Re: [RFC PATCH] [media] mt9v032: Add support for mt9v022 and mt9v024

Philipp Zabel
2014-05-28T14:37:11Z

Hi Laurent,

Am Mittwoch, den 28.05.2014, 13:43 +0200 schrieb Laurent Pinchart:
> Hi Philipp,
>
> Thank you for the patch.
>
> On Monday 26 May 2014 16:03:05 Philipp Zabel wrote:
> > From the looks of it, mt9v022 and mt9v032 are very similar,
> > as are mt9v024 and mt9v034. With minimal changes it is possible
> > to support mt9v02[24] with the same driver.
> >
> > Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
> > ---
> > drivers/media/i2c/mt9v032.c | 56 ++++++++++++++++++++++++++++++------------
> > 1 file changed, 42 insertions(+), 14 deletions(-)
> >
> > diff --git a/drivers/media/i2c/mt9v032.c b/drivers/media/i2c/mt9v032.c
> > index 052e754..617b77f 100644
> > --- a/drivers/media/i2c/mt9v032.c
> > +++ b/drivers/media/i2c/mt9v032.c
[...]
> > @@ -426,11 +446,9 @@ static int mt9v032_s_stream(struct v4l2_subdev *subdev,
> > int enable) /* Configure the window size and row/column bin */
> > hbin = fls(mt9v032->hratio) - 1;
> > vbin = fls(mt9v032->vratio) - 1;
> > - read_mode = mt9v032_read(client, MT9V032_READ_MODE);
> > - read_mode &= ~0xff; /* bits 0x300 are reserved, on MT9V024 */
> > - read_mode |= hbin << MT9V032_READ_MODE_COLUMN_BIN_SHIFT |
> > - vbin << MT9V032_READ_MODE_ROW_BIN_SHIFT;
> > - ret = mt9v032_write(client, MT9V032_READ_MODE, read_mode);
> > + ret = mt9v032_write(client, MT9V032_READ_MODE,
> > + hbin << MT9V032_READ_MODE_COLUMN_BIN_SHIFT |
> > + vbin << MT9V032_READ_MODE_ROW_BIN_SHIFT);
>
> Doesn't this change completely reverse one of your previous patches ? Is it
> needed, or is it included here by mistake ?

That was by mistake. It answers the question whether or not the mt9v02x
sensors work without this change, though: Clearing those two bits
doesn't seem to hurt.

> > if (ret < 0)
> > return ret;
> >
> > @@ -902,6 +920,12 @@ static int mt9v032_probe(struct i2c_client *client,
> > mt9v032->pdata = pdata;
> > mt9v032->model = (const void *)did->driver_data;
> >
> > + /* Keep defective pixel correction enabled on MT9V024 */
> > + ret = mt9v032_read(client, MT9V032_CHIP_CONTROL);
> > + if (ret < 0)
> > + return ret;
> > + mt9v032->chip_control = ret & MT9V024_CHIP_CONTROL_DEF_PIX_CORRECT;
>
> On the MT9V034 bit 9 is marked as reserved according to revision A of the
> datasheet, defaults to 1 after power-up and must be written to 0 for proper
> operation. This could thus break operation on the MT9V034. I don't have a copy
> of the MT9V022 register reference manual to check what happens on that chip
> though.

I have seen this described as defect pixel correction enable bit on
mt9v022 in this document:
http://www.videologyinc.com/media/products/application%20notes/APN-24B752XA.pdf

The mt9v02x sensors still seem to work without this bit enabled.
I could split this out into a separate patch.

> > +
> > v4l2_ctrl_handler_init(&mt9v032->ctrls, 10);
> >
> > v4l2_ctrl_new_std(&mt9v032->ctrls, &mt9v032_ctrl_ops,
> > @@ -1015,6 +1039,10 @@ static int mt9v032_remove(struct i2c_client *client)
> > }
> >
> > static const struct i2c_device_id mt9v032_id[] = {
> > + { "mt9v022", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V022_COLOR] },
> > + { "mt9v022m", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V022_MONO] },
> > + { "mt9v024", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V024_COLOR] },
> > + { "mt9v024m", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V024_MONO] },
> > { "mt9v032", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V032_COLOR] },
> > { "mt9v032m", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V032_MONO] },
> > { "mt9v034", (kernel_ulong_t)&mt9v032_models[MT9V032_MODEL_V034_COLOR] },

regards
Philipp