Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751583AbbEGMdE (ORCPT ); Thu, 7 May 2015 08:33:04 -0400 Received: from kiutl.biot.com ([31.172.244.210]:58042 "EHLO kiutl.biot.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751303AbbEGMc6 (ORCPT ); Thu, 7 May 2015 08:32:58 -0400 From: Bert Vermeulen To: dwmw2@infradead.org, computersforpeace@gmail.com, linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Bert Vermeulen Subject: [PATCH v2] nand: Add NAND driver for Mikrotik RB4xx series boards Date: Thu, 7 May 2015 14:31:50 +0200 Message-Id: <1431001910-4004-1-git-send-email-bert@biot.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 15641 Lines: 595 The NAND chip containing the root filesystem is behind an SPI-connected CPLD. This driver uses the spi-rb4xx driver to communicate with the CPLD. The CPLD also acts as a GPIO expander: the ALE/CLE/NCE pins are set via CPLD commands. Some LEDs on the board are also accessed this way. Signed-off-by: Bert Vermeulen --- Changes in v2: - Fix Kconfig dependencies and description - Move NAND partitions into platform data - Use gpiod API with lookup table, and devm_ as needed - Code cleanup arch/mips/include/asm/mach-ath79/rb4xx.h | 44 +++ drivers/mtd/nand/Kconfig | 7 + drivers/mtd/nand/Makefile | 1 + drivers/mtd/nand/rb4xx_nand.c | 482 +++++++++++++++++++++++++++++++ 4 files changed, 534 insertions(+) create mode 100644 arch/mips/include/asm/mach-ath79/rb4xx.h create mode 100644 drivers/mtd/nand/rb4xx_nand.c diff --git a/arch/mips/include/asm/mach-ath79/rb4xx.h b/arch/mips/include/asm/mach-ath79/rb4xx.h new file mode 100644 index 0000000..667ea748 --- /dev/null +++ b/arch/mips/include/asm/mach-ath79/rb4xx.h @@ -0,0 +1,44 @@ +/* + * SPI driver definitions for the CPLD chip on the Mikrotik RB4xx boards + * + * Copyright (C) 2010 Gabor Juhos + * + * This file was based on the patches for Linux 2.6.27.39 published by + * MikroTik for their RouterBoard 4xx series devices. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include + +#define RB4XX_GPIO_CPLD_BASE 32 + +#define CPLD_GPIO_LED1 0 +#define CPLD_GPIO_LED2 2 +#define CPLD_GPIO_LED3 1 +#define CPLD_GPIO_LED4 3 +#define CPLD_GPIO_FAN 4 +#define CPLD_GPIO_ALE 5 +#define CPLD_GPIO_CLE 6 +#define CPLD_GPIO_NCE 7 +#define CPLD_GPIO_LED5 8 + +#define CPLD_NUM_GPIOS 9 + +#define CPLD_CFG_LED1 BIT(CPLD_GPIO_LED1) +#define CPLD_CFG_LED2 BIT(CPLD_GPIO_LED2) +#define CPLD_CFG_LED3 BIT(CPLD_GPIO_LED3) +#define CPLD_CFG_LED4 BIT(CPLD_GPIO_LED4) +#define CPLD_CFG_FAN BIT(CPLD_GPIO_FAN) +#define CPLD_CFG_ALE BIT(CPLD_GPIO_ALE) +#define CPLD_CFG_CLE BIT(CPLD_GPIO_CLE) +#define CPLD_CFG_NCE BIT(CPLD_GPIO_NCE) +#define CPLD_CFG_LED5 BIT(CPLD_GPIO_LED5) + +struct rb4xx_cpld_platform_data { + unsigned gpio_base; + struct flash_platform_data flash_data; +}; + diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 5897d8d..873639f 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -530,4 +530,11 @@ config MTD_NAND_HISI504 help Enables support for NAND controller on Hisilicon SoC Hip04. +config MTD_NAND_RB4XX + tristate "NAND flash driver for Mikrotik RB4xx series boards" + depends on MTD_NAND && SPI_RB4XX + help + Enables support for the NAND flash chip on Mikrotik Routerboard + RB4xx series. + endif # MTD_NAND diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile index 582bbd05..56dbd08 100644 --- a/drivers/mtd/nand/Makefile +++ b/drivers/mtd/nand/Makefile @@ -52,5 +52,6 @@ obj-$(CONFIG_MTD_NAND_XWAY) += xway_nand.o obj-$(CONFIG_MTD_NAND_BCM47XXNFLASH) += bcm47xxnflash/ obj-$(CONFIG_MTD_NAND_SUNXI) += sunxi_nand.o obj-$(CONFIG_MTD_NAND_HISI504) += hisi504_nand.o +obj-$(CONFIG_MTD_NAND_RB4XX) += rb4xx_nand.o nand-objs := nand_base.o nand_bbt.o nand_timings.o diff --git a/drivers/mtd/nand/rb4xx_nand.c b/drivers/mtd/nand/rb4xx_nand.c new file mode 100644 index 0000000..d61ee2b --- /dev/null +++ b/drivers/mtd/nand/rb4xx_nand.c @@ -0,0 +1,482 @@ +/* + * NAND flash driver for the MikroTik RouterBoard 4xx series + * + * Copyright (C) 2008-2011 Gabor Juhos + * Copyright (C) 2008 Imre Kaloz + * Copyright (C) 2015 Bert Vermeulen + * + * This file was based on the driver for Linux 2.6.22 published by + * MikroTik for their RouterBoard 4xx series devices. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include + +#include + +#define CPLD_CMD_WRITE_NAND 0x08 +#define CPLD_CMD_WRITE_CFG 0x09 +#define CPLD_CMD_READ_NAND 0x0a +#define CPLD_CMD_READ_FAST 0x0b +#define CPLD_CMD_LED5_ON 0x0c +#define CPLD_CMD_LED5_OFF 0x0d + +struct rb4xx_nand_info { + struct nand_chip chip; + struct mtd_info mtd; + struct spi_device *spi_dev; + struct gpio_desc *gpio_rdy; + struct gpio_desc *gpio_ale; + struct gpio_desc *gpio_cle; + struct gpio_desc *gpio_nce; +}; + +struct rb4xx_cpld { + struct spi_device *spi; + struct mutex lock; + struct gpio_chip chip; + unsigned int config; +}; + +/* + * We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader + * will not be able to find the kernel that we load. + */ +static struct nand_ecclayout rb4xx_nand_ecclayout = { + .eccbytes = 6, + .eccpos = { 8, 9, 10, 13, 14, 15 }, + .oobavail = 9, + .oobfree = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } } +}; + +static inline struct rb4xx_cpld *gpio_to_cpld(struct gpio_chip *chip) +{ + return container_of(chip, struct rb4xx_cpld, chip); +} + +static int rb4xx_cpld_write_cmd(struct rb4xx_cpld *cpld, unsigned char cmd) +{ + struct spi_transfer t; + struct spi_message m; + + spi_message_init(&m); + + memset(&t, 0, sizeof(t)); + t.tx_buf = &cmd; + t.len = sizeof(cmd); + spi_message_add_tail(&t, &m); + return spi_sync(cpld->spi, &m); +} + +static int rb4xx_cpld_write_cfg(struct rb4xx_cpld *cpld, unsigned char config) +{ + struct spi_transfer t; + struct spi_message m; + unsigned char cmd[2] = { + CPLD_CMD_WRITE_CFG, config + }; + + spi_message_init(&m); + + memset(&t, 0, sizeof(t)); + t.tx_buf = cmd; + t.len = sizeof(cmd); + spi_message_add_tail(&t, &m); + return spi_sync(cpld->spi, &m); +} + +static int rb4xx_cpld_change_cfg(struct rb4xx_cpld *cpld, u32 mask, u32 value) +{ + unsigned int config; + int ret; + + config = cpld->config & ~mask; + config |= value; + + if (mask & 0xff) { + ret = rb4xx_cpld_write_cfg(cpld, config); + if (ret) + return ret; + } + + if (mask & CPLD_CFG_LED5) { + if (value & CPLD_CFG_LED5) + ret = rb4xx_cpld_write_cmd(cpld, CPLD_CMD_LED5_ON); + else + ret = rb4xx_cpld_write_cmd(cpld, CPLD_CMD_LED5_OFF); + if (ret) + return ret; + } + + cpld->config = config; + + return 0; +} + +static int rb4xx_cpld_gpio_get(struct gpio_chip *chip, unsigned offset) +{ + struct rb4xx_cpld *cpld = gpio_to_cpld(chip); + int value; + + mutex_lock(&cpld->lock); + value = (cpld->config >> offset) & 1; + mutex_unlock(&cpld->lock); + + return value; +} + +static void rb4xx_cpld_gpio_set(struct gpio_chip *chip, + unsigned offset, int value) +{ + struct rb4xx_cpld *cpld = gpio_to_cpld(chip); + + mutex_lock(&cpld->lock); + rb4xx_cpld_change_cfg(cpld, (1 << offset), !!value << offset); + mutex_unlock(&cpld->lock); +} + +static int rb4xx_cpld_gpio_direction_input(struct gpio_chip *chip, + unsigned offset) +{ + return -EOPNOTSUPP; +} + +static int rb4xx_cpld_gpio_direction_output(struct gpio_chip *chip, + unsigned offset, int value) +{ + struct rb4xx_cpld *cpld = gpio_to_cpld(chip); + int ret; + + mutex_lock(&cpld->lock); + ret = rb4xx_cpld_change_cfg(cpld, (1 << offset), !!value << offset); + mutex_unlock(&cpld->lock); + + return ret; +} + +static int rb4xx_cpld_read(struct spi_device *spi, unsigned char *rx_buf, + unsigned len) +{ + struct spi_message m; + static const unsigned char cmd[2] = { + CPLD_CMD_READ_NAND, 0 + }; + struct spi_transfer t[2] = { + { + .tx_buf = &cmd, + .len = sizeof(cmd), + }, { + .rx_buf = rx_buf, + .len = len, + }, + }; + + 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 rb4xx_cpld_write(struct spi_device *spi, const u8 *buf, int len) +{ + struct spi_message m; + static const unsigned char cmd = CPLD_CMD_WRITE_NAND; + struct spi_transfer t[3] = { + { + .tx_buf = &cmd, + .len = sizeof(cmd), + }, { + .tx_buf = buf, + .len = len, + .tx_nbits = SPI_NBITS_DUAL, + }, { + .len = 1, + .tx_nbits = SPI_NBITS_DUAL, + }, + }; + + spi_message_init(&m); + spi_message_add_tail(&t[0], &m); + spi_message_add_tail(&t[1], &m); + spi_message_add_tail(&t[2], &m); + return spi_sync(spi, &m); +} + +static int rb4xx_nand_dev_ready(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd->priv; + struct rb4xx_nand_info *info = chip->priv; + return gpiod_get_value_cansleep(info->gpio_rdy); +} + +static void rb4xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, + unsigned int ctrl) +{ + struct nand_chip *chip = mtd->priv; + struct rb4xx_nand_info *info = chip->priv; + u8 data = cmd; + int ret; + + if (ctrl & NAND_CTRL_CHANGE) { + gpiod_set_value_cansleep(info->gpio_cle, + (ctrl & NAND_CLE) ? 1 : 0); + gpiod_set_value_cansleep(info->gpio_ale, + (ctrl & NAND_ALE) ? 1 : 0); + gpiod_set_value_cansleep(info->gpio_nce, + (ctrl & NAND_NCE) ? 0 : 1); + } + + if (cmd != NAND_CMD_NONE) { + ret = rb4xx_cpld_write(info->spi_dev, &data, 1); + if (ret) + pr_err("rb4xx_nand: write cmd failed, error %d\n", ret); + } +} + +static unsigned char rb4xx_nand_read_byte(struct mtd_info *mtd) +{ + struct nand_chip *chip = mtd->priv; + struct rb4xx_nand_info *info = chip->priv; + unsigned char data; + int ret; + + ret = rb4xx_cpld_read(info->spi_dev, &data, 1); + if (ret) { + pr_err("rb4xx_nand: read data failed, error %d\n", ret); + return 0xff; + } + + return data; +} + +static void rb4xx_nand_write_buf(struct mtd_info *mtd, const unsigned char *buf, + int len) +{ + struct nand_chip *chip = mtd->priv; + struct rb4xx_nand_info *info = chip->priv; + int ret; + + ret = rb4xx_cpld_write(info->spi_dev, buf, len); + if (ret) + pr_err("rb4xx_nand: write buf failed, error %d\n", ret); +} + +static void rb4xx_nand_read_buf(struct mtd_info *mtd, unsigned char *buf, + int len) +{ + struct nand_chip *chip = mtd->priv; + struct rb4xx_nand_info *info = chip->priv; + int ret; + + ret = rb4xx_cpld_read(info->spi_dev, buf, len); + if (ret) + pr_err("rb4xx_nand: read buf failed, error %d\n", ret); +} + +static int rb4xx_cpld_gpio_init(struct rb4xx_cpld *cpld, unsigned int base) +{ + int ret; + + cpld->chip.label = "rb4xx-cpld"; + cpld->chip.base = base; + cpld->chip.ngpio = CPLD_NUM_GPIOS; + cpld->chip.can_sleep = 1; + cpld->chip.dev = &cpld->spi->dev; + cpld->chip.get = rb4xx_cpld_gpio_get; + cpld->chip.set = rb4xx_cpld_gpio_set; + cpld->chip.direction_input = rb4xx_cpld_gpio_direction_input; + cpld->chip.direction_output = rb4xx_cpld_gpio_direction_output; + + ret = gpiochip_add(&cpld->chip); + if (ret) + dev_err(&cpld->spi->dev, "adding GPIO chip failed, error %d\n", + ret); + + return ret; +} + +static int rb4xx_cpld_probe(struct spi_device *spi) +{ + struct rb4xx_cpld *cpld; + struct rb4xx_cpld_platform_data *pdata; + int ret; + + pdata = dev_get_platdata(&spi->dev); + if (!pdata) + return -ENODATA; + + cpld = devm_kzalloc(&spi->dev, sizeof(*cpld), GFP_KERNEL); + if (!cpld) + return -ENOMEM; + + mutex_init(&cpld->lock); + cpld->spi = spi_dev_get(spi); + dev_set_drvdata(&spi->dev, cpld); + + ret = spi_setup(spi); + if (ret) { + dev_err(&spi->dev, "SPI setup failed, error %d\n", ret); + return ret; + } + + return rb4xx_cpld_gpio_init(cpld, pdata->gpio_base); +} + +static int rb4xx_cpld_remove(struct spi_device *spi) +{ + struct rb4xx_cpld *cpld; + + cpld = dev_get_drvdata(&spi->dev); + gpiochip_remove(&cpld->chip); + mutex_destroy(&cpld->lock); + + return 0; +} + +static struct spi_driver rb4xx_cpld_driver = { + .probe = rb4xx_cpld_probe, + .remove = rb4xx_cpld_remove, + .driver = { + .name = "rb4xx-cpld", + .owner = THIS_MODULE, + }, +}; + +static int rb4xx_nand_probe(struct platform_device *pdev) +{ + struct device *spi_dev; + struct rb4xx_nand_info *info; + struct rb4xx_cpld_platform_data *pdata; + int ret; + + /* + * NAND chip is behind the CPLD on SPI bus 0 CS 1. Allow this + * to silently fail the second time around. + */ + spi_register_driver(&rb4xx_cpld_driver); + + /* + * Getting a handle on the SPI device above will fail the first time, + * but should succeed whenever that driver gets probed. + */ + spi_dev = bus_find_device_by_name(&spi_bus_type, NULL, "spi0.1"); + if (!spi_dev) + return -EPROBE_DEFER; + + pdata = dev_get_platdata(spi_dev); + if (!pdata) + return -ENODATA; + + info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->gpio_ale = devm_gpiod_get(&pdev->dev, "NAND ALE", GPIOD_OUT_LOW); + if (IS_ERR(info->gpio_ale)) { + dev_err(&pdev->dev, "unable to request gpio NAND ALE: %ld\n", + PTR_ERR(info->gpio_ale)); + return -ENOENT; + } + + info->gpio_cle = devm_gpiod_get(&pdev->dev, "NAND CLE", GPIOD_OUT_LOW); + if (IS_ERR(info->gpio_cle)) { + dev_err(&pdev->dev, "unable to request gpio NAND CLE: %ld\n", + PTR_ERR(info->gpio_cle)); + return -ENOENT; + } + + info->gpio_nce = devm_gpiod_get(&pdev->dev, "NAND NCE", GPIOD_OUT_LOW); + if (IS_ERR(info->gpio_nce)) { + dev_err(&pdev->dev, "unable to request gpio NAND NCE: %ld\n", + PTR_ERR(info->gpio_nce)); + return -ENOENT; + } + + /* Platform GPIO, has no device to manage it. */ + info->gpio_rdy = gpiod_get(NULL, "NAND RDY", GPIOD_IN); + if (IS_ERR(info->gpio_rdy)) { + dev_err(&pdev->dev, "unable to request gpio RDY: %ld\n", + PTR_ERR(info->gpio_rdy)); + return -ENOENT; + } + + info->spi_dev = container_of(spi_dev, struct spi_device, dev); + + info->chip.priv = info; + info->mtd.priv = &info->chip; + info->mtd.owner = THIS_MODULE; + + info->chip.cmd_ctrl = rb4xx_nand_cmd_ctrl; + info->chip.dev_ready = rb4xx_nand_dev_ready; + info->chip.read_byte = rb4xx_nand_read_byte; + info->chip.write_buf = rb4xx_nand_write_buf; + info->chip.read_buf = rb4xx_nand_read_buf; + + info->chip.chip_delay = 25; + info->chip.ecc.mode = NAND_ECC_SOFT; + + platform_set_drvdata(pdev, info); + + ret = nand_scan_ident(&info->mtd, 1, NULL); + if (ret) { + ret = -ENXIO; + goto err_gpio; + } + + if (info->mtd.writesize == 512) + info->chip.ecc.layout = &rb4xx_nand_ecclayout; + + ret = nand_scan_tail(&info->mtd); + if (ret) { + ret = -ENXIO; + goto err_gpio; + } + + ret = mtd_device_register(&info->mtd, pdata->flash_data.parts, + pdata->flash_data.nr_parts); + if (ret) + goto err_release_nand; + + return 0; + +err_release_nand: + nand_release(&info->mtd); +err_gpio: + gpiod_put(info->gpio_rdy); + + return ret; +} + +static int rb4xx_nand_remove(struct platform_device *pdev) +{ + struct rb4xx_nand_info *info = platform_get_drvdata(pdev); + + nand_release(&info->mtd); + gpiod_put(info->gpio_rdy); + spi_unregister_driver(&rb4xx_cpld_driver); + + return 0; +} + +static struct platform_driver rb4xx_nand_driver = { + .probe = rb4xx_nand_probe, + .remove = rb4xx_nand_remove, + .driver = { + .name = "rb4xx-nand", + }, +}; + +module_platform_driver(rb4xx_nand_driver); + +MODULE_DESCRIPTION("NAND flash driver for RouterBoard 4xx series"); +MODULE_AUTHOR("Gabor Juhos "); +MODULE_AUTHOR("Imre Kaloz "); +MODULE_AUTHOR("Bert Vermeulen "); +MODULE_LICENSE("GPL v2"); -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/