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

4 files changed, 72 insertions, 40 deletions

diff --git a/drivers/gpio/gpio-adp5588.c b/drivers/gpio/gpio-adp5588.c
index 3530ccd17e04..da9781a2ef4a 100644
--- 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
index 28da700f5f52..044888fd96a1 100644
--- 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
index c48ed9d89ff5..8b9d7e42c600 100644
--- 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
index a4f1157d6aa0..d4e7a09598fa 100644
--- 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;
 }