of/gpio: add default of_xlate function if device has a node pointer

Implement generic OF gpio hooks and thus make device-enabled GPIO chips
(i.e.  the ones that have gpio_chip->dev specified) automatically attach
to the OpenFirmware subsystem.  Which means that now we can handle I2C and
SPI GPIO chips almost* transparently.

* "Almost" because some chips still require platform data, and for these
  chips OF-glue is still needed, though with this change the glue will
  be much smaller.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: 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: Andrew Morton <akpm@linux-foundation.org>
CC: linux-kernel@vger.kernel.org
CC: devicetree-discuss@lists.ozlabs.org

2 files changed, 5 insertions, 1 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 73fd328f6fe4..83cbc34e3a76 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -8,6 +8,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/gpio.h>
+#include <linux/of_gpio.h>
 #include <linux/idr.h>
 #include <linux/slab.h>
 
@@ -1099,6 +1100,8 @@ int gpiochip_add(struct gpio_chip *chip)
                 }
         }
 
+        of_gpiochip_add(chip);
+
 unlock:
         spin_unlock_irqrestore(&gpio_lock, flags);
 
@@ -1133,6 +1136,8 @@ int gpiochip_remove(struct gpio_chip *chip)
 
         spin_lock_irqsave(&gpio_lock, flags);
 
+        of_gpiochip_remove(chip);
+
         for (id = chip->base; id < chip->base + chip->ngpio; id++) {
                 if (test_bit(FLAG_REQUESTED, &gpio_desc[id].flags)) {
                         status = -EBUSY;
diff --git a/drivers/gpio/xilinx_gpio.c b/drivers/gpio/xilinx_gpio.c
index 2993c40b48e1..709690995d0d 100644
--- a/drivers/gpio/xilinx_gpio.c
+++ b/drivers/gpio/xilinx_gpio.c
@@ -190,7 +190,6 @@ static int __devinit xgpio_of_probe(struct device_node *np)
 
         spin_lock_init(&chip->gpio_lock);
 
-        chip->mmchip.gc.of_gpio_n_cells = 2;
         chip->mmchip.gc.direction_input = xgpio_dir_in;
         chip->mmchip.gc.direction_output = xgpio_dir_out;
         chip->mmchip.gc.get = xgpio_get;