From patchwork Fri May 26 12:12:42 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 9750503 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1066B60390 for ; Fri, 26 May 2017 12:13:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0A19A2624B for ; Fri, 26 May 2017 12:13:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id F2ECB28347; Fri, 26 May 2017 12:13:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6159F2833E for ; Fri, 26 May 2017 12:13:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1164103AbdEZMNG (ORCPT ); Fri, 26 May 2017 08:13:06 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:37574 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752872AbdEZMNC (ORCPT ); Fri, 26 May 2017 08:13:02 -0400 Received: from [2001:470:1f1d:6b5::3] (helo=debutante) by mezzanine.sirena.org.uk with esmtpsa (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.84_2) (envelope-from ) id 1dEE6m-0000gr-VX; Fri, 26 May 2017 12:12:47 +0000 Received: from broonie by debutante with local (Exim 4.89) (envelope-from ) id 1dEE6k-0001Nd-0c; Fri, 26 May 2017 13:12:42 +0100 From: Mark Brown To: Geert Uytterhoeven Cc: Mark Brown , Mark Brown , Rob Herring , Mark Rutland , Magnus Damm , Wolfram Sang , Hiromitsu Yamasaki , Jiada Wang , Matt Porter , linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org In-Reply-To: <1495458705-11692-7-git-send-email-geert+renesas@glider.be> Message-Id: Date: Fri, 26 May 2017 13:12:42 +0100 X-SA-Exim-Connect-IP: 2001:470:1f1d:6b5::3 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Applied "spi: slave: Add SPI slave handler controlling system state" to the spi tree X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: No (on mezzanine.sirena.org.uk); Unknown failure Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The patch spi: slave: Add SPI slave handler controlling system state has been applied to the spi tree at git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted. You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed. If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced. Please add any relevant lists and maintainers to the CCs when replying to this mail. Thanks, Mark From ce70e06c093a9609377e93ee20e7c528e156af14 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Mon, 22 May 2017 15:11:45 +0200 Subject: [PATCH] spi: slave: Add SPI slave handler controlling system state Add an example SPI slave handler to allow remote control of system reboot, power off, halt, and suspend. Signed-off-by: Geert Uytterhoeven Reviewed-by: Andy Shevchenko Signed-off-by: Mark Brown --- drivers/spi/Kconfig | 6 ++ drivers/spi/Makefile | 1 + drivers/spi/spi-slave-system-control.c | 154 +++++++++++++++++++++++++++++++++ 3 files changed, 161 insertions(+) create mode 100644 drivers/spi/spi-slave-system-control.c diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index ade542c5bfd8..e6d9e329a380 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -802,6 +802,12 @@ config SPI_SLAVE_TIME SPI slave handler responding with the time of reception of the last SPI message. +config SPI_SLAVE_SYSTEM_CONTROL + tristate "SPI slave handler controlling system state" + help + SPI slave handler to allow remote control of system reboot, power + off, halt, and suspend. + endif # SPI_SLAVE endif # SPI diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index fb078693dbe4..1d7923e8c63b 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -108,3 +108,4 @@ obj-$(CONFIG_SPI_ZYNQMP_GQSPI) += spi-zynqmp-gqspi.o # SPI slave protocol handlers obj-$(CONFIG_SPI_SLAVE_TIME) += spi-slave-time.o +obj-$(CONFIG_SPI_SLAVE_SYSTEM_CONTROL) += spi-slave-system-control.o diff --git a/drivers/spi/spi-slave-system-control.c b/drivers/spi/spi-slave-system-control.c new file mode 100644 index 000000000000..c0257e937995 --- /dev/null +++ b/drivers/spi/spi-slave-system-control.c @@ -0,0 +1,154 @@ +/* + * SPI slave handler controlling system state + * + * This SPI slave handler allows remote control of system reboot, power off, + * halt, and suspend. + * + * Copyright (C) 2016-2017 Glider bvba + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Usage (assuming /dev/spidev2.0 corresponds to the SPI master on the remote + * system): + * + * # reboot='\x7c\x50' + * # poweroff='\x71\x3f' + * # halt='\x38\x76' + * # suspend='\x1b\x1b' + * # spidev_test -D /dev/spidev2.0 -p $suspend # or $reboot, $poweroff, $halt + */ + +#include +#include +#include +#include +#include + +/* + * The numbers are chosen to display something human-readable on two 7-segment + * displays connected to two 74HC595 shift registers + */ +#define CMD_REBOOT 0x7c50 /* rb */ +#define CMD_POWEROFF 0x713f /* OF */ +#define CMD_HALT 0x3876 /* HL */ +#define CMD_SUSPEND 0x1b1b /* ZZ */ + +struct spi_slave_system_control_priv { + struct spi_device *spi; + struct completion finished; + struct spi_transfer xfer; + struct spi_message msg; + __be16 cmd; +}; + +static +int spi_slave_system_control_submit(struct spi_slave_system_control_priv *priv); + +static void spi_slave_system_control_complete(void *arg) +{ + struct spi_slave_system_control_priv *priv = arg; + u16 cmd; + int ret; + + if (priv->msg.status) + goto terminate; + + cmd = be16_to_cpu(priv->cmd); + switch (cmd) { + case CMD_REBOOT: + dev_info(&priv->spi->dev, "Rebooting system...\n"); + kernel_restart(NULL); + + case CMD_POWEROFF: + dev_info(&priv->spi->dev, "Powering off system...\n"); + kernel_power_off(); + break; + + case CMD_HALT: + dev_info(&priv->spi->dev, "Halting system...\n"); + kernel_halt(); + break; + + case CMD_SUSPEND: + dev_info(&priv->spi->dev, "Suspending system...\n"); + pm_suspend(PM_SUSPEND_MEM); + break; + + default: + dev_warn(&priv->spi->dev, "Unknown command 0x%x\n", cmd); + break; + } + + ret = spi_slave_system_control_submit(priv); + if (ret) + goto terminate; + + return; + +terminate: + dev_info(&priv->spi->dev, "Terminating\n"); + complete(&priv->finished); +} + +static +int spi_slave_system_control_submit(struct spi_slave_system_control_priv *priv) +{ + int ret; + + spi_message_init_with_transfers(&priv->msg, &priv->xfer, 1); + + priv->msg.complete = spi_slave_system_control_complete; + priv->msg.context = priv; + + ret = spi_async(priv->spi, &priv->msg); + if (ret) + dev_err(&priv->spi->dev, "spi_async() failed %d\n", ret); + + return ret; +} + +static int spi_slave_system_control_probe(struct spi_device *spi) +{ + struct spi_slave_system_control_priv *priv; + int ret; + + priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->spi = spi; + init_completion(&priv->finished); + priv->xfer.rx_buf = &priv->cmd; + priv->xfer.len = sizeof(priv->cmd); + + ret = spi_slave_system_control_submit(priv); + if (ret) + return ret; + + spi_set_drvdata(spi, priv); + return 0; +} + +static int spi_slave_system_control_remove(struct spi_device *spi) +{ + struct spi_slave_system_control_priv *priv = spi_get_drvdata(spi); + + spi_slave_abort(spi); + wait_for_completion(&priv->finished); + return 0; +} + +static struct spi_driver spi_slave_system_control_driver = { + .driver = { + .name = "spi-slave-system-control", + }, + .probe = spi_slave_system_control_probe, + .remove = spi_slave_system_control_remove, +}; +module_spi_driver(spi_slave_system_control_driver); + +MODULE_AUTHOR("Geert Uytterhoeven "); +MODULE_DESCRIPTION("SPI slave handler controlling system state"); +MODULE_LICENSE("GPL v2");