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>

arch/microblaze/kernel/reset.c

@@ -24,8 +24,8 @@ static int of_reset_gpio_handle(void)
 	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 @@ static int of_reset_gpio_handle(void)
 		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:

arch/powerpc/platforms/52xx/mpc52xx_gpio.c

@@ -152,21 +152,21 @@ static int __devinit mpc52xx_wkup_gpiochip_probe(struct of_device *ofdev,
 {
 	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)
@@ -315,22 +315,22 @@ static int __devinit mpc52xx_simple_gpiochip_probe(struct of_device *ofdev,
 					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;
 
 	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            = 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)

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);
 

arch/powerpc/platforms/83xx/mcu_mpc8349emitx.c

@@ -37,7 +37,7 @@ struct mcu {
 	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_power_off(void)
 
 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_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 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 @@ static int mcu_gpiochip_add(struct mcu *mcu)
 	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 @@ static int mcu_gpiochip_remove(struct mcu *mcu)
 {
 	int ret;
 
-	ret = gpiochip_remove(&mcu->of_gc.gc);
+	ret = gpiochip_remove(&mcu->gc);
 	if (ret)
 		return ret;
 	of_node_put(mcu->np);

arch/powerpc/platforms/86xx/gef_gpio.c

@@ -118,12 +118,12 @@ static int __init gef_gpio_init(void)
 		}
 
 		/* 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 @@ static int __init gef_gpio_init(void)
 		}
 
 		/* 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);

arch/powerpc/sysdev/cpm1.c

@@ -621,7 +621,6 @@ int cpm1_gpiochip_add16(struct device_node *np)
 {
 	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 @@ int cpm1_gpiochip_add16(struct device_node *np)
 	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 @@ int cpm1_gpiochip_add32(struct device_node *np)
 {
 	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 @@ int cpm1_gpiochip_add32(struct device_node *np)
 	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;

arch/powerpc/sysdev/cpm_common.c

@@ -325,7 +325,6 @@ int cpm2_gpiochip_add32(struct device_node *np)
 {
 	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 @@ int cpm2_gpiochip_add32(struct device_node *np)
 	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;

arch/powerpc/sysdev/mpc8xxx_gpio.c

@@ -257,7 +257,6 @@ static void __init mpc8xxx_add_controller(struct device_node *np)
 {
 	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 @@ static void __init mpc8xxx_add_controller(struct device_node *np)
 	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;

arch/powerpc/sysdev/ppc4xx_gpio.c

@@ -181,7 +181,6 @@ static int __init ppc4xx_add_gpiochips(void)
 		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 @@ static int __init ppc4xx_add_gpiochips(void)
 		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;