Merge tag 'gpio-v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This time very little driver changes but lots of core changes.

  We have some interesting cooperative work for ARM and Intel alike,
  making the GPIO subsystem more and more suitable for industrial
  systems and the like, in addition to the in-kernel users.

  We touch driver core (device properties) and lib/* by adding one
  simple string array free function, these are authored by Andy
  Shevchenko who is a well known and recognized core helpers maintainers
  so this should be fine.

  We also see some Android GKI-related modularization in the MXC
  drivers.

  Core changes:

   - The big core change is the updated (v2) userspace character device
     API.

     This corrects badly designed 64-bit alignment around the line
     events. We also add the debounce request feature. This echoes the
     often quotes passage from Frederick Brooks "The mythical man-month"
     to always throw one away, which we have seen before in things such
     as V4L2. So we put in a new one and deprecate and obsolete the old
     one.

   - All example tools in tools/gpio/* are migrated to the new API to
     set a good example. The libgpiod userspace library has been
     augmented to use this new API pretty much from day 1.

   - Some misc API hardening by using strn* function calls has been
     added as well.

   - Use the simpler IDA interface for GPIO chip instance enumeration.

   - Add device core function for counting string arrays in device
     properties.

   - Provide a generic library function kfree_strarray() that can be
     used throughout the kernel.

  Driver enhancements:

   - The DesignWare dwapb-gpio driver has been enhanced and now uses the
     IRQ handling in the gpiolib core.

   - The mockup and aggregator drivers have seen some substantial code
     clean-up and now use more of the core kernel inftrastructure.

   - Misc cleanups using dev_err_probe().

   - The MXC drivers (Freescale/NXP) can now be built modularized, which
     makes modularized GKI Android kernels happy"

* tag 'gpio-v5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (73 commits)
  gpiolib: Update header block in gpiolib-cdev.h
  gpiolib: cdev: switch from kstrdup() to kstrndup()
  docs: gpio: add a new document to its index.rst
  gpio: pca953x: Add support for the NXP PCAL9554B/C
  tools: gpio: add debounce support to gpio-event-mon
  tools: gpio: add multi-line monitoring to gpio-event-mon
  tools: gpio: port gpio-event-mon to v2 uAPI
  tools: gpio: port gpio-hammer to v2 uAPI
  tools: gpio: rename nlines to num_lines
  tools: gpio: port gpio-watch to v2 uAPI
  tools: gpio: port lsgpio to v2 uAPI
  gpio: uapi: document uAPI v1 as deprecated
  gpiolib: cdev: support setting debounce
  gpiolib: cdev: support GPIO_V2_LINE_SET_VALUES_IOCTL
  gpiolib: cdev: support GPIO_V2_LINE_SET_CONFIG_IOCTL
  gpiolib: cdev: support edge detection for uAPI v2
  gpiolib: cdev: support GPIO_V2_GET_LINEINFO_IOCTL and GPIO_V2_GET_LINEINFO_WATCH_IOCTL
  gpiolib: cdev: support GPIO_V2_GET_LINE_IOCTL and GPIO_V2_LINE_GET_VALUES_IOCTL
  gpiolib: add build option for CDEV v1 ABI
  gpiolib: make cdev a build option
  ...

1 files changed, 66 insertions, 23 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 80137c1b3cdc..3cdf9effc13a 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -340,9 +340,6 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc)
 	struct gpio_device *gdev = gc->gpiodev;
 	int i;
 
-	if (!gc->names)
-		return 0;
-
 	/* First check all names if they are unique */
 	for (i = 0; i != gc->ngpio; ++i) {
 		struct gpio_desc *gpio;
@@ -361,6 +358,57 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc)
 	return 0;
 }
 
+/*
+ * devprop_gpiochip_set_names - Set GPIO line names using device properties
+ * @chip: GPIO chip whose lines should be named, if possible
+ *
+ * Looks for device property "gpio-line-names" and if it exists assigns
+ * GPIO line names for the chip. The memory allocated for the assigned
+ * names belong to the underlying software node and should not be released
+ * by the caller.
+ */
+static int devprop_gpiochip_set_names(struct gpio_chip *chip)
+{
+	struct gpio_device *gdev = chip->gpiodev;
+	struct device *dev = chip->parent;
+	const char **names;
+	int ret, i;
+	int count;
+
+	/* GPIO chip may not have a parent device whose properties we inspect. */
+	if (!dev)
+		return 0;
+
+	count = device_property_string_array_count(dev, "gpio-line-names");
+	if (count < 0)
+		return 0;
+
+	if (count > gdev->ngpio) {
+		dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d",
+			 count, gdev->ngpio);
+		count = gdev->ngpio;
+	}
+
+	names = kcalloc(count, sizeof(*names), GFP_KERNEL);
+	if (!names)
+		return -ENOMEM;
+
+	ret = device_property_read_string_array(dev, "gpio-line-names",
+						names, count);
+	if (ret < 0) {
+		dev_warn(&gdev->dev, "failed to read GPIO line names\n");
+		kfree(names);
+		return ret;
+	}
+
+	for (i = 0; i < count; i++)
+		gdev->descs[i].name = names[i];
+
+	kfree(names);
+
+	return 0;
+}
+
 static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc)
 {
 	unsigned long *p;
@@ -426,7 +474,7 @@ static void gpiodevice_release(struct device *dev)
 	struct gpio_device *gdev = dev_get_drvdata(dev);
 
 	list_del(&gdev->list);
-	ida_simple_remove(&gpio_ida, gdev->id);
+	ida_free(&gpio_ida, gdev->id);
 	kfree_const(gdev->label);
 	kfree(gdev->descs);
 	kfree(gdev);
@@ -537,7 +585,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 		gc->of_node = gdev->dev.of_node;
 #endif
 
-	gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);
+	gdev->id = ida_alloc(&gpio_ida, GFP_KERNEL);
 	if (gdev->id < 0) {
 		ret = gdev->id;
 		goto err_free_gdev;
@@ -621,7 +669,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
 	INIT_LIST_HEAD(&gdev->pin_ranges);
 #endif
 
-	ret = gpiochip_set_desc_names(gc);
+	if (gc->names)
+		ret = gpiochip_set_desc_names(gc);
+	else
+		ret = devprop_gpiochip_set_names(gc);
 	if (ret)
 		goto err_remove_from_list;
 
@@ -705,7 +756,7 @@ err_free_label:
 err_free_descs:
 	kfree(gdev->descs);
 err_free_ida:
-	ida_simple_remove(&gpio_ida, gdev->id);
+	ida_free(&gpio_ida, gdev->id);
 err_free_gdev:
 	/* failures here can mean systems won't boot... */
 	pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
@@ -2041,10 +2092,15 @@ static bool gpiod_free_commit(struct gpio_desc *desc)
 		clear_bit(FLAG_PULL_UP, &desc->flags);
 		clear_bit(FLAG_PULL_DOWN, &desc->flags);
 		clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
+		clear_bit(FLAG_EDGE_RISING, &desc->flags);
+		clear_bit(FLAG_EDGE_FALLING, &desc->flags);
 		clear_bit(FLAG_IS_HOGGED, &desc->flags);
 #ifdef CONFIG_OF_DYNAMIC
 		desc->hog = NULL;
 #endif
+#ifdef CONFIG_GPIO_CDEV
+		WRITE_ONCE(desc->debounce_period_us, 0);
+#endif
 		ret = true;
 	}
 
@@ -4402,31 +4458,18 @@ static int gpiolib_seq_show(struct seq_file *s, void *v)
 	return 0;
 }
 
-static const struct seq_operations gpiolib_seq_ops = {
+static const struct seq_operations gpiolib_sops = {
 	.start = gpiolib_seq_start,
 	.next = gpiolib_seq_next,
 	.stop = gpiolib_seq_stop,
 	.show = gpiolib_seq_show,
 };
-
-static int gpiolib_open(struct inode *inode, struct file *file)
-{
-	return seq_open(file, &gpiolib_seq_ops);
-}
-
-static const struct file_operations gpiolib_operations = {
-	.owner		= THIS_MODULE,
-	.open		= gpiolib_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= seq_release,
-};
+DEFINE_SEQ_ATTRIBUTE(gpiolib);
 
 static int __init gpiolib_debugfs_init(void)
 {
 	/* /sys/kernel/debug/gpio */
-	debugfs_create_file("gpio", S_IFREG | S_IRUGO, NULL, NULL,
-			    &gpiolib_operations);
+	debugfs_create_file("gpio", 0444, NULL, NULL, &gpiolib_fops);
 	return 0;
 }
 subsys_initcall(gpiolib_debugfs_init);