Hi Alex

On Thu, 2 Aug 2012, Alex Gershgorin wrote:

> Hi Guennadi,
> 
> Thank you for your very detailed comment.
> 
> > Hi Alex
> 
> > Yes, this looks much better to me now. Still, I'd like to ask you to
> > make a couple more changes. First - there are different opinions about how
> > really important a patch description is, whether there are at all cases,
> > when an empty description is acceptable. I do sometimes myself provide no
> > description and accept the same from others, but only in really trivial
> > cases, where the single patch subject line perfectly tells it all.
> > However, I don't think this is the case here. It would be nice to have a
> > couple of words in the patch description, saying, that "mt9v024 is a
> > camera sensor, very similar to mt9v022 with just a few differences, namely
> > its sensor matrix size is now ... instead of ..., some register locations
> > have changed,..."
> 
> No problem, I'll add descriptions.
> 
> > While at it, please, also change one more thing. Yes, it was my request to
> > move chip_id into the private struct, but now with the addition of "struct
> > mt9v02x_register" it is not needed anymore. The chip_id is only used in
> > the probe function, so, you don't have to save it. Please, if I'm not
> > mistaken and I haven't missed some additional uses of chip_id, remove it
> > again and just leave the local "data" variable without change.
> > Respectively, your is_mt9v024 macro will change to
> 
> > #define is_mt9v024(id) (id == 0x1324)
> 
> I only have a few doubts about this:
> mt9v024 camera sensor has about 20 additional registers that are not 
> supported in mt9v022 camera sensor.

I see...

> What should be happened if someone wants to add this registers?
> I guess, that in this case we will need to use the chip_id outside of the 
> probe function.
> What do you think?

Well, this can of course happen. But I think, it is better to add code 
when it is really needed, then try to guess in advance. If we had to 
decide between two alternative modifications to the code, then yes, taking 
into account possible future extensions might make sense. Whereas, when 
deciding between no-modification and a modification, that might be useful 
in the future, I think, the former is a safer bet.

Thanks
Guennadi

> 
> Regards,
> Alex
> 
>  
>  > Signed-off-by: Alex Gershgorin <al...@meprolight.com>
> > ---
> >  drivers/media/video/Kconfig   |    2 +-
> >  drivers/media/video/mt9v022.c |   45 
> > ++++++++++++++++++++++++++++++++--------
> >  2 files changed, 37 insertions(+), 10 deletions(-)
> >
> > Changes for v2:
> >         Fixed comment from Guennadi.
> >
> > diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
> > index c128fac..3ce905c 100644
> > --- a/drivers/media/video/Kconfig
> > +++ b/drivers/media/video/Kconfig
> > @@ -1058,7 +1058,7 @@ config SOC_CAMERA_MT9T112
> >         This driver supports MT9T112 cameras from Aptina.
> >
> >  config SOC_CAMERA_MT9V022
> > -     tristate "mt9v022 support"
> > +     tristate "mt9v022 and mt9v024 support"
> >       depends on SOC_CAMERA && I2C
> >       select GPIO_PCA953X if MT9V022_PCA9536_SWITCH
> >       help
> > diff --git a/drivers/media/video/mt9v022.c b/drivers/media/video/mt9v022.c
> > index 7247924..d46727b 100644
> > --- a/drivers/media/video/mt9v022.c
> > +++ b/drivers/media/video/mt9v022.c
> > @@ -57,6 +57,10 @@ MODULE_PARM_DESC(sensor_type, "Sensor type: \"colour\" 
> > or \"monochrome\"");
> >  #define MT9V022_AEC_AGC_ENABLE               0xAF
> >  #define MT9V022_MAX_TOTAL_SHUTTER_WIDTH      0xBD
> >
> > +/* mt9v024 partial list register addresses changes with respect to mt9v022 
> > */
> > +#define MT9V024_PIXCLK_FV_LV         0x72
> > +#define MT9V024_MAX_TOTAL_SHUTTER_WIDTH      0xAD
> > +
> >  /* Progressive scan, master, defaults */
> >  #define MT9V022_CHIP_CONTROL_DEFAULT 0x188
> >
> > @@ -67,6 +71,8 @@ MODULE_PARM_DESC(sensor_type, "Sensor type: \"colour\" or 
> > \"monochrome\"");
> >  #define MT9V022_COLUMN_SKIP          1
> >  #define MT9V022_ROW_SKIP             4
> >
> > +#define is_mt9v024(p) (p->chip_id == 0x1324)
> > +
> >  /* MT9V022 has only one fixed colorspace per pixelcode */
> >  struct mt9v022_datafmt {
> >       enum v4l2_mbus_pixelcode        code;
> > @@ -101,6 +107,22 @@ static const struct mt9v022_datafmt 
> > mt9v022_monochrome_fmts[] = {
> >       {V4L2_MBUS_FMT_Y8_1X8, V4L2_COLORSPACE_JPEG},
> >  };
> >
> > +/* only registers with different addresses on different mt9v02x sensors */
> > +struct mt9v02x_register {
> > +     u8      max_total_shutter_width;
> > +     u8      pixclk_fv_lv;
> > +};
> > +
> > +static const struct mt9v02x_register mt9v022_register = {
> > +     .max_total_shutter_width        = MT9V022_MAX_TOTAL_SHUTTER_WIDTH,
> > +     .pixclk_fv_lv                   = MT9V022_PIXCLK_FV_LV,
> > +};
> > +
> > +static const struct mt9v02x_register mt9v024_register = {
> > +     .max_total_shutter_width        = MT9V024_MAX_TOTAL_SHUTTER_WIDTH,
> > +     .pixclk_fv_lv                   = MT9V024_PIXCLK_FV_LV,
> > +};
> > +
> >  struct mt9v022 {
> >       struct v4l2_subdev subdev;
> >       struct v4l2_ctrl_handler hdl;
> > @@ -117,10 +139,12 @@ struct mt9v022 {
> >       struct v4l2_rect rect;  /* Sensor window */
> >       const struct mt9v022_datafmt *fmt;
> >       const struct mt9v022_datafmt *fmts;
> > +     const struct mt9v02x_register *reg;
> >       int num_fmts;
> >       int model;      /* V4L2_IDENT_MT9V022* codes from v4l2-chip-ident.h */
> >       u16 chip_control;
> >       unsigned short y_skip_top;      /* Lines to skip at the top */
> > +     s32 chip_id;
> >  };
> >
> >  static struct mt9v022 *to_mt9v022(const struct i2c_client *client)
> > @@ -185,7 +209,7 @@ static int mt9v022_init(struct i2c_client *client)
> >       if (!ret)
> >               ret = reg_write(client, MT9V022_TOTAL_SHUTTER_WIDTH, 480);
> >       if (!ret)
> > -             ret = reg_write(client, MT9V022_MAX_TOTAL_SHUTTER_WIDTH, 480);
> > +             ret = reg_write(client, 
> > mt9v022->reg->max_total_shutter_width, 480);
> >       if (!ret)
> >               /* default - auto */
> >               ret = reg_clear(client, MT9V022_BLACK_LEVEL_CALIB_CTRL, 1);
> > @@ -238,7 +262,7 @@ static int mt9v022_s_crop(struct v4l2_subdev *sd, 
> > struct v4l2_crop *a)
> >       ret = reg_read(client, MT9V022_AEC_AGC_ENABLE);
> >       if (ret >= 0) {
> >               if (ret & 1) /* Autoexposure */
> > -                     ret = reg_write(client, 
> > MT9V022_MAX_TOTAL_SHUTTER_WIDTH,
> > +                     ret = reg_write(client, 
> > mt9v022->reg->max_total_shutter_width,
> >                                       rect.height + mt9v022->y_skip_top + 
> > 43);
> >               else
> >                       ret = reg_write(client, MT9V022_TOTAL_SHUTTER_WIDTH,
> > @@ -566,21 +590,24 @@ static int mt9v022_video_probe(struct i2c_client 
> > *client)
> >  {
> >       struct mt9v022 *mt9v022 = to_mt9v022(client);
> >       struct soc_camera_link *icl = soc_camera_i2c_to_link(client);
> > -     s32 data;
> >       int ret;
> >       unsigned long flags;
> >
> >       /* Read out the chip version register */
> > -     data = reg_read(client, MT9V022_CHIP_VERSION);
> > +     mt9v022->chip_id = reg_read(client, MT9V022_CHIP_VERSION);
> >
> > -     /* must be 0x1311 or 0x1313 */
> > -     if (data != 0x1311 && data != 0x1313) {
> > +     /* must be 0x1311, 0x1313 or 0x1324 */
> > +     if (mt9v022->chip_id != 0x1311 && mt9v022->chip_id != 0x1313 &&
> > +             mt9v022->chip_id != 0x1324) {
> >               ret = -ENODEV;
> >               dev_info(&client->dev, "No MT9V022 found, ID register 0x%x\n",
> > -                      data);
> > +                      mt9v022->chip_id);
> >               goto ei2c;
> >       }
> >
> > +     mt9v022->reg = is_mt9v024(mt9v022) ? &mt9v024_register :
> > +                     &mt9v022_register;
> > +
> >       /* Soft reset */
> >       ret = reg_write(client, MT9V022_RESET, 1);
> >       if (ret < 0)
> > @@ -632,7 +659,7 @@ static int mt9v022_video_probe(struct i2c_client 
> > *client)
> >       mt9v022->fmt = &mt9v022->fmts[0];
> >
> >       dev_info(&client->dev, "Detected a MT9V022 chip ID %x, %s sensor\n",
> > -              data, mt9v022->model == V4L2_IDENT_MT9V022IX7ATM ?
> > +              mt9v022->chip_id, mt9v022->model == V4L2_IDENT_MT9V022IX7ATM 
> > ?
> >                "monochrome" : "colour");
> >
> >       ret = mt9v022_init(client);
> > @@ -728,7 +755,7 @@ static int mt9v022_s_mbus_config(struct v4l2_subdev *sd,
> >       if (!(flags & V4L2_MBUS_VSYNC_ACTIVE_HIGH))
> >               pixclk |= 0x2;
> >
> > -     ret = reg_write(client, MT9V022_PIXCLK_FV_LV, pixclk);
> > +     ret = reg_write(client, mt9v022->reg->pixclk_fv_lv, pixclk);
> >       if (ret < 0)
> >               return ret;
> >
> > --
> > 1.7.0.4
> >
> 
> ---
> Guennadi Liakhovetski, Ph.D.
> Freelance Open-Source Software Developer
> http://www.open-technology.de/

---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/
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