watchdog: add driver for the MEN 16z069 IP-Core
Add a driver for the MEN 16z069 Watchdog and Reset Controller IP-Core.
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Michael Moese <mmoese@suse.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 192d7f7..0b1015d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9299,6 +9299,12 @@
F: drivers/hwmon/menf21bmc_hwmon.c
F: Documentation/hwmon/menf21bmc
+MEN Z069 WATCHDOG DRIVER
+M: Johannes Thumshirn <jth@kernel.org>
+L: linux-watchdog@vger.kernel.org
+S: Maintained
+F: drivers/watchdog/menz069_wdt.c
+
MESON AO CEC DRIVER FOR AMLOGIC SOCS
M: Neil Armstrong <narmstrong@baylibre.com>
L: linux-media@lists.freedesktop.org
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 9af07fd..df55d65 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -161,6 +161,16 @@
This driver can also be built as a module. If so the module
will be called menf21bmc_wdt.
+config MENZ069_WATCHDOG
+ tristate "MEN 16Z069 Watchdog"
+ depends on MCB || COMPILE_TEST
+ select WATCHDOG_CORE
+ help
+ Say Y here to include support for the MEN 16Z069 Watchdog.
+
+ This driver can also be built as a module. If so the module
+ will be called menz069_wdt.
+
config TANGOX_WATCHDOG
tristate "Sigma Designs SMP86xx/SMP87xx watchdog"
select WATCHDOG_CORE
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 1d3c6b0..bf92e7b 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -215,4 +215,5 @@
obj-$(CONFIG_ZIIRAVE_WATCHDOG) += ziirave_wdt.o
obj-$(CONFIG_SOFT_WATCHDOG) += softdog.o
obj-$(CONFIG_MENF21BMC_WATCHDOG) += menf21bmc_wdt.o
+obj-$(CONFIG_MENZ069_WATCHDOG) += menz69_wdt.o
obj-$(CONFIG_RAVE_SP_WATCHDOG) += rave-sp-wdt.o
diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c
new file mode 100644
index 0000000..ed18238
--- /dev/null
+++ b/drivers/watchdog/menz69_wdt.c
@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Watchdog driver for the MEN z069 IP-Core
+ *
+ * Copyright (C) 2018 Johannes Thumshirn <jth@kernel.org>
+ */
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mcb.h>
+#include <linux/module.h>
+#include <linux/watchdog.h>
+
+struct men_z069_drv {
+ struct watchdog_device wdt;
+ void __iomem *base;
+ struct resource *mem;
+};
+
+#define MEN_Z069_WTR 0x10
+#define MEN_Z069_WTR_WDEN BIT(15)
+#define MEN_Z069_WTR_WDET_MASK 0x7fff
+#define MEN_Z069_WVR 0x14
+
+#define MEN_Z069_TIMER_FREQ 500 /* 500 Hz */
+#define MEN_Z069_WDT_COUNTER_MIN 1
+#define MEN_Z069_WDT_COUNTER_MAX 0x7fff
+#define MEN_Z069_DEFAULT_TIMEOUT 30
+
+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 men_z069_wdt_start(struct watchdog_device *wdt)
+{
+ struct men_z069_drv *drv = watchdog_get_drvdata(wdt);
+ u16 val;
+
+ val = readw(drv->base + MEN_Z069_WTR);
+ val |= MEN_Z069_WTR_WDEN;
+ writew(val, drv->base + MEN_Z069_WTR);
+
+ return 0;
+}
+
+static int men_z069_wdt_stop(struct watchdog_device *wdt)
+{
+ struct men_z069_drv *drv = watchdog_get_drvdata(wdt);
+ u16 val;
+
+ val = readw(drv->base + MEN_Z069_WTR);
+ val &= ~MEN_Z069_WTR_WDEN;
+ writew(val, drv->base + MEN_Z069_WTR);
+
+ return 0;
+}
+
+static int men_z069_wdt_ping(struct watchdog_device *wdt)
+{
+ struct men_z069_drv *drv = watchdog_get_drvdata(wdt);
+ u16 val;
+
+ /* The watchdog trigger value toggles between 0x5555 and 0xaaaa */
+ val = readw(drv->base + MEN_Z069_WVR);
+ val ^= 0xffff;
+ writew(val, drv->base + MEN_Z069_WVR);
+
+ return 0;
+}
+
+static int men_z069_wdt_set_timeout(struct watchdog_device *wdt,
+ unsigned int timeout)
+{
+ struct men_z069_drv *drv = watchdog_get_drvdata(wdt);
+ u16 reg, val, ena;
+
+ wdt->timeout = timeout;
+ val = timeout * MEN_Z069_TIMER_FREQ;
+
+ reg = readw(drv->base + MEN_Z069_WVR);
+ ena = reg & MEN_Z069_WTR_WDEN;
+ reg = ena | val;
+ writew(reg, drv->base + MEN_Z069_WTR);
+
+ return 0;
+}
+
+static const struct watchdog_info men_z069_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "MEN z069 Watchdog",
+};
+
+static const struct watchdog_ops men_z069_ops = {
+ .owner = THIS_MODULE,
+ .start = men_z069_wdt_start,
+ .stop = men_z069_wdt_stop,
+ .ping = men_z069_wdt_ping,
+ .set_timeout = men_z069_wdt_set_timeout,
+};
+
+static struct watchdog_device men_z069_wdt = {
+ .info = &men_z069_info,
+ .ops = &men_z069_ops,
+ .timeout = MEN_Z069_DEFAULT_TIMEOUT,
+ .min_timeout = 1,
+ .max_timeout = MEN_Z069_WDT_COUNTER_MAX / MEN_Z069_TIMER_FREQ,
+};
+
+static int men_z069_probe(struct mcb_device *dev,
+ const struct mcb_device_id *id)
+{
+ struct men_z069_drv *drv;
+ struct resource *mem;
+
+ drv = devm_kzalloc(&dev->dev, sizeof(struct men_z069_drv), GFP_KERNEL);
+ if (!drv)
+ return -ENOMEM;
+
+ mem = mcb_request_mem(dev, "z069-wdt");
+ if (IS_ERR(mem))
+ return PTR_ERR(mem);
+
+ drv->base = devm_ioremap(&dev->dev, mem->start, resource_size(mem));
+ if (drv->base == NULL)
+ goto release_mem;
+
+ drv->mem = mem;
+
+ drv->wdt = men_z069_wdt;
+ watchdog_init_timeout(&drv->wdt, 0, &dev->dev);
+ watchdog_set_nowayout(&drv->wdt, nowayout);
+ watchdog_set_drvdata(&drv->wdt, drv);
+ drv->wdt.parent = &dev->dev;
+ mcb_set_drvdata(dev, drv);
+
+ return watchdog_register_device(&men_z069_wdt);
+
+release_mem:
+ mcb_release_mem(mem);
+ return -ENOMEM;
+}
+
+static void men_z069_remove(struct mcb_device *dev)
+{
+ struct men_z069_drv *drv = mcb_get_drvdata(dev);
+
+ watchdog_unregister_device(&drv->wdt);
+ mcb_release_mem(drv->mem);
+}
+
+static const struct mcb_device_id men_z069_ids[] = {
+ { .device = 0x45 },
+ { }
+};
+MODULE_DEVICE_TABLE(mcb, men_z069_ids);
+
+static struct mcb_driver men_z069_driver = {
+ .driver = {
+ .name = "z069-wdt",
+ .owner = THIS_MODULE,
+ },
+ .probe = men_z069_probe,
+ .remove = men_z069_remove,
+ .id_table = men_z069_ids,
+};
+module_mcb_driver(men_z069_driver);
+
+MODULE_AUTHOR("Johannes Thumshirn <jth@kernel.org>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("mcb:16z069");
