Merge tag 'gpio-fixes-for-v5.8-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into fixes

gpio fixes for v5.8-rc3

- several fixes for gpio-pca953x

1 files changed, 94 insertions, 5 deletions

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 1fca8dd7824f..a3b9bdedbe44 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -107,6 +107,84 @@ 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, },
 	{ }
@@ -322,6 +400,7 @@ 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,
 };
@@ -623,8 +702,6 @@ 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);
@@ -635,7 +712,11 @@ 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 */
@@ -734,14 +815,16 @@ 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)
@@ -752,6 +835,12 @@ 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;