drivers/core/syscon-uclass.c

   1 /*
   2  * Copyright (C) 2015 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #include <common.h>
   9 #include <syscon.h>
  10 #include <dm.h>
  11 #include <errno.h>
  12 #include <regmap.h>
  13 #include <dm/device-internal.h>
  14 #include <dm/lists.h>
  15 #include <dm/root.h>
  16 #include <linux/err.h>
  17
  18 struct regmap *syscon_get_regmap(struct udevice *dev)
  19 {
  20         struct syscon_uc_info *priv;
  21
  22         if (device_get_uclass_id(dev) != UCLASS_SYSCON)
  23                 return ERR_PTR(-ENOEXEC);
  24         priv = dev_get_uclass_priv(dev);
  25         return priv->regmap;
  26 }
  27
  28 static int syscon_pre_probe(struct udevice *dev)
  29 {
  30         struct syscon_uc_info *priv = dev_get_uclass_priv(dev);
  31
  32         /*
  33          * With OF_PLATDATA we really have no way of knowing the format of
  34          * the device-specific platform data. So we assume that it starts with
  35          * a 'reg' member, and this holds a single address and size. Drivers
  36          * using OF_PLATDATA will need to ensure that this is true.
  37          */
  38 #if CONFIG_IS_ENABLED(OF_PLATDATA)
  39         struct syscon_base_platdata *plat = dev_get_platdata(dev);
  40
  41         return regmap_init_mem_platdata(dev, plat->reg, ARRAY_SIZE(plat->reg),
  42                                         &priv->regmap);
  43 #else
  44         return regmap_init_mem(dev, &priv->regmap);
  45 #endif
  46 }
  47
  48 int syscon_get_by_driver_data(ulong driver_data, struct udevice **devp)
  49 {
  50         struct udevice *dev;
  51         struct uclass *uc;
  52         int ret;
  53
  54         *devp = NULL;
  55         ret = uclass_get(UCLASS_SYSCON, &uc);
  56         if (ret)
  57                 return ret;
  58         uclass_foreach_dev(dev, uc) {
  59                 if (dev->driver_data == driver_data) {
  60                         *devp = dev;
  61                         return device_probe(dev);
  62                 }
  63         }
  64
  65         return -ENODEV;
  66 }
  67
  68 struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data)
  69 {
  70         struct syscon_uc_info *priv;
  71         struct udevice *dev;
  72         int ret;
  73
  74         ret = syscon_get_by_driver_data(driver_data, &dev);
  75         if (ret)
  76                 return ERR_PTR(ret);
  77         priv = dev_get_uclass_priv(dev);
  78
  79         return priv->regmap;
  80 }
  81
  82 void *syscon_get_first_range(ulong driver_data)
  83 {
  84         struct regmap *map;
  85
  86         map = syscon_get_regmap_by_driver_data(driver_data);
  87         if (IS_ERR(map))
  88                 return map;
  89         return regmap_get_range(map, 0);
  90 }
  91
  92 UCLASS_DRIVER(syscon) = {
  93         .id             = UCLASS_SYSCON,
  94         .name           = "syscon",
  95         .per_device_auto_alloc_size = sizeof(struct syscon_uc_info),
  96         .pre_probe = syscon_pre_probe,
  97 };
  98
  99 static const struct udevice_id generic_syscon_ids[] = {
 100         { .compatible = "syscon" },
 101         { }
 102 };
 103
 104 U_BOOT_DRIVER(generic_syscon) = {
 105         .name   = "syscon",
 106         .id     = UCLASS_SYSCON,
 107 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
 108         .bind           = dm_scan_fdt_dev,
 109 #endif
 110         .of_match = generic_syscon_ids,
 111 };