All PWM devices have been marked as "might sleep" since v4.5, there is
no longer a need to differentiate on a per-chip basis.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Some PWM drivers are testing the PWMF_ENABLED flag. Create a helper
function to hide the logic behind enabled test. This will allow us to
smoothly move from the current approach to an atomic PWM update
approach.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The driver computes which clock divider it sould be using from the
requested period. This computation assumes that the link between the
register value and the actual divider value is raising 2 to the power of
the registry value.
div = 1 << regvalue
This is true only for the first 5 values out of 8. Next values are 64,
256 and, 1024 - instead of 32, 64, 128.
This affects only the users requesting a period > 0.04369s.
Replace the computation with a look-up table.
Signed-off-by: Gaetan Hug <ghug@induct.be>
Acked-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
The .config() calls clk_get_rate() which might sleep, so we need to set
pwm_chip can_sleep flag. Otherwise, we see the following warning when
using PWM driven heartbeat led.
WARNING: CPU: 0 PID: 0 at kernel/locking/mutex.c:856 mutex_trylock+0x184/0x1a4()
DEBUG_LOCKS_WARN_ON(in_interrupt())
Modules linked in:
CPU: 0 PID: 0 Comm: swapper Not tainted 3.14.0-rc5 #18
[<c0015420>] (unwind_backtrace) from [<c0012cb0>] (show_stack+0x10/0x14)
[<c0012cb0>] (show_stack) from [<c001daf8>] (warn_slowpath_common+0x6c/0x8c)
[<c001daf8>] (warn_slowpath_common) from [<c001dbac>] (warn_slowpath_fmt+0x30/0x40)
[<c001dbac>] (warn_slowpath_fmt) from [<c045df74>] (mutex_trylock+0x184/0x1a4)
[<c045df74>] (mutex_trylock) from [<c0360950>] (clk_prepare_lock+0xc/0xec)
[<c0360950>] (clk_prepare_lock) from [<c0362020>] (clk_get_rate+0xc/0x68)
[<c0362020>] (clk_get_rate) from [<c028d07c>] (mxs_pwm_config+0x20/0x198)
[<c028d07c>] (mxs_pwm_config) from [<c028bde8>] (pwm_config+0x60/0x70)
[<c028bde8>] (pwm_config) from [<c034b61c>] (__led_pwm_set+0x1c/0x3c)
[<c034b61c>] (__led_pwm_set) from [<c034bc3c>] (led_heartbeat_function+0x70/0x110)
[<c034bc3c>] (led_heartbeat_function) from [<c00292f0>] (call_timer_fn+0x7c/0x164)
[<c00292f0>] (call_timer_fn) from [<c00295c8>] (run_timer_softirq+0x1f0/0x260)
[<c00295c8>] (run_timer_softirq) from [<c002255c>] (__do_softirq+0xc4/0x2f0)
[<c002255c>] (__do_softirq) from [<c0022890>] (irq_exit+0xa4/0x10c)
[<c0022890>] (irq_exit) from [<c0010240>] (handle_IRQ+0x34/0x84)
[<c0010240>] (handle_IRQ) from [<c0013524>] (__irq_svc+0x44/0x54)
[<c0013524>] (__irq_svc) from [<c00107f8>] (arch_cpu_idle+0x40/0x48)
[<c00107f8>] (arch_cpu_idle) from [<c005deb8>] (cpu_startup_entry+0x70/0x198)
[<c005deb8>] (cpu_startup_entry) from [<c060aac8>] (start_kernel+0x2a8/0x2f8)
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
stmp_reset_block() may fail, so let's check its return value and
propagate it in the case of error.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Some drivers don't set the .owner fields of the struct device_driver or
struct pwm_ops, which causes the module usage count to become wrong.
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Use global reset function stmp_reset_block instead of mxs_reset_block
to remove <mach/common.h> inclusion.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Encode soc name in the compatible string to know the specific version
hardware block. This is the general approach adopted for most bindings.
Change mxs-pwm binding to use the approach.
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
