| Message ID | 1427802195-221906-1-git-send-email-mika.westerberg@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
On 3/31/15, 4:43 AM, "Mika Westerberg" <mika.westerberg@linux.intel.com> wrote: >With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name >functions just like Device Tree is doing. Make sure that the documentation >mentions _DSD as the recommended way to describe GPIOs in ACPI systems. > >Reported-by: Darren Hart <dvhart@linux.intel.com> >Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Thanks Mika! Couple of nits below to help it read a little better. >--- > Documentation/gpio/board.txt | 41 >+++++++++++++++++++++++++++++++++++++---- > 1 file changed, 37 insertions(+), 4 deletions(-) > >diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt >index 8b35f51fe7b6..b68cfa8a6865 100644 >--- a/Documentation/gpio/board.txt >+++ b/Documentation/gpio/board.txt >@@ -50,10 +50,43 @@ gpiod_is_active_low(power) will be true). > > ACPI > ---- >-ACPI does not support function names for GPIOs. Therefore, only the "idx" >-argument of gpiod_get_index() is useful to discriminate between GPIOs >assigned >-to a device. The "con_id" argument can still be set for debugging >purposes (it >-will appear under error messages as well as debug and sysfs nodes). >+ACPI does also support function names for GPIOs in similar fashion than >DT. ACPI also supports function names for GPIOs in a similar fashion to DT. >+The above DT example can be converted to corresponding ACPI version with ... to an equivalent ACPI description with >+the help of _DSD (Device Specific Data) which was introduced in ACPI 5.1: s/ which was/, / -- Darren >+ >+ Device (FOO) { >+ Name (_CRS, ResourceTemplate () { >+ GpioIo (Exclusive, ..., IoRestrictionOutputOnly, >+ "\\_SB.GPI0") {15} // red >+ GpioIo (Exclusive, ..., IoRestrictionOutputOnly, >+ "\\_SB.GPI0") {16} // green >+ GpioIo (Exclusive, ..., IoRestrictionOutputOnly, >+ "\\_SB.GPI0") {17} // blue >+ GpioIo (Exclusive, ..., IoRestrictionOutputOnly, >+ "\\_SB.GPI0") {1} // power >+ }) >+ >+ Name (_DSD, Package () { >+ ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), >+ Package () { >+ Package () { >+ "led-gpios", >+ Package () { >+ ^FOO, 0, 0, 1, >+ ^FOO, 1, 0, 1, >+ ^FOO, 2, 0, 1, >+ } >+ }, >+ Package () { >+ "power-gpios", >+ Package () {^FOO, 3, 0, 0}, >+ }, >+ } >+ }) >+ } >+ >+For more information about the ACPI GPIO bindings see >+Documentation/acpi/gpio-properties.txt. > > Platform Data > ------------- >-- >2.1.4 > >
diff --git a/Documentation/gpio/board.txt b/Documentation/gpio/board.txt index 8b35f51fe7b6..b68cfa8a6865 100644 --- a/Documentation/gpio/board.txt +++ b/Documentation/gpio/board.txt @@ -50,10 +50,43 @@ gpiod_is_active_low(power) will be true). ACPI ---- -ACPI does not support function names for GPIOs. Therefore, only the "idx" -argument of gpiod_get_index() is useful to discriminate between GPIOs assigned -to a device. The "con_id" argument can still be set for debugging purposes (it -will appear under error messages as well as debug and sysfs nodes). +ACPI does also support function names for GPIOs in similar fashion than DT. +The above DT example can be converted to corresponding ACPI version with +the help of _DSD (Device Specific Data) which was introduced in ACPI 5.1: + + Device (FOO) { + Name (_CRS, ResourceTemplate () { + GpioIo (Exclusive, ..., IoRestrictionOutputOnly, + "\\_SB.GPI0") {15} // red + GpioIo (Exclusive, ..., IoRestrictionOutputOnly, + "\\_SB.GPI0") {16} // green + GpioIo (Exclusive, ..., IoRestrictionOutputOnly, + "\\_SB.GPI0") {17} // blue + GpioIo (Exclusive, ..., IoRestrictionOutputOnly, + "\\_SB.GPI0") {1} // power + }) + + Name (_DSD, Package () { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () { + "led-gpios", + Package () { + ^FOO, 0, 0, 1, + ^FOO, 1, 0, 1, + ^FOO, 2, 0, 1, + } + }, + Package () { + "power-gpios", + Package () {^FOO, 3, 0, 0}, + }, + } + }) + } + +For more information about the ACPI GPIO bindings see +Documentation/acpi/gpio-properties.txt. Platform Data -------------
With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name functions just like Device Tree is doing. Make sure that the documentation mentions _DSD as the recommended way to describe GPIOs in ACPI systems. Reported-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> --- Documentation/gpio/board.txt | 41 +++++++++++++++++++++++++++++++++++++---- 1 file changed, 37 insertions(+), 4 deletions(-)