Merge tag 'gpio-v4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.18 development cycle.

  Core changes:

   - We have killed off VLA from the core library and all drivers.

     The background should be clear for everyone at this point:

        https://lwn.net/Articles/749064/

     Also I just don't like VLA's, kernel developers hate it when
     compilers do things behind their back. It's as simple as that.

     I'm sorry that they even slipped in to begin with. Kudos to Laura
     Abbott for exorcising them.

   - Support GPIO hogs in machines/board files.

  New drivers and chip support:

   - R-Car r8a77470 (RZ/G1C)

   - R-Car r8a77965 (M3-N)

   - R-Car r8a77990 (E3)

   - PCA953x driver improvements to accomodate more variants.

  Improvements and new features:

   - Support one interrupt per line on port A in the DesignWare dwapb
     driver.

  Misc:

   - Random cleanups, right header files in the drivers, some size
     optimizations etc"

* tag 'gpio-v4.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (73 commits)
  gpio: davinci: fix build warning when !CONFIG_OF
  gpio: dwapb: Fix rework support for 1 interrupt per port A GPIO
  gpio: pxa: Include the right header
  gpio: pl061: Include the right header
  gpio: pch: Include the right header
  gpio: pcf857x: Include the right header
  gpio: pca953x: Include the right header
  gpio: palmas: Include the right header
  gpio: omap: Include the right header
  gpio: octeon: Include the right header
  gpio: mxs: Switch to SPDX identifier
  gpio: Remove VLA from stmpe driver
  gpio: mxc: Switch to SPDX identifier
  gpio: mxc: add clock operation
  gpio: Remove VLA from gpiolib
  gpio: aspeed: Use a cache of output data registers
  gpio: aspeed: Set output latch before changing direction
  gpio: pca953x: fix address calculation for pcal6524
  gpio: pca953x: define masks for addressing common and extended registers
  gpio: pca953x: set the PCA_PCAL flag also when matching by DT
  ...

1 files changed, 126 insertions, 17 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 5dfd3c17fffc..e11a3bb03820 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -61,6 +61,11 @@ static struct bus_type gpio_bus_type = {
 	.name = "gpio",
 };
 
+/*
+ * Number of GPIOs to use for the fast path in set array
+ */
+#define FASTPATH_NGPIO CONFIG_GPIOLIB_FASTPATH_LIMIT
+
 /* gpio_lock prevents conflicts during gpio_desc[] table updates.
  * While any GPIO is requested, its gpio_chip is not removable;
  * each GPIO's "requested" flag serves as a lock and refcount.
@@ -71,6 +76,9 @@ static DEFINE_MUTEX(gpio_lookup_lock);
 static LIST_HEAD(gpio_lookup_list);
 LIST_HEAD(gpio_devices);
 
+static DEFINE_MUTEX(gpio_machine_hogs_mutex);
+static LIST_HEAD(gpio_machine_hogs);
+
 static void gpiochip_free_hogs(struct gpio_chip *chip);
 static int gpiochip_add_irqchip(struct gpio_chip *gpiochip,
 				struct lock_class_key *lock_key,
@@ -450,12 +458,11 @@ static long linehandle_ioctl(struct file *filep, unsigned int cmd,
 			vals[i] = !!ghd.values[i];
 
 		/* Reuse the array setting function */
-		gpiod_set_array_value_complex(false,
+		return gpiod_set_array_value_complex(false,
 					      true,
 					      lh->numdescs,
 					      lh->descs,
 					      vals);
-		return 0;
 	}
 	return -EINVAL;
 }
@@ -1172,6 +1179,41 @@ err_remove_device:
 	return status;
 }
 
+static void gpiochip_machine_hog(struct gpio_chip *chip, struct gpiod_hog *hog)
+{
+	struct gpio_desc *desc;
+	int rv;
+
+	desc = gpiochip_get_desc(chip, hog->chip_hwnum);
+	if (IS_ERR(desc)) {
+		pr_err("%s: unable to get GPIO desc: %ld\n",
+		       __func__, PTR_ERR(desc));
+		return;
+	}
+
+	if (test_bit(FLAG_IS_HOGGED, &desc->flags))
+		return;
+
+	rv = gpiod_hog(desc, hog->line_name, hog->lflags, hog->dflags);
+	if (rv)
+		pr_err("%s: unable to hog GPIO line (%s:%u): %d\n",
+		       __func__, chip->label, hog->chip_hwnum, rv);
+}
+
+static void machine_gpiochip_add(struct gpio_chip *chip)
+{
+	struct gpiod_hog *hog;
+
+	mutex_lock(&gpio_machine_hogs_mutex);
+
+	list_for_each_entry(hog, &gpio_machine_hogs, list) {
+		if (!strcmp(chip->label, hog->chip_label))
+			gpiochip_machine_hog(chip, hog);
+	}
+
+	mutex_unlock(&gpio_machine_hogs_mutex);
+}
+
 static void gpiochip_setup_devs(void)
 {
 	struct gpio_device *gdev;
@@ -1244,6 +1286,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
 		goto err_free_descs;
 	}
 
+	if (chip->ngpio > FASTPATH_NGPIO)
+		chip_warn(chip, "line cnt %u is greater than fast path cnt %u\n",
+		chip->ngpio, FASTPATH_NGPIO);
+
 	gdev->label = kstrdup_const(chip->label ?: "unknown", GFP_KERNEL);
 	if (!gdev->label) {
 		status = -ENOMEM;
@@ -1327,6 +1373,8 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
 
 	acpi_gpiochip_add(chip);
 
+	machine_gpiochip_add(chip);
+
 	/*
 	 * By first adding the chardev, and then adding the device,
 	 * we get a device node entry in sysfs under
@@ -2729,16 +2777,28 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep,
 
 	while (i < array_size) {
 		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)];
+		unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
+		unsigned long *mask, *bits;
 		int first, j, ret;
 
+		if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
+			mask = fastpath;
+		} else {
+			mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
+					   sizeof(*mask),
+					   can_sleep ? GFP_KERNEL : GFP_ATOMIC);
+			if (!mask)
+				return -ENOMEM;
+		}
+
+		bits = mask + BITS_TO_LONGS(chip->ngpio);
+		bitmap_zero(mask, chip->ngpio);
+
 		if (!can_sleep)
 			WARN_ON(chip->can_sleep);
 
 		/* collect all inputs belonging to the same chip */
 		first = i;
-		memset(mask, 0, sizeof(mask));
 		do {
 			const struct gpio_desc *desc = desc_array[i];
 			int hwgpio = gpio_chip_hwgpio(desc);
@@ -2749,8 +2809,11 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep,
 			 (desc_array[i]->gdev->chip == chip));
 
 		ret = gpio_chip_get_multiple(chip, mask, bits);
-		if (ret)
+		if (ret) {
+			if (mask != fastpath)
+				kfree(mask);
 			return ret;
+		}
 
 		for (j = first; j < i; j++) {
 			const struct gpio_desc *desc = desc_array[j];
@@ -2762,6 +2825,9 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep,
 			value_array[j] = value;
 			trace_gpio_value(desc_to_gpio(desc), 1, value);
 		}
+
+		if (mask != fastpath)
+			kfree(mask);
 	}
 	return 0;
 }
@@ -2945,7 +3011,7 @@ static void gpio_chip_set_multiple(struct gpio_chip *chip,
 	}
 }
 
-void gpiod_set_array_value_complex(bool raw, bool can_sleep,
+int gpiod_set_array_value_complex(bool raw, bool can_sleep,
 				   unsigned int array_size,
 				   struct gpio_desc **desc_array,
 				   int *value_array)
@@ -2954,14 +3020,26 @@ void gpiod_set_array_value_complex(bool raw, bool can_sleep,
 
 	while (i < array_size) {
 		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)];
+		unsigned long fastpath[2 * BITS_TO_LONGS(FASTPATH_NGPIO)];
+		unsigned long *mask, *bits;
 		int count = 0;
 
+		if (likely(chip->ngpio <= FASTPATH_NGPIO)) {
+			mask = fastpath;
+		} else {
+			mask = kmalloc_array(2 * BITS_TO_LONGS(chip->ngpio),
+					   sizeof(*mask),
+					   can_sleep ? GFP_KERNEL : GFP_ATOMIC);
+			if (!mask)
+				return -ENOMEM;
+		}
+
+		bits = mask + BITS_TO_LONGS(chip->ngpio);
+		bitmap_zero(mask, chip->ngpio);
+
 		if (!can_sleep)
 			WARN_ON(chip->can_sleep);
 
-		memset(mask, 0, sizeof(mask));
 		do {
 			struct gpio_desc *desc = desc_array[i];
 			int hwgpio = gpio_chip_hwgpio(desc);
@@ -2992,7 +3070,11 @@ void gpiod_set_array_value_complex(bool raw, bool can_sleep,
 		/* push collected bits to outputs */
 		if (count != 0)
 			gpio_chip_set_multiple(chip, mask, bits);
+
+		if (mask != fastpath)
+			kfree(mask);
 	}
+	return 0;
 }
 
 /**
@@ -3067,13 +3149,13 @@ EXPORT_SYMBOL_GPL(gpiod_set_value);
  * This function should be called from contexts where we cannot sleep, and will
  * complain if the GPIO chip functions potentially sleep.
  */
-void gpiod_set_raw_array_value(unsigned int array_size,
+int gpiod_set_raw_array_value(unsigned int array_size,
 			 struct gpio_desc **desc_array, int *value_array)
 {
 	if (!desc_array)
-		return;
-	gpiod_set_array_value_complex(true, false, array_size, desc_array,
-				      value_array);
+		return -EINVAL;
+	return gpiod_set_array_value_complex(true, false, array_size,
+					desc_array, value_array);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value);
 
@@ -3393,14 +3475,14 @@ EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
  *
  * This function is to be called from contexts that can sleep.
  */
-void gpiod_set_raw_array_value_cansleep(unsigned int array_size,
+int gpiod_set_raw_array_value_cansleep(unsigned int array_size,
 					struct gpio_desc **desc_array,
 					int *value_array)
 {
 	might_sleep_if(extra_checks);
 	if (!desc_array)
-		return;
-	gpiod_set_array_value_complex(true, true, array_size, desc_array,
+		return -EINVAL;
+	return gpiod_set_array_value_complex(true, true, array_size, desc_array,
 				      value_array);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_raw_array_value_cansleep);
@@ -3473,6 +3555,33 @@ void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
 }
 EXPORT_SYMBOL_GPL(gpiod_remove_lookup_table);
 
+/**
+ * gpiod_add_hogs() - register a set of GPIO hogs from machine code
+ * @hogs: table of gpio hog entries with a zeroed sentinel at the end
+ */
+void gpiod_add_hogs(struct gpiod_hog *hogs)
+{
+	struct gpio_chip *chip;
+	struct gpiod_hog *hog;
+
+	mutex_lock(&gpio_machine_hogs_mutex);
+
+	for (hog = &hogs[0]; hog->chip_label; hog++) {
+		list_add_tail(&hog->list, &gpio_machine_hogs);
+
+		/*
+		 * The chip may have been registered earlier, so check if it
+		 * exists and, if so, try to hog the line now.
+		 */
+		chip = find_chip_by_name(hog->chip_label);
+		if (chip)
+			gpiochip_machine_hog(chip, hog);
+	}
+
+	mutex_unlock(&gpio_machine_hogs_mutex);
+}
+EXPORT_SYMBOL_GPL(gpiod_add_hogs);
+
 static struct gpiod_lookup_table *gpiod_find_lookup_table(struct device *dev)
 {
 	const char *dev_id = dev ? dev_name(dev) : NULL;