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commit b36fdc6853a38a6f8749897a33435635019e0647
parent f4697d9a8a9c7a3ce4d33bb37bb1390f0d17c870
Author: Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed,  5 Sep 2018 09:27:45 -0700

Merge tag 'gpio-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO fixes from Linus Walleij:
 "Some GPIO fixes. The ACPI stuff is probably the most annoying for
  users that get fixed this time.

   - Atomic contexts, cansleep* calls and such fastpath/slopwpath
     things.

   - Defer ACPI event handler registration to late_initcall() so IRQs do
     not fire in our face before other drivers have a chance to register
     handlers.

   - Race condition if a consumer requests a GPIO after
     gpiochip_add_data_with_key() but before of_gpiochip_add()

   - Probe errorpath in the dwapb driver"

* tag 'gpio-v4.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpio: Fix crash due to registration race
  gpio: dwapb: Fix error handling in dwapb_gpio_probe()
  gpiolib-acpi: Register GpioInt ACPI event handlers from a late_initcall
  gpiolib: acpi: Switch to cansleep version of GPIO library call
  gpio: adp5588: Fix sleep-in-atomic-context bug

Diffstat:
Mdrivers/gpio/gpio-adp5588.c | 24++++++++++++++++++++----
Mdrivers/gpio/gpio-dwapb.c | 1+
Mdrivers/gpio/gpiolib-acpi.c | 86++++++++++++++++++++++++++++++++++++++++++++++---------------------------------
Mdrivers/gpio/gpiolib-of.c | 1+
4 files changed, 72 insertions(+), 40 deletions(-)

diff --git a/drivers/gpio/gpio-adp5588.c b/drivers/gpio/gpio-adp5588.c @@ -41,6 +41,8 @@ struct adp5588_gpio { uint8_t int_en[3]; uint8_t irq_mask[3]; uint8_t irq_stat[3]; + uint8_t int_input_en[3]; + uint8_t int_lvl_cached[3]; }; static int adp5588_gpio_read(struct i2c_client *client, u8 reg) @@ -173,12 +175,28 @@ static void adp5588_irq_bus_sync_unlock(struct irq_data *d) struct adp5588_gpio *dev = irq_data_get_irq_chip_data(d); int i; - for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) + for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) { + if (dev->int_input_en[i]) { + mutex_lock(&dev->lock); + dev->dir[i] &= ~dev->int_input_en[i]; + dev->int_input_en[i] = 0; + adp5588_gpio_write(dev->client, GPIO_DIR1 + i, + dev->dir[i]); + mutex_unlock(&dev->lock); + } + + if (dev->int_lvl_cached[i] != dev->int_lvl[i]) { + dev->int_lvl_cached[i] = dev->int_lvl[i]; + adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + i, + dev->int_lvl[i]); + } + if (dev->int_en[i] ^ dev->irq_mask[i]) { dev->int_en[i] = dev->irq_mask[i]; adp5588_gpio_write(dev->client, GPIO_INT_EN1 + i, dev->int_en[i]); } + } mutex_unlock(&dev->irq_lock); } @@ -221,9 +239,7 @@ static int adp5588_irq_set_type(struct irq_data *d, unsigned int type) else return -EINVAL; - adp5588_gpio_direction_input(&dev->gpio_chip, gpio); - adp5588_gpio_write(dev->client, GPIO_INT_LVL1 + bank, - dev->int_lvl[bank]); + dev->int_input_en[bank] |= bit; return 0; } diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c @@ -728,6 +728,7 @@ static int dwapb_gpio_probe(struct platform_device *pdev) out_unregister: dwapb_gpio_unregister(gpio); dwapb_irq_teardown(gpio); + clk_disable_unprepare(gpio->clk); return err; } diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c @@ -25,7 +25,6 @@ struct acpi_gpio_event { struct list_head node; - struct list_head initial_sync_list; acpi_handle handle; unsigned int pin; unsigned int irq; @@ -49,10 +48,19 @@ struct acpi_gpio_chip { struct mutex conn_lock; struct gpio_chip *chip; struct list_head events; + struct list_head deferred_req_irqs_list_entry; }; -static LIST_HEAD(acpi_gpio_initial_sync_list); -static DEFINE_MUTEX(acpi_gpio_initial_sync_list_lock); +/* + * For gpiochips which call acpi_gpiochip_request_interrupts() before late_init + * (so builtin drivers) we register the ACPI GpioInt event handlers from a + * late_initcall_sync handler, so that other builtin drivers can register their + * OpRegions before the event handlers can run. This list contains gpiochips + * for which the acpi_gpiochip_request_interrupts() has been deferred. + */ +static DEFINE_MUTEX(acpi_gpio_deferred_req_irqs_lock); +static LIST_HEAD(acpi_gpio_deferred_req_irqs_list); +static bool acpi_gpio_deferred_req_irqs_done; static int acpi_gpiochip_find(struct gpio_chip *gc, void *data) { @@ -89,21 +97,6 @@ static struct gpio_desc *acpi_get_gpiod(char *path, int pin) return gpiochip_get_desc(chip, pin); } -static void acpi_gpio_add_to_initial_sync_list(struct acpi_gpio_event *event) -{ - mutex_lock(&acpi_gpio_initial_sync_list_lock); - list_add(&event->initial_sync_list, &acpi_gpio_initial_sync_list); - mutex_unlock(&acpi_gpio_initial_sync_list_lock); -} - -static void acpi_gpio_del_from_initial_sync_list(struct acpi_gpio_event *event) -{ - mutex_lock(&acpi_gpio_initial_sync_list_lock); - if (!list_empty(&event->initial_sync_list)) - list_del_init(&event->initial_sync_list); - mutex_unlock(&acpi_gpio_initial_sync_list_lock); -} - static irqreturn_t acpi_gpio_irq_handler(int irq, void *data) { struct acpi_gpio_event *event = data; @@ -186,7 +179,7 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares, gpiod_direction_input(desc); - value = gpiod_get_value(desc); + value = gpiod_get_value_cansleep(desc); ret = gpiochip_lock_as_irq(chip, pin); if (ret) { @@ -229,7 +222,6 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares, event->irq = irq; event->pin = pin; event->desc = desc; - INIT_LIST_HEAD(&event->initial_sync_list); ret = request_threaded_irq(event->irq, NULL, handler, irqflags, "ACPI:Event", event); @@ -251,10 +243,9 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares, * may refer to OperationRegions from other (builtin) drivers which * may be probed after us. */ - if (handler == acpi_gpio_irq_handler && - (((irqflags & IRQF_TRIGGER_RISING) && value == 1) || - ((irqflags & IRQF_TRIGGER_FALLING) && value == 0))) - acpi_gpio_add_to_initial_sync_list(event); + if (((irqflags & IRQF_TRIGGER_RISING) && value == 1) || + ((irqflags & IRQF_TRIGGER_FALLING) && value == 0)) + handler(event->irq, event); return AE_OK; @@ -283,6 +274,7 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) struct acpi_gpio_chip *acpi_gpio; acpi_handle handle; acpi_status status; + bool defer; if (!chip->parent || !chip->to_irq) return; @@ -295,6 +287,16 @@ void acpi_gpiochip_request_interrupts(struct gpio_chip *chip) if (ACPI_FAILURE(status)) return; + mutex_lock(&acpi_gpio_deferred_req_irqs_lock); + defer = !acpi_gpio_deferred_req_irqs_done; + if (defer) + list_add(&acpi_gpio->deferred_req_irqs_list_entry, + &acpi_gpio_deferred_req_irqs_list); + mutex_unlock(&acpi_gpio_deferred_req_irqs_lock); + + if (defer) + return; + acpi_walk_resources(handle, "_AEI", acpi_gpiochip_request_interrupt, acpi_gpio); } @@ -325,11 +327,14 @@ void acpi_gpiochip_free_interrupts(struct gpio_chip *chip) if (ACPI_FAILURE(status)) return; + mutex_lock(&acpi_gpio_deferred_req_irqs_lock); + if (!list_empty(&acpi_gpio->deferred_req_irqs_list_entry)) + list_del_init(&acpi_gpio->deferred_req_irqs_list_entry); + mutex_unlock(&acpi_gpio_deferred_req_irqs_lock); + list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) { struct gpio_desc *desc; - acpi_gpio_del_from_initial_sync_list(event); - if (irqd_is_wakeup_set(irq_get_irq_data(event->irq))) disable_irq_wake(event->irq); @@ -1052,6 +1057,7 @@ void acpi_gpiochip_add(struct gpio_chip *chip) acpi_gpio->chip = chip; INIT_LIST_HEAD(&acpi_gpio->events); + INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry); status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio); if (ACPI_FAILURE(status)) { @@ -1198,20 +1204,28 @@ bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id) return con_id == NULL; } -/* Sync the initial state of handlers after all builtin drivers have probed */ -static int acpi_gpio_initial_sync(void) +/* Run deferred acpi_gpiochip_request_interrupts() */ +static int acpi_gpio_handle_deferred_request_interrupts(void) { - struct acpi_gpio_event *event, *ep; + struct acpi_gpio_chip *acpi_gpio, *tmp; + + mutex_lock(&acpi_gpio_deferred_req_irqs_lock); + list_for_each_entry_safe(acpi_gpio, tmp, + &acpi_gpio_deferred_req_irqs_list, + deferred_req_irqs_list_entry) { + acpi_handle handle; - mutex_lock(&acpi_gpio_initial_sync_list_lock); - list_for_each_entry_safe(event, ep, &acpi_gpio_initial_sync_list, - initial_sync_list) { - acpi_evaluate_object(event->handle, NULL, NULL, NULL); - list_del_init(&event->initial_sync_list); + handle = ACPI_HANDLE(acpi_gpio->chip->parent); + acpi_walk_resources(handle, "_AEI", + acpi_gpiochip_request_interrupt, acpi_gpio); + + list_del_init(&acpi_gpio->deferred_req_irqs_list_entry); } - mutex_unlock(&acpi_gpio_initial_sync_list_lock); + + acpi_gpio_deferred_req_irqs_done = true; + mutex_unlock(&acpi_gpio_deferred_req_irqs_lock); return 0; } /* We must use _sync so that this runs after the first deferred_probe run */ -late_initcall_sync(acpi_gpio_initial_sync); +late_initcall_sync(acpi_gpio_handle_deferred_request_interrupts); diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c @@ -31,6 +31,7 @@ static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data) struct of_phandle_args *gpiospec = data; return chip->gpiodev->dev.of_node == gpiospec->np && + chip->of_xlate && chip->of_xlate(chip, gpiospec, NULL) >= 0; }