Merge tag 'gpio-updates-for-v5.9-part2' of...

Merge tag 'gpio-updates-for-v5.9-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel

gpio updates for v5.9 - part 2

- several improvements and minor tweaks to the GPIO character device code

drivers/gpio/gpio-arizona.c

@@ -64,6 +64,7 @@ static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
 		ret = pm_runtime_get_sync(chip->parent);
 		if (ret < 0) {
 			dev_err(chip->parent, "Failed to resume: %d\n", ret);
+			pm_runtime_put_autosuspend(chip->parent);
 			return ret;
 		}
 
@@ -72,12 +73,15 @@ static int arizona_gpio_get(struct gpio_chip *chip, unsigned offset)
 		if (ret < 0) {
 			dev_err(chip->parent, "Failed to drop cache: %d\n",
 				ret);
+			pm_runtime_put_autosuspend(chip->parent);
 			return ret;
 		}
 
 		ret = regmap_read(arizona->regmap, reg, &val);
-		if (ret < 0)
+		if (ret < 0) {
+			pm_runtime_put_autosuspend(chip->parent);
 			return ret;
+		}
 
 		pm_runtime_mark_last_busy(chip->parent);
 		pm_runtime_put_autosuspend(chip->parent);
@@ -106,6 +110,7 @@ static int arizona_gpio_direction_out(struct gpio_chip *chip,
 		ret = pm_runtime_get_sync(chip->parent);
 		if (ret < 0) {
 			dev_err(chip->parent, "Failed to resume: %d\n", ret);
+			pm_runtime_put(chip->parent);
 			return ret;
 		}
 	}

drivers/gpio/gpio-pca953x.c

@@ -108,6 +108,84 @@ static const struct i2c_device_id pca953x_id[] = {
 };
 MODULE_DEVICE_TABLE(i2c, pca953x_id);
 
+#ifdef CONFIG_GPIO_PCA953X_IRQ
+
+#include <linux/dmi.h>
+#include <linux/gpio.h>
+#include <linux/list.h>
+
+static const struct dmi_system_id pca953x_dmi_acpi_irq_info[] = {
+	{
+		/*
+		 * On Intel Galileo Gen 2 board the IRQ pin of one of
+		 * the I²C GPIO expanders, which has GpioInt() resource,
+		 * is provided as an absolute number instead of being
+		 * relative. Since first controller (gpio-sch.c) and
+		 * second (gpio-dwapb.c) are at the fixed bases, we may
+		 * safely refer to the number in the global space to get
+		 * an IRQ out of it.
+		 */
+		.matches = {
+			DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
+		},
+	},
+	{}
+};
+
+#ifdef CONFIG_ACPI
+static int pca953x_acpi_get_pin(struct acpi_resource *ares, void *data)
+{
+	struct acpi_resource_gpio *agpio;
+	int *pin = data;
+
+	if (acpi_gpio_get_irq_resource(ares, &agpio))
+		*pin = agpio->pin_table[0];
+	return 1;
+}
+
+static int pca953x_acpi_find_pin(struct device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(dev);
+	int pin = -ENOENT, ret;
+	LIST_HEAD(r);
+
+	ret = acpi_dev_get_resources(adev, &r, pca953x_acpi_get_pin, &pin);
+	acpi_dev_free_resource_list(&r);
+	if (ret < 0)
+		return ret;
+
+	return pin;
+}
+#else
+static inline int pca953x_acpi_find_pin(struct device *dev) { return -ENXIO; }
+#endif
+
+static int pca953x_acpi_get_irq(struct device *dev)
+{
+	int pin, ret;
+
+	pin = pca953x_acpi_find_pin(dev);
+	if (pin < 0)
+		return pin;
+
+	dev_info(dev, "Applying ACPI interrupt quirk (GPIO %d)\n", pin);
+
+	if (!gpio_is_valid(pin))
+		return -EINVAL;
+
+	ret = gpio_request(pin, "pca953x interrupt");
+	if (ret)
+		return ret;
+
+	ret = gpio_to_irq(pin);
+
+	/* When pin is used as an IRQ, no need to keep it requested */
+	gpio_free(pin);
+
+	return ret;
+}
+#endif
+
 static const struct acpi_device_id pca953x_acpi_ids[] = {
 	{ "INT3491", 16 | PCA953X_TYPE | PCA_LATCH_INT, },
 	{ }
@@ -323,6 +401,7 @@ static const struct regmap_config pca953x_ai_i2c_regmap = {
 	.writeable_reg = pca953x_writeable_register,
 	.volatile_reg = pca953x_volatile_register,
 
+	.disable_locking = true,
 	.cache_type = REGCACHE_RBTREE,
 	.max_register = 0x7f,
 };
@@ -624,8 +703,6 @@ static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
 	DECLARE_BITMAP(reg_direction, MAX_LINE);
 	int level;
 
-	pca953x_read_regs(chip, chip->regs->direction, reg_direction);
-
 	if (chip->driver_data & PCA_PCAL) {
 		/* Enable latch on interrupt-enabled inputs */
 		pca953x_write_regs(chip, PCAL953X_IN_LATCH, chip->irq_mask);
@@ -636,7 +713,11 @@ static void pca953x_irq_bus_sync_unlock(struct irq_data *d)
 		pca953x_write_regs(chip, PCAL953X_INT_MASK, irq_mask);
 	}
 
+	/* Switch direction to input if needed */
+	pca953x_read_regs(chip, chip->regs->direction, reg_direction);
+
 	bitmap_or(irq_mask, chip->irq_trig_fall, chip->irq_trig_raise, gc->ngpio);
+	bitmap_complement(reg_direction, reg_direction, gc->ngpio);
 	bitmap_and(irq_mask, irq_mask, reg_direction, gc->ngpio);
 
 	/* Look for any newly setup interrupt */
@@ -735,14 +816,16 @@ static irqreturn_t pca953x_irq_handler(int irq, void *devid)
 	struct gpio_chip *gc = &chip->gpio_chip;
 	DECLARE_BITMAP(pending, MAX_LINE);
 	int level;
+	bool ret;
 
-	if (!pca953x_irq_pending(chip, pending))
-		return IRQ_NONE;
+	mutex_lock(&chip->i2c_lock);
+	ret = pca953x_irq_pending(chip, pending);
+	mutex_unlock(&chip->i2c_lock);
 
 	for_each_set_bit(level, pending, gc->ngpio)
 		handle_nested_irq(irq_find_mapping(gc->irq.domain, level));
 
-	return IRQ_HANDLED;
+	return IRQ_RETVAL(ret);
 }
 
 static int pca953x_irq_setup(struct pca953x_chip *chip, int irq_base)
@@ -753,6 +836,12 @@ static int pca953x_irq_setup(struct pca953x_chip *chip, int irq_base)
 	DECLARE_BITMAP(irq_stat, MAX_LINE);
 	int ret;
 
+	if (dmi_first_match(pca953x_dmi_acpi_irq_info)) {
+		ret = pca953x_acpi_get_irq(&client->dev);
+		if (ret > 0)
+			client->irq = ret;
+	}
+
 	if (!client->irq)
 		return 0;
 

drivers/gpio/gpiolib-sysfs.c

@@ -11,6 +11,7 @@
 #include <linux/ctype.h>
 
 #include "gpiolib.h"
+#include "gpiolib-sysfs.h"
 
 #define GPIO_IRQF_TRIGGER_FALLING	BIT(0)
 #define GPIO_IRQF_TRIGGER_RISING	BIT(1)

drivers/gpio/gpiolib-sysfs.h

+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef GPIOLIB_SYSFS_H
+#define GPIOLIB_SYSFS_H
+
+#ifdef CONFIG_GPIO_SYSFS
+
+int gpiochip_sysfs_register(struct gpio_device *gdev);
+void gpiochip_sysfs_unregister(struct gpio_device *gdev);
+
+#else
+
+static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
+{
+	return 0;
+}
+
+static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
+{
+}
+
+#endif /* CONFIG_GPIO_SYSFS */
+
+#endif /* GPIOLIB_SYSFS_H */

drivers/gpio/gpiolib.c

@@ -26,6 +26,7 @@
 #include "gpiolib-of.h"
 #include "gpiolib-acpi.h"
 #include "gpiolib-cdev.h"
+#include "gpiolib-sysfs.h"
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/gpio.h>
@@ -614,7 +615,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 
 	spin_unlock_irqrestore(&gpio_lock, flags);
 
-	ATOMIC_INIT_NOTIFIER_HEAD(&gdev->notifier);
+	BLOCKING_INIT_NOTIFIER_HEAD(&gdev->notifier);
 
 #ifdef CONFIG_PINCTRL
 	INIT_LIST_HEAD(&gdev->pin_ranges);
@@ -2048,8 +2049,8 @@ static bool gpiod_free_commit(struct gpio_desc *desc)
 	}
 
 	spin_unlock_irqrestore(&gpio_lock, flags);
-	atomic_notifier_call_chain(&desc->gdev->notifier,
-				   GPIOLINE_CHANGED_RELEASED, desc);
+	blocking_notifier_call_chain(&desc->gdev->notifier,
+				     GPIOLINE_CHANGED_RELEASED, desc);
 
 	return ret;
 }
@@ -3926,8 +3927,8 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
 		return ERR_PTR(ret);
 	}
 
-	atomic_notifier_call_chain(&desc->gdev->notifier,
-				   GPIOLINE_CHANGED_REQUESTED, desc);
+	blocking_notifier_call_chain(&desc->gdev->notifier,
+				     GPIOLINE_CHANGED_REQUESTED, desc);
 
 	return desc;
 }
@@ -3994,8 +3995,8 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
 		return ERR_PTR(ret);
 	}
 
-	atomic_notifier_call_chain(&desc->gdev->notifier,
-				   GPIOLINE_CHANGED_REQUESTED, desc);
+	blocking_notifier_call_chain(&desc->gdev->notifier,
+				     GPIOLINE_CHANGED_REQUESTED, desc);
 
 	return desc;
 }

drivers/gpio/gpiolib.h

@@ -56,7 +56,7 @@ struct gpio_device {
 	const char		*label;
 	void			*data;
 	struct list_head        list;
-	struct atomic_notifier_head notifier;
+	struct blocking_notifier_head notifier;
 
 #ifdef CONFIG_PINCTRL
 	/*
@@ -175,22 +175,4 @@ static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
 #define chip_dbg(gc, fmt, ...)					\
 	dev_dbg(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__)
 
-#ifdef CONFIG_GPIO_SYSFS
-
-int gpiochip_sysfs_register(struct gpio_device *gdev);
-void gpiochip_sysfs_unregister(struct gpio_device *gdev);
-
-#else
-
-static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
-{
-	return 0;
-}
-
-static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
-{
-}
-
-#endif /* CONFIG_GPIO_SYSFS */
-
 #endif /* GPIOLIB_H */

include/uapi/linux/gpio.h

@@ -71,8 +71,8 @@ enum {
  * of a GPIO line
  * @info: updated line information
  * @timestamp: estimate of time of status change occurrence, in nanoseconds
- * and GPIOLINE_CHANGED_CONFIG
  * @event_type: one of GPIOLINE_CHANGED_REQUESTED, GPIOLINE_CHANGED_RELEASED
+ * and GPIOLINE_CHANGED_CONFIG
  *
  * Note: struct gpioline_info embedded here has 32-bit alignment on its own,
  * but it works fine with 64-bit alignment too. With its 72 byte size, we can

tools/gpio/gpio-event-mon.c

@@ -45,7 +45,7 @@ int monitor_device(const char *device_name,
 	if (fd == -1) {
 		ret = -errno;
 		fprintf(stderr, "Failed to open %s\n", chrdev_name);
-		goto exit_close_error;
+		goto exit_free_name;
 	}
 
 	req.lineoffset = line;
@@ -117,6 +117,7 @@ int monitor_device(const char *device_name,
 exit_close_error:
 	if (close(fd) == -1)
 		perror("Failed to close GPIO character device file");
+exit_free_name:
 	free(chrdev_name);
 	return ret;
 }

tools/gpio/gpio-utils.c

@@ -75,7 +75,7 @@ int gpiotools_request_linehandle(const char *device_name, unsigned int *lines,
 		ret = -errno;
 		fprintf(stderr, "Failed to open %s, %s\n",
 			chrdev_name, strerror(errno));
-		goto exit_close_error;
+		goto exit_free_name;
 	}
 
 	for (i = 0; i < nlines; i++)
@@ -94,9 +94,9 @@ int gpiotools_request_linehandle(const char *device_name, unsigned int *lines,
 			"GPIO_GET_LINEHANDLE_IOCTL", ret, strerror(errno));
 	}
 
-exit_close_error:
 	if (close(fd) == -1)
 		perror("Failed to close GPIO character device file");
+exit_free_name:
 	free(chrdev_name);
 	return ret < 0 ? ret : req.fd;
 }

tools/gpio/lsgpio.c

@@ -94,7 +94,7 @@ int list_device(const char *device_name)
 	if (fd == -1) {
 		ret = -errno;
 		fprintf(stderr, "Failed to open %s\n", chrdev_name);
-		goto exit_close_error;
+		goto exit_free_name;
 	}
 
 	/* Inspect this GPIO chip */
@@ -141,6 +141,7 @@ int list_device(const char *device_name)
 exit_close_error:
 	if (close(fd) == -1)
 		perror("Failed to close GPIO character device file");
+exit_free_name:
 	free(chrdev_name);
 	return ret;
 }