[PATCH v4] ARM/mx35/3ds: gpio: add mc9s08dz60 gpio function
Wu Guoxing-B39297
B39297 at freescale.com
Thu Nov 10 06:05:38 EST 2011
Hi Marc:
I changed the code to unset i2c client data just when gipochip_remove successes,
Otherwise, there will be problems next time the remove function is called.
Please review the v5 patch.
Thanks!
Best regards
Wu Guoxing
-----Original Message-----
From: Marc Kleine-Budde [mailto:mkl at pengutronix.de]
Sent: Thursday, November 10, 2011 6:14 PM
To: Wu Guoxing-B39297
Cc: linux-arm-kernel at lists.infradead.org; grant.likely at secretlab.ca; s.hauer at pengutronix.de; shawn.guo at linaro.org
Subject: Re: [PATCH v4] ARM/mx35/3ds: gpio: add mc9s08dz60 gpio function
On 11/10/2011 03:24 AM, wu guoxing wrote:
> 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
exchange the two in the remove function, too.
First shut down the gpio chip, then unset set i2c client data.
Marc
> 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
> 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) {
> + 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, ®, &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, ®, &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:
> + 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",
> + },
> + .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");
--
Pengutronix e.K. | Marc Kleine-Budde |
Industrial Linux Solutions | Phone: +49-231-2826-924 |
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