Merge tag 'linux-watchdog-4.19-rc1' of git://www.linux-watchdog.org/linux-watchdog

Pull watchdog updates from Wim Van Sebroeck:

 - add MEN 16z069 IP-Core driver

 - renesas-wdt: add support for the R8A77990 wdt

 - stm32_iwdg: Add stm32mp1 support and pclk feature

 - sp805_wdt, orion_wdt, sprd_wdt: several improvements

 - imx2_wdt, stmp3xxx: switch to SPDX identifier

* tag 'linux-watchdog-4.19-rc1' of git://www.linux-watchdog.org/linux-watchdog:
  watchdog: fix dependencies of menz69_wdt.o
  watchdog: sp805: Add clock-frequency property
  watchdog: add driver for the MEN 16z069 IP-Core
  watchdog: sprd_wdt: Remove redundant dev_err call in sprd_wdt_probe()
  watchdog: stmp3xxx: Switch to SPDX identifier
  watchdog: imx2_wdt: Switch to SPDX identifier
  watchdog: sp805: set WDOG_HW_RUNNING when appropriate
  watchdog: sp805: add 'timeout-sec' DT property support
  dt-bindings: watchdog: Add optional 'timeout-sec' property for sp805
  dt-bindings: watchdog: Consolidate SP805 binding docs
  watchdog: orion_wdt: Mark watchdog as active when running at probe
  watchdog: stm32: add pclk feature for stm32mp1
  dt-bindings: watchdog: add stm32mp1 support
  dt-bindings: watchdog: renesas-wdt: Add support for the R8A77990 wdt

14 files changed, 351 insertions, 105 deletions

diff --git a/Documentation/devicetree/bindings/watchdog/arm,sp805.txt b/Documentation/devicetree/bindings/watchdog/arm,sp805.txt
index ca99d64e6211..bee6f1f0e41b 100644
--- a/Documentation/devicetree/bindings/watchdog/arm,sp805.txt
+++ b/Documentation/devicetree/bindings/watchdog/arm,sp805.txt
@@ -1,17 +1,32 @@
 ARM AMBA Primecell SP805 Watchdog
 
+SP805 WDT is a ARM Primecell Peripheral and has a standard-id register that
+can be used to identify the peripheral type, vendor, and revision.
+This value can be used for driver matching.
+
+As SP805 WDT is a primecell IP, it follows the base bindings specified in
+'arm/primecell.txt'
+
 Required properties:
-- compatible: Should be "arm,sp805" & "arm,primecell"
-- reg: Should contain location and length for watchdog timer register.
-- interrupts: Should contain the list of watchdog timer interrupts.
-- clocks: clocks driving the watchdog timer hardware. This list should be 2
-        clocks. With 2 clocks, the order is wdogclk clock, apb_pclk.
+- compatible:  Should be "arm,sp805" & "arm,primecell"
+- reg:         Should contain location and length for watchdog timer register
+- clocks:      Clocks driving the watchdog timer hardware. This list should be
+               2 clocks. With 2 clocks, the order is wdog_clk, apb_pclk
+               wdog_clk can be equal to or be a sub-multiple of the apb_pclk
+               frequency
+- clock-names: Shall be "wdog_clk" for first clock and "apb_pclk" for the
+               second one
+
+Optional properties:
+- interrupts:  Should specify WDT interrupt number
+- timeout-sec: Should specify default WDT timeout in seconds. If unset, the
+               default timeout is determined by the driver
 
 Example:
         watchdog@66090000 {
                 compatible = "arm,sp805", "arm,primecell";
                 reg = <0x66090000 0x1000>;
                 interrupts = <GIC_SPI 406 IRQ_TYPE_LEVEL_HIGH>;
-                clocks = <&apb_pclk>,<&apb_pclk>;
-                clock-names = "wdogclk", "apb_pclk";
+                clocks = <&wdt_clk>, <&apb_pclk>;
+                clock-names = "wdog_clk", "apb_pclk";
         };
diff --git a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt
index f24d802b8056..5d47a262474c 100644
--- a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt
@@ -16,6 +16,7 @@ Required properties:
                  - "renesas,r8a7796-wdt" (R-Car M3-W)
                  - "renesas,r8a77965-wdt" (R-Car M3-N)
                  - "renesas,r8a77970-wdt" (R-Car V3M)
+                 - "renesas,r8a77990-wdt" (R-Car E3)
                  - "renesas,r8a77995-wdt" (R-Car D3)
                  - "renesas,r7s72100-wdt" (RZ/A1)
                 The generic compatible string must be:
diff --git a/Documentation/devicetree/bindings/watchdog/sp805-wdt.txt b/Documentation/devicetree/bindings/watchdog/sp805-wdt.txt
deleted file mode 100644
index edc4f0ea54a3..000000000000
--- a/Documentation/devicetree/bindings/watchdog/sp805-wdt.txt
+++ /dev/null
@@ -1,31 +0,0 @@
-* ARM SP805 Watchdog Timer (WDT) Controller
-
-SP805 WDT is a ARM Primecell Peripheral and has a standard-id register that
-can be used to identify the peripheral type, vendor, and revision.
-This value can be used for driver matching.
-
-As SP805 WDT is a primecell IP, it follows the base bindings specified in
-'arm/primecell.txt'
-
-Required properties:
-- compatible : Should be "arm,sp805-wdt", "arm,primecell"
-- reg : Base address and size of the watchdog timer registers.
-- clocks : From common clock binding.
-           First clock is PCLK and the second is WDOGCLK.
-           WDOGCLK can be equal to or be a sub-multiple of the PCLK frequency.
-- clock-names : From common clock binding.
-                Shall be "apb_pclk" for first clock and "wdog_clk" for the
-                second one.
-
-Optional properties:
-- interrupts : Should specify WDT interrupt number.
-
-Examples:
-
-                cluster1_core0_watchdog: wdt@c000000 {
-                        compatible = "arm,sp805-wdt", "arm,primecell";
-                        reg = <0x0 0xc000000 0x0 0x1000>;
-                        clocks = <&clockgen 4 3>, <&clockgen 4 3>;
-                        clock-names = "apb_pclk", "wdog_clk";
-                };
-
diff --git a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
index cc13b10a3f82..d8f4430b0a13 100644
--- a/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
+++ b/Documentation/devicetree/bindings/watchdog/st,stm32-iwdg.txt
@@ -2,9 +2,15 @@ STM32 Independent WatchDoG (IWDG)
 ---------------------------------
 
 Required properties:
-- compatible: "st,stm32-iwdg"
-- reg: physical base address and length of the registers set for the device
-- clocks: must contain a single entry describing the clock input
+- compatible: Should be either:
+  - "st,stm32-iwdg"
+  - "st,stm32mp1-iwdg"
+- reg: Physical base address and length of the registers set for the device
+- clocks: Reference to the clock entry lsi. Additional pclk clock entry
+  is required only for st,stm32mp1-iwdg.
+- clock-names: Name of the clocks used.
+  "lsi" for st,stm32-iwdg
+  "lsi", "pclk" for st,stm32mp1-iwdg
 
 Optional Properties:
 - timeout-sec: Watchdog timeout value in seconds.
@@ -15,5 +21,6 @@ iwdg: watchdog@40003000 {
         compatible = "st,stm32-iwdg";
         reg = <0x40003000 0x400>;
         clocks = <&clk_lsi>;
+        clock-names = "lsi";
         timeout-sec = <32>;
 };
diff --git a/MAINTAINERS b/MAINTAINERS
index 42caef5c808d..71b8592a7264 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9427,6 +9427,12 @@ F:	drivers/leds/leds-menf21bmc.c
 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 9af07fd92763..5ea8909a41f9 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -161,6 +161,16 @@ config MENF21BMC_WATCHDOG
           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
+        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 1d3c6b094fe5..bf92e7bf9ce0 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -215,4 +215,5 @@ obj-$(CONFIG_MAX77620_WATCHDOG) += max77620_wdt.o
 obj-$(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/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index f07850d2c977..2b52514eaa86 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Watchdog driver for IMX2 and later processors
  *
@@ -7,10 +8,6 @@
  * some parts adapted by similar drivers from Darius Augulis and Vladimir
  * Zapolskiy, additional improvements by Wim Van Sebroeck.
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
  * NOTE: MX1 has a slightly different Watchdog than MX2 and later:
  *
  *                      MX1:            MX2+:
diff --git a/drivers/watchdog/menz69_wdt.c b/drivers/watchdog/menz69_wdt.c
new file mode 100644
index 000000000000..ed18238c5407
--- /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");
diff --git a/drivers/watchdog/orion_wdt.c b/drivers/watchdog/orion_wdt.c
index ea676d233e1e..9db3b09f7568 100644
--- a/drivers/watchdog/orion_wdt.c
+++ b/drivers/watchdog/orion_wdt.c
@@ -581,6 +581,8 @@ static int orion_wdt_probe(struct platform_device *pdev)
          */
         if (!orion_wdt_enabled(&dev->wdt))
                 orion_wdt_stop(&dev->wdt);
+        else
+                set_bit(WDOG_HW_RUNNING, &dev->wdt.status);
 
         /* Request the IRQ only after the watchdog is disabled */
         irq = platform_get_irq(pdev, 0);
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
index 9849db0743a7..072986d461b7 100644
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -11,6 +11,7 @@
  * warranty of any kind, whether express or implied.
  */
 
+#include <linux/acpi.h>
 #include <linux/device.h>
 #include <linux/resource.h>
 #include <linux/amba/bus.h>
@@ -22,6 +23,7 @@
 #include <linux/math64.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
+#include <linux/of.h>
 #include <linux/pm.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
@@ -42,6 +44,7 @@
         /* control register masks */
         #define INT_ENABLE      (1 << 0)
         #define RESET_ENABLE    (1 << 1)
+        #define ENABLE_MASK     (INT_ENABLE | RESET_ENABLE)
 #define WDTINTCLR               0x00C
 #define WDTRIS                  0x010
 #define WDTMIS                  0x014
@@ -65,6 +68,7 @@ struct sp805_wdt {
         spinlock_t                      lock;
         void __iomem                    *base;
         struct clk                      *clk;
+        u64                             rate;
         struct amba_device              *adev;
         unsigned int                    load_val;
 };
@@ -74,13 +78,22 @@ module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout,
                 "Set to 1 to keep watchdog running after device release");
 
+/* returns true if wdt is running; otherwise returns false */
+static bool wdt_is_running(struct watchdog_device *wdd)
+{
+        struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
+        u32 wdtcontrol = readl_relaxed(wdt->base + WDTCONTROL);
+
+        return (wdtcontrol & ENABLE_MASK) == ENABLE_MASK;
+}
+
 /* This routine finds load value that will reset system in required timout */
 static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout)
 {
         struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
         u64 load, rate;
 
-        rate = clk_get_rate(wdt->clk);
+        rate = wdt->rate;
 
         /*
          * sp805 runs counter with given value twice, after the end of first
@@ -106,9 +119,7 @@ static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout)
 static unsigned int wdt_timeleft(struct watchdog_device *wdd)
 {
         struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
-        u64 load, rate;
-
-        rate = clk_get_rate(wdt->clk);
+        u64 load;
 
         spin_lock(&wdt->lock);
         load = readl_relaxed(wdt->base + WDTVALUE);
@@ -118,7 +129,7 @@ static unsigned int wdt_timeleft(struct watchdog_device *wdd)
                 load += wdt->load_val + 1;
         spin_unlock(&wdt->lock);
 
-        return div_u64(load, rate);
+        return div_u64(load, wdt->rate);
 }
 
 static int
@@ -228,11 +239,25 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
         if (IS_ERR(wdt->base))
                 return PTR_ERR(wdt->base);
 
-        wdt->clk = devm_clk_get(&adev->dev, NULL);
-        if (IS_ERR(wdt->clk)) {
-                dev_warn(&adev->dev, "Clock not found\n");
-                ret = PTR_ERR(wdt->clk);
-                goto err;
+        if (adev->dev.of_node) {
+                wdt->clk = devm_clk_get(&adev->dev, NULL);
+                if (IS_ERR(wdt->clk)) {
+                        dev_err(&adev->dev, "Clock not found\n");
+                        return PTR_ERR(wdt->clk);
+                }
+                wdt->rate = clk_get_rate(wdt->clk);
+        } else if (has_acpi_companion(&adev->dev)) {
+                /*
+                 * When Driver probe with ACPI device, clock devices
+                 * are not available, so watchdog rate get from
+                 * clock-frequency property given in _DSD object.
+                 */
+                device_property_read_u64(&adev->dev, "clock-frequency",
+                                         &wdt->rate);
+                if (!wdt->rate) {
+                        dev_err(&adev->dev, "no clock-frequency property\n");
+                        return -ENODEV;
+                }
         }
 
         wdt->adev = adev;
@@ -244,7 +269,23 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id)
         watchdog_set_nowayout(&wdt->wdd, nowayout);
         watchdog_set_drvdata(&wdt->wdd, wdt);
         watchdog_set_restart_priority(&wdt->wdd, 128);
-        wdt_setload(&wdt->wdd, DEFAULT_TIMEOUT);
+
+        /*
+         * If 'timeout-sec' devicetree property is specified, use that.
+         * Otherwise, use DEFAULT_TIMEOUT
+         */
+        wdt->wdd.timeout = DEFAULT_TIMEOUT;
+        watchdog_init_timeout(&wdt->wdd, 0, &adev->dev);
+        wdt_setload(&wdt->wdd, wdt->wdd.timeout);
+
+        /*
+         * If HW is already running, enable/reset the wdt and set the running
+         * bit to tell the wdt subsystem
+         */
+        if (wdt_is_running(&wdt->wdd)) {
+                wdt_enable(&wdt->wdd);
+                set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
+        }
 
         ret = watchdog_register_device(&wdt->wdd);
         if (ret) {
diff --git a/drivers/watchdog/sprd_wdt.c b/drivers/watchdog/sprd_wdt.c
index b4d484a42b70..ff9397d9638a 100644
--- a/drivers/watchdog/sprd_wdt.c
+++ b/drivers/watchdog/sprd_wdt.c
@@ -279,10 +279,8 @@ static int sprd_wdt_probe(struct platform_device *pdev)
 
         wdt_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         wdt->base = devm_ioremap_resource(&pdev->dev, wdt_res);
-        if (IS_ERR(wdt->base)) {
-                dev_err(&pdev->dev, "failed to map memory resource\n");
+        if (IS_ERR(wdt->base))
                 return PTR_ERR(wdt->base);
-        }
 
         wdt->enable = devm_clk_get(&pdev->dev, "enable");
         if (IS_ERR(wdt->enable)) {
diff --git a/drivers/watchdog/stm32_iwdg.c b/drivers/watchdog/stm32_iwdg.c
index c97ad5619cb0..e00e3b3526c6 100644
--- a/drivers/watchdog/stm32_iwdg.c
+++ b/drivers/watchdog/stm32_iwdg.c
@@ -11,12 +11,13 @@
 
 #include <linux/clk.h>
 #include <linux/delay.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/watchdog.h>
 
@@ -54,11 +55,15 @@
 #define TIMEOUT_US      100000
 #define SLEEP_US        1000
 
+#define HAS_PCLK        true
+
 struct stm32_iwdg {
         struct watchdog_device  wdd;
         void __iomem            *regs;
-        struct clk              *clk;
+        struct clk              *clk_lsi;
+        struct clk              *clk_pclk;
         unsigned int            rate;
+        bool                    has_pclk;
 };
 
 static inline u32 reg_read(void __iomem *base, u32 reg)
@@ -133,6 +138,44 @@ static int stm32_iwdg_set_timeout(struct watchdog_device *wdd,
         return 0;
 }
 
+static int stm32_iwdg_clk_init(struct platform_device *pdev,
+                               struct stm32_iwdg *wdt)
+{
+        u32 ret;
+
+        wdt->clk_lsi = devm_clk_get(&pdev->dev, "lsi");
+        if (IS_ERR(wdt->clk_lsi)) {
+                dev_err(&pdev->dev, "Unable to get lsi clock\n");
+                return PTR_ERR(wdt->clk_lsi);
+        }
+
+        /* optional peripheral clock */
+        if (wdt->has_pclk) {
+                wdt->clk_pclk = devm_clk_get(&pdev->dev, "pclk");
+                if (IS_ERR(wdt->clk_pclk)) {
+                        dev_err(&pdev->dev, "Unable to get pclk clock\n");
+                        return PTR_ERR(wdt->clk_pclk);
+                }
+
+                ret = clk_prepare_enable(wdt->clk_pclk);
+                if (ret) {
+                        dev_err(&pdev->dev, "Unable to prepare pclk clock\n");
+                        return ret;
+                }
+        }
+
+        ret = clk_prepare_enable(wdt->clk_lsi);
+        if (ret) {
+                dev_err(&pdev->dev, "Unable to prepare lsi clock\n");
+                clk_disable_unprepare(wdt->clk_pclk);
+                return ret;
+        }
+
+        wdt->rate = clk_get_rate(wdt->clk_lsi);
+
+        return 0;
+}
+
 static const struct watchdog_info stm32_iwdg_info = {
         .options        = WDIOF_SETTIMEOUT |
                           WDIOF_MAGICCLOSE |
@@ -147,49 +190,42 @@ static const struct watchdog_ops stm32_iwdg_ops = {
         .set_timeout    = stm32_iwdg_set_timeout,
 };
 
+static const struct of_device_id stm32_iwdg_of_match[] = {
+        { .compatible = "st,stm32-iwdg", .data = (void *)!HAS_PCLK },
+        { .compatible = "st,stm32mp1-iwdg", .data = (void *)HAS_PCLK },
+        { /* end node */ }
+};
+MODULE_DEVICE_TABLE(of, stm32_iwdg_of_match);
+
 static int stm32_iwdg_probe(struct platform_device *pdev)
 {
         struct watchdog_device *wdd;
+        const struct of_device_id *match;
         struct stm32_iwdg *wdt;
         struct resource *res;
-        void __iomem *regs;
-        struct clk *clk;
         int ret;
 
+        match = of_match_device(stm32_iwdg_of_match, &pdev->dev);
+        if (!match)
+                return -ENODEV;
+
+        wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+        if (!wdt)
+                return -ENOMEM;
+
+        wdt->has_pclk = match->data;
+
         /* This is the timer base. */
         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-        regs = devm_ioremap_resource(&pdev->dev, res);
-        if (IS_ERR(regs)) {
+        wdt->regs = devm_ioremap_resource(&pdev->dev, res);
+        if (IS_ERR(wdt->regs)) {
                 dev_err(&pdev->dev, "Could not get resource\n");
-                return PTR_ERR(regs);
+                return PTR_ERR(wdt->regs);
         }
 
-        clk = devm_clk_get(&pdev->dev, NULL);
-        if (IS_ERR(clk)) {
-                dev_err(&pdev->dev, "Unable to get clock\n");
-                return PTR_ERR(clk);
-        }
-
-        ret = clk_prepare_enable(clk);
-        if (ret) {
-                dev_err(&pdev->dev, "Unable to prepare clock %p\n", clk);
+        ret = stm32_iwdg_clk_init(pdev, wdt);
+        if (ret)
                 return ret;
-        }
-
-        /*
-         * Allocate our watchdog driver data, which has the
-         * struct watchdog_device nested within it.
-         */
-        wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
-        if (!wdt) {
-                ret = -ENOMEM;
-                goto err;
-        }
-
-        /* Initialize struct stm32_iwdg. */
-        wdt->regs = regs;
-        wdt->clk = clk;
-        wdt->rate = clk_get_rate(clk);
 
         /* Initialize struct watchdog_device. */
         wdd = &wdt->wdd;
@@ -217,7 +253,8 @@ static int stm32_iwdg_probe(struct platform_device *pdev)
 
         return 0;
 err:
-        clk_disable_unprepare(clk);
+        clk_disable_unprepare(wdt->clk_lsi);
+        clk_disable_unprepare(wdt->clk_pclk);
 
         return ret;
 }
@@ -227,23 +264,18 @@ static int stm32_iwdg_remove(struct platform_device *pdev)
         struct stm32_iwdg *wdt = platform_get_drvdata(pdev);
 
         watchdog_unregister_device(&wdt->wdd);
-        clk_disable_unprepare(wdt->clk);
+        clk_disable_unprepare(wdt->clk_lsi);
+        clk_disable_unprepare(wdt->clk_pclk);
 
         return 0;
 }
 
-static const struct of_device_id stm32_iwdg_of_match[] = {
-        { .compatible = "st,stm32-iwdg" },
-        { /* end node */ }
-};
-MODULE_DEVICE_TABLE(of, stm32_iwdg_of_match);
-
 static struct platform_driver stm32_iwdg_driver = {
         .probe          = stm32_iwdg_probe,
         .remove         = stm32_iwdg_remove,
         .driver = {
                 .name   = "iwdg",
-                .of_match_table = stm32_iwdg_of_match,
+                .of_match_table = of_match_ptr(stm32_iwdg_of_match),
         },
 };
 module_platform_driver(stm32_iwdg_driver);
diff --git a/drivers/watchdog/stmp3xxx_rtc_wdt.c b/drivers/watchdog/stmp3xxx_rtc_wdt.c
index d8b11eb269ad..994c54cc68e9 100644
--- a/drivers/watchdog/stmp3xxx_rtc_wdt.c
+++ b/drivers/watchdog/stmp3xxx_rtc_wdt.c
@@ -1,13 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Watchdog driver for the RTC based watchdog in STMP3xxx and i.MX23/28
  *
  * Author: Wolfram Sang <kernel@pengutronix.de>
  *
  * Copyright (C) 2011-12 Wolfram Sang, Pengutronix
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
  */
 #include <linux/kernel.h>
 #include <linux/module.h>