diff options
Diffstat (limited to 'drivers/gpio/gpio-twl6040.c')
| -rw-r--r-- | drivers/gpio/gpio-twl6040.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-twl6040.c b/drivers/gpio/gpio-twl6040.c new file mode 100644 index 000000000..c946e7eef --- /dev/null +++ b/drivers/gpio/gpio-twl6040.c @@ -0,0 +1,133 @@ +/* + * 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 struct gpio_chip twl6040gpo_chip; + +static int twl6040gpo_get(struct gpio_chip *chip, unsigned offset) +{ + struct twl6040 *twl6040 = dev_get_drvdata(chip->dev->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->dev->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.dev = &pdev->dev; +#ifdef CONFIG_OF_GPIO + twl6040gpo_chip.of_node = twl6040_core_dev->of_node; +#endif + + ret = gpiochip_add(&twl6040gpo_chip); + if (ret < 0) { + dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret); + twl6040gpo_chip.ngpio = 0; + } + + return ret; +} + +static int gpo_twl6040_remove(struct platform_device *pdev) +{ + gpiochip_remove(&twl6040gpo_chip); + return 0; +} + +/* 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, + .remove = gpo_twl6040_remove, +}; + +module_platform_driver(gpo_twl6040_driver); + +MODULE_AUTHOR("Texas Instruments, Inc."); +MODULE_DESCRIPTION("GPO interface for TWL6040"); +MODULE_LICENSE("GPL"); |