On Thu, Jun 26, 2014 at 7:03 AM, Feng Kan <fkan@xxxxxxx> wrote: > Add a generic SYSCON register mapped reset mechanism. > > Signed-off-by: Feng Kan <fkan@xxxxxxx> > --- > drivers/power/reset/Kconfig | 6 +++ > drivers/power/reset/Makefile | 1 + > drivers/power/reset/syscon-reboot.c | 91 +++++++++++++++++++++++++++++++++++++ > 3 files changed, 98 insertions(+) > create mode 100644 drivers/power/reset/syscon-reboot.c > > diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig > index bdcf517..7035236 100644 > --- a/drivers/power/reset/Kconfig > +++ b/drivers/power/reset/Kconfig > @@ -80,3 +80,9 @@ config POWER_RESET_KEYSTONE > help > Reboot support for the KEYSTONE SoCs. > > +config POWER_RESET_SYSCON > + bool "Generic SYSCON regmap reset driver" > + depends on ARCH_XGENE If this is supposed to be generic, why are you depending on a certain platform? ChenYu > + depends on POWER_RESET && MFD_SYSCON > + help > + Reboot support for generic SYSCON mapped register reset. > diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile > index dde2e8b..b1b5ab3 100644 > --- a/drivers/power/reset/Makefile > +++ b/drivers/power/reset/Makefile > @@ -8,3 +8,4 @@ obj-$(CONFIG_POWER_RESET_SUN6I) += sun6i-reboot.o > obj-$(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..9c15ba5 > --- /dev/null > +++ b/drivers/power/reset/syscon-reboot.c > @@ -0,0 +1,91 @@ > +/* > + * Generic Syscon Reboot Driver > + * > + * Copyright (c) 2013, Applied Micro Circuits Corporation > + * Author: Feng Kan <fkan@xxxxxxx> > + * > + * 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/stat.h> > +#include <linux/slab.h> > +#include <linux/mfd/syscon.h> > +#include <linux/regmap.h> > +#include <linux/reboot.h> > +#include <asm/system_misc.h> > + > +struct syscon_reboot_context { > + struct regmap *map; > + u32 offset; > + u32 mask; > +}; > + > +static struct syscon_reboot_context *syscon_reboot_ctx; > + > +static void syscon_restart(enum reboot_mode reboot_mode, const char *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"); > +} > + > +static int syscon_reboot_probe(struct platform_device *pdev) > +{ > + struct syscon_reboot_context *ctx; > + struct device *dev = &pdev->dev; > + > + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); > + if (!ctx) { > + dev_err(&pdev->dev, "out of memory for context\n"); > + 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; > + > + arm_pm_restart = syscon_restart; > + 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); > -- > 1.9.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html