[PATCH v4] ARM/mx35/3ds: gpio: add mc9s08dz60 gpio function

[Wu Guoxing]

Hi Grant:
    I have send out a new patch according to your commnets, please review.
  
    Thanks for the comments!

Wu Guoxing

On Mon, Jan 23, 2012 at 06:13:06AM -0700, Grant Likely wrote:
> On Thu, Nov 10, 2011 at 10:24:10AM +0800, y at shlinux1.ap.freescale.net wrote:
> > From: wu guoxing <b39297 at freescale.com>
> > 
> > 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 v3:
> > 	1. set i2c client data before gpiochip_add
> > 	2. return error value in mc9s08dz60_direction_output
> > v3 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 |  177 ++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 184 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
> 
> This list is sorted alphabetically.  Please keep it that way.
> 
> > diff --git a/drivers/gpio/gpio-mc9s08dz60.c b/drivers/gpio/gpio-mc9s08dz60.c
> > new file mode 100644
> > index 0000000..0122ef8
> > --- /dev/null
> > +++ b/drivers/gpio/gpio-mc9s08dz60.c
> > @@ -0,0 +1,177 @@
> > +/*
> > + * 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)
> 
> static inline
> 
> > +{
> > +	return container_of(gc, struct mc9s08dz60, chip);
> > +}
> > +
> > +
> > +static void gpio_to_reg_and_bit(int offset, u8 *reg, u8 *bit)
> 
> Protect against namespace collisions and put a mc9s... prefix on this
> function.
> 
> > +{
> > +	*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;
> 
> 	return (value >= 0) ? (value >> bit) & 1 : 0;
> 
> > +}
> > +
> > +static int _mc9s08dz60_set(struct mc9s08dz60 *mc9s, unsigned offset, int val)
> 
> Single leader underscore '_' is reserved.  Use either two underscores
> '__' or none at all.
> 
> > +{
> > +	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:
> 
> Tip: insert one space before a label so that diff will show the
> function name on context output instead of the label name.
> 
> > +	i2c_set_clientdata(client, NULL);
> > +	kfree(mc9s);
> > +	return ret;
> > +}
> > +
> > +static int mc9s08dz60_remove(struct i2c_client *client)
> > +{
> > +	struct mc9s08dz60 *mc9s;
> > +	int ret;
> > +
> > +	mc9s = i2c_get_clientdata(client);
> > +
> > +	i2c_set_clientdata(client, NULL);
> > +
> > +	ret = gpiochip_remove(&mc9s->chip);
> > +	if (!ret)
> > +		kfree(mc9s);
> > +
> > +	return 0;
> > +
> > +}
> > +
> > +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",
> > +		   },
> 
> Please use this indentation for static initializers:
> 	.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_i2c_driver() is preferred now.
> 
> > +
> > +MODULE_AUTHOR("Freescale Semiconductor, Inc."
> > +		"Wu Guoxing <b39297 at freescale.com>");
> 
> There is no space between "...Inc." and "Wu...", which is probably not
> what you want.  :-)
> 
> Otherwise looks good.  One respin and it should be ready for merging.
> 
> g.
>