12874c5fdSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
287d68730SDong Aisheng /*
387d68730SDong Aisheng * System Control Driver
487d68730SDong Aisheng *
587d68730SDong Aisheng * Copyright (C) 2012 Freescale Semiconductor, Inc.
687d68730SDong Aisheng * Copyright (C) 2012 Linaro Ltd.
787d68730SDong Aisheng *
887d68730SDong Aisheng * Author: Dong Aisheng <dong.aisheng@linaro.org>
987d68730SDong Aisheng */
1087d68730SDong Aisheng
11a00406b7SFabrice Gasnier #include <linux/clk.h>
1287d68730SDong Aisheng #include <linux/err.h>
133bafc09eSBaolin Wang #include <linux/hwspinlock.h>
1487d68730SDong Aisheng #include <linux/io.h>
151345da73SPaul Gortmaker #include <linux/init.h>
16bdb0066dSPankaj Dubey #include <linux/list.h>
1787d68730SDong Aisheng #include <linux/of.h>
1887d68730SDong Aisheng #include <linux/of_address.h>
1987d68730SDong Aisheng #include <linux/of_platform.h>
2029f9b6cfSPawel Moll #include <linux/platform_data/syscon.h>
2187d68730SDong Aisheng #include <linux/platform_device.h>
2287d68730SDong Aisheng #include <linux/regmap.h>
237d1e3bd9SJeremy Kerr #include <linux/reset.h>
2475177deeSFabio Estevam #include <linux/mfd/syscon.h>
25bdb0066dSPankaj Dubey #include <linux/slab.h>
2687d68730SDong Aisheng
2787d68730SDong Aisheng static struct platform_driver syscon_driver;
2887d68730SDong Aisheng
29bdb0066dSPankaj Dubey static DEFINE_SPINLOCK(syscon_list_slock);
30bdb0066dSPankaj Dubey static LIST_HEAD(syscon_list);
31bdb0066dSPankaj Dubey
3287d68730SDong Aisheng struct syscon {
33bdb0066dSPankaj Dubey struct device_node *np;
3487d68730SDong Aisheng struct regmap *regmap;
357d1e3bd9SJeremy Kerr struct reset_control *reset;
36bdb0066dSPankaj Dubey struct list_head list;
3787d68730SDong Aisheng };
3887d68730SDong Aisheng
39c131045dSPhilipp Zabel static const struct regmap_config syscon_regmap_config = {
40bdb0066dSPankaj Dubey .reg_bits = 32,
41bdb0066dSPankaj Dubey .val_bits = 32,
42bdb0066dSPankaj Dubey .reg_stride = 4,
43bdb0066dSPankaj Dubey };
4487d68730SDong Aisheng
of_syscon_register(struct device_node * np,bool check_res)457d1e3bd9SJeremy Kerr static struct syscon *of_syscon_register(struct device_node *np, bool check_res)
46bdb0066dSPankaj Dubey {
47a00406b7SFabrice Gasnier struct clk *clk;
48bdb0066dSPankaj Dubey struct syscon *syscon;
49bdb0066dSPankaj Dubey struct regmap *regmap;
50bdb0066dSPankaj Dubey void __iomem *base;
51db2fb60cSDamien Riegel u32 reg_io_width;
52bdb0066dSPankaj Dubey int ret;
53bdb0066dSPankaj Dubey struct regmap_config syscon_config = syscon_regmap_config;
54ca668f0eSPhilipp Zabel struct resource res;
557d1e3bd9SJeremy Kerr struct reset_control *reset;
56bdb0066dSPankaj Dubey
57bdb0066dSPankaj Dubey syscon = kzalloc(sizeof(*syscon), GFP_KERNEL);
58bdb0066dSPankaj Dubey if (!syscon)
59bdb0066dSPankaj Dubey return ERR_PTR(-ENOMEM);
60bdb0066dSPankaj Dubey
61ca668f0eSPhilipp Zabel if (of_address_to_resource(np, 0, &res)) {
62ca668f0eSPhilipp Zabel ret = -ENOMEM;
63ca668f0eSPhilipp Zabel goto err_map;
64ca668f0eSPhilipp Zabel }
65ca668f0eSPhilipp Zabel
66452d0741SHector Martin base = of_iomap(np, 0);
67bdb0066dSPankaj Dubey if (!base) {
68bdb0066dSPankaj Dubey ret = -ENOMEM;
69bdb0066dSPankaj Dubey goto err_map;
70bdb0066dSPankaj Dubey }
71bdb0066dSPankaj Dubey
72ca4582c2SJason A. Donenfeld /* Parse the device's DT node for an endianness specification */
73ca4582c2SJason A. Donenfeld if (of_property_read_bool(np, "big-endian"))
74ca4582c2SJason A. Donenfeld syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
75ca4582c2SJason A. Donenfeld else if (of_property_read_bool(np, "little-endian"))
76ca4582c2SJason A. Donenfeld syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
77ca4582c2SJason A. Donenfeld else if (of_property_read_bool(np, "native-endian"))
78ca4582c2SJason A. Donenfeld syscon_config.val_format_endian = REGMAP_ENDIAN_NATIVE;
79ca4582c2SJason A. Donenfeld
80db2fb60cSDamien Riegel /*
81db2fb60cSDamien Riegel * search for reg-io-width property in DT. If it is not provided,
82db2fb60cSDamien Riegel * default to 4 bytes. regmap_init_mmio will return an error if values
83db2fb60cSDamien Riegel * are invalid so there is no need to check them here.
84db2fb60cSDamien Riegel */
85db2fb60cSDamien Riegel ret = of_property_read_u32(np, "reg-io-width", ®_io_width);
86db2fb60cSDamien Riegel if (ret)
87db2fb60cSDamien Riegel reg_io_width = 4;
88db2fb60cSDamien Riegel
893bafc09eSBaolin Wang ret = of_hwspin_lock_get_id(np, 0);
903bafc09eSBaolin Wang if (ret > 0 || (IS_ENABLED(CONFIG_HWSPINLOCK) && ret == 0)) {
913bafc09eSBaolin Wang syscon_config.use_hwlock = true;
923bafc09eSBaolin Wang syscon_config.hwlock_id = ret;
933bafc09eSBaolin Wang syscon_config.hwlock_mode = HWLOCK_IRQSTATE;
943bafc09eSBaolin Wang } else if (ret < 0) {
953bafc09eSBaolin Wang switch (ret) {
963bafc09eSBaolin Wang case -ENOENT:
973bafc09eSBaolin Wang /* Ignore missing hwlock, it's optional. */
983bafc09eSBaolin Wang break;
993bafc09eSBaolin Wang default:
1003bafc09eSBaolin Wang pr_err("Failed to retrieve valid hwlock: %d\n", ret);
101df561f66SGustavo A. R. Silva fallthrough;
1023bafc09eSBaolin Wang case -EPROBE_DEFER:
1033bafc09eSBaolin Wang goto err_regmap;
1043bafc09eSBaolin Wang }
1053bafc09eSBaolin Wang }
1063bafc09eSBaolin Wang
1077ff7d5ffSAndy Shevchenko syscon_config.name = kasprintf(GFP_KERNEL, "%pOFn@%pa", np, &res.start);
1083ef1130dSKunwu Chan if (!syscon_config.name) {
1093ef1130dSKunwu Chan ret = -ENOMEM;
1103ef1130dSKunwu Chan goto err_regmap;
1113ef1130dSKunwu Chan }
112db2fb60cSDamien Riegel syscon_config.reg_stride = reg_io_width;
113db2fb60cSDamien Riegel syscon_config.val_bits = reg_io_width * 8;
114ca668f0eSPhilipp Zabel syscon_config.max_register = resource_size(&res) - reg_io_width;
115db2fb60cSDamien Riegel
116bdb0066dSPankaj Dubey regmap = regmap_init_mmio(NULL, base, &syscon_config);
11756a11881SLimeng kfree(syscon_config.name);
118bdb0066dSPankaj Dubey if (IS_ERR(regmap)) {
119bdb0066dSPankaj Dubey pr_err("regmap init failed\n");
120bdb0066dSPankaj Dubey ret = PTR_ERR(regmap);
121bdb0066dSPankaj Dubey goto err_regmap;
122bdb0066dSPankaj Dubey }
123bdb0066dSPankaj Dubey
1247d1e3bd9SJeremy Kerr if (check_res) {
125a00406b7SFabrice Gasnier clk = of_clk_get(np, 0);
126a00406b7SFabrice Gasnier if (IS_ERR(clk)) {
127a00406b7SFabrice Gasnier ret = PTR_ERR(clk);
128a00406b7SFabrice Gasnier /* clock is optional */
129a00406b7SFabrice Gasnier if (ret != -ENOENT)
130a00406b7SFabrice Gasnier goto err_clk;
131a00406b7SFabrice Gasnier } else {
132a00406b7SFabrice Gasnier ret = regmap_mmio_attach_clk(regmap, clk);
133a00406b7SFabrice Gasnier if (ret)
1347d1e3bd9SJeremy Kerr goto err_attach_clk;
135a00406b7SFabrice Gasnier }
1367d1e3bd9SJeremy Kerr
1377d1e3bd9SJeremy Kerr reset = of_reset_control_get_optional_exclusive(np, NULL);
1387d1e3bd9SJeremy Kerr if (IS_ERR(reset)) {
1397d1e3bd9SJeremy Kerr ret = PTR_ERR(reset);
1407d1e3bd9SJeremy Kerr goto err_attach_clk;
1417d1e3bd9SJeremy Kerr }
1427d1e3bd9SJeremy Kerr
1437d1e3bd9SJeremy Kerr ret = reset_control_deassert(reset);
1447d1e3bd9SJeremy Kerr if (ret)
1457d1e3bd9SJeremy Kerr goto err_reset;
14639233b7cSPaul Cercueil }
147a00406b7SFabrice Gasnier
148bdb0066dSPankaj Dubey syscon->regmap = regmap;
149bdb0066dSPankaj Dubey syscon->np = np;
150bdb0066dSPankaj Dubey
151bdb0066dSPankaj Dubey spin_lock(&syscon_list_slock);
152bdb0066dSPankaj Dubey list_add_tail(&syscon->list, &syscon_list);
153bdb0066dSPankaj Dubey spin_unlock(&syscon_list_slock);
154bdb0066dSPankaj Dubey
155bdb0066dSPankaj Dubey return syscon;
156bdb0066dSPankaj Dubey
1577d1e3bd9SJeremy Kerr err_reset:
1587d1e3bd9SJeremy Kerr reset_control_put(reset);
1597d1e3bd9SJeremy Kerr err_attach_clk:
160a00406b7SFabrice Gasnier if (!IS_ERR(clk))
161a00406b7SFabrice Gasnier clk_put(clk);
162a00406b7SFabrice Gasnier err_clk:
163a00406b7SFabrice Gasnier regmap_exit(regmap);
164bdb0066dSPankaj Dubey err_regmap:
165bdb0066dSPankaj Dubey iounmap(base);
166bdb0066dSPankaj Dubey err_map:
167bdb0066dSPankaj Dubey kfree(syscon);
168bdb0066dSPankaj Dubey return ERR_PTR(ret);
16987d68730SDong Aisheng }
17087d68730SDong Aisheng
device_node_get_regmap(struct device_node * np,bool check_res)17139233b7cSPaul Cercueil static struct regmap *device_node_get_regmap(struct device_node *np,
1727d1e3bd9SJeremy Kerr bool check_res)
17387d68730SDong Aisheng {
174bdb0066dSPankaj Dubey struct syscon *entry, *syscon = NULL;
17587d68730SDong Aisheng
176bdb0066dSPankaj Dubey spin_lock(&syscon_list_slock);
17787d68730SDong Aisheng
178bdb0066dSPankaj Dubey list_for_each_entry(entry, &syscon_list, list)
179bdb0066dSPankaj Dubey if (entry->np == np) {
180bdb0066dSPankaj Dubey syscon = entry;
181bdb0066dSPankaj Dubey break;
182bdb0066dSPankaj Dubey }
183bdb0066dSPankaj Dubey
184bdb0066dSPankaj Dubey spin_unlock(&syscon_list_slock);
185bdb0066dSPankaj Dubey
186bdb0066dSPankaj Dubey if (!syscon)
1877d1e3bd9SJeremy Kerr syscon = of_syscon_register(np, check_res);
188bdb0066dSPankaj Dubey
189bdb0066dSPankaj Dubey if (IS_ERR(syscon))
190bdb0066dSPankaj Dubey return ERR_CAST(syscon);
19187d68730SDong Aisheng
19287d68730SDong Aisheng return syscon->regmap;
19387d68730SDong Aisheng }
19439233b7cSPaul Cercueil
device_node_to_regmap(struct device_node * np)19539233b7cSPaul Cercueil struct regmap *device_node_to_regmap(struct device_node *np)
19639233b7cSPaul Cercueil {
19739233b7cSPaul Cercueil return device_node_get_regmap(np, false);
19839233b7cSPaul Cercueil }
19939233b7cSPaul Cercueil EXPORT_SYMBOL_GPL(device_node_to_regmap);
20039233b7cSPaul Cercueil
syscon_node_to_regmap(struct device_node * np)20139233b7cSPaul Cercueil struct regmap *syscon_node_to_regmap(struct device_node *np)
20239233b7cSPaul Cercueil {
20339233b7cSPaul Cercueil if (!of_device_is_compatible(np, "syscon"))
20439233b7cSPaul Cercueil return ERR_PTR(-EINVAL);
20539233b7cSPaul Cercueil
20639233b7cSPaul Cercueil return device_node_get_regmap(np, true);
20739233b7cSPaul Cercueil }
20887d68730SDong Aisheng EXPORT_SYMBOL_GPL(syscon_node_to_regmap);
20987d68730SDong Aisheng
syscon_regmap_lookup_by_compatible(const char * s)21087d68730SDong Aisheng struct regmap *syscon_regmap_lookup_by_compatible(const char *s)
21187d68730SDong Aisheng {
21287d68730SDong Aisheng struct device_node *syscon_np;
21387d68730SDong Aisheng struct regmap *regmap;
21487d68730SDong Aisheng
21587d68730SDong Aisheng syscon_np = of_find_compatible_node(NULL, NULL, s);
21687d68730SDong Aisheng if (!syscon_np)
21787d68730SDong Aisheng return ERR_PTR(-ENODEV);
21887d68730SDong Aisheng
21987d68730SDong Aisheng regmap = syscon_node_to_regmap(syscon_np);
22087d68730SDong Aisheng of_node_put(syscon_np);
22187d68730SDong Aisheng
22287d68730SDong Aisheng return regmap;
22387d68730SDong Aisheng }
22487d68730SDong Aisheng EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible);
22587d68730SDong Aisheng
syscon_regmap_lookup_by_phandle(struct device_node * np,const char * property)22687d68730SDong Aisheng struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np,
22787d68730SDong Aisheng const char *property)
22887d68730SDong Aisheng {
22987d68730SDong Aisheng struct device_node *syscon_np;
23087d68730SDong Aisheng struct regmap *regmap;
23187d68730SDong Aisheng
23245330bb4SPankaj Dubey if (property)
23387d68730SDong Aisheng syscon_np = of_parse_phandle(np, property, 0);
23445330bb4SPankaj Dubey else
23545330bb4SPankaj Dubey syscon_np = np;
23645330bb4SPankaj Dubey
23787d68730SDong Aisheng if (!syscon_np)
23887d68730SDong Aisheng return ERR_PTR(-ENODEV);
23987d68730SDong Aisheng
24087d68730SDong Aisheng regmap = syscon_node_to_regmap(syscon_np);
241*1b01e66cSPeter Griffin
242*1b01e66cSPeter Griffin if (property)
24387d68730SDong Aisheng of_node_put(syscon_np);
24487d68730SDong Aisheng
24587d68730SDong Aisheng return regmap;
24687d68730SDong Aisheng }
24787d68730SDong Aisheng EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle);
24887d68730SDong Aisheng
syscon_regmap_lookup_by_phandle_args(struct device_node * np,const char * property,int arg_count,unsigned int * out_args)2496a24f567SOrson Zhai struct regmap *syscon_regmap_lookup_by_phandle_args(struct device_node *np,
2506a24f567SOrson Zhai const char *property,
2516a24f567SOrson Zhai int arg_count,
2526a24f567SOrson Zhai unsigned int *out_args)
2536a24f567SOrson Zhai {
2546a24f567SOrson Zhai struct device_node *syscon_np;
2556a24f567SOrson Zhai struct of_phandle_args args;
2566a24f567SOrson Zhai struct regmap *regmap;
2576a24f567SOrson Zhai unsigned int index;
2586a24f567SOrson Zhai int rc;
2596a24f567SOrson Zhai
2606a24f567SOrson Zhai rc = of_parse_phandle_with_fixed_args(np, property, arg_count,
2616a24f567SOrson Zhai 0, &args);
2626a24f567SOrson Zhai if (rc)
2636a24f567SOrson Zhai return ERR_PTR(rc);
2646a24f567SOrson Zhai
2656a24f567SOrson Zhai syscon_np = args.np;
2666a24f567SOrson Zhai if (!syscon_np)
2676a24f567SOrson Zhai return ERR_PTR(-ENODEV);
2686a24f567SOrson Zhai
2696a24f567SOrson Zhai regmap = syscon_node_to_regmap(syscon_np);
2706a24f567SOrson Zhai for (index = 0; index < arg_count; index++)
2716a24f567SOrson Zhai out_args[index] = args.args[index];
2726a24f567SOrson Zhai of_node_put(syscon_np);
2736a24f567SOrson Zhai
2746a24f567SOrson Zhai return regmap;
2756a24f567SOrson Zhai }
2766a24f567SOrson Zhai EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle_args);
2776a24f567SOrson Zhai
27886b9d170SEnric Balletbo i Serra /*
27986b9d170SEnric Balletbo i Serra * It behaves the same as syscon_regmap_lookup_by_phandle() except where
28086b9d170SEnric Balletbo i Serra * there is no regmap phandle. In this case, instead of returning -ENODEV,
28186b9d170SEnric Balletbo i Serra * the function returns NULL.
28286b9d170SEnric Balletbo i Serra */
syscon_regmap_lookup_by_phandle_optional(struct device_node * np,const char * property)28386b9d170SEnric Balletbo i Serra struct regmap *syscon_regmap_lookup_by_phandle_optional(struct device_node *np,
28486b9d170SEnric Balletbo i Serra const char *property)
28586b9d170SEnric Balletbo i Serra {
28686b9d170SEnric Balletbo i Serra struct regmap *regmap;
28786b9d170SEnric Balletbo i Serra
28886b9d170SEnric Balletbo i Serra regmap = syscon_regmap_lookup_by_phandle(np, property);
28986b9d170SEnric Balletbo i Serra if (IS_ERR(regmap) && PTR_ERR(regmap) == -ENODEV)
29086b9d170SEnric Balletbo i Serra return NULL;
29186b9d170SEnric Balletbo i Serra
29286b9d170SEnric Balletbo i Serra return regmap;
29386b9d170SEnric Balletbo i Serra }
29486b9d170SEnric Balletbo i Serra EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle_optional);
29586b9d170SEnric Balletbo i Serra
syscon_probe(struct platform_device * pdev)296f791be49SBill Pemberton static int syscon_probe(struct platform_device *pdev)
29787d68730SDong Aisheng {
29887d68730SDong Aisheng struct device *dev = &pdev->dev;
29929f9b6cfSPawel Moll struct syscon_platform_data *pdata = dev_get_platdata(dev);
30087d68730SDong Aisheng struct syscon *syscon;
301c131045dSPhilipp Zabel struct regmap_config syscon_config = syscon_regmap_config;
3025ab3a89aSAlexander Shiyan struct resource *res;
303f10111ccSAlexander Shiyan void __iomem *base;
30487d68730SDong Aisheng
3055ab3a89aSAlexander Shiyan syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
30687d68730SDong Aisheng if (!syscon)
30787d68730SDong Aisheng return -ENOMEM;
30887d68730SDong Aisheng
3095ab3a89aSAlexander Shiyan res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
3105ab3a89aSAlexander Shiyan if (!res)
3115ab3a89aSAlexander Shiyan return -ENOENT;
3125ab3a89aSAlexander Shiyan
313f10111ccSAlexander Shiyan base = devm_ioremap(dev, res->start, resource_size(res));
314f10111ccSAlexander Shiyan if (!base)
3155ab3a89aSAlexander Shiyan return -ENOMEM;
31687d68730SDong Aisheng
317f2a19c5bSAndy Shevchenko syscon_config.max_register = resource_size(res) - 4;
31829f9b6cfSPawel Moll if (pdata)
319c131045dSPhilipp Zabel syscon_config.name = pdata->label;
320c131045dSPhilipp Zabel syscon->regmap = devm_regmap_init_mmio(dev, base, &syscon_config);
32187d68730SDong Aisheng if (IS_ERR(syscon->regmap)) {
32287d68730SDong Aisheng dev_err(dev, "regmap init failed\n");
32387d68730SDong Aisheng return PTR_ERR(syscon->regmap);
32487d68730SDong Aisheng }
32587d68730SDong Aisheng
32687d68730SDong Aisheng platform_set_drvdata(pdev, syscon);
32787d68730SDong Aisheng
32838d8974eSAlexander Shiyan dev_dbg(dev, "regmap %pR registered\n", res);
32987d68730SDong Aisheng
33087d68730SDong Aisheng return 0;
33187d68730SDong Aisheng }
33287d68730SDong Aisheng
3335ab3a89aSAlexander Shiyan static const struct platform_device_id syscon_ids[] = {
3345ab3a89aSAlexander Shiyan { "syscon", },
3355ab3a89aSAlexander Shiyan { }
3365ab3a89aSAlexander Shiyan };
33787d68730SDong Aisheng
33887d68730SDong Aisheng static struct platform_driver syscon_driver = {
33987d68730SDong Aisheng .driver = {
34087d68730SDong Aisheng .name = "syscon",
34187d68730SDong Aisheng },
34287d68730SDong Aisheng .probe = syscon_probe,
3435ab3a89aSAlexander Shiyan .id_table = syscon_ids,
34487d68730SDong Aisheng };
34587d68730SDong Aisheng
syscon_init(void)34687d68730SDong Aisheng static int __init syscon_init(void)
34787d68730SDong Aisheng {
34887d68730SDong Aisheng return platform_driver_register(&syscon_driver);
34987d68730SDong Aisheng }
35087d68730SDong Aisheng postcore_initcall(syscon_init);
351