Commit 6ff04974 authored Aug 06, 2018 by Biju Das Committed by Linus Walleij Aug 10, 2018

gpiolib: Fix of_node inconsistency



Some platforms are not setting of_node in the driver. On these platforms
defining gpio-reserved-ranges on device tree leads to kernel crash.

It is due to some parts of the gpio core relying on the driver to set up
of_node,while other parts do themselves.This inconsistent behaviour leads
to a crash.

gpiochip_add_data_with_key() calls gpiochip_init_valid_mask() with of_node
as NULL. of_gpiochip_add() fills "of_node" and calls
of_gpiochip_init_valid_mask().

The fix is to move the assignment to chip->of_node from of_gpiochip_add()
to gpiochip_add_data_with_key().

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

parent f8ad8aa5

drivers/gpio/gpiolib-of.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -620,9 +620,6 @@ int of_gpiochip_add(struct gpio_chip *chip)
		{
		int status;

		if ((!chip->of_node) && (chip->parent))
		chip->of_node = chip->parent->of_node;

		if (!chip->of_node)
		return 0;

drivers/gpio/gpiolib.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -1262,6 +1262,8 @@ int gpiochip_add_data_with_key(struct gpio_chip chip, void data,
		/* If the gpiochip has an assigned OF node this takes precedence */
		if (chip->of_node)
		gdev->dev.of_node = chip->of_node;
		else
		chip->of_node = gdev->dev.of_node;
		#endif

		gdev->id = ida_simple_get(&gpio_ida, 0, 0, GFP_KERNEL);

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