Loading...
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 | /* * Watchdog driver for DA9063 PMICs. * * Copyright(c) 2012 Dialog Semiconductor Ltd. * * Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.com> * * 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/kernel.h> #include <linux/module.h> #include <linux/watchdog.h> #include <linux/platform_device.h> #include <linux/uaccess.h> #include <linux/slab.h> #include <linux/delay.h> #include <linux/mfd/da9063/registers.h> #include <linux/mfd/da9063/core.h> #include <linux/regmap.h> /* * Watchdog selector to timeout in seconds. * 0: WDT disabled; * others: timeout = 2048 ms * 2^(TWDSCALE-1). */ static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 }; #define DA9063_TWDSCALE_DISABLE 0 #define DA9063_TWDSCALE_MIN 1 #define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1) #define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN] #define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX] #define DA9063_WDG_TIMEOUT wdt_timeout[3] #define DA9063_RESET_PROTECTION_MS 256 static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs) { unsigned int i; for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) { if (wdt_timeout[i] >= secs) return i; } return DA9063_TWDSCALE_MAX; } static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval) { return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D, DA9063_TWDSCALE_MASK, regval); } static int da9063_wdt_start(struct watchdog_device *wdd) { struct da9063 *da9063 = watchdog_get_drvdata(wdd); unsigned int selector; int ret; selector = da9063_wdt_timeout_to_sel(wdd->timeout); ret = _da9063_wdt_set_timeout(da9063, selector); if (ret) dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n", ret); return ret; } static int da9063_wdt_stop(struct watchdog_device *wdd) { struct da9063 *da9063 = watchdog_get_drvdata(wdd); int ret; ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D, DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE); if (ret) dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n", ret); return ret; } static int da9063_wdt_ping(struct watchdog_device *wdd) { struct da9063 *da9063 = watchdog_get_drvdata(wdd); int ret; ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F, DA9063_WATCHDOG); if (ret) dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n", ret); return ret; } static int da9063_wdt_set_timeout(struct watchdog_device *wdd, unsigned int timeout) { struct da9063 *da9063 = watchdog_get_drvdata(wdd); unsigned int selector; int ret = 0; selector = da9063_wdt_timeout_to_sel(timeout); /* * There are two cases when a set_timeout() will be called: * 1. The watchdog is off and someone wants to set the timeout for the * further use. * 2. The watchdog is already running and a new timeout value should be * set. * * The watchdog can't store a timeout value not equal zero without * enabling the watchdog, so the timeout must be buffered by the driver. */ if (watchdog_active(wdd)) ret = _da9063_wdt_set_timeout(da9063, selector); if (ret) dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n", ret); else wdd->timeout = wdt_timeout[selector]; return ret; } static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action, void *data) { struct da9063 *da9063 = watchdog_get_drvdata(wdd); int ret; ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F, DA9063_SHUTDOWN); if (ret) dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n", ret); return ret; } static const struct watchdog_info da9063_watchdog_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, .identity = "DA9063 Watchdog", }; static const struct watchdog_ops da9063_watchdog_ops = { .owner = THIS_MODULE, .start = da9063_wdt_start, .stop = da9063_wdt_stop, .ping = da9063_wdt_ping, .set_timeout = da9063_wdt_set_timeout, .restart = da9063_wdt_restart, }; static int da9063_wdt_probe(struct platform_device *pdev) { struct da9063 *da9063; struct watchdog_device *wdd; if (!pdev->dev.parent) return -EINVAL; da9063 = dev_get_drvdata(pdev->dev.parent); if (!da9063) return -EINVAL; wdd = devm_kzalloc(&pdev->dev, sizeof(*wdd), GFP_KERNEL); if (!wdd) return -ENOMEM; wdd->info = &da9063_watchdog_info; wdd->ops = &da9063_watchdog_ops; wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT; wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT; wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS; wdd->timeout = DA9063_WDG_TIMEOUT; wdd->parent = &pdev->dev; wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS; watchdog_set_restart_priority(wdd, 128); watchdog_set_drvdata(wdd, da9063); return devm_watchdog_register_device(&pdev->dev, wdd); } static struct platform_driver da9063_wdt_driver = { .probe = da9063_wdt_probe, .driver = { .name = DA9063_DRVNAME_WATCHDOG, }, }; module_platform_driver(da9063_wdt_driver); MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>"); MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG); |