Hi Sakari,
On Friday, October 18, 2019 8:54:19 P.M. CEST Sakari Ailus wrote:
> Hi Janusz,
>
> On Sun, Oct 13, 2019 at 02:50:50PM +0200, Janusz Krzysztofik wrote:
> > A hardcoded 12 MHz master clock frequency has been assumed since
> > conversion of the driver from soc_camera sensor to a standalone V4L2
> > subdevice by commit 23a52386fabe ("media: ov6650: convert to standalone
> > v4l2 subdevice"). Fix it.
> >
> > Define a static table of supported master clock rates (fix misnamed
> > symbol while being at it), then use v4l2_clk_get/set_rate() to obtain
> > a clock rate matching one of those supported. On success, apply
> > respective master clock hardware divisor provided by the matching
> > element of the table.
> >
> > Signed-off-by: Janusz Krzysztofik <[email protected]>
> > ---
> > drivers/media/i2c/ov6650.c | 64 ++++++++++++++++++++++++++++++++++----
> > 1 file changed, 58 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/media/i2c/ov6650.c b/drivers/media/i2c/ov6650.c
> > index f4723c0b5c70..13fd7c4699b2 100644
> > --- a/drivers/media/i2c/ov6650.c
> > +++ b/drivers/media/i2c/ov6650.c
> > @@ -124,7 +124,7 @@
> >
> > #define DEF_AECH 0x4D
> >
> > -#define CLKRC_6MHz 0x00
> > +#define CLKRC_8MHz 0x00
> > #define CLKRC_12MHz 0x40
> > #define CLKRC_16MHz 0x80
> > #define CLKRC_24MHz 0xc0
> > @@ -201,6 +201,29 @@ struct ov6650 {
> > u32 code;
> > };
> >
> > +struct ov6650_xclk {
> > + unsigned long rate;
> > + u8 clkrc;
> > +};
> > +
> > +static const struct ov6650_xclk ov6650_xclk[] = {
> > +{
> > + .rate = 8000000,
> > + .clkrc = CLKRC_8MHz,
> > +},
> > +{
> > + .rate = 12000000,
> > + .clkrc = CLKRC_12MHz,
> > +},
> > +{
> > + .rate = 16000000,
> > + .clkrc = CLKRC_16MHz,
> > +},
> > +{
> > + .rate = 24000000,
> > + .clkrc = CLKRC_24MHz,
> > +},
> > +};
> >
> > static u32 ov6650_codes[] = {
> > MEDIA_BUS_FMT_YUYV8_2X8,
> > @@ -774,7 +797,7 @@ static int ov6650_reset(struct i2c_client *client)
> > }
> >
> > /* program default register values */
> > -static int ov6650_prog_dflt(struct i2c_client *client)
> > +static int ov6650_prog_dflt(struct i2c_client *client, u8 clkrc)
> > {
> > int ret;
> >
> > @@ -782,7 +805,7 @@ static int ov6650_prog_dflt(struct i2c_client *client)
> >
> > ret = ov6650_reg_write(client, REG_COMA, 0); /* ~COMA_RESET */
> > if (!ret)
> > - ret = ov6650_reg_write(client, REG_CLKRC, CLKRC_12MHz);
> > + ret = ov6650_reg_write(client, REG_CLKRC, clkrc);
> > if (!ret)
> > ret = ov6650_reg_rmw(client, REG_COMB, 0, COMB_BAND_FILTER);
> >
> > @@ -793,8 +816,10 @@ static int ov6650_video_probe(struct v4l2_subdev *sd)
> > {
> > struct i2c_client *client = v4l2_get_subdevdata(sd);
> > struct ov6650 *priv = to_ov6650(client);
> > - u8 pidh, pidl, midh, midl;
> > - int ret;
> > + const struct ov6650_xclk *xclk;
> > + unsigned long rate;
> > + u8 pidh, pidl, midh, midl;
> > + int i, ret;
> >
> > priv->clk = v4l2_clk_get(&client->dev, NULL);
> > if (IS_ERR(priv->clk)) {
> > @@ -803,6 +828,33 @@ static int ov6650_video_probe(struct v4l2_subdev *sd)
> > return ret;
> > }
> >
> > + rate = v4l2_clk_get_rate(priv->clk);
> > + for (i = 0; rate && i < ARRAY_SIZE(ov6650_xclk); i++) {
> > + if (rate != ov6650_xclk[i].rate)
> > + continue;
> > +
> > + xclk = &ov6650_xclk[i];
> > + dev_info(&client->dev, "using host default clock rate %lukHz\n",
> > + rate / 1000);
> > + break;
> > + }
>
> xclk is undefined unless it was set in the previous loop.
Indeed, sorry for that.
> Please initialise
> to to NULL. I can fix that, too, while applying the patch.
OK, please do if you can.
Thanks,
Janusz
> > + for (i = 0; !xclk && i < ARRAY_SIZE(ov6650_xclk); i++) {
> > + ret = v4l2_clk_set_rate(priv->clk, ov6650_xclk[i].rate);
> > + if (ret || v4l2_clk_get_rate(priv->clk) != ov6650_xclk[i].rate)
> > + continue;
> > +
> > + xclk = &ov6650_xclk[i];
> > + dev_info(&client->dev, "using negotiated clock rate %lukHz\n",
> > + xclk->rate / 1000);
> > + break;
> > + }
> > + if (!xclk) {
> > + dev_err(&client->dev, "unable to get supported clock rate\n");
> > + if (!ret)
> > + ret = -EINVAL;
> > + goto eclkput;
> > + }
> > +
> > ret = ov6650_s_power(sd, 1);
> > if (ret < 0)
> > goto eclkput;
> > @@ -836,7 +888,7 @@ static int ov6650_video_probe(struct v4l2_subdev *sd)
> >
> > ret = ov6650_reset(client);
> > if (!ret)
> > - ret = ov6650_prog_dflt(client);
> > + ret = ov6650_prog_dflt(client, xclk->clkrc);
> > if (!ret) {
> > struct v4l2_mbus_framefmt mf = ov6650_def_fmt;
> >
>
>
