| Message ID | 20180323163453.96495-2-swboyd@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Fri, Mar 23, 2018 at 09:34:49AM -0700, Stephen Boyd wrote: > From: Stephen Boyd <sboyd@codeaurora.org> > > Some qcom platforms make some GPIOs or pins unavailable for use > by non-secure operating systems, and thus reading or writing the > registers for those pins will cause access control issues. > Introduce a DT property to describe the set of GPIOs that are > available for use so that higher level OSes are able to know what > pins to avoid reading/writing. > > Cc: Grant Likely <grant.likely@secretlab.ca> > Cc: <devicetree@vger.kernel.org> > Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> > Signed-off-by: Stephen Boyd <swboyd@chromium.org> > --- > Documentation/devicetree/bindings/gpio/gpio.txt | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) Reviewed-by: Rob Herring <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt index b5de08e3b1a2..a7c31de29362 100644 --- a/Documentation/devicetree/bindings/gpio/gpio.txt +++ b/Documentation/devicetree/bindings/gpio/gpio.txt @@ -151,9 +151,9 @@ in a lot of designs, some using all 32 bits, some using 18 and some using first 18 GPIOs, at local offset 0 .. 17, are in use. If these GPIOs do not happen to be the first N GPIOs at offset 0...N-1, an -additional bitmask is needed to specify which GPIOs are actually in use, -and which are dummies. The bindings for this case has not yet been -specified, but should be specified if/when such hardware appears. +additional set of tuples is needed to specify which GPIOs are unusable, with +the gpio-reserved-ranges binding. This property indicates the start and size +of the GPIOs that can't be used. Optionally, a GPIO controller may have a "gpio-line-names" property. This is an array of strings defining the names of the GPIO lines going out of the @@ -178,6 +178,7 @@ gpio-controller@00000000 { gpio-controller; #gpio-cells = <2>; ngpios = <18>; + gpio-reserved-ranges = <0 4>, <12 2>; gpio-line-names = "MMC-CD", "MMC-WP", "VDD eth", "RST eth", "LED R", "LED G", "LED B", "Col A", "Col B", "Col C", "Col D", "Row A", "Row B", "Row C", "Row D", "NMI button",