* [PATCH v2 0/4] watchdog: Introduce new driver to support ST's Watchdog
@ 2014-10-07 14:36 Lee Jones
2014-10-07 14:36 ` [PATCH 1/4] ARM: STi: DT: STiH407: Add Device Tree node for LPC Watchdog Lee Jones
` (3 more replies)
0 siblings, 4 replies; 6+ messages in thread
From: Lee Jones @ 2014-10-07 14:36 UTC (permalink / raw)
To: linux-arm-kernel
Hi Wim,
Basic driver to support ST's LPC Watchdog device.
Kind regards,
Lee
v1 => v2:
- Fixed reset enable masks
- Fixed DT documentation
Lee Jones (4):
ARM: STi: DT: STiH407: Add Device Tree node for LPC Watchdog
ARM: multi_v7_defconfig: Enable support for ST's LPC Watchdog
watchdog: st_wdt: Provide binding documentation for ST's LPC Watchdog
driver
watchdog: st_wdt: Add new driver for ST's LPC Watchdog
.../devicetree/bindings/watchdog/st-lpc-wdt.txt | 30 ++
arch/arm/boot/dts/stih407.dtsi | 10 +
arch/arm/configs/multi_v7_defconfig | 1 +
drivers/watchdog/Kconfig | 16 +
drivers/watchdog/Makefile | 1 +
drivers/watchdog/st_wdt.c | 325 +++++++++++++++++++++
6 files changed, 383 insertions(+)
create mode 100644 Documentation/devicetree/bindings/watchdog/st-lpc-wdt.txt
create mode 100644 drivers/watchdog/st_wdt.c
--
1.9.1
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH 1/4] ARM: STi: DT: STiH407: Add Device Tree node for LPC Watchdog
2014-10-07 14:36 [PATCH v2 0/4] watchdog: Introduce new driver to support ST's Watchdog Lee Jones
@ 2014-10-07 14:36 ` Lee Jones
2014-10-07 14:36 ` [PATCH 2/4] ARM: multi_v7_defconfig: Enable support for ST's " Lee Jones
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Lee Jones @ 2014-10-07 14:36 UTC (permalink / raw)
To: linux-arm-kernel
Signed-off-by: David Paris <david.paris@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
arch/arm/boot/dts/stih407.dtsi | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/arch/arm/boot/dts/stih407.dtsi b/arch/arm/boot/dts/stih407.dtsi
index f539627a..303df6c 100644
--- a/arch/arm/boot/dts/stih407.dtsi
+++ b/arch/arm/boot/dts/stih407.dtsi
@@ -259,5 +259,15 @@
status = "disabled";
};
+
+ watchdog at 0x8787000 {
+ compatible = "st,stih407-watchdog";
+ reg = <0x8787000 0x1000>, <0x204 0x4>;
+ reg-names = "base", "syscfg-en";
+ clock-names = "st_wdog";
+ clocks = <&clk_s_d3_flexgen CLK_LPC_0>;
+ timeout-sec = <600>;
+ st,syscfg = <&syscfg_core>;
+ };
};
};
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 2/4] ARM: multi_v7_defconfig: Enable support for ST's LPC Watchdog
2014-10-07 14:36 [PATCH v2 0/4] watchdog: Introduce new driver to support ST's Watchdog Lee Jones
2014-10-07 14:36 ` [PATCH 1/4] ARM: STi: DT: STiH407: Add Device Tree node for LPC Watchdog Lee Jones
@ 2014-10-07 14:36 ` Lee Jones
2014-10-07 14:36 ` [PATCH 3/4] watchdog: st_wdt: Provide binding documentation for ST's LPC Watchdog driver Lee Jones
2014-10-07 14:36 ` [PATCH 4/4] watchdog: st_wdt: Add new driver for ST's LPC Watchdog Lee Jones
3 siblings, 0 replies; 6+ messages in thread
From: Lee Jones @ 2014-10-07 14:36 UTC (permalink / raw)
To: linux-arm-kernel
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
arch/arm/configs/multi_v7_defconfig | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm/configs/multi_v7_defconfig b/arch/arm/configs/multi_v7_defconfig
index 5fb95fb..034aeab 100644
--- a/arch/arm/configs/multi_v7_defconfig
+++ b/arch/arm/configs/multi_v7_defconfig
@@ -238,6 +238,7 @@ CONFIG_ST_THERMAL_SYSCFG=y
CONFIG_ST_THERMAL_MEMMAP=y
CONFIG_WATCHDOG=y
CONFIG_ORION_WATCHDOG=y
+CONFIG_ST_WATCHDOG=y
CONFIG_SUNXI_WATCHDOG=y
CONFIG_MFD_AS3722=y
CONFIG_MFD_BCM590XX=y
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 3/4] watchdog: st_wdt: Provide binding documentation for ST's LPC Watchdog driver
2014-10-07 14:36 [PATCH v2 0/4] watchdog: Introduce new driver to support ST's Watchdog Lee Jones
2014-10-07 14:36 ` [PATCH 1/4] ARM: STi: DT: STiH407: Add Device Tree node for LPC Watchdog Lee Jones
2014-10-07 14:36 ` [PATCH 2/4] ARM: multi_v7_defconfig: Enable support for ST's " Lee Jones
@ 2014-10-07 14:36 ` Lee Jones
2014-10-07 14:36 ` [PATCH 4/4] watchdog: st_wdt: Add new driver for ST's LPC Watchdog Lee Jones
3 siblings, 0 replies; 6+ messages in thread
From: Lee Jones @ 2014-10-07 14:36 UTC (permalink / raw)
To: linux-arm-kernel
Cc: devicetree at vger.kernel.org
Signed-off-by: David Paris <david.paris@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
.../devicetree/bindings/watchdog/st-lpc-wdt.txt | 30 ++++++++++++++++++++++
1 file changed, 30 insertions(+)
create mode 100644 Documentation/devicetree/bindings/watchdog/st-lpc-wdt.txt
diff --git a/Documentation/devicetree/bindings/watchdog/st-lpc-wdt.txt b/Documentation/devicetree/bindings/watchdog/st-lpc-wdt.txt
new file mode 100644
index 0000000..520ce90
--- /dev/null
+++ b/Documentation/devicetree/bindings/watchdog/st-lpc-wdt.txt
@@ -0,0 +1,30 @@
+STMicroelectronics LPC Watchdog
+===============================
+
+Required properties
+
+- compatible : Must be one of:
+ "st,stih407-watchdog"
+ "st,stih416-watchdog"
+ "st,stih415-watchdog"
+ "st,stid127-watchdog"
+- reg : LPC registers base address + range
+- reg-names : Register map "base" and "syscfg-en" are compulsory. "type" is
+ platform dependent and not required for the STiH407
+- clock-names : Should be "lpc_wdt"
+- clocks : Clock used by LPC device
+- timeout-sec : Watchdog timeout in seconds
+- st,syscfg : Syscfg node used to configure CPU reset type and mask
+- st,warm_reset : If present, reset type will be 'warm'. If not, it will be cold
+
+Example:
+ watchdog at fde05000 {
+ compatible = "st,stih416-lpc-watchdog";
+ reg = <0xfde05000 0x1000> <0x204 0x4>;
+ reg-names = "base", "syscfg-en"
+ clock-names = "lpc_wdt";
+ clocks = <&clk_s_d3_flexgen CLK_LPC_0>;
+ timeout-sec = <600>;
+ st,syscfg = <&syscfg_core>;
+ st,warm_reset;
+ };
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 4/4] watchdog: st_wdt: Add new driver for ST's LPC Watchdog
2014-10-07 14:36 [PATCH v2 0/4] watchdog: Introduce new driver to support ST's Watchdog Lee Jones
` (2 preceding siblings ...)
2014-10-07 14:36 ` [PATCH 3/4] watchdog: st_wdt: Provide binding documentation for ST's LPC Watchdog driver Lee Jones
@ 2014-10-07 14:36 ` Lee Jones
2014-10-07 17:23 ` Guenter Roeck
3 siblings, 1 reply; 6+ messages in thread
From: Lee Jones @ 2014-10-07 14:36 UTC (permalink / raw)
To: linux-arm-kernel
Signed-off-by: David Paris <david.paris@st.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
---
drivers/watchdog/Kconfig | 16 +++
drivers/watchdog/Makefile | 1 +
drivers/watchdog/st_wdt.c | 325 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 342 insertions(+)
create mode 100644 drivers/watchdog/st_wdt.c
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index f57312f..c8abf57 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -432,6 +432,22 @@ config SIRFSOC_WATCHDOG
Support for CSR SiRFprimaII and SiRFatlasVI watchdog. When
the watchdog triggers the system will be reset.
+config ST_WATCHDOG
+ tristate "STMicroelectronics LPC Watchdog"
+ depends on ARCH_STI && OF
+ depends on !RTC_DRV_ST_LPC
+ select WATCHDOG_CORE
+ help
+ Say Y here to include Watchdog timer support for the watchdog
+ existing in the LPC of STMicroelectronics SOCs.
+ !!! BE CARREFUL !!!
+ This driver shares hardware resources with RTC Alarm part of the
+ LPC. Both LPC Watchdog driver and LPC RTC driver cannot be
+ used together.
+
+ To compile this driver as a module, choose M here: the
+ module will be called st-wdt.
+
config TEGRA_WATCHDOG
tristate "Tegra watchdog"
depends on ARCH_TEGRA || COMPILE_TEST
diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
index 468c320..eb19937 100644
--- a/drivers/watchdog/Makefile
+++ b/drivers/watchdog/Makefile
@@ -57,6 +57,7 @@ obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o
obj-$(CONFIG_BCM2835_WDT) += bcm2835_wdt.o
obj-$(CONFIG_MOXART_WDT) += moxart_wdt.o
obj-$(CONFIG_SIRFSOC_WATCHDOG) += sirfsoc_wdt.o
+obj-$(CONFIG_ST_WATCHDOG) += st_wdt.o
obj-$(CONFIG_BCM_KONA_WDT) += bcm_kona_wdt.o
obj-$(CONFIG_TEGRA_WATCHDOG) += tegra_wdt.o
diff --git a/drivers/watchdog/st_wdt.c b/drivers/watchdog/st_wdt.c
new file mode 100644
index 0000000..97ead2b
--- /dev/null
+++ b/drivers/watchdog/st_wdt.c
@@ -0,0 +1,325 @@
+/*
+ * st-wdt.c -- ST's LPC Watchdog
+ *
+ * Copyright (C) 2014 STMicroelectronics -- All Rights Reserved
+ *
+ * Author: David Paris <david.paris@st.com> for STMicroelectronics
+ * Contributor: Lee Jones <lee.jones@linaro.org> for STMicroelectronics
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/watchdog.h>
+
+/* Low Power Alarm */
+#define LPC_LPA_LSB_OFF 0x410
+#define LPC_LPA_START_OFF 0x418
+
+/* LPC as WDT */
+#define LPC_WDT_OFF 0x510
+
+#define WATCHDOG_MIN 1
+#define WATCHDOG_MAX32 4294967 /* 32bit resolution */
+
+#define WDT_ENABLE 1
+#define WDT_DISABLE 0
+
+struct st_wdog_syscfg {
+ struct regmap *regmap;
+ unsigned int type_reg;
+ unsigned int type_mask;
+ unsigned int enable_reg;
+ unsigned int enable_mask;
+};
+
+struct st_wdog {
+ void __iomem *base;
+ struct device *dev;
+ struct st_wdog_syscfg *syscfg;
+ struct clk *clk;
+ int warm_reset;
+};
+
+static struct st_wdog_syscfg stid127_syscfg = {
+ .type_mask = BIT(2),
+ .enable_mask = BIT(2),
+};
+
+static struct st_wdog_syscfg stih415_syscfg = {
+ .type_mask = BIT(6),
+ .enable_mask = BIT(7),
+};
+
+static struct st_wdog_syscfg stih416_syscfg = {
+ .type_mask = BIT(6),
+ .enable_mask = BIT(7),
+};
+
+static struct st_wdog_syscfg stih407_syscfg = {
+ .enable_mask = BIT(19),
+};
+
+static struct of_device_id st_wdog_match[] = {
+ {
+ .compatible = "st,stih407-watchdog",
+ .data = (void *)&stih407_syscfg,
+ },
+ {
+ .compatible = "st,stih416-watchdog",
+ .data = (void *)&stih416_syscfg,
+ },
+ {
+ .compatible = "st,stih415-watchdog",
+ .data = (void *)&stih415_syscfg,
+ },
+ {
+ .compatible = "st,stid127-watchdog",
+ .data = (void *)&stid127_syscfg,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, st_wdog_match);
+
+static void st_wdog_setup(struct st_wdog *st_wdog, bool enable)
+{
+ /* Type of watchdog reset - 0: Cold 1: Warm */
+ if (st_wdog->syscfg->type_reg)
+ regmap_update_bits(st_wdog->syscfg->regmap,
+ st_wdog->syscfg->type_reg,
+ st_wdog->syscfg->type_mask,
+ st_wdog->warm_reset);
+
+ /* Mask/unmask watchdog reset */
+ regmap_update_bits(st_wdog->syscfg->regmap,
+ st_wdog->syscfg->enable_reg,
+ st_wdog->syscfg->enable_mask,
+ enable ? 0 : st_wdog->syscfg->enable_mask);
+}
+
+static void st_wdog_load_timer(struct st_wdog *st_wdog, unsigned int timeout)
+{
+ unsigned long clkrate = clk_get_rate(st_wdog->clk);
+ int maxtimeout = 0xFFFFFFFF / clkrate;
+
+ if (timeout > maxtimeout) {
+ dev_warn(st_wdog->dev,
+ "timer overrun detected at current freq (%dHz)\n"
+ "wdog timeout set for %ds instead of requested %ds",
+ clkrate, maxtimeout, timeout);
+ timeout = maxtimeout;
+ }
+ timeout *= clkrate;
+
+ writel_relaxed(timeout, st_wdog->base + LPC_LPA_LSB_OFF);
+ writel_relaxed(1, st_wdog->base + LPC_LPA_START_OFF);
+}
+
+static int st_wdog_start(struct watchdog_device *wdd)
+{
+ struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
+
+ writel_relaxed(1, st_wdog->base + LPC_WDT_OFF);
+
+ return 0;
+}
+
+static int st_wdog_stop(struct watchdog_device *wdd)
+{
+ struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
+
+ writel_relaxed(0, st_wdog->base + LPC_WDT_OFF);
+
+ return 0;
+}
+
+static int st_wdog_set_timeout(struct watchdog_device *wdd,
+ unsigned int timeout)
+{
+ struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
+
+ wdd->timeout = timeout;
+ st_wdog_load_timer(st_wdog, timeout);
+
+ return 0;
+}
+
+static int st_wdog_keepalive(struct watchdog_device *wdd)
+{
+ struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
+
+ st_wdog_load_timer(st_wdog, wdd->timeout);
+
+ return 0;
+}
+
+static const struct watchdog_info st_wdog_info = {
+ .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+ .identity = "ST LPC WDT",
+};
+
+static const struct watchdog_ops st_wdog_ops = {
+ .owner = THIS_MODULE,
+ .start = st_wdog_start,
+ .stop = st_wdog_stop,
+ .ping = st_wdog_keepalive,
+ .set_timeout = st_wdog_set_timeout,
+};
+
+static struct watchdog_device st_wdog_dev = {
+ .info = &st_wdog_info,
+ .ops = &st_wdog_ops,
+ .min_timeout = WATCHDOG_MIN,
+ .max_timeout = WATCHDOG_MAX32,
+};
+
+static int st_wdog_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
+ struct device_node *np = pdev->dev.of_node;
+ struct st_wdog *st_wdog;
+ struct regmap *regmap;
+ struct resource *res;
+ struct clk *clk;
+ void __iomem *base;
+ int ret;
+
+ st_wdog = devm_kzalloc(&pdev->dev, sizeof(*st_wdog), GFP_KERNEL);
+ if (!st_wdog)
+ return -ENOMEM;
+
+ match = of_match_device(st_wdog_match, &pdev->dev);
+ if (!match) {
+ dev_err(&pdev->dev, "Couldn't match device\n");
+ return -ENODEV;
+ }
+ st_wdog->syscfg = (struct st_wdog_syscfg *)match->data;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "base");
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base)) {
+ dev_err(&pdev->dev, "Failed to ioremap base\n");
+ return PTR_ERR(base);
+ }
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-en");
+ if (!res) {
+ dev_err(&pdev->dev, "Failed to get enable register address\n");
+ return -EINVAL;
+ }
+ st_wdog->syscfg->enable_reg = res->start;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-type");
+ if (res)
+ st_wdog->syscfg->type_reg = res->start;
+
+ regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+ if (IS_ERR(regmap)) {
+ dev_err(&pdev->dev, "No syscfg phandle specified\n");
+ return PTR_ERR(regmap);
+ }
+
+ clk = of_clk_get_by_name(np, "st_wdog");
+ if (IS_ERR(clk)) {
+ dev_err(&pdev->dev, "Unable to request clock\n");
+ return PTR_ERR(clk);
+ }
+ clk_prepare_enable(st_wdog->clk);
+
+ st_wdog->dev = &pdev->dev;
+ st_wdog->base = base;
+ st_wdog->clk = clk;
+ st_wdog->warm_reset = of_property_read_bool(np, "st,warm_reset");
+ st_wdog->syscfg->regmap = regmap;
+
+ watchdog_set_drvdata(&st_wdog_dev, st_wdog);
+ watchdog_set_nowayout(&st_wdog_dev, WATCHDOG_NOWAYOUT);
+
+ ret = watchdog_register_device(&st_wdog_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to register watchdog\n");
+ clk_disable_unprepare(clk);
+ return ret;
+ }
+
+ /* Init Watchdog timeout with value in DT */
+ ret = watchdog_init_timeout(&st_wdog_dev, 0, &pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to initialise watchdog timeout\n");
+ return ret;
+ }
+
+ st_wdog_setup(st_wdog, WDT_ENABLE);
+
+ dev_info(&pdev->dev, "LPC Watchdog driver registered, reset type is %s",
+ st_wdog->warm_reset ? "warm" : "cold");
+
+ return ret;
+}
+
+static int st_wdog_remove(struct platform_device *pdev)
+{
+ struct st_wdog *st_wdog = watchdog_get_drvdata(&st_wdog_dev);
+
+ if (watchdog_active(&st_wdog_dev))
+ st_wdog_stop(&st_wdog_dev);
+
+ st_wdog_setup(st_wdog, WDT_DISABLE);
+
+ watchdog_unregister_device(&st_wdog_dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int st_wdog_suspend(struct device *dev)
+{
+ if (watchdog_active(&st_wdog_dev))
+ st_wdog_stop(&st_wdog_dev);
+
+ return 0;
+}
+
+static int st_wdog_resume(struct device *dev)
+{
+ struct st_wdog *st_wdog = watchdog_get_drvdata(&st_wdog_dev);
+
+ if (watchdog_active(&st_wdog_dev)) {
+ st_wdog_load_timer(st_wdog, st_wdog_dev.timeout);
+ st_wdog_start(&st_wdog_dev);
+ }
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(st_wdog_pm_ops,
+ st_wdog_suspend,
+ st_wdog_resume);
+
+static struct platform_driver st_wdog_driver = {
+ .driver = {
+ .name = "st-wdt",
+ .pm = &st_wdog_pm_ops,
+ .of_match_table = st_wdog_match,
+ },
+ .probe = st_wdog_probe,
+ .remove = st_wdog_remove,
+};
+module_platform_driver(st_wdog_driver);
+
+MODULE_AUTHOR("David PARIS <david.paris@st.com>");
+MODULE_DESCRIPTION("ST LPC Watchdog Driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH 4/4] watchdog: st_wdt: Add new driver for ST's LPC Watchdog
2014-10-07 14:36 ` [PATCH 4/4] watchdog: st_wdt: Add new driver for ST's LPC Watchdog Lee Jones
@ 2014-10-07 17:23 ` Guenter Roeck
0 siblings, 0 replies; 6+ messages in thread
From: Guenter Roeck @ 2014-10-07 17:23 UTC (permalink / raw)
To: linux-arm-kernel
On Tue, Oct 07, 2014 at 03:36:12PM +0100, Lee Jones wrote:
> Signed-off-by: David Paris <david.paris@st.com>
> Signed-off-by: Lee Jones <lee.jones@linaro.org>
> ---
> drivers/watchdog/Kconfig | 16 +++
> drivers/watchdog/Makefile | 1 +
> drivers/watchdog/st_wdt.c | 325 ++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 342 insertions(+)
> create mode 100644 drivers/watchdog/st_wdt.c
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index f57312f..c8abf57 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -432,6 +432,22 @@ config SIRFSOC_WATCHDOG
> Support for CSR SiRFprimaII and SiRFatlasVI watchdog. When
> the watchdog triggers the system will be reset.
>
> +config ST_WATCHDOG
> + tristate "STMicroelectronics LPC Watchdog"
> + depends on ARCH_STI && OF
> + depends on !RTC_DRV_ST_LPC
> + select WATCHDOG_CORE
> + help
> + Say Y here to include Watchdog timer support for the watchdog
> + existing in the LPC of STMicroelectronics SOCs.
> + !!! BE CARREFUL !!!
> + This driver shares hardware resources with RTC Alarm part of the
> + LPC. Both LPC Watchdog driver and LPC RTC driver cannot be
> + used together.
> +
> + To compile this driver as a module, choose M here: the
> + module will be called st-wdt.
> +
> config TEGRA_WATCHDOG
> tristate "Tegra watchdog"
> depends on ARCH_TEGRA || COMPILE_TEST
> diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile
> index 468c320..eb19937 100644
> --- a/drivers/watchdog/Makefile
> +++ b/drivers/watchdog/Makefile
> @@ -57,6 +57,7 @@ obj-$(CONFIG_RETU_WATCHDOG) += retu_wdt.o
> obj-$(CONFIG_BCM2835_WDT) += bcm2835_wdt.o
> obj-$(CONFIG_MOXART_WDT) += moxart_wdt.o
> obj-$(CONFIG_SIRFSOC_WATCHDOG) += sirfsoc_wdt.o
> +obj-$(CONFIG_ST_WATCHDOG) += st_wdt.o
> obj-$(CONFIG_BCM_KONA_WDT) += bcm_kona_wdt.o
> obj-$(CONFIG_TEGRA_WATCHDOG) += tegra_wdt.o
>
> diff --git a/drivers/watchdog/st_wdt.c b/drivers/watchdog/st_wdt.c
> new file mode 100644
> index 0000000..97ead2b
> --- /dev/null
> +++ b/drivers/watchdog/st_wdt.c
> @@ -0,0 +1,325 @@
> +/*
> + * st-wdt.c -- ST's LPC Watchdog
> + *
> + * Copyright (C) 2014 STMicroelectronics -- All Rights Reserved
> + *
> + * Author: David Paris <david.paris@st.com> for STMicroelectronics
> + * Contributor: Lee Jones <lee.jones@linaro.org> for STMicroelectronics
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public Licence
> + * as published by the Free Software Foundation; either version
> + * 2 of the Licence, or (at your option) any later version.
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/init.h>
> +#include <linux/io.h>
> +#include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/watchdog.h>
> +
> +/* Low Power Alarm */
> +#define LPC_LPA_LSB_OFF 0x410
> +#define LPC_LPA_START_OFF 0x418
> +
> +/* LPC as WDT */
> +#define LPC_WDT_OFF 0x510
> +
> +#define WATCHDOG_MIN 1
> +#define WATCHDOG_MAX32 4294967 /* 32bit resolution */
> +
> +#define WDT_ENABLE 1
> +#define WDT_DISABLE 0
Used as bool, so maybe should be true / false (though I am not sure if
those defines are really needed)
> +
> +struct st_wdog_syscfg {
> + struct regmap *regmap;
> + unsigned int type_reg;
> + unsigned int type_mask;
> + unsigned int enable_reg;
> + unsigned int enable_mask;
> +};
> +
> +struct st_wdog {
> + void __iomem *base;
> + struct device *dev;
> + struct st_wdog_syscfg *syscfg;
> + struct clk *clk;
> + int warm_reset;
> +};
> +
> +static struct st_wdog_syscfg stid127_syscfg = {
> + .type_mask = BIT(2),
> + .enable_mask = BIT(2),
> +};
> +
> +static struct st_wdog_syscfg stih415_syscfg = {
> + .type_mask = BIT(6),
> + .enable_mask = BIT(7),
> +};
> +
> +static struct st_wdog_syscfg stih416_syscfg = {
> + .type_mask = BIT(6),
> + .enable_mask = BIT(7),
> +};
> +
> +static struct st_wdog_syscfg stih407_syscfg = {
> + .enable_mask = BIT(19),
> +};
> +
> +static struct of_device_id st_wdog_match[] = {
> + {
> + .compatible = "st,stih407-watchdog",
> + .data = (void *)&stih407_syscfg,
> + },
> + {
> + .compatible = "st,stih416-watchdog",
> + .data = (void *)&stih416_syscfg,
> + },
> + {
> + .compatible = "st,stih415-watchdog",
> + .data = (void *)&stih415_syscfg,
> + },
> + {
> + .compatible = "st,stid127-watchdog",
> + .data = (void *)&stid127_syscfg,
> + },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, st_wdog_match);
> +
> +static void st_wdog_setup(struct st_wdog *st_wdog, bool enable)
> +{
> + /* Type of watchdog reset - 0: Cold 1: Warm */
> + if (st_wdog->syscfg->type_reg)
> + regmap_update_bits(st_wdog->syscfg->regmap,
> + st_wdog->syscfg->type_reg,
> + st_wdog->syscfg->type_mask,
> + st_wdog->warm_reset);
> +
> + /* Mask/unmask watchdog reset */
> + regmap_update_bits(st_wdog->syscfg->regmap,
> + st_wdog->syscfg->enable_reg,
> + st_wdog->syscfg->enable_mask,
> + enable ? 0 : st_wdog->syscfg->enable_mask);
> +}
> +
> +static void st_wdog_load_timer(struct st_wdog *st_wdog, unsigned int timeout)
> +{
> + unsigned long clkrate = clk_get_rate(st_wdog->clk);
> + int maxtimeout = 0xFFFFFFFF / clkrate;
> +
> + if (timeout > maxtimeout) {
> + dev_warn(st_wdog->dev,
> + "timer overrun detected at current freq (%dHz)\n"
> + "wdog timeout set for %ds instead of requested %ds",
> + clkrate, maxtimeout, timeout);
> + timeout = maxtimeout;
> + }
> + timeout *= clkrate;
> +
> + writel_relaxed(timeout, st_wdog->base + LPC_LPA_LSB_OFF);
> + writel_relaxed(1, st_wdog->base + LPC_LPA_START_OFF);
> +}
> +
> +static int st_wdog_start(struct watchdog_device *wdd)
> +{
> + struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
> +
> + writel_relaxed(1, st_wdog->base + LPC_WDT_OFF);
> +
> + return 0;
> +}
> +
> +static int st_wdog_stop(struct watchdog_device *wdd)
> +{
> + struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
> +
> + writel_relaxed(0, st_wdog->base + LPC_WDT_OFF);
> +
> + return 0;
> +}
> +
> +static int st_wdog_set_timeout(struct watchdog_device *wdd,
> + unsigned int timeout)
> +{
> + struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
> +
> + wdd->timeout = timeout;
> + st_wdog_load_timer(st_wdog, timeout);
> +
> + return 0;
> +}
> +
> +static int st_wdog_keepalive(struct watchdog_device *wdd)
> +{
> + struct st_wdog *st_wdog = watchdog_get_drvdata(wdd);
> +
> + st_wdog_load_timer(st_wdog, wdd->timeout);
> +
> + return 0;
> +}
> +
> +static const struct watchdog_info st_wdog_info = {
> + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
> + .identity = "ST LPC WDT",
> +};
> +
> +static const struct watchdog_ops st_wdog_ops = {
> + .owner = THIS_MODULE,
> + .start = st_wdog_start,
> + .stop = st_wdog_stop,
> + .ping = st_wdog_keepalive,
> + .set_timeout = st_wdog_set_timeout,
> +};
> +
> +static struct watchdog_device st_wdog_dev = {
> + .info = &st_wdog_info,
> + .ops = &st_wdog_ops,
> + .min_timeout = WATCHDOG_MIN,
> + .max_timeout = WATCHDOG_MAX32,
> +};
> +
> +static int st_wdog_probe(struct platform_device *pdev)
> +{
> + const struct of_device_id *match;
> + struct device_node *np = pdev->dev.of_node;
> + struct st_wdog *st_wdog;
> + struct regmap *regmap;
> + struct resource *res;
> + struct clk *clk;
> + void __iomem *base;
> + int ret;
> +
> + st_wdog = devm_kzalloc(&pdev->dev, sizeof(*st_wdog), GFP_KERNEL);
> + if (!st_wdog)
> + return -ENOMEM;
> +
> + match = of_match_device(st_wdog_match, &pdev->dev);
> + if (!match) {
> + dev_err(&pdev->dev, "Couldn't match device\n");
> + return -ENODEV;
> + }
> + st_wdog->syscfg = (struct st_wdog_syscfg *)match->data;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "base");
> + base = devm_ioremap_resource(&pdev->dev, res);
> + if (IS_ERR(base)) {
> + dev_err(&pdev->dev, "Failed to ioremap base\n");
> + return PTR_ERR(base);
> + }
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-en");
> + if (!res) {
> + dev_err(&pdev->dev, "Failed to get enable register address\n");
> + return -EINVAL;
> + }
> + st_wdog->syscfg->enable_reg = res->start;
> +
> + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "syscfg-type");
> + if (res)
> + st_wdog->syscfg->type_reg = res->start;
> +
> + regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
> + if (IS_ERR(regmap)) {
> + dev_err(&pdev->dev, "No syscfg phandle specified\n");
> + return PTR_ERR(regmap);
> + }
> +
> + clk = of_clk_get_by_name(np, "st_wdog");
> + if (IS_ERR(clk)) {
> + dev_err(&pdev->dev, "Unable to request clock\n");
> + return PTR_ERR(clk);
> + }
> + clk_prepare_enable(st_wdog->clk);
> +
> + st_wdog->dev = &pdev->dev;
> + st_wdog->base = base;
> + st_wdog->clk = clk;
> + st_wdog->warm_reset = of_property_read_bool(np, "st,warm_reset");
> + st_wdog->syscfg->regmap = regmap;
> +
> + watchdog_set_drvdata(&st_wdog_dev, st_wdog);
> + watchdog_set_nowayout(&st_wdog_dev, WATCHDOG_NOWAYOUT);
> +
> + ret = watchdog_register_device(&st_wdog_dev);
> + if (ret) {
> + dev_err(&pdev->dev, "Unable to register watchdog\n");
> + clk_disable_unprepare(clk);
> + return ret;
> + }
> +
> + /* Init Watchdog timeout with value in DT */
> + ret = watchdog_init_timeout(&st_wdog_dev, 0, &pdev->dev);
> + if (ret) {
> + dev_err(&pdev->dev, "Unable to initialise watchdog timeout\n");
> + return ret;
> + }
You should make that call prior to calling watchdog_register_device,
and clk_disable_unprepare is missing.
> +
> + st_wdog_setup(st_wdog, WDT_ENABLE);
> +
> + dev_info(&pdev->dev, "LPC Watchdog driver registered, reset type is %s",
> + st_wdog->warm_reset ? "warm" : "cold");
> +
> + return ret;
> +}
> +
> +static int st_wdog_remove(struct platform_device *pdev)
> +{
> + struct st_wdog *st_wdog = watchdog_get_drvdata(&st_wdog_dev);
> +
> + if (watchdog_active(&st_wdog_dev))
> + st_wdog_stop(&st_wdog_dev);
> +
I think this effectively defeats nowayout, since that is the only time
where the function can return true at this point. Are you sure you want
to do this here ?
> + st_wdog_setup(st_wdog, WDT_DISABLE);
> +
> + watchdog_unregister_device(&st_wdog_dev);
> +
clk_disable_unprepare ?
Thanks,
Guenter
> + return 0;
> +}
> +
> +#ifdef CONFIG_PM
> +static int st_wdog_suspend(struct device *dev)
> +{
> + if (watchdog_active(&st_wdog_dev))
> + st_wdog_stop(&st_wdog_dev);
> +
> + return 0;
> +}
> +
> +static int st_wdog_resume(struct device *dev)
> +{
> + struct st_wdog *st_wdog = watchdog_get_drvdata(&st_wdog_dev);
> +
> + if (watchdog_active(&st_wdog_dev)) {
> + st_wdog_load_timer(st_wdog, st_wdog_dev.timeout);
> + st_wdog_start(&st_wdog_dev);
> + }
> +
> + return 0;
> +}
> +#endif
> +
> +static SIMPLE_DEV_PM_OPS(st_wdog_pm_ops,
> + st_wdog_suspend,
> + st_wdog_resume);
> +
> +static struct platform_driver st_wdog_driver = {
> + .driver = {
> + .name = "st-wdt",
> + .pm = &st_wdog_pm_ops,
> + .of_match_table = st_wdog_match,
> + },
> + .probe = st_wdog_probe,
> + .remove = st_wdog_remove,
> +};
> +module_platform_driver(st_wdog_driver);
> +
> +MODULE_AUTHOR("David PARIS <david.paris@st.com>");
> +MODULE_DESCRIPTION("ST LPC Watchdog Driver");
> +MODULE_LICENSE("GPL v2");
> --
> 1.9.1
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2014-10-07 17:23 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-10-07 14:36 [PATCH v2 0/4] watchdog: Introduce new driver to support ST's Watchdog Lee Jones
2014-10-07 14:36 ` [PATCH 1/4] ARM: STi: DT: STiH407: Add Device Tree node for LPC Watchdog Lee Jones
2014-10-07 14:36 ` [PATCH 2/4] ARM: multi_v7_defconfig: Enable support for ST's " Lee Jones
2014-10-07 14:36 ` [PATCH 3/4] watchdog: st_wdt: Provide binding documentation for ST's LPC Watchdog driver Lee Jones
2014-10-07 14:36 ` [PATCH 4/4] watchdog: st_wdt: Add new driver for ST's LPC Watchdog Lee Jones
2014-10-07 17:23 ` Guenter Roeck
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