summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/ni903x_wdt.c
diff options
context:
space:
mode:
authorKyle Roeschley <kyle.roeschley@ni.com>2016-02-25 11:28:00 -0600
committerWim Van Sebroeck <wim@iguana.be>2016-03-01 16:25:39 +0100
commit70f3997667fb127333862977ba4fd3e855fbf617 (patch)
tree78e0f853571f83539f9620d68cd3bb34eb8b68e7 /drivers/watchdog/ni903x_wdt.c
parent4d8b229d5ea610affe672e919021e9d02cd877da (diff)
downloadlinux-70f3997667fb127333862977ba4fd3e855fbf617.tar.bz2
watchdog: ni903x_wdt: Add NI 903x/913x watchdog driver
Add support for the watchdog timer on NI cRIO-903x and cDAQ-913x real- time controllers. Signed-off-by: Jeff Westfahl <jeff.westfahl@ni.com> Signed-off-by: Kyle Roeschley <kyle.roeschley@ni.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog/ni903x_wdt.c')
-rw-r--r--drivers/watchdog/ni903x_wdt.c270
1 files changed, 270 insertions, 0 deletions
diff --git a/drivers/watchdog/ni903x_wdt.c b/drivers/watchdog/ni903x_wdt.c
new file mode 100644
index 000000000000..dc67742e9018
--- /dev/null
+++ b/drivers/watchdog/ni903x_wdt.c
@@ -0,0 +1,270 @@
+/*
+ * 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/device.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/watchdog.h>
+
+#define NIWD_CONTROL 0x01
+#define NIWD_COUNTER2 0x02
+#define NIWD_COUNTER1 0x03
+#define NIWD_COUNTER0 0x04
+#define NIWD_SEED2 0x05
+#define NIWD_SEED1 0x06
+#define NIWD_SEED0 0x07
+
+#define NIWD_IO_SIZE 0x08
+
+#define NIWD_CONTROL_MODE 0x80
+#define NIWD_CONTROL_PROC_RESET 0x20
+#define NIWD_CONTROL_PET 0x10
+#define NIWD_CONTROL_RUNNING 0x08
+#define NIWD_CONTROL_CAPTURECOUNTER 0x04
+#define NIWD_CONTROL_RESET 0x02
+#define NIWD_CONTROL_ALARM 0x01
+
+#define NIWD_PERIOD_NS 30720
+#define NIWD_MIN_TIMEOUT 1
+#define NIWD_MAX_TIMEOUT 515
+#define NIWD_DEFAULT_TIMEOUT 60
+
+#define NIWD_NAME "ni903x_wdt"
+
+struct ni903x_wdt {
+ struct device *dev;
+ u16 io_base;
+ struct watchdog_device wdd;
+};
+
+static unsigned int timeout;
+module_param(timeout, uint, 0);
+MODULE_PARM_DESC(timeout,
+ "Watchdog timeout in seconds. (default="
+ __MODULE_STRING(NIWD_DEFAULT_TIMEOUT) ")");
+
+static int nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, int, S_IRUGO);
+MODULE_PARM_DESC(nowayout,
+ "Watchdog cannot be stopped once started (default="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
+
+static void ni903x_start(struct ni903x_wdt *wdt)
+{
+ u8 control = inb(wdt->io_base + NIWD_CONTROL);
+
+ outb(control | NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);
+ outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);
+}
+
+static int ni903x_wdd_set_timeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
+ u32 counter = timeout * (1000000000 / NIWD_PERIOD_NS);
+
+ outb(((0x00FF0000 & counter) >> 16), wdt->io_base + NIWD_SEED2);
+ outb(((0x0000FF00 & counter) >> 8), wdt->io_base + NIWD_SEED1);
+ outb((0x000000FF & counter), wdt->io_base + NIWD_SEED0);
+
+ wdd->timeout = timeout;
+
+ return 0;
+}
+
+static unsigned int ni903x_wdd_get_timeleft(struct watchdog_device *wdd)
+{
+ struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
+ u8 control, counter0, counter1, counter2;
+ u32 counter;
+
+ control = inb(wdt->io_base + NIWD_CONTROL);
+ control |= NIWD_CONTROL_CAPTURECOUNTER;
+ outb(control, wdt->io_base + NIWD_CONTROL);
+
+ counter2 = inb(wdt->io_base + NIWD_COUNTER2);
+ counter1 = inb(wdt->io_base + NIWD_COUNTER1);
+ counter0 = inb(wdt->io_base + NIWD_COUNTER0);
+
+ counter = (counter2 << 16) | (counter1 << 8) | counter0;
+
+ return counter / (1000000000 / NIWD_PERIOD_NS);
+}
+
+static int ni903x_wdd_ping(struct watchdog_device *wdd)
+{
+ struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
+ u8 control;
+
+ control = inb(wdt->io_base + NIWD_CONTROL);
+ outb(control | NIWD_CONTROL_PET, wdt->io_base + NIWD_CONTROL);
+
+ return 0;
+}
+
+static int ni903x_wdd_start(struct watchdog_device *wdd)
+{
+ struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
+
+ outb(NIWD_CONTROL_RESET | NIWD_CONTROL_PROC_RESET,
+ wdt->io_base + NIWD_CONTROL);
+
+ ni903x_wdd_set_timeout(wdd, wdd->timeout);
+ ni903x_start(wdt);
+
+ return 0;
+}
+
+static int ni903x_wdd_stop(struct watchdog_device *wdd)
+{
+ struct ni903x_wdt *wdt = watchdog_get_drvdata(wdd);
+
+ outb(NIWD_CONTROL_RESET, wdt->io_base + NIWD_CONTROL);
+
+ return 0;
+}
+
+static acpi_status ni903x_resources(struct acpi_resource *res, void *data)
+{
+ struct ni903x_wdt *wdt = data;
+ u16 io_size;
+
+ switch (res->type) {
+ case ACPI_RESOURCE_TYPE_IO:
+ if (wdt->io_base != 0) {
+ dev_err(wdt->dev, "too many IO resources\n");
+ return AE_ERROR;
+ }
+
+ wdt->io_base = res->data.io.minimum;
+ io_size = res->data.io.address_length;
+
+ if (io_size < NIWD_IO_SIZE) {
+ dev_err(wdt->dev, "memory region too small\n");
+ return AE_ERROR;
+ }
+
+ if (!devm_request_region(wdt->dev, wdt->io_base, io_size,
+ NIWD_NAME)) {
+ dev_err(wdt->dev, "failed to get memory region\n");
+ return AE_ERROR;
+ }
+
+ return AE_OK;
+
+ case ACPI_RESOURCE_TYPE_END_TAG:
+ default:
+ /* Ignore unsupported resources, e.g. IRQ */
+ return AE_OK;
+ }
+}
+
+static const struct watchdog_info ni903x_wdd_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "NI Watchdog",
+};
+
+static const struct watchdog_ops ni903x_wdd_ops = {
+ .owner = THIS_MODULE,
+ .start = ni903x_wdd_start,
+ .stop = ni903x_wdd_stop,
+ .ping = ni903x_wdd_ping,
+ .set_timeout = ni903x_wdd_set_timeout,
+ .get_timeleft = ni903x_wdd_get_timeleft,
+};
+
+static int ni903x_acpi_add(struct acpi_device *device)
+{
+ struct device *dev = &device->dev;
+ struct watchdog_device *wdd;
+ struct ni903x_wdt *wdt;
+ acpi_status status;
+ int ret;
+
+ wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
+ if (!wdt)
+ return -ENOMEM;
+
+ device->driver_data = wdt;
+ wdt->dev = dev;
+
+ status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
+ ni903x_resources, wdt);
+ if (ACPI_FAILURE(status) || wdt->io_base == 0) {
+ dev_err(dev, "failed to get resources\n");
+ return -ENODEV;
+ }
+
+ wdd = &wdt->wdd;
+ wdd->info = &ni903x_wdd_info;
+ wdd->ops = &ni903x_wdd_ops;
+ wdd->min_timeout = NIWD_MIN_TIMEOUT;
+ wdd->max_timeout = NIWD_MAX_TIMEOUT;
+ wdd->timeout = NIWD_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_err(dev, "unable to set timeout value, using default\n");
+
+ ret = watchdog_register_device(wdd);
+ if (ret) {
+ dev_err(dev, "failed to register watchdog\n");
+ return ret;
+ }
+
+ /* Switch from boot mode to user mode */
+ outb(NIWD_CONTROL_RESET | NIWD_CONTROL_MODE,
+ wdt->io_base + NIWD_CONTROL);
+
+ dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",
+ wdt->io_base, timeout, nowayout);
+
+ return 0;
+}
+
+static int ni903x_acpi_remove(struct acpi_device *device)
+{
+ struct ni903x_wdt *wdt = acpi_driver_data(device);
+
+ ni903x_wdd_stop(&wdt->wdd);
+ watchdog_unregister_device(&wdt->wdd);
+
+ return 0;
+}
+
+static const struct acpi_device_id ni903x_device_ids[] = {
+ {"NIC775C", 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, ni903x_device_ids);
+
+static struct acpi_driver ni903x_acpi_driver = {
+ .name = NIWD_NAME,
+ .ids = ni903x_device_ids,
+ .ops = {
+ .add = ni903x_acpi_add,
+ .remove = ni903x_acpi_remove,
+ },
+};
+
+module_acpi_driver(ni903x_acpi_driver);
+
+MODULE_DESCRIPTION("NI 903x Watchdog");
+MODULE_AUTHOR("Jeff Westfahl <jeff.westfahl@ni.com>");
+MODULE_AUTHOR("Kyle Roeschley <kyle.roeschley@ni.com>");
+MODULE_LICENSE("GPL");