Commit Graph

5 Commits

Author SHA1 Message Date
Tomasz Figa 11ad39ede2 pwm: Add new pwm-samsung driver
This patch introduces new Samsung PWM driver, which is completely
rewritten to be multiplatform- and DeviceTree-aware.

In addition, remaining problems of old driver are fixed, such as:
 - proper handling of hardware variants,
 - synchronization on SMP systems,
 - handling of boundary parameter values,
 - hardware sharing with PWM clocksource driver,
 - undefined state of PWM output after stopping PWM channel.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Mark Brown <broonie@linaro.org>
Tested-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thierry Reding <thierry.reding@gmail.com>
2013-08-12 21:53:22 +02:00
Tomasz Figa f9bb48a2c2 clocksource: samsung_pwm_timer: Add support for non-DT platforms
This patch extends the driver to support platforms that still use legacy
ATAGS-based boot, without device tree, by providing an exported function
that can be used from platform code to initialize the clocksource.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-04-28 12:16:54 -07:00
Tomasz Figa 09d718a78c clocksource: samsung_pwm_timer: Drop unused samsung_pwm struct
This patch removes the unused samsung_pwm struct from public header.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-04-28 12:16:52 -07:00
Tomasz Figa 7aac482e62 clocksource: samsung_pwm_timer: Make PWM spinlock global
This patch makes the PWM spinlock global and exports it to allow using
it in Samsung PWM driver (will be reworked to use proper synchronization
in further patches).

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-04-28 12:16:46 -07:00
Tomasz Figa f11899894c clocksource: add samsung pwm timer driver
This adds a new clocksource driver for the PWM timer that is
present in most Samsung SoCs, based on the existing driver in
arch/arm/plat-samsung/samsung-time.c and many changes implemented by
Tomasz Figa.

Originally, the conversion of all Samsung machines to the new driver was
planned for 3.10, but that work ended up being too late and too invasive
just before the merge window.

Unfortunately, other changes in the Exynos platform resulted in some
Exynos4 setups, particularly the Universal C210 board to be broken. In
order to fix that with minimum risk, so we now leave the existing pwm
clocksource driver in place for all older platforms and use the new
driver only for device tree enabled boards. This way, we can get the
broken machines running again using DT descriptions.

All clocksource changes were implemented by Tomasz, while the DT
registration was rewritten by Arnd.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Tomasz Figa <t.figa@samsung.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
2013-04-21 00:21:05 +02:00