1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Watchdog driver for DA9063 PMICs. 4 * 5 * Copyright(c) 2012 Dialog Semiconductor Ltd. 6 * 7 * Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.com> 8 * 9 */ 10 11 #include <linux/kernel.h> 12 #include <linux/module.h> 13 #include <linux/watchdog.h> 14 #include <linux/platform_device.h> 15 #include <linux/uaccess.h> 16 #include <linux/slab.h> 17 #include <linux/delay.h> 18 #include <linux/mfd/da9063/registers.h> 19 #include <linux/mfd/da9063/core.h> 20 #include <linux/regmap.h> 21 22 /* 23 * Watchdog selector to timeout in seconds. 24 * 0: WDT disabled; 25 * others: timeout = 2048 ms * 2^(TWDSCALE-1). 26 */ 27 static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 }; 28 #define DA9063_TWDSCALE_DISABLE 0 29 #define DA9063_TWDSCALE_MIN 1 30 #define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1) 31 #define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN] 32 #define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX] 33 #define DA9063_WDG_TIMEOUT wdt_timeout[3] 34 #define DA9063_RESET_PROTECTION_MS 256 35 36 static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs) 37 { 38 unsigned int i; 39 40 for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) { 41 if (wdt_timeout[i] >= secs) 42 return i; 43 } 44 45 return DA9063_TWDSCALE_MAX; 46 } 47 48 static int _da9063_wdt_set_timeout(struct da9063 *da9063, unsigned int regval) 49 { 50 return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D, 51 DA9063_TWDSCALE_MASK, regval); 52 } 53 54 static int da9063_wdt_start(struct watchdog_device *wdd) 55 { 56 struct da9063 *da9063 = watchdog_get_drvdata(wdd); 57 unsigned int selector; 58 int ret; 59 60 selector = da9063_wdt_timeout_to_sel(wdd->timeout); 61 ret = _da9063_wdt_set_timeout(da9063, selector); 62 if (ret) 63 dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n", 64 ret); 65 66 return ret; 67 } 68 69 static int da9063_wdt_stop(struct watchdog_device *wdd) 70 { 71 struct da9063 *da9063 = watchdog_get_drvdata(wdd); 72 int ret; 73 74 ret = regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D, 75 DA9063_TWDSCALE_MASK, DA9063_TWDSCALE_DISABLE); 76 if (ret) 77 dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n", 78 ret); 79 80 return ret; 81 } 82 83 static int da9063_wdt_ping(struct watchdog_device *wdd) 84 { 85 struct da9063 *da9063 = watchdog_get_drvdata(wdd); 86 int ret; 87 88 ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F, 89 DA9063_WATCHDOG); 90 if (ret) 91 dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n", 92 ret); 93 94 return ret; 95 } 96 97 static int da9063_wdt_set_timeout(struct watchdog_device *wdd, 98 unsigned int timeout) 99 { 100 struct da9063 *da9063 = watchdog_get_drvdata(wdd); 101 unsigned int selector; 102 int ret; 103 104 selector = da9063_wdt_timeout_to_sel(timeout); 105 ret = _da9063_wdt_set_timeout(da9063, selector); 106 if (ret) 107 dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n", 108 ret); 109 else 110 wdd->timeout = wdt_timeout[selector]; 111 112 return ret; 113 } 114 115 static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action, 116 void *data) 117 { 118 struct da9063 *da9063 = watchdog_get_drvdata(wdd); 119 int ret; 120 121 ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F, 122 DA9063_SHUTDOWN); 123 if (ret) 124 dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n", 125 ret); 126 127 return ret; 128 } 129 130 static const struct watchdog_info da9063_watchdog_info = { 131 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, 132 .identity = "DA9063 Watchdog", 133 }; 134 135 static const struct watchdog_ops da9063_watchdog_ops = { 136 .owner = THIS_MODULE, 137 .start = da9063_wdt_start, 138 .stop = da9063_wdt_stop, 139 .ping = da9063_wdt_ping, 140 .set_timeout = da9063_wdt_set_timeout, 141 .restart = da9063_wdt_restart, 142 }; 143 144 static int da9063_wdt_probe(struct platform_device *pdev) 145 { 146 struct da9063 *da9063; 147 struct watchdog_device *wdd; 148 149 if (!pdev->dev.parent) 150 return -EINVAL; 151 152 da9063 = dev_get_drvdata(pdev->dev.parent); 153 if (!da9063) 154 return -EINVAL; 155 156 wdd = devm_kzalloc(&pdev->dev, sizeof(*wdd), GFP_KERNEL); 157 if (!wdd) 158 return -ENOMEM; 159 160 wdd->info = &da9063_watchdog_info; 161 wdd->ops = &da9063_watchdog_ops; 162 wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT; 163 wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT; 164 wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS; 165 wdd->timeout = DA9063_WDG_TIMEOUT; 166 wdd->parent = &pdev->dev; 167 168 wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS; 169 170 watchdog_set_restart_priority(wdd, 128); 171 172 watchdog_set_drvdata(wdd, da9063); 173 174 return devm_watchdog_register_device(&pdev->dev, wdd); 175 } 176 177 static struct platform_driver da9063_wdt_driver = { 178 .probe = da9063_wdt_probe, 179 .driver = { 180 .name = DA9063_DRVNAME_WATCHDOG, 181 }, 182 }; 183 module_platform_driver(da9063_wdt_driver); 184 185 MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>"); 186 MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063"); 187 MODULE_LICENSE("GPL"); 188 MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG); 189