drivers/core/syscon-uclass.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (C) 2015 Google, Inc
   4  * Written by Simon Glass <sjg@chromium.org>
   5  */
   6
   7 #include <common.h>
   8 #include <syscon.h>
   9 #include <dm.h>
  10 #include <errno.h>
  11 #include <regmap.h>
  12 #include <dm/device-internal.h>
  13 #include <dm/lists.h>
  14 #include <dm/root.h>
  15 #include <linux/err.h>
  16
  17 struct regmap *syscon_get_regmap(struct udevice *dev)
  18 {
  19         struct syscon_uc_info *priv;
  20
  21         if (device_get_uclass_id(dev) != UCLASS_SYSCON)
  22                 return ERR_PTR(-ENOEXEC);
  23         priv = dev_get_uclass_priv(dev);
  24         return priv->regmap;
  25 }
  26
  27 static int syscon_pre_probe(struct udevice *dev)
  28 {
  29         struct syscon_uc_info *priv = dev_get_uclass_priv(dev);
  30
  31         /*
  32          * With OF_PLATDATA we really have no way of knowing the format of
  33          * the device-specific platform data. So we assume that it starts with
  34          * a 'reg' member, and this holds a single address and size. Drivers
  35          * using OF_PLATDATA will need to ensure that this is true.
  36          */
  37 #if CONFIG_IS_ENABLED(OF_PLATDATA)
  38         struct syscon_base_platdata *plat = dev_get_platdata(dev);
  39
  40         return regmap_init_mem_platdata(dev, plat->reg, ARRAY_SIZE(plat->reg),
  41                                         &priv->regmap);
  42 #else
  43         return regmap_init_mem(dev, &priv->regmap);
  44 #endif
  45 }
  46
  47 int syscon_get_by_driver_data(ulong driver_data, struct udevice **devp)
  48 {
  49         struct udevice *dev;
  50         struct uclass *uc;
  51         int ret;
  52
  53         *devp = NULL;
  54         ret = uclass_get(UCLASS_SYSCON, &uc);
  55         if (ret)
  56                 return ret;
  57         uclass_foreach_dev(dev, uc) {
  58                 if (dev->driver_data == driver_data) {
  59                         *devp = dev;
  60                         return device_probe(dev);
  61                 }
  62         }
  63
  64         return -ENODEV;
  65 }
  66
  67 struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data)
  68 {
  69         struct syscon_uc_info *priv;
  70         struct udevice *dev;
  71         int ret;
  72
  73         ret = syscon_get_by_driver_data(driver_data, &dev);
  74         if (ret)
  75                 return ERR_PTR(ret);
  76         priv = dev_get_uclass_priv(dev);
  77
  78         return priv->regmap;
  79 }
  80
  81 void *syscon_get_first_range(ulong driver_data)
  82 {
  83         struct regmap *map;
  84
  85         map = syscon_get_regmap_by_driver_data(driver_data);
  86         if (IS_ERR(map))
  87                 return map;
  88         return regmap_get_range(map, 0);
  89 }
  90
  91 UCLASS_DRIVER(syscon) = {
  92         .id             = UCLASS_SYSCON,
  93         .name           = "syscon",
  94         .per_device_auto_alloc_size = sizeof(struct syscon_uc_info),
  95         .pre_probe = syscon_pre_probe,
  96 };
  97
  98 static const struct udevice_id generic_syscon_ids[] = {
  99         { .compatible = "syscon" },
 100         { }
 101 };
 102
 103 U_BOOT_DRIVER(generic_syscon) = {
 104         .name   = "syscon",
 105         .id     = UCLASS_SYSCON,
 106 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
 107         .bind           = dm_scan_fdt_dev,
 108 #endif
 109         .of_match = generic_syscon_ids,
 110 };