This patch adds a driver for the Zodiac Aerospace RAVE Watchdog Procesor. This device implements a watchdog timer, accessible over I2C. Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Signed-off-by: Martyn Welch <martyn.welch@xxxxxxxxxxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- v2: - Improved error handling. - Correct indentation of split lines. - Remove unnecessary checks, casts and bracketing. - Remove sysfs entries provided by standard mechanisms. - Remove simple access functions. - Allocate wdd as a part of w_priv. - Add ability to set timeout from module parameter or device tree property rather than through a sysfs entry. - Add ability to set reset duration from module parameter or device tree property rather than through a sysfs entry. v3: - Correct naming of reset-duration-msec -> reset-duration-ms - Improved timeout logic (wasn't falling back to default, whoops.) v4: - Correct number of entries in ziirave_reasons array. - Remove unused defines and arrays. - Merge revision functions. - Remove unneeded range check. - Remove unneeded variables & initialisations. - Remove unused flags from i2c_check_functionality(). - Move more initialisation before registration. - Check returned timeout value. v5: - Correct missed bad indentation & error checking. - Treat lack of DT/module param for duration differently from a failure to set or bad value. - Reorder includes. v6: - Remove trailing blank line. - Correct comment subject. drivers/watchdog/Kconfig | 11 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/ziirave_wdt.c | 381 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 393 insertions(+) create mode 100644 drivers/watchdog/ziirave_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 7a8a6c6..816b5fb 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -161,6 +161,17 @@ config XILINX_WATCHDOG To compile this driver as a module, choose M here: the module will be called of_xilinx_wdt. +config ZIIRAVE_WATCHDOG + tristate "Zodiac RAVE Watchdog Timer" + depends on I2C + select WATCHDOG_CORE + help + Watchdog driver for the Zodiac Aerospace RAVE Switch Watchdog + Processor. + + To compile this driver as a module, choose M here: the + module will be called ziirave_wdt. + # ALPHA Architecture # ARM Architecture diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index 53d4827..05ba23a 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -190,5 +190,6 @@ obj-$(CONFIG_GPIO_WATCHDOG) += gpio_wdt.o obj-$(CONFIG_WM831X_WATCHDOG) += wm831x_wdt.o obj-$(CONFIG_WM8350_WATCHDOG) += wm8350_wdt.o obj-$(CONFIG_MAX63XX_WATCHDOG) += max63xx_wdt.o +obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o diff --git a/drivers/watchdog/ziirave_wdt.c b/drivers/watchdog/ziirave_wdt.c new file mode 100644 index 0000000..b498fdc --- /dev/null +++ b/drivers/watchdog/ziirave_wdt.c @@ -0,0 +1,381 @@ +/* + * Copyright (C) 2015 Zodiac Inflight Innovations + * + * Author: Martyn Welch <martyn.welch@xxxxxxxxxxxxxxx> + * + * Based on twl4030_wdt.c by Timo Kokkonen <timo.t.kokkonen at nokia.com>: + * + * Copyright (C) Nokia Corporation + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/sysfs.h> +#include <linux/types.h> +#include <linux/version.h> +#include <linux/watchdog.h> + +#define ZIIRAVE_TIMEOUT_MIN 3 +#define ZIIRAVE_TIMEOUT_MAX 255 + +#define ZIIRAVE_PING_VALUE 0x0 + +#define ZIIRAVE_STATE_INITIAL 0x0 +#define ZIIRAVE_STATE_OFF 0x1 +#define ZIIRAVE_STATE_ON 0x2 + +static char *ziirave_reasons[] = {"power cycle", "triggered", NULL, NULL, + "host request", NULL, "illegal configuration", + "illegal instruction", "illegal trap", + "unknown"}; + +#define ZIIRAVE_WDT_FIRM_VER_MAJOR 0x1 +#define ZIIRAVE_WDT_BOOT_VER_MAJOR 0x3 +#define ZIIRAVE_WDT_RESET_REASON 0x5 +#define ZIIRAVE_WDT_STATE 0x6 +#define ZIIRAVE_WDT_TIMEOUT 0x7 +#define ZIIRAVE_WDT_TIME_LEFT 0x8 +#define ZIIRAVE_WDT_PING 0x9 +#define ZIIRAVE_WDT_RESET_DURATION 0xa + +struct ziirave_wdt_rev { + unsigned char major; + unsigned char minor; +}; + +struct ziirave_wdt_data { + struct watchdog_device wdd; + struct ziirave_wdt_rev bootloader_rev; + struct ziirave_wdt_rev firmware_rev; + int reset_reason; +}; + +static int wdt_timeout; +module_param(wdt_timeout, int, 0); +MODULE_PARM_DESC(wdt_timeout, "Watchdog timeout in seconds"); + +static int reset_duration; +module_param(reset_duration, int, 0); +MODULE_PARM_DESC(reset_duration, + "Watchdog reset pulse duration in milliseconds"); + +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started default=" + __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +static int ziirave_wdt_revision(struct i2c_client *client, + struct ziirave_wdt_rev *rev, u8 command) +{ + int ret; + + ret = i2c_smbus_read_byte_data(client, command); + if (ret < 0) + return ret; + + rev->major = ret; + + ret = i2c_smbus_read_byte_data(client, command + 1); + if (ret < 0) + return ret; + + rev->minor = ret; + + return 0; +} + +static int ziirave_wdt_set_state(struct watchdog_device *wdd, int state) +{ + struct i2c_client *client = to_i2c_client(wdd->parent); + + return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_STATE, state); +} + +static int ziirave_wdt_start(struct watchdog_device *wdd) +{ + return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_ON); +} + +static int ziirave_wdt_stop(struct watchdog_device *wdd) +{ + return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_OFF); +} + +static int ziirave_wdt_ping(struct watchdog_device *wdd) +{ + struct i2c_client *client = to_i2c_client(wdd->parent); + + return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_PING, + ZIIRAVE_PING_VALUE); +} + +static int ziirave_wdt_set_timeout(struct watchdog_device *wdd, + unsigned int timeout) +{ + struct i2c_client *client = to_i2c_client(wdd->parent); + int ret; + + ret = i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_TIMEOUT, timeout); + if (!ret) + wdd->timeout = timeout; + + return ret; +} + +static unsigned int ziirave_wdt_get_timeleft(struct watchdog_device *wdd) +{ + struct i2c_client *client = to_i2c_client(wdd->parent); + int ret; + + ret = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIME_LEFT); + if (ret < 0) + ret = 0; + + return ret; +} + +static const struct watchdog_info ziirave_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, + .identity = "Zodiac RAVE Watchdog", +}; + +static const struct watchdog_ops ziirave_wdt_ops = { + .owner = THIS_MODULE, + .start = ziirave_wdt_start, + .stop = ziirave_wdt_stop, + .ping = ziirave_wdt_ping, + .set_timeout = ziirave_wdt_set_timeout, + .get_timeleft = ziirave_wdt_get_timeleft, +}; + +static ssize_t ziirave_wdt_sysfs_show_firm(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev->parent); + struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client); + + return sprintf(buf, "02.%02u.%02u", w_priv->firmware_rev.major, + w_priv->firmware_rev.minor); +} + +static DEVICE_ATTR(firmware_version, S_IRUGO, ziirave_wdt_sysfs_show_firm, + NULL); + +static ssize_t ziirave_wdt_sysfs_show_boot(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev->parent); + struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client); + + return sprintf(buf, "01.%02u.%02u", w_priv->bootloader_rev.major, + w_priv->bootloader_rev.minor); +} + +static DEVICE_ATTR(bootloader_version, S_IRUGO, ziirave_wdt_sysfs_show_boot, + NULL); + +static ssize_t ziirave_wdt_sysfs_show_reason(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct i2c_client *client = to_i2c_client(dev->parent); + struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client); + + return sprintf(buf, "%s", ziirave_reasons[w_priv->reset_reason]); +} + +static DEVICE_ATTR(reset_reason, S_IRUGO, ziirave_wdt_sysfs_show_reason, + NULL); + +static struct attribute *ziirave_wdt_attrs[] = { + &dev_attr_firmware_version.attr, + &dev_attr_bootloader_version.attr, + &dev_attr_reset_reason.attr, + NULL +}; + +static const struct attribute_group ziirave_wdt_sysfs_files = { + .attrs = ziirave_wdt_attrs, +}; + +static int ziirave_wdt_init_duration(struct i2c_client *client) +{ + int ret; + + if (!reset_duration) { + /* See if the reset pulse duration is provided in an of_node */ + if (!client->dev.of_node) + ret = -ENODEV; + else + ret = of_property_read_u32(client->dev.of_node, + "reset-duration-ms", + &reset_duration); + if (ret) { + dev_info(&client->dev, + "Unable to set reset pulse duration, using default\n"); + return 0; + } + } + + if (reset_duration < 1 || reset_duration > 255) + return -EINVAL; + + dev_info(&client->dev, "Setting reset duration to %dms", + reset_duration); + + return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_RESET_DURATION, + reset_duration); +} + +static int ziirave_wdt_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + int ret; + struct ziirave_wdt_data *w_priv; + int val; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA)) + return -ENODEV; + + w_priv = devm_kzalloc(&client->dev, sizeof(*w_priv), GFP_KERNEL); + if (!w_priv) + return -ENOMEM; + + w_priv->wdd.info = &ziirave_wdt_info; + w_priv->wdd.ops = &ziirave_wdt_ops; + w_priv->wdd.min_timeout = ZIIRAVE_TIMEOUT_MIN; + w_priv->wdd.max_timeout = ZIIRAVE_TIMEOUT_MAX; + w_priv->wdd.parent = &client->dev; + + ret = watchdog_init_timeout(&w_priv->wdd, wdt_timeout, &client->dev); + if (ret) { + dev_info(&client->dev, + "Unable to select timeout value, using default\n"); + } + + /* + * The default value set in the watchdog should be perfectly valid, so + * pass that in if we haven't provided one via the module parameter or + * of property. + */ + if (w_priv->wdd.timeout == 0) { + val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIMEOUT); + if (val < 0) + return val; + + if (val < ZIIRAVE_TIMEOUT_MIN) + return -ENODEV; + + w_priv->wdd.timeout = val; + } else { + ret = ziirave_wdt_set_timeout(&w_priv->wdd, + w_priv->wdd.timeout); + if (ret) + return ret; + + dev_info(&client->dev, "Timeout set to %ds.", + w_priv->wdd.timeout); + } + + watchdog_set_nowayout(&w_priv->wdd, nowayout); + + i2c_set_clientdata(client, w_priv); + + /* If in unconfigured state, set to stopped */ + val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_STATE); + if (val < 0) + return val; + + if (val == ZIIRAVE_STATE_INITIAL) + ziirave_wdt_stop(&w_priv->wdd); + + ret = ziirave_wdt_init_duration(client); + if (ret) + return ret; + + ret = ziirave_wdt_revision(client, &w_priv->firmware_rev, + ZIIRAVE_WDT_FIRM_VER_MAJOR); + if (ret) + return ret; + + ret = ziirave_wdt_revision(client, &w_priv->bootloader_rev, + ZIIRAVE_WDT_BOOT_VER_MAJOR); + if (ret) + return ret; + + w_priv->reset_reason = i2c_smbus_read_byte_data(client, + ZIIRAVE_WDT_RESET_REASON); + if (w_priv->reset_reason < 0) + return w_priv->reset_reason; + + if (w_priv->reset_reason >= ARRAY_SIZE(ziirave_reasons) || + !ziirave_reasons[w_priv->reset_reason]) + return -ENODEV; + + ret = watchdog_register_device(&w_priv->wdd); + if (ret) + return ret; + + ret = sysfs_create_group(&w_priv->wdd.dev->kobj, + &ziirave_wdt_sysfs_files); + if (ret) { + watchdog_unregister_device(&w_priv->wdd); + + return ret; + } + + return 0; +} + +static int ziirave_wdt_remove(struct i2c_client *client) +{ + struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client); + + sysfs_remove_group(&client->dev.kobj, &ziirave_wdt_sysfs_files); + + watchdog_unregister_device(&w_priv->wdd); + + return 0; +} + +static struct i2c_device_id ziirave_wdt_id[] = { + { "ziirave-wdt", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ziirave_wdt_id); + +static const struct of_device_id zrv_wdt_of_match[] = { + { .compatible = "zii,rave-wdt", }, + { }, +}; +MODULE_DEVICE_TABLE(of, zrv_wdt_of_match); + +static struct i2c_driver ziirave_wdt_driver = { + .driver = { + .name = "ziirave_wdt", + .of_match_table = zrv_wdt_of_match, + }, + .probe = ziirave_wdt_probe, + .remove = ziirave_wdt_remove, + .id_table = ziirave_wdt_id, +}; + +module_i2c_driver(ziirave_wdt_driver); + +MODULE_AUTHOR("Martyn Welch <martyn.welch@xxxxxxxxxxxxxxx"); +MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver"); +MODULE_LICENSE("GPL"); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html