of/gpio: Kill of_gpio_chip and add members directly to gpio_chip

The OF gpio infrastructure is great for describing GPIO connections within
the device tree.  However, using a GPIO binding still requires changes to
the gpio controller just to add an of_gpio structure.  In most cases, the
gpio controller doesn't actually need any special support and the simple
OF gpio mapping function is more than sufficient.  Additional, the current
scheme of using of_gpio_chip requires a convoluted scheme to maintain
1:1 mappings between of_gpio_chip and gpio_chip instances.

If the struct of_gpio_chip data members were moved into struct gpio_chip,
then it would simplify the processing of OF gpio bindings, and it would
make it trivial to use device tree OF connections on existing gpiolib
controller drivers.

This patch eliminates the of_gpio_chip structure and moves the relevant
fields into struct gpio_chip (conditional on CONFIG_OF_GPIO).  This move
simplifies the existing code and prepares for adding automatic device tree
support to existing drivers.

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>

1 files changed, 14 insertions, 15 deletions

diff --git a/arch/powerpc/platforms/52xx/mpc52xx_gpt.c b/arch/powerpc/platforms/52xx/mpc52xx_gpt.c
index 46c93578cbf0..3f2ee47f1d01 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_gpt.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_gpt.c
@@ -78,7 +78,7 @@ MODULE_LICENSE("GPL");
  * @dev: pointer to device structure
  * @regs: virtual address of GPT registers
  * @lock: spinlock to coordinate between different functions.
- * @of_gc: of_gpio_chip instance structure; used when GPIO is enabled
+ * @gc: gpio_chip instance structure; used when GPIO is enabled
  * @irqhost: Pointer to irq_host instance; used when IRQ mode is supported
  * @wdt_mode: only relevant for gpt0: bit 0 (MPC52xx_GPT_CAN_WDT) indicates
  *   if the gpt may be used as wdt, bit 1 (MPC52xx_GPT_IS_WDT) indicates
@@ -94,7 +94,7 @@ struct mpc52xx_gpt_priv {
 	u8 wdt_mode;
 
 #if defined(CONFIG_GPIOLIB)
-	struct of_gpio_chip of_gc;
+	struct gpio_chip gc;
 #endif
 };
 
@@ -280,7 +280,7 @@ mpc52xx_gpt_irq_setup(struct mpc52xx_gpt_priv *gpt, struct device_node *node)
 #if defined(CONFIG_GPIOLIB)
 static inline struct mpc52xx_gpt_priv *gc_to_mpc52xx_gpt(struct gpio_chip *gc)
 {
-	return container_of(to_of_gpio_chip(gc), struct mpc52xx_gpt_priv,of_gc);
+	return container_of(gc, struct mpc52xx_gpt_priv, gc);
 }
 
 static int mpc52xx_gpt_gpio_get(struct gpio_chip *gc, unsigned int gpio)
@@ -336,28 +336,27 @@ mpc52xx_gpt_gpio_setup(struct mpc52xx_gpt_priv *gpt, struct device_node *node)
 	if (!of_find_property(node, "gpio-controller", NULL))
 		return;
 
-	gpt->of_gc.gc.label = kstrdup(node->full_name, GFP_KERNEL);
-	if (!gpt->of_gc.gc.label) {
+	gpt->gc.label = kstrdup(node->full_name, GFP_KERNEL);
+	if (!gpt->gc.label) {
 		dev_err(gpt->dev, "out of memory\n");
 		return;
 	}
 
-	gpt->of_gc.gpio_cells = 2;
-	gpt->of_gc.gc.ngpio = 1;
-	gpt->of_gc.gc.direction_input  = mpc52xx_gpt_gpio_dir_in;
-	gpt->of_gc.gc.direction_output = mpc52xx_gpt_gpio_dir_out;
-	gpt->of_gc.gc.get = mpc52xx_gpt_gpio_get;
-	gpt->of_gc.gc.set = mpc52xx_gpt_gpio_set;
-	gpt->of_gc.gc.base = -1;
-	gpt->of_gc.xlate = of_gpio_simple_xlate;
-	node->data = &gpt->of_gc;
+	gpt->gc.ngpio = 1;
+	gpt->gc.direction_input  = mpc52xx_gpt_gpio_dir_in;
+	gpt->gc.direction_output = mpc52xx_gpt_gpio_dir_out;
+	gpt->gc.get = mpc52xx_gpt_gpio_get;
+	gpt->gc.set = mpc52xx_gpt_gpio_set;
+	gpt->gc.base = -1;
+	gpt->gc.of_gpio_n_cells = 2;
+	gpt->gc.of_xlate = of_gpio_simple_xlate;
 	of_node_get(node);
 
 	/* Setup external pin in GPIO mode */
 	clrsetbits_be32(&gpt->regs->mode, MPC52xx_GPT_MODE_MS_MASK,
 			MPC52xx_GPT_MODE_MS_GPIO);
 
-	rc = gpiochip_add(&gpt->of_gc.gc);
+	rc = gpiochip_add(&gpt->gc);
 	if (rc)
 		dev_err(gpt->dev, "gpiochip_add() failed; rc=%i\n", rc);