aboutsummaryrefslogtreecommitdiff
path: root/Documentation
diff options
context:
space:
mode:
authorArnd Bergmann <arnd@arndb.de>2013-05-06 23:49:09 +0200
committerArnd Bergmann <arnd@arndb.de>2013-05-06 23:49:09 +0200
commit241a9871263f3114717c0ed416a1bd1d2415d1fb (patch)
treec41f73f7c38ae2120c3507cd2d487eeed160472a /Documentation
parent2254c36ddeb87d4975d2e4709413dd275a913e83 (diff)
parent0682edaaa32c778ad2efac73fe3c8d9309e35991 (diff)
downloadlinux-linaro-stable-241a9871263f3114717c0ed416a1bd1d2415d1fb.tar.gz
Merge branch 'exynos/pwm-clocksource' into late/multiplatform
This series from Tomasz Figa restores support for the pwm clocksource in Exynos, which was broken during the conversion of the platform to the common clk framework. The clocksource is only used in one board in the mainline kernel (universal_c210), and this makes it work for DT based probing as well as restoring the non-DT based case. * exynos/pwm-clocksource: ARM: dts: exynops4210: really add universal_c210 dts ARM: dts: exynos4210: Add basic dts file for universal_c210 board ARM: dts: exynos4: Add node for PWM device ARM: SAMSUNG: Do not register legacy timer interrupts on Exynos clocksource: samsung_pwm_timer: Work around rounding errors in clockevents core clocksource: samsung_pwm_timer: Correct programming of clock events clocksource: samsung_pwm_timer: Use proper clockevents max_delta clocksource: samsung_pwm_timer: Add support for non-DT platforms clocksource: samsung_pwm_timer: Drop unused samsung_pwm struct clocksource: samsung_pwm_timer: Keep all driver data in a structure clocksource: samsung_pwm_timer: Make PWM spinlock global clocksource: samsung_pwm_timer: Let platforms select the driver Documentation: Add device tree bindings for Samsung PWM timers clocksource: add samsung pwm timer driver Conflicts: arch/arm/boot/dts/Makefile arch/arm/mach-exynos/common.c drivers/clocksource/Kconfig drivers/clocksource/Makefile Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-samsung.txt43
1 files changed, 43 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/pwm/pwm-samsung.txt b/Documentation/devicetree/bindings/pwm/pwm-samsung.txt
new file mode 100644
index 000000000000..ac67c687a327
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-samsung.txt
@@ -0,0 +1,43 @@
+* Samsung PWM timers
+
+Samsung SoCs contain PWM timer blocks which can be used for system clock source
+and clock event timers, as well as to drive SoC outputs with PWM signal. Each
+PWM timer block provides 5 PWM channels (not all of them can drive physical
+outputs - see SoC and board manual).
+
+Be aware that the clocksource driver supports only uniprocessor systems.
+
+Required properties:
+- compatible : should be one of following:
+ samsung,s3c2410-pwm - for 16-bit timers present on S3C24xx SoCs
+ samsung,s3c6400-pwm - for 32-bit timers present on S3C64xx SoCs
+ samsung,s5p6440-pwm - for 32-bit timers present on S5P64x0 SoCs
+ samsung,s5pc100-pwm - for 32-bit timers present on S5PC100, S5PV210,
+ Exynos4210 rev0 SoCs
+ samsung,exynos4210-pwm - for 32-bit timers present on Exynos4210,
+ Exynos4x12 and Exynos5250 SoCs
+- reg: base address and size of register area
+- interrupts: list of timer interrupts (one interrupt per timer, starting at
+ timer 0)
+- #pwm-cells: number of cells used for PWM specifier - must be 3
+ the specifier format is as follows:
+ - phandle to PWM controller node
+ - index of PWM channel (from 0 to 4)
+ - PWM signal period in nanoseconds
+ - bitmask of optional PWM flags:
+ 0x1 - invert PWM signal
+
+Optional properties:
+- samsung,pwm-outputs: list of PWM channels used as PWM outputs on particular
+ platform - an array of up to 5 elements being indices of PWM channels
+ (from 0 to 4), the order does not matter.
+
+Example:
+ pwm@7f006000 {
+ compatible = "samsung,s3c6400-pwm";
+ reg = <0x7f006000 0x1000>;
+ interrupt-parent = <&vic0>;
+ interrupts = <23>, <24>, <25>, <27>, <28>;
+ samsung,pwm-outputs = <0>, <1>;
+ #pwm-cells = <3>;
+ }