Hej Sakari,
Tack för feedback.
On 2024-08-27 13:32:43 +0000, Sakari Ailus wrote:
> Hejssan,
>
> Tack för lappan!
>
> On Tue, Aug 27, 2024 at 03:18:41PM +0200, Niklas Söderlund wrote:
> > The MAX96724 is almost identical to the MAX96712 and can be supported by
> > the same driver, add support for it.
> >
> > For the staging driver which only supports patter generation the big
> > difference is that the datasheet (rev 4) for MAX96724 do not describe
> > the DEBUG_EXTRA register, which is at offset 0x0009 on MAX96712. It's
> > not clear if this register is removed or moved to a different offset.
> > What is known is writing to register 0x0009 have no effect on MAX96724.
> >
> > This makes it impossible to increase the test pattern clock frequency
> > from 25 MHz to 75Mhz on MAX96724. To be able to get a stable test
> > pattern the DPLL frequency have to be increase instead to compensate for
> > this. The frequency selected is found by experimentation as the MAX96724
> > datasheet is much sparser then what's available for MAX96712.
> >
> > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> > ---
> > * Changes since v1
> > - Group in series together with binding.
> > ---
> > drivers/staging/media/max96712/max96712.c | 26 ++++++++++++++++++-----
> > 1 file changed, 21 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/staging/media/max96712/max96712.c b/drivers/staging/media/max96712/max96712.c
> > index 6bdbccbee05a..6bd02276c413 100644
> > --- a/drivers/staging/media/max96712/max96712.c
> > +++ b/drivers/staging/media/max96712/max96712.c
> > @@ -17,8 +17,10 @@
> > #include <media/v4l2-subdev.h>
> >
> > #define MAX96712_ID 0x20
> > +#define MAX96724_ID 0xA7
> >
> > #define MAX96712_DPLL_FREQ 1000
> > +#define MAX96724_DPLL_FREQ 1200
> >
> > enum max96712_pattern {
> > MAX96712_PATTERN_CHECKERBOARD = 0,
> > @@ -31,6 +33,7 @@ struct max96712_priv {
> > struct gpio_desc *gpiod_pwdn;
> >
> > bool cphy;
> > + bool max96724;
> > struct v4l2_mbus_config_mipi_csi2 mipi;
> >
> > struct v4l2_subdev sd;
> > @@ -120,6 +123,7 @@ static void max96712_mipi_enable(struct max96712_priv *priv, bool enable)
> >
> > static void max96712_mipi_configure(struct max96712_priv *priv)
> > {
> > + unsigned int dpll_freq;
> > unsigned int i;
> > u8 phy5 = 0;
> >
> > @@ -152,10 +156,11 @@ static void max96712_mipi_configure(struct max96712_priv *priv)
> > max96712_write(priv, 0x8a5, phy5);
> >
> > /* Set link frequency for PHY0 and PHY1. */
> > + dpll_freq = priv->max96724 ? MAX96724_DPLL_FREQ : MAX96712_DPLL_FREQ;
> > max96712_update_bits(priv, 0x415, 0x3f,
> > - ((MAX96712_DPLL_FREQ / 100) & 0x1f) | BIT(5));
> > + ((dpll_freq / 100) & 0x1f) | BIT(5));
> > max96712_update_bits(priv, 0x418, 0x3f,
> > - ((MAX96712_DPLL_FREQ / 100) & 0x1f) | BIT(5));
> > + ((dpll_freq / 100) & 0x1f) | BIT(5));
> >
> > /* Enable PHY0 and PHY1 */
> > max96712_update_bits(priv, 0x8a2, 0xf0, 0x30);
> > @@ -181,7 +186,8 @@ static void max96712_pattern_enable(struct max96712_priv *priv, bool enable)
> > }
> >
> > /* PCLK 75MHz. */
> > - max96712_write(priv, 0x0009, 0x01);
> > + if (!priv->max96724)
> > + max96712_write(priv, 0x0009, 0x01);
>
> It'd be nice to have a macro for this, espeically now that the driver
> supports more than one chip.
What do you mean by macro? To test for priv->max96724, a define for the
register name or something else?
>
> >
> > /* Configure Video Timing Generator for 1920x1080 @ 30 fps. */
> > max96712_write_bulk_value(priv, 0x1052, 0, 3);
> > @@ -303,6 +309,7 @@ static const struct v4l2_ctrl_ops max96712_ctrl_ops = {
> >
> > static int max96712_v4l2_register(struct max96712_priv *priv)
> > {
> > + unsigned int dpll_freq;
> > long pixel_rate;
> > int ret;
> >
> > @@ -317,7 +324,8 @@ static int max96712_v4l2_register(struct max96712_priv *priv)
> > * TODO: Once V4L2_CID_LINK_FREQ is changed from a menu control to an
> > * INT64 control it should be used here instead of V4L2_CID_PIXEL_RATE.
> > */
> > - pixel_rate = MAX96712_DPLL_FREQ / priv->mipi.num_data_lanes * 1000000;
> > + dpll_freq = priv->max96724 ? MAX96724_DPLL_FREQ : MAX96712_DPLL_FREQ;
> > + pixel_rate = dpll_freq / priv->mipi.num_data_lanes * 1000000;
> > v4l2_ctrl_new_std(&priv->ctrl_handler, NULL, V4L2_CID_PIXEL_RATE,
> > pixel_rate, pixel_rate, 1, pixel_rate);
> >
> > @@ -438,8 +446,15 @@ static int max96712_probe(struct i2c_client *client)
> > if (priv->gpiod_pwdn)
> > usleep_range(4000, 5000);
> >
> > - if (max96712_read(priv, 0x4a) != MAX96712_ID)
> > + switch (max96712_read(priv, 0x4a)) {
> > + case MAX96712_ID:
> > + break;
> > + case MAX96724_ID:
> > + priv->max96724 = true;
> > + break;
> > + default:
> > return -ENODEV;
> > + }
> >
> > max96712_reset(priv);
> >
> > @@ -463,6 +478,7 @@ static void max96712_remove(struct i2c_client *client)
> >
> > static const struct of_device_id max96712_of_table[] = {
> > { .compatible = "maxim,max96712" },
> > + { .compatible = "maxim,max96724" },
>
> How about adding compatible specific data to convey the model, instead of a
> switch? See e.g. drivers/media/i2c/ccs/ccs-core.c for an example.
>
> You could store the DPLL frequency there, too.
Good idea, will do so in next version.
>
> > { /* sentinel */ },
> > };
> > MODULE_DEVICE_TABLE(of, max96712_of_table);
> >
>
> --
> Trevliga hälsningar,
>
> Sakari Ailus
--
Kind Regards,
Niklas Söderlund
