1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2015 Google, Inc
4 * Written by Simon Glass <sjg@chromium.org>
7 #define LOG_CATEGORY UCLASS_SYSCON
15 #include <dm/device-internal.h>
16 #include <dm/device_compat.h>
19 #include <linux/err.h>
23 * This API requires the given device has already been bound to the syscon
24 * driver. For example,
26 * compatible = "syscon", "simple-mfd";
30 * compatible = "simple-mfd", "syscon";
32 * does not. The behavior is different from Linux.
34 struct regmap *syscon_get_regmap(struct udevice *dev)
36 struct syscon_uc_info *priv;
38 if (device_get_uclass_id(dev) != UCLASS_SYSCON)
39 return ERR_PTR(-ENOEXEC);
40 priv = dev_get_uclass_priv(dev);
44 static int syscon_pre_probe(struct udevice *dev)
46 struct syscon_uc_info *priv = dev_get_uclass_priv(dev);
48 /* Special case for PCI devices, which don't have a regmap */
49 if (device_get_uclass_id(dev->parent) == UCLASS_PCI)
53 * With OF_PLATDATA we really have no way of knowing the format of
54 * the device-specific platform data. So we assume that it starts with
55 * a 'reg' member, and this holds a single address and size. Drivers
56 * using OF_PLATDATA will need to ensure that this is true.
58 #if CONFIG_IS_ENABLED(OF_PLATDATA)
59 struct syscon_base_plat *plat = dev_get_plat(dev);
61 return regmap_init_mem_plat(dev, plat->reg, ARRAY_SIZE(plat->reg),
64 return regmap_init_mem(dev_ofnode(dev), &priv->regmap);
68 static int syscon_probe_by_ofnode(ofnode node, struct udevice **devp)
70 struct udevice *dev, *parent;
73 /* found node with "syscon" compatible, not bounded to SYSCON UCLASS */
74 if (!ofnode_device_is_compatible(node, "syscon")) {
75 log_debug("invalid compatible for syscon device\n");
79 /* bound to driver with same ofnode or to root if not found */
80 if (device_find_global_by_ofnode(node, &parent))
83 /* force bound to syscon class */
84 ret = device_bind_driver_to_node(parent, "syscon",
85 ofnode_get_name(node),
88 dev_dbg(dev, "unable to bound syscon device\n");
91 ret = device_probe(dev);
93 dev_dbg(dev, "unable to probe syscon device\n");
101 struct regmap *syscon_regmap_lookup_by_phandle(struct udevice *dev,
104 struct udevice *syscon;
110 err = uclass_get_device_by_phandle(UCLASS_SYSCON, dev,
113 /* found node with "syscon" compatible, not bounded to SYSCON */
114 err = ofnode_read_u32(dev_ofnode(dev), name, &phandle);
118 node = ofnode_get_by_phandle(phandle);
119 if (!ofnode_valid(node)) {
120 dev_dbg(dev, "unable to find syscon device\n");
121 return ERR_PTR(-EINVAL);
123 err = syscon_probe_by_ofnode(node, &syscon);
125 return ERR_PTR(-ENODEV);
128 r = syscon_get_regmap(syscon);
130 dev_dbg(dev, "unable to find regmap\n");
131 return ERR_PTR(-ENODEV);
137 int syscon_get_by_driver_data(ulong driver_data, struct udevice **devp)
143 ret = uclass_first_device_drvdata(UCLASS_SYSCON, driver_data, devp);
150 struct regmap *syscon_get_regmap_by_driver_data(ulong driver_data)
152 struct syscon_uc_info *priv;
156 ret = syscon_get_by_driver_data(driver_data, &dev);
159 priv = dev_get_uclass_priv(dev);
164 void *syscon_get_first_range(ulong driver_data)
168 map = syscon_get_regmap_by_driver_data(driver_data);
171 return regmap_get_range(map, 0);
174 UCLASS_DRIVER(syscon) = {
177 .per_device_auto = sizeof(struct syscon_uc_info),
178 .pre_probe = syscon_pre_probe,
181 static const struct udevice_id generic_syscon_ids[] = {
182 { .compatible = "syscon" },
186 U_BOOT_DRIVER(generic_syscon) = {
189 #if !CONFIG_IS_ENABLED(OF_PLATDATA)
190 .bind = dm_scan_fdt_dev,
192 .of_match = generic_syscon_ids,
196 * Linux-compatible syscon-to-regmap
197 * The syscon node can be bound to another driver, but still works
198 * as a syscon provider.
200 struct regmap *syscon_node_to_regmap(ofnode node)
205 if (uclass_get_device_by_ofnode(UCLASS_SYSCON, node, &dev))
206 if (syscon_probe_by_ofnode(node, &dev))
207 return ERR_PTR(-ENODEV);
209 r = syscon_get_regmap(dev);
211 dev_dbg(dev, "unable to find regmap\n");
212 return ERR_PTR(-ENODEV);