From mboxrd@z Thu Jan 1 00:00:00 1970 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=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 C5596C43381 for ; Thu, 28 Feb 2019 20:14:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 732BB218B0 for ; Thu, 28 Feb 2019 20:14:27 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ti.com header.i=@ti.com header.b="vkWVTQC/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387797AbfB1UOZ (ORCPT ); Thu, 28 Feb 2019 15:14:25 -0500 Received: from lelv0142.ext.ti.com ([198.47.23.249]:53080 "EHLO lelv0142.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726088AbfB1UOY (ORCPT ); Thu, 28 Feb 2019 15:14:24 -0500 Received: from fllv0035.itg.ti.com ([10.64.41.0]) by lelv0142.ext.ti.com (8.15.2/8.15.2) with ESMTP id x1SKEEcg088377; Thu, 28 Feb 2019 14:14:14 -0600 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1551384854; bh=LnIfJeMRo4/U0RK7N3SjcEwnwcp1i51OKZNAXdkR06U=; h=Subject:To:CC:References:From:Date:In-Reply-To; b=vkWVTQC/ikLXr2ciN4QzKErPU+Sc4Yk+hT8Gk2Lf/0Vlf0NVJPUtkTcrbunTidW/D BqdE+NP/dTcrrS2DK7qI77L0KByC27Kv7YNJMCpAXyamuKl07tIFq75sN758k+mz78 WlKdqvdg7LTrYmxxMKVoSOaa4sQhqH3RrYEtCoFw= Received: from DLEE112.ent.ti.com (dlee112.ent.ti.com [157.170.170.23]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id x1SKEEV2103822 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 28 Feb 2019 14:14:14 -0600 Received: from DLEE103.ent.ti.com (157.170.170.33) by DLEE112.ent.ti.com (157.170.170.23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1591.10; Thu, 28 Feb 2019 14:14:13 -0600 Received: from dlep32.itg.ti.com (157.170.170.100) by DLEE103.ent.ti.com (157.170.170.33) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1591.10 via Frontend Transport; Thu, 28 Feb 2019 14:14:13 -0600 Received: from [172.22.64.21] (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id x1SKEDFY015402; Thu, 28 Feb 2019 14:14:13 -0600 Subject: Re: [PATCH v5 5/5] can: tcan4x5x: Add tcan4x5x driver to the kernel To: Wolfgang Grandegger , , CC: , , References: <20190214182754.30721-1-dmurphy@ti.com> <20190214182754.30721-6-dmurphy@ti.com> <6b5ce732-bce1-7e35-2bf4-a1000bfc9208@grandegger.com> From: Dan Murphy Message-ID: Date: Thu, 28 Feb 2019 14:14:05 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.2 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 7bit X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Wolfgang On 2/28/19 2:07 PM, Wolfgang Grandegger wrote: > > Am 28.02.19 um 19:03 schrieb Dan Murphy: >> >> Wolfgang >> >> On 2/28/19 11:50 AM, Wolfgang Grandegger wrote: >>> >>> >>> Am 14.02.19 um 19:27 schrieb Dan Murphy: >>>> Add the TCAN4x5x SPI CAN driver. This device >>>> uses the Bosch MCAN IP core along with a SPI >>>> interface map. Leverage the MCAN common core >>>> code to manage the MCAN IP. >>>> >>>> This device has a special method to indicate a >>>> write/read operation on the data payload. >>> >>> Please expand the text to approx. 72 lines.>> >> >> 72 lines or characters? > > Characters, of course! > OK. Just clarifying. I did not think you were asking me to write a book here >>>> Signed-off-by: Dan Murphy >>>> --- >>>> >>>> v5 - Changes to accomodate previous patches for functionality - https://lore.kernel.org/patchwork/patch/1033096/ >>>> >>>> drivers/net/can/m_can/Kconfig | 6 + >>>> drivers/net/can/m_can/Makefile | 1 + >>>> drivers/net/can/m_can/tcan4x5x.c | 531 +++++++++++++++++++++++++++++++ >>>> 3 files changed, 538 insertions(+) >>>> create mode 100644 drivers/net/can/m_can/tcan4x5x.c >>>> >>>> diff --git a/drivers/net/can/m_can/Kconfig b/drivers/net/can/m_can/Kconfig >>>> index 66e31022a5fa..6c0ab4703fb7 100644 >>>> --- a/drivers/net/can/m_can/Kconfig >>>> +++ b/drivers/net/can/m_can/Kconfig >>>> @@ -9,3 +9,9 @@ config CAN_M_CAN_PLATFORM >>>> depends on CAN_M_CAN >>>> ---help--- >>>> Say Y here if you want to support for Bosch M_CAN controller. >>>> + >>>> +config CAN_M_CAN_TCAN4X5X >>>> + depends on CAN_M_CAN >>>> + tristate "TCAN4X5X M_CAN device" >>>> + ---help--- >>>> + Say Y here if you want to support for TI M_CAN controller. >>> >>> Could yo please be a bit more verbose here. >> >> ACK >> >>> >>>> diff --git a/drivers/net/can/m_can/Makefile b/drivers/net/can/m_can/Makefile >>>> index 057bbcdb3c74..e77f0eccff97 100644 >>>> --- a/drivers/net/can/m_can/Makefile >>>> +++ b/drivers/net/can/m_can/Makefile >>>> @@ -4,3 +4,4 @@ >>>> >>>> obj-$(CONFIG_CAN_M_CAN) += m_can.o >>>> obj-$(CONFIG_CAN_M_CAN_PLATFORM) += m_can_platform.o >>>> +obj-$(CONFIG_CAN_M_CAN_TCAN4X5X) += tcan4x5x.o >>>> diff --git a/drivers/net/can/m_can/tcan4x5x.c b/drivers/net/can/m_can/tcan4x5x.c >>>> new file mode 100644 >>>> index 000000000000..606cd1925009 >>>> --- /dev/null >>>> +++ b/drivers/net/can/m_can/tcan4x5x.c >>>> @@ -0,0 +1,531 @@ >>>> +// SPDX-License-Identifier: GPL-2.0 >>>> +// SPI to CAN driver for the Texas Instruments TCAN4x5x >>>> +// Copyright (C) 2018-19 Texas Instruments Incorporated - http://www.ti.com/ >>>> + >>>> +#include >>>> +#include >>>> + >>>> +#include >>>> +#include >>>> + >>>> +#include "m_can.h" >>>> + >>>> +#define DEVICE_NAME "tcan4x5x" >>>> +#define TCAN4X5X_EXT_CLK_DEF 40000000 >>>> + >>>> +#define TCAN4X5X_DEV_ID0 0x00 >>>> +#define TCAN4X5X_DEV_ID1 0x04 >>>> +#define TCAN4X5X_REV 0x08 >>>> +#define TCAN4X5X_STATUS 0x0C >>>> +#define TCAN4X5X_ERROR_STATUS 0x10 >>>> +#define TCAN4X5X_CONTROL 0x14 >>>> + >>>> +#define TCAN4X5X_CONFIG 0x800 >>>> +#define TCAN4X5X_TS_PRESCALE 0x804 >>>> +#define TCAN4X5X_TEST_REG 0x808 >>>> +#define TCAN4X5X_INT_FLAGS 0x820 >>>> +#define TCAN4X5X_MCAN_INT_REG 0x824 >>>> +#define TCAN4X5X_INT_EN 0x830 >>>> + >>>> + >>>> +/* Interrupt bits */ >>>> +#define TCAN4X5X_CANBUSTERMOPEN_INT_EN BIT(30) >>>> +#define TCAN4X5X_CANHCANL_INT_EN BIT(29) >>>> +#define TCAN4X5X_CANHBAT_INT_EN BIT(28) >>>> +#define TCAN4X5X_CANLGND_INT_EN BIT(27) >>>> +#define TCAN4X5X_CANBUSOPEN_INT_EN BIT(26) >>>> +#define TCAN4X5X_CANBUSGND_INT_EN BIT(25) >>>> +#define TCAN4X5X_CANBUSBAT_INT_EN BIT(24) >>>> +#define TCAN4X5X_UVSUP_INT_EN BIT(22) >>>> +#define TCAN4X5X_UVIO_INT_EN BIT(21) >>>> +#define TCAN4X5X_TSD_INT_EN BIT(19) >>>> +#define TCAN4X5X_ECCERR_INT_EN BIT(16) >>>> +#define TCAN4X5X_CANINT_INT_EN BIT(15) >>>> +#define TCAN4X5X_LWU_INT_EN BIT(14) >>>> +#define TCAN4X5X_CANSLNT_INT_EN BIT(10) >>>> +#define TCAN4X5X_CANDOM_INT_EN BIT(8) >>>> +#define TCAN4X5X_CANBUS_ERR_INT_EN BIT(5) >>>> +#define TCAN4X5X_BUS_FAULT BIT(4) >>>> +#define TCAN4X5X_MCAN_INT BIT(1) >>>> +#define TCAN4X5X_ENABLE_TCAN_INT (TCAN4X5X_MCAN_INT | \ >>>> + TCAN4X5X_BUS_FAULT | \ >>>> + TCAN4X5X_CANBUS_ERR_INT_EN | \ >>>> + TCAN4X5X_CANINT_INT_EN) >>>> + >>>> +/* MCAN Interrupt bits */ >>>> +#define TCAN4X5X_MCAN_IR_ARA BIT(29) >>>> +#define TCAN4X5X_MCAN_IR_PED BIT(28) >>>> +#define TCAN4X5X_MCAN_IR_PEA BIT(27) >>>> +#define TCAN4X5X_MCAN_IR_WD BIT(26) >>>> +#define TCAN4X5X_MCAN_IR_BO BIT(25) >>>> +#define TCAN4X5X_MCAN_IR_EW BIT(24) >>>> +#define TCAN4X5X_MCAN_IR_EP BIT(23) >>>> +#define TCAN4X5X_MCAN_IR_ELO BIT(22) >>>> +#define TCAN4X5X_MCAN_IR_BEU BIT(21) >>>> +#define TCAN4X5X_MCAN_IR_BEC BIT(20) >>>> +#define TCAN4X5X_MCAN_IR_DRX BIT(19) >>>> +#define TCAN4X5X_MCAN_IR_TOO BIT(18) >>>> +#define TCAN4X5X_MCAN_IR_MRAF BIT(17) >>>> +#define TCAN4X5X_MCAN_IR_TSW BIT(16) >>>> +#define TCAN4X5X_MCAN_IR_TEFL BIT(15) >>>> +#define TCAN4X5X_MCAN_IR_TEFF BIT(14) >>>> +#define TCAN4X5X_MCAN_IR_TEFW BIT(13) >>>> +#define TCAN4X5X_MCAN_IR_TEFN BIT(12) >>>> +#define TCAN4X5X_MCAN_IR_TFE BIT(11) >>>> +#define TCAN4X5X_MCAN_IR_TCF BIT(10) >>>> +#define TCAN4X5X_MCAN_IR_TC BIT(9) >>>> +#define TCAN4X5X_MCAN_IR_HPM BIT(8) >>>> +#define TCAN4X5X_MCAN_IR_RF1L BIT(7) >>>> +#define TCAN4X5X_MCAN_IR_RF1F BIT(6) >>>> +#define TCAN4X5X_MCAN_IR_RF1W BIT(5) >>>> +#define TCAN4X5X_MCAN_IR_RF1N BIT(4) >>>> +#define TCAN4X5X_MCAN_IR_RF0L BIT(3) >>>> +#define TCAN4X5X_MCAN_IR_RF0F BIT(2) >>>> +#define TCAN4X5X_MCAN_IR_RF0W BIT(1) >>>> +#define TCAN4X5X_MCAN_IR_RF0N BIT(0) >>>> +#define TCAN4X5X_ENABLE_MCAN_INT (TCAN4X5X_MCAN_IR_TC | \ >>>> + TCAN4X5X_MCAN_IR_RF0N | \ >>>> + TCAN4X5X_MCAN_IR_RF1N | \ >>>> + TCAN4X5X_MCAN_IR_RF0F | \ >>>> + TCAN4X5X_MCAN_IR_RF1F) >>>> +#define TCAN4X5X_MRAM_START 0x8000 >>>> +#define TCAN4X5X_MCAN_OFFSET 0x1000 >>>> +#define TCAN4X5X_MAX_REGISTER 0x8fff >>>> + >>>> +#define TCAN4X5X_CLEAR_ALL_INT 0xffffffff >>>> +#define TCAN4X5X_SET_ALL_INT 0xffffffff >>>> + >>>> +#define TCAN4X5X_WRITE_CMD (0x61 << 24) >>>> +#define TCAN4X5X_READ_CMD (0x41 << 24) >>>> + >>>> +#define TCAN4X5X_MODE_SEL_MASK (BIT(7) | BIT(6)) >>>> +#define TCAN4X5X_MODE_SLEEP 0x00 >>>> +#define TCAN4X5X_MODE_STANDBY BIT(6) >>>> +#define TCAN4X5X_MODE_NORMAL BIT(7) >>>> + >>>> +#define TCAN4X5X_SW_RESET BIT(2) >>>> + >>>> +#define TCAN4X5X_MCAN_CONFIGURED BIT(5) >>>> +#define TCAN4X5X_WATCHDOG_EN BIT(3) >>>> +#define TCAN4X5X_WD_60_MS_TIMER 0 >>>> +#define TCAN4X5X_WD_600_MS_TIMER BIT(28) >>>> +#define TCAN4X5X_WD_3_S_TIMER BIT(29) >>>> +#define TCAN4X5X_WD_6_S_TIMER (BIT(28) | BIT(29)) >>>> + >>>> +struct tcan4x5x_priv { >>>> + struct regmap *regmap; >>>> + struct spi_device *spi; >>>> + struct mutex tcan4x5x_lock; /* SPI device lock */ >>>> + >>>> + struct m_can_classdev *mcan_dev; >>>> + >>>> + struct gpio_desc *reset_gpio; >>>> + struct gpio_desc *interrupt_gpio; >>>> + struct gpio_desc *device_wake_gpio; >>>> + struct gpio_desc *device_state_gpio; >>>> + struct regulator *power; >>>> + >>>> + /* Register based ip */ >>>> + int mram_start; >>>> + int reg_offset; >>>> +}; >>>> + >>>> +static struct can_bittiming_const tcan4x5x_bittiming_const = { >>>> + .name = DEVICE_NAME, >>>> + .tseg1_min = 2, >>>> + .tseg1_max = 31, >>>> + .tseg2_min = 2, >>>> + .tseg2_max = 16, >>>> + .sjw_max = 16, >>>> + .brp_min = 1, >>>> + .brp_max = 32, >>>> + .brp_inc = 1, >>>> +}; >>>> + >>>> +static struct can_bittiming_const tcan4x5x_data_bittiming_const = { >>>> + .name = DEVICE_NAME, >>>> + .tseg1_min = 1, >>>> + .tseg1_max = 32, >>>> + .tseg2_min = 1, >>>> + .tseg2_max = 16, >>>> + .sjw_max = 16, >>>> + .brp_min = 1, >>>> + .brp_max = 32, >>>> + .brp_inc = 1, >>>> +}; >>>> + >>>> +static void tcan4x5x_check_wake(struct tcan4x5x_priv *priv) >>>> +{ >>>> + int wake_state = 0; >>>> + >>>> + if (priv->device_state_gpio) >>>> + wake_state = gpiod_get_value(priv->device_state_gpio); >>>> + >>>> + if (priv->device_wake_gpio && wake_state) { >>>> + gpiod_set_value(priv->device_wake_gpio, 1); >>>> + udelay(100); >>> >>> Do you need the setting above? >>> >> >> Do you mean do I need to set the reset line then delay? > > I mean, do you need to set the gpio value to 1 at the beginning? Is 0->1 > not enough? > The data sheet indicates it needs to see a rising edge to wake up. The hw engineer asked me to put it this way. But after digging into the data sheet I am not seeing the HW reason. I will remove it and see if there is any effect on the operation. If we need it I will add a comment why. >> >>>> + gpiod_set_value(priv->device_wake_gpio, 0); >>>> + udelay(100); >>>> + gpiod_set_value(priv->device_wake_gpio, 1); >>>> + } >>>> +} >>>> + >>>> +static int regmap_spi_gather_write(void *context, const void *reg, >>>> + size_t reg_len, const void *val, >>>> + size_t val_len) >>>> +{ >>>> + struct device *dev = context; >>>> + struct spi_device *spi = to_spi_device(dev); >>>> + struct spi_message m; >>>> + u32 addr; >>>> + struct spi_transfer t[2] = {{ .tx_buf = &addr, .len = reg_len, .cs_change = 0,}, >>>> + { .tx_buf = val, .len = val_len, },}; >>> >>> struct spi_transfer t[2] = { >>> {.tx_buf = &addr, .len = reg_len, .cs_change = 0,}, >>> {.tx_buf = val, .len = val_len,}, >>> }; >>> >>> >> >> I am assuming LTL issue here. > > LTL means? I just reformatted the declaration. > Line to Long. But I changed it so it looks better. >> >>>> + >>>> + addr = TCAN4X5X_WRITE_CMD | (*((u16 *)reg) << 8) | val_len >> 3; >>> >>> >> >> There is nothing here > > It's OK. > >> >>> >>>> + >>>> + spi_message_init(&m); >>>> + spi_message_add_tail(&t[0], &m); >>>> + spi_message_add_tail(&t[1], &m); >>>> + >>>> + return spi_sync(spi, &m); >>>> +} >>>> + >>>> +static int tcan4x5x_regmap_write(void *context, const void *data, size_t count) >>>> +{ >>>> + u16 *reg = (u16 *)(data); >>>> + const u32 *val = data + 4; >>>> + >>>> + return regmap_spi_gather_write(context, reg, 4, val, count); >>>> +} >>>> + >>>> +static int regmap_spi_async_write(void *context, >>>> + const void *reg, size_t reg_len, >>>> + const void *val, size_t val_len, >>>> + struct regmap_async *a) >>>> +{ >>>> + return -ENOTSUPP; >>>> +} >>>> + >>>> +static struct regmap_async *regmap_spi_async_alloc(void) >>>> +{ >>>> + return NULL; >>>> +} >>>> + >>>> +static int tcan4x5x_regmap_read(void *context, >>>> + const void *reg, size_t reg_size, >>>> + void *val, size_t val_size) >>>> +{ >>>> + struct device *dev = context; >>>> + struct spi_device *spi = to_spi_device(dev); >>>> + >>>> + u32 addr = TCAN4X5X_READ_CMD | (*((u16 *)reg) << 8) | val_size >> 2; >>>> + >>>> + return spi_write_then_read(spi, &addr, reg_size, (u32 *)val, val_size); >>>> +} >>>> + >>>> +static struct regmap_bus tcan4x5x_bus = { >>>> + .write = tcan4x5x_regmap_write, >>>> + .gather_write = regmap_spi_gather_write, >>>> + .async_write = regmap_spi_async_write, >>>> + .async_alloc = regmap_spi_async_alloc, >>>> + .read = tcan4x5x_regmap_read, >>>> + .read_flag_mask = 0x00, >>>> + .reg_format_endian_default = REGMAP_ENDIAN_NATIVE, >>>> + .val_format_endian_default = REGMAP_ENDIAN_NATIVE, >>>> +}; >>>> + >>>> +static u32 tcan4x5x_read_reg(struct m_can_classdev *m_can_class, int reg) >>>> +{ >>>> + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; >>>> + u32 val; >>>> + >>>> + tcan4x5x_check_wake(priv); >>>> + >>>> + regmap_read(priv->regmap, priv->reg_offset + reg, &val); >>>> + >>>> + return val; >>>> +} >>>> + >>>> +static u32 tcan4x5x_read_fifo(struct m_can_classdev *m_can_class, >>>> + int addr_offset) >>>> +{ >>>> + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; >>>> + u32 val; >>>> + >>>> + tcan4x5x_check_wake(priv); >>>> + >>>> + regmap_read(priv->regmap, priv->mram_start + addr_offset, &val); >>>> + >>>> + return val; >>>> +} >>>> + >>>> +static int tcan4x5x_write_reg(struct m_can_classdev *m_can_class, >>>> + int reg, int val) >>>> +{ >>>> + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; >>>> + >>>> + tcan4x5x_check_wake(priv); >>>> + >>>> + return regmap_write(priv->regmap, priv->reg_offset + reg, val); >>>> +} >>>> + >>>> +static int tcan4x5x_write_fifo(struct m_can_classdev *m_can_class, >>>> + int addr_offset, int val) >>>> +{ >>>> + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; >>>> + >>>> + tcan4x5x_check_wake(priv); >>>> + >>>> + return regmap_write(priv->regmap, priv->mram_start + addr_offset, val); >>>> +} >>>> + >>>> +static int tcan4x5x_power_enable(struct regulator *reg, int enable) >>>> +{ >>>> + if (IS_ERR_OR_NULL(reg)) >>>> + return 0; >>>> + >>>> + if (enable) >>>> + return regulator_enable(reg); >>>> + else >>>> + return regulator_disable(reg); >>>> +} >>>> + >>>> +static int tcan4x5x_write_tcan_reg(struct m_can_classdev *m_can_class, >>>> + int reg, int val) >>>> +{ >>>> + struct tcan4x5x_priv *priv = (struct tcan4x5x_priv *)m_can_class->device_data; >>>> + >>>> + tcan4x5x_check_wake(priv); >>>> + >>>> + return regmap_write(priv->regmap, reg, val); >>>> +} >>>> + >>>> +static int tcan4x5x_clear_interrupts(struct m_can_classdev *class_dev) >>>> +{ >>>> + struct tcan4x5x_priv *tcan4x5x = (struct tcan4x5x_priv *)class_dev->device_data; >>>> + int ret; >>>> + >>>> + tcan4x5x_check_wake(tcan4x5x); >>>> + >>>> + ret = tcan4x5x_write_tcan_reg(class_dev, TCAN4X5X_STATUS, >>>> + TCAN4X5X_CLEAR_ALL_INT); >>>> + if (ret) >>>> + return -EIO; >>> >>> Does "ret" not return a proper error code? >> >> I can change it to ret. > > Browsing some kernel code, returning "ret" seems the usual approach > (apart from ignoring the return code). > Changed >> >>> >>>> + >>>> + ret = tcan4x5x_write_tcan_reg(class_dev, TCAN4X5X_MCAN_INT_REG, >>>> + TCAN4X5X_ENABLE_MCAN_INT); >>>> + if (ret) >>>> + return -EIO; >>>> + >>>> + ret = tcan4x5x_write_tcan_reg(class_dev, TCAN4X5X_INT_FLAGS, >>>> + TCAN4X5X_CLEAR_ALL_INT); >>>> + if (ret) >>>> + return -EIO; >>>> + >>>> + >>>> + ret = tcan4x5x_write_tcan_reg(class_dev, TCAN4X5X_ERROR_STATUS, >>>> + TCAN4X5X_CLEAR_ALL_INT); >>>> + if (ret) >>>> + return -EIO; >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int tcan4x5x_init(struct m_can_classdev *class_dev) >>>> +{ >>>> + struct tcan4x5x_priv *tcan4x5x = (struct tcan4x5x_priv *)class_dev->device_data; >>>> + int ret; >>>> + >>>> + tcan4x5x_check_wake(tcan4x5x); >>>> + >>>> + ret = tcan4x5x_clear_interrupts(class_dev); >>>> + if (ret) >>>> + return ret; >>>> + >>>> + ret = tcan4x5x_write_tcan_reg(class_dev, TCAN4X5X_INT_EN, >>>> + TCAN4X5X_ENABLE_TCAN_INT); >>>> + if (ret) >>>> + return -EIO; >>>> + >>>> + ret = regmap_update_bits(tcan4x5x->regmap, TCAN4X5X_CONFIG, >>>> + TCAN4X5X_MODE_SEL_MASK, TCAN4X5X_MODE_NORMAL); >>>> + if (ret) >>>> + return -EIO; >> >> Same comment as above >> >>>> + >>>> + /* Zero out the MCAN buffers */ >>>> + m_can_init_ram(class_dev); >>>> + >>>> + return ret; >>>> +} >>>> + >>>> +static int tcan4x5x_parse_config(struct m_can_classdev *class_dev) >>>> +{ >>>> + struct tcan4x5x_priv *tcan4x5x = (struct tcan4x5x_priv *)class_dev->device_data; >>>> + >>>> + tcan4x5x->reset_gpio = devm_gpiod_get_optional(class_dev->dev, >>>> + "reset", GPIOD_OUT_LOW); >>>> + if (IS_ERR(tcan4x5x->reset_gpio)) >>>> + tcan4x5x->reset_gpio = NULL; >>>> + >>>> + tcan4x5x->device_wake_gpio = devm_gpiod_get_optional(class_dev->dev, >>>> + "device-wake", >>>> + GPIOD_OUT_HIGH); >>>> + if (IS_ERR(tcan4x5x->device_wake_gpio)) >>>> + tcan4x5x->device_wake_gpio = NULL; >>>> + >>>> + tcan4x5x->device_state_gpio = devm_gpiod_get_optional(class_dev->dev, >>>> + "device-state", >>>> + GPIOD_IN); >>>> + if (IS_ERR(tcan4x5x->device_state_gpio)) >>>> + tcan4x5x->device_state_gpio = NULL; >>>> + >>>> + tcan4x5x->interrupt_gpio = devm_gpiod_get(class_dev->dev, >>>> + "data-ready", GPIOD_IN); >>>> + if (IS_ERR(tcan4x5x->interrupt_gpio)) { >>>> + dev_err(class_dev->dev, "data-ready gpio not defined\n"); >>>> + return -EINVAL; >>>> + } >>>> + >>>> + class_dev->net->irq = gpiod_to_irq(tcan4x5x->interrupt_gpio); >>>> + >>>> + tcan4x5x->power = devm_regulator_get_optional(class_dev->dev, >>>> + "vsup"); >>>> + if (PTR_ERR(tcan4x5x->power) == -EPROBE_DEFER) >>>> + return -EPROBE_DEFER; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static const struct regmap_config tcan4x5x_regmap = { >>>> + .reg_bits = 32, >>>> + .val_bits = 32, >>>> + .cache_type = REGCACHE_NONE, >>>> + .max_register = TCAN4X5X_MAX_REGISTER, >>>> +}; >>>> + >>>> +static struct m_can_ops tcan4x5x_ops = { >>>> + .device_init = tcan4x5x_init, >>>> + .read_reg = tcan4x5x_read_reg, >>>> + .write_reg = tcan4x5x_write_reg, >>>> + .write_fifo = tcan4x5x_write_fifo, >>>> + .read_fifo = tcan4x5x_read_fifo, >>>> + .clr_dev_interrupts = tcan4x5x_clear_interrupts, >>>> +}; >>>> + >>>> +static int tcan4x5x_can_probe(struct spi_device *spi) >>>> +{ >>>> + struct tcan4x5x_priv *priv; >>>> + struct m_can_classdev *mcan_class; >>>> + int freq, ret; >>>> + >>>> + mcan_class = m_can_class_allocate_dev(&spi->dev); >>>> + priv = devm_kzalloc(&spi->dev, sizeof(*priv), GFP_KERNEL); >>>> + if (!priv) >>>> + return -ENOMEM; >>>> + >>>> + mcan_class->device_data = priv; >>>> + >>>> + m_can_class_get_clocks(mcan_class); >>>> + if (IS_ERR(mcan_class->cclk)) { >>>> + dev_err(&spi->dev, "no CAN clock source defined\n"); >>>> + freq = TCAN4X5X_EXT_CLK_DEF; >>>> + } else { >>>> + freq = clk_get_rate(mcan_class->cclk); >>>> + } >>>> + >>>> + /* Sanity check */ >>>> + if (freq < 20000000 || freq > TCAN4X5X_EXT_CLK_DEF) >>>> + return -ERANGE; >>>> + >>>> + priv->reg_offset = TCAN4X5X_MCAN_OFFSET; >>>> + priv->mram_start = TCAN4X5X_MRAM_START; >>>> + priv->spi = spi; >>>> + priv->mcan_dev = mcan_class; >>>> + >>>> + mcan_class->pm_clock_support = 0; >>>> + mcan_class->can.clock.freq = freq; >>>> + mcan_class->dev = &spi->dev; >>>> + mcan_class->ops = &tcan4x5x_ops; >>>> + mcan_class->is_peripherial = true; >>>> + mcan_class->bit_timing = &tcan4x5x_bittiming_const; >>>> + mcan_class->data_timing = &tcan4x5x_data_bittiming_const; >>>> + >>>> + spi_set_drvdata(spi, priv); >>>> + >>>> + ret = tcan4x5x_parse_config(mcan_class); >>>> + if (ret) >>>> + goto out_clk; >>>> + >>>> + /* Configure the SPI bus */ >>>> + spi->bits_per_word = 32; >>>> + ret = spi_setup(spi); >>>> + if (ret) >>>> + goto out_clk; >>>> + >>>> + priv->regmap = devm_regmap_init(&spi->dev, &tcan4x5x_bus, >>>> + &spi->dev, &tcan4x5x_regmap); >>>> + >>>> + mutex_init(&priv->tcan4x5x_lock); >>>> + >>>> + tcan4x5x_power_enable(priv->power, 1); >>>> + >>>> + ret = m_can_class_register(mcan_class); >>>> + if (ret) >>>> + goto reg_err; >>> >>> out_power? >>> >> >> Not sure what you are asking? > > "reg_err" stands for what? Above you use "out_clk" to disable clock > settings. Therefore "out_power" does make sense to me (or something > similar). Next time I will be a bit more verbose, sorry! > Yeah that makes more sense. reg_err was registration error. >> >>>> + >>>> + netdev_info(mcan_class->net, "TCAN4X5X successfully initialized.\n"); >>>> + return 0; >>>> + >>>> +reg_err: >>>> + tcan4x5x_power_enable(priv->power, 0); >>>> +out_clk: >>>> + if (!IS_ERR(mcan_class->cclk)) { >>>> + clk_disable_unprepare(mcan_class->cclk); >>>> + clk_disable_unprepare(mcan_class->hclk); >>>> + } >>>> + >>>> + dev_err(&spi->dev, "Probe failed, err=%d\n", -ret); >>> >>> Just "ret" is fine! >>> >> >> Ack >> >>>> + return ret; >>>> +} >>>> + >>>> +static int tcan4x5x_can_remove(struct spi_device *spi) >>>> +{ >>>> + struct tcan4x5x_priv *priv = spi_get_drvdata(spi); >>>> + >>>> + tcan4x5x_power_enable(priv->power, 0); >>>> + >>>> + m_can_class_unregister(priv->mcan_dev); >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static const struct of_device_id tcan4x5x_of_match[] = { >>>> + { .compatible = "ti,tcan4x5x", }, >>>> + { } >>>> +}; >>>> +MODULE_DEVICE_TABLE(of, tcan4x5x_of_match); >>>> + >>>> +static const struct spi_device_id tcan4x5x_id_table[] = { >>>> + { >>>> + .name = "tcan4x5x", >>>> + .driver_data = 0, >>>> + }, >>>> + { } >>>> +}; >>>> +MODULE_DEVICE_TABLE(spi, tcan4x5x_id_table); >>>> + >>>> +static struct spi_driver tcan4x5x_can_driver = { >>>> + .driver = { >>>> + .name = DEVICE_NAME, >>>> + .of_match_table = tcan4x5x_of_match, >>>> + .pm = NULL, >>>> + }, >>>> + .id_table = tcan4x5x_id_table, >>>> + .probe = tcan4x5x_can_probe, >>>> + .remove = tcan4x5x_can_remove, >>>> +}; >>>> +module_spi_driver(tcan4x5x_can_driver); >>>> + >>>> +MODULE_AUTHOR("Dan Murphy "); >>>> +MODULE_DESCRIPTION("Texas Instruments TCAN4x5x CAN driver"); >>>> +MODULE_LICENSE("GPL v2"); >>>> >>> >>> The changes to the io-mapped driver look good and non-critical... time >>> to ask for beta-testers for the next version of the patch series. >>> >> >> OK. I also tested this here on one of our boards that use the iomapped code. > > I know, you are testing on a dra76x from? > > https://www.spinics.net/lists/linux-can/msg00886.html > > More testing would be nice. > OK. I know we will be testing both the io mapped and we have a couple customers using the TCAN code with this change. Dan > Wolfgang. > -- ------------------ Dan Murphy