1 files changed, 216 insertions, 195 deletions

diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index a8be286eff86..77f6f2936dc2 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -1,47 +1,58 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Internal GPIO functions.
  *
  * Copyright (C) 2013, Intel Corporation
  * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
  */
 
 #ifndef GPIOLIB_H
 #define GPIOLIB_H
 
-#include <linux/gpio/driver.h>
-#include <linux/err.h>
+#include <linux/cdev.h>
 #include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h> /* for enum gpiod_flags */
+#include <linux/gpio/driver.h>
 #include <linux/module.h>
-#include <linux/cdev.h>
+#include <linux/notifier.h>
+#include <linux/spinlock.h>
+#include <linux/srcu.h>
+#include <linux/workqueue.h>
 
-enum of_gpio_flags;
-enum gpiod_flags;
-enum gpio_lookup_flags;
-struct acpi_device;
+#define GPIOCHIP_NAME	"gpiochip"
 
 /**
  * struct gpio_device - internal state container for GPIO devices
- * @id: numerical ID number for the GPIO chip
  * @dev: the GPIO device struct
  * @chrdev: character device for the GPIO device
- * @mockdev: class device used by the deprecated sysfs interface (may be
- * NULL)
+ * @id: numerical ID number for the GPIO chip
  * @owner: helps prevent removal of modules exporting active GPIOs
  * @chip: pointer to the corresponding gpiochip, holding static
  * data for this device
  * @descs: array of ngpio descriptors.
+ * @valid_mask: If not %NULL, holds bitmask of GPIOs which are valid to be
+ * used from the chip.
+ * @desc_srcu: ensures consistent state of GPIO descriptors exposed to users
  * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
  * of the @descs array.
+ * @can_sleep: indicate whether the GPIO chip driver's callbacks can sleep
+ * implying that they cannot be used from atomic context
  * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
  * at device creation time.
  * @label: a descriptive name for the GPIO device, such as the part number
  * or name of the IP component in a System on Chip.
  * @data: per-instance data assigned by the driver
  * @list: links gpio_device:s together for traversal
+ * @line_state_notifier: used to notify subscribers about lines being
+ *                       requested, released or reconfigured
+ * @line_state_lock: RW-spinlock protecting the line state notifier
+ * @line_state_wq: used to emit line state events from a separate thread in
+ *                 process context
+ * @device_notifier: used to notify character device wait queues about the GPIO
+ *                   device being unregistered
+ * @srcu: protects the pointer to the underlying GPIO chip
+ * @pin_ranges: range of pins served by the GPIO driver
  *
  * This state container holds most of the runtime variable data
  * for a GPIO device and can hold references and live on after the
@@ -49,18 +60,25 @@ struct acpi_device;
  * userspace.
  */
 struct gpio_device {
-	int			id;
 	struct device		dev;
 	struct cdev		chrdev;
-	struct device		*mockdev;
+	int			id;
 	struct module		*owner;
-	struct gpio_chip	*chip;
+	struct gpio_chip __rcu	*chip;
 	struct gpio_desc	*descs;
-	int			base;
+	unsigned long		*valid_mask;
+	struct srcu_struct	desc_srcu;
+	unsigned int		base;
 	u16			ngpio;
-	char			*label;
+	bool			can_sleep;
+	const char		*label;
 	void			*data;
 	struct list_head        list;
+	struct raw_notifier_head line_state_notifier;
+	rwlock_t		line_state_lock;
+	struct workqueue_struct	*line_state_wq;
+	struct blocking_notifier_head device_notifier;
+	struct srcu_struct	srcu;
 
 #ifdef CONFIG_PINCTRL
 	/*
@@ -73,211 +91,214 @@ struct gpio_device {
 #endif
 };
 
-/**
- * struct acpi_gpio_info - ACPI GPIO specific information
- * @flags: GPIO initialization flags
- * @gpioint: if %true this GPIO is of type GpioInt otherwise type is GpioIo
- * @polarity: interrupt polarity as provided by ACPI
- * @triggering: triggering type as provided by ACPI
- */
-struct acpi_gpio_info {
-	enum gpiod_flags flags;
-	bool gpioint;
-	int polarity;
-	int triggering;
-};
-
-/* gpio suffixes used for ACPI and device tree lookup */
-static const char * const gpio_suffixes[] = { "gpios", "gpio" };
-
-#ifdef CONFIG_OF_GPIO
-struct gpio_desc *of_find_gpio(struct device *dev,
-			       const char *con_id,
-			       unsigned int idx,
-			       enum gpio_lookup_flags *flags);
-struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
-		   const char *list_name, int index, enum of_gpio_flags *flags);
-int of_gpiochip_add(struct gpio_chip *gc);
-void of_gpiochip_remove(struct gpio_chip *gc);
-#else
-static inline struct gpio_desc *of_find_gpio(struct device *dev,
-					     const char *con_id,
-					     unsigned int idx,
-					     enum gpio_lookup_flags *flags)
+static inline struct gpio_device *to_gpio_device(struct device *dev)
 {
-	return ERR_PTR(-ENOENT);
+	return container_of(dev, struct gpio_device, dev);
 }
-static inline struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
-		   const char *list_name, int index, enum of_gpio_flags *flags)
-{
-	return ERR_PTR(-ENOENT);
-}
-static inline int of_gpiochip_add(struct gpio_chip *gc) { return 0; }
-static inline void of_gpiochip_remove(struct gpio_chip *gc) { }
-#endif /* CONFIG_OF_GPIO */
-
-#ifdef CONFIG_ACPI
-void acpi_gpiochip_add(struct gpio_chip *chip);
-void acpi_gpiochip_remove(struct gpio_chip *chip);
-
-void acpi_gpiochip_request_interrupts(struct gpio_chip *chip);
-void acpi_gpiochip_free_interrupts(struct gpio_chip *chip);
-
-int acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags,
-				 enum gpiod_flags update);
 
-struct gpio_desc *acpi_find_gpio(struct device *dev,
-				 const char *con_id,
-				 unsigned int idx,
-				 enum gpiod_flags *dflags,
-				 enum gpio_lookup_flags *lookupflags);
-struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
-				      const char *propname, int index,
-				      struct acpi_gpio_info *info);
+/* GPIO suffixes used for ACPI and device tree lookup */
+extern const char *const gpio_suffixes[];
+
+#define for_each_gpio_property_name(propname, con_id)					\
+	for (const char * const *__suffixes = gpio_suffixes;				\
+	     *__suffixes && ({								\
+		const char *__gs = *__suffixes;						\
+											\
+		if (con_id)								\
+			snprintf(propname, sizeof(propname), "%s-%s", con_id, __gs);	\
+		else									\
+			snprintf(propname, sizeof(propname), "%s", __gs);		\
+		1;									\
+	     });									\
+	     __suffixes++)
 
-int acpi_gpio_count(struct device *dev, const char *con_id);
-
-bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id);
-#else
-static inline void acpi_gpiochip_add(struct gpio_chip *chip) { }
-static inline void acpi_gpiochip_remove(struct gpio_chip *chip) { }
-
-static inline void
-acpi_gpiochip_request_interrupts(struct gpio_chip *chip) { }
-
-static inline void
-acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { }
-
-static inline int
-acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
-{
-	return 0;
-}
-
-static inline struct gpio_desc *
-acpi_find_gpio(struct device *dev, const char *con_id,
-	       unsigned int idx, enum gpiod_flags *dflags,
-	       enum gpio_lookup_flags *lookupflags)
-{
-	return ERR_PTR(-ENOENT);
-}
-static inline struct gpio_desc *
-acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname,
-		    int index, struct acpi_gpio_info *info)
-{
-	return ERR_PTR(-ENXIO);
-}
-static inline int acpi_gpio_count(struct device *dev, const char *con_id)
-{
-	return -ENODEV;
-}
-
-static inline bool acpi_can_fallback_to_crs(struct acpi_device *adev,
-					    const char *con_id)
-{
-	return false;
-}
-#endif
-
-struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, u16 hwnum);
-void gpiod_set_array_value_complex(bool raw, bool can_sleep,
-				   unsigned int array_size,
-				   struct gpio_desc **desc_array,
-				   int *value_array);
+/**
+ * struct gpio_array - Opaque descriptor for a structure of GPIO array attributes
+ *
+ * @desc:		Array of pointers to the GPIO descriptors
+ * @size:		Number of elements in desc
+ * @gdev:		Parent GPIO device
+ * @get_mask:		Get mask used in fastpath
+ * @set_mask:		Set mask used in fastpath
+ * @invert_mask:	Invert mask used in fastpath
+ *
+ * This structure is attached to struct gpiod_descs obtained from
+ * gpiod_get_array() and can be passed back to get/set array functions in order
+ * to activate fast processing path if applicable.
+ */
+struct gpio_array {
+	struct gpio_desc	**desc;
+	unsigned int		size;
+	struct gpio_device	*gdev;
+	unsigned long		*get_mask;
+	unsigned long		*set_mask;
+	unsigned long		invert_mask[];
+};
 
-extern struct spinlock gpio_lock;
-extern struct list_head gpio_devices;
+#define for_each_gpio_desc(gc, desc)					\
+	for (unsigned int __i = 0;					\
+	     __i < gc->ngpio && (desc = gpiochip_get_desc(gc, __i));	\
+	     __i++)							\
+
+#define for_each_gpio_desc_with_flag(gc, desc, flag)			\
+	for_each_gpio_desc(gc, desc)					\
+		if (!test_bit(flag, &desc->flags)) {} else
+
+int gpiod_get_array_value_complex(bool raw, bool can_sleep,
+				  unsigned int array_size,
+				  struct gpio_desc **desc_array,
+				  struct gpio_array *array_info,
+				  unsigned long *value_bitmap);
+int gpiod_set_array_value_complex(bool raw, bool can_sleep,
+				  unsigned int array_size,
+				  struct gpio_desc **desc_array,
+				  struct gpio_array *array_info,
+				  unsigned long *value_bitmap);
+
+int gpiod_set_transitory(struct gpio_desc *desc, bool transitory);
+
+void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action);
+int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value);
+int gpiod_direction_input_nonotify(struct gpio_desc *desc);
+
+struct gpio_desc_label {
+	struct rcu_head rh;
+	char str[];
+};
 
+/**
+ * struct gpio_desc - Opaque descriptor for a GPIO
+ *
+ * @gdev:		Pointer to the parent GPIO device
+ * @flags:		Binary descriptor flags
+ * @label:		Name of the consumer
+ * @name:		Line name
+ * @hog:		Pointer to the device node that hogs this line (if any)
+ * @debounce_period_us:	Debounce period in microseconds
+ *
+ * These are obtained using gpiod_get() and are preferable to the old
+ * integer-based handles.
+ *
+ * Contrary to integers, a pointer to a &struct gpio_desc is guaranteed to be
+ * valid until the GPIO is released.
+ */
 struct gpio_desc {
 	struct gpio_device	*gdev;
 	unsigned long		flags;
 /* flag symbols are bit numbers */
-#define FLAG_REQUESTED	0
-#define FLAG_IS_OUT	1
-#define FLAG_EXPORT	2	/* protected by sysfs_lock */
-#define FLAG_SYSFS	3	/* exported via /sys/class/gpio/control */
-#define FLAG_ACTIVE_LOW	6	/* value has active low */
-#define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */
-#define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */
-#define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */
-#define FLAG_IS_HOGGED	11	/* GPIO is hogged */
-#define FLAG_SLEEP_MAY_LOOSE_VALUE 12	/* GPIO may loose value in sleep */
+#define GPIOD_FLAG_REQUESTED		0  /* GPIO is in use */
+#define GPIOD_FLAG_IS_OUT		1  /* GPIO is in output mode */
+#define GPIOD_FLAG_EXPORT		2  /* GPIO is exported to user-space */
+#define GPIOD_FLAG_SYSFS		3  /* GPIO is exported via /sys/class/gpio */
+#define GPIOD_FLAG_ACTIVE_LOW		6  /* GPIO is active-low */
+#define GPIOD_FLAG_OPEN_DRAIN		7  /* GPIO is open drain type */
+#define GPIOD_FLAG_OPEN_SOURCE		8  /* GPIO is open source type */
+#define GPIOD_FLAG_USED_AS_IRQ		9  /* GPIO is connected to an IRQ */
+#define GPIOD_FLAG_IRQ_IS_ENABLED	10 /* GPIO is connected to an enabled IRQ */
+#define GPIOD_FLAG_IS_HOGGED		11 /* GPIO is hogged */
+#define GPIOD_FLAG_TRANSITORY		12 /* GPIO may lose value in sleep or reset */
+#define GPIOD_FLAG_PULL_UP		13 /* GPIO has pull up enabled */
+#define GPIOD_FLAG_PULL_DOWN		14 /* GPIO has pull down enabled */
+#define GPIOD_FLAG_BIAS_DISABLE		15 /* GPIO has pull disabled */
+#define GPIOD_FLAG_EDGE_RISING		16 /* GPIO CDEV detects rising edge events */
+#define GPIOD_FLAG_EDGE_FALLING		17 /* GPIO CDEV detects falling edge events */
+#define GPIOD_FLAG_EVENT_CLOCK_REALTIME	18 /* GPIO CDEV reports REALTIME timestamps in events */
+#define GPIOD_FLAG_EVENT_CLOCK_HTE	19 /* GPIO CDEV reports hardware timestamps in events */
+#define GPIOD_FLAG_SHARED		20 /* GPIO is shared by multiple consumers */
+#define GPIOD_FLAG_SHARED_PROXY		21 /* GPIO is a virtual proxy to a physically shared pin. */
 
 	/* Connection label */
-	const char		*label;
+	struct gpio_desc_label __rcu *label;
 	/* Name of the GPIO */
 	const char		*name;
+#ifdef CONFIG_OF_DYNAMIC
+	struct device_node	*hog;
+#endif
+#ifdef CONFIG_GPIO_CDEV
+	/* debounce period in microseconds */
+	unsigned int		debounce_period_us;
+#endif
+};
+
+#define gpiod_not_found(desc)		(IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
+
+struct gpio_chip_guard {
+	struct gpio_device *gdev;
+	struct gpio_chip *gc;
+	int idx;
 };
 
+DEFINE_CLASS(gpio_chip_guard,
+	     struct gpio_chip_guard,
+	     srcu_read_unlock(&_T.gdev->srcu, _T.idx),
+	     ({
+		struct gpio_chip_guard _guard;
+
+		_guard.gdev = desc->gdev;
+		_guard.idx = srcu_read_lock(&_guard.gdev->srcu);
+		_guard.gc = srcu_dereference(_guard.gdev->chip,
+					     &_guard.gdev->srcu);
+
+		_guard;
+	     }),
+	     struct gpio_desc *desc)
+
 int gpiod_request(struct gpio_desc *desc, const char *label);
 void gpiod_free(struct gpio_desc *desc);
-int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
-		unsigned long lflags, enum gpiod_flags dflags);
-int gpiod_hog(struct gpio_desc *desc, const char *name,
-		unsigned long lflags, enum gpiod_flags dflags);
 
-/*
- * Return the GPIO number of the passed descriptor relative to its chip
- */
-static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
+static inline int gpiod_request_user(struct gpio_desc *desc, const char *label)
 {
-	return desc - &desc->gdev->descs[0];
-}
-
-void devprop_gpiochip_set_names(struct gpio_chip *chip);
+	int ret;
 
-/* With descriptor prefix */
+	ret = gpiod_request(desc, label);
+	if (ret == -EPROBE_DEFER)
+		ret = -ENODEV;
 
-#define gpiod_emerg(desc, fmt, ...)					       \
-	pr_emerg("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
-		 ##__VA_ARGS__)
-#define gpiod_crit(desc, fmt, ...)					       \
-	pr_crit("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
-		 ##__VA_ARGS__)
-#define gpiod_err(desc, fmt, ...)					       \
-	pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",  \
-		 ##__VA_ARGS__)
-#define gpiod_warn(desc, fmt, ...)					       \
-	pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
-		 ##__VA_ARGS__)
-#define gpiod_info(desc, fmt, ...)					       \
-	pr_info("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?", \
-		 ##__VA_ARGS__)
-#define gpiod_dbg(desc, fmt, ...)					       \
-	pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), desc->label ? : "?",\
-		 ##__VA_ARGS__)
+	return ret;
+}
 
-/* With chip prefix */
+struct gpio_desc *gpiod_find_and_request(struct device *consumer,
+					 struct fwnode_handle *fwnode,
+					 const char *con_id,
+					 unsigned int idx,
+					 enum gpiod_flags flags,
+					 const char *label,
+					 bool platform_lookup_allowed);
 
-#define chip_emerg(chip, fmt, ...)					\
-	dev_emerg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
-#define chip_crit(chip, fmt, ...)					\
-	dev_crit(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
-#define chip_err(chip, fmt, ...)					\
-	dev_err(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
-#define chip_warn(chip, fmt, ...)					\
-	dev_warn(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
-#define chip_info(chip, fmt, ...)					\
-	dev_info(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
-#define chip_dbg(chip, fmt, ...)					\
-	dev_dbg(&chip->gpiodev->dev, "(%s): " fmt, chip->label, ##__VA_ARGS__)
+int gpio_do_set_config(struct gpio_desc *desc, unsigned long config);
+int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
+		unsigned long lflags, enum gpiod_flags dflags);
+int gpio_set_debounce_timeout(struct gpio_desc *desc, unsigned int debounce);
+int gpiod_hog(struct gpio_desc *desc, const char *name,
+		unsigned long lflags, enum gpiod_flags dflags);
+int gpiochip_get_ngpios(struct gpio_chip *gc, struct device *dev);
+struct gpio_desc *gpiochip_get_desc(struct gpio_chip *gc, unsigned int hwnum);
+const char *gpiod_get_label(struct gpio_desc *desc);
 
-#ifdef CONFIG_GPIO_SYSFS
+/* With descriptor prefix */
 
-int gpiochip_sysfs_register(struct gpio_device *gdev);
-void gpiochip_sysfs_unregister(struct gpio_device *gdev);
+#define __gpiod_pr(level, desc, fmt, ...) \
+do { \
+	scoped_guard(srcu, &desc->gdev->desc_srcu) { \
+		pr_##level("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
+			   gpiod_get_label(desc) ?: "?", ##__VA_ARGS__); \
+	} \
+} while (0)
 
-#else
+#define gpiod_err(desc, fmt, ...) __gpiod_pr(err, desc, fmt, ##__VA_ARGS__)
+#define gpiod_warn(desc, fmt, ...) __gpiod_pr(warn, desc, fmt, ##__VA_ARGS__)
+#define gpiod_dbg(desc, fmt, ...) __gpiod_pr(debug, desc, fmt, ##__VA_ARGS__)
 
-static inline int gpiochip_sysfs_register(struct gpio_device *gdev)
-{
-	return 0;
-}
+/* With chip prefix */
 
-static inline void gpiochip_sysfs_unregister(struct gpio_device *gdev)
-{
-}
+#define __gpiochip_pr(level, gc, fmt, ...) \
+do { \
+	dev_##level(&gc->gpiodev->dev, "(%s): " fmt, gc->label, ##__VA_ARGS__); \
+} while (0)
 
-#endif /* CONFIG_GPIO_SYSFS */
+#define gpiochip_err(gc, fmt, ...) __gpiochip_pr(err, gc, fmt, ##__VA_ARGS__)
+#define gpiochip_warn(gc, fmt, ...) __gpiochip_pr(warn, gc, fmt, ##__VA_ARGS__)
+#define gpiochip_info(gc, fmt, ...) __gpiochip_pr(info, gc, fmt, ##__VA_ARGS__)
+#define gpiochip_dbg(gc, fmt, ...) __gpiochip_pr(dbg, gc, fmt, ##__VA_ARGS__)
 
 #endif /* GPIOLIB_H */