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>
diff --git a/arch/microblaze/kernel/reset.c b/arch/microblaze/kernel/reset.c
index a1721a3..5476d3c 100644
--- a/arch/microblaze/kernel/reset.c
+++ b/arch/microblaze/kernel/reset.c
@@ -24,8 +24,8 @@
 	int ret; /* variable which stored handle reset gpio pin */
 	struct device_node *root; /* root node */
 	struct device_node *gpio; /* gpio node */
-	struct of_gpio_chip *of_gc = NULL;
-	enum of_gpio_flags flags ;
+	struct gpio_chip *gc;
+	u32 flags;
 	const void *gpio_spec;
 
 	/* find out root node */
@@ -39,19 +39,19 @@
 		goto err0;
 	}
 
-	of_gc = gpio->data;
-	if (!of_gc) {
+	gc = gpio->data;
+	if (!gc) {
 		pr_debug("%s: gpio controller %s isn't registered\n",
 			 root->full_name, gpio->full_name);
 		ret = -ENODEV;
 		goto err1;
 	}
 
-	ret = of_gc->xlate(of_gc, root, gpio_spec, &flags);
+	ret = gc->of_xlate(gc, root, gpio_spec, &flags);
 	if (ret < 0)
 		goto err1;
 
-	ret += of_gc->gc.base;
+	ret += gc->base;
 err1:
 	of_node_put(gpio);
 err0:
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_gpio.c b/arch/powerpc/platforms/52xx/mpc52xx_gpio.c
index ca5305a..fd0912e 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_gpio.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_gpio.c
@@ -152,21 +152,21 @@
 {
 	struct mpc52xx_gpiochip *chip;
 	struct mpc52xx_gpio_wkup __iomem *regs;
-	struct of_gpio_chip *ofchip;
+	struct gpio_chip *gc;
 	int ret;
 
 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;
 
-	ofchip = &chip->mmchip.of_gc;
+	gc = &chip->mmchip.gc;
 
-	ofchip->gpio_cells          = 2;
-	ofchip->gc.ngpio            = 8;
-	ofchip->gc.direction_input  = mpc52xx_wkup_gpio_dir_in;
-	ofchip->gc.direction_output = mpc52xx_wkup_gpio_dir_out;
-	ofchip->gc.get              = mpc52xx_wkup_gpio_get;
-	ofchip->gc.set              = mpc52xx_wkup_gpio_set;
+	gc->of_gpio_n_cells  = 2;
+	gc->ngpio            = 8;
+	gc->direction_input  = mpc52xx_wkup_gpio_dir_in;
+	gc->direction_output = mpc52xx_wkup_gpio_dir_out;
+	gc->get              = mpc52xx_wkup_gpio_get;
+	gc->set              = mpc52xx_wkup_gpio_set;
 
 	ret = of_mm_gpiochip_add(ofdev->dev.of_node, &chip->mmchip);
 	if (ret)
@@ -315,7 +315,7 @@
 					const struct of_device_id *match)
 {
 	struct mpc52xx_gpiochip *chip;
-	struct of_gpio_chip *ofchip;
+	struct gpio_chip *gc;
 	struct mpc52xx_gpio __iomem *regs;
 	int ret;
 
@@ -323,14 +323,14 @@
 	if (!chip)
 		return -ENOMEM;
 
-	ofchip = &chip->mmchip.of_gc;
+	gc = &chip->mmchip.gc;
 
-	ofchip->gpio_cells          = 2;
-	ofchip->gc.ngpio            = 32;
-	ofchip->gc.direction_input  = mpc52xx_simple_gpio_dir_in;
-	ofchip->gc.direction_output = mpc52xx_simple_gpio_dir_out;
-	ofchip->gc.get              = mpc52xx_simple_gpio_get;
-	ofchip->gc.set              = mpc52xx_simple_gpio_set;
+	gc->of_gpio_n_cells  = 2;
+	gc->ngpio            = 32;
+	gc->direction_input  = mpc52xx_simple_gpio_dir_in;
+	gc->direction_output = mpc52xx_simple_gpio_dir_out;
+	gc->get              = mpc52xx_simple_gpio_get;
+	gc->set              = mpc52xx_simple_gpio_set;
 
 	ret = of_mm_gpiochip_add(ofdev->dev.of_node, &chip->mmchip);
 	if (ret)
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_gpt.c b/arch/powerpc/platforms/52xx/mpc52xx_gpt.c
index 46c9357..3f2ee47 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_gpt.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_gpt.c
@@ -78,7 +78,7 @@
  * @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 @@
 	u8 wdt_mode;
 
 #if defined(CONFIG_GPIOLIB)
-	struct of_gpio_chip of_gc;
+	struct gpio_chip gc;
 #endif
 };
 
@@ -280,7 +280,7 @@
 #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 @@
 	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);
 
diff --git a/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c b/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
index d119a7c..e49f4bd 100644
--- a/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
+++ b/arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c
@@ -37,7 +37,7 @@
 	struct mutex lock;
 	struct device_node *np;
 	struct i2c_client *client;
-	struct of_gpio_chip of_gc;
+	struct gpio_chip gc;
 	u8 reg_ctrl;
 };
 
@@ -56,8 +56,7 @@
 
 static void mcu_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
 {
-	struct of_gpio_chip *of_gc = to_of_gpio_chip(gc);
-	struct mcu *mcu = container_of(of_gc, struct mcu, of_gc);
+	struct mcu *mcu = container_of(gc, struct mcu, gc);
 	u8 bit = 1 << (4 + gpio);
 
 	mutex_lock(&mcu->lock);
@@ -79,8 +78,7 @@
 static int mcu_gpiochip_add(struct mcu *mcu)
 {
 	struct device_node *np;
-	struct of_gpio_chip *of_gc = &mcu->of_gc;
-	struct gpio_chip *gc = &of_gc->gc;
+	struct gpio_chip *gc = &mcu->gc;
 	int ret;
 
 	np = of_find_compatible_node(NULL, NULL, "fsl,mcu-mpc8349emitx");
@@ -94,10 +92,9 @@
 	gc->base = -1;
 	gc->set = mcu_gpio_set;
 	gc->direction_output = mcu_gpio_dir_out;
-	of_gc->gpio_cells = 2;
-	of_gc->xlate = of_gpio_simple_xlate;
+	gc->of_gpio_n_cells = 2;
+	gc->of_xlate = of_gpio_simple_xlate;
 
-	np->data = of_gc;
 	mcu->np = np;
 
 	/*
@@ -114,7 +111,7 @@
 {
 	int ret;
 
-	ret = gpiochip_remove(&mcu->of_gc.gc);
+	ret = gpiochip_remove(&mcu->gc);
 	if (ret)
 		return ret;
 	of_node_put(mcu->np);
diff --git a/arch/powerpc/platforms/86xx/gef_gpio.c b/arch/powerpc/platforms/86xx/gef_gpio.c
index b8cb08d..4ff7b1e 100644
--- a/arch/powerpc/platforms/86xx/gef_gpio.c
+++ b/arch/powerpc/platforms/86xx/gef_gpio.c
@@ -118,12 +118,12 @@
 		}
 
 		/* Setup pointers to chip functions */
-		gef_gpio_chip->of_gc.gpio_cells = 2;
-		gef_gpio_chip->of_gc.gc.ngpio = 19;
-		gef_gpio_chip->of_gc.gc.direction_input = gef_gpio_dir_in;
-		gef_gpio_chip->of_gc.gc.direction_output = gef_gpio_dir_out;
-		gef_gpio_chip->of_gc.gc.get = gef_gpio_get;
-		gef_gpio_chip->of_gc.gc.set = gef_gpio_set;
+		gef_gpio_chip->gc.of_gpio_n_cells = 2;
+		gef_gpio_chip->gc.ngpio = 19;
+		gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
+		gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
+		gef_gpio_chip->gc.get = gef_gpio_get;
+		gef_gpio_chip->gc.set = gef_gpio_set;
 
 		/* This function adds a memory mapped GPIO chip */
 		retval = of_mm_gpiochip_add(np, gef_gpio_chip);
@@ -146,12 +146,12 @@
 		}
 
 		/* Setup pointers to chip functions */
-		gef_gpio_chip->of_gc.gpio_cells = 2;
-		gef_gpio_chip->of_gc.gc.ngpio = 6;
-		gef_gpio_chip->of_gc.gc.direction_input = gef_gpio_dir_in;
-		gef_gpio_chip->of_gc.gc.direction_output = gef_gpio_dir_out;
-		gef_gpio_chip->of_gc.gc.get = gef_gpio_get;
-		gef_gpio_chip->of_gc.gc.set = gef_gpio_set;
+		gef_gpio_chip->gc.of_gpio_n_cells = 2;
+		gef_gpio_chip->gc.ngpio = 6;
+		gef_gpio_chip->gc.direction_input = gef_gpio_dir_in;
+		gef_gpio_chip->gc.direction_output = gef_gpio_dir_out;
+		gef_gpio_chip->gc.get = gef_gpio_get;
+		gef_gpio_chip->gc.set = gef_gpio_set;
 
 		/* This function adds a memory mapped GPIO chip */
 		retval = of_mm_gpiochip_add(np, gef_gpio_chip);
diff --git a/arch/powerpc/sysdev/cpm1.c b/arch/powerpc/sysdev/cpm1.c
index 8d103ca..d5cf7d4 100644
--- a/arch/powerpc/sysdev/cpm1.c
+++ b/arch/powerpc/sysdev/cpm1.c
@@ -621,7 +621,6 @@
 {
 	struct cpm1_gpio16_chip *cpm1_gc;
 	struct of_mm_gpio_chip *mm_gc;
-	struct of_gpio_chip *of_gc;
 	struct gpio_chip *gc;
 
 	cpm1_gc = kzalloc(sizeof(*cpm1_gc), GFP_KERNEL);
@@ -631,11 +630,10 @@
 	spin_lock_init(&cpm1_gc->lock);
 
 	mm_gc = &cpm1_gc->mm_gc;
-	of_gc = &mm_gc->of_gc;
-	gc = &of_gc->gc;
+	gc = &mm_gc->gc;
 
 	mm_gc->save_regs = cpm1_gpio16_save_regs;
-	of_gc->gpio_cells = 2;
+	gc->of_gpio_n_cells = 2;
 	gc->ngpio = 16;
 	gc->direction_input = cpm1_gpio16_dir_in;
 	gc->direction_output = cpm1_gpio16_dir_out;
@@ -745,7 +743,6 @@
 {
 	struct cpm1_gpio32_chip *cpm1_gc;
 	struct of_mm_gpio_chip *mm_gc;
-	struct of_gpio_chip *of_gc;
 	struct gpio_chip *gc;
 
 	cpm1_gc = kzalloc(sizeof(*cpm1_gc), GFP_KERNEL);
@@ -755,11 +752,10 @@
 	spin_lock_init(&cpm1_gc->lock);
 
 	mm_gc = &cpm1_gc->mm_gc;
-	of_gc = &mm_gc->of_gc;
-	gc = &of_gc->gc;
+	gc = &mm_gc->gc;
 
 	mm_gc->save_regs = cpm1_gpio32_save_regs;
-	of_gc->gpio_cells = 2;
+	gc->of_gpio_n_cells = 2;
 	gc->ngpio = 32;
 	gc->direction_input = cpm1_gpio32_dir_in;
 	gc->direction_output = cpm1_gpio32_dir_out;
diff --git a/arch/powerpc/sysdev/cpm_common.c b/arch/powerpc/sysdev/cpm_common.c
index 88b9812..67e9b47 100644
--- a/arch/powerpc/sysdev/cpm_common.c
+++ b/arch/powerpc/sysdev/cpm_common.c
@@ -325,7 +325,6 @@
 {
 	struct cpm2_gpio32_chip *cpm2_gc;
 	struct of_mm_gpio_chip *mm_gc;
-	struct of_gpio_chip *of_gc;
 	struct gpio_chip *gc;
 
 	cpm2_gc = kzalloc(sizeof(*cpm2_gc), GFP_KERNEL);
@@ -335,11 +334,10 @@
 	spin_lock_init(&cpm2_gc->lock);
 
 	mm_gc = &cpm2_gc->mm_gc;
-	of_gc = &mm_gc->of_gc;
-	gc = &of_gc->gc;
+	gc = &mm_gc->gc;
 
 	mm_gc->save_regs = cpm2_gpio32_save_regs;
-	of_gc->gpio_cells = 2;
+	gc->of_gpio_n_cells = 2;
 	gc->ngpio = 32;
 	gc->direction_input = cpm2_gpio32_dir_in;
 	gc->direction_output = cpm2_gpio32_dir_out;
diff --git a/arch/powerpc/sysdev/mpc8xxx_gpio.c b/arch/powerpc/sysdev/mpc8xxx_gpio.c
index 83f5196..ec8fcd4 100644
--- a/arch/powerpc/sysdev/mpc8xxx_gpio.c
+++ b/arch/powerpc/sysdev/mpc8xxx_gpio.c
@@ -257,7 +257,6 @@
 {
 	struct mpc8xxx_gpio_chip *mpc8xxx_gc;
 	struct of_mm_gpio_chip *mm_gc;
-	struct of_gpio_chip *of_gc;
 	struct gpio_chip *gc;
 	unsigned hwirq;
 	int ret;
@@ -271,11 +270,10 @@
 	spin_lock_init(&mpc8xxx_gc->lock);
 
 	mm_gc = &mpc8xxx_gc->mm_gc;
-	of_gc = &mm_gc->of_gc;
-	gc = &of_gc->gc;
+	gc = &mm_gc->gc;
 
 	mm_gc->save_regs = mpc8xxx_gpio_save_regs;
-	of_gc->gpio_cells = 2;
+	gc->of_gpio_n_cells = 2;
 	gc->ngpio = MPC8XXX_GPIO_PINS;
 	gc->direction_input = mpc8xxx_gpio_dir_in;
 	gc->direction_output = mpc8xxx_gpio_dir_out;
diff --git a/arch/powerpc/sysdev/ppc4xx_gpio.c b/arch/powerpc/sysdev/ppc4xx_gpio.c
index 3812fc3..42e7a5e 100644
--- a/arch/powerpc/sysdev/ppc4xx_gpio.c
+++ b/arch/powerpc/sysdev/ppc4xx_gpio.c
@@ -181,7 +181,6 @@
 		int ret;
 		struct ppc4xx_gpio_chip *ppc4xx_gc;
 		struct of_mm_gpio_chip *mm_gc;
-		struct of_gpio_chip *of_gc;
 		struct gpio_chip *gc;
 
 		ppc4xx_gc = kzalloc(sizeof(*ppc4xx_gc), GFP_KERNEL);
@@ -193,10 +192,9 @@
 		spin_lock_init(&ppc4xx_gc->lock);
 
 		mm_gc = &ppc4xx_gc->mm_gc;
-		of_gc = &mm_gc->of_gc;
-		gc = &of_gc->gc;
+		gc = &mm_gc->gc;
 
-		of_gc->gpio_cells = 2;
+		gc->of_gpio_n_cells = 2;
 		gc->ngpio = 32;
 		gc->direction_input = ppc4xx_gpio_dir_in;
 		gc->direction_output = ppc4xx_gpio_dir_out;
diff --git a/arch/powerpc/sysdev/qe_lib/gpio.c b/arch/powerpc/sysdev/qe_lib/gpio.c
index dc8f8d6..194478c 100644
--- a/arch/powerpc/sysdev/qe_lib/gpio.c
+++ b/arch/powerpc/sysdev/qe_lib/gpio.c
@@ -138,8 +138,8 @@
 struct qe_pin *qe_pin_request(struct device_node *np, int index)
 {
 	struct qe_pin *qe_pin;
-	struct device_node *gc;
-	struct of_gpio_chip *of_gc = NULL;
+	struct device_node *gpio_np;
+	struct gpio_chip *gc;
 	struct of_mm_gpio_chip *mm_gc;
 	struct qe_gpio_chip *qe_gc;
 	int err;
@@ -155,40 +155,40 @@
 	}
 
 	err = of_parse_phandles_with_args(np, "gpios", "#gpio-cells", index,
-					  &gc, &gpio_spec);
+					  &gpio_np, &gpio_spec);
 	if (err) {
 		pr_debug("%s: can't parse gpios property\n", __func__);
 		goto err0;
 	}
 
-	if (!of_device_is_compatible(gc, "fsl,mpc8323-qe-pario-bank")) {
+	if (!of_device_is_compatible(gpio_np, "fsl,mpc8323-qe-pario-bank")) {
 		pr_debug("%s: tried to get a non-qe pin\n", __func__);
 		err = -EINVAL;
 		goto err1;
 	}
 
-	of_gc = gc->data;
-	if (!of_gc) {
+	gc = gpio_np->data;
+	if (!gc) {
 		pr_debug("%s: gpio controller %s isn't registered\n",
-			 np->full_name, gc->full_name);
+			 np->full_name, gpio_np->full_name);
 		err = -ENODEV;
 		goto err1;
 	}
 
-	gpio_cells = of_get_property(gc, "#gpio-cells", &size);
+	gpio_cells = of_get_property(gpio_np, "#gpio-cells", &size);
 	if (!gpio_cells || size != sizeof(*gpio_cells) ||
-			*gpio_cells != of_gc->gpio_cells) {
+			*gpio_cells != gc->of_gpio_n_cells) {
 		pr_debug("%s: wrong #gpio-cells for %s\n",
-			 np->full_name, gc->full_name);
+			 np->full_name, gpio_np->full_name);
 		err = -EINVAL;
 		goto err1;
 	}
 
-	err = of_gc->xlate(of_gc, np, gpio_spec, NULL);
+	err = gc->of_xlate(gc, np, gpio_spec, NULL);
 	if (err < 0)
 		goto err1;
 
-	mm_gc = to_of_mm_gpio_chip(&of_gc->gc);
+	mm_gc = to_of_mm_gpio_chip(gc);
 	qe_gc = to_qe_gpio_chip(mm_gc);
 
 	spin_lock_irqsave(&qe_gc->lock, flags);
@@ -206,7 +206,7 @@
 	if (!err)
 		return qe_pin;
 err1:
-	of_node_put(gc);
+	of_node_put(gpio_np);
 err0:
 	kfree(qe_pin);
 	pr_debug("%s failed with status %d\n", __func__, err);
@@ -307,7 +307,6 @@
 		int ret;
 		struct qe_gpio_chip *qe_gc;
 		struct of_mm_gpio_chip *mm_gc;
-		struct of_gpio_chip *of_gc;
 		struct gpio_chip *gc;
 
 		qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL);
@@ -319,11 +318,10 @@
 		spin_lock_init(&qe_gc->lock);
 
 		mm_gc = &qe_gc->mm_gc;
-		of_gc = &mm_gc->of_gc;
-		gc = &of_gc->gc;
+		gc = &mm_gc->gc;
 
 		mm_gc->save_regs = qe_gpio_save_regs;
-		of_gc->gpio_cells = 2;
+		gc->of_gpio_n_cells = 2;
 		gc->ngpio = QE_PIO_PINS;
 		gc->direction_input = qe_gpio_dir_in;
 		gc->direction_output = qe_gpio_dir_out;
diff --git a/arch/powerpc/sysdev/simple_gpio.c b/arch/powerpc/sysdev/simple_gpio.c
index d5fb173..b7559aa 100644
--- a/arch/powerpc/sysdev/simple_gpio.c
+++ b/arch/powerpc/sysdev/simple_gpio.c
@@ -91,7 +91,6 @@
 	int ret;
 	struct u8_gpio_chip *u8_gc;
 	struct of_mm_gpio_chip *mm_gc;
-	struct of_gpio_chip *of_gc;
 	struct gpio_chip *gc;
 
 	u8_gc = kzalloc(sizeof(*u8_gc), GFP_KERNEL);
@@ -101,11 +100,10 @@
 	spin_lock_init(&u8_gc->lock);
 
 	mm_gc = &u8_gc->mm_gc;
-	of_gc = &mm_gc->of_gc;
-	gc = &of_gc->gc;
+	gc = &mm_gc->gc;
 
 	mm_gc->save_regs = u8_gpio_save_regs;
-	of_gc->gpio_cells = 2;
+	gc->of_gpio_n_cells = 2;
 	gc->ngpio = 8;
 	gc->direction_input = u8_gpio_dir_in;
 	gc->direction_output = u8_gpio_dir_out;
diff --git a/drivers/gpio/xilinx_gpio.c b/drivers/gpio/xilinx_gpio.c
index b8fa65b..2993c40 100644
--- a/drivers/gpio/xilinx_gpio.c
+++ b/drivers/gpio/xilinx_gpio.c
@@ -161,14 +161,12 @@
 static int __devinit xgpio_of_probe(struct device_node *np)
 {
 	struct xgpio_instance *chip;
-	struct of_gpio_chip *ofchip;
 	int status = 0;
 	const u32 *tree_info;
 
 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
 	if (!chip)
 		return -ENOMEM;
-	ofchip = &chip->mmchip.of_gc;
 
 	/* Update GPIO state shadow register with default value */
 	tree_info = of_get_property(np, "xlnx,dout-default", NULL);
@@ -182,21 +180,21 @@
 		chip->gpio_dir = *tree_info;
 
 	/* Check device node and parent device node for device width */
-	ofchip->gc.ngpio = 32; /* By default assume full GPIO controller */
+	chip->mmchip.gc.ngpio = 32; /* By default assume full GPIO controller */
 	tree_info = of_get_property(np, "xlnx,gpio-width", NULL);
 	if (!tree_info)
 		tree_info = of_get_property(np->parent,
 					    "xlnx,gpio-width", NULL);
 	if (tree_info)
-		ofchip->gc.ngpio = *tree_info;
+		chip->mmchip.gc.ngpio = *tree_info;
 
 	spin_lock_init(&chip->gpio_lock);
 
-	ofchip->gpio_cells = 2;
-	ofchip->gc.direction_input = xgpio_dir_in;
-	ofchip->gc.direction_output = xgpio_dir_out;
-	ofchip->gc.get = xgpio_get;
-	ofchip->gc.set = xgpio_set;
+	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;
+	chip->mmchip.gc.set = xgpio_set;
 
 	chip->mmchip.save_regs = xgpio_save_regs;
 
diff --git a/drivers/of/gpio.c b/drivers/of/gpio.c
index a1b31a4..fde53a3 100644
--- a/drivers/of/gpio.c
+++ b/drivers/of/gpio.c
@@ -33,32 +33,32 @@
 		      enum of_gpio_flags *flags)
 {
 	int ret;
-	struct device_node *gc;
-	struct of_gpio_chip *of_gc = NULL;
+	struct device_node *gpio_np;
+	struct gpio_chip *gc;
 	int size;
 	const void *gpio_spec;
 	const __be32 *gpio_cells;
 
 	ret = of_parse_phandles_with_args(np, "gpios", "#gpio-cells", index,
-					  &gc, &gpio_spec);
+					  &gpio_np, &gpio_spec);
 	if (ret) {
 		pr_debug("%s: can't parse gpios property\n", __func__);
 		goto err0;
 	}
 
-	of_gc = gc->data;
-	if (!of_gc) {
+	gc = gpio_np->data;
+	if (!gc) {
 		pr_debug("%s: gpio controller %s isn't registered\n",
-			 np->full_name, gc->full_name);
+			 np->full_name, gpio_np->full_name);
 		ret = -ENODEV;
 		goto err1;
 	}
 
-	gpio_cells = of_get_property(gc, "#gpio-cells", &size);
+	gpio_cells = of_get_property(gpio_np, "#gpio-cells", &size);
 	if (!gpio_cells || size != sizeof(*gpio_cells) ||
-			be32_to_cpup(gpio_cells) != of_gc->gpio_cells) {
+			be32_to_cpup(gpio_cells) != gc->of_gpio_n_cells) {
 		pr_debug("%s: wrong #gpio-cells for %s\n",
-			 np->full_name, gc->full_name);
+			 np->full_name, gpio_np->full_name);
 		ret = -EINVAL;
 		goto err1;
 	}
@@ -67,13 +67,13 @@
 	if (flags)
 		*flags = 0;
 
-	ret = of_gc->xlate(of_gc, np, gpio_spec, flags);
+	ret = gc->of_xlate(gc, np, gpio_spec, flags);
 	if (ret < 0)
 		goto err1;
 
-	ret += of_gc->gc.base;
+	ret += gc->base;
 err1:
-	of_node_put(gc);
+	of_node_put(gpio_np);
 err0:
 	pr_debug("%s exited with status %d\n", __func__, ret);
 	return ret;
@@ -116,7 +116,7 @@
 
 /**
  * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags
- * @of_gc:	pointer to the of_gpio_chip structure
+ * @gc:		pointer to the gpio_chip structure
  * @np:		device node of the GPIO chip
  * @gpio_spec:	gpio specifier as found in the device tree
  * @flags:	a flags pointer to fill in
@@ -125,8 +125,8 @@
  * gpio chips. This function performs only one sanity check: whether gpio
  * is less than ngpios (that is specified in the gpio_chip).
  */
-int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, struct device_node *np,
-			 const void *gpio_spec, enum of_gpio_flags *flags)
+int of_gpio_simple_xlate(struct gpio_chip *gc, struct device_node *np,
+			 const void *gpio_spec, u32 *flags)
 {
 	const __be32 *gpio = gpio_spec;
 	const u32 n = be32_to_cpup(gpio);
@@ -137,12 +137,12 @@
 	 * number and the flags from a single gpio cell -- this is possible,
 	 * but not recommended).
 	 */
-	if (of_gc->gpio_cells < 2) {
+	if (gc->of_gpio_n_cells < 2) {
 		WARN_ON(1);
 		return -EINVAL;
 	}
 
-	if (n > of_gc->gc.ngpio)
+	if (n > gc->ngpio)
 		return -EINVAL;
 
 	if (flags)
@@ -161,10 +161,8 @@
  *
  * 1) In the gpio_chip structure:
  *    - all the callbacks
- *
- * 2) In the of_gpio_chip structure:
- *    - gpio_cells
- *    - xlate callback (optional)
+ *    - of_gpio_n_cells
+ *    - of_xlate callback (optional)
  *
  * 3) In the of_mm_gpio_chip structure:
  *    - save_regs callback (optional)
@@ -177,8 +175,7 @@
 		       struct of_mm_gpio_chip *mm_gc)
 {
 	int ret = -ENOMEM;
-	struct of_gpio_chip *of_gc = &mm_gc->of_gc;
-	struct gpio_chip *gc = &of_gc->gc;
+	struct gpio_chip *gc = &mm_gc->gc;
 
 	gc->label = kstrdup(np->full_name, GFP_KERNEL);
 	if (!gc->label)
@@ -190,13 +187,14 @@
 
 	gc->base = -1;
 
-	if (!of_gc->xlate)
-		of_gc->xlate = of_gpio_simple_xlate;
+	if (!gc->of_xlate)
+		gc->of_xlate = of_gpio_simple_xlate;
 
 	if (mm_gc->save_regs)
 		mm_gc->save_regs(mm_gc);
 
-	np->data = of_gc;
+	np->data = &mm_gc->gc;
+	mm_gc->gc.of_node = np;
 
 	ret = gpiochip_add(gc);
 	if (ret)
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index 4f3d75e..af2544e 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -31,6 +31,7 @@
 struct device;
 struct seq_file;
 struct module;
+struct device_node;
 
 /**
  * struct gpio_chip - abstract a GPIO controller
@@ -106,6 +107,17 @@
 	const char		*const *names;
 	unsigned		can_sleep:1;
 	unsigned		exported:1;
+
+#if defined(CONFIG_OF_GPIO)
+	/*
+	 * If CONFIG_OF is enabled, then all GPIO controllers described in the
+	 * device tree automatically may have an OF translation
+	 */
+	struct device_node *of_node;
+	int of_gpio_n_cells;
+	int (*of_xlate)(struct gpio_chip *gc, struct device_node *np,
+		        const void *gpio_spec, u32 *flags);
+#endif
 };
 
 extern const char *gpiochip_is_requested(struct gpio_chip *chip,
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index fc2472c..460d681 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -33,34 +33,17 @@
 #ifdef CONFIG_OF_GPIO
 
 /*
- * Generic OF GPIO chip
- */
-struct of_gpio_chip {
-	struct gpio_chip gc;
-	int gpio_cells;
-	int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np,
-		     const void *gpio_spec, enum of_gpio_flags *flags);
-};
-
-static inline struct of_gpio_chip *to_of_gpio_chip(struct gpio_chip *gc)
-{
-	return container_of(gc, struct of_gpio_chip, gc);
-}
-
-/*
  * OF GPIO chip for memory mapped banks
  */
 struct of_mm_gpio_chip {
-	struct of_gpio_chip of_gc;
+	struct gpio_chip gc;
 	void (*save_regs)(struct of_mm_gpio_chip *mm_gc);
 	void __iomem *regs;
 };
 
 static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
 {
-	struct of_gpio_chip *of_gc = to_of_gpio_chip(gc);
-
-	return container_of(of_gc, struct of_mm_gpio_chip, of_gc);
+	return container_of(gc, struct of_mm_gpio_chip, gc);
 }
 
 extern int of_get_gpio_flags(struct device_node *np, int index,
@@ -69,11 +52,9 @@
 
 extern int of_mm_gpiochip_add(struct device_node *np,
 			      struct of_mm_gpio_chip *mm_gc);
-extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc,
-				struct device_node *np,
-				const void *gpio_spec,
-				enum of_gpio_flags *flags);
-#else
+extern int of_gpio_simple_xlate(struct gpio_chip *gc, struct device_node *np,
+				const void *gpio_spec, u32 *flags);
+#else /* CONFIG_OF_GPIO */
 
 /* Drivers may not strictly depend on the GPIO support, so let them link. */
 static inline int of_get_gpio_flags(struct device_node *np, int index,