On Thu, Oct 06, 2022 at 03:57:16PM +0100, Dave Stevenson wrote:
> Hi Jacopo
>
> On Wed, 5 Oct 2022 at 20:06, Jacopo Mondi <jacopo@xxxxxxxxxx> wrote:
> >
> > Change the largest visibile resolution to 2592x1944, which corresponds
> > to the active pixel array area size. Take into account the horizontal
> > and vertical limits when programming the visible sizes to skip
> > dummy/inactive pixels.
> >
> > Signed-off-by: Jacopo Mondi <jacopo@xxxxxxxxxx>
> > ---
> > drivers/media/i2c/ar0521.c | 23 +++++++++++++++++------
> > 1 file changed, 17 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/media/i2c/ar0521.c b/drivers/media/i2c/ar0521.c
> > index 581f5e42994d..2b19ba898ce8 100644
> > --- a/drivers/media/i2c/ar0521.c
> > +++ b/drivers/media/i2c/ar0521.c
> > @@ -28,10 +28,17 @@
> > #define AR0521_PIXEL_CLOCK_MIN (168 * 1000 * 1000)
> > #define AR0521_PIXEL_CLOCK_MAX (414 * 1000 * 1000)
> >
> > +#define AR0521_NATIVE_WIDTH 2604u
> > +#define AR0521_NATIVE_HEIGHT 1964u
> > +#define AR0521_MIN_X_ADDR_START 4u
> > +#define AR0521_MIN_Y_ADDR_START 4u
> > +#define AR0521_MAX_X_ADDR_END 2603u
> > +#define AR0521_MAX_Y_ADDR_END 1963u
>
> The register list I have (downloaded from OnSemi today) states that
> y_addr_max is 0x07a3, or 1955, readable from register 0x1186.
And it also states, in the documentation of y_addr_start, that legal
values are [0, 2463]. Who do we trust ? :-) [0, 2463] sounds like a copy
& paste mistake to me. Another data point is from the developer guide,
which states on the first page that the maximum values for x_addr_start
and y_addr_start are 2603 and 1963 respectively. 2603 matches the
documentation of x_addr_max.
It would be useful to dump the limits registers (0x1000 - 0x1300).
> Otherwise this looks reasonable.
>
> > +
> > #define AR0521_WIDTH_MIN 8u
> > -#define AR0521_WIDTH_MAX 2608u
> > +#define AR0521_WIDTH_MAX 2592u
> > #define AR0521_HEIGHT_MIN 8u
> > -#define AR0521_HEIGHT_MAX 1958u
> > +#define AR0521_HEIGHT_MAX 1944u
> >
> > #define AR0521_WIDTH_BLANKING_MIN 572u
> > #define AR0521_HEIGHT_BLANKING_MIN 38u /* must be even */
> > @@ -208,13 +215,17 @@ static int ar0521_read_reg(struct ar0521_dev *sensor, u16 reg, u16 *val)
> >
> > static int ar0521_set_geometry(struct ar0521_dev *sensor)
> > {
> > + /* Center the image in the visible ouput window. */
> > + u16 x = clamp((AR0521_WIDTH_MAX - sensor->fmt.width) / 2,
> > + AR0521_MIN_X_ADDR_START, AR0521_MAX_X_ADDR_END);
> > + u16 y = clamp(((AR0521_HEIGHT_MAX - sensor->fmt.height) / 2) & ~1,
> > + AR0521_MIN_Y_ADDR_START, AR0521_MAX_Y_ADDR_END);
> > +
> > /* All dimensions are unsigned 12-bit integers */
> > - u16 x = (AR0521_WIDTH_MAX - sensor->fmt.width) / 2;
> > - u16 y = ((AR0521_HEIGHT_MAX - sensor->fmt.height) / 2) & ~1;
> > __be16 regs[] = {
> > be(AR0521_REG_FRAME_LENGTH_LINES),
> > - be(sensor->total_height),
> > - be(sensor->total_width),
> > + be(sensor->fmt.height + sensor->ctrls.vblank->val),
> > + be(sensor->fmt.width + sensor->ctrls.hblank->val),
> > be(x),
> > be(y),
> > be(x + sensor->fmt.width - 1),
--
Regards,
Laurent Pinchart
