gpio: Pass a flag to gpiochip_request_own_desc()

Before things go out of hand, make it possible to pass
flags when requesting "own" descriptors from a gpio_chip.
This is necessary if the chip wants to request a GPIO with
active low semantics, for example.

Cc: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Roger Quadros <rogerq@ti.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Documentation/driver-api/gpio/driver.rst

@@ -434,7 +434,9 @@ try_module_get()). A GPIO driver can use the following functions instead
 to request and free descriptors without being pinned to the kernel forever::
 
 	struct gpio_desc *gpiochip_request_own_desc(struct gpio_desc *desc,
-						    const char *label)
+						    u16 hwnum,
+						    const char *label,
+						    enum gpiod_flags flags)
 
 	void gpiochip_free_own_desc(struct gpio_desc *desc)
 

arch/arm/mach-omap1/ams-delta-fiq.c

@@ -103,7 +103,7 @@ void __init ams_delta_init_fiq(struct gpio_chip *chip,
 	}
 
 	for (i = 0; i < ARRAY_SIZE(irq_data); i++) {
-		gpiod = gpiochip_request_own_desc(chip, i, pin_name[i]);
+		gpiod = gpiochip_request_own_desc(chip, i, pin_name[i], 0);
 		if (IS_ERR(gpiod)) {
 			pr_err("%s: failed to get GPIO pin %d (%ld)\n",
 			       __func__, i, PTR_ERR(gpiod));

arch/arm/mach-omap1/board-ams-delta.c

@@ -808,7 +808,7 @@ static void __init ams_delta_led_init(struct gpio_chip *chip)
 	int i;
 
 	for (i = LATCH1_PIN_LED_CAMERA; i < LATCH1_PIN_DOCKIT1; i++) {
-		gpiod = gpiochip_request_own_desc(chip, i, NULL);
+		gpiod = gpiochip_request_own_desc(chip, i, "camera-led", 0);
 		if (IS_ERR(gpiod)) {
 			pr_warn("%s: %s GPIO %d request failed (%ld)\n",
 				__func__, LATCH1_LABEL, i, PTR_ERR(gpiod));

drivers/gpio/gpio-mvebu.c

@@ -608,7 +608,7 @@ static int mvebu_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
 		ret = -EBUSY;
 	} else {
 		desc = gpiochip_request_own_desc(&mvchip->chip,
-						 pwm->hwpwm, "mvebu-pwm");
+						 pwm->hwpwm, "mvebu-pwm", 0);
 		if (IS_ERR(desc)) {
 			ret = PTR_ERR(desc);
 			goto out;

drivers/gpio/gpiolib-acpi.c

@@ -167,7 +167,7 @@ static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
 	if (!handler)
 		return AE_OK;
 
-	desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
+	desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event", 0);
 	if (IS_ERR(desc)) {
 		dev_err(chip->parent, "Failed to request GPIO\n");
 		return AE_ERROR;
@@ -884,21 +884,14 @@ acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
 			const char *label = "ACPI:OpRegion";
 			int err;
 
-			desc = gpiochip_request_own_desc(chip, pin, label);
+			desc = gpiochip_request_own_desc(chip, pin, label,
+							 flags);
 			if (IS_ERR(desc)) {
 				status = AE_ERROR;
 				mutex_unlock(&achip->conn_lock);
 				goto out;
 			}
 
-			err = gpiod_configure_flags(desc, label, 0, flags);
-			if (err < 0) {
-				status = AE_NOT_CONFIGURED;
-				gpiochip_free_own_desc(desc);
-				mutex_unlock(&achip->conn_lock);
-				goto out;
-			}
-
 			conn = kzalloc(sizeof(*conn), GFP_KERNEL);
 			if (!conn) {
 				status = AE_NO_MEMORY;

drivers/gpio/gpiolib.c

@@ -2454,6 +2454,7 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested);
  * @chip: GPIO chip
  * @hwnum: hardware number of the GPIO for which to request the descriptor
  * @label: label for the GPIO
+ * @flags: flags for this GPIO or 0 if default
  *
  * Function allows GPIO chip drivers to request and use their own GPIO
  * descriptors via gpiolib API. Difference to gpiod_request() is that this
@@ -2466,7 +2467,8 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested);
  * code on failure.
  */
 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
-					    const char *label)
+					    const char *label,
+					    enum gpiod_flags flags)
 {
 	struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
 	int err;
@@ -2480,6 +2482,13 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
 	if (err < 0)
 		return ERR_PTR(err);
 
+	err = gpiod_configure_flags(desc, label, 0, flags);
+	if (err) {
+		chip_err(chip, "setup of own GPIO %s failed\n", label);
+		gpiod_free_commit(desc);
+		return ERR_PTR(err);
+	}
+
 	return desc;
 }
 EXPORT_SYMBOL_GPL(gpiochip_request_own_desc);
@@ -4332,7 +4341,15 @@ int gpiod_hog(struct gpio_desc *desc, const char *name,
 	chip = gpiod_to_chip(desc);
 	hwnum = gpio_chip_hwgpio(desc);
 
-	local_desc = gpiochip_request_own_desc(chip, hwnum, name);
+	/*
+	 * FIXME: not very elegant that we call gpiod_configure_flags()
+	 * twice here (once inside gpiochip_request_own_desc() and
+	 * again here), but the gpiochip_request_own_desc() is external
+	 * and cannot really pass the lflags so this is the lesser evil
+	 * at the moment. Pass zero as dflags on this first call so we
+	 * don't screw anything up.
+	 */
+	local_desc = gpiochip_request_own_desc(chip, hwnum, name, 0);
 	if (IS_ERR(local_desc)) {
 		status = PTR_ERR(local_desc);
 		pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",

drivers/hid/hid-cp2112.c

@@ -1203,7 +1203,7 @@ static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
 		return -EINVAL;
 
 	dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
-						   "HID/I2C:Event");
+						   "HID/I2C:Event", 0);
 	if (IS_ERR(dev->desc[pin])) {
 		dev_err(dev->gc.parent, "Failed to request GPIO\n");
 		return PTR_ERR(dev->desc[pin]);

drivers/memory/omap-gpmc.c

@@ -2170,7 +2170,8 @@ static int gpmc_probe_generic_child(struct platform_device *pdev,
 		unsigned int wait_pin = gpmc_s.wait_pin;
 
 		waitpin_desc = gpiochip_request_own_desc(&gpmc->gpio_chip,
-							 wait_pin, "WAITPIN");
+							 wait_pin, "WAITPIN",
+							 0);
 		if (IS_ERR(waitpin_desc)) {
 			dev_err(&pdev->dev, "invalid wait-pin: %d\n", wait_pin);
 			ret = PTR_ERR(waitpin_desc);

include/linux/gpio/driver.h

@@ -17,6 +17,7 @@ struct device_node;
 struct seq_file;
 struct gpio_device;
 struct module;
+enum gpiod_flags;
 
 #ifdef CONFIG_GPIOLIB
 
@@ -604,7 +605,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *chip)
 #endif /* CONFIG_PINCTRL */
 
 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
-					    const char *label);
+					    const char *label,
+					    enum gpiod_flags flags);
 void gpiochip_free_own_desc(struct gpio_desc *desc);
 
 #else /* CONFIG_GPIOLIB */