media: ov5640: Adjust the clock based on the expected rate

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The clock structure for the PCLK is quite obscure in the documentation, and
was hardcoded through the bytes array of each and every mode.

This is troublesome, since we cannot adjust it at runtime based on other
parameters (such as the number of bytes per pixel), and we can't support
either framerates that have not been used by the various vendors, since we
don't have the needed initialization sequence.

We can however understand how the clock tree works, and then implement some
functions to derive the various parameters from a given rate. And now that
those parameters are calculated at runtime, we can remove them from the
initialization sequence.

The modes also gained a new parameter which is the clock that they are
running at, from the register writes they were doing, so for now the switch
to the new algorithm should be transparent.

Co-Developed-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Tested-by: Adam Ford <aford173@gmail.com> #imx6dq
Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

...

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Maxime Ripard 2018-12-03 03:44:17 -05:00 • committed by Mauro Carvalho Chehab

parent 0711544991

commit aa2882481c

1 changed files with 364 additions and 1 deletions

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drivers/media/i2c/ov5640.c

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