From patchwork Fri Aug 9 10:32:23 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Bogendoerfer X-Patchwork-Id: 11086177 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 091B0112C for ; Fri, 9 Aug 2019 10:32:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ED61E28C66 for ; Fri, 9 Aug 2019 10:32:47 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E123C28C76; Fri, 9 Aug 2019 10:32:47 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable 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 2501428C7F for ; Fri, 9 Aug 2019 10:32:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2406115AbfHIKcp (ORCPT ); Fri, 9 Aug 2019 06:32:45 -0400 Received: from mx2.suse.de ([195.135.220.15]:41570 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2405723AbfHIKcp (ORCPT ); Fri, 9 Aug 2019 06:32:45 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id DA51BAFF0; Fri, 9 Aug 2019 10:32:42 +0000 (UTC) From: Thomas Bogendoerfer To: Ralf Baechle , Paul Burton , James Hogan , Dmitry Torokhov , Lee Jones , "David S. Miller" , Srinivas Kandagatla , Alessandro Zummo , Alexandre Belloni , Greg Kroah-Hartman , Jiri Slaby , Evgeniy Polyakov , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, netdev@vger.kernel.org, linux-rtc@vger.kernel.org, linux-serial@vger.kernel.org Subject: [PATCH v4 1/9] w1: add 1-wire master driver for IP block found in SGI ASICs Date: Fri, 9 Aug 2019 12:32:23 +0200 Message-Id: <20190809103235.16338-2-tbogendoerfer@suse.de> X-Mailer: git-send-email 2.13.7 In-Reply-To: <20190809103235.16338-1-tbogendoerfer@suse.de> References: <20190809103235.16338-1-tbogendoerfer@suse.de> Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Starting with SGI Origin machines nearly every new SGI ASIC contains an 1-Wire master. They are used for attaching One-Wire prom devices, which contain information about part numbers, revision numbers, serial number etc. and MAC addresses for ethernet interfaces. This patch adds a master driver to support this IP block. It also adds an extra field dev_id to struct w1_bus_master, which could be in used in slave drivers for creating unique device names. Signed-off-by: Thomas Bogendoerfer --- drivers/w1/masters/Kconfig | 9 +++ drivers/w1/masters/Makefile | 1 + drivers/w1/masters/sgi_w1.c | 130 +++++++++++++++++++++++++++++++++++ include/linux/platform_data/sgi-w1.h | 15 ++++ include/linux/w1.h | 2 + 5 files changed, 157 insertions(+) create mode 100644 drivers/w1/masters/sgi_w1.c create mode 100644 include/linux/platform_data/sgi-w1.h diff --git a/drivers/w1/masters/Kconfig b/drivers/w1/masters/Kconfig index 7ae260577901..24b9a8e05f64 100644 --- a/drivers/w1/masters/Kconfig +++ b/drivers/w1/masters/Kconfig @@ -65,5 +65,14 @@ config HDQ_MASTER_OMAP Say Y here if you want support for the 1-wire or HDQ Interface on an OMAP processor. +config W1_MASTER_SGI + tristate "SGI ASIC driver" + help + Say Y here if you want support for your 1-wire devices using + SGI ASIC 1-Wire interface + + This support is also available as a module. If so, the module + will be called sgi_w1. + endmenu diff --git a/drivers/w1/masters/Makefile b/drivers/w1/masters/Makefile index 18954cae4256..dae629b7ab49 100644 --- a/drivers/w1/masters/Makefile +++ b/drivers/w1/masters/Makefile @@ -11,3 +11,4 @@ obj-$(CONFIG_W1_MASTER_MXC) += mxc_w1.o obj-$(CONFIG_W1_MASTER_DS1WM) += ds1wm.o obj-$(CONFIG_W1_MASTER_GPIO) += w1-gpio.o obj-$(CONFIG_HDQ_MASTER_OMAP) += omap_hdq.o +obj-$(CONFIG_W1_MASTER_SGI) += sgi_w1.o diff --git a/drivers/w1/masters/sgi_w1.c b/drivers/w1/masters/sgi_w1.c new file mode 100644 index 000000000000..1b2d96b945be --- /dev/null +++ b/drivers/w1/masters/sgi_w1.c @@ -0,0 +1,130 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * sgi_w1.c - w1 master driver for one wire support in SGI ASICs + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define MCR_RD_DATA BIT(0) +#define MCR_DONE BIT(1) + +#define MCR_PACK(pulse, sample) (((pulse) << 10) | ((sample) << 2)) + +struct sgi_w1_device { + u32 __iomem *mcr; + struct w1_bus_master bus_master; + char dev_id[64]; +}; + +static u8 sgi_w1_wait(u32 __iomem *mcr) +{ + u32 mcr_val; + + do { + mcr_val = readl(mcr); + } while (!(mcr_val & MCR_DONE)); + + return (mcr_val & MCR_RD_DATA) ? 1 : 0; +} + +/* + * this is the low level routine to + * reset the device on the One Wire interface + * on the hardware + */ +static u8 sgi_w1_reset_bus(void *data) +{ + struct sgi_w1_device *dev = data; + u8 ret; + + writel(MCR_PACK(520, 65), dev->mcr); + ret = sgi_w1_wait(dev->mcr); + udelay(500); /* recovery time */ + return ret; +} + +/* + * this is the low level routine to read/write a bit on the One Wire + * interface on the hardware. It does write 0 if parameter bit is set + * to 0, otherwise a write 1/read. + */ +static u8 sgi_w1_touch_bit(void *data, u8 bit) +{ + struct sgi_w1_device *dev = data; + u8 ret; + + if (bit) + writel(MCR_PACK(6, 13), dev->mcr); + else + writel(MCR_PACK(80, 30), dev->mcr); + + ret = sgi_w1_wait(dev->mcr); + if (bit) + udelay(100); /* recovery */ + return ret; +} + +static int sgi_w1_probe(struct platform_device *pdev) +{ + struct sgi_w1_device *sdev; + struct sgi_w1_platform_data *pdata; + struct resource *res; + + sdev = devm_kzalloc(&pdev->dev, sizeof(struct sgi_w1_device), + GFP_KERNEL); + if (!sdev) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + sdev->mcr = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(sdev->mcr)) + return PTR_ERR(sdev->mcr); + + sdev->bus_master.data = sdev; + sdev->bus_master.reset_bus = sgi_w1_reset_bus; + sdev->bus_master.touch_bit = sgi_w1_touch_bit; + + pdata = dev_get_platdata(&pdev->dev); + if (pdata) { + strlcpy(sdev->dev_id, pdata->dev_id, sizeof(sdev->dev_id)); + sdev->bus_master.dev_id = sdev->dev_id; + } + + platform_set_drvdata(pdev, sdev); + + return w1_add_master_device(&sdev->bus_master); +} + +/* + * disassociate the w1 device from the driver + */ +static int sgi_w1_remove(struct platform_device *pdev) +{ + struct sgi_w1_device *sdev = platform_get_drvdata(pdev); + + w1_remove_master_device(&sdev->bus_master); + + return 0; +} + +static struct platform_driver sgi_w1_driver = { + .driver = { + .name = "sgi_w1", + }, + .probe = sgi_w1_probe, + .remove = sgi_w1_remove, +}; +module_platform_driver(sgi_w1_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Thomas Bogendoerfer"); +MODULE_DESCRIPTION("Driver for One-Wire IP in SGI ASICs"); diff --git a/include/linux/platform_data/sgi-w1.h b/include/linux/platform_data/sgi-w1.h new file mode 100644 index 000000000000..fc6b92e0b942 --- /dev/null +++ b/include/linux/platform_data/sgi-w1.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * SGI One-Wire (W1) IP + */ + +#ifndef PLATFORM_DATA_SGI_W1_H +#define PLATFORM_DATA_SGI_W1_H + +#include + +struct sgi_w1_platform_data { + char dev_id[64]; +}; + +#endif /* PLATFORM_DATA_SGI_W1_H */ diff --git a/include/linux/w1.h b/include/linux/w1.h index e0b5156f78fd..89843e9f634c 100644 --- a/include/linux/w1.h +++ b/include/linux/w1.h @@ -150,6 +150,8 @@ struct w1_bus_master { void (*search)(void *, struct w1_master *, u8, w1_slave_found_callback); + + char *dev_id; }; /**