22:53, Andy Shevchenko wrote:
> On Tue, Jun 6, 2023 at 7:58 PM Hans de Goede <hdegoede@redhat.com> wrote:
>>
>> Use the new comon CCI register access helpers to replace the private
>> register access helpers in the ov2680 driver.
>>
>> While at it also switch to using the same register address defines
>> as the standard drivers/media/i2c/ov2680.c driver to make merging
>> the 2 drivers simpler.
> 
> ...
> 
>> +       cci_write(sensor->regmap, OV2680_REG_SENSOR_CTRL_0A, sensor_ctrl_0a, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_HORIZONTAL_START, sensor->mode.h_start, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_VERTICAL_START, sensor->mode.v_start, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_HORIZONTAL_END, sensor->mode.h_end, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_VERTICAL_END, sensor->mode.v_end, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_HORIZONTAL_OUTPUT_SIZE,
>> +                 sensor->mode.h_output_size, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_VERTICAL_OUTPUT_SIZE,
>> +                 sensor->mode.v_output_size, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_TIMING_HTS, sensor->mode.hts, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_TIMING_VTS, sensor->mode.vts, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_ISP_X_WIN, 0, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_ISP_Y_WIN, 0, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_X_INC, inc, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_Y_INC, inc, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_X_WIN, sensor->mode.h_output_size, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_Y_WIN, sensor->mode.v_output_size, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_FORMAT1, fmt1, &ret);
>> +       cci_write(sensor->regmap, OV2680_REG_FORMAT2, fmt2, &ret);
> 
> I know that &ret thingy was discussed before and Laurent is keen to
> have this, but has anybody actually tested how bad or not at all the
> code generation becomes?

The cci_write function is in another module, so it won't be inlined and as such I don't see how the code generation can become bad. We loose all the if (ret) return ret; checks here, so the code should become smaller.

Or are you worried about having to pass the 1 extra parameter ?


> 
> ...
> 
>> +       struct device *dev;
>> +       struct regmap *regmap;
> 
> Isn't the same device associated with regmap? If so, one of them
> probably duplicates the other.

You are right, but the entire atomisp-ov2680.c file is going away real soon now. I plan to post a series to get drivers/media/i2c/ov2680.c ready to replace it later today.

So I'm not even sure if this patch should be merged, as I mentioned in the cover letter this one is mostly here to illustrate use of the new helpers.

I also wrote this patch to make porting recent atomisp-ov2680.c changes over to drivers/media/i2c/ov2680.c easier. Part of the series to get drivers/media/i2c/ov2680.c into shape is converting it to the new CCI helpers so that I could then easily copy over bits from the also converted atomisp-ov2680.c.

So it might be interesting to still merge this so that the latest state of atomisp-ov2680.c is easier to compare to drivers/media/i2c/ov2680.c if the need arises.

Regards,

Hans