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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/watchdog/wm831x_wdt.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/watchdog/wm831x_wdt.c')
-rw-r--r--drivers/watchdog/wm831x_wdt.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/drivers/watchdog/wm831x_wdt.c b/drivers/watchdog/wm831x_wdt.c
new file mode 100644
index 000000000..d96ad8f38
--- /dev/null
+++ b/drivers/watchdog/wm831x_wdt.c
@@ -0,0 +1,258 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Watchdog driver for the wm831x PMICs
+ *
+ * Copyright (C) 2009 Wolfson Microelectronics
+ */
+
+#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/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/pdata.h>
+#include <linux/mfd/wm831x/watchdog.h>
+
+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 wm831x_wdt_drvdata {
+ struct watchdog_device wdt;
+ struct wm831x *wm831x;
+ struct mutex lock;
+ int update_state;
+};
+
+/* We can't use the sub-second values here but they're included
+ * for completeness. */
+static struct {
+ unsigned int time; /* Seconds */
+ u16 val; /* WDOG_TO value */
+} wm831x_wdt_cfgs[] = {
+ { 1, 2 },
+ { 2, 3 },
+ { 4, 4 },
+ { 8, 5 },
+ { 16, 6 },
+ { 32, 7 },
+ { 33, 7 }, /* Actually 32.768s so include both, others round down */
+};
+
+static int wm831x_wdt_start(struct watchdog_device *wdt_dev)
+{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
+ int ret;
+
+ mutex_lock(&driver_data->lock);
+
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret == 0) {
+ ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,
+ WM831X_WDOG_ENA, WM831X_WDOG_ENA);
+ wm831x_reg_lock(wm831x);
+ } else {
+ dev_err(wm831x->dev, "Failed to unlock security key: %d\n",
+ ret);
+ }
+
+ mutex_unlock(&driver_data->lock);
+
+ return ret;
+}
+
+static int wm831x_wdt_stop(struct watchdog_device *wdt_dev)
+{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
+ int ret;
+
+ mutex_lock(&driver_data->lock);
+
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret == 0) {
+ ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,
+ WM831X_WDOG_ENA, 0);
+ wm831x_reg_lock(wm831x);
+ } else {
+ dev_err(wm831x->dev, "Failed to unlock security key: %d\n",
+ ret);
+ }
+
+ mutex_unlock(&driver_data->lock);
+
+ return ret;
+}
+
+static int wm831x_wdt_ping(struct watchdog_device *wdt_dev)
+{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
+ int ret;
+ u16 reg;
+
+ mutex_lock(&driver_data->lock);
+
+ reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
+
+ if (!(reg & WM831X_WDOG_RST_SRC)) {
+ dev_err(wm831x->dev, "Hardware watchdog update unsupported\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ reg |= WM831X_WDOG_RESET;
+
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret == 0) {
+ ret = wm831x_reg_write(wm831x, WM831X_WATCHDOG, reg);
+ wm831x_reg_lock(wm831x);
+ } else {
+ dev_err(wm831x->dev, "Failed to unlock security key: %d\n",
+ ret);
+ }
+
+out:
+ mutex_unlock(&driver_data->lock);
+
+ return ret;
+}
+
+static int wm831x_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int timeout)
+{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
+ int ret, i;
+
+ for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)
+ if (wm831x_wdt_cfgs[i].time == timeout)
+ break;
+ if (i == ARRAY_SIZE(wm831x_wdt_cfgs))
+ return -EINVAL;
+
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret == 0) {
+ ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,
+ WM831X_WDOG_TO_MASK,
+ wm831x_wdt_cfgs[i].val);
+ wm831x_reg_lock(wm831x);
+ } else {
+ dev_err(wm831x->dev, "Failed to unlock security key: %d\n",
+ ret);
+ }
+
+ wdt_dev->timeout = timeout;
+
+ return ret;
+}
+
+static const struct watchdog_info wm831x_wdt_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "WM831x Watchdog",
+};
+
+static const struct watchdog_ops wm831x_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = wm831x_wdt_start,
+ .stop = wm831x_wdt_stop,
+ .ping = wm831x_wdt_ping,
+ .set_timeout = wm831x_wdt_set_timeout,
+};
+
+static int wm831x_wdt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct wm831x *wm831x = dev_get_drvdata(dev->parent);
+ struct wm831x_pdata *chip_pdata = dev_get_platdata(dev->parent);
+ struct wm831x_watchdog_pdata *pdata;
+ struct wm831x_wdt_drvdata *driver_data;
+ struct watchdog_device *wm831x_wdt;
+ int reg, ret, i;
+
+ ret = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
+ if (ret < 0) {
+ dev_err(wm831x->dev, "Failed to read watchdog status: %d\n",
+ ret);
+ return ret;
+ }
+ reg = ret;
+
+ if (reg & WM831X_WDOG_DEBUG)
+ dev_warn(wm831x->dev, "Watchdog is paused\n");
+
+ driver_data = devm_kzalloc(dev, sizeof(*driver_data), GFP_KERNEL);
+ if (!driver_data)
+ return -ENOMEM;
+
+ mutex_init(&driver_data->lock);
+ driver_data->wm831x = wm831x;
+
+ wm831x_wdt = &driver_data->wdt;
+
+ wm831x_wdt->info = &wm831x_wdt_info;
+ wm831x_wdt->ops = &wm831x_wdt_ops;
+ wm831x_wdt->parent = dev;
+ watchdog_set_nowayout(wm831x_wdt, nowayout);
+ watchdog_set_drvdata(wm831x_wdt, driver_data);
+
+ reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
+ reg &= WM831X_WDOG_TO_MASK;
+ for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)
+ if (wm831x_wdt_cfgs[i].val == reg)
+ break;
+ if (i == ARRAY_SIZE(wm831x_wdt_cfgs))
+ dev_warn(wm831x->dev,
+ "Unknown watchdog timeout: %x\n", reg);
+ else
+ wm831x_wdt->timeout = wm831x_wdt_cfgs[i].time;
+
+ /* Apply any configuration */
+ if (chip_pdata)
+ pdata = chip_pdata->watchdog;
+ else
+ pdata = NULL;
+
+ if (pdata) {
+ reg &= ~(WM831X_WDOG_SECACT_MASK | WM831X_WDOG_PRIMACT_MASK |
+ WM831X_WDOG_RST_SRC);
+
+ reg |= pdata->primary << WM831X_WDOG_PRIMACT_SHIFT;
+ reg |= pdata->secondary << WM831X_WDOG_SECACT_SHIFT;
+ reg |= pdata->software << WM831X_WDOG_RST_SRC_SHIFT;
+
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret == 0) {
+ ret = wm831x_reg_write(wm831x, WM831X_WATCHDOG, reg);
+ wm831x_reg_lock(wm831x);
+ } else {
+ dev_err(wm831x->dev,
+ "Failed to unlock security key: %d\n", ret);
+ return ret;
+ }
+ }
+
+ return devm_watchdog_register_device(dev, &driver_data->wdt);
+}
+
+static struct platform_driver wm831x_wdt_driver = {
+ .probe = wm831x_wdt_probe,
+ .driver = {
+ .name = "wm831x-watchdog",
+ },
+};
+
+module_platform_driver(wm831x_wdt_driver);
+
+MODULE_AUTHOR("Mark Brown");
+MODULE_DESCRIPTION("WM831x Watchdog");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm831x-watchdog");