Re: [PATCH RESEND v10 5/5] media: i2c: imx334: update pixel and link frequency

From: Sakari Ailus
Date: Wed Jan 25 2023 - 04:42:37 EST

Hi Shravan,

On Tue, Jan 24, 2023 at 05:34:02AM +0000, Shravan.Chippa@xxxxxxxxxxxxx wrote:
> Hi Sakari,
>
> > -----Original Message-----
> > From: Sakari Ailus <sakari.ailus@xxxxxx>
> > Sent: 24 January 2023 04:33 AM
> > To: shravan Chippa - I35088 <Shravan.Chippa@xxxxxxxxxxxxx>
> > Cc: paul.j.murphy@xxxxxxxxx; daniele.alessandrelli@xxxxxxxxx;
> > mchehab@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
> > shawnguo@xxxxxxxxxx; s.hauer@xxxxxxxxxxxxxx; festevam@xxxxxxxxx;
> > kernel@xxxxxxxxxxxxxx; linux-imx@xxxxxxx; linux-media@xxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux-arm-
> > kernel@xxxxxxxxxxxxxxxxxxx
> > Subject: Re: [PATCH RESEND v10 5/5] media: i2c: imx334: update pixel and link
> > frequency
> >
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the
> > content is safe
> >
> > Hi Shravan,
> >
> > On Sat, Jan 21, 2023 at 09:07:13AM +0530, shravan kumar wrote:
> > > From: Shravan Chippa <shravan.chippa@xxxxxxxxxxxxx>
> > >
> > > Update pixel_rate and link frequency for 1920x1080@30 while changing
> > > mode.
> > >
> > > Add dummy ctrl cases for pixel_rate and link frequency to avoid error
> > > while changing the modes dynamically.
> > >
> > > Add support to handle multiple link frequencies.
> > >
> > > Suggested-by: Sakari Ailus <sakari.ailus@xxxxxx>
> > > Signed-off-by: Shravan Chippa <shravan.chippa@xxxxxxxxxxxxx>
> > > ---
> > > drivers/media/i2c/imx334.c | 41
> > > ++++++++++++++++++++++++++++----------
> > > 1 file changed, 30 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/imx334.c b/drivers/media/i2c/imx334.c
> > > index 309c706114d2..62b104eaa437 100644
> > > --- a/drivers/media/i2c/imx334.c
> > > +++ b/drivers/media/i2c/imx334.c
> > > @@ -49,7 +49,8 @@
> > > #define IMX334_INCLK_RATE 24000000
> > >
> > > /* CSI2 HW configuration */
> > > -#define IMX334_LINK_FREQ 891000000
> > > +#define IMX334_LINK_FREQ_891M 891000000
> > > +#define IMX334_LINK_FREQ_445M 445500000
> > > #define IMX334_NUM_DATA_LANES 4
> > >
> > > #define IMX334_REG_MIN 0x00
> > > @@ -139,12 +140,14 @@ struct imx334 {
> > > u32 vblank;
> > > const struct imx334_mode *cur_mode;
> > > struct mutex mutex;
> > > + unsigned long menu_skip_mask;
> > > u32 cur_code;
> > > bool streaming;
> > > };
> > >
> > > static const s64 link_freq[] = {
> > > - IMX334_LINK_FREQ,
> > > + IMX334_LINK_FREQ_891M,
> > > + IMX334_LINK_FREQ_445M,
> > > };
> > >
> > > /* Sensor mode registers for 1920x1080@30fps */ @@ -468,7 +471,7 @@
> > > static const struct imx334_mode supported_modes[] = {
> > > .vblank_min = 45,
> > > .vblank_max = 132840,
> > > .pclk = 297000000,
> > > - .link_freq_idx = 0,
> > > + .link_freq_idx = 1,
> > > .reg_list = {
> > > .num_of_regs = ARRAY_SIZE(mode_1920x1080_regs),
> > > .regs = mode_1920x1080_regs, @@ -598,6 +601,11
> > > @@ static int imx334_update_controls(struct imx334 *imx334,
> > > if (ret)
> > > return ret;
> > >
> > > + ret = __v4l2_ctrl_modify_range(imx334->pclk_ctrl, mode->pclk,
> > > + mode->pclk, 1, mode->pclk);
> > > + if (ret)
> > > + return ret;
> > > +
> > > ret = __v4l2_ctrl_modify_range(imx334->hblank_ctrl, mode->hblank,
> > > mode->hblank, 1, mode->hblank);
> > > if (ret)
> > > @@ -698,6 +706,8 @@ static int imx334_set_ctrl(struct v4l2_ctrl *ctrl)
> > > pm_runtime_put(imx334->dev);
> > >
> > > break;
> > > + case V4L2_CID_PIXEL_RATE:
> > > + case V4L2_CID_LINK_FREQ:
> > > case V4L2_CID_HBLANK:
> > > ret = 0;
> > > break;
> > > @@ -1047,7 +1057,7 @@ static int imx334_parse_hw_config(struct imx334
> > *imx334)
> > > struct fwnode_handle *ep;
> > > unsigned long rate;
> > > int ret;
> > > - int i;
> > > + int i, j;
> >
> > unsigned int would be nicer.
> I will change.
> >
> > >
> > > if (!fwnode)
> > > return -ENXIO;
> > > @@ -1097,11 +1107,20 @@ static int imx334_parse_hw_config(struct imx334
> > *imx334)
> > > goto done_endpoint_free;
> > > }
> > >
> > > - for (i = 0; i < bus_cfg.nr_of_link_frequencies; i++)
> > > - if (bus_cfg.link_frequencies[i] == IMX334_LINK_FREQ)
> > > + for (i = 0; i < bus_cfg.nr_of_link_frequencies; i++) {
> > > + for (j = 0; j < ARRAY_SIZE(link_freq); j++) {
> > > + if (bus_cfg.link_frequencies[i] == link_freq[j]) {
> > > + set_bit(j, &imx334->menu_skip_mask);
> >
> > Is there a guarantee that you'll only be using the modes with the listed
> > frequencies? I don't see one but I might have missed it.
>
> If I understand it correctly, the question here is, the listed
> freqeunceis and modes are one to one mapped? Then yes.

I don't see this being checked in imx334_set_pad_format(), for instance.

If a frequency isn't in DT, the driver isn't supposed to be using it
either.

>
> Thanks.
> shravan
> >
> > > + break;
> > > + }
> > > + }
> > > +
> > > + if (j == ARRAY_SIZE(link_freq)) {
> > > + ret = dev_err_probe(imx334->dev, -EINVAL,
> > > + "no supported link freq
> > > + found\n");
> > > goto done_endpoint_free;
> > > -
> > > - ret = -EINVAL;
> > > + }
> > > + }
> > >
> > > done_endpoint_free:
> > > v4l2_fwnode_endpoint_free(&bus_cfg);
> > > @@ -1232,10 +1251,10 @@ static int imx334_init_controls(struct imx334
> > *imx334)
> > > imx334->link_freq_ctrl = v4l2_ctrl_new_int_menu(ctrl_hdlr,
> > > &imx334_ctrl_ops,
> > > V4L2_CID_LINK_FREQ,
> > > - ARRAY_SIZE(link_freq) -
> > > - 1,
> > > - mode->link_freq_idx,
> > > + __fls(imx334->menu_skip_mask),
> > > +
> > > + __ffs(imx334->menu_skip_mask),
> > > link_freq);
> > > +
> > > if (imx334->link_freq_ctrl)
> > > imx334->link_freq_ctrl->flags |=
> > > V4L2_CTRL_FLAG_READ_ONLY;

--
Kind regards,

Sakari Ailus