[PATCH] gpio: pass lookup and descriptor flags to request_own

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

When a gpio_chip wants to request a descriptor from itself
using gpiochip_request_own_desc() it needs to be able to specify
fully how to use the descriptor, notably line inversion
semantics. The workaround in the gpiolib.c can be removed
and cases (such as SPI CS) where we need at times to request
a GPIO with line inversion semantics directly on a chip for
workarounds, can be fully supported with this call.

Cc: Martin Sperl <kernel@xxxxxxxxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
Hi Martin, I plan to merge this to make a proper solution
for BCM2835 CS GPIO descriptors in the next kernel cycle.
---
 arch/arm/mach-omap1/ams-delta-fiq.c   |  2 +-
 arch/arm/mach-omap1/board-ams-delta.c |  2 +-
 drivers/gpio/gpio-mvebu.c             |  2 +-
 drivers/gpio/gpiolib-acpi.c           |  4 ++--
 drivers/gpio/gpiolib.c                | 30 +++++++++------------------
 drivers/hid/hid-cp2112.c              |  2 +-
 drivers/memory/omap-gpmc.c            |  2 +-
 include/linux/gpio/driver.h           |  4 +++-
 8 files changed, 20 insertions(+), 28 deletions(-)

diff --git a/arch/arm/mach-omap1/ams-delta-fiq.c b/arch/arm/mach-omap1/ams-delta-fiq.c
index 51212133ce06..1242bf551c1c 100644
--- a/arch/arm/mach-omap1/ams-delta-fiq.c
+++ b/arch/arm/mach-omap1/ams-delta-fiq.c
@@ -102,7 +102,7 @@ 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], 0);
+		gpiod = gpiochip_request_own_desc(chip, i, pin_name[i], 0, 0);
 		if (IS_ERR(gpiod)) {
 			pr_err("%s: failed to get GPIO pin %d (%ld)\n",
 			       __func__, i, PTR_ERR(gpiod));
diff --git a/arch/arm/mach-omap1/board-ams-delta.c b/arch/arm/mach-omap1/board-ams-delta.c
index be30c3c061b4..89ca58a41440 100644
--- a/arch/arm/mach-omap1/board-ams-delta.c
+++ b/arch/arm/mach-omap1/board-ams-delta.c
@@ -607,7 +607,7 @@ static void __init modem_assign_irq(struct gpio_chip *chip)
 	struct gpio_desc *gpiod;
 
 	gpiod = gpiochip_request_own_desc(chip, AMS_DELTA_GPIO_PIN_MODEM_IRQ,
-					  "modem_irq", 0);
+					  "modem_irq", 0, 0);
 	if (IS_ERR(gpiod)) {
 		pr_err("%s: modem IRQ GPIO request failed (%ld)\n", __func__,
 		       PTR_ERR(gpiod));
diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c
index f97ed32b8beb..fa333218dec2 100644
--- a/drivers/gpio/gpio-mvebu.c
+++ b/drivers/gpio/gpio-mvebu.c
@@ -618,7 +618,7 @@ 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", 0);
+						 pwm->hwpwm, "mvebu-pwm", 0, 0);
 		if (IS_ERR(desc)) {
 			ret = PTR_ERR(desc);
 			goto out;
diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
index 30d0baf7ddae..c827b0d26f1e 100644
--- a/drivers/gpio/gpiolib-acpi.c
+++ b/drivers/gpio/gpiolib-acpi.c
@@ -217,7 +217,7 @@ static acpi_status acpi_gpiochip_alloc_event(struct acpi_resource *ares,
 	if (!handler)
 		return AE_OK;
 
-	desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event", 0);
+	desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event", 0, 0);
 	if (IS_ERR(desc)) {
 		dev_err(chip->parent, "Failed to request GPIO\n");
 		return AE_ERROR;
@@ -920,7 +920,7 @@ acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
 			const char *label = "ACPI:OpRegion";
 
 			desc = gpiochip_request_own_desc(chip, pin, label,
-							 flags);
+							 0, flags);
 			if (IS_ERR(desc)) {
 				status = AE_ERROR;
 				mutex_unlock(&achip->conn_lock);
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 144af0733581..d00642ba931e 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2499,7 +2499,11 @@ 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
+ * @lflags: lookup flags for this GPIO or 0 if default, this can be used to
+ * specify things like line inversion semantics with the machine flags
+ * such as GPIO_OUT_LOW
+ * @dflags: descriptor request flags for this GPIO or 0 if default, this
+ * can be used to specify consumer semantics such as open drain
  *
  * Function allows GPIO chip drivers to request and use their own GPIO
  * descriptors via gpiolib API. Difference to gpiod_request() is that this
@@ -2513,7 +2517,8 @@ EXPORT_SYMBOL_GPL(gpiochip_is_requested);
  */
 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
 					    const char *label,
-					    enum gpiod_flags flags)
+					    enum gpio_lookup_flags lflags,
+					    enum gpiod_flags dflags)
 {
 	struct gpio_desc *desc = gpiochip_get_desc(chip, hwnum);
 	int err;
@@ -2527,7 +2532,7 @@ 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);
+	err = gpiod_configure_flags(desc, label, lflags, dflags);
 	if (err) {
 		chip_err(chip, "setup of own GPIO %s failed\n", label);
 		gpiod_free_commit(desc);
@@ -4406,15 +4411,8 @@ int gpiod_hog(struct gpio_desc *desc, const char *name,
 	chip = gpiod_to_chip(desc);
 	hwnum = gpio_chip_hwgpio(desc);
 
-	/*
-	 * 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);
+	local_desc = gpiochip_request_own_desc(chip, hwnum, name,
+					       lflags, dflags);
 	if (IS_ERR(local_desc)) {
 		status = PTR_ERR(local_desc);
 		pr_err("requesting hog GPIO %s (chip %s, offset %d) failed, %d\n",
@@ -4422,14 +4420,6 @@ int gpiod_hog(struct gpio_desc *desc, const char *name,
 		return status;
 	}
 
-	status = gpiod_configure_flags(desc, name, lflags, dflags);
-	if (status < 0) {
-		pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
-		       name, chip->label, hwnum, status);
-		gpiochip_free_own_desc(desc);
-		return status;
-	}
-
 	/* Mark GPIO as hogged so it can be identified and removed later */
 	set_bit(FLAG_IS_HOGGED, &desc->flags);
 
diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c
index 47f65857408d..90ee0cf2c14d 100644
--- a/drivers/hid/hid-cp2112.c
+++ b/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", 0);
+						   "HID/I2C:Event", 0, 0);
 	if (IS_ERR(dev->desc[pin])) {
 		dev_err(dev->gc.parent, "Failed to request GPIO\n");
 		return PTR_ERR(dev->desc[pin]);
diff --git a/drivers/memory/omap-gpmc.c b/drivers/memory/omap-gpmc.c
index f6297599433f..05ad63928daf 100644
--- a/drivers/memory/omap-gpmc.c
+++ b/drivers/memory/omap-gpmc.c
@@ -2172,7 +2172,7 @@ static int gpmc_probe_generic_child(struct platform_device *pdev,
 
 		waitpin_desc = gpiochip_request_own_desc(&gpmc->gpio_chip,
 							 wait_pin, "WAITPIN",
-							 0);
+							 0, 0);
 		if (IS_ERR(waitpin_desc)) {
 			dev_err(&pdev->dev, "invalid wait-pin: %d\n", wait_pin);
 			ret = PTR_ERR(waitpin_desc);
diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 01497910f023..2d422386799e 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -18,6 +18,7 @@ struct seq_file;
 struct gpio_device;
 struct module;
 enum gpiod_flags;
+enum gpio_lookup_flags;
 
 #ifdef CONFIG_GPIOLIB
 
@@ -611,7 +612,8 @@ gpiochip_remove_pin_ranges(struct gpio_chip *chip)
 
 struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *chip, u16 hwnum,
 					    const char *label,
-					    enum gpiod_flags flags);
+					    enum gpio_lookup_flags lflags,
+					    enum gpiod_flags dflags);
 void gpiochip_free_own_desc(struct gpio_desc *desc);
 
 #else /* CONFIG_GPIOLIB */
-- 
2.20.1