[4/6] gpio: reflect base and ngpio into gpio_device

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index de65633471af..c56309491e8b 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -180,7 +180,7 @@  static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
 	 *        Remove this redundant call (along with the corresponding
 	 *        unlock) when those drivers have been fixed.
 	 */
-	ret = gpiochip_lock_as_irq(desc->chip, gpio_chip_hwgpio(desc));
+	ret = gpiochip_lock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
 	if (ret < 0)
 		goto err_put_kn;
 
@@ -194,7 +194,7 @@  static int gpio_sysfs_request_irq(struct device *dev, unsigned char flags)
 	return 0;
 
 err_unlock:
-	gpiochip_unlock_as_irq(desc->chip, gpio_chip_hwgpio(desc));
+	gpiochip_unlock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
 err_put_kn:
 	sysfs_put(data->value_kn);
 
@@ -212,7 +212,7 @@  static void gpio_sysfs_free_irq(struct device *dev)
 
 	data->irq_flags = 0;
 	free_irq(data->irq, data);
-	gpiochip_unlock_as_irq(desc->chip, gpio_chip_hwgpio(desc));
+	gpiochip_unlock_as_irq(desc->gdev->chip, gpio_chip_hwgpio(desc));
 	sysfs_put(data->value_kn);
 }
 
@@ -566,8 +566,8 @@  int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
 		return -EINVAL;
 	}
 
-	chip = desc->chip;
-	gdev = chip->gpiodev;
+	gdev = desc->gdev;
+	chip = gdev->chip;
 
 	mutex_lock(&sysfs_lock);
 
@@ -765,7 +765,7 @@  void gpiochip_sysfs_unregister(struct gpio_device *gdev)
 
 	/* unregister gpiod class devices owned by sysfs */
 	for (i = 0; i < chip->ngpio; i++) {
-		desc = &chip->gpiodev->descs[i];
+		desc = &gdev->descs[i];
 		if (test_and_clear_bit(FLAG_SYSFS, &desc->flags))
 			gpiod_free(desc);
 	}
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index f3fcd415a77b..cbc9c764a7fb 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -85,10 +85,10 @@  struct gpio_desc *gpio_to_desc(unsigned gpio)
 	spin_lock_irqsave(&gpio_lock, flags);
 
 	list_for_each_entry(gdev, &gpio_devices, list) {
-		if (gdev->chip->base <= gpio &&
-		    gdev->chip->base + gdev->chip->ngpio > gpio) {
+		if (gdev->base <= gpio &&
+		    gdev->base + gdev->ngpio > gpio) {
 			spin_unlock_irqrestore(&gpio_lock, flags);
-			return &gdev->descs[gpio - gdev->chip->base];
+			return &gdev->descs[gpio - gdev->base];
 		}
 	}
 
@@ -107,10 +107,12 @@  EXPORT_SYMBOL_GPL(gpio_to_desc);
 struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
 				    u16 hwnum)
 {
-	if (hwnum >= chip->ngpio)
+	struct gpio_device *gdev = chip->gpiodev;
+
+	if (hwnum >= gdev->ngpio)
 		return ERR_PTR(-EINVAL);
 
-	return &chip->gpiodev->descs[hwnum];
+	return &gdev->descs[hwnum];
 }
 
 /**
@@ -120,7 +122,7 @@  struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip,
  */
 int desc_to_gpio(const struct gpio_desc *desc)
 {
-	return desc->chip->base + (desc - &desc->chip->gpiodev->descs[0]);
+	return desc->gdev->base + (desc - &desc->gdev->descs[0]);
 }
 EXPORT_SYMBOL_GPL(desc_to_gpio);
 
@@ -131,7 +133,9 @@  EXPORT_SYMBOL_GPL(desc_to_gpio);
  */
 struct gpio_chip *gpiod_to_chip(const struct gpio_desc *desc)
 {
-	return desc ? desc->chip : NULL;
+	if (!desc || !desc->gdev || !desc->gdev->chip)
+		return NULL;
+	return desc->gdev->chip;
 }
 EXPORT_SYMBOL_GPL(gpiod_to_chip);
 
@@ -143,11 +147,11 @@  static int gpiochip_find_base(int ngpio)
 
 	list_for_each_entry_reverse(gdev, &gpio_devices, list) {
 		/* found a free space? */
-		if (gdev->chip->base + gdev->chip->ngpio <= base)
+		if (gdev->base + gdev->ngpio <= base)
 			break;
 		else
 			/* nope, check the space right before the chip */
-			base = gdev->chip->base - ngpio;
+			base = gdev->base - ngpio;
 	}
 
 	if (gpio_is_valid(base)) {
@@ -214,14 +218,7 @@  static int gpiodev_add_to_list(struct gpio_device *gdev)
 	}
 
 	list_for_each_entry(iterator, &gpio_devices, list) {
-		/*
-		 * The list may contain dangling GPIO devices with no
-		 * live chip assigned.
-		 */
-		if (!iterator->chip)
-			continue;
-		if (iterator->chip->base >=
-		    gdev->chip->base + gdev->chip->ngpio) {
+		if (iterator->base >= gdev->base + gdev->ngpio) {
 			/*
 			 * Iterator is the first GPIO chip so there is no
 			 * previous one
@@ -234,8 +231,8 @@  static int gpiodev_add_to_list(struct gpio_device *gdev)
 				 * [base, base + ngpio - 1]) between previous
 				 * and iterator chip.
 				 */
-				if (previous->chip->base + previous->chip->ngpio
-						<= gdev->chip->base)
+				if (previous->base + previous->ngpio
+				    <= gdev->base)
 					goto found;
 			}
 		}
@@ -249,7 +246,7 @@  static int gpiodev_add_to_list(struct gpio_device *gdev)
 	 */
 
 	iterator = list_last_entry(&gpio_devices, struct gpio_device, list);
-	if (iterator->chip->base + iterator->chip->ngpio <= gdev->chip->base) {
+	if (iterator->base + iterator->ngpio <= gdev->base) {
 		list_add(&gdev->list, &iterator->list);
 		return 0;
 	}
@@ -276,15 +273,15 @@  static struct gpio_desc *gpio_name_to_desc(const char * const name)
 	list_for_each_entry(gdev, &gpio_devices, list) {
 		int i;
 
-		for (i = 0; i != gdev->chip->ngpio; ++i) {
-			struct gpio_desc *gpio = &gdev->descs[i];
+		for (i = 0; i != gdev->ngpio; ++i) {
+			struct gpio_desc *desc = &gdev->descs[i];
 
-			if (!gpio->name || !name)
+			if (!desc->name || !name)
 				continue;
 
-			if (!strcmp(gpio->name, name)) {
+			if (!strcmp(desc->name, name)) {
 				spin_unlock_irqrestore(&gpio_lock, flags);
-				return gpio;
+				return desc;
 			}
 		}
 	}
@@ -302,6 +299,7 @@  static struct gpio_desc *gpio_name_to_desc(const char * const name)
  */
 static int gpiochip_set_desc_names(struct gpio_chip *gc)
 {
+	struct gpio_device *gdev = gc->gpiodev;
 	int i;
 
 	if (!gc->names)
@@ -313,14 +311,14 @@  static int gpiochip_set_desc_names(struct gpio_chip *gc)
 
 		gpio = gpio_name_to_desc(gc->names[i]);
 		if (gpio)
-			dev_warn(&gc->gpiodev->dev,
+			dev_warn(&gdev->dev,
 				 "Detected name collision for GPIO name '%s'\n",
 				 gc->names[i]);
 	}
 
 	/* Then add all names to the GPIO descriptors */
 	for (i = 0; i != gc->ngpio; ++i)
-		gc->gpiodev->descs[i].name = gc->names[i];
+		gdev->descs[i].name = gc->names[i];
 
 	return 0;
 }
@@ -344,7 +342,7 @@  static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		strncpy(chipinfo.name, dev_name(&gdev->dev),
 			sizeof(chipinfo.name));
 		chipinfo.name[sizeof(chipinfo.name)-1] = '\0';
-		chipinfo.lines = chip->ngpio;
+		chipinfo.lines = gdev->ngpio;
 		if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
 			return -EFAULT;
 		return 0;
@@ -476,17 +474,24 @@  int gpiochip_add_data(struct gpio_chip *chip, void *data)
 		goto err_free_gdev;
 	}
 
-	/* FIXME: move driver data into gpio_device dev_set_drvdata() */
-	chip->data = data;
-
 	if (chip->ngpio == 0) {
 		chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
 		status = -EINVAL;
 		goto err_free_gdev;
 	}
+	gdev->ngpio = chip->ngpio;
+	/* FIXME: move driver data into gpio_device dev_set_drvdata() */
+	chip->data = data;
 
 	spin_lock_irqsave(&gpio_lock, flags);
 
+	/*
+	 * TODO: this allocates a Linux GPIO number base in the global
+	 * GPIO numberspace for this chip. In the long run we want to
+	 * get *rid* of this numberspace and use only descriptors, but
+	 * it may be a pipe dream. It will not happen before we get rid
+	 * of the sysfs interface anyways.
+	 */
 	if (base < 0) {
 		base = gpiochip_find_base(chip->ngpio);
 		if (base < 0) {
@@ -494,8 +499,15 @@  int gpiochip_add_data(struct gpio_chip *chip, void *data)
 			spin_unlock_irqrestore(&gpio_lock, flags);
 			goto err_free_gdev;
 		}
+		/*
+		 * TODO: it should not be necessary to reflect the assigned
+		 * base outside of the GPIO subsystem. Go over drivers and
+		 * see if anyone makes use of this, else drop this and assign
+		 * a poison instead.
+		 */
 		chip->base = base;
 	}
+	gdev->base = base;
 
 	status = gpiodev_add_to_list(gdev);
 	if (status) {
@@ -506,8 +518,7 @@  int gpiochip_add_data(struct gpio_chip *chip, void *data)
 	for (i = 0; i < chip->ngpio; i++) {
 		struct gpio_desc *desc = &gdev->descs[i];
 
-		/* REVISIT: maybe a pointer to gpio_device is better */
-		desc->chip = chip;
+		desc->gdev = gdev;
 
 		/* REVISIT: most hardware initializes GPIOs as inputs (often
 		 * with pullups enabled) so power usage is minimized. Linux
@@ -563,9 +574,9 @@  int gpiochip_add_data(struct gpio_chip *chip, void *data)
 	/* From this point, the .release() function cleans up gpio_device */
 	gdev->dev.release = gpiodevice_release;
 	get_device(&gdev->dev);
-	pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__,
-		chip->base, chip->base + chip->ngpio - 1,
-		chip->label ? : "generic");
+	pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
+		 __func__, gdev->base, gdev->base + gdev->ngpio - 1,
+		 dev_name(&gdev->dev), chip->label ? : "generic");
 
 	return 0;
 
@@ -586,8 +597,8 @@  err_free_gdev:
 	kfree(gdev);
 	/* failures here can mean systems won't boot... */
 	pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
-		chip->base, chip->base + chip->ngpio - 1,
-		chip->label ? : "generic");
+	       gdev->base, gdev->base + gdev->ngpio - 1,
+	       chip->label ? : "generic");
 	return status;
 }
 EXPORT_SYMBOL_GPL(gpiochip_add_data);
@@ -618,16 +629,15 @@  void gpiochip_remove(struct gpio_chip *chip)
 	of_gpiochip_remove(chip);
 
 	spin_lock_irqsave(&gpio_lock, flags);
-	for (i = 0; i < chip->ngpio; i++) {
+	for (i = 0; i < gdev->ngpio; i++) {
 		desc = &gdev->descs[i];
-		desc->chip = NULL;
 		if (test_bit(FLAG_REQUESTED, &desc->flags))
 			requested = true;
 	}
 	spin_unlock_irqrestore(&gpio_lock, flags);
 
 	if (requested)
-		dev_crit(&chip->gpiodev->dev,
+		dev_crit(&gdev->dev,
 			 "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
 
 	/*
@@ -967,7 +977,7 @@  static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
  */
 int gpiochip_generic_request(struct gpio_chip *chip, unsigned offset)
 {
-	return pinctrl_request_gpio(chip->base + offset);
+	return pinctrl_request_gpio(chip->gpiodev->base + offset);
 }
 EXPORT_SYMBOL_GPL(gpiochip_generic_request);
 
@@ -978,7 +988,7 @@  EXPORT_SYMBOL_GPL(gpiochip_generic_request);
  */
 void gpiochip_generic_free(struct gpio_chip *chip, unsigned offset)
 {
-	pinctrl_free_gpio(chip->base + offset);
+	pinctrl_free_gpio(chip->gpiodev->base + offset);
 }
 EXPORT_SYMBOL_GPL(gpiochip_generic_free);
 
@@ -996,6 +1006,7 @@  int gpiochip_add_pingroup_range(struct gpio_chip *chip,
 			unsigned int gpio_offset, const char *pin_group)
 {
 	struct gpio_pin_range *pin_range;
+	struct gpio_device *gdev = chip->gpiodev;
 	int ret;
 
 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
@@ -1008,7 +1019,7 @@  int gpiochip_add_pingroup_range(struct gpio_chip *chip,
 	pin_range->range.id = gpio_offset;
 	pin_range->range.gc = chip;
 	pin_range->range.name = chip->label;
-	pin_range->range.base = chip->base + gpio_offset;
+	pin_range->range.base = gdev->base + gpio_offset;
 	pin_range->pctldev = pctldev;
 
 	ret = pinctrl_get_group_pins(pctldev, pin_group,
@@ -1045,6 +1056,7 @@  int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
 			   unsigned int npins)
 {
 	struct gpio_pin_range *pin_range;
+	struct gpio_device *gdev = chip->gpiodev;
 	int ret;
 
 	pin_range = kzalloc(sizeof(*pin_range), GFP_KERNEL);
@@ -1057,7 +1069,7 @@  int gpiochip_add_pin_range(struct gpio_chip *chip, const char *pinctl_name,
 	pin_range->range.id = gpio_offset;
 	pin_range->range.gc = chip;
 	pin_range->range.name = chip->label;
-	pin_range->range.base = chip->base + gpio_offset;
+	pin_range->range.base = gdev->base + gpio_offset;
 	pin_range->range.pin_base = pin_offset;
 	pin_range->range.npins = npins;
 	pin_range->pctldev = pinctrl_find_and_add_gpio_range(pinctl_name,
@@ -1104,7 +1116,7 @@  EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges);
  */
 static int __gpiod_request(struct gpio_desc *desc, const char *label)
 {
-	struct gpio_chip	*chip = desc->chip;
+	struct gpio_chip	*chip = desc->gdev->chip;
 	int			status;
 	unsigned long		flags;
 
@@ -1153,27 +1165,48 @@  done:
 	return status;
 }
 
+/*
+ * This descriptor validation needs to be inserted verbatim into each
+ * function taking a descriptor, so we need to use a preprocessor
+ * macro to avoid endless duplication.
+ */
+#define VALIDATE_DESC(desc) do { \
+	if (!desc || !desc->gdev) { \
+		pr_warn("%s: invalid GPIO\n", __func__); \
+		return -EINVAL; \
+	} \
+	if ( !desc->gdev->chip ) { \
+		dev_warn(&desc->gdev->dev, \
+			 "%s: backing chip is gone\n", __func__); \
+		return 0; \
+	} } while (0)
+
+#define VALIDATE_DESC_VOID(desc) do { \
+	if (!desc || !desc->gdev) { \
+		pr_warn("%s: invalid GPIO\n", __func__); \
+		return; \
+	} \
+	if (!desc->gdev->chip) { \
+		dev_warn(&desc->gdev->dev, \
+			 "%s: backing chip is gone\n", __func__); \
+		return; \
+	} } while (0)
+
+
 int gpiod_request(struct gpio_desc *desc, const char *label)
 {
 	int status = -EPROBE_DEFER;
-	struct gpio_chip *chip;
-
-	if (!desc) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	struct gpio_device *gdev;
 
-	chip = desc->chip;
-	if (!chip)
-		goto done;
+	VALIDATE_DESC(desc);
+	gdev = desc->gdev;
 
-	if (try_module_get(chip->gpiodev->owner)) {
+	if (try_module_get(gdev->owner)) {
 		status = __gpiod_request(desc, label);
 		if (status < 0)
-			module_put(chip->gpiodev->owner);
+			module_put(gdev->owner);
 	}
 
-done:
 	if (status)
 		gpiod_dbg(desc, "%s: status %d\n", __func__, status);
 
@@ -1192,7 +1225,7 @@  static bool __gpiod_free(struct gpio_desc *desc)
 
 	spin_lock_irqsave(&gpio_lock, flags);
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	if (chip && test_bit(FLAG_REQUESTED, &desc->flags)) {
 		if (chip->free) {
 			spin_unlock_irqrestore(&gpio_lock, flags);
@@ -1216,7 +1249,7 @@  static bool __gpiod_free(struct gpio_desc *desc)
 void gpiod_free(struct gpio_desc *desc)
 {
 	if (desc && __gpiod_free(desc))
-		module_put(desc->chip->gpiodev->owner);
+		module_put(desc->gdev->owner);
 	else
 		WARN_ON(extra_checks);
 }
@@ -1293,7 +1326,8 @@  void gpiochip_free_own_desc(struct gpio_desc *desc)
 }
 EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
 
-/* Drivers MUST set GPIO direction before making get/set calls.  In
+/*
+ * Drivers MUST set GPIO direction before making get/set calls.  In
  * some cases this is done in early boot, before IRQs are enabled.
  *
  * As a rule these aren't called more than once (except for drivers
@@ -1316,12 +1350,9 @@  int gpiod_direction_input(struct gpio_desc *desc)
 	struct gpio_chip	*chip;
 	int			status = -EINVAL;
 
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	VALIDATE_DESC(desc);
+	chip = desc->gdev->chip;
 
-	chip = desc->chip;
 	if (!chip->get || !chip->direction_input) {
 		gpiod_warn(desc,
 			"%s: missing get() or direction_input() operations\n",
@@ -1360,7 +1391,7 @@  static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
 	if (!value && test_bit(FLAG_OPEN_SOURCE,  &desc->flags))
 		return gpiod_direction_input(desc);
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	if (!chip->set || !chip->direction_output) {
 		gpiod_warn(desc,
 		       "%s: missing set() or direction_output() operations\n",
@@ -1389,10 +1420,7 @@  static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
  */
 int gpiod_direction_output_raw(struct gpio_desc *desc, int value)
 {
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	VALIDATE_DESC(desc);
 	return _gpiod_direction_output_raw(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
@@ -1411,10 +1439,7 @@  EXPORT_SYMBOL_GPL(gpiod_direction_output_raw);
  */
 int gpiod_direction_output(struct gpio_desc *desc, int value)
 {
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
+	VALIDATE_DESC(desc);
 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 		value = !value;
 	return _gpiod_direction_output_raw(desc, value);
@@ -1433,12 +1458,8 @@  int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
 {
 	struct gpio_chip	*chip;
 
-	if (!desc || !desc->chip) {
-		pr_warn("%s: invalid GPIO\n", __func__);
-		return -EINVAL;
-	}
-
-	chip = desc->chip;
+	VALIDATE_DESC(desc);
+	chip = desc->gdev->chip;
 	if (!chip->set || !chip->set_debounce) {
 		gpiod_dbg(desc,
 			  "%s: missing set() or set_debounce() operations\n",
@@ -1458,6 +1479,7 @@  EXPORT_SYMBOL_GPL(gpiod_set_debounce);
  */
 int gpiod_is_active_low(const struct gpio_desc *desc)
 {
+	VALIDATE_DESC(desc);
 	return test_bit(FLAG_ACTIVE_LOW, &desc->flags);
 }
 EXPORT_SYMBOL_GPL(gpiod_is_active_low);
@@ -1490,7 +1512,7 @@  static int _gpiod_get_raw_value(const struct gpio_desc *desc)
 	int offset;
 	int value;
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	offset = gpio_chip_hwgpio(desc);
 	value = chip->get ? chip->get(chip, offset) : -EIO;
 	value = value < 0 ? value : !!value;
@@ -1510,10 +1532,9 @@  static int _gpiod_get_raw_value(const struct gpio_desc *desc)
  */
 int gpiod_get_raw_value(const struct gpio_desc *desc)
 {
-	if (!desc)
-		return 0;
+	VALIDATE_DESC(desc);
 	/* Should be using gpio_get_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 	return _gpiod_get_raw_value(desc);
 }
 EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
@@ -1531,10 +1552,10 @@  EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
 int gpiod_get_value(const struct gpio_desc *desc)
 {
 	int value;
-	if (!desc)
-		return 0;
+
+	VALIDATE_DESC(desc);
 	/* Should be using gpio_get_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 
 	value = _gpiod_get_raw_value(desc);
 	if (value < 0)
@@ -1555,7 +1576,7 @@  EXPORT_SYMBOL_GPL(gpiod_get_value);
 static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value)
 {
 	int err = 0;
-	struct gpio_chip *chip = desc->chip;
+	struct gpio_chip *chip = desc->gdev->chip;
 	int offset = gpio_chip_hwgpio(desc);
 
 	if (value) {
@@ -1582,7 +1603,7 @@  static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value)
 static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value)
 {
 	int err = 0;
-	struct gpio_chip *chip = desc->chip;
+	struct gpio_chip *chip = desc->gdev->chip;
 	int offset = gpio_chip_hwgpio(desc);
 
 	if (value) {
@@ -1605,7 +1626,7 @@  static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value)
 {
 	struct gpio_chip	*chip;
 
-	chip = desc->chip;
+	chip = desc->gdev->chip;
 	trace_gpio_value(desc_to_gpio(desc), 0, value);
 	if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
 		_gpio_set_open_drain_value(desc, value);
@@ -1653,7 +1674,7 @@  static void gpiod_set_array_value_priv(bool raw, bool can_sleep,
 	int i = 0;
 
 	while (i < array_size) {
-		struct gpio_chip *chip = desc_array[i]->chip;
+		struct gpio_chip *chip = desc_array[i]->gdev->chip;
 		unsigned long mask[BITS_TO_LONGS(chip->ngpio)];
 		unsigned long bits[BITS_TO_LONGS(chip->ngpio)];
 		int count = 0;
@@ -1687,7 +1708,8 @@  static void gpiod_set_array_value_priv(bool raw, bool can_sleep,
 				count++;
 			}
 			i++;
-		} while ((i < array_size) && (desc_array[i]->chip == chip));
+		} while ((i < array_size) &&
+			 (desc_array[i]->gdev->chip == chip));
 		/* push collected bits to outputs */
 		if (count != 0)
 			gpio_chip_set_multiple(chip, mask, bits);
@@ -1707,10 +1729,9 @@  static void gpiod_set_array_value_priv(bool raw, bool can_sleep,
  */
 void gpiod_set_raw_value(struct gpio_desc *desc, int value)
 {
-	if (!desc)
-		return;
+	VALIDATE_DESC_VOID(desc);
 	/* Should be using gpio_set_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 	_gpiod_set_raw_value(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
@@ -1728,10 +1749,9 @@  EXPORT_SYMBOL_GPL(gpiod_set_raw_value);
  */
 void gpiod_set_value(struct gpio_desc *desc, int value)
 {
-	if (!desc)
-		return;
+	VALIDATE_DESC_VOID(desc);
 	/* Should be using gpio_set_value_cansleep() */
-	WARN_ON(desc->chip->can_sleep);
+	WARN_ON(desc->gdev->chip->can_sleep);
 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 		value = !value;
 	_gpiod_set_raw_value(desc, value);
@@ -1789,9 +1809,8 @@  EXPORT_SYMBOL_GPL(gpiod_set_array_value);
  */
 int gpiod_cansleep(const struct gpio_desc *desc)
 {
-	if (!desc)
-		return 0;
-	return desc->chip->can_sleep;
+	VALIDATE_DESC(desc);
+	return desc->gdev->chip->can_sleep;
 }
 EXPORT_SYMBOL_GPL(gpiod_cansleep);
 
@@ -1807,9 +1826,8 @@  int gpiod_to_irq(const struct gpio_desc *desc)
 	struct gpio_chip	*chip;
 	int			offset;
 
-	if (!desc)
-		return -EINVAL;
-	chip = desc->chip;
+	VALIDATE_DESC(desc);
+	chip = desc->gdev->chip;
 	offset = gpio_chip_hwgpio(desc);
 	return chip->to_irq ? chip->to_irq(chip, offset) : -ENXIO;
 }
@@ -1869,8 +1887,7 @@  EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
 int gpiod_get_raw_value_cansleep(const struct gpio_desc *desc)
 {
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return 0;
+	VALIDATE_DESC(desc);
 	return _gpiod_get_raw_value(desc);
 }
 EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
@@ -1889,9 +1906,7 @@  int gpiod_get_value_cansleep(const struct gpio_desc *desc)
 	int value;
 
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return 0;
-
+	VALIDATE_DESC(desc);
 	value = _gpiod_get_raw_value(desc);
 	if (value < 0)
 		return value;
@@ -1916,8 +1931,7 @@  EXPORT_SYMBOL_GPL(gpiod_get_value_cansleep);
 void gpiod_set_raw_value_cansleep(struct gpio_desc *desc, int value)
 {
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return;
+	VALIDATE_DESC_VOID(desc);
 	_gpiod_set_raw_value(desc, value);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
@@ -1935,9 +1949,7 @@  EXPORT_SYMBOL_GPL(gpiod_set_raw_value_cansleep);
 void gpiod_set_value_cansleep(struct gpio_desc *desc, int value)
 {
 	might_sleep_if(extra_checks);
-	if (!desc)
-		return;
-
+	VALIDATE_DESC_VOID(desc);
 	if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
 		value = !value;
 	_gpiod_set_raw_value(desc, value);
@@ -2660,15 +2672,16 @@  core_initcall(gpiolib_dev_init);
 
 #ifdef CONFIG_DEBUG_FS
 
-static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
 {
 	unsigned		i;
-	unsigned		gpio = chip->base;
-	struct gpio_desc	*gdesc = &chip->gpiodev->descs[0];
+	struct gpio_chip	*chip = gdev->chip;
+	unsigned		gpio = gdev->base;
+	struct gpio_desc	*gdesc = &gdev->descs[0];
 	int			is_out;
 	int			is_irq;
 
-	for (i = 0; i < chip->ngpio; i++, gpio++, gdesc++) {
+	for (i = 0; i < gdev->ngpio; i++, gpio++, gdesc++) {
 		if (!test_bit(FLAG_REQUESTED, &gdesc->flags)) {
 			if (gdesc->name) {
 				seq_printf(s, " gpio-%-3d (%-20.20s)\n",
@@ -2747,7 +2760,7 @@  static int gpiolib_seq_show(struct seq_file *s, void *v)
 
 	seq_printf(s, "%s%s: GPIOs %d-%d", (char *)s->private,
 		   dev_name(&gdev->dev),
-		   chip->base, chip->base + chip->ngpio - 1);
+		   gdev->base, gdev->base + gdev->ngpio - 1);
 	parent = chip->parent;
 	if (parent)
 		seq_printf(s, ", parent: %s/%s",
@@ -2762,7 +2775,7 @@  static int gpiolib_seq_show(struct seq_file *s, void *v)
 	if (chip->dbg_show)
 		chip->dbg_show(s, chip);
 	else
-		gpiolib_dbg_show(s, chip);
+		gpiolib_dbg_show(s, gdev);
 
 	return 0;
 }
diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index 39b8301c98b6..d154984c71d9 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -33,6 +33,10 @@  struct acpi_device;
  * @chip: pointer to the corresponding gpiochip, holding static
  * data for this device
  * @descs: array of ngpio descriptors.
+ * @ngpio: the number of GPIO lines on this GPIO device, equal to the size
+ * of the @descs array.
+ * @base: GPIO base in the DEPRECATED global Linux GPIO numberspace, assigned
+ * at device creation time.
  * @list: links gpio_device:s together for traversal
  *
  * This state container holds most of the runtime variable data
@@ -48,6 +52,8 @@  struct gpio_device {
 	struct module		*owner;
 	struct gpio_chip	*chip;
 	struct gpio_desc	*descs;
+	int			base;
+	u16			ngpio;
 	struct list_head        list;
 };
 
@@ -125,7 +131,7 @@  extern struct spinlock gpio_lock;
 extern struct list_head gpio_devices;
 
 struct gpio_desc {
-	struct gpio_chip	*chip;
+	struct gpio_device	*gdev;
 	unsigned long		flags;
 /* flag symbols are bit numbers */
 #define FLAG_REQUESTED	0
@@ -154,7 +160,7 @@  int gpiod_hog(struct gpio_desc *desc, const char *name,
  */
 static int __maybe_unused gpio_chip_hwgpio(const struct gpio_desc *desc)
 {
-	return desc - &desc->chip->gpiodev->descs[0];
+	return desc - &desc->gdev->descs[0];
 }
 
 /* With descriptor prefix */