From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-path: Received: from mail-wr1-f65.google.com ([209.85.221.65]:43813 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393753AbeKWT17 (ORCPT ); Fri, 23 Nov 2018 14:27:59 -0500 Received: by mail-wr1-f65.google.com with SMTP id r10so11479410wrs.10 for ; Fri, 23 Nov 2018 00:44:41 -0800 (PST) From: Loic Poulain To: wim@linux-watchdog.org, linux@roeck-us.net, robh+dt@kernel.org Cc: linux-arm-msm@vger.kernel.org, linux-watchdog@vger.kernel.org, devicetree@vger.kernel.org, andy.gross@linaro.org, Loic Poulain Subject: [PATCH v3 1/3] watchdog: Add pm8916 watchdog driver Date: Fri, 23 Nov 2018 09:44:36 +0100 Message-Id: <1542962678-13697-1-git-send-email-loic.poulain@linaro.org> Sender: linux-watchdog-owner@vger.kernel.org List-Id: linux-watchdog@vger.kernel.org The PM816 module is a versatile PMIC with many diverse functions integrated, including, a watchdog. This watchdog is subcomponent of the PON (Power On) peripheral, in the same way as pwrkey/resin buttons. It works with two timers (2-stages), the first one generates an IRQ to the main SoC (APQ8016/MSM8916), the second one performs the reset. This driver expects the following device hierarchy: [pm8916]->[pm8916-pon]->[pm8916-wdt] It uses the pm8916 regmap to access PM8916 registers. Signed-off-by: Loic Poulain --- v2: SPDX license headers ordering coding styles / tabs / multi-line comments pretimeout / bark interrupt WDIOF_MAGICCLOSE flag timeout init via fdt devm usage v3: Remove unused dev/irq variables from pm8916 wdt struct drivers/watchdog/Kconfig | 8 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/pm8916_wdt.c | 211 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 220 insertions(+) create mode 100644 drivers/watchdog/pm8916_wdt.c diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 2d64333..ef2c2b5 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -847,6 +847,14 @@ config SPRD_WATCHDOG Say Y here to include watchdog timer supported by Spreadtrum system. +config PM8916_WATCHDOG + tristate "QCOM PM8916 pmic watchdog" + depends on OF && MFD_SPMI_PMIC + select WATCHDOG_CORE + help + Say Y here to include support watchdog timer embedded into the + pm8916 module. + # X86 (i386 + ia64 + x86_64) Architecture config ACQUIRE_WDT diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index f69cdff..cc90e72 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -92,6 +92,7 @@ obj-$(CONFIG_STM32_WATCHDOG) += stm32_iwdg.o obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o +obj-$(CONFIG_PM8916_WATCHDOG) += pm8916_wdt.o # X86 (i386 + ia64 + x86_64) Architecture obj-$(CONFIG_ACQUIRE_WDT) += acquirewdt.o diff --git a/drivers/watchdog/pm8916_wdt.c b/drivers/watchdog/pm8916_wdt.c new file mode 100644 index 0000000..7f10041 --- /dev/null +++ b/drivers/watchdog/pm8916_wdt.c @@ -0,0 +1,211 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define PON_INT_RT_STS 0x10 +#define PMIC_WD_BARK_STS_BIT BIT(6) + +#define PON_PMIC_WD_RESET_S1_TIMER 0x54 +#define PON_PMIC_WD_RESET_S2_TIMER 0x55 + +#define PON_PMIC_WD_RESET_S2_CTL 0x56 +#define RESET_TYPE_WARM 0x01 +#define RESET_TYPE_SHUTDOWN 0x04 +#define RESET_TYPE_HARD 0x07 + +#define PON_PMIC_WD_RESET_S2_CTL2 0x57 +#define S2_RESET_EN_BIT BIT(7) + +#define PON_PMIC_WD_RESET_PET 0x58 +#define WATCHDOG_PET_BIT BIT(0) + +#define PM8916_WDT_DEFAULT_TIMEOUT 32 +#define PM8916_WDT_MIN_TIMEOUT 1 +#define PM8916_WDT_MAX_TIMEOUT 127 + +struct pm8916_wdt { + struct regmap *regmap; + struct watchdog_device wdev; + u32 baseaddr; +}; + +static int pm8916_wdt_start(struct watchdog_device *wdev) +{ + struct pm8916_wdt *wdt = watchdog_get_drvdata(wdev); + + return regmap_update_bits(wdt->regmap, + wdt->baseaddr + PON_PMIC_WD_RESET_S2_CTL2, + S2_RESET_EN_BIT, S2_RESET_EN_BIT); +} + +static int pm8916_wdt_stop(struct watchdog_device *wdev) +{ + struct pm8916_wdt *wdt = watchdog_get_drvdata(wdev); + + return regmap_update_bits(wdt->regmap, + wdt->baseaddr + PON_PMIC_WD_RESET_S2_CTL2, + S2_RESET_EN_BIT, 0); +} + +static int pm8916_wdt_ping(struct watchdog_device *wdev) +{ + struct pm8916_wdt *wdt = watchdog_get_drvdata(wdev); + + return regmap_update_bits(wdt->regmap, + wdt->baseaddr + PON_PMIC_WD_RESET_PET, + WATCHDOG_PET_BIT, WATCHDOG_PET_BIT); +} + +static int pm8916_wdt_configure_timers(struct watchdog_device *wdev) +{ + struct pm8916_wdt *wdt = watchdog_get_drvdata(wdev); + int err; + + err = regmap_write(wdt->regmap, + wdt->baseaddr + PON_PMIC_WD_RESET_S1_TIMER, + wdev->timeout - wdev->pretimeout); + if (err) + return err; + + return regmap_write(wdt->regmap, + wdt->baseaddr + PON_PMIC_WD_RESET_S2_TIMER, + wdev->pretimeout); +} + +static int pm8916_wdt_set_timeout(struct watchdog_device *wdev, + unsigned int timeout) +{ + wdev->timeout = timeout; + + return pm8916_wdt_configure_timers(wdev); +} + +static int pm8916_wdt_set_pretimeout(struct watchdog_device *wdev, + unsigned int pretimeout) +{ + wdev->pretimeout = pretimeout; + + return pm8916_wdt_configure_timers(wdev); +} + +static irqreturn_t pm8916_wdt_isr(int irq, void *arg) +{ + struct pm8916_wdt *wdt = arg; + int err, sts; + + err = regmap_read(wdt->regmap, wdt->baseaddr + PON_INT_RT_STS, &sts); + if (err) + return IRQ_HANDLED; + + if (sts & PMIC_WD_BARK_STS_BIT) + watchdog_notify_pretimeout(&wdt->wdev); + + return IRQ_HANDLED; +} + +static const struct watchdog_info pm8916_wdt_ident = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, + .identity = "QCOM PM8916 PON WDT", +}; + +static const struct watchdog_info pm8916_wdt_pt_ident = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE | + WDIOF_PRETIMEOUT, + .identity = "QCOM PM8916 PON WDT", +}; + +static const struct watchdog_ops pm8916_wdt_ops = { + .owner = THIS_MODULE, + .start = pm8916_wdt_start, + .stop = pm8916_wdt_stop, + .ping = pm8916_wdt_ping, + .set_timeout = pm8916_wdt_set_timeout, + .set_pretimeout = pm8916_wdt_set_pretimeout, +}; + +static int pm8916_wdt_probe(struct platform_device *pdev) +{ + struct pm8916_wdt *wdt; + struct device *parent; + int err, irq; + + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL); + if (!wdt) + return -ENOMEM; + + parent = pdev->dev.parent; + + /* + * The pm8916-pon-wdt is a child of the pon device, which is a child + * of the pm8916 mfd device. We want access to the pm8916 registers. + * Retrieve regmap from pm8916 (parent->parent) and base address + * from pm8916-pon (pon). + */ + wdt->regmap = dev_get_regmap(parent->parent, NULL); + if (!wdt->regmap) { + dev_err(&pdev->dev, "failed to locate regmap\n"); + return -ENODEV; + } + + err = device_property_read_u32(parent, "reg", &wdt->baseaddr); + if (err) { + dev_err(&pdev->dev, "failed to get pm8916-pon address\n"); + return err; + } + + irq = platform_get_irq(pdev, 0); + if (irq > 0) { + if (devm_request_irq(&pdev->dev, irq, pm8916_wdt_isr, 0, + "pm8916_wdt", wdt)) + irq = 0; + } + + /* Configure watchdog to hard-reset mode */ + err = regmap_write(wdt->regmap, + wdt->baseaddr + PON_PMIC_WD_RESET_S2_CTL, + RESET_TYPE_HARD); + if (err) { + dev_err(&pdev->dev, "failed configure watchdog\n"); + return err; + } + + wdt->wdev.info = (irq > 0) ? &pm8916_wdt_pt_ident : &pm8916_wdt_ident, + wdt->wdev.ops = &pm8916_wdt_ops, + wdt->wdev.parent = &pdev->dev; + wdt->wdev.min_timeout = PM8916_WDT_MIN_TIMEOUT; + wdt->wdev.max_timeout = PM8916_WDT_MAX_TIMEOUT; + wdt->wdev.timeout = PM8916_WDT_DEFAULT_TIMEOUT; + wdt->wdev.pretimeout = 0; + watchdog_set_drvdata(&wdt->wdev, wdt); + + watchdog_init_timeout(&wdt->wdev, 0, &pdev->dev); + pm8916_wdt_configure_timers(&wdt->wdev); + + return devm_watchdog_register_device(&pdev->dev, &wdt->wdev); +} + +static const struct of_device_id pm8916_wdt_id_table[] = { + { .compatible = "qcom,pm8916-wdt" }, + { } +}; +MODULE_DEVICE_TABLE(of, pm8916_wdt_id_table); + +static struct platform_driver pm8916_wdt_driver = { + .probe = pm8916_wdt_probe, + .driver = { + .name = "pm8916-wdt", + .of_match_table = of_match_ptr(pm8916_wdt_id_table), + }, +}; +module_platform_driver(pm8916_wdt_driver); + +MODULE_AUTHOR("Loic Poulain "); +MODULE_DESCRIPTION("Qualcomm pm8916 watchdog driver"); +MODULE_LICENSE("GPL v2"); -- 2.7.4