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Subject[PATCH 5/7] of/gpio: implement of_dev_gpiochip_{add,remove} calls
And let the gpiolib forward all dev_gpiochip_ calls to of_ versions, there
we can glue the gpiochips with the device tree.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
---
arch/powerpc/include/asm/gpio.h | 7 +++-
drivers/of/gpio.c | 75 +++++++++++++++++++++++++++++++++++++-
include/linux/of_gpio.h | 7 ++++
3 files changed, 86 insertions(+), 3 deletions(-)
diff --git a/arch/powerpc/include/asm/gpio.h b/arch/powerpc/include/asm/gpio.h
index ea04632..92610b1 100644
--- a/arch/powerpc/include/asm/gpio.h
+++ b/arch/powerpc/include/asm/gpio.h
@@ -14,8 +14,13 @@
#ifndef __ASM_POWERPC_GPIO_H
#define __ASM_POWERPC_GPIO_H

-#include <linux/errno.h>
+/* Tell the gpiolib that we'll handle the dev_gpiochip_* calls. */
+#define __dev_gpiochip_add of_dev_gpiochip_add
+#define __dev_gpiochip_remove of_dev_gpiochip_remove
+
#include <asm-generic/gpio.h>
+#include <linux/errno.h>
+#include <linux/of_gpio.h>

#ifdef CONFIG_GPIOLIB

diff --git a/drivers/of/gpio.c b/drivers/of/gpio.c
index 7cd7301..b6f56af 100644
--- a/drivers/of/gpio.c
+++ b/drivers/of/gpio.c
@@ -12,12 +12,33 @@
*/

#include <linux/kernel.h>
+#include <linux/device.h>
#include <linux/errno.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <asm/prom.h>

+static struct gpio_chip *of_gc_to_gc(struct of_gpio_chip *of_gc)
+{
+ /*
+ * Currently there are two ways to register OF GPIO controllers:
+ *
+ * 1. Allocating the of_gpio_chip structure and passing the
+ * &of_gc->gc pointer to the gpiochip_add. (Can use container_of
+ * to convert the gpio_chip to the of_gpio_chip.)
+ *
+ * 2. Allocating and registering the gpio_chip structure separately
+ * from the of_gpio_chip. (Since two allocations are separate,
+ * container_of won't work.)
+ *
+ * As time goes by we may kill the first option.
+ */
+ if (of_gc->chip)
+ return of_gc->chip;
+ return &of_gc->gc;
+}
+
/**
* of_get_gpio - Get a GPIO number from the device tree to use with GPIO API
* @np: device node to get GPIO from
@@ -63,7 +84,7 @@ int of_get_gpio(struct device_node *np, int index)
if (ret < 0)
goto err1;

- ret += of_gc->gc.base;
+ ret += of_gc_to_gc(of_gc)->base;
err1:
of_node_put(gc);
err0:
@@ -87,7 +108,7 @@ int of_gpio_simple_xlate(struct of_gpio_chip *of_gc, struct device_node *np,
{
const u32 *gpio = gpio_spec;

- if (*gpio > of_gc->gc.ngpio)
+ if (*gpio > of_gc_to_gc(of_gc)->ngpio)
return -EINVAL;

return *gpio;
@@ -161,3 +182,53 @@ err0:
return ret;
}
EXPORT_SYMBOL(of_mm_gpiochip_add);
+
+int of_dev_gpiochip_add(struct device *dev, struct gpio_chip *chip)
+{
+ struct device_node *np = dev_archdata_get_node(&dev->archdata);
+ struct of_gpio_chip *of_gc;
+ int ret;
+
+ if (!np || np->data)
+ return -EINVAL;
+
+ of_gc = kzalloc(sizeof(*of_gc), GFP_KERNEL);
+ if (!of_gc)
+ return -ENOMEM;
+ /*
+ * NOTE: for simple cases we use the simple_xlate with 2 cells scheme.
+ * You can always overwrite it with an exceptions list that would
+ * match on of_device_is_compatible().
+ */
+ of_gc->gpio_cells = 2;
+ of_gc->xlate = of_gpio_simple_xlate;
+
+ chip->dev = dev;
+ of_gc->chip = chip;
+ np->data = of_gc;
+
+ ret = gpiochip_add(chip);
+ if (ret)
+ goto err_gpiochip_add;
+ return 0;
+
+err_gpiochip_add:
+ np->data = NULL;
+ chip->dev = NULL;
+ kfree(of_gc);
+ return ret;
+}
+EXPORT_SYMBOL(of_dev_gpiochip_add);
+
+int of_dev_gpiochip_remove(struct device *dev, struct gpio_chip *chip)
+{
+ struct device_node *np = dev_archdata_get_node(&dev->archdata);
+ int ret;
+
+ ret = gpiochip_remove(chip);
+ if (ret)
+ return ret;
+ np->data = NULL;
+ return 0;
+}
+EXPORT_SYMBOL(of_dev_gpiochip_remove);
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index 67db101..273cd79 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -14,16 +14,21 @@
#ifndef __LINUX_OF_GPIO_H
#define __LINUX_OF_GPIO_H

+#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/gpio.h>

#ifdef CONFIG_OF_GPIO

+struct device_node;
+struct device;
+
/*
* Generic OF GPIO chip
*/
struct of_gpio_chip {
struct gpio_chip gc;
+ struct gpio_chip *chip;
int gpio_cells;
int (*xlate)(struct of_gpio_chip *of_gc, struct device_node *np,
const void *gpio_spec);
@@ -53,6 +58,8 @@ static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
extern int of_get_gpio(struct device_node *np, int index);
extern int of_mm_gpiochip_add(struct device_node *np,
struct of_mm_gpio_chip *mm_gc);
+extern int of_dev_gpiochip_add(struct device *dev, struct gpio_chip *chip);
+extern int of_dev_gpiochip_remove(struct device *dev, struct gpio_chip *chip);
extern int of_gpio_simple_xlate(struct of_gpio_chip *of_gc,
struct device_node *np,
const void *gpio_spec);
--
1.5.6.3


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