summaryrefslogtreecommitdiffstats
path: root/drivers/watchdog/mena21_wdt.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/watchdog/mena21_wdt.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/watchdog/mena21_wdt.c')
-rw-r--r--drivers/watchdog/mena21_wdt.c228
1 files changed, 228 insertions, 0 deletions
diff --git a/drivers/watchdog/mena21_wdt.c b/drivers/watchdog/mena21_wdt.c
new file mode 100644
index 000000000..99d2359d5
--- /dev/null
+++ b/drivers/watchdog/mena21_wdt.c
@@ -0,0 +1,228 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Watchdog driver for the A21 VME CPU Boards
+ *
+ * Copyright (C) 2013 MEN Mikro Elektronik Nuernberg GmbH
+ *
+ */
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+#include <linux/uaccess.h>
+#include <linux/gpio/consumer.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/of.h>
+
+#define NUM_GPIOS 6
+
+enum a21_wdt_gpios {
+ GPIO_WD_ENAB,
+ GPIO_WD_FAST,
+ GPIO_WD_TRIG,
+ GPIO_WD_RST0,
+ GPIO_WD_RST1,
+ GPIO_WD_RST2,
+};
+
+struct a21_wdt_drv {
+ struct watchdog_device wdt;
+ struct gpio_desc *gpios[NUM_GPIOS];
+};
+
+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 unsigned int a21_wdt_get_bootstatus(struct a21_wdt_drv *drv)
+{
+ int reset = 0;
+
+ reset |= gpiod_get_value(drv->gpios[GPIO_WD_RST0]) ? (1 << 0) : 0;
+ reset |= gpiod_get_value(drv->gpios[GPIO_WD_RST1]) ? (1 << 1) : 0;
+ reset |= gpiod_get_value(drv->gpios[GPIO_WD_RST2]) ? (1 << 2) : 0;
+
+ return reset;
+}
+
+static int a21_wdt_start(struct watchdog_device *wdt)
+{
+ struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
+
+ gpiod_set_value(drv->gpios[GPIO_WD_ENAB], 1);
+
+ return 0;
+}
+
+static int a21_wdt_stop(struct watchdog_device *wdt)
+{
+ struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
+
+ gpiod_set_value(drv->gpios[GPIO_WD_ENAB], 0);
+
+ return 0;
+}
+
+static int a21_wdt_ping(struct watchdog_device *wdt)
+{
+ struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
+
+ gpiod_set_value(drv->gpios[GPIO_WD_TRIG], 0);
+ ndelay(10);
+ gpiod_set_value(drv->gpios[GPIO_WD_TRIG], 1);
+
+ return 0;
+}
+
+static int a21_wdt_set_timeout(struct watchdog_device *wdt,
+ unsigned int timeout)
+{
+ struct a21_wdt_drv *drv = watchdog_get_drvdata(wdt);
+
+ if (timeout != 1 && timeout != 30) {
+ dev_err(wdt->parent, "Only 1 and 30 allowed as timeout\n");
+ return -EINVAL;
+ }
+
+ if (timeout == 30 && wdt->timeout == 1) {
+ dev_err(wdt->parent,
+ "Transition from fast to slow mode not allowed\n");
+ return -EINVAL;
+ }
+
+ if (timeout == 1)
+ gpiod_set_value(drv->gpios[GPIO_WD_FAST], 1);
+ else
+ gpiod_set_value(drv->gpios[GPIO_WD_FAST], 0);
+
+ wdt->timeout = timeout;
+
+ return 0;
+}
+
+static const struct watchdog_info a21_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "MEN A21 Watchdog",
+};
+
+static const struct watchdog_ops a21_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = a21_wdt_start,
+ .stop = a21_wdt_stop,
+ .ping = a21_wdt_ping,
+ .set_timeout = a21_wdt_set_timeout,
+};
+
+static struct watchdog_device a21_wdt = {
+ .info = &a21_wdt_info,
+ .ops = &a21_wdt_ops,
+ .min_timeout = 1,
+ .max_timeout = 30,
+};
+
+static int a21_wdt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct a21_wdt_drv *drv;
+ unsigned int reset = 0;
+ int num_gpios;
+ int ret;
+ int i;
+
+ drv = devm_kzalloc(dev, sizeof(struct a21_wdt_drv), GFP_KERNEL);
+ if (!drv)
+ return -ENOMEM;
+
+ num_gpios = gpiod_count(dev, NULL);
+ if (num_gpios != NUM_GPIOS) {
+ dev_err(dev, "gpios DT property wrong, got %d want %d",
+ num_gpios, NUM_GPIOS);
+ return -ENODEV;
+ }
+
+ /* Request the used GPIOs */
+ for (i = 0; i < num_gpios; i++) {
+ enum gpiod_flags gflags;
+
+ if (i < GPIO_WD_RST0)
+ gflags = GPIOD_ASIS;
+ else
+ gflags = GPIOD_IN;
+ drv->gpios[i] = devm_gpiod_get_index(dev, NULL, i, gflags);
+ if (IS_ERR(drv->gpios[i]))
+ return PTR_ERR(drv->gpios[i]);
+
+ gpiod_set_consumer_name(drv->gpios[i], "MEN A21 Watchdog");
+
+ /*
+ * Retrieve the initial value from the GPIOs that should be
+ * output, then set up the line as output with that value.
+ */
+ if (i < GPIO_WD_RST0) {
+ int val;
+
+ val = gpiod_get_value(drv->gpios[i]);
+ gpiod_direction_output(drv->gpios[i], val);
+ }
+ }
+
+ watchdog_init_timeout(&a21_wdt, 30, dev);
+ watchdog_set_nowayout(&a21_wdt, nowayout);
+ watchdog_set_drvdata(&a21_wdt, drv);
+ a21_wdt.parent = dev;
+
+ reset = a21_wdt_get_bootstatus(drv);
+ if (reset == 2)
+ a21_wdt.bootstatus |= WDIOF_EXTERN1;
+ else if (reset == 4)
+ a21_wdt.bootstatus |= WDIOF_CARDRESET;
+ else if (reset == 5)
+ a21_wdt.bootstatus |= WDIOF_POWERUNDER;
+ else if (reset == 7)
+ a21_wdt.bootstatus |= WDIOF_EXTERN2;
+
+ drv->wdt = a21_wdt;
+ dev_set_drvdata(dev, drv);
+
+ ret = devm_watchdog_register_device(dev, &a21_wdt);
+ if (ret)
+ return ret;
+
+ dev_info(dev, "MEN A21 watchdog timer driver enabled\n");
+
+ return 0;
+}
+
+static void a21_wdt_shutdown(struct platform_device *pdev)
+{
+ struct a21_wdt_drv *drv = dev_get_drvdata(&pdev->dev);
+
+ gpiod_set_value(drv->gpios[GPIO_WD_ENAB], 0);
+}
+
+static const struct of_device_id a21_wdt_ids[] = {
+ { .compatible = "men,a021-wdt" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, a21_wdt_ids);
+
+static struct platform_driver a21_wdt_driver = {
+ .probe = a21_wdt_probe,
+ .shutdown = a21_wdt_shutdown,
+ .driver = {
+ .name = "a21-watchdog",
+ .of_match_table = a21_wdt_ids,
+ },
+};
+
+module_platform_driver(a21_wdt_driver);
+
+MODULE_AUTHOR("MEN Mikro Elektronik");
+MODULE_DESCRIPTION("MEN A21 Watchdog");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:a21-watchdog");