linux-kernel - [PATCH 5.4 048/102] gpiolib: No need to call gpiochip_remove_pin

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Date:   Fri, 24 Jan 2020 10:30:49 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org,
        Geert Uytterhoeven <geert+renesas@...der.be>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Linus Walleij <linus.walleij@...aro.org>
Subject: [PATCH 5.4 048/102] gpiolib: No need to call gpiochip_remove_pin_ranges() twice

From: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>

commit 2f4133bb5f14f49a99acf0cc55b84996dbfb4dff upstream.

of_gpiochip_add(), when fails, calls gpiochip_remove_pin_ranges().

ADD:
  gpiochip_add_data_with_key() ->
    of_gpiochip_add() -> (ERROR path)
      gpiochip_remove_pin_ranges()

At the same time of_gpiochip_remove() calls exactly the above mentioned
function unconditionally and so does gpiochip_remove().

REMOVE:
  gpiochip_remove() ->
    gpiochip_remove_pin_ranges()
    of_gpiochip_remove() ->
      gpiochip_remove_pin_ranges()

Since gpiochip_remove() calls gpiochip_remove_pin_ranges() unconditionally,
we have duplicate call to the same function when it's not necessary.

Move gpiochip_remove_pin_ranges() from of_gpiochip_add() to gpiochip_add()
to avoid duplicate calls and be consistent with the explicit call in
gpiochip_remove().

Fixes: e93fa3f24353 ("gpiolib: remove duplicate pin range code")
Depends-on: f7299d441a4d ("gpio: of: Fix of_gpiochip_add() error path")
Cc: Geert Uytterhoeven <geert+renesas@...der.be>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@...aro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/gpio/gpiolib-of.c |    5 +----
 drivers/gpio/gpiolib.c    |    3 ++-
 2 files changed, 3 insertions(+), 5 deletions(-)

--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -909,16 +909,13 @@ int of_gpiochip_add(struct gpio_chip *ch
 	of_node_get(chip->of_node);
 
 	ret = of_gpiochip_scan_gpios(chip);
-	if (ret) {
+	if (ret)
 		of_node_put(chip->of_node);
-		gpiochip_remove_pin_ranges(chip);
-	}
 
 	return ret;
 }
 
 void of_gpiochip_remove(struct gpio_chip *chip)
 {
-	gpiochip_remove_pin_ranges(chip);
 	of_node_put(chip->of_node);
 }
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1452,6 +1452,7 @@ err_remove_of_chip:
 	gpiochip_free_hogs(chip);
 	of_gpiochip_remove(chip);
 err_free_gpiochip_mask:
+	gpiochip_remove_pin_ranges(chip);
 	gpiochip_free_valid_mask(chip);
 err_remove_from_list:
 	spin_lock_irqsave(&gpio_lock, flags);
@@ -1507,8 +1508,8 @@ void gpiochip_remove(struct gpio_chip *c
 	gdev->chip = NULL;
 	gpiochip_irqchip_remove(chip);
 	acpi_gpiochip_remove(chip);
-	gpiochip_remove_pin_ranges(chip);
 	of_gpiochip_remove(chip);
+	gpiochip_remove_pin_ranges(chip);
 	gpiochip_free_valid_mask(chip);
 	/*
 	 * We accept no more calls into the driver from this point, so