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 }; 111