From patchwork Thu Aug 9 13:53:45 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eugen Hristev X-Patchwork-Id: 143862 Delivered-To: patch@linaro.org Received: by 2002:a2e:9754:0:0:0:0:0 with SMTP id f20-v6csp2130354ljj; Thu, 9 Aug 2018 07:00:33 -0700 (PDT) X-Google-Smtp-Source: AA+uWPw46fHfGkXyM0qZlSCDPoGTqWVh4SkODgWHBEQp6AjVzU8fjfa29CKBdU/IciB+fAHDTAW+ X-Received: by 2002:aa7:c4cf:: with SMTP id p15-v6mr3476643edr.240.1533823233539; Thu, 09 Aug 2018 07:00:33 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1533823233; cv=none; d=google.com; s=arc-20160816; b=kWABRvFmU4qZ8tC0YTisyuWZqIDCr/15kP68WO5+eJ1+4lwnR1iUYAamHd/W4oAy5f r8+lNA90ZX8E0h6S1Tkv3A9kq3XsQAmIUIl8I4xyaQzByf4P1Jwzx1wwYvUc1cWN0zbT P31WaZIYdZ0TkG7an+7K/vA804yzHl1SwgDFW2t+u4ybTBMYeWesxPZJqEmtEeO8f1uE UYT8mJH472UkmQRshnuqpuTmpPaiXKinTAYecvPE0KTPizTf/x5kNJcnpBIUx35N1DuJ Acek3Luf2x80vD0zJ4vN98OoDhIzCPsBW3URiUGRHmnnQeKdeFfaiVidOMjRzVacTG9r 01QQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=sender:errors-to:content-transfer-encoding:list-subscribe:list-help :list-post:list-archive:list-unsubscribe:list-id:precedence:subject :cc:mime-version:references:in-reply-to:message-id:date:to:from :arc-authentication-results; bh=217G6gDyE1JFFnKeVGPgMn+t+/8hNBJr3OfJAl19KQM=; b=H0qAnbdwNa+n4/lDDO/gDhXxtX/bBICTmjSRyz3E2gwdYBykuFW5Cws4IWfrfB400h Zlz2UCVG8298P+0Z+aY+1+HC1KSMFWRB6fQYDJBqCONs4B1aFLodeVycYLRuZ/2eHVf9 r2HltA6jSHQk2iOdiS0/aHiQIt1O1TeLUvo1Mh21x9qYhNCG0JNCymL+hAxu0WGk9dCJ DhJ1+aa3QI+JwhaVy6rqUNFABPtrQbOxc6w8OFqQUwzNc/lQJR8iS5yJrpxWvRxolp1r zKTBl5EyXD9DIAfYizMiBMgsC3l5ISg7OqEeAOoMNvH2bSq4TaOMl8rRU/FER0+UjSO9 sLww== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of u-boot-bounces@lists.denx.de designates 81.169.180.215 as permitted sender) smtp.mailfrom=u-boot-bounces@lists.denx.de Return-Path: Received: from lists.denx.de (dione.denx.de. [81.169.180.215]) by mx.google.com with ESMTP id e29-v6si841604eda.181.2018.08.09.07.00.33; Thu, 09 Aug 2018 07:00:33 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of u-boot-bounces@lists.denx.de designates 81.169.180.215 as permitted sender) client-ip=81.169.180.215; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of u-boot-bounces@lists.denx.de designates 81.169.180.215 as permitted sender) smtp.mailfrom=u-boot-bounces@lists.denx.de Received: by lists.denx.de (Postfix, from userid 105) id 239F7C21F32; Thu, 9 Aug 2018 14:00:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on lists.denx.de X-Spam-Level: X-Spam-Status: No, score=0.0 required=5.0 tests=none autolearn=unavailable autolearn_force=no version=3.4.0 Received: from lists.denx.de (localhost [IPv6:::1]) by lists.denx.de (Postfix) with ESMTP id 90135C21D56; Thu, 9 Aug 2018 13:59:23 +0000 (UTC) Received: by lists.denx.de (Postfix, from userid 105) id 8A5C5C21C4A; Thu, 9 Aug 2018 13:59:21 +0000 (UTC) Received: from esa6.microchip.iphmx.com (esa6.microchip.iphmx.com [216.71.154.253]) by lists.denx.de (Postfix) with ESMTPS id 94ABFC21C27 for ; Thu, 9 Aug 2018 13:59:20 +0000 (UTC) X-IronPort-AV: E=Sophos;i="5.53,215,1531810800"; d="scan'208";a="14954981" Received: from smtpout.microchip.com (HELO email.microchip.com) ([198.175.253.82]) by esa6.microchip.iphmx.com with ESMTP/TLS/DHE-RSA-AES256-SHA; 09 Aug 2018 06:59:18 -0700 Received: from eh-station.mchp-main.com (10.10.76.4) by chn-sv-exch07.mchp-main.com (10.10.76.108) with Microsoft SMTP Server id 14.3.352.0; Thu, 9 Aug 2018 06:59:17 -0700 From: Eugen Hristev To: Date: Thu, 9 Aug 2018 16:53:45 +0300 Message-ID: <1533822854-4349-2-git-send-email-eugen.hristev@microchip.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1533822854-4349-1-git-send-email-eugen.hristev@microchip.com> References: <1533822854-4349-1-git-send-email-eugen.hristev@microchip.com> MIME-Version: 1.0 Cc: Maxime Ripard , nicolas.ferre@microchip.com Subject: [U-Boot] [PATCH v2 01/30] w1: Add 1-Wire uclass X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.18 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" From: Maxime Ripard We might want to use 1-Wire devices connected on boards such as EEPROMs in U-Boot. Provide a framework to be able to do that. Signed-off-by: Maxime Ripard [eugen.hristev@microchip.com: reworked] Signed-off-by: Eugen Hristev --- drivers/Kconfig | 2 + drivers/Makefile | 1 + drivers/w1/Kconfig | 18 ++++ drivers/w1/Makefile | 1 + drivers/w1/w1-uclass.c | 235 +++++++++++++++++++++++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/w1.h | 36 ++++++++ 7 files changed, 294 insertions(+) create mode 040000 drivers/w1 create mode 100644 drivers/w1/Kconfig create mode 100644 drivers/w1/Makefile create mode 100644 drivers/w1/w1-uclass.c create mode 100644 include/w1.h diff --git a/drivers/Kconfig b/drivers/Kconfig index 9e21b28..2cae829 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -102,6 +102,8 @@ source "drivers/usb/Kconfig" source "drivers/video/Kconfig" +source "drivers/w1/Kconfig" + source "drivers/watchdog/Kconfig" config PHYS_TO_BUS diff --git a/drivers/Makefile b/drivers/Makefile index a213ea9..728380b 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -101,6 +101,7 @@ obj-y += input/ obj-y += soc/ obj-$(CONFIG_REMOTEPROC) += remoteproc/ obj-y += thermal/ +obj-$(CONFIG_W1) += w1/ obj-$(CONFIG_MACH_PIC32) += ddr/microchip/ endif diff --git a/drivers/w1/Kconfig b/drivers/w1/Kconfig new file mode 100644 index 0000000..64b27c6 --- /dev/null +++ b/drivers/w1/Kconfig @@ -0,0 +1,18 @@ +# +# W1 subsystem configuration +# + +menu "1-Wire support" + +config W1 + bool "Enable 1-wire controllers support" + default no + depends on DM + help + Support for the Dallas 1-Wire bus. + +if W1 + +endif + +endmenu diff --git a/drivers/w1/Makefile b/drivers/w1/Makefile new file mode 100644 index 0000000..f81693b --- /dev/null +++ b/drivers/w1/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_W1) += w1-uclass.o diff --git a/drivers/w1/w1-uclass.c b/drivers/w1/w1-uclass.c new file mode 100644 index 0000000..9c9cd90 --- /dev/null +++ b/drivers/w1/w1-uclass.c @@ -0,0 +1,235 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * + * Copyright (c) 2015 Free Electrons + * Copyright (c) 2015 NextThing Co. + * Copyright (c) 2018 Microchip Technology, Inc. + * + * Maxime Ripard + * Eugen Hristev + * + */ + +#include +#include +#include + +#include + +#define W1_MATCH_ROM 0x55 +#define W1_SKIP_ROM 0xcc +#define W1_SEARCH 0xf0 + +struct w1_bus { + u64 search_id; +}; + +static int w1_enumerate(struct udevice *bus) +{ + const struct w1_ops *ops = device_get_ops(bus); + struct w1_bus *w1 = dev_get_uclass_priv(bus); + u64 last_rn, rn = w1->search_id, tmp64; + bool last_device = false; + int search_bit, desc_bit = 64; + int last_zero = -1; + u8 triplet_ret = 0; + int i; + + if (!ops->reset || !ops->write_byte || !ops->triplet) + return -ENOSYS; + + while (!last_device) { + last_rn = rn; + rn = 0; + + /* + * Reset bus and all 1-wire device state machines + * so they can respond to our requests. + * + * Return 0 - device(s) present, 1 - no devices present. + */ + if (ops->reset(bus)) { + debug("%s: No devices present on the wire.\n", + __func__); + break; + } + + /* Start the search */ + ops->write_byte(bus, W1_SEARCH); + for (i = 0; i < 64; ++i) { + /* Determine the direction/search bit */ + if (i == desc_bit) + /* took the 0 path last time, so take the 1 path */ + search_bit = 1; + else if (i > desc_bit) + /* take the 0 path on the next branch */ + search_bit = 0; + else + search_bit = ((last_rn >> i) & 0x1); + + /* Read two bits and write one bit */ + triplet_ret = ops->triplet(bus, search_bit); + + /* quit if no device responded */ + if ((triplet_ret & 0x03) == 0x03) + break; + + /* If both directions were valid, and we took the 0 path... */ + if (triplet_ret == 0) + last_zero = i; + + /* extract the direction taken & update the device number */ + tmp64 = (triplet_ret >> 2); + rn |= (tmp64 << i); + } + + /* last device or error, aborting here */ + if ((triplet_ret & 0x03) == 0x03) + last_device = true; + + if ((triplet_ret & 0x03) != 0x03) { + if (desc_bit == last_zero || last_zero < 0) { + last_device = 1; + w1->search_id = 0; + } else { + w1->search_id = rn; + } + desc_bit = last_zero; + + debug("%s: Detected new device 0x%llx (family 0x%x)\n", + bus->name, rn, (u8)(rn & 0xff)); + } + } + + return 0; +} + +int w1_get_bus(int busnum, struct udevice **busp) +{ + int ret, i = 0; + + struct udevice *dev; + + for (ret = uclass_first_device(UCLASS_W1, &dev); + !ret; + uclass_next_device(&dev), i++) { + if (ret) { + debug("Cannot find w1 bus %d\n", busnum); + return ret; + } + if (i == busnum) { + *busp = dev; + return 0; + } + } + return ret; +} + +u8 w1_get_device_family(struct udevice *dev) +{ + struct w1_device *w1 = dev_get_parent_platdata(dev); + + return w1->id & 0xff; +} + +int w1_reset_select(struct udevice *dev) +{ + struct w1_device *w1 = dev_get_platdata(dev); + struct udevice *bus = dev_get_parent(dev); + const struct w1_ops *ops = device_get_ops(bus); + int i; + + if (!ops->reset || !ops->write_byte) + return -ENOSYS; + + ops->reset(bus); + + ops->write_byte(bus, W1_MATCH_ROM); + + for (i = 0; i < sizeof(w1->id); i++) + ops->write_byte(bus, (w1->id >> (i * 8)) & 0xff); + + return 0; +} + +int w1_read_byte(struct udevice *dev) +{ + struct udevice *bus = dev_get_parent(dev); + const struct w1_ops *ops = device_get_ops(bus); + + if (!ops->read_byte) + return -ENOSYS; + + return ops->read_byte(bus); +} + +int w1_read_buf(struct udevice *dev, u8 *buf, unsigned int count) +{ + int i, ret; + + for (i = 0; i < count; i++) { + ret = w1_read_byte(dev); + if (ret < 0) + return ret; + + buf[i] = ret & 0xff; + } + + return 0; +} + +int w1_write_byte(struct udevice *dev, u8 byte) +{ + struct udevice *bus = dev_get_parent(dev); + const struct w1_ops *ops = device_get_ops(bus); + + if (!ops->write_byte) + return -ENOSYS; + + ops->write_byte(bus, byte); + + return 0; +} + +static int w1_post_probe(struct udevice *bus) +{ + w1_enumerate(bus); + + return 0; +} + +int w1_init(void) +{ + struct udevice *bus; + struct uclass *uc; + int ret; + + ret = uclass_get(UCLASS_W1, &uc); + if (ret) + return ret; + + uclass_foreach_dev(bus, uc) { + ret = device_probe(bus); + if (ret == -ENODEV) { /* No such device. */ + printf("W1 controller not available.\n"); + continue; + } + + if (ret) { /* Other error. */ + printf("W1 controller probe failed.\n"); + continue; + } + } + return 0; +} + +UCLASS_DRIVER(w1) = { + .name = "w1", + .id = UCLASS_W1, + .flags = DM_UC_FLAG_SEQ_ALIAS, + .per_device_auto_alloc_size = sizeof(struct w1_bus), + .post_probe = w1_post_probe, +#if CONFIG_IS_ENABLED(OF_CONTROL) + .post_bind = dm_scan_fdt_dev, +#endif +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index d7f9df3..8eca9dc 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -89,6 +89,7 @@ enum uclass_id { UCLASS_VIDEO, /* Video or LCD device */ UCLASS_VIDEO_BRIDGE, /* Video bridge, e.g. DisplayPort to LVDS */ UCLASS_VIDEO_CONSOLE, /* Text console driver for video device */ + UCLASS_W1, /* Dallas 1-Wire bus */ UCLASS_WDT, /* Watchdot Timer driver */ UCLASS_COUNT, diff --git a/include/w1.h b/include/w1.h new file mode 100644 index 0000000..b36e0f8 --- /dev/null +++ b/include/w1.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0+ + * + * Copyright (c) 2015 Free Electrons + * Copyright (c) 2015 NextThing Co + * + */ + +#ifndef __W1_H +#define __W1_H + +#include + +#define W1_FAMILY_DS24B33 0x23 +#define W1_FAMILY_DS2431 0x2d + +struct w1_device { + u64 id; +}; + +struct w1_ops { + u8 (*read_byte)(struct udevice *dev); + bool (*reset)(struct udevice *dev); + u8 (*triplet)(struct udevice *dev, bool bdir); + void (*write_byte)(struct udevice *dev, u8 byte); +}; + +int w1_get_bus(int busnum, struct udevice **busp); +u8 w1_get_device_family(struct udevice *dev); + +int w1_read_buf(struct udevice *dev, u8 *buf, unsigned int count); +int w1_read_byte(struct udevice *dev); +int w1_reset_select(struct udevice *dev); +int w1_write_buf(struct udevice *dev, u8 *buf, unsigned int count); +int w1_write_byte(struct udevice *dev, u8 byte); + +#endif