[PATCH v4 04/12] thermal: armada: Clarify control registers accesses
Baruch Siach
baruch at tkos.co.il
Mon Dec 18 12:35:42 PST 2017
Hi Miquèl,
On Mon, Dec 18, 2017 at 03:36:35PM +0100, Miquel Raynal wrote:
> Bindings were incomplete for a long time by only exposing one of the two
> available control registers. To ease the migration to the full bindings
> (already in use for the Armada 375 SoC), rename the pointers for
> clarification. This way, it will only be needed to add another pointer
> to access the other control register when the time comes.
>
> This avoids dangerous situations where the offset 0 of the control
> area can be either one register or the other depending on the bindings
> used. After this change, device trees of other SoCs could be migrated to
> the "full" bindings if they may benefit from features from the
> unaccessible register, without any change in the driver.
>
> Signed-off-by: Miquel Raynal <miquel.raynal at free-electrons.com>
> Reviewed-by: Gregory CLEMENT <gregory.clement at free-electrons.com>
> ---
[...]
> + /*
> + * Legacy DT bindings only described "control1" register (also referred
> + * as "control MSB" on old documentation). New bindings cover
> + * "control0/control LSB" and "control1/control MSB" registers within
> + * the same resource, which is then of size 8 instead of 4.
> + */
> + if (resource_size(res) == LEGACY_CONTROL_MEM_LEN) {
> + /* ->control0 unavailable in this configuration */
> + priv->control1 = control + LEGACY_CONTROL1_OFFSET;
> + } else {
> + priv->control0 = control + CONTROL0_OFFSET;
> + priv->control1 = control + CONTROL1_OFFSET;
> + }
The needs_control0 field that you mentioned in the cover page is missing here.
baruch
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