| Message ID | 1412119508-22864-2-git-send-email-fkan@apm.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
On 09/30/2014 04:25 PM, Feng Kan wrote: > Add a generic SYSCON register mapped reset mechanism. > > Signed-off-by: Feng Kan <fkan@apm.com> > --- > drivers/power/reset/Kconfig | 5 ++ > drivers/power/reset/Makefile | 1 + > drivers/power/reset/syscon-reboot.c | 96 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 102 insertions(+) > create mode 100644 drivers/power/reset/syscon-reboot.c > > diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig > index 1915dde..a863fa1 100644 > --- a/drivers/power/reset/Kconfig > +++ b/drivers/power/reset/Kconfig > @@ -143,4 +143,9 @@ config POWER_RESET_KEYSTONE > help > Reboot support for the KEYSTONE SoCs. > > +config POWER_RESET_SYSCON > + bool "Generic SYSCON regmap reset driver" > + depends on POWER_RESET && MFD_SYSCON && OF Other drivers have select MFD_SYSCON > + help > + Reboot support for generic SYSCON mapped register reset. > endif > diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile > index 01e401d..76ce1c5 100644 > --- a/drivers/power/reset/Makefile > +++ b/drivers/power/reset/Makefile > @@ -16,3 +16,4 @@ obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o > obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o > obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o > obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o > +obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o > diff --git a/drivers/power/reset/syscon-reboot.c b/drivers/power/reset/syscon-reboot.c > new file mode 100644 > index 0000000..948e0ee > --- /dev/null > +++ b/drivers/power/reset/syscon-reboot.c > @@ -0,0 +1,96 @@ > +/* > + * Generic Syscon Reboot Driver > + * > + * Copyright (c) 2013, Applied Micro Circuits Corporation > + * Author: Feng Kan <fkan@apm.com> > + * > + * 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. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > +#include <linux/io.h> > +#include <linux/of_device.h> > +#include <linux/of_address.h> > +#include <linux/platform_device.h> > +#include <linux/notifier.h> alphabetic order of include files ? > +#include <linux/mfd/syscon.h> > +#include <linux/regmap.h> > +#include <linux/reboot.h> > + > +struct syscon_reboot_context { > + struct regmap *map; > + u32 offset; > + u32 mask; > + struct notifier_block restart_handler; > +}; > + > +static struct syscon_reboot_context *syscon_reboot_ctx; > + > +static int syscon_restart_handle(struct notifier_block *this, > + unsigned long mode, void *cmd) > +{ > + struct syscon_reboot_context *ctx = syscon_reboot_ctx; Since restart_handler is part of syscon_reboot_context, you do not need a static variable. You can use struct syscon_reboot_context *ctx = container_of(ctx, struct syscon_reboot_context, restart_handler); instead. > + unsigned long timeout; > + > + /* Issue the reboot */ > + if (ctx->map) > + regmap_write(ctx->map, ctx->offset, ctx->mask); > + The check for ctx->map is not needed. If the restart handler is installed, it will always be valid. > + timeout = jiffies + HZ; > + while (time_before(jiffies, timeout)) > + cpu_relax(); > + jiffies won't work here, and nothing else is expected to happen. Just use mdelay(1000); > + pr_emerg("Unable to restart system\n"); > + return NOTIFY_DONE; > +} > + > +static int syscon_reboot_probe(struct platform_device *pdev) > +{ > + struct syscon_reboot_context *ctx; > + struct device *dev = &pdev->dev; > + int err; > + > + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); > + if (!ctx) > + return -ENOMEM; > + > + ctx->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap"); > + if (IS_ERR(ctx->map)) > + return PTR_ERR(ctx->map); > + > + if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset)) > + return -EINVAL; > + > + if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask)) > + return -EINVAL; > + > + ctx->restart_handler.notifier_call = syscon_restart_handle; > + ctx->restart_handler.priority = 128; > + err = register_restart_handler(&ctx->restart_handler); > + if (err) > + dev_err(dev, "can't register restart notifier (err=%d)\n", err); > + > + syscon_reboot_ctx = ctx; > + > + return 0; > +} > + > +static struct of_device_id syscon_reboot_of_match[] = { > + { .compatible = "syscon-reboot" }, > + {} > +}; > + > +static struct platform_driver syscon_reboot_driver = { > + .probe = syscon_reboot_probe, > + .driver = { > + .name = "syscon-reboot", > + .of_match_table = syscon_reboot_of_match, > + }, > +}; > +module_platform_driver(syscon_reboot_driver); > -- To unsubscribe from this list: send the line "unsubscribe linux-pm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi, On Tue, Sep 30, 2014 at 04:25:03PM -0700, Feng Kan wrote: > Add a generic SYSCON register mapped reset mechanism. > > Signed-off-by: Feng Kan <fkan@apm.com> I have merged the driver and its documentation to battery-2.6.git. This should make it possible for the changes in arch/arm to be merged via ARM maintainers in 3.19. Please fix Guenter's comments in an incremental patch. -- Sebastian
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index 1915dde..a863fa1 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -143,4 +143,9 @@ config POWER_RESET_KEYSTONE help Reboot support for the KEYSTONE SoCs. +config POWER_RESET_SYSCON + bool "Generic SYSCON regmap reset driver" + depends on POWER_RESET && MFD_SYSCON && OF + help + Reboot support for generic SYSCON mapped register reset. endif diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 01e401d..76ce1c5 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -16,3 +16,4 @@ obj-$(CONFIG_POWER_RESET_VERSATILE) += arm-versatile-reboot.o obj-$(CONFIG_POWER_RESET_VEXPRESS) += vexpress-poweroff.o obj-$(CONFIG_POWER_RESET_XGENE) += xgene-reboot.o obj-$(CONFIG_POWER_RESET_KEYSTONE) += keystone-reset.o +obj-$(CONFIG_POWER_RESET_SYSCON) += syscon-reboot.o diff --git a/drivers/power/reset/syscon-reboot.c b/drivers/power/reset/syscon-reboot.c new file mode 100644 index 0000000..948e0ee --- /dev/null +++ b/drivers/power/reset/syscon-reboot.c @@ -0,0 +1,96 @@ +/* + * Generic Syscon Reboot Driver + * + * Copyright (c) 2013, Applied Micro Circuits Corporation + * Author: Feng Kan <fkan@apm.com> + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ +#include <linux/io.h> +#include <linux/of_device.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/notifier.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/reboot.h> + +struct syscon_reboot_context { + struct regmap *map; + u32 offset; + u32 mask; + struct notifier_block restart_handler; +}; + +static struct syscon_reboot_context *syscon_reboot_ctx; + +static int syscon_restart_handle(struct notifier_block *this, + unsigned long mode, void *cmd) +{ + struct syscon_reboot_context *ctx = syscon_reboot_ctx; + unsigned long timeout; + + /* Issue the reboot */ + if (ctx->map) + regmap_write(ctx->map, ctx->offset, ctx->mask); + + timeout = jiffies + HZ; + while (time_before(jiffies, timeout)) + cpu_relax(); + + pr_emerg("Unable to restart system\n"); + return NOTIFY_DONE; +} + +static int syscon_reboot_probe(struct platform_device *pdev) +{ + struct syscon_reboot_context *ctx; + struct device *dev = &pdev->dev; + int err; + + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap"); + if (IS_ERR(ctx->map)) + return PTR_ERR(ctx->map); + + if (of_property_read_u32(pdev->dev.of_node, "offset", &ctx->offset)) + return -EINVAL; + + if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask)) + return -EINVAL; + + ctx->restart_handler.notifier_call = syscon_restart_handle; + ctx->restart_handler.priority = 128; + err = register_restart_handler(&ctx->restart_handler); + if (err) + dev_err(dev, "can't register restart notifier (err=%d)\n", err); + + syscon_reboot_ctx = ctx; + + return 0; +} + +static struct of_device_id syscon_reboot_of_match[] = { + { .compatible = "syscon-reboot" }, + {} +}; + +static struct platform_driver syscon_reboot_driver = { + .probe = syscon_reboot_probe, + .driver = { + .name = "syscon-reboot", + .of_match_table = syscon_reboot_of_match, + }, +}; +module_platform_driver(syscon_reboot_driver);
Add a generic SYSCON register mapped reset mechanism. Signed-off-by: Feng Kan <fkan@apm.com> --- drivers/power/reset/Kconfig | 5 ++ drivers/power/reset/Makefile | 1 + drivers/power/reset/syscon-reboot.c | 96 +++++++++++++++++++++++++++++++++++++ 3 files changed, 102 insertions(+) create mode 100644 drivers/power/reset/syscon-reboot.c