lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

of/gpio: stop using device_node data pointer to find gpio_chip

Browse Source 
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 <grant.likely@secretlab.ca>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Anton Vorontsov <avorontsov@ru.mvista.com>
CC: Grant Likely <grant.likely@secretlab.ca>
CC: David Brownell <dbrownell@users.sourceforge.net>
CC: Bill Gatliff <bgat@billgatliff.com>
CC: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Jean Delvare <khali@linux-fr.org>
CC: linux-kernel@vger.kernel.org
CC: devicetree-discuss@lists.ozlabs.org
This commit is contained in:
Grant Likely
2010-06-08 07:48:16 -06:00
parent a19e3da5bc
commit 594fa265e0
8 changed files with 56 additions and 25 deletions
Download Patch File Download Diff File Expand all files Collapse all files

23
arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
View File

@ -35,7 +35,6 @@
struct mcu {
struct mutex lock;
struct device_node *np;
struct i2c_client *client;
struct gpio_chip gc;
u8 reg_ctrl;
@ -79,7 +78,6 @@ static int mcu_gpiochip_add(struct mcu *mcu)
{
struct device_node *np;
struct gpio_chip *gc = &mcu->gc;
int ret;
np = of_find_compatible_node(NULL, NULL, "fsl,mcu-mpc8349emitx");
if (!np)
@ -94,29 +92,14 @@ static int mcu_gpiochip_add(struct mcu *mcu)
gc->direction_output = mcu_gpio_dir_out;
gc->of_gpio_n_cells = 2;
gc->of_xlate = of_gpio_simple_xlate;
gc->of_node = np;
mcu->np = np;
/*
* We don't want to lose the node, its ->data and ->full_name...
* So, if succeeded, we don't put the node here.
*/
ret = gpiochip_add(gc);
if (ret)
of_node_put(np);
return ret;
return gpiochip_add(gc);
}
static int mcu_gpiochip_remove(struct mcu *mcu)
{
int ret;
ret = gpiochip_remove(&mcu->gc);
if (ret)
return ret;
of_node_put(mcu->np);
return 0;
return gpiochip_remove(&mcu->gc);
}
static int __devinit mcu_probe(struct i2c_client *client,