drivers/gpio/gpio-tps6586x.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * TI TPS6586x GPIO driver
   4  *
   5  * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
   6  * Author: Laxman dewangan <ldewangan@nvidia.com>
   7  *
   8  * Based on tps6586x.c
   9  * Copyright (c) 2010 CompuLab Ltd.
  10  * Mike Rapoport <mike@compulab.co.il>
  11  */
  12
  13 #include <linux/errno.h>
  14 #include <linux/gpio/driver.h>
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/mfd/tps6586x.h>
  18 #include <linux/of_device.h>
  19 #include <linux/platform_device.h>
  20
  21 /* GPIO control registers */
  22 #define TPS6586X_GPIOSET1       0x5d
  23 #define TPS6586X_GPIOSET2       0x5e
  24
  25 struct tps6586x_gpio {
  26         struct gpio_chip gpio_chip;
  27         struct device *parent;
  28 };
  29
  30 static int tps6586x_gpio_get(struct gpio_chip *gc, unsigned offset)
  31 {
  32         struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
  33         uint8_t val;
  34         int ret;
  35
  36         ret = tps6586x_read(tps6586x_gpio->parent, TPS6586X_GPIOSET2, &val);
  37         if (ret)
  38                 return ret;
  39
  40         return !!(val & (1 << offset));
  41 }
  42
  43 static void tps6586x_gpio_set(struct gpio_chip *gc, unsigned offset,
  44                               int value)
  45 {
  46         struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
  47
  48         tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET2,
  49                         value << offset, 1 << offset);
  50 }
  51
  52 static int tps6586x_gpio_output(struct gpio_chip *gc, unsigned offset,
  53                                 int value)
  54 {
  55         struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
  56         uint8_t val, mask;
  57
  58         tps6586x_gpio_set(gc, offset, value);
  59
  60         val = 0x1 << (offset * 2);
  61         mask = 0x3 << (offset * 2);
  62
  63         return tps6586x_update(tps6586x_gpio->parent, TPS6586X_GPIOSET1,
  64                                 val, mask);
  65 }
  66
  67 static int tps6586x_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
  68 {
  69         struct tps6586x_gpio *tps6586x_gpio = gpiochip_get_data(gc);
  70
  71         return tps6586x_irq_get_virq(tps6586x_gpio->parent,
  72                                 TPS6586X_INT_PLDO_0 + offset);
  73 }
  74
  75 static int tps6586x_gpio_probe(struct platform_device *pdev)
  76 {
  77         struct tps6586x_platform_data *pdata;
  78         struct tps6586x_gpio *tps6586x_gpio;
  79
  80         device_set_node(&pdev->dev, dev_fwnode(pdev->dev.parent));
  81
  82         pdata = dev_get_platdata(pdev->dev.parent);
  83         tps6586x_gpio = devm_kzalloc(&pdev->dev,
  84                                 sizeof(*tps6586x_gpio), GFP_KERNEL);
  85         if (!tps6586x_gpio)
  86                 return -ENOMEM;
  87
  88         tps6586x_gpio->parent = pdev->dev.parent;
  89
  90         tps6586x_gpio->gpio_chip.owner = THIS_MODULE;
  91         tps6586x_gpio->gpio_chip.label = pdev->name;
  92         tps6586x_gpio->gpio_chip.parent = &pdev->dev;
  93         tps6586x_gpio->gpio_chip.ngpio = 4;
  94         tps6586x_gpio->gpio_chip.can_sleep = true;
  95
  96         /* FIXME: add handling of GPIOs as dedicated inputs */
  97         tps6586x_gpio->gpio_chip.direction_output = tps6586x_gpio_output;
  98         tps6586x_gpio->gpio_chip.set    = tps6586x_gpio_set;
  99         tps6586x_gpio->gpio_chip.get    = tps6586x_gpio_get;
 100         tps6586x_gpio->gpio_chip.to_irq = tps6586x_gpio_to_irq;
 101
 102         if (pdata && pdata->gpio_base)
 103                 tps6586x_gpio->gpio_chip.base = pdata->gpio_base;
 104         else
 105                 tps6586x_gpio->gpio_chip.base = -1;
 106
 107         return devm_gpiochip_add_data(&pdev->dev, &tps6586x_gpio->gpio_chip,
 108                                       tps6586x_gpio);
 109 }
 110
 111 static struct platform_driver tps6586x_gpio_driver = {
 112         .driver.name    = "tps6586x-gpio",
 113         .probe          = tps6586x_gpio_probe,
 114 };
 115
 116 static int __init tps6586x_gpio_init(void)
 117 {
 118         return platform_driver_register(&tps6586x_gpio_driver);
 119 }
 120 subsys_initcall(tps6586x_gpio_init);