| Message ID | 1369499297-855-1-git-send-email-carlo.caione@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, May 25, 2013 at 06:28:17PM +0200, Carlo Caione wrote: > This patch adds the driver for the watchdog found in the Allwinner A10 and > A13 SoCs. It has DT-support and uses the new watchdog framework. > > Signed-off-by: Carlo Caione <carlo.caione@gmail.com> > --- > drivers/watchdog/Kconfig | 10 ++ > drivers/watchdog/Makefile | 1 + > drivers/watchdog/sunxi_wdt.c | 226 +++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 237 insertions(+) > create mode 100644 drivers/watchdog/sunxi_wdt.c > > diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig > index e89fc31..8ad2238 100644 > --- a/drivers/watchdog/Kconfig > +++ b/drivers/watchdog/Kconfig > @@ -299,6 +299,16 @@ config ORION_WATCHDOG > To compile this driver as a module, choose M here: the > module will be called orion_wdt. > > +config SUNXI_WATCHDOG > + tristate "Allwinner SoCs watchdog support" > + depends on ARCH_SUNXI > + select WATCHDOG_CORE > + help > + Say Y here to include support for the watchdog timer > + in Allwinner SoCs. > + To compile this driver as a module, choose M here: the > + module will be called sunxi_wdt. > + > config COH901327_WATCHDOG > bool "ST-Ericsson COH 901 327 watchdog" > depends on ARCH_U300 > diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile > index a300b94..5012d5f 100644 > --- a/drivers/watchdog/Makefile > +++ b/drivers/watchdog/Makefile > @@ -47,6 +47,7 @@ obj-$(CONFIG_PNX4008_WATCHDOG) += pnx4008_wdt.o > obj-$(CONFIG_IOP_WATCHDOG) += iop_wdt.o > obj-$(CONFIG_DAVINCI_WATCHDOG) += davinci_wdt.o > obj-$(CONFIG_ORION_WATCHDOG) += orion_wdt.o > +obj-$(CONFIG_SUNXI_WATCHDOG) += sunxi_wdt.o > obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o > obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o > obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o > diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c > new file mode 100644 > index 0000000..57983c0 > --- /dev/null > +++ b/drivers/watchdog/sunxi_wdt.c > @@ -0,0 +1,226 @@ > +/* > + * sunxi Watchdog Driver > + * > + * Copyright (c) 2013 Carlo Caione > + * 2012 Henrik Nordstrom > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License > + * as published by the Free Software Foundation; either version > + * 2 of the License, or (at your option) any later version. > + * > + * Based on xen_wdt.c > + * (c) Copyright 2010 Novell, Inc. > + */ > + > +#include <linux/clk.h> > +#include <linux/err.h> > +#include <linux/init.h> > +#include <linux/io.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/moduleparam.h> > +#include <linux/of.h> > +#include <linux/of_address.h> > +#include <linux/platform_device.h> > +#include <linux/types.h> > +#include <linux/watchdog.h> > + > +#define WDT_MAX_TIMEOUT 16 > +#define WDT_MIN_TIMEOUT 1 > +#define WDT_MODE_TIMEOUT(n) ((n) << 3) > +#define WDT_TIMEOUT_MASK WDT_MODE_TIMEOUT(0x0F) > + > +#define WDT_CTRL 0x00 > +#define WDT_CTRL_RELOAD ((1 << 0) | (0x0a57 << 1)) > + > +#define WDT_MODE 0x04 > +#define WDT_MODE_EN (1 << 0) > +#define WDT_MODE_RST_EN (1 << 1) > + > +#define DRV_NAME "sunxi-wdt" > +#define DRV_VERSION "1.0" > + > +static bool nowayout = WATCHDOG_NOWAYOUT; > +static int heartbeat = WDT_MAX_TIMEOUT; > + > +/* > + * wdt_timeout_map maps the watchdog timer interval value in seconds to > + * the value of the register WDT_MODE bit 3:6 > + * > + * [timeout seconds] = register value > + * > + */ > + > +static const int wdt_timeout_map[] = { > + [1] = 0b0001, /* 1s */ > + [2] = 0b0010, /* 2s */ > + [3] = 0b0011, /* 3s */ > + [4] = 0b0100, /* 4s */ > + [5] = 0b0101, /* 5s */ > + [6] = 0b0110, /* 6s */ > + [8] = 0b0111, /* 8s */ > + [10] = 0b1000, /* 10s */ > + [12] = 0b1001, /* 12s */ > + [14] = 0b1010, /* 14s */ > + [16] = 0b1011, /* 16s */ > +}; > + > +static int sunxi_wdt_ping(struct watchdog_device *sunxi_wdt_dev) > +{ > + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); > + > + iowrite32(WDT_CTRL_RELOAD, wdt_base + WDT_CTRL); > + > + return 0; > +} > + > +static int sunxi_wdt_set_timeout(struct watchdog_device *sunxi_wdt_dev, > + unsigned int timeout) > +{ > + u32 reg; > + int ret = 0; > + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); > + > + if ((timeout > WDT_MAX_TIMEOUT) || (0 == wdt_timeout_map[timeout])) { While understand I do that Yoda programming in fashion is, never accept I would. Mantainer differently may think, though. Extra ( ) only confusing for me is too and no value it adds. But seriously, I think it is not a good idea to expect the user to find valid timeouts. I think it would be much better to select the closest (larger) timeout if there is no exact match. > + ret = -EINVAL; > + goto exit; > + } > + > + sunxi_wdt_dev->timeout = timeout; > + > + reg = ioread32(wdt_base + WDT_MODE); > + reg &= ~(WDT_TIMEOUT_MASK); Another unnecessary ( ) > + reg |= WDT_MODE_TIMEOUT(wdt_timeout_map[sunxi_wdt_dev->timeout]); > + iowrite32(reg, wdt_base + WDT_MODE); > + > + sunxi_wdt_ping(sunxi_wdt_dev); > + > +exit: > + return ret; > +} > + > +static int sunxi_wdt_stop(struct watchdog_device *sunxi_wdt_dev) > +{ > + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); > + > + iowrite32(0, wdt_base + WDT_MODE); > + > + return 0; > +} > + > +static int sunxi_wdt_start(struct watchdog_device *sunxi_wdt_dev) > +{ > + u32 reg; > + int ret = 0; > + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); > + > + ret = sunxi_wdt_set_timeout(sunxi_wdt_dev, sunxi_wdt_dev->timeout); > + if (ret < 0) > + goto exit; > + > + reg = ioread32(wdt_base + WDT_MODE); > + reg |= (WDT_MODE_RST_EN | WDT_MODE_EN); > + iowrite32(reg, wdt_base + WDT_MODE); > + > +exit: > + return ret; > +} > + > +static const struct watchdog_info sunxi_wdt_info = { > + .identity = DRV_NAME, > + .options = WDIOF_SETTIMEOUT | > + WDIOF_KEEPALIVEPING | > + WDIOF_MAGICCLOSE, > +}; > + > +static const struct watchdog_ops sunxi_wdt_ops = { > + .owner = THIS_MODULE, > + .start = sunxi_wdt_start, > + .stop = sunxi_wdt_stop, > + .ping = sunxi_wdt_ping, > + .set_timeout = sunxi_wdt_set_timeout, > +}; > + > +static struct watchdog_device sunxi_wdt_dev = { > + .info = &sunxi_wdt_info, > + .ops = &sunxi_wdt_ops, > + .timeout = WDT_MAX_TIMEOUT, > + .max_timeout = WDT_MAX_TIMEOUT, > + .min_timeout = WDT_MIN_TIMEOUT, > +}; > + Wonder what happens if one instantiates this driver twice ? > +static int __init sunxi_wdt_probe(struct platform_device *pdev) > +{ > + int err; > + struct resource *res; > + void __iomem *wdt_base; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + wdt_base = devm_ioremap_resource(&pdev->dev, res); > + if (IS_ERR(wdt_base)) { > + err = PTR_ERR(wdt_base); > + goto error_mem_out; Just return the error. No need for a goto to a return statement. > + } > + > + sunxi_wdt_dev.parent = &pdev->dev; > + watchdog_init_timeout(&sunxi_wdt_dev, heartbeat, &pdev->dev); > + watchdog_set_nowayout(&sunxi_wdt_dev, nowayout); > + > + err = watchdog_register_device(&sunxi_wdt_dev); > + if (unlikely(err)) > + goto error_wdt; > + > + watchdog_set_drvdata(&sunxi_wdt_dev, wdt_base); > + > + dev_info(&pdev->dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)", > + sunxi_wdt_dev.timeout, nowayout); > + return 0; > + > +error_wdt: > + iounmap(wdt_base); This is no longer needed (and wrong). You'll notice that the entire error path is no longer needed, which is the whole point of having devm_ functions. > +error_mem_out: > + return err; > +} > + > +static int __exit sunxi_wdt_remove(struct platform_device *pdev) > +{ > + void __iomem *wdt_base = watchdog_get_drvdata(&sunxi_wdt_dev); > + > + sunxi_wdt_stop(&sunxi_wdt_dev); Even if nowayout is true ? Wonder how other drivers handle this. > + watchdog_unregister_device(&sunxi_wdt_dev); > + iounmap(wdt_base); Same as above. > + > + return 0; > +} > + > +static const struct of_device_id sunxi_wdt_dt_ids[] = { > + { .compatible = "allwinner,sun4i-wdt" }, > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids); > + > +static struct platform_driver sunxi_wdt_driver = { > + .probe = sunxi_wdt_probe, > + .remove = sunxi_wdt_remove, > + .driver = { > + .owner = THIS_MODULE, > + .name = DRV_NAME, > + .of_match_table = of_match_ptr(sunxi_wdt_dt_ids) > + }, > +}; > + > +module_platform_driver(sunxi_wdt_driver); > + > +module_param(heartbeat, int, 0); > +MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds"); > + > +module_param(nowayout, bool, 0); > +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " > + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); > + > +MODULE_LICENSE("GPL"); > +MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>"); > +MODULE_AUTHOR("Henrik Nordstrom <henrik@henriknordstrom.net>"); > +MODULE_DESCRIPTION("sunxi WatchDog Timer Driver"); > +MODULE_VERSION(DRV_VERSION); > -- > 1.8.2.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html >
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index e89fc31..8ad2238 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -299,6 +299,16 @@ config ORION_WATCHDOG To compile this driver as a module, choose M here: the module will be called orion_wdt. +config SUNXI_WATCHDOG + tristate "Allwinner SoCs watchdog support" + depends on ARCH_SUNXI + select WATCHDOG_CORE + help + Say Y here to include support for the watchdog timer + in Allwinner SoCs. + To compile this driver as a module, choose M here: the + module will be called sunxi_wdt. + config COH901327_WATCHDOG bool "ST-Ericsson COH 901 327 watchdog" depends on ARCH_U300 diff --git a/drivers/watchdog/Makefile b/drivers/watchdog/Makefile index a300b94..5012d5f 100644 --- a/drivers/watchdog/Makefile +++ b/drivers/watchdog/Makefile @@ -47,6 +47,7 @@ obj-$(CONFIG_PNX4008_WATCHDOG) += pnx4008_wdt.o obj-$(CONFIG_IOP_WATCHDOG) += iop_wdt.o obj-$(CONFIG_DAVINCI_WATCHDOG) += davinci_wdt.o obj-$(CONFIG_ORION_WATCHDOG) += orion_wdt.o +obj-$(CONFIG_SUNXI_WATCHDOG) += sunxi_wdt.o obj-$(CONFIG_COH901327_WATCHDOG) += coh901327_wdt.o obj-$(CONFIG_STMP3XXX_RTC_WATCHDOG) += stmp3xxx_rtc_wdt.o obj-$(CONFIG_NUC900_WATCHDOG) += nuc900_wdt.o diff --git a/drivers/watchdog/sunxi_wdt.c b/drivers/watchdog/sunxi_wdt.c new file mode 100644 index 0000000..57983c0 --- /dev/null +++ b/drivers/watchdog/sunxi_wdt.c @@ -0,0 +1,226 @@ +/* + * sunxi Watchdog Driver + * + * Copyright (c) 2013 Carlo Caione + * 2012 Henrik Nordstrom + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * Based on xen_wdt.c + * (c) Copyright 2010 Novell, Inc. + */ + +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/types.h> +#include <linux/watchdog.h> + +#define WDT_MAX_TIMEOUT 16 +#define WDT_MIN_TIMEOUT 1 +#define WDT_MODE_TIMEOUT(n) ((n) << 3) +#define WDT_TIMEOUT_MASK WDT_MODE_TIMEOUT(0x0F) + +#define WDT_CTRL 0x00 +#define WDT_CTRL_RELOAD ((1 << 0) | (0x0a57 << 1)) + +#define WDT_MODE 0x04 +#define WDT_MODE_EN (1 << 0) +#define WDT_MODE_RST_EN (1 << 1) + +#define DRV_NAME "sunxi-wdt" +#define DRV_VERSION "1.0" + +static bool nowayout = WATCHDOG_NOWAYOUT; +static int heartbeat = WDT_MAX_TIMEOUT; + +/* + * wdt_timeout_map maps the watchdog timer interval value in seconds to + * the value of the register WDT_MODE bit 3:6 + * + * [timeout seconds] = register value + * + */ + +static const int wdt_timeout_map[] = { + [1] = 0b0001, /* 1s */ + [2] = 0b0010, /* 2s */ + [3] = 0b0011, /* 3s */ + [4] = 0b0100, /* 4s */ + [5] = 0b0101, /* 5s */ + [6] = 0b0110, /* 6s */ + [8] = 0b0111, /* 8s */ + [10] = 0b1000, /* 10s */ + [12] = 0b1001, /* 12s */ + [14] = 0b1010, /* 14s */ + [16] = 0b1011, /* 16s */ +}; + +static int sunxi_wdt_ping(struct watchdog_device *sunxi_wdt_dev) +{ + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); + + iowrite32(WDT_CTRL_RELOAD, wdt_base + WDT_CTRL); + + return 0; +} + +static int sunxi_wdt_set_timeout(struct watchdog_device *sunxi_wdt_dev, + unsigned int timeout) +{ + u32 reg; + int ret = 0; + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); + + if ((timeout > WDT_MAX_TIMEOUT) || (0 == wdt_timeout_map[timeout])) { + ret = -EINVAL; + goto exit; + } + + sunxi_wdt_dev->timeout = timeout; + + reg = ioread32(wdt_base + WDT_MODE); + reg &= ~(WDT_TIMEOUT_MASK); + reg |= WDT_MODE_TIMEOUT(wdt_timeout_map[sunxi_wdt_dev->timeout]); + iowrite32(reg, wdt_base + WDT_MODE); + + sunxi_wdt_ping(sunxi_wdt_dev); + +exit: + return ret; +} + +static int sunxi_wdt_stop(struct watchdog_device *sunxi_wdt_dev) +{ + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); + + iowrite32(0, wdt_base + WDT_MODE); + + return 0; +} + +static int sunxi_wdt_start(struct watchdog_device *sunxi_wdt_dev) +{ + u32 reg; + int ret = 0; + void __iomem *wdt_base = watchdog_get_drvdata(sunxi_wdt_dev); + + ret = sunxi_wdt_set_timeout(sunxi_wdt_dev, sunxi_wdt_dev->timeout); + if (ret < 0) + goto exit; + + reg = ioread32(wdt_base + WDT_MODE); + reg |= (WDT_MODE_RST_EN | WDT_MODE_EN); + iowrite32(reg, wdt_base + WDT_MODE); + +exit: + return ret; +} + +static const struct watchdog_info sunxi_wdt_info = { + .identity = DRV_NAME, + .options = WDIOF_SETTIMEOUT | + WDIOF_KEEPALIVEPING | + WDIOF_MAGICCLOSE, +}; + +static const struct watchdog_ops sunxi_wdt_ops = { + .owner = THIS_MODULE, + .start = sunxi_wdt_start, + .stop = sunxi_wdt_stop, + .ping = sunxi_wdt_ping, + .set_timeout = sunxi_wdt_set_timeout, +}; + +static struct watchdog_device sunxi_wdt_dev = { + .info = &sunxi_wdt_info, + .ops = &sunxi_wdt_ops, + .timeout = WDT_MAX_TIMEOUT, + .max_timeout = WDT_MAX_TIMEOUT, + .min_timeout = WDT_MIN_TIMEOUT, +}; + +static int __init sunxi_wdt_probe(struct platform_device *pdev) +{ + int err; + struct resource *res; + void __iomem *wdt_base; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + wdt_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(wdt_base)) { + err = PTR_ERR(wdt_base); + goto error_mem_out; + } + + sunxi_wdt_dev.parent = &pdev->dev; + watchdog_init_timeout(&sunxi_wdt_dev, heartbeat, &pdev->dev); + watchdog_set_nowayout(&sunxi_wdt_dev, nowayout); + + err = watchdog_register_device(&sunxi_wdt_dev); + if (unlikely(err)) + goto error_wdt; + + watchdog_set_drvdata(&sunxi_wdt_dev, wdt_base); + + dev_info(&pdev->dev, "Watchdog enabled (heartbeat=%d sec, nowayout=%d)", + sunxi_wdt_dev.timeout, nowayout); + return 0; + +error_wdt: + iounmap(wdt_base); +error_mem_out: + return err; +} + +static int __exit sunxi_wdt_remove(struct platform_device *pdev) +{ + void __iomem *wdt_base = watchdog_get_drvdata(&sunxi_wdt_dev); + + sunxi_wdt_stop(&sunxi_wdt_dev); + watchdog_unregister_device(&sunxi_wdt_dev); + iounmap(wdt_base); + + return 0; +} + +static const struct of_device_id sunxi_wdt_dt_ids[] = { + { .compatible = "allwinner,sun4i-wdt" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids); + +static struct platform_driver sunxi_wdt_driver = { + .probe = sunxi_wdt_probe, + .remove = sunxi_wdt_remove, + .driver = { + .owner = THIS_MODULE, + .name = DRV_NAME, + .of_match_table = of_match_ptr(sunxi_wdt_dt_ids) + }, +}; + +module_platform_driver(sunxi_wdt_driver); + +module_param(heartbeat, int, 0); +MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds"); + +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " + "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Carlo Caione <carlo.caione@gmail.com>"); +MODULE_AUTHOR("Henrik Nordstrom <henrik@henriknordstrom.net>"); +MODULE_DESCRIPTION("sunxi WatchDog Timer Driver"); +MODULE_VERSION(DRV_VERSION);
This patch adds the driver for the watchdog found in the Allwinner A10 and A13 SoCs. It has DT-support and uses the new watchdog framework. Signed-off-by: Carlo Caione <carlo.caione@gmail.com> --- drivers/watchdog/Kconfig | 10 ++ drivers/watchdog/Makefile | 1 + drivers/watchdog/sunxi_wdt.c | 226 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 237 insertions(+) create mode 100644 drivers/watchdog/sunxi_wdt.c