From patchwork Mon May 10 05:10:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aswath Govindraju X-Patchwork-Id: 433313 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-21.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 66922C43460 for ; Mon, 10 May 2021 05:11:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A6FA61430 for ; Mon, 10 May 2021 05:11:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230103AbhEJFMN (ORCPT ); Mon, 10 May 2021 01:12:13 -0400 Received: from fllv0015.ext.ti.com ([198.47.19.141]:50662 "EHLO fllv0015.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230009AbhEJFMM (ORCPT ); Mon, 10 May 2021 01:12:12 -0400 Received: from lelv0266.itg.ti.com ([10.180.67.225]) by fllv0015.ext.ti.com (8.15.2/8.15.2) with ESMTP id 14A5Awlf073683; Mon, 10 May 2021 00:10:58 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1620623458; bh=Uh1qoqnku6rqZX6bcJktkny0EFpSCkE0+xsfey1mpvk=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=OHVlZiV1Pp8wCrCViSLYK/tDIENtu9zyKJz9tizB0Eyct/f9IAolSX8k8cf0TfeNo B9aq4G7sE8QDaABAf52DlmobBDfKEbdz/bnwFquajRJsJWvSOHyZtT5v9DPEO8tCwN K4oEUINsRu8D1cVi30wo61Wk/GhDvX4nzT7VWX4Q= Received: from DFLE113.ent.ti.com (dfle113.ent.ti.com [10.64.6.34]) by lelv0266.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 14A5AwHT114666 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 10 May 2021 00:10:58 -0500 Received: from DFLE111.ent.ti.com (10.64.6.32) by DFLE113.ent.ti.com (10.64.6.34) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Mon, 10 May 2021 00:10:58 -0500 Received: from lelv0327.itg.ti.com (10.180.67.183) by DFLE111.ent.ti.com (10.64.6.32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2 via Frontend Transport; Mon, 10 May 2021 00:10:58 -0500 Received: from gsaswath-HP-ProBook-640-G5.dal.design.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by lelv0327.itg.ti.com (8.15.2/8.15.2) with ESMTP id 14A5A9nO113970; Mon, 10 May 2021 00:10:50 -0500 From: Aswath Govindraju CC: , Marc Kleine-Budde , Wolfgang Grandegger , Vignesh Raghavendra , Lokesh Vutla , Aswath Govindraju , Kishon Vijay Abraham I , Vinod Koul , Rob Herring , , , Subject: [PATCH v6 3/3] phy: phy-can-transceiver: Add support for generic CAN transceiver driver Date: Mon, 10 May 2021 10:40:05 +0530 Message-ID: <20210510051006.11393-4-a-govindraju@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210510051006.11393-1-a-govindraju@ti.com> References: <20210510051006.11393-1-a-govindraju@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 To: unlisted-recipients:; (no To-header on input) Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The driver adds support for generic CAN transceivers. Currently the modes supported by this driver are standby and normal modes for TI TCAN1042 and TCAN1043 CAN transceivers. The transceiver is modelled as a phy with pins controlled by gpios, to put the transceiver in various device functional modes. It also gets the phy attribute max_link_rate for the usage of CAN drivers. Signed-off-by: Aswath Govindraju Acked-by: Marc Kleine-Budde --- MAINTAINERS | 1 + drivers/phy/Kconfig | 9 ++ drivers/phy/Makefile | 1 + drivers/phy/phy-can-transceiver.c | 146 ++++++++++++++++++++++++++++++ 4 files changed, 157 insertions(+) create mode 100644 drivers/phy/phy-can-transceiver.c diff --git a/MAINTAINERS b/MAINTAINERS index 492eb53c0db0..e7bd53caf5ff 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4042,6 +4042,7 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next.git F: Documentation/devicetree/bindings/net/can/ F: Documentation/devicetree/bindings/phy/ti,tcan104x-can.yaml F: drivers/net/can/ +F: drivers/phy/phy-can-transceiver.c F: include/linux/can/bittiming.h F: include/linux/can/dev.h F: include/linux/can/led.h diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig index 54c1f2f0985f..7dd35f1b9cc5 100644 --- a/drivers/phy/Kconfig +++ b/drivers/phy/Kconfig @@ -61,6 +61,15 @@ config USB_LGM_PHY interface to interact with USB GEN-II and USB 3.x PHY that is part of the Intel network SOC. +config PHY_CAN_TRANSCEIVER + tristate "CAN transceiver PHY" + select GENERIC_PHY + help + This option enables support for CAN transceivers as a PHY. This + driver provides function for putting the transceivers in various + functional modes using gpios and sets the attribute max link + rate, for CAN drivers. + source "drivers/phy/allwinner/Kconfig" source "drivers/phy/amlogic/Kconfig" source "drivers/phy/broadcom/Kconfig" diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile index adac1b1a39d1..01e9efffc726 100644 --- a/drivers/phy/Makefile +++ b/drivers/phy/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_GENERIC_PHY) += phy-core.o obj-$(CONFIG_GENERIC_PHY_MIPI_DPHY) += phy-core-mipi-dphy.o +obj-$(CONFIG_PHY_CAN_TRANSCEIVER) += phy-can-transceiver.o obj-$(CONFIG_PHY_LPC18XX_USB_OTG) += phy-lpc18xx-usb-otg.o obj-$(CONFIG_PHY_XGENE) += phy-xgene.o obj-$(CONFIG_PHY_PISTACHIO_USB) += phy-pistachio-usb.o diff --git a/drivers/phy/phy-can-transceiver.c b/drivers/phy/phy-can-transceiver.c new file mode 100644 index 000000000000..c2cb93b4df71 --- /dev/null +++ b/drivers/phy/phy-can-transceiver.c @@ -0,0 +1,146 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * phy-can-transceiver.c - phy driver for CAN transceivers + * + * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com + * + */ +#include +#include +#include +#include +#include + +struct can_transceiver_data { + u32 flags; +#define CAN_TRANSCEIVER_STB_PRESENT BIT(0) +#define CAN_TRANSCEIVER_EN_PRESENT BIT(1) +}; + +struct can_transceiver_phy { + struct phy *generic_phy; + struct gpio_desc *standby_gpio; + struct gpio_desc *enable_gpio; +}; + +/* Power on function */ +static int can_transceiver_phy_power_on(struct phy *phy) +{ + struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); + + if (can_transceiver_phy->standby_gpio) + gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0); + if (can_transceiver_phy->enable_gpio) + gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1); + + return 0; +} + +/* Power off function */ +static int can_transceiver_phy_power_off(struct phy *phy) +{ + struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); + + if (can_transceiver_phy->standby_gpio) + gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1); + if (can_transceiver_phy->enable_gpio) + gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0); + + return 0; +} + +static const struct phy_ops can_transceiver_phy_ops = { + .power_on = can_transceiver_phy_power_on, + .power_off = can_transceiver_phy_power_off, + .owner = THIS_MODULE, +}; + +static const struct can_transceiver_data tcan1042_drvdata = { + .flags = CAN_TRANSCEIVER_STB_PRESENT, +}; + +static const struct can_transceiver_data tcan1043_drvdata = { + .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_EN_PRESENT, +}; + +static const struct of_device_id can_transceiver_phy_ids[] = { + { + .compatible = "ti,tcan1042", + .data = &tcan1042_drvdata + }, + { + .compatible = "ti,tcan1043", + .data = &tcan1043_drvdata + }, + { } +}; +MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids); + +static int can_transceiver_phy_probe(struct platform_device *pdev) +{ + struct phy_provider *phy_provider; + struct device *dev = &pdev->dev; + struct can_transceiver_phy *can_transceiver_phy; + const struct can_transceiver_data *drvdata; + const struct of_device_id *match; + struct phy *phy; + struct gpio_desc *standby_gpio; + struct gpio_desc *enable_gpio; + u32 max_bitrate = 0; + + can_transceiver_phy = devm_kzalloc(dev, sizeof(struct can_transceiver_phy), GFP_KERNEL); + if (!can_transceiver_phy) + return -ENOMEM; + + match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node); + drvdata = match->data; + + phy = devm_phy_create(dev, dev->of_node, + &can_transceiver_phy_ops); + if (IS_ERR(phy)) { + dev_err(dev, "failed to create can transceiver phy\n"); + return PTR_ERR(phy); + } + + device_property_read_u32(dev, "max-bitrate", &max_bitrate); + if (!max_bitrate) + dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n"); + phy->attrs.max_link_rate = max_bitrate; + + can_transceiver_phy->generic_phy = phy; + + if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) { + standby_gpio = devm_gpiod_get(dev, "standby", GPIOD_OUT_HIGH); + if (IS_ERR(standby_gpio)) + return PTR_ERR(standby_gpio); + can_transceiver_phy->standby_gpio = standby_gpio; + } + + if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) { + enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW); + if (IS_ERR(enable_gpio)) + return PTR_ERR(enable_gpio); + can_transceiver_phy->enable_gpio = enable_gpio; + } + + phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy); + + phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate); + + return PTR_ERR_OR_ZERO(phy_provider); +} + +static struct platform_driver can_transceiver_phy_driver = { + .probe = can_transceiver_phy_probe, + .driver = { + .name = "can-transceiver-phy", + .of_match_table = can_transceiver_phy_ids, + }, +}; + +module_platform_driver(can_transceiver_phy_driver); + +MODULE_AUTHOR("Faiz Abbas "); +MODULE_AUTHOR("Aswath Govindraju "); +MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver"); +MODULE_LICENSE("GPL v2");