[PATCH v6] ARM/mx35/3ds: gpio: add mc9s08dz60 gpio function

wu guoxing b39297 at freescale.com
Thu Nov 10 05:53:46 EST 2011


we only use the gpio function of mc9s08dz60 mcu chip, so just
add the gpio driver, as this mcu will never be used in other board.

Signed-off-by: Wu Guoxing <b39297 at freescale.com>
---
changes since v5:
	1. do not set i2c client data to NULL in probe&remove as i2c core will handle it.
	2. return error code to i2c core in remove function as i2c-core will depend on it to 
	set i2c client data to NULL.

changes since v4:
	1. set i2c client data to NULL only when gpiochip_remove success.

changes since v3:
	1. set i2c client data before gpiochip_add
	2. return error value in mc9s08dz60_direction_output

Changes since v1:
	1. add can_sleep = 1
	2. removed some useless return checks and local variable
	3. removed the static variable for i2c client.
	4. make init&exit function static

 drivers/gpio/Kconfig           |    6 ++
 drivers/gpio/Makefile          |    1 +
 drivers/gpio/gpio-mc9s08dz60.c |  174 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 181 insertions(+), 0 deletions(-)
 create mode 100644 drivers/gpio/gpio-mc9s08dz60.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index d539efd..7f6beee 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -487,4 +487,10 @@ config GPIO_TPS65910
 	help
 	  Select this option to enable GPIO driver for the TPS65910
 	  chip family.
+
+config GPIO_MC9S08DZ60
+	bool "MX35 3DS BOARD MC9S08DZ60 GPIO functions"
+	depends on I2C && MACH_MX35_3DS
+	help
+	  Select this to enable the MC9S08DZ60 GPIO driver
 endif
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 9588948..85b8799 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -60,3 +60,4 @@ obj-$(CONFIG_GPIO_WM831X)	+= gpio-wm831x.o
 obj-$(CONFIG_GPIO_WM8350)	+= gpio-wm8350.o
 obj-$(CONFIG_GPIO_WM8994)	+= gpio-wm8994.o
 obj-$(CONFIG_GPIO_XILINX)	+= gpio-xilinx.o
+obj-$(CONFIG_GPIO_MC9S08DZ60) += gpio-mc9s08dz60.o
diff --git a/drivers/gpio/gpio-mc9s08dz60.c b/drivers/gpio/gpio-mc9s08dz60.c
new file mode 100644
index 0000000..f0bc59a
--- /dev/null
+++ b/drivers/gpio/gpio-mc9s08dz60.c
@@ -0,0 +1,174 @@
+/*
+ * Copyright 2009-2011 Freescale Semiconductor, Inc. All Rights Reserved.
+ *
+ * Author: Wu Guoxing <b39297 at freescale.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+
+#define GPIO_GROUP_NUM 2
+#define GPIO_NUM_PER_GROUP 8
+#define GPIO_NUM (GPIO_GROUP_NUM*GPIO_NUM_PER_GROUP)
+
+struct mc9s08dz60 {
+	struct i2c_client *client;
+	struct gpio_chip chip;
+};
+
+static struct mc9s08dz60 *to_mc9s08dz60(struct gpio_chip *gc)
+{
+	return container_of(gc, struct mc9s08dz60, chip);
+}
+
+
+static void gpio_to_reg_and_bit(int offset, u8 *reg, u8 *bit)
+{
+	*reg = 0x20 + offset / GPIO_NUM_PER_GROUP;
+	*bit = offset % GPIO_NUM_PER_GROUP;
+}
+
+static int mc9s08dz60_get_value(struct gpio_chip *gc, unsigned offset)
+{
+	int ret = 0;
+	u8 reg, bit;
+	s32 value;
+	struct mc9s08dz60 *mc9s = to_mc9s08dz60(gc);
+
+	gpio_to_reg_and_bit(offset, &reg, &bit);
+	value = i2c_smbus_read_byte_data(mc9s->client, reg);
+	if (value >= 0)
+		ret = (value >> bit) & 0x1;
+
+	return ret;
+}
+
+static int _mc9s08dz60_set(struct mc9s08dz60 *mc9s, unsigned offset, int val)
+{
+	u8 reg, bit;
+	s32 value;
+
+	gpio_to_reg_and_bit(offset, &reg, &bit);
+	value = i2c_smbus_read_byte_data(mc9s->client, reg);
+	if (value >= 0) {
+		if (val)
+			value |= 1 << bit;
+		else
+			value &= ~(1 << bit);
+
+		return i2c_smbus_write_byte_data(mc9s->client, reg, value);
+	} else
+		return value;
+
+}
+
+
+static void mc9s08dz60_set_value(struct gpio_chip *gc, unsigned offset, int val)
+{
+	struct mc9s08dz60 *mc9s = to_mc9s08dz60(gc);
+
+	_mc9s08dz60_set(mc9s, offset, val);
+}
+
+static int mc9s08dz60_direction_output(struct gpio_chip *gc,
+				       unsigned offset, int val)
+{
+	struct mc9s08dz60 *mc9s = to_mc9s08dz60(gc);
+
+	return _mc9s08dz60_set(mc9s, offset, val);
+}
+
+static int mc9s08dz60_probe(struct i2c_client *client,
+			    const struct i2c_device_id *id)
+{
+	int ret = 0;
+	struct mc9s08dz60 *mc9s;
+
+	mc9s = kzalloc(sizeof(*mc9s), GFP_KERNEL);
+	if (!mc9s)
+		return -ENOMEM;
+
+	mc9s->chip.label = client->name;
+	mc9s->chip.base = -1;
+	mc9s->chip.dev = &client->dev;
+	mc9s->chip.owner = THIS_MODULE;
+	mc9s->chip.ngpio = GPIO_NUM;
+	mc9s->chip.can_sleep = 1;
+	mc9s->chip.get = mc9s08dz60_get_value;
+	mc9s->chip.set = mc9s08dz60_set_value;
+	mc9s->chip.direction_output = mc9s08dz60_direction_output;
+	mc9s->client = client;
+	i2c_set_clientdata(client, mc9s);
+
+	ret = gpiochip_add(&mc9s->chip);
+	if (ret)
+		goto error;
+
+	return 0;
+
+error:
+	kfree(mc9s);
+	return ret;
+}
+
+static int mc9s08dz60_remove(struct i2c_client *client)
+{
+	struct mc9s08dz60 *mc9s;
+	int ret;
+
+	mc9s = i2c_get_clientdata(client);
+
+	ret = gpiochip_remove(&mc9s->chip);
+	if (!ret)
+		kfree(mc9s);
+
+	return ret;
+
+}
+
+static const struct i2c_device_id mc9s08dz60_id[] = {
+	{"mc9s08dz60", 0},
+	{},
+};
+
+MODULE_DEVICE_TABLE(i2c, mc9s08dz60_id);
+
+static struct i2c_driver mc9s08dz60_i2c_driver = {
+	.driver = {.owner = THIS_MODULE,
+		   .name = "mc9s08dz60",
+		   },
+	.probe = mc9s08dz60_probe,
+	.remove = mc9s08dz60_remove,
+	.id_table = mc9s08dz60_id,
+};
+
+static int __init mc9s08dz60_init(void)
+{
+	return i2c_add_driver(&mc9s08dz60_i2c_driver);
+}
+
+static void __exit mc9s08dz60_exit(void)
+{
+	i2c_del_driver(&mc9s08dz60_i2c_driver);
+}
+
+module_init(mc9s08dz60_init);
+module_exit(mc9s08dz60_exit);
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc."
+		"Wu Guoxing <b39297 at freescale.com>");
+MODULE_DESCRIPTION("mc9s08dz60 gpio function on mx35 3ds board");
+MODULE_LICENSE("GPL v2");
-- 
1.7.1





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