// SPDX-License-Identifier: GPL-2.0+ /* * Watchdog device driver for DA9062 and DA9061 PMICs * Copyright (C) 2015 Dialog Semiconductor Ltd. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 }; #define DA9062_TWDSCALE_DISABLE 0 #define DA9062_TWDSCALE_MIN 1 #define DA9062_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1) #define DA9062_WDT_MIN_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MIN] #define DA9062_WDT_MAX_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX] #define DA9062_WDG_DEFAULT_TIMEOUT wdt_timeout[DA9062_TWDSCALE_MAX-1] #define DA9062_RESET_PROTECTION_MS 300 struct da9062_watchdog { struct da9062 *hw; struct watchdog_device wdtdev; bool use_sw_pm; }; static unsigned int da9062_wdt_read_timeout(struct da9062_watchdog *wdt) { unsigned int val; regmap_read(wdt->hw->regmap, DA9062AA_CONTROL_D, &val); return wdt_timeout[val & DA9062AA_TWDSCALE_MASK]; } static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs) { unsigned int i; for (i = DA9062_TWDSCALE_MIN; i <= DA9062_TWDSCALE_MAX; i++) { if (wdt_timeout[i] >= secs) return i; } return DA9062_TWDSCALE_MAX; } static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt) { return regmap_update_bits(wdt->hw->regmap, DA9062AA_CONTROL_F, DA9062AA_WATCHDOG_MASK, DA9062AA_WATCHDOG_MASK); } static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt, unsigned int regval) { struct da9062 *chip = wdt->hw; regmap_update_bits(chip->regmap, DA9062AA_CONTROL_D, DA9062AA_TWDSCALE_MASK, DA9062_TWDSCALE_DISABLE); usleep_range(150, 300); return regmap_update_bits(chip->regmap, DA9062AA_CONTROL_D, DA9062AA_TWDSCALE_MASK, regval); } static int da9062_wdt_start(struct watchdog_device *wdd) { struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); unsigned int selector; int ret; selector = da9062_wdt_timeout_to_sel(wdt->wdtdev.timeout); ret = da9062_wdt_update_timeout_register(wdt, selector); if (ret) dev_err(wdt->hw->dev, "Watchdog failed to start (err = %d)\n", ret); return ret; } static int da9062_wdt_stop(struct watchdog_device *wdd) { struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); int ret; ret = regmap_update_bits(wdt->hw->regmap, DA9062AA_CONTROL_D, DA9062AA_TWDSCALE_MASK, DA9062_TWDSCALE_DISABLE); if (ret) dev_err(wdt->hw->dev, "Watchdog failed to stop (err = %d)\n", ret); return ret; } static int da9062_wdt_ping(struct watchdog_device *wdd) { struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); int ret; ret = da9062_reset_watchdog_timer(wdt); if (ret) dev_err(wdt->hw->dev, "Failed to ping the watchdog (err = %d)\n", ret); return ret; } static int da9062_wdt_set_timeout(struct watchdog_device *wdd, unsigned int timeout) { struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); unsigned int selector; int ret; selector = da9062_wdt_timeout_to_sel(timeout); ret = da9062_wdt_update_timeout_register(wdt, selector); if (ret) dev_err(wdt->hw->dev, "Failed to set watchdog timeout (err = %d)\n", ret); else wdd->timeout = wdt_timeout[selector]; return ret; } static int da9062_wdt_restart(struct watchdog_device *wdd, unsigned long action, void *data) { struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); struct i2c_client *client = to_i2c_client(wdt->hw->dev); int ret; /* Don't use regmap because it is not atomic safe */ ret = i2c_smbus_write_byte_data(client, DA9062AA_CONTROL_F, DA9062AA_SHUTDOWN_MASK); if (ret < 0) dev_alert(wdt->hw->dev, "Failed to shutdown (err = %d)\n", ret); /* wait for reset to assert... */ mdelay(500); return ret; } static const struct watchdog_info da9062_watchdog_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, .identity = "DA9062 WDT", }; static const struct watchdog_ops da9062_watchdog_ops = { .owner = THIS_MODULE, .start = da9062_wdt_start, .stop = da9062_wdt_stop, .ping = da9062_wdt_ping, .set_timeout = da9062_wdt_set_timeout, .restart = da9062_wdt_restart, }; static const struct of_device_id da9062_compatible_id_table[] = { { .compatible = "dlg,da9062-watchdog", }, { }, }; MODULE_DEVICE_TABLE(of, da9062_compatible_id_table); static int da9062_wdt_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; unsigned int timeout; struct da9062 *chip; struct da9062_watchdog *wdt; chip = dev_get_drvdata(dev->parent); if (!chip) return -EINVAL; wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL); if (!wdt) return -ENOMEM; wdt->use_sw_pm = device_property_present(dev, "dlg,use-sw-pm"); wdt->hw = chip; wdt->wdtdev.info = &da9062_watchdog_info; wdt->wdtdev.ops = &da9062_watchdog_ops; wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT; wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT; wdt->wdtdev.min_hw_heartbeat_ms = DA9062_RESET_PROTECTION_MS; wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT; wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS; wdt->wdtdev.parent = dev; watchdog_set_restart_priority(&wdt->wdtdev, 128); watchdog_set_drvdata(&wdt->wdtdev, wdt); dev_set_drvdata(dev, &wdt->wdtdev); timeout = da9062_wdt_read_timeout(wdt); if (timeout) wdt->wdtdev.timeout = timeout; /* Set timeout from DT value if available */ watchdog_init_timeout(&wdt->wdtdev, 0, dev); if (timeout) { da9062_wdt_set_timeout(&wdt->wdtdev, wdt->wdtdev.timeout); set_bit(WDOG_HW_RUNNING, &wdt->wdtdev.status); } return devm_watchdog_register_device(dev, &wdt->wdtdev); } static int __maybe_unused da9062_wdt_suspend(struct device *dev) { struct watchdog_device *wdd = dev_get_drvdata(dev); struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); if (!wdt->use_sw_pm) return 0; if (watchdog_active(wdd)) return da9062_wdt_stop(wdd); return 0; } static int __maybe_unused da9062_wdt_resume(struct device *dev) { struct watchdog_device *wdd = dev_get_drvdata(dev); struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd); if (!wdt->use_sw_pm) return 0; if (watchdog_active(wdd)) return da9062_wdt_start(wdd); return 0; } static SIMPLE_DEV_PM_OPS(da9062_wdt_pm_ops, da9062_wdt_suspend, da9062_wdt_resume); static struct platform_driver da9062_wdt_driver = { .probe = da9062_wdt_probe, .driver = { .name = "da9062-watchdog", .pm = &da9062_wdt_pm_ops, .of_match_table = da9062_compatible_id_table, }, }; module_platform_driver(da9062_wdt_driver); MODULE_AUTHOR("S Twiss "); MODULE_DESCRIPTION("WDT device driver for Dialog DA9062 and DA9061"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:da9062-watchdog");