From 594fa265e084073443390c5b93d5410fd28e9bcd Mon Sep 17 00:00:00 2001 From: Grant Likely Date: Tue, 8 Jun 2010 07:48:16 -0600 Subject: of/gpio: stop using device_node data pointer to find gpio_chip Currently the kernel uses the struct device_node.data pointer to resolve a struct gpio_chip pointer from a device tree node. However, the .data member doesn't provide any type checking and there aren't any rules enforced on what it should be used for. There's no guarantee that the data stored in it actually points to an gpio_chip pointer. Instead of relying on the .data pointer, this patch modifies the code to add a lookup function which scans through the registered gpio_chips and returns the gpio_chip that has a pointer to the specified device_node. Signed-off-by: Grant Likely CC: Andrew Morton CC: Anton Vorontsov CC: Grant Likely CC: David Brownell CC: Bill Gatliff CC: Dmitry Eremin-Solenikov CC: Benjamin Herrenschmidt CC: Jean Delvare CC: linux-kernel@vger.kernel.org CC: devicetree-discuss@lists.ozlabs.org --- drivers/of/gpio.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'drivers/of') diff --git a/drivers/of/gpio.c b/drivers/of/gpio.c index fde53a3a45a3..c8618d3282cf 100644 --- a/drivers/of/gpio.c +++ b/drivers/of/gpio.c @@ -46,7 +46,7 @@ int of_get_gpio_flags(struct device_node *np, int index, goto err0; } - gc = gpio_np->data; + gc = of_node_to_gpiochip(gpio_np); if (!gc) { pr_debug("%s: gpio controller %s isn't registered\n", np->full_name, gpio_np->full_name); @@ -193,7 +193,6 @@ int of_mm_gpiochip_add(struct device_node *np, if (mm_gc->save_regs) mm_gc->save_regs(mm_gc); - np->data = &mm_gc->gc; mm_gc->gc.of_node = np; ret = gpiochip_add(gc); @@ -207,7 +206,6 @@ int of_mm_gpiochip_add(struct device_node *np, np->full_name, gc->base); return 0; err2: - np->data = NULL; iounmap(mm_gc->regs); err1: kfree(gc->label); @@ -217,3 +215,14 @@ err0: return ret; } EXPORT_SYMBOL(of_mm_gpiochip_add); + +/* Private function for resolving node pointer to gpio_chip */ +static int of_gpiochip_is_match(struct gpio_chip *chip, void *data) +{ + return chip->of_node == data; +} + +struct gpio_chip *of_node_to_gpiochip(struct device_node *np) +{ + return gpiochip_find(np, of_gpiochip_is_match); +} -- cgit v1.2.3