[PATCH v2 3/5] ARM: bcm2835: add rpi power domain driver
khilman at kernel.org
Mon Dec 7 15:35:10 PST 2015
Eric Anholt <eric at anholt.net> writes:
> From: Alexander Aring <alex.aring at gmail.com>
> This patch adds support for several power domains on Raspberry Pi,
> including USB (so it can be enabled even if the bootloader didn't do
> it), and graphics.
> This patch is the combined work of Eric Anholt (who wrote USB support
> inside of the Raspberry Pi firmware driver, and wrote the non-USB
> domain support) and Alexander Aring (who separated the original USB
> work out from the firmware driver).
> Signed-off-by: Alexander Aring <alex.aring at gmail.com>
> Signed-off-by: Eric Anholt <eric at anholt.net>
> v2: Add support for power domains other than USB, using the new
> firmware interface, reword commit message (changes by Eric)
> + * Firmware indices for the old power domains interface. Only a few
> + * of them were actually implemented.
> + */
> +#define RPI_OLD_POWER_DOMAIN_USB 3
> +#define RPI_OLD_POWER_DOMAIN_V3D 10
Is "old" the right word here? Are there firmware versions that could be
used instead? What happens when the firwmware is updated next time?
> + /*
> + * Use the old firmware interface for USB power, so that we
> + * can turn it on even if the firmware hasn't been updated.
> + */
> + rpi_init_old_power_domain(rpi_domains, RPI_POWER_DOMAIN_USB,
> + RPI_OLD_POWER_DOMAIN_USB, "USB");
This seems a bit restrictive.
To me, it seems that determining "old" or "new" (or revision of fw
interface to use) should be described in DT, not hard-coded in the power
What about an additional DT property to describe that? or possibly
another cell in the domain which could be used to optionally set
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