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 struct regmap *syscon_regmap_lookup_by_phandle(struct udevice *dev, 49 const char *name) 50 { 51 struct udevice *syscon; 52 struct regmap *r; 53 int err; 54 55 err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev, 56 name, &syscon); 57 if (err) 58 return ERR_PTR(err); 59 60 r = syscon_get_regmap(syscon); 61 if (!r) 62 return ERR_PTR(-ENODEV); 63 64 return r; 65 } 66 67 int syscon_get_by_driver_data(ulong driver_data, struct udevice **devp) 68 { 69 struct udevice *dev; 70 struct uclass *uc; 71 int ret; 72 73 *devp = NULL; 74 ret = uclass_get(UCLASS_SYSCON, &uc); 75 if (ret) 76 return ret; 77 uclass_foreach_dev(dev, uc) { 78 if (dev->driver_data == driver_data) { 79 *devp = dev; 80 return device_probe(dev); 81 } 82 } 83 84 return -ENODEV; 85 } 86 87 struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data) 88 { 89 struct syscon_uc_info *priv; 90 struct udevice *dev; 91 int ret; 92 93 ret = syscon_get_by_driver_data(driver_data, &dev); 94 if (ret) 95 return ERR_PTR(ret); 96 priv = dev_get_uclass_priv(dev); 97 98 return priv->regmap; 99 } 100 101 void *syscon_get_first_range(ulong driver_data) 102 { 103 struct regmap *map; 104 105 map = syscon_get_regmap_by_driver_data(driver_data); 106 if (IS_ERR(map)) 107 return map; 108 return regmap_get_range(map, 0); 109 } 110 111 UCLASS_DRIVER(syscon) = { 112 .id = UCLASS_SYSCON, 113 .name = "syscon", 114 .per_device_auto_alloc_size = sizeof(struct syscon_uc_info), 115 .pre_probe = syscon_pre_probe, 116 }; 117 118 static const struct udevice_id generic_syscon_ids[] = { 119 { .compatible = "syscon" }, 120 { } 121 }; 122 123 U_BOOT_DRIVER(generic_syscon) = { 124 .name = "syscon", 125 .id = UCLASS_SYSCON, 126 #if !CONFIG_IS_ENABLED(OF_PLATDATA) 127 .bind = dm_scan_fdt_dev, 128 #endif 129 .of_match = generic_syscon_ids, 130 }; 131