From aca82d1cbb49af34b69ecd4571a0fe48ad9247c1 Mon Sep 17 00:00:00 2001 From: Grygorii Strashko Date: Fri, 25 Sep 2015 12:28:02 -0700 Subject: [PATCH] gpio: omap: move pm runtime in irq_chip.irq_bus_lock/sync_unlock The PM runtime API can't be used in atomic contex on -RT even if it's configured as irqsafe. As result, below error report can be seen when PM runtime API called from IRQ chip's callbacks irq_startup/irq_shutdown/irq_set_type, because they are protected by RAW spinlock: BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917 in_atomic(): 1, irqs_disabled(): 128, pid: 96, name: insmod 3 locks held by insmod/96: #0: (&dev->mutex){......}, at: [] __driver_attach+0x54/0xa0 #1: (&dev->mutex){......}, at: [] __driver_attach+0x60/0xa0 #2: (class){......}, at: [] __irq_get_desc_lock+0x60/0xa4 irq event stamp: 1834 hardirqs last enabled at (1833): [] _raw_spin_unlock_irqrestore+0x88/0x90 hardirqs last disabled at (1834): [] _raw_spin_lock_irqsave+0x2c/0x64 softirqs last enabled at (0): [] copy_process.part.52+0x410/0x19d8 softirqs last disabled at (0): [< (null)>] (null) Preemption disabled at:[< (null)>] (null) CPU: 1 PID: 96 Comm: insmod Tainted: G W O 4.1.3-rt3-00618-g57e2387-dirty #184 Hardware name: Generic DRA74X (Flattened Device Tree) [] (unwind_backtrace) from [] (show_stack+0x20/0x24) [] (show_stack) from [] (dump_stack+0x88/0xdc) [] (dump_stack) from [] (___might_sleep+0x198/0x2a8) [] (___might_sleep) from [] (rt_spin_lock+0x30/0x70) [] (rt_spin_lock) from [] (__pm_runtime_resume+0x68/0xa4) [] (__pm_runtime_resume) from [] (omap_gpio_irq_type+0x188/0x1d8) [] (omap_gpio_irq_type) from [] (__irq_set_trigger+0x68/0x130) [] (__irq_set_trigger) from [] (irq_set_irq_type+0x44/0x6c) [] (irq_set_irq_type) from [] (irq_create_of_mapping+0x120/0x174) [] (irq_create_of_mapping) from [] (of_irq_get+0x48/0x58) [] (of_irq_get) from [] (i2c_device_probe+0x54/0x15c) [] (i2c_device_probe) from [] (driver_probe_device+0x184/0x2c8) [] (driver_probe_device) from [] (__driver_attach+0x9c/0xa0) [] (__driver_attach) from [] (bus_for_each_dev+0x7c/0xb0) [] (bus_for_each_dev) from [] (driver_attach+0x28/0x30) [] (driver_attach) from [] (bus_add_driver+0x154/0x200) [] (bus_add_driver) from [] (driver_register+0x88/0x108) [] (driver_register) from [] (i2c_register_driver+0x3c/0x90) [] (i2c_register_driver) from [] (pcf857x_init+0x18/0x24 [gpio_pcf857x]) [] (pcf857x_init [gpio_pcf857x]) from [] (do_one_initcall+0x128/0x1e8) [] (do_one_initcall) from [] (do_init_module+0x6c/0x1bc) [] (do_init_module) from [] (load_module+0x18e8/0x21c4) [] (load_module) from [] (SyS_init_module+0xfc/0x158) [] (SyS_init_module) from [] (ret_fast_syscall+0x0/0x54) The IRQ chip interface defines only two callbacks which are executed in non-atomic contex - irq_bus_lock/irq_bus_sync_unlock, so lets move PM runtime calls there. Tested-by: Tony Lindgren Tested-by: Austin Schuh Signed-off-by: Grygorii Strashko Acked-by: Santosh Shilimkar Signed-off-by: Linus Walleij --- drivers/gpio/gpio-omap.c | 25 +++++++++++++++---------- 1 file changed, 15 insertions(+), 10 deletions(-) diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 5236db1..a254691 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -496,9 +496,6 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type) (type & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))) return -EINVAL; - if (!BANK_USED(bank)) - pm_runtime_get_sync(bank->dev); - raw_spin_lock_irqsave(&bank->lock, flags); retval = omap_set_gpio_triggering(bank, offset, type); if (retval) { @@ -521,8 +518,6 @@ static int omap_gpio_irq_type(struct irq_data *d, unsigned type) return 0; error: - if (!BANK_USED(bank)) - pm_runtime_put(bank->dev); return retval; } @@ -797,9 +792,6 @@ static unsigned int omap_gpio_irq_startup(struct irq_data *d) unsigned long flags; unsigned offset = d->hwirq; - if (!BANK_USED(bank)) - pm_runtime_get_sync(bank->dev); - raw_spin_lock_irqsave(&bank->lock, flags); if (!LINE_USED(bank->mod_usage, offset)) @@ -815,8 +807,6 @@ static unsigned int omap_gpio_irq_startup(struct irq_data *d) return 0; err: raw_spin_unlock_irqrestore(&bank->lock, flags); - if (!BANK_USED(bank)) - pm_runtime_put(bank->dev); return -EINVAL; } @@ -835,6 +825,19 @@ static void omap_gpio_irq_shutdown(struct irq_data *d) omap_clear_gpio_debounce(bank, offset); omap_disable_gpio_module(bank, offset); raw_spin_unlock_irqrestore(&bank->lock, flags); +} + +static void omap_gpio_irq_bus_lock(struct irq_data *data) +{ + struct gpio_bank *bank = omap_irq_data_get_bank(data); + + if (!BANK_USED(bank)) + pm_runtime_get_sync(bank->dev); +} + +static void gpio_irq_bus_sync_unlock(struct irq_data *data) +{ + struct gpio_bank *bank = omap_irq_data_get_bank(data); /* * If this is the last IRQ to be freed in the bank, @@ -1183,6 +1186,8 @@ static int omap_gpio_probe(struct platform_device *pdev) irqc->irq_unmask = omap_gpio_unmask_irq, irqc->irq_set_type = omap_gpio_irq_type, irqc->irq_set_wake = omap_gpio_wake_enable, + irqc->irq_bus_lock = omap_gpio_irq_bus_lock, + irqc->irq_bus_sync_unlock = gpio_irq_bus_sync_unlock, irqc->name = dev_name(&pdev->dev); bank->irq = platform_get_irq(pdev, 0); -- 2.7.4