Re: [RFC v2 1/2] saa7115: Implement i2c_board_info.platform_data

From: Jon Arne JÃrgensen
Date: Sun Jun 09 2013 - 16:18:20 EST

On Sun, Jun 09, 2013 at 11:36:55AM +0200, Hans Verkuil wrote:
> On Sat June 8 2013 19:29:41 Jon Arne JÃrgensen wrote:
> > On Fri, Jun 07, 2013 at 11:12:47AM +0200, Hans Verkuil wrote:
> > > On Fri May 31 2013 13:40:25 Jon Arne JÃrgensen wrote:
> > > > Implement i2c_board_info.platform_data handling in the driver so we can
> > > > make device specific changes to the chips we support.
> > > >
> > > > Signed-off-by: Jon Arne JÃrgensen <jonarne@xxxxxxxxxx>
> > > > ---
> > > > drivers/media/i2c/saa7115.c | 101 +++++++++++++++++++++++++++++++++++++--
> > > > drivers/media/i2c/saa711x_regs.h | 8 ++++
> > > > include/media/saa7115.h | 39 +++++++++++++++
> > > > 3 files changed, 143 insertions(+), 5 deletions(-)
> > > >
> > > > diff --git a/drivers/media/i2c/saa7115.c b/drivers/media/i2c/saa7115.c
> > > > index d6f589a..4a52b4d 100644
> > > > --- a/drivers/media/i2c/saa7115.c
> > > > +++ b/drivers/media/i2c/saa7115.c
> > > > @@ -216,10 +216,7 @@ static const unsigned char saa7111_init[] = {
> > > > 0x00, 0x00
> > > > };
> > > >
> > > > -/* SAA7113/GM7113C init codes
> > > > - * It's important that R_14... R_17 == 0x00
> > > > - * for the gm7113c chip to deliver stable video
> > > > - */
> > > > +/* SAA7113/GM7113C init codes */
> > > > static const unsigned char saa7113_init[] = {
> > > > R_01_INC_DELAY, 0x08,
> > > > R_02_INPUT_CNTL_1, 0xc2,
> > > > @@ -248,6 +245,35 @@ static const unsigned char saa7113_init[] = {
> > > > 0x00, 0x00
> > > > };
> > > >
> > > > +/* SAA7113 Init according to the datasheet */
> > > > +static const unsigned char saa7113_datasheet_init[] = {
> > > > + R_01_INC_DELAY, 0x08,
> > > > + R_02_INPUT_CNTL_1, 0xc0,
> > > > + R_03_INPUT_CNTL_2, 0x33,
> > > > + R_04_INPUT_CNTL_3, 0x00,
> > > > + R_05_INPUT_CNTL_4, 0x00,
> > > > + R_06_H_SYNC_START, 0xe9,
> > > > + R_07_H_SYNC_STOP, 0x0d,
> > > > + R_08_SYNC_CNTL, 0x98,
> > > > + R_09_LUMA_CNTL, 0x01,
> > > > + R_0A_LUMA_BRIGHT_CNTL, 0x80,
> > > > + R_0B_LUMA_CONTRAST_CNTL, 0x47,
> > > > + R_0C_CHROMA_SAT_CNTL, 0x40,
> > > > + R_0D_CHROMA_HUE_CNTL, 0x00,
> > > > + R_0E_CHROMA_CNTL_1, 0x01,
> > > > + R_0F_CHROMA_GAIN_CNTL, 0x2a,
> > > > + R_10_CHROMA_CNTL_2, 0x00,
> > > > + R_11_MODE_DELAY_CNTL, 0x0c,
> > > > + R_12_RT_SIGNAL_CNTL, 0x01,
> > > > + R_13_RT_X_PORT_OUT_CNTL, 0x00,
> > > > + R_14_ANAL_ADC_COMPAT_CNTL, 0x00,
> > > > + R_15_VGATE_START_FID_CHG, 0x00,
> > > > + R_16_VGATE_STOP, 0x00,
> > > > + R_17_MISC_VGATE_CONF_AND_MSB, 0x00,
> > > > +
> > > > + 0x00, 0x00
> > > > +};
> > > > +
> > > > /* If a value differs from the Hauppauge driver values, then the comment starts with
> > > > 'was 0xXX' to denote the Hauppauge value. Otherwise the value is identical to what the
> > > > Hauppauge driver sets. */
> > > > @@ -1603,6 +1629,64 @@ static const struct v4l2_subdev_ops saa711x_ops = {
> > > > };
> > > >
> > > > /* ----------------------------------------------------------------------- */
> > > > +static void saa711x_write_platform_data(struct saa711x_state *state,
> > > > + struct saa7115_platform_data *data)
> > > > +{
> > > > + struct v4l2_subdev *sd = &state->sd;
> > > > + u8 work;
> > > > +
> > > > + if (state->ident != V4L2_IDENT_GM7113C)
> > > > + return;
> > > > +
> > > > + if (data->horizontal_time_const) {
> > > > + work = saa711x_read(sd, R_08_SYNC_CNTL);
> > > > + work &= ~SAA7113_R_08_HTC_MASK;
> > > > + work |= ((data->horizontal_time_const >> 1) << 3);
> > > > + v4l2_dbg(1, debug, sd,
> > > > + "set R_08 horizontal_time_const: 0x%x\n", work);
> > > > + saa711x_write(sd, R_08_SYNC_CNTL, work);
> > > > + }
> > > > +
> > > > + if (data->vref_len) {
> > > > + work = saa711x_read(sd, R_10_CHROMA_CNTL_2);
> > > > + work &= ~SAA7113_R_10_VRLN_MASK;
> > > > + work |= (1 << 3);
> > > > + v4l2_dbg(1, debug, sd, "set R_10 vref_len: 0x%x\n", work);
> > > > + saa711x_write(sd, R_10_CHROMA_CNTL_2, work);
> > > > + }
> > > > +
> > > > + if (data->output_format != SAA7113_OFTS_STD_ITU_656) {
> > > > + work = saa711x_read(sd, R_10_CHROMA_CNTL_2);
> > > > + work &= ~SAA7113_R_10_OFTS_MASK;
> > > > + work |= (data->output_format << 6);
> > > > + v4l2_dbg(1, debug, sd, "set R_10 output_format: 0x%x\n", work);
> > > > + saa711x_write(sd, R_10_CHROMA_CNTL_2, work);
> > > > + }
> > > > +
> > > > + if (data->rt_signal0) {
> > > > + work = saa711x_read(sd, R_12_RT_SIGNAL_CNTL);
> > > > + work &= ~SAA7113_R_12_RTS0_MASK;
> > > > + work |= data->rt_signal0;
> > > > + v4l2_dbg(1, debug, sd, "set R_12 rt_signal0: 0x%x\n", work);
> > > > + saa711x_write(sd, R_12_RT_SIGNAL_CNTL, work);
> > > > + }
> > > > +
> > > > + if (data->rt_signal1) {
> > > > + work = saa711x_read(sd, R_12_RT_SIGNAL_CNTL);
> > > > + work &= ~SAA7113_R_12_RTS1_MASK;
> > > > + work |= (data->rt_signal1 << 4);
> > > > + v4l2_dbg(1, debug, sd, "set R_12 rt_signal1: 0x%x\n", work);
> > > > + saa711x_write(sd, R_12_RT_SIGNAL_CNTL, work);
> > > > + }
> > > > +
> > > > + if (data->adc_lsb) {
> > > > + work = saa711x_read(sd, R_13_RT_X_PORT_OUT_CNTL);
> > > > + work &= ~SAA7113_R_13_ADLSB_MASK;
> > > > + work |= (1 << 7);
> > > > + v4l2_dbg(1, debug, sd, "set R_13 adc_lsb: 0x%x\n", work);
> > > > + saa711x_write(sd, R_13_RT_X_PORT_OUT_CNTL, work);
> > > > + }
> > > > +}
> > > >
> > > > /**
> > > > * saa711x_detect_chip - Detects the saa711x (or clone) variant
> > > > @@ -1782,7 +1866,10 @@ static int saa711x_probe(struct i2c_client *client,
> > > > break;
> > > > case V4L2_IDENT_GM7113C:
> > > > case V4L2_IDENT_SAA7113:
> > > > - saa711x_writeregs(sd, saa7113_init);
> > > > + if (client->dev.platform_data)
> > > > + saa711x_writeregs(sd, saa7113_datasheet_init);
> > > > + else
> > > > + saa711x_writeregs(sd, saa7113_init);
> > > > break;
> > > > default:
> > > > state->crystal_freq = SAA7115_FREQ_32_11_MHZ;
> > > > @@ -1790,6 +1877,10 @@ static int saa711x_probe(struct i2c_client *client,
> > > > }
> > > > if (state->ident > V4L2_IDENT_SAA7111A)
> > > > saa711x_writeregs(sd, saa7115_init_misc);
> > > > +
> > > > + if (client->dev.platform_data)
> > > > + saa711x_write_platform_data(state, client->dev.platform_data);
> > > > +
> > > > saa711x_set_v4lstd(sd, V4L2_STD_NTSC);
> > > > v4l2_ctrl_handler_setup(hdl);
> > > >
> > > > diff --git a/drivers/media/i2c/saa711x_regs.h b/drivers/media/i2c/saa711x_regs.h
> > > > index 4e5f2eb..57918fe 100644
> > > > --- a/drivers/media/i2c/saa711x_regs.h
> > > > +++ b/drivers/media/i2c/saa711x_regs.h
> > > > @@ -201,6 +201,14 @@
> > > > #define R_FB_PULSE_C_POS_MSB 0xfb
> > > > #define R_FF_S_PLL_MAX_PHASE_ERR_THRESH_NUM_LINES 0xff
> > > >
> > > > +/* SAA7113 bit-masks */
> > > > +#define SAA7113_R_08_HTC_MASK (0x3 << 3)
> > > > +#define SAA7113_R_10_VRLN_MASK (0x1 << 3)
> > > > +#define SAA7113_R_10_OFTS_MASK (0x3 << 6)
> > > > +#define SAA7113_R_12_RTS0_MASK (0xf << 0)
> > > > +#define SAA7113_R_12_RTS1_MASK (0xf << 4)
> > > > +#define SAA7113_R_13_ADLSB_MASK (0x1 << 7)
> > > > +
> > > > #if 0
> > > > /* Those structs will be used in the future for debug purposes */
> > > > struct saa711x_reg_descr {
> > > > diff --git a/include/media/saa7115.h b/include/media/saa7115.h
> > > > index 4079186..d7e1f5a 100644
> > > > --- a/include/media/saa7115.h
> > > > +++ b/include/media/saa7115.h
> > > > @@ -64,5 +64,44 @@
> > > > #define SAA7115_FREQ_FL_APLL (1 << 2) /* SA 3A[3], APLL, SAA7114/5 only */
> > > > #define SAA7115_FREQ_FL_DOUBLE_ASCLK (1 << 3) /* SA 39, LRDIV, SAA7114/5 only */
> > > >
> > > > +enum saa7113_output_format {
> > > > + SAA7113_OFTS_STD_ITU_656 = 0x0,
> > > > + SAA7113_OFTS_VFLAG_BY_VREF = 0x1,
> > > > + SAA7113_OFTS_VFLAG_BY_DATA_TYPE = 0x2
> > > > +};
> > > > +
> > > > +enum saa7113_horizontal_time_const {
> > > > + SAA7113_HTC_TV_MODE = 0x1,
> > > > + SAA7113_HTC_VTR_MODE = 0x3,
> > > > + SAA7113_HTC_FAST_LOCKING_MODE = 0x7
> > > > +};
> > > > +
> > > > +enum saa7113_rt_signal_cntl {
> > > > + SAA7113_RTS_ADC_LSB = 0x1,
> > > > + SAA7113_RTS_GPSW,
> > > > + SAA7115_RTS_HL,
> > > > + SAA7113_RTS_VL,
> > > > + SAA7113_RTS0_DL,
> > > > + SAA7113_RTS0_PLIN,
> > > > + SAA7113_RTS0_HREF_HS,
> > > > + SAA7113_RTS0_HS,
> > > > + SAA7113_RTS0_HQ,
> > > > + SAA7113_RTS0_ODD,
> > > > + SAA7113_RTS0_VS,
> > > > + SAA7113_RTS0_V123,
> > > > + SAA7113_RTS0_VGATE,
> > > > + SAA7113_RTS0_VREF,
> > > > + SAA7113_RTS0_FID
> > > > +};
> > > > +
> > > > +struct saa7115_platform_data {
> > > > + bool vref_len;
> > > > + bool adc_lsb;
> > > > + enum saa7113_output_format output_format;
> > > > + enum saa7113_horizontal_time_const horizontal_time_const;
> > > > + enum saa7113_rt_signal_cntl rt_signal0;
> > > > + enum saa7113_rt_signal_cntl rt_signal1;
> > > > +};
> > >
> > > Please add comments to the various enums and the struct. It should at least
> > > refer to the relevant registers in the datasheet and what the default is if
> > > no pdata is supplied. It is also important to mention which fields are
> > > saa7113 specific, and which are more generic.
> > >
> >
> > Ok, will do.
> >
> > > I also don't really like the idea of having a second initialization table.
> > > I prefer that any changes necessary are added to the platform_data. Right
> > > now specifying pdata has an unexpected side-effect of changing more than
> > > just what is set in the platform data.
> > >
> >
> > You are probably right.
> > It's just that some of the defaults in the original initialization table
> > are really strange.
> > For example R_06 which is set to 0x89 in the table, while the datasheet claims
> > this value is illegal.
> > And in register 0x08, "Horizontal time constant" is set to "VTR-mode",
> > while the datasheet clearly states that the recommended
> > value is "Fast locking mode".
>
> It would be a good idea if you can add this information as comments to those
> table entries.
>
> This table was introduced in saa7115.c in 2.6.17, but in that same kernel there
> was a saa711x.c driver which also supported saa7113, and that has correct values.
>
> I dug a bit deeper and I discovered that this table came from the em28xx-video.c
> source:
>
> http://www.linuxtv.org/hg/v4l-dvb/rev/67f47284a205
>
> Interestingly, the saa7113 table in em28xx-video.c wasn't actually used anymore
> (it was under #if 0) and the saa711x.c driver was used instead by em28xx. But
> for some reason it was this table that was used in saa7115.c instead of the one
> from saa711x.c.
>

Great discoveries :)

> The problem is that it has been in use for a long time now, and I don't know what
> might break if it is changed. That said, documenting these oddities would be a
> very good first step.
>
> Given the dubious history of the saa7113 table I think it would be a good idea
> to use a gm7113c_init[] array that uses proper defaults for the gm7113c. There
> is no need why the gm7113c should suffer the same problems as the saa7113.
>
> Even better: we can use the platform_data to select which table to use. That way
> drivers can choose which init table they want. The default should be the old
> table for saa7113 and the new table for gm7113c.
>

This sounds like a solution I would like.

I think it's cleaner if the new table is named like it's in this
patch (saa7113_datasheet_init) as the gm7113c is just a clone of the
saa7113, and the gm7113c datasheet is just a ripoff of the saa7113
datasheet.

I'll add a bool (or enum?) to the platform_data struct to toggle what
table to use. And I'll add the defaults you suggested.

I'll also try to add more documentation to the platform_data struct.

Best regards,
Jon Arne JÃrgensen

> Regards,
>
> Hans
>
> >
> > It's annoying, but I can probably work around my OCD :)
> >
> > > I know it is a lot of work, but this driver is used in many devices, so we
> > > have to be careful making changes to it.
> > >
> >
> > I do my best to only add new functions/code-paths for the gm7113c chip,
> > and not touch on the code that's already there.
> >
> > I'll spin a new patch with more comments, and I'll remove the separate
> > init table.
> >
> > And thanks again for the review.
> >
> > Best regards,
> > Jon Arne JÃrgensen
> >
> >
> > > Regards,
> > >
> > > Hans
> > >
> > > > +
> > > > #endif
> > > >
> > > >
> > > --
> > > To unsubscribe from this list: send the line "unsubscribe linux-media" in
> > > the body of a message to majordomo@xxxxxxxxxxxxxxx
> > > More majordomo info at http://vger.kernel.org/majordomo-info.html
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-media" in
> > the body of a message to majordomo@xxxxxxxxxxxxxxx
> > More majordomo info at http://vger.kernel.org/majordomo-info.html
> >
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/