drivers/gpio/gpio-adp5520.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * GPIO driver for Analog Devices ADP5520 MFD PMICs
   4  *
   5  * Copyright 2009 Analog Devices Inc.
   6  */
   7
   8 #include <linux/module.h>
   9 #include <linux/slab.h>
  10 #include <linux/kernel.h>
  11 #include <linux/init.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/mfd/adp5520.h>
  14 #include <linux/gpio/driver.h>
  15
  16 struct adp5520_gpio {
  17         struct device *master;
  18         struct gpio_chip gpio_chip;
  19         unsigned char lut[ADP5520_MAXGPIOS];
  20         unsigned long output;
  21 };
  22
  23 static int adp5520_gpio_get_value(struct gpio_chip *chip, unsigned off)
  24 {
  25         struct adp5520_gpio *dev;
  26         uint8_t reg_val;
  27
  28         dev = gpiochip_get_data(chip);
  29
  30         /*
  31          * There are dedicated registers for GPIO IN/OUT.
  32          * Make sure we return the right value, even when configured as output
  33          */
  34
  35         if (test_bit(off, &dev->output))
  36                 adp5520_read(dev->master, ADP5520_GPIO_OUT, &reg_val);
  37         else
  38                 adp5520_read(dev->master, ADP5520_GPIO_IN, &reg_val);
  39
  40         return !!(reg_val & dev->lut[off]);
  41 }
  42
  43 static void adp5520_gpio_set_value(struct gpio_chip *chip,
  44                 unsigned off, int val)
  45 {
  46         struct adp5520_gpio *dev;
  47         dev = gpiochip_get_data(chip);
  48
  49         if (val)
  50                 adp5520_set_bits(dev->master, ADP5520_GPIO_OUT, dev->lut[off]);
  51         else
  52                 adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT, dev->lut[off]);
  53 }
  54
  55 static int adp5520_gpio_direction_input(struct gpio_chip *chip, unsigned off)
  56 {
  57         struct adp5520_gpio *dev;
  58         dev = gpiochip_get_data(chip);
  59
  60         clear_bit(off, &dev->output);
  61
  62         return adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_2,
  63                                 dev->lut[off]);
  64 }
  65
  66 static int adp5520_gpio_direction_output(struct gpio_chip *chip,
  67                 unsigned off, int val)
  68 {
  69         struct adp5520_gpio *dev;
  70         int ret = 0;
  71         dev = gpiochip_get_data(chip);
  72
  73         set_bit(off, &dev->output);
  74
  75         if (val)
  76                 ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_OUT,
  77                                         dev->lut[off]);
  78         else
  79                 ret |= adp5520_clr_bits(dev->master, ADP5520_GPIO_OUT,
  80                                         dev->lut[off]);
  81
  82         ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_CFG_2,
  83                                         dev->lut[off]);
  84
  85         return ret;
  86 }
  87
  88 static int adp5520_gpio_probe(struct platform_device *pdev)
  89 {
  90         struct adp5520_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
  91         struct adp5520_gpio *dev;
  92         struct gpio_chip *gc;
  93         int ret, i, gpios;
  94         unsigned char ctl_mask = 0;
  95
  96         if (pdata == NULL) {
  97                 dev_err(&pdev->dev, "missing platform data\n");
  98                 return -ENODEV;
  99         }
 100
 101         if (pdev->id != ID_ADP5520) {
 102                 dev_err(&pdev->dev, "only ADP5520 supports GPIO\n");
 103                 return -ENODEV;
 104         }
 105
 106         dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 107         if (dev == NULL)
 108                 return -ENOMEM;
 109
 110         dev->master = pdev->dev.parent;
 111
 112         for (gpios = 0, i = 0; i < ADP5520_MAXGPIOS; i++)
 113                 if (pdata->gpio_en_mask & (1 << i))
 114                         dev->lut[gpios++] = 1 << i;
 115
 116         if (gpios < 1)
 117                 return -EINVAL;
 118
 119         gc = &dev->gpio_chip;
 120         gc->direction_input  = adp5520_gpio_direction_input;
 121         gc->direction_output = adp5520_gpio_direction_output;
 122         gc->get = adp5520_gpio_get_value;
 123         gc->set = adp5520_gpio_set_value;
 124         gc->can_sleep = true;
 125
 126         gc->base = pdata->gpio_start;
 127         gc->ngpio = gpios;
 128         gc->label = pdev->name;
 129         gc->owner = THIS_MODULE;
 130
 131         ret = adp5520_clr_bits(dev->master, ADP5520_GPIO_CFG_1,
 132                 pdata->gpio_en_mask);
 133
 134         if (pdata->gpio_en_mask & ADP5520_GPIO_C3)
 135                 ctl_mask |= ADP5520_C3_MODE;
 136
 137         if (pdata->gpio_en_mask & ADP5520_GPIO_R3)
 138                 ctl_mask |= ADP5520_R3_MODE;
 139
 140         if (ctl_mask)
 141                 ret = adp5520_set_bits(dev->master, ADP5520_LED_CONTROL,
 142                         ctl_mask);
 143
 144         ret |= adp5520_set_bits(dev->master, ADP5520_GPIO_PULLUP,
 145                 pdata->gpio_pullup_mask);
 146
 147         if (ret) {
 148                 dev_err(&pdev->dev, "failed to write\n");
 149                 return ret;
 150         }
 151
 152         return devm_gpiochip_add_data(&pdev->dev, &dev->gpio_chip, dev);
 153 }
 154
 155 static struct platform_driver adp5520_gpio_driver = {
 156         .driver = {
 157                 .name   = "adp5520-gpio",
 158         },
 159         .probe          = adp5520_gpio_probe,
 160 };
 161
 162 module_platform_driver(adp5520_gpio_driver);
 163
 164 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
 165 MODULE_DESCRIPTION("GPIO ADP5520 Driver");
 166 MODULE_LICENSE("GPL");
 167 MODULE_ALIAS("platform:adp5520-gpio");