linux/drivers/gpio/gpio-twl6040.c

125 lines
3.3 KiB
C

/*
* Access to GPOs on TWL6040 chip
*
* Copyright (C) 2012 Texas Instruments, Inc.
*
* Authors:
* Sergio Aguirre <saaguirre@ti.com>
* Peter Ujfalusi <peter.ujfalusi@ti.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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kthread.h>
#include <linux/irq.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/mfd/twl6040.h>
static int twl6040gpo_get(struct gpio_chip *chip, unsigned offset)
{
struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);
int ret = 0;
ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);
if (ret < 0)
return ret;
return (ret >> offset) & 1;
}
static int twl6040gpo_direction_out(struct gpio_chip *chip, unsigned offset,
int value)
{
/* This only drives GPOs, and can't change direction */
return 0;
}
static void twl6040gpo_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);
int ret;
u8 gpoctl;
ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);
if (ret < 0)
return;
if (value)
gpoctl = ret | (1 << offset);
else
gpoctl = ret & ~(1 << offset);
twl6040_reg_write(twl6040, TWL6040_REG_GPOCTL, gpoctl);
}
static struct gpio_chip twl6040gpo_chip = {
.label = "twl6040",
.owner = THIS_MODULE,
.get = twl6040gpo_get,
.direction_output = twl6040gpo_direction_out,
.set = twl6040gpo_set,
.can_sleep = true,
};
/*----------------------------------------------------------------------*/
static int gpo_twl6040_probe(struct platform_device *pdev)
{
struct device *twl6040_core_dev = pdev->dev.parent;
struct twl6040 *twl6040 = dev_get_drvdata(twl6040_core_dev);
int ret;
twl6040gpo_chip.base = -1;
if (twl6040_get_revid(twl6040) < TWL6041_REV_ES2_0)
twl6040gpo_chip.ngpio = 3; /* twl6040 have 3 GPO */
else
twl6040gpo_chip.ngpio = 1; /* twl6041 have 1 GPO */
twl6040gpo_chip.parent = &pdev->dev;
#ifdef CONFIG_OF_GPIO
twl6040gpo_chip.of_node = twl6040_core_dev->of_node;
#endif
ret = devm_gpiochip_add_data(&pdev->dev, &twl6040gpo_chip, NULL);
if (ret < 0) {
dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
twl6040gpo_chip.ngpio = 0;
}
return ret;
}
/* Note: this hardware lives inside an I2C-based multi-function device. */
MODULE_ALIAS("platform:twl6040-gpo");
static struct platform_driver gpo_twl6040_driver = {
.driver = {
.name = "twl6040-gpo",
},
.probe = gpo_twl6040_probe,
};
module_platform_driver(gpo_twl6040_driver);
MODULE_AUTHOR("Texas Instruments, Inc.");
MODULE_DESCRIPTION("GPO interface for TWL6040");
MODULE_LICENSE("GPL");