drivers/gpio/gpio-tn48m.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Delta TN48M CPLD GPIO driver
   4  *
   5  * Copyright (C) 2021 Sartura Ltd.
   6  *
   7  * Author: Robert Marko <robert.marko@sartura.hr>
   8  */
   9
  10 #include <linux/device.h>
  11 #include <linux/gpio/driver.h>
  12 #include <linux/gpio/regmap.h>
  13 #include <linux/mod_devicetable.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/regmap.h>
  17
  18 enum tn48m_gpio_type {
  19         TN48M_GP0 = 1,
  20         TN48M_GPI,
  21 };
  22
  23 struct tn48m_gpio_config {
  24         int ngpio;
  25         int ngpio_per_reg;
  26         enum tn48m_gpio_type type;
  27 };
  28
  29 static const struct tn48m_gpio_config tn48m_gpo_config = {
  30         .ngpio = 4,
  31         .ngpio_per_reg = 4,
  32         .type = TN48M_GP0,
  33 };
  34
  35 static const struct tn48m_gpio_config tn48m_gpi_config = {
  36         .ngpio = 4,
  37         .ngpio_per_reg = 4,
  38         .type = TN48M_GPI,
  39 };
  40
  41 static int tn48m_gpio_probe(struct platform_device *pdev)
  42 {
  43         const struct tn48m_gpio_config *gpio_config;
  44         struct gpio_regmap_config config = {};
  45         struct regmap *regmap;
  46         u32 base;
  47         int ret;
  48
  49         if (!pdev->dev.parent)
  50                 return -ENODEV;
  51
  52         gpio_config = device_get_match_data(&pdev->dev);
  53         if (!gpio_config)
  54                 return -ENODEV;
  55
  56         ret = device_property_read_u32(&pdev->dev, "reg", &base);
  57         if (ret)
  58                 return ret;
  59
  60         regmap = dev_get_regmap(pdev->dev.parent, NULL);
  61         if (!regmap)
  62                 return -ENODEV;
  63
  64         config.regmap = regmap;
  65         config.parent = &pdev->dev;
  66         config.ngpio = gpio_config->ngpio;
  67         config.ngpio_per_reg = gpio_config->ngpio_per_reg;
  68         switch (gpio_config->type) {
  69         case TN48M_GP0:
  70                 config.reg_set_base = base;
  71                 break;
  72         case TN48M_GPI:
  73                 config.reg_dat_base = base;
  74                 break;
  75         default:
  76                 return -EINVAL;
  77         }
  78
  79         return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(&pdev->dev, &config));
  80 }
  81
  82 static const struct of_device_id tn48m_gpio_of_match[] = {
  83         { .compatible = "delta,tn48m-gpo", .data = &tn48m_gpo_config },
  84         { .compatible = "delta,tn48m-gpi", .data = &tn48m_gpi_config },
  85         { }
  86 };
  87 MODULE_DEVICE_TABLE(of, tn48m_gpio_of_match);
  88
  89 static struct platform_driver tn48m_gpio_driver = {
  90         .driver = {
  91                 .name = "delta-tn48m-gpio",
  92                 .of_match_table = tn48m_gpio_of_match,
  93         },
  94         .probe = tn48m_gpio_probe,
  95 };
  96 module_platform_driver(tn48m_gpio_driver);
  97
  98 MODULE_AUTHOR("Robert Marko <robert.marko@sartura.hr>");
  99 MODULE_DESCRIPTION("Delta TN48M CPLD GPIO driver");
 100 MODULE_LICENSE("GPL");