From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932236AbbJ3R2R (ORCPT ); Fri, 30 Oct 2015 13:28:17 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:38343 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751704AbbJ3R2P (ORCPT ); Fri, 30 Oct 2015 13:28:15 -0400 Date: Fri, 30 Oct 2015 17:28:07 +0000 From: Lee Jones To: Damien Riegel Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-watchdog@vger.kernel.org, shawnguo@kernel.org, kernel@pengutronix.de, wim@iguana.be, robh+dt@kernel.org, sameo@linux.intel.com, dinh.linux@gmail.com, linux@roeck-us.net, kernel@savoirfairelinux.com Subject: Re: [PATCH v2 3/5] watchdog: ts4800: add driver for TS-4800 watchdog Message-ID: <20151030172807.GD4058@x1> References: <1446150450-22093-1-git-send-email-damien.riegel@savoirfairelinux.com> <1446150450-22093-4-git-send-email-damien.riegel@savoirfairelinux.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1446150450-22093-4-git-send-email-damien.riegel@savoirfairelinux.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Where is your change-log? I have no idea what the intention of this patch is. > Signed-off-by: Damien Riegel > --- > .../devicetree/bindings/mfd/ts4800-syscon.txt | 8 + > .../devicetree/bindings/watchdog/ts4800-wdt.txt | 12 ++ These should be in a seperate patch. > drivers/mfd/Kconfig | 1 + > drivers/mfd/ts4800-syscon.c | 13 +- > drivers/watchdog/Kconfig | 10 + > drivers/watchdog/Makefile | 1 + > drivers/watchdog/ts4800_wdt.c | 216 +++++++++++++++++++++ > 7 files changed, 260 insertions(+), 1 deletion(-) > create mode 100644 Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt > create mode 100644 drivers/watchdog/ts4800_wdt.c > > diff --git a/Documentation/devicetree/bindings/mfd/ts4800-syscon.txt b/Documentation/devicetree/bindings/mfd/ts4800-syscon.txt > index 8dbc12c..8c0fd1d 100644 > --- a/Documentation/devicetree/bindings/mfd/ts4800-syscon.txt > +++ b/Documentation/devicetree/bindings/mfd/ts4800-syscon.txt > @@ -4,9 +4,17 @@ Required properties: > - compatible : must be "ts,ts4800-syscon" > - reg : physical base address and length of memory mapped region > > +The driver exposes following subdevices: > +- a watchdog: see ../watchdog/ts4800-wdt.txt > + > Example: > > syscon@b0010000 { > compatible = "ts,ts4800-syscon"; > reg = <0xb0010000 0x3d>; > + > + wdt@e { > + compatible = "ts,ts4800-wdt"; > + offset = <0xe>; > + }; > }; > diff --git a/Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt b/Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt > new file mode 100644 > index 0000000..a9305c2 > --- /dev/null > +++ b/Documentation/devicetree/bindings/watchdog/ts4800-wdt.txt > @@ -0,0 +1,12 @@ > +Technologic Systems Watchdog > + > +Required properties: > +- compatible : must be "ts,ts4800-wdt" > +- offset : offset of the feed register from syscon base > + > +Example: > + > +wdt1: wdt@b0010000 { > + compatible = "ts,ts4800-wdt"; > + offset = <0xe>; > +}; > diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig > index 8f03dce..95ba036 100644 > --- a/drivers/mfd/Kconfig > +++ b/drivers/mfd/Kconfig > @@ -1304,6 +1304,7 @@ config MFD_TC6393XB > > config MFD_TS4800_SYSCON > tristate "TS-4800 Syscon Support" > + select MFD_CORE > select REGMAP > select REGMAP_MMIO > help This change is orthogonal and has not place in this patch. > diff --git a/drivers/mfd/ts4800-syscon.c b/drivers/mfd/ts4800-syscon.c > index 1e42e96..03b3b04a 100644 > --- a/drivers/mfd/ts4800-syscon.c > +++ b/drivers/mfd/ts4800-syscon.c > @@ -24,6 +24,13 @@ > #include > > > +static const struct mfd_cell ts4800_syscon_cells[] = { > + { > + .name = "ts4800-watchdog", > + .of_compatible = "ts,ts4800-wdt", > + }, > +}; > + > static const struct regmap_config ts4800_regmap_config = { > .reg_bits = 32, > .reg_stride = 2, > @@ -56,11 +63,15 @@ static int ts4800_syscon_probe(struct platform_device *pdev) > > platform_set_drvdata(pdev, syscon); > > - return 0; > + return mfd_add_devices(&pdev->dev, -1, ts4800_syscon_cells, > + ARRAY_SIZE(ts4800_syscon_cells), > + NULL, 0, NULL); > } > > static int ts4800_syscon_remove(struct platform_device *pdev) > { > + mfd_remove_devices(&pdev->dev); > + > return 0; > } > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index 241fafd..aaa42b8 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -417,6 +417,16 @@ config NUC900_WATCHDOG > To compile this driver as a module, choose M here: the > module will be called nuc900_wdt. > > +config TS4800_WATCHDOG > + tristate "TS-4800 Watchdog" > + depends on OF > + depends on MFD_TS4800_SYSCON > + select WATCHDOG_CORE > + help > + Technologic Systems TS-4800 has watchdog timer implemented in > + an external FPGA. Say Y here if you want to support for the > + watchdog timer on TS-4800 board. > + > config TS72XX_WATCHDOG > tristate "TS-72XX SBC Watchdog" > depends on MACH_TS72XX > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index 59ea9a1..435fc93 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -52,6 +52,7 @@ obj-$(CONFIG_RN5T618_WATCHDOG) += rn5t618_wdt.o > obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o > obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o > obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o > +obj-$(CONFIG_TS4800_WATCHDOG) += ts4800_wdt.o > obj-$(CONFIG_TS72XX_WATCHDOG) += ts72xx_wdt.o > obj-$(CONFIG_IMX2_WDT) += imx2_wdt.o > obj-$(CONFIG_UX500_WATCHDOG) += ux500_wdt.o > diff --git a/drivers/watchdog/ts4800_wdt.c b/drivers/watchdog/ts4800_wdt.c > new file mode 100644 > index 0000000..9b9e638 > --- /dev/null > +++ b/drivers/watchdog/ts4800_wdt.c > @@ -0,0 +1,216 @@ > +/* > + * ts4800_wdt.c - Watchdog driver for TS-4800 based boards > + * > + * Copyright (c) 2015 - Savoir-faire Linux > + * > + * This file is licensed under the terms of the GNU General Public > + * License version 2. This program is licensed "as is" without any > + * warranty of any kind, whether express or implied. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +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) ")"); > + > + > +/* possible feed values */ > +#define TS4800_WDT_FEED_2S 0x1 > +#define TS4800_WDT_FEED_10S 0x2 > +#define TS4800_WDT_DISABLE 0x3 > + > + > +struct ts4800_wdt { > + struct watchdog_device wdd; > + struct regmap *regmap; > + u32 feed_offset; > + u16 feed_val; > +}; > + > +/* > + * TS-4800 supports the following timeout values: > + * > + * value desc > + * --------------------- > + * 0 feed for 338ms > + * 1 feed for 2.706s > + * 2 feed for 10.824s > + * 3 disable watchdog > + * > + * Keep the regmap/timeout map ordered by timeout > + */ > +static const struct { > + const int timeout; > + const int regval; > +} ts4800_wdt_map[] = { > + { 2, TS4800_WDT_FEED_2S }, > + { 10, TS4800_WDT_FEED_10S }, > +}; > + > +static int timeout_to_regval(struct watchdog_device *wdd, int new_timeout) > +{ > + int i; > + > + new_timeout = clamp_val(new_timeout, > + wdd->min_timeout, wdd->max_timeout); > + > + for (i = 0; i < ARRAY_SIZE(ts4800_wdt_map); i++) { > + if (ts4800_wdt_map[i].timeout >= new_timeout) > + return ts4800_wdt_map[i].timeout; > + } > + > + return -EINVAL; > +} > + > +static void ts4800_write_feed(struct ts4800_wdt *wdt, u16 val) > +{ > + regmap_write(wdt->regmap, wdt->feed_offset, val); > +} > + > +static int ts4800_wdt_ping(struct watchdog_device *wdd) > +{ > + struct ts4800_wdt *wdt = watchdog_get_drvdata(wdd); > + > + ts4800_write_feed(wdt, wdt->feed_val); > + return 0; > +} > + > +static int ts4800_wdt_stop(struct watchdog_device *wdd) > +{ > + struct ts4800_wdt *wdt = watchdog_get_drvdata(wdd); > + > + ts4800_write_feed(wdt, TS4800_WDT_DISABLE); > + return 0; > +} > + > +static int ts4800_wdt_set_timeout(struct watchdog_device *wdd, > + unsigned int new_timeout) > +{ > + struct ts4800_wdt *wdt = watchdog_get_drvdata(wdd); > + int val = timeout_to_regval(wdd, new_timeout); > + > + if (val < 0) > + return val; > + > + wdt->feed_val = (u16) val; > + > + return 0; > +} > + > +static const struct watchdog_ops ts4800_wdt_ops = { > + .owner = THIS_MODULE, > + /* > + * pinging the watchdog enables it, so use same function > + * for pinging and starting the watchdog > + */ > + .start = ts4800_wdt_ping, > + .stop = ts4800_wdt_stop, > + .ping = ts4800_wdt_ping, > + .set_timeout = ts4800_wdt_set_timeout, > +}; > + > +static const struct watchdog_info ts4800_wdt_info = { > + .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, > + .identity = "TS-4800 Watchdog", > +}; > + > +static int ts4800_wdt_probe(struct platform_device *pdev) > +{ > + int max_timeout_index = ARRAY_SIZE(ts4800_wdt_map) - 1; > + struct device_node *np = pdev->dev.of_node; > + struct ts4800_syscon *syscon; > + struct watchdog_device *wdd; > + struct ts4800_wdt *wdt; > + u32 offset; > + int ret; > + > + ret = of_property_read_u32(np, "offset", &offset); > + if (ret) { > + dev_err(&pdev->dev, "An offset must be provided\n"); > + return -EINVAL; > + } > + > + /* allocate memory for watchdog struct */ > + wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL); > + if (!wdt) > + return -ENOMEM; > + > + /* set regmap and offset to know where to write */ > + syscon = dev_get_drvdata(pdev->dev.parent); > + wdt->regmap = syscon->regmap; > + wdt->feed_offset = offset; > + > + /* Initialize struct watchdog_device */ > + wdd = &wdt->wdd; > + wdd->info = &ts4800_wdt_info; > + wdd->ops = &ts4800_wdt_ops; > + wdd->min_timeout = ts4800_wdt_map[0].timeout; > + wdd->max_timeout = ts4800_wdt_map[max_timeout_index].timeout; > + wdd->timeout = wdd->max_timeout; > + wdt->feed_val = ts4800_wdt_map[max_timeout_index].regval; > + > + watchdog_set_drvdata(wdd, wdt); > + watchdog_set_nowayout(wdd, nowayout); > + > + /* > + * Must be called after watchdog_set_drvdata to dereference a valid > + * pointer. The feed register is write-only, so it is not possible to > + * determine if watchdog is already started or not. Disable it to be in > + * a known state. > + */ > + ts4800_wdt_stop(wdd); > + > + ret = watchdog_register_device(wdd); > + if (ret) { > + dev_err(&pdev->dev, > + "failed to register watchdog device\n"); > + return ret; > + } > + > + platform_set_drvdata(pdev, wdt); > + > + dev_info(&pdev->dev, > + "initialized (timeout = %d sec, nowayout = %d)\n", > + wdd->timeout, nowayout); > + > + return 0; > +} > + > +static int ts4800_wdt_remove(struct platform_device *pdev) > +{ > + struct ts4800_wdt *wdt = platform_get_drvdata(pdev); > + > + watchdog_unregister_device(&wdt->wdd); > + > + return 0; > +} > + > +static const struct of_device_id ts4800_wdt_of_match[] = { > + { .compatible = "ts,ts4800-wdt", }, > + { }, > +}; > +MODULE_DEVICE_TABLE(of, ts4800_wdt_of_match); > + > +static struct platform_driver ts4800_wdt_driver = { > + .probe = ts4800_wdt_probe, > + .remove = ts4800_wdt_remove, > + .driver = { > + .name = "ts4800_wdt", > + .of_match_table = ts4800_wdt_of_match, > + }, > +}; > + > +module_platform_driver(ts4800_wdt_driver); > + > +MODULE_AUTHOR("Damien Riegel "); > +MODULE_LICENSE("GPL"); > +MODULE_ALIAS("platform:ts4800_wdt"); -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog