From baca3b15cd2a171fa967223e2d7aea6e5f98ba9e Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Wed, 11 Nov 2020 20:49:30 +0200
Subject: [PATCH] gpiolib: Extract gpio_set_config_with_argument_optional() helper
Git-commit: baca3b15cd2a171fa967223e2d7aea6e5f98ba9e
Patch-mainline: v5.11-rc1
References: bsc#1180682

[ backport note: yet another modified patch; the new function
  gpio_set_config_with_argument_optional() is prepared here and only the
  code in gpiod_set_transitory() uses this function right now -- tiwai ]
  
This function is useful for internal use in the GPIO library.
There will be new user coming, prepare a helper for the new comer
and the existing ones.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpio/gpiolib.c |   46 ++++++++++++++++++++++++++--------------------
 1 file changed, 26 insertions(+), 20 deletions(-)

--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -2987,6 +2987,29 @@ static int gpio_set_config_with_argument
 	return gpio_do_set_config(gc, gpio_chip_hwgpio(desc), config);
 }
 
+static int gpio_set_config_with_argument_optional(struct gpio_desc *desc,
+						  enum pin_config_param mode,
+						  u32 argument)
+{
+	struct device *dev = &desc->gdev->dev;
+	int gpio = gpio_chip_hwgpio(desc);
+	int ret;
+
+	ret = gpio_set_config_with_argument(desc, mode, argument);
+	if (ret != -ENOTSUPP)
+		return ret;
+
+	switch (mode) {
+	case PIN_CONFIG_PERSIST_STATE:
+		dev_dbg(dev, "Persistence not supported for GPIO %d\n", gpio);
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
 static int gpio_set_config(struct gpio_chip *gc, unsigned int offset,
 			   enum pin_config_param mode)
 {
@@ -3237,11 +3260,6 @@ EXPORT_SYMBOL_GPL(gpiod_set_debounce);
  */
 int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
 {
-	struct gpio_chip *chip;
-	unsigned long packed;
-	int gpio;
-	int rc;
-
 	VALIDATE_DESC(desc);
 	/*
 	 * Handle FLAG_TRANSITORY first, enabling queries to gpiolib for
@@ -3253,21 +3271,9 @@ int gpiod_set_transitory(struct gpio_des
 		clear_bit(FLAG_TRANSITORY, &desc->flags);
 
 	/* If the driver supports it, set the persistence state now */
-	chip = desc->gdev->chip;
-	if (!chip->set_config)
-		return 0;
-
-	packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
-					  !transitory);
-	gpio = gpio_chip_hwgpio(desc);
-	rc = gpio_do_set_config(chip, gpio, packed);
-	if (rc == -ENOTSUPP) {
-		dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
-				gpio);
-		return 0;
-	}
-
-	return rc;
+	return gpio_set_config_with_argument_optional(desc,
+						      PIN_CONFIG_PERSIST_STATE,
+						      !transitory);
 }
 EXPORT_SYMBOL_GPL(gpiod_set_transitory);