diff options
Diffstat (limited to 'drivers/gpio/gpio-mc9s08dz60.c')
| -rw-r--r-- | drivers/gpio/gpio-mc9s08dz60.c | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-mc9s08dz60.c b/drivers/gpio/gpio-mc9s08dz60.c new file mode 100644 index 000000000..d8d846d21 --- /dev/null +++ b/drivers/gpio/gpio-mc9s08dz60.c @@ -0,0 +1,121 @@ +/* + * Copyright 2009-2012 Freescale Semiconductor, Inc. All Rights Reserved. + * + * Author: Wu Guoxing <b39297@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/init.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/gpio/driver.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 void mc9s_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) +{ + u8 reg, bit; + s32 value; + struct mc9s08dz60 *mc9s = gpiochip_get_data(gc); + + mc9s_gpio_to_reg_and_bit(offset, ®, &bit); + value = i2c_smbus_read_byte_data(mc9s->client, reg); + + return (value >= 0) ? (value >> bit) & 0x1 : 0; +} + +static int mc9s08dz60_set(struct mc9s08dz60 *mc9s, unsigned offset, int val) +{ + u8 reg, bit; + s32 value; + + mc9s_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 = gpiochip_get_data(gc); + + mc9s08dz60_set(mc9s, offset, val); +} + +static int mc9s08dz60_direction_output(struct gpio_chip *gc, + unsigned offset, int val) +{ + struct mc9s08dz60 *mc9s = gpiochip_get_data(gc); + + return mc9s08dz60_set(mc9s, offset, val); +} + +static int mc9s08dz60_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct mc9s08dz60 *mc9s; + + mc9s = devm_kzalloc(&client->dev, sizeof(*mc9s), GFP_KERNEL); + if (!mc9s) + return -ENOMEM; + + mc9s->chip.label = client->name; + mc9s->chip.base = -1; + mc9s->chip.parent = &client->dev; + mc9s->chip.owner = THIS_MODULE; + mc9s->chip.ngpio = GPIO_NUM; + mc9s->chip.can_sleep = true; + 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); + + return devm_gpiochip_add_data(&client->dev, &mc9s->chip, mc9s); +} + +static const struct i2c_device_id mc9s08dz60_id[] = { + {"mc9s08dz60", 0}, + {}, +}; + +static struct i2c_driver mc9s08dz60_i2c_driver = { + .driver = { + .name = "mc9s08dz60", + }, + .probe = mc9s08dz60_probe, + .id_table = mc9s08dz60_id, +}; +builtin_i2c_driver(mc9s08dz60_i2c_driver); |