Re: [PATCH 2/2] media: i2c: imx290: Add support for the mono sensor variant.

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Dave,

On Thu, Feb 02, 2023 at 11:20:14AM +0000, Dave Stevenson wrote:
> On Thu, 2 Feb 2023 at 00:15, Laurent Pinchart wrote:
> > On Wed, Feb 01, 2023 at 08:03:36AM +0100, Alexander Stein wrote:
> > > Am Dienstag, 31. Januar 2023, 20:07:00 CET schrieb Dave Stevenson:
> > > > The IMX290 module is available as either mono or colour (Bayer).
> > > >
> > > > Update the driver so that it can advertise the correct mono
> > > > formats instead of the colour ones.
> > > >
> > > > Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> > > > ---
> > > >  drivers/media/i2c/imx290.c | 47 ++++++++++++++++++++++++--------------
> > > >  1 file changed, 30 insertions(+), 17 deletions(-)
> > > >
> > > > diff --git a/drivers/media/i2c/imx290.c b/drivers/media/i2c/imx290.c
> > > > index 49d6c8bdec41..a370f1102334 100644
> > > > --- a/drivers/media/i2c/imx290.c
> > > > +++ b/drivers/media/i2c/imx290.c
> > > > @@ -13,6 +13,7 @@
> > > >  #include <linux/gpio/consumer.h>
> > > >  #include <linux/i2c.h>
> > > >  #include <linux/module.h>
> > > > +#include <linux/of_device.h>
> > > >  #include <linux/pm_runtime.h>
> > > >  #include <linux/regmap.h>
> > > >  #include <linux/regulator/consumer.h>
> > > > @@ -177,6 +178,7 @@ struct imx290 {
> > > >     struct clk *xclk;
> > > >     struct regmap *regmap;
> > > >     u8 nlanes;
> > > > +   u8 mono;
> > > >
> > > >     struct v4l2_subdev sd;
> > > >     struct media_pad pad;
> > > > @@ -414,7 +416,8 @@ static inline int imx290_modes_num(const struct imx290 *imx290) }
> > > >
> > > >  struct imx290_format_info {
> > > > -   u32 code;
> > > > +   /* Array of codes. [0] is for colour, [1] is for mono. */
> > > > +   u32 code[2];
> > >
> > > Please use a define for that.
> > >
> > > >     u8 bpp;
> > > >     const struct imx290_regval *regs;
> > > >     unsigned int num_regs;
> > > > @@ -422,26 +425,27 @@ struct imx290_format_info {
> > > >
> > > >  static const struct imx290_format_info imx290_formats[] = {
> > > >     {
> > > > -           .code = MEDIA_BUS_FMT_SRGGB10_1X10,
> > > > +           .code = { MEDIA_BUS_FMT_SRGGB10_1X10, MEDIA_BUS_FMT_Y10_1X10 },
> > > >             .bpp = 10,
> > > >             .regs = imx290_10bit_settings,
> > > >             .num_regs = ARRAY_SIZE(imx290_10bit_settings),
> > > >     }, {
> > > > -           .code = MEDIA_BUS_FMT_SRGGB12_1X12,
> > > > +           .code = { MEDIA_BUS_FMT_SRGGB12_1X12, MEDIA_BUS_FMT_Y12_1X12 },
> > > >             .bpp = 12,
> > > >             .regs = imx290_12bit_settings,
> > > >             .num_regs = ARRAY_SIZE(imx290_12bit_settings),
> > > >     }
> > > >  };
> > > >
> > > > -static const struct imx290_format_info *imx290_format_info(u32 code)
> > > > +static const struct imx290_format_info *
> > > > +imx290_format_info(const struct imx290 *imx290, u32 code)
> > > >  {
> > > >     unsigned int i;
> > > >
> > > >     for (i = 0; i < ARRAY_SIZE(imx290_formats); ++i) {
> > > >             const struct imx290_format_info *info = &imx290_formats[i];
> > > >
> > > > -           if (info->code == code)
> > > > +           if (info->code[imx290->mono] == code)
> > > >                     return info;
> > > >     }
> > > >
> > > > @@ -536,7 +540,7 @@ static int imx290_set_black_level(struct imx290 *imx290,
> > > > const struct v4l2_mbus_framefmt *format,
> > > >                               unsigned int black_level, int *err)
> > > >  {
> > > > -   unsigned int bpp = imx290_format_info(format->code)->bpp;
> > > > +   unsigned int bpp = imx290_format_info(imx290, format->code)->bpp;
> > > >
> > > >     return imx290_write(imx290, IMX290_BLKLEVEL,
> > > >                         black_level >> (16 - bpp), err);
> > > > @@ -548,7 +552,7 @@ static int imx290_setup_format(struct imx290 *imx290,
> > > >     const struct imx290_format_info *info;
> > > >     int ret;
> > > >
> > > > -   info = imx290_format_info(format->code);
> > > > +   info = imx290_format_info(imx290, format->code);
> > > >
> > > >     ret = imx290_set_register_array(imx290, info->regs, info->num_regs);
> > > >     if (ret < 0) {
> > > > @@ -844,10 +848,12 @@ static int imx290_enum_mbus_code(struct v4l2_subdev
> > > > *sd, struct v4l2_subdev_state *sd_state,
> > > >                              struct v4l2_subdev_mbus_code_enum *code)
> > > >  {
> > > > +   const struct imx290 *imx290 = to_imx290(sd);
> > > > +
> > > >     if (code->index >= ARRAY_SIZE(imx290_formats))
> > > >             return -EINVAL;
> > > >
> > > > -   code->code = imx290_formats[code->index].code;
> > > > +   code->code = imx290_formats[code->index].code[imx290->mono];
> > > >
> > > >     return 0;
> > > >  }
> > > > @@ -859,7 +865,7 @@ static int imx290_enum_frame_size(struct v4l2_subdev
> > > > *sd, const struct imx290 *imx290 = to_imx290(sd);
> > > >     const struct imx290_mode *imx290_modes = imx290_modes_ptr(imx290);
> > > >
> > > > -   if (!imx290_format_info(fse->code))
> > > > +   if (!imx290_format_info(imx290, fse->code))
> > > >             return -EINVAL;
> > > >
> > > >     if (fse->index >= imx290_modes_num(imx290))
> > > > @@ -888,8 +894,8 @@ static int imx290_set_fmt(struct v4l2_subdev *sd,
> > > >     fmt->format.width = mode->width;
> > > >     fmt->format.height = mode->height;
> > > >
> > > > -   if (!imx290_format_info(fmt->format.code))
> > > > -           fmt->format.code = imx290_formats[0].code;
> > > > +   if (!imx290_format_info(imx290, fmt->format.code))
> > > > +           fmt->format.code = imx290_formats[0].code[imx290->mono];
> > > >
> > > >     fmt->format.field = V4L2_FIELD_NONE;
> > > >
> > > > @@ -1177,16 +1183,29 @@ static s64 imx290_check_link_freqs(const struct
> > > > imx290 *imx290, return 0;
> > > >  }
> > > >
> > > > +static const struct of_device_id imx290_of_match[] = {
> > > > +   { .compatible = "sony,imx290" },
> > > > +   { .compatible = "sony,imx290-mono", .data = (void *)1 },
> > >
> > > Would you mind using a model specific struct? I have a patch on my stack
> > > adding support for imx327. There are some imx327 specific writes to registers
> > > during initialization. I do not mind adding this struct later though.
> >
> > If not a structure already, at least an enum
> >
> > enum imx290_model {
> >         IMX290_MODEL_COLOUR,
> >         IMX290_MODEL_MONO,
> > };
> >
> > > > +   { /* sentinel */ }
> > > > +};
> > > > +MODULE_DEVICE_TABLE(of, imx290_of_match);
> > > > +
> > > >  static int imx290_parse_dt(struct imx290 *imx290)
> > > >  {
> > > > +   struct i2c_client *client = to_i2c_client(imx290->dev);
> > > >     /* Only CSI2 is supported for now: */
> > > >     struct v4l2_fwnode_endpoint ep = {
> > > >             .bus_type = V4L2_MBUS_CSI2_DPHY
> > > >     };
> > > > +   const struct of_device_id *match;
> > > >     struct fwnode_handle *endpoint;
> > > >     int ret;
> > > >     s64 fq;
> > > >
> > > > +   match = i2c_of_match_device(imx290_of_match, client);
> > > > +   if (match)
> > > > +           imx290->mono = match->data ? 1 : 0;
> > > > +
> >
> > You can simplify this to
> >
> >         imx290->mono = (enum imx290_model)of_device_get_match_data(imx290->dev);
> >
> > which may then be best placed in the probe function.
> >
> > I'd be tempted to rename the imx290 mono field to model as the above
> > looks weird, but if Alexander needs a structure anyway, we may also just
> > do it right away:
> >
> > enum imx290_model {
> >         IMX290_MODEL_COLOUR,
> >         IMX290_MODEL_MONO,
> > };
> >
> > struct imx290_model_info {
> >         bool mono;
> > };
> 
> To my mind this gets confusing as to whether imx290_model is the
> mono/colour switch reference for finding a code in imx290_formats, or
> differentiating between imx290llr (mono), imx290lqr (colour),
> imx327xyz, etc as different models of the sensor. (Having the IMX290
> prefix because it is in the imx290 driver will get even more confusing
> when you get IMX290_MODEL_IMX327_COLOUR).
> 
> Alexander was asking for a define to set the size of code in struct
> imx290_format_info. As you also point out above, switching to using an
> enum makes more sense, and then you can add a _MAX to get the array
> size.
> 
> enum imx290_colour_variant {
>         IMX290_VARIANT_COLOUR,
>         IMX290_VARIANT_MONO,
>         IMX290_VARIANT_MAX
> };
> 
> enum imx290_model {
>         IMX290_MODEL_IMX290LLR,
>         IMX290_MODEL_IMX290LQR,
> /*
>         IMX290_MODEL_IMX327LQR,
>         IMX290_MODEL_IMX462LQR,
>         IMX290_MODEL_IMX462LLR,
>         etc,
> */
> };
> 
> static const struct imx290_model_info imx290_models[] = {
>         [IMX290_MODEL_IMX290LQR]= {
>                 .colour_variant = IMX290_VARIANT_COLOUR,
>         },
>         [IMX290_MODEL_IMX290LLR] = {
>                 .colour_variant = IMX290_VARIANT_MONO,
>         },
> };
> 
> Thoughts?

I like the above :-)

> Otherwise I will drop back to the simplest option - I'm afraid I
> haven't got masses of time to be messing about revising patches at
> present.

No worries. I can also improve things on top if needed.

> > static const struct imx290_model_info imx290_models[] = {
> >         [IMX290_MODEL_COLOUR] = {
> >                 .mono = false,
> >         },
> >         [IMX290_MODEL_MONO] = {
> >                 .mono = true,
> >         },
> > };
> >
> > static const struct of_device_id imx290_of_match[] = {
> >         {
> >                 .compatible = "sony,imx290",
> >                 .data = &imx290_models[IMX290_MODEL_COLOUR],
> >         },
> >         {
> >                 .compatible = "sony,imx290-mono",
> >                 .data = &imx290_models[IMX290_MODEL_MONO],
> >         },
> >         { /* sentinel */ },
> > };
> >
> > ...
> >
> >         imx290->model = of_device_get_match_data(imx290->dev);
> >
> > and use imx290->model->mono instead of imx290->mono through the code.
> >
> > I'm OK if you don't want this additional complexity yet, but the code is
> > here already and will be needed soon :-)
> >
> > > >     endpoint = fwnode_graph_get_next_endpoint(dev_fwnode(imx290->dev), NULL);
> > > >     if (!endpoint) {
> > > >             dev_err(imx290->dev, "Endpoint node not found\n");
> > > > @@ -1351,12 +1370,6 @@ static void imx290_remove(struct i2c_client *client)
> > > >     pm_runtime_set_suspended(imx290->dev);
> > > >  }
> > > >
> > > > -static const struct of_device_id imx290_of_match[] = {
> > > > -   { .compatible = "sony,imx290" },
> > > > -   { /* sentinel */ }
> > > > -};
> > > > -MODULE_DEVICE_TABLE(of, imx290_of_match);
> > > > -
> > > >  static struct i2c_driver imx290_i2c_driver = {
> > > >     .probe_new  = imx290_probe,
> > > >     .remove = imx290_remove,

-- 
Regards,

Laurent Pinchart