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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 | /* * System Control Driver * * Copyright (C) 2012 Freescale Semiconductor, Inc. * Copyright (C) 2012 Linaro Ltd. * * Author: Dong Aisheng <dong.aisheng@linaro.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ #include <linux/err.h> #include <linux/io.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_address.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/regmap.h> static struct platform_driver syscon_driver; struct syscon { struct device *dev; void __iomem *base; struct regmap *regmap; }; static int syscon_match(struct device *dev, void *data) { struct syscon *syscon = dev_get_drvdata(dev); struct device_node *dn = data; return (syscon->dev->of_node == dn) ? 1 : 0; } struct regmap *syscon_node_to_regmap(struct device_node *np) { struct syscon *syscon; struct device *dev; dev = driver_find_device(&syscon_driver.driver, NULL, np, syscon_match); if (!dev) return ERR_PTR(-EPROBE_DEFER); syscon = dev_get_drvdata(dev); return syscon->regmap; } EXPORT_SYMBOL_GPL(syscon_node_to_regmap); struct regmap *syscon_regmap_lookup_by_compatible(const char *s) { struct device_node *syscon_np; struct regmap *regmap; syscon_np = of_find_compatible_node(NULL, NULL, s); if (!syscon_np) return ERR_PTR(-ENODEV); regmap = syscon_node_to_regmap(syscon_np); of_node_put(syscon_np); return regmap; } EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible); struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np, const char *property) { struct device_node *syscon_np; struct regmap *regmap; syscon_np = of_parse_phandle(np, property, 0); if (!syscon_np) return ERR_PTR(-ENODEV); regmap = syscon_node_to_regmap(syscon_np); of_node_put(syscon_np); return regmap; } EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle); static const struct of_device_id of_syscon_match[] = { { .compatible = "syscon", }, { }, }; static struct regmap_config syscon_regmap_config = { .reg_bits = 32, .val_bits = 32, .reg_stride = 4, }; static int syscon_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *np = dev->of_node; struct syscon *syscon; struct resource res; int ret; if (!np) return -ENOENT; syscon = devm_kzalloc(dev, sizeof(struct syscon), GFP_KERNEL); if (!syscon) return -ENOMEM; syscon->base = of_iomap(np, 0); if (!syscon->base) return -EADDRNOTAVAIL; ret = of_address_to_resource(np, 0, &res); if (ret) return ret; syscon_regmap_config.max_register = res.end - res.start - 3; syscon->regmap = devm_regmap_init_mmio(dev, syscon->base, &syscon_regmap_config); if (IS_ERR(syscon->regmap)) { dev_err(dev, "regmap init failed\n"); return PTR_ERR(syscon->regmap); } syscon->dev = dev; platform_set_drvdata(pdev, syscon); dev_info(dev, "syscon regmap start 0x%x end 0x%x registered\n", res.start, res.end); return 0; } static int syscon_remove(struct platform_device *pdev) { struct syscon *syscon; syscon = platform_get_drvdata(pdev); iounmap(syscon->base); platform_set_drvdata(pdev, NULL); return 0; } static struct platform_driver syscon_driver = { .driver = { .name = "syscon", .owner = THIS_MODULE, .of_match_table = of_syscon_match, }, .probe = syscon_probe, .remove = syscon_remove, }; static int __init syscon_init(void) { return platform_driver_register(&syscon_driver); } postcore_initcall(syscon_init); static void __exit syscon_exit(void) { platform_driver_unregister(&syscon_driver); } module_exit(syscon_exit); MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>"); MODULE_DESCRIPTION("System Control driver"); MODULE_LICENSE("GPL v2"); |