From bd9c1b60050e2b7ef6507d8eaa5279afc043e06e Mon Sep 17 00:00:00 2001 From: Shawn Guo Date: Tue, 8 Apr 2014 19:29:57 +0800 Subject: [PATCH] pwm: mxs: set pwm_chip can_sleep flag 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 [] (unwind_backtrace) from [] (show_stack+0x10/0x14) [] (show_stack) from [] (warn_slowpath_common+0x6c/0x8c) [] (warn_slowpath_common) from [] (warn_slowpath_fmt+0x30/0x40) [] (warn_slowpath_fmt) from [] (mutex_trylock+0x184/0x1a4) [] (mutex_trylock) from [] (clk_prepare_lock+0xc/0xec) [] (clk_prepare_lock) from [] (clk_get_rate+0xc/0x68) [] (clk_get_rate) from [] (mxs_pwm_config+0x20/0x198) [] (mxs_pwm_config) from [] (pwm_config+0x60/0x70) [] (pwm_config) from [] (__led_pwm_set+0x1c/0x3c) [] (__led_pwm_set) from [] (led_heartbeat_function+0x70/0x110) [] (led_heartbeat_function) from [] (call_timer_fn+0x7c/0x164) [] (call_timer_fn) from [] (run_timer_softirq+0x1f0/0x260) [] (run_timer_softirq) from [] (__do_softirq+0xc4/0x2f0) [] (__do_softirq) from [] (irq_exit+0xa4/0x10c) [] (irq_exit) from [] (handle_IRQ+0x34/0x84) [] (handle_IRQ) from [] (__irq_svc+0x44/0x54) [] (__irq_svc) from [] (arch_cpu_idle+0x40/0x48) [] (arch_cpu_idle) from [] (cpu_startup_entry+0x70/0x198) [] (cpu_startup_entry) from [] (start_kernel+0x2a8/0x2f8) Reported-by: Stefan Wahren Signed-off-by: Shawn Guo Acked-by: Alexandre Belloni Tested-by: Stefan Wahren Signed-off-by: Thierry Reding --- drivers/pwm/pwm-mxs.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pwm/pwm-mxs.c b/drivers/pwm/pwm-mxs.c index 9475bc7a6f97..4f1bb4e0a426 100644 --- a/drivers/pwm/pwm-mxs.c +++ b/drivers/pwm/pwm-mxs.c @@ -147,6 +147,7 @@ static int mxs_pwm_probe(struct platform_device *pdev) mxs->chip.dev = &pdev->dev; mxs->chip.ops = &mxs_pwm_ops; mxs->chip.base = -1; + mxs->chip.can_sleep = true; ret = of_property_read_u32(np, "fsl,pwm-number", &mxs->chip.npwm); if (ret < 0) { dev_err(&pdev->dev, "failed to get pwm number: %d\n", ret);