watchdog: nic7018_wdt: Add NIC7018 watchdog driver

Add support for the watchdog timer on PXI Embedded Controller.

Signed-off-by: Hui Chun Ong <hui.chun.ong@ni.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt
index e21850e..4f7d86d 100644 (file)
--- a/Documentation/watchdog/watchdog-parameters.txt
+++ b/Documentation/watchdog/watchdog-parameters.txt
@@ -209,6 +209,11 @@ timeout: Initial watchdog timeout in seconds (0<timeout<516, default=60)
 nowayout: Watchdog cannot be stopped once started
        (default=kernel config parameter)
 -------------------------------------------------
+nic7018_wdt:
+timeout: Initial watchdog timeout in seconds (0<timeout<464, default=80)
+nowayout: Watchdog cannot be stopped once started
+       (default=kernel config parameter)
+-------------------------------------------------
 nuc900_wdt:
 heartbeat: Watchdog heartbeats in seconds.
        (default = 15)

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index acb00b5..e20eb42 100644 (file)
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -1326,6 +1326,16 @@ config NI903X_WDT
          To compile this driver as a module, choose M here: the module will be
          called ni903x_wdt.
 
+config NIC7018_WDT
+       tristate "NIC7018 Watchdog"
+       depends on X86 && ACPI
+       select WATCHDOG_CORE
+       ---help---
+         Support for National Instruments NIC7018 Watchdog.
+
+         To compile this driver as a module, choose M here: the module will be
+         called nic7018_wdt.
+
 # M32R Architecture
 
 # M68K Architecture

diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 0c3d35e..3af3588 100644 (file)
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -139,6 +139,7 @@ obj-$(CONFIG_INTEL_SCU_WATCHDOG) += intel_scu_watchdog.o
 obj-$(CONFIG_INTEL_MID_WATCHDOG) += intel-mid_wdt.o
 obj-$(CONFIG_INTEL_MEI_WDT) += mei_wdt.o
 obj-$(CONFIG_NI903X_WDT) += ni903x_wdt.o
+obj-$(CONFIG_NIC7018_WDT) += nic7018_wdt.o
 
 # M32R Architecture
 

diff --git a/drivers/watchdog/nic7018_wdt.c b/drivers/watchdog/nic7018_wdt.c
new file mode 100644 (file)
index 0000000..dcd2656
--- /dev/null
+++ b/drivers/watchdog/nic7018_wdt.c
@@ -0,0 +1,265 @@
+/*
+ * Copyright (C) 2016 National Instruments Corp.
+ *
+ * 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/acpi.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define LOCK                   0xA5
+#define UNLOCK                 0x5A
+
+#define WDT_CTRL_RESET_EN      BIT(7)
+#define WDT_RELOAD_PORT_EN     BIT(7)
+
+#define WDT_CTRL               1
+#define WDT_RELOAD_CTRL                2
+#define WDT_PRESET_PRESCALE    4
+#define WDT_REG_LOCK           5
+#define WDT_COUNT              6
+#define WDT_RELOAD_PORT                7
+
+#define WDT_MIN_TIMEOUT                1
+#define WDT_MAX_TIMEOUT                464
+#define WDT_DEFAULT_TIMEOUT    80
+
+#define WDT_MAX_COUNTER                15
+
+static unsigned int timeout;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout,
+                "Watchdog timeout in seconds. (default="
+                __MODULE_STRING(WDT_DEFAULT_TIMEOUT) ")");
+
+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) ")");
+
+struct nic7018_wdt {
+       u16 io_base;
+       u32 period;
+       struct watchdog_device wdd;
+};
+
+struct nic7018_config {
+       u32 period;
+       u8 divider;
+};
+
+static const struct nic7018_config nic7018_configs[] = {
+       {  2, 4 },
+       { 32, 5 },
+};
+
+static inline u32 nic7018_timeout(u32 period, u8 counter)
+{
+       return period * counter - period / 2;
+}
+
+static const struct nic7018_config *nic7018_get_config(u32 timeout,
+                                                      u8 *counter)
+{
+       const struct nic7018_config *config;
+       u8 count;
+
+       if (timeout < 30 && timeout != 16) {
+               config = &nic7018_configs[0];
+               count = timeout / 2 + 1;
+       } else {
+               config = &nic7018_configs[1];
+               count = DIV_ROUND_UP(timeout + 16, 32);
+
+               if (count > WDT_MAX_COUNTER)
+                       count = WDT_MAX_COUNTER;
+       }
+       *counter = count;
+       return config;
+}
+
+static int nic7018_set_timeout(struct watchdog_device *wdd,
+                              unsigned int timeout)
+{
+       struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
+       const struct nic7018_config *config;
+       u8 counter;
+
+       config = nic7018_get_config(timeout, &counter);
+
+       outb(counter << 4 | config->divider,
+            wdt->io_base + WDT_PRESET_PRESCALE);
+
+       wdd->timeout = nic7018_timeout(config->period, counter);
+       wdt->period = config->period;
+
+       return 0;
+}
+
+static int nic7018_start(struct watchdog_device *wdd)
+{
+       struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
+       u8 control;
+
+       nic7018_set_timeout(wdd, wdd->timeout);
+
+       control = inb(wdt->io_base + WDT_RELOAD_CTRL);
+       outb(control | WDT_RELOAD_PORT_EN, wdt->io_base + WDT_RELOAD_CTRL);
+
+       outb(1, wdt->io_base + WDT_RELOAD_PORT);
+
+       control = inb(wdt->io_base + WDT_CTRL);
+       outb(control | WDT_CTRL_RESET_EN, wdt->io_base + WDT_CTRL);
+
+       return 0;
+}
+
+static int nic7018_stop(struct watchdog_device *wdd)
+{
+       struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
+
+       outb(0, wdt->io_base + WDT_CTRL);
+       outb(0, wdt->io_base + WDT_RELOAD_CTRL);
+       outb(0xF0, wdt->io_base + WDT_PRESET_PRESCALE);
+
+       return 0;
+}
+
+static int nic7018_ping(struct watchdog_device *wdd)
+{
+       struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
+
+       outb(1, wdt->io_base + WDT_RELOAD_PORT);
+
+       return 0;
+}
+
+static unsigned int nic7018_get_timeleft(struct watchdog_device *wdd)
+{
+       struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
+       u8 count;
+
+       count = inb(wdt->io_base + WDT_COUNT) & 0xF;
+       if (!count)
+               return 0;
+
+       return nic7018_timeout(wdt->period, count);
+}
+
+static const struct watchdog_info nic7018_wdd_info = {
+       .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+       .identity = "NIC7018 Watchdog",
+};
+
+static const struct watchdog_ops nic7018_wdd_ops = {
+       .owner = THIS_MODULE,
+       .start = nic7018_start,
+       .stop = nic7018_stop,
+       .ping = nic7018_ping,
+       .set_timeout = nic7018_set_timeout,
+       .get_timeleft = nic7018_get_timeleft,
+};
+
+static int nic7018_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct watchdog_device *wdd;
+       struct nic7018_wdt *wdt;
+       struct resource *io_rc;
+       int ret;
+
+       wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
+       if (!wdt)
+               return -ENOMEM;
+
+       platform_set_drvdata(pdev, wdt);
+
+       io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0);
+       if (!io_rc) {
+               dev_err(dev, "missing IO resources\n");
+               return -EINVAL;
+       }
+
+       if (!devm_request_region(dev, io_rc->start, resource_size(io_rc),
+                                KBUILD_MODNAME)) {
+               dev_err(dev, "failed to get IO region\n");
+               return -EBUSY;
+       }
+
+       wdt->io_base = io_rc->start;
+       wdd = &wdt->wdd;
+       wdd->info = &nic7018_wdd_info;
+       wdd->ops = &nic7018_wdd_ops;
+       wdd->min_timeout = WDT_MIN_TIMEOUT;
+       wdd->max_timeout = WDT_MAX_TIMEOUT;
+       wdd->timeout = WDT_DEFAULT_TIMEOUT;
+       wdd->parent = dev;
+
+       watchdog_set_drvdata(wdd, wdt);
+       watchdog_set_nowayout(wdd, nowayout);
+
+       ret = watchdog_init_timeout(wdd, timeout, dev);
+       if (ret)
+               dev_warn(dev, "unable to set timeout value, using default\n");
+
+       /* Unlock WDT register */
+       outb(UNLOCK, wdt->io_base + WDT_REG_LOCK);
+
+       ret = watchdog_register_device(wdd);
+       if (ret) {
+               outb(LOCK, wdt->io_base + WDT_REG_LOCK);
+               dev_err(dev, "failed to register watchdog\n");
+               return ret;
+       }
+
+       dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",
+               wdt->io_base, timeout, nowayout);
+       return 0;
+}
+
+static int nic7018_remove(struct platform_device *pdev)
+{
+       struct nic7018_wdt *wdt = platform_get_drvdata(pdev);
+
+       watchdog_unregister_device(&wdt->wdd);
+
+       /* Lock WDT register */
+       outb(LOCK, wdt->io_base + WDT_REG_LOCK);
+
+       return 0;
+}
+
+static const struct acpi_device_id nic7018_device_ids[] = {
+       {"NIC7018", 0},
+       {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, nic7018_device_ids);
+
+static struct platform_driver watchdog_driver = {
+       .probe = nic7018_probe,
+       .remove = nic7018_remove,
+       .driver = {
+               .name = KBUILD_MODNAME,
+               .acpi_match_table = ACPI_PTR(nic7018_device_ids),
+       },
+};
+
+module_platform_driver(watchdog_driver);
+
+MODULE_DESCRIPTION("National Instruments NIC7018 Watchdog driver");
+MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
+MODULE_LICENSE("GPL");