drivers/pinctrl/pinctrl-da850-pupd.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Pinconf driver for TI DA850/OMAP-L138/AM18XX pullup/pulldown groups
   4  *
   5  * Copyright (C) 2016  David Lechner
   6  */
   7
   8 #include <linux/bitops.h>
   9 #include <linux/device.h>
  10 #include <linux/io.h>
  11 #include <linux/ioport.h>
  12 #include <linux/mod_devicetable.h>
  13 #include <linux/module.h>
  14 #include <linux/pinctrl/pinconf.h>
  15 #include <linux/pinctrl/pinconf-generic.h>
  16 #include <linux/pinctrl/pinctrl.h>
  17 #include <linux/platform_device.h>
  18
  19 #define DA850_PUPD_ENA          0x00
  20 #define DA850_PUPD_SEL          0x04
  21
  22 struct da850_pupd_data {
  23         void __iomem *base;
  24         struct pinctrl_desc desc;
  25         struct pinctrl_dev *pinctrl;
  26 };
  27
  28 static const char * const da850_pupd_group_names[] = {
  29         "cp0", "cp1", "cp2", "cp3", "cp4", "cp5", "cp6", "cp7",
  30         "cp8", "cp9", "cp10", "cp11", "cp12", "cp13", "cp14", "cp15",
  31         "cp16", "cp17", "cp18", "cp19", "cp20", "cp21", "cp22", "cp23",
  32         "cp24", "cp25", "cp26", "cp27", "cp28", "cp29", "cp30", "cp31",
  33 };
  34
  35 static int da850_pupd_get_groups_count(struct pinctrl_dev *pctldev)
  36 {
  37         return ARRAY_SIZE(da850_pupd_group_names);
  38 }
  39
  40 static const char *da850_pupd_get_group_name(struct pinctrl_dev *pctldev,
  41                                              unsigned int selector)
  42 {
  43         return da850_pupd_group_names[selector];
  44 }
  45
  46 static int da850_pupd_get_group_pins(struct pinctrl_dev *pctldev,
  47                                      unsigned int selector,
  48                                      const unsigned int **pins,
  49                                      unsigned int *num_pins)
  50 {
  51         *num_pins = 0;
  52
  53         return 0;
  54 }
  55
  56 static const struct pinctrl_ops da850_pupd_pctlops = {
  57         .get_groups_count       = da850_pupd_get_groups_count,
  58         .get_group_name         = da850_pupd_get_group_name,
  59         .get_group_pins         = da850_pupd_get_group_pins,
  60         .dt_node_to_map         = pinconf_generic_dt_node_to_map_group,
  61         .dt_free_map            = pinconf_generic_dt_free_map,
  62 };
  63
  64 static int da850_pupd_pin_config_group_get(struct pinctrl_dev *pctldev,
  65                                            unsigned int selector,
  66                                            unsigned long *config)
  67 {
  68         struct da850_pupd_data *data = pinctrl_dev_get_drvdata(pctldev);
  69         enum pin_config_param param = pinconf_to_config_param(*config);
  70         u32 val;
  71         u16 arg;
  72
  73         val = readl(data->base + DA850_PUPD_ENA);
  74         arg = !!(~val & BIT(selector));
  75
  76         switch (param) {
  77         case PIN_CONFIG_BIAS_DISABLE:
  78                 break;
  79         case PIN_CONFIG_BIAS_PULL_UP:
  80         case PIN_CONFIG_BIAS_PULL_DOWN:
  81                 if (arg) {
  82                         /* bias is disabled */
  83                         arg = 0;
  84                         break;
  85                 }
  86                 val = readl(data->base + DA850_PUPD_SEL);
  87                 if (param == PIN_CONFIG_BIAS_PULL_DOWN)
  88                         val = ~val;
  89                 arg = !!(val & BIT(selector));
  90                 break;
  91         default:
  92                 return -EINVAL;
  93         }
  94
  95         *config = pinconf_to_config_packed(param, arg);
  96
  97         return 0;
  98 }
  99
 100 static int da850_pupd_pin_config_group_set(struct pinctrl_dev *pctldev,
 101                                            unsigned int selector,
 102                                            unsigned long *configs,
 103                                            unsigned int num_configs)
 104 {
 105         struct da850_pupd_data *data = pinctrl_dev_get_drvdata(pctldev);
 106         u32 ena, sel;
 107         enum pin_config_param param;
 108         int i;
 109
 110         ena = readl(data->base + DA850_PUPD_ENA);
 111         sel = readl(data->base + DA850_PUPD_SEL);
 112
 113         for (i = 0; i < num_configs; i++) {
 114                 param = pinconf_to_config_param(configs[i]);
 115
 116                 switch (param) {
 117                 case PIN_CONFIG_BIAS_DISABLE:
 118                         ena &= ~BIT(selector);
 119                         break;
 120                 case PIN_CONFIG_BIAS_PULL_UP:
 121                         ena |= BIT(selector);
 122                         sel |= BIT(selector);
 123                         break;
 124                 case PIN_CONFIG_BIAS_PULL_DOWN:
 125                         ena |= BIT(selector);
 126                         sel &= ~BIT(selector);
 127                         break;
 128                 default:
 129                         return -EINVAL;
 130                 }
 131         }
 132
 133         writel(sel, data->base + DA850_PUPD_SEL);
 134         writel(ena, data->base + DA850_PUPD_ENA);
 135
 136         return 0;
 137 }
 138
 139 static const struct pinconf_ops da850_pupd_confops = {
 140         .is_generic             = true,
 141         .pin_config_group_get   = da850_pupd_pin_config_group_get,
 142         .pin_config_group_set   = da850_pupd_pin_config_group_set,
 143 };
 144
 145 static int da850_pupd_probe(struct platform_device *pdev)
 146 {
 147         struct device *dev = &pdev->dev;
 148         struct da850_pupd_data *data;
 149
 150         data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 151         if (!data)
 152                 return -ENOMEM;
 153
 154         data->base = devm_platform_ioremap_resource(pdev, 0);
 155         if (IS_ERR(data->base)) {
 156                 dev_err(dev, "Could not map resource\n");
 157                 return PTR_ERR(data->base);
 158         }
 159
 160         data->desc.name = dev_name(dev);
 161         data->desc.pctlops = &da850_pupd_pctlops;
 162         data->desc.confops = &da850_pupd_confops;
 163         data->desc.owner = THIS_MODULE;
 164
 165         data->pinctrl = devm_pinctrl_register(dev, &data->desc, data);
 166         if (IS_ERR(data->pinctrl)) {
 167                 dev_err(dev, "Failed to register pinctrl\n");
 168                 return PTR_ERR(data->pinctrl);
 169         }
 170
 171         platform_set_drvdata(pdev, data);
 172
 173         return 0;
 174 }
 175
 176 static int da850_pupd_remove(struct platform_device *pdev)
 177 {
 178         return 0;
 179 }
 180
 181 static const struct of_device_id da850_pupd_of_match[] = {
 182         { .compatible = "ti,da850-pupd" },
 183         { }
 184 };
 185 MODULE_DEVICE_TABLE(of, da850_pupd_of_match);
 186
 187 static struct platform_driver da850_pupd_driver = {
 188         .driver = {
 189                 .name           = "ti-da850-pupd",
 190                 .of_match_table = da850_pupd_of_match,
 191         },
 192         .probe  = da850_pupd_probe,
 193         .remove = da850_pupd_remove,
 194 };
 195 module_platform_driver(da850_pupd_driver);
 196
 197 MODULE_AUTHOR("David Lechner <david@lechnology.com>");
 198 MODULE_DESCRIPTION("TI DA850/OMAP-L138/AM18XX pullup/pulldown configuration");
 199 MODULE_LICENSE("GPL");