From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751873AbaJADMW (ORCPT ); Tue, 30 Sep 2014 23:12:22 -0400 Received: from bh-25.webhostbox.net ([208.91.199.152]:49131 "EHLO bh-25.webhostbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751042AbaJADMU (ORCPT ); Tue, 30 Sep 2014 23:12:20 -0400 Message-ID: <542B70D4.8040001@roeck-us.net> Date: Tue, 30 Sep 2014 20:11:16 -0700 From: Guenter Roeck User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Feng Kan , dbaryshkov@gmail.com, catalin.marinas@arm.com, dwmw2@infradead.org, arnd@arndb.de, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, patches@apm.com, linux-pm@vger.kernel.org, will.deacon@arm.com Subject: Re: [PATCH RESEND V9 1/6] power: reset: Add generic SYSCON register mapped reset References: <1412119508-22864-1-git-send-email-fkan@apm.com> <1412119508-22864-2-git-send-email-fkan@apm.com> In-Reply-To: <1412119508-22864-2-git-send-email-fkan@apm.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Authenticated_sender: linux@roeck-us.net X-OutGoing-Spam-Status: No, score=-1.0 X-CTCH-PVer: 0000001 X-CTCH-Spam: Unknown X-CTCH-VOD: Unknown X-CTCH-Flags: 0 X-CTCH-RefID: str=0001.0A02020A.542B7114.0077,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0 X-CTCH-Score: 0.000 X-CTCH-ScoreCust: 0.000 X-CTCH-Rules: X-CTCH-SenderID: linux@roeck-us.net X-CTCH-SenderID-Flags: 0 X-CTCH-SenderID-TotalMessages: 4 X-CTCH-SenderID-TotalSpam: 0 X-CTCH-SenderID-TotalSuspected: 0 X-CTCH-SenderID-TotalConfirmed: 0 X-CTCH-SenderID-TotalBulk: 0 X-CTCH-SenderID-TotalVirus: 0 X-CTCH-SenderID-TotalRecipients: 0 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - bh-25.webhostbox.net X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - roeck-us.net X-Get-Message-Sender-Via: bh-25.webhostbox.net: mailgid no entry from get_relayhosts_entry X-Source: X-Source-Args: X-Source-Dir: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/30/2014 04:25 PM, Feng Kan wrote: > Add a generic SYSCON register mapped reset mechanism. > > Signed-off-by: Feng Kan > --- > 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 > + * > + * 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 > +#include > +#include > +#include > +#include alphabetic order of include files ? > +#include > +#include > +#include > + > +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); >