LXR linux/drivers/gpio/gpio-twl6040.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Access to GPOs on TWL6040 chip
   4 *
   5 * Copyright (C) 2012 Texas Instruments, Inc.
   6 *
   7 * Authors:
   8 *      Sergio Aguirre <saaguirre@ti.com>
   9 *      Peter Ujfalusi <peter.ujfalusi@ti.com>
  10 */
  11
  12#include <linux/module.h>
  13#include <linux/init.h>
  14#include <linux/kthread.h>
  15#include <linux/irq.h>
  16#include <linux/gpio/driver.h>
  17#include <linux/platform_device.h>
  18#include <linux/bitops.h>
  19#include <linux/of.h>
  20
  21#include <linux/mfd/twl6040.h>
  22
  23static int twl6040gpo_get(struct gpio_chip *chip, unsigned offset)
  24{
  25        struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);
  26        int ret = 0;
  27
  28        ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);
  29        if (ret < 0)
  30                return ret;
  31
  32        return !!(ret & BIT(offset));
  33}
  34
  35static int twl6040gpo_get_direction(struct gpio_chip *chip, unsigned offset)
  36{
  37        return GPIO_LINE_DIRECTION_OUT;
  38}
  39
  40static int twl6040gpo_direction_out(struct gpio_chip *chip, unsigned offset,
  41                                    int value)
  42{
  43        /* This only drives GPOs, and can't change direction */
  44        return 0;
  45}
  46
  47static void twl6040gpo_set(struct gpio_chip *chip, unsigned offset, int value)
  48{
  49        struct twl6040 *twl6040 = dev_get_drvdata(chip->parent->parent);
  50        int ret;
  51        u8 gpoctl;
  52
  53        ret = twl6040_reg_read(twl6040, TWL6040_REG_GPOCTL);
  54        if (ret < 0)
  55                return;
  56
  57        if (value)
  58                gpoctl = ret | BIT(offset);
  59        else
  60                gpoctl = ret & ~BIT(offset);
  61
  62        twl6040_reg_write(twl6040, TWL6040_REG_GPOCTL, gpoctl);
  63}
  64
  65static struct gpio_chip twl6040gpo_chip = {
  66        .label                  = "twl6040",
  67        .owner                  = THIS_MODULE,
  68        .get                    = twl6040gpo_get,
  69        .direction_output       = twl6040gpo_direction_out,
  70        .get_direction          = twl6040gpo_get_direction,
  71        .set                    = twl6040gpo_set,
  72        .can_sleep              = true,
  73};
  74
  75/*----------------------------------------------------------------------*/
  76
  77static int gpo_twl6040_probe(struct platform_device *pdev)
  78{
  79        struct device *twl6040_core_dev = pdev->dev.parent;
  80        struct twl6040 *twl6040 = dev_get_drvdata(twl6040_core_dev);
  81        int ret;
  82
  83        twl6040gpo_chip.base = -1;
  84
  85        if (twl6040_get_revid(twl6040) < TWL6041_REV_ES2_0)
  86                twl6040gpo_chip.ngpio = 3; /* twl6040 have 3 GPO */
  87        else
  88                twl6040gpo_chip.ngpio = 1; /* twl6041 have 1 GPO */
  89
  90        twl6040gpo_chip.parent = &pdev->dev;
  91#ifdef CONFIG_OF_GPIO
  92        twl6040gpo_chip.of_node = twl6040_core_dev->of_node;
  93#endif
  94
  95        ret = devm_gpiochip_add_data(&pdev->dev, &twl6040gpo_chip, NULL);
  96        if (ret < 0) {
  97                dev_err(&pdev->dev, "could not register gpiochip, %d\n", ret);
  98                twl6040gpo_chip.ngpio = 0;
  99        }
 100
 101        return ret;
 102}
 103
 104/* Note:  this hardware lives inside an I2C-based multi-function device. */
 105MODULE_ALIAS("platform:twl6040-gpo");
 106
 107static struct platform_driver gpo_twl6040_driver = {
 108        .driver = {
 109                .name   = "twl6040-gpo",
 110        },
 111        .probe          = gpo_twl6040_probe,
 112};
 113
 114module_platform_driver(gpo_twl6040_driver);
 115
 116MODULE_AUTHOR("Texas Instruments, Inc.");
 117MODULE_DESCRIPTION("GPO interface for TWL6040");
 118MODULE_LICENSE("GPL");
 119