diff options
Diffstat (limited to 'drivers/watchdog/ts72xx_wdt.c')
| -rw-r--r-- | drivers/watchdog/ts72xx_wdt.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/drivers/watchdog/ts72xx_wdt.c b/drivers/watchdog/ts72xx_wdt.c new file mode 100644 index 000000000..bf918f5fa --- /dev/null +++ b/drivers/watchdog/ts72xx_wdt.c @@ -0,0 +1,177 @@ +/* + * Watchdog driver for Technologic Systems TS-72xx based SBCs + * (TS-7200, TS-7250 and TS-7260). These boards have external + * glue logic CPLD chip, which includes programmable watchdog + * timer. + * + * Copyright (c) 2009 Mika Westerberg <mika.westerberg@iki.fi> + * + * This driver is based on ep93xx_wdt and wm831x_wdt drivers. + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/platform_device.h> +#include <linux/module.h> +#include <linux/watchdog.h> +#include <linux/io.h> + +#define TS72XX_WDT_DEFAULT_TIMEOUT 30 + +static int timeout; +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds."); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); + +/* priv->control_reg */ +#define TS72XX_WDT_CTRL_DISABLE 0x00 +#define TS72XX_WDT_CTRL_250MS 0x01 +#define TS72XX_WDT_CTRL_500MS 0x02 +#define TS72XX_WDT_CTRL_1SEC 0x03 +#define TS72XX_WDT_CTRL_RESERVED 0x04 +#define TS72XX_WDT_CTRL_2SEC 0x05 +#define TS72XX_WDT_CTRL_4SEC 0x06 +#define TS72XX_WDT_CTRL_8SEC 0x07 + +/* priv->feed_reg */ +#define TS72XX_WDT_FEED_VAL 0x05 + +struct ts72xx_wdt_priv { + void __iomem *control_reg; + void __iomem *feed_reg; + struct watchdog_device wdd; + unsigned char regval; +}; + +static int ts72xx_wdt_start(struct watchdog_device *wdd) +{ + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); + + writeb(TS72XX_WDT_FEED_VAL, priv->feed_reg); + writeb(priv->regval, priv->control_reg); + + return 0; +} + +static int ts72xx_wdt_stop(struct watchdog_device *wdd) +{ + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); + + writeb(TS72XX_WDT_FEED_VAL, priv->feed_reg); + writeb(TS72XX_WDT_CTRL_DISABLE, priv->control_reg); + + return 0; +} + +static int ts72xx_wdt_ping(struct watchdog_device *wdd) +{ + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); + + writeb(TS72XX_WDT_FEED_VAL, priv->feed_reg); + + return 0; +} + +static int ts72xx_wdt_settimeout(struct watchdog_device *wdd, unsigned int to) +{ + struct ts72xx_wdt_priv *priv = watchdog_get_drvdata(wdd); + + if (to == 1) { + priv->regval = TS72XX_WDT_CTRL_1SEC; + } else if (to == 2) { + priv->regval = TS72XX_WDT_CTRL_2SEC; + } else if (to <= 4) { + priv->regval = TS72XX_WDT_CTRL_4SEC; + to = 4; + } else { + priv->regval = TS72XX_WDT_CTRL_8SEC; + if (to <= 8) + to = 8; + } + + wdd->timeout = to; + + if (watchdog_active(wdd)) { + ts72xx_wdt_stop(wdd); + ts72xx_wdt_start(wdd); + } + + return 0; +} + +static const struct watchdog_info ts72xx_wdt_ident = { + .options = WDIOF_KEEPALIVEPING | + WDIOF_SETTIMEOUT | + WDIOF_MAGICCLOSE, + .firmware_version = 1, + .identity = "TS-72XX WDT", +}; + +static const struct watchdog_ops ts72xx_wdt_ops = { + .owner = THIS_MODULE, + .start = ts72xx_wdt_start, + .stop = ts72xx_wdt_stop, + .ping = ts72xx_wdt_ping, + .set_timeout = ts72xx_wdt_settimeout, +}; + +static int ts72xx_wdt_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct ts72xx_wdt_priv *priv; + struct watchdog_device *wdd; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->control_reg = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->control_reg)) + return PTR_ERR(priv->control_reg); + + priv->feed_reg = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(priv->feed_reg)) + return PTR_ERR(priv->feed_reg); + + wdd = &priv->wdd; + wdd->info = &ts72xx_wdt_ident; + wdd->ops = &ts72xx_wdt_ops; + wdd->min_timeout = 1; + wdd->max_hw_heartbeat_ms = 8000; + wdd->parent = dev; + + watchdog_set_nowayout(wdd, nowayout); + + wdd->timeout = TS72XX_WDT_DEFAULT_TIMEOUT; + watchdog_init_timeout(wdd, timeout, dev); + + watchdog_set_drvdata(wdd, priv); + + ret = devm_watchdog_register_device(dev, wdd); + if (ret) + return ret; + + dev_info(dev, "TS-72xx Watchdog driver\n"); + + return 0; +} + +static struct platform_driver ts72xx_wdt_driver = { + .probe = ts72xx_wdt_probe, + .driver = { + .name = "ts72xx-wdt", + }, +}; + +module_platform_driver(ts72xx_wdt_driver); + +MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>"); +MODULE_DESCRIPTION("TS-72xx SBC Watchdog"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:ts72xx-wdt"); |