Re: [PATCH 1/2] media: mt9p031: Extend match support for OF tables

[Laurent Pinchart]

Hello,

On Mon, Sep 11, 2023 at 11:25:03AM +0200, Jacopo Mondi wrote:
> On Mon, Sep 11, 2023 at 09:14:35AM +0000, Biju Das wrote:
> > > Subject: Re: [PATCH 1/2] media: mt9p031: Extend match support for OF tables
> > >
> > > Hi Biju
> > >
> > > On Sun, Sep 10, 2023 at 05:01:25PM +0100, Biju Das wrote:
> > > > The driver has an OF match table, still, it uses an ID lookup table
> > > > for retrieving match data. Currently, the driver is working on the
> > > > assumption that an I2C device registered via OF will always match a
> > > > legacy I2C device ID. The correct approach is to have an OF device ID
> > > > table using i2c_get_match_data() if the devices are registered via OF/ID.
> > > >
> > > > Unify the OF/ID table by using MEDIA_BUS_FMT as match data for both
> > > > these tables and replace the ID lookup table for the match data by
> > > > i2c_get_match_data() and simplifly probe() and mt9p031_init_cfg()
> > > >
> > > > Drop mt9p031_init_cfg as there is no user.
> > > >
> > > > While at it, remove the trailing comma in the terminator entry for the
> > > > OF table making code robust against (theoretical) misrebases or other
> > > > similar things where the new entry goes _after_ the termination
> > > > without the compiler noticing.
> > > >
> > > > Signed-off-by: Biju Das <biju.das.jz@xxxxxxxxxxxxxx>
> > > > ---
> > > >  drivers/media/i2c/mt9p031.c | 33 +++++++++++----------------------
> > > >  1 file changed, 11 insertions(+), 22 deletions(-)
> > > >
> > > > diff --git a/drivers/media/i2c/mt9p031.c b/drivers/media/i2c/mt9p031.c
> > > > index 348f1e1098fb..540cb519915c 100644
> > > > --- a/drivers/media/i2c/mt9p031.c
> > > > +++ b/drivers/media/i2c/mt9p031.c
> > > > @@ -112,11 +112,6 @@
> > > >  #define MT9P031_TEST_PATTERN_RED			0xa2
> > > >  #define MT9P031_TEST_PATTERN_BLUE			0xa3
> > > >
> > > > -enum mt9p031_model {
> > > > -	MT9P031_MODEL_COLOR,
> > > > -	MT9P031_MODEL_MONOCHROME,
> > > > -};
> > > > -
> > > >  struct mt9p031 {
> > > >  	struct v4l2_subdev subdev;
> > > >  	struct media_pad pad;
> > > > @@ -129,7 +124,7 @@ struct mt9p031 {
> > > >  	struct clk *clk;
> > > >  	struct regulator_bulk_data regulators[3];
> > > >
> > > > -	enum mt9p031_model model;
> > > > +	u32 code;
> > > >  	struct aptina_pll pll;
> > > >  	unsigned int clk_div;
> > > >  	bool use_pll;
> > > > @@ -714,12 +709,7 @@ static int mt9p031_init_cfg(struct v4l2_subdev *subdev,
> > > >  	crop->height = MT9P031_WINDOW_HEIGHT_DEF;
> > > >
> > > >  	format = __mt9p031_get_pad_format(mt9p031, sd_state, 0, which);
> > > > -
> > > > -	if (mt9p031->model == MT9P031_MODEL_MONOCHROME)
> > > > -		format->code = MEDIA_BUS_FMT_Y12_1X12;
> > > > -	else
> > > > -		format->code = MEDIA_BUS_FMT_SGRBG12_1X12;
> > > > -
> > > > +	format->code = mt9p031->code;
> > > >  	format->width = MT9P031_WINDOW_WIDTH_DEF;
> > > >  	format->height = MT9P031_WINDOW_HEIGHT_DEF;
> > > >  	format->field = V4L2_FIELD_NONE;
> > > > @@ -1104,7 +1094,6 @@ mt9p031_get_pdata(struct i2c_client *client)
> > > >
> > > >  static int mt9p031_probe(struct i2c_client *client)  {
> > > > -	const struct i2c_device_id *did = i2c_client_get_device_id(client);
> > > >  	struct mt9p031_platform_data *pdata = mt9p031_get_pdata(client);
> > > >  	struct i2c_adapter *adapter = client->adapter;
> > > >  	struct mt9p031 *mt9p031;
> > > > @@ -1129,7 +1118,7 @@ static int mt9p031_probe(struct i2c_client *client)
> > > >  	mt9p031->pdata = pdata;
> > > >  	mt9p031->output_control	= MT9P031_OUTPUT_CONTROL_DEF;
> > > >  	mt9p031->mode2 = MT9P031_READ_MODE_2_ROW_BLC;
> > > > -	mt9p031->model = did->driver_data;
> > > > +	mt9p031->code = (uintptr_t)i2c_get_match_data(client);
> > > >
> > > >  	mt9p031->regulators[0].supply = "vdd";
> > > >  	mt9p031->regulators[1].supply = "vdd_io";
> > > > @@ -1226,19 +1215,19 @@ static void mt9p031_remove(struct i2c_client *client)
> > > >  }
> > > >
> > > >  static const struct i2c_device_id mt9p031_id[] = {
> > > > -	{ "mt9p006", MT9P031_MODEL_COLOR },
> > > > -	{ "mt9p031", MT9P031_MODEL_COLOR },
> > > > -	{ "mt9p031m", MT9P031_MODEL_MONOCHROME },
> > > > -	{ }
> > > > +	{ "mt9p006", MEDIA_BUS_FMT_SGRBG12_1X12 },
> > > > +	{ "mt9p031", MEDIA_BUS_FMT_SGRBG12_1X12 },
> > > > +	{ "mt9p031m", MEDIA_BUS_FMT_Y12_1X12 },
> > > > +	{ /* sentinel */ }
> > > >  };
> > > >  MODULE_DEVICE_TABLE(i2c, mt9p031_id);
> > > >
> > > >  #if IS_ENABLED(CONFIG_OF)
> > > >  static const struct of_device_id mt9p031_of_match[] = {
> > > > -	{ .compatible = "aptina,mt9p006", },
> > > > -	{ .compatible = "aptina,mt9p031", },
> > > > -	{ .compatible = "aptina,mt9p031m", },
> > > > -	{ /* sentinel */ },
> > > > +	{ .compatible = "aptina,mt9p006", .data = (void *)MEDIA_BUS_FMT_SGRBG12_1X12 },
> > > > +	{ .compatible = "aptina,mt9p031", .data = (void *)MEDIA_BUS_FMT_SGRBG12_1X12 },
> > > > +	{ .compatible = "aptina,mt9p031m", .data = (void *)MEDIA_BUS_FMT_Y12_1X12 },
> > > > +	{ /* sentinel */ }
> > >
> > > I know it might sound not necessary, but isn't it better to wrap the
> > > format in some sort of per-model structure. It would avoid a few type
> > > casts too. Up to you though
> >
> > The problem with structure is, it will have one
> > variable entry. I got some feedback related to similar
> > patches not to add a single variable to structure
> > and use the value directly instead.
> 
> Ok then, a matter of preferences I think. Up to you, really.

My preference actually goes for a structure too.

Given how long it took me to review this, I'll send a v2 of the series
myself.

> > > >  };
> > > >  MODULE_DEVICE_TABLE(of, mt9p031_of_match);
> > > >  #endif

-- 
Regards,

Laurent Pinchart