/* * Copyright (C) 2006 Jonathan McDowell * * Derived from drivers/mtd/nand/toto.c (removed in v2.6.28) * Copyright (c) 2003 Texas Instruments * Copyright (c) 2002 Thomas Gleixner * * Converted to platform driver by Janusz Krzysztofik * Partially stolen from plat_nand.c * * 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. * * Overview: * This is a device driver for the NAND flash device found on the * Amstrad E3 (Delta). */ #include #include #include #include #include #include #include #include #include #include #include /* * MTD structure for E3 (Delta) */ struct ams_delta_nand { struct nand_chip nand_chip; struct gpio_desc *gpiod_rdy; struct gpio_desc *gpiod_nce; struct gpio_desc *gpiod_nre; struct gpio_desc *gpiod_nwp; struct gpio_desc *gpiod_nwe; struct gpio_desc *gpiod_ale; struct gpio_desc *gpiod_cle; void __iomem *io_base; bool data_in; }; /* * Define partitions for flash devices */ static const struct mtd_partition partition_info[] = { { .name = "Kernel", .offset = 0, .size = 3 * SZ_1M + SZ_512K }, { .name = "u-boot", .offset = 3 * SZ_1M + SZ_512K, .size = SZ_256K }, { .name = "u-boot params", .offset = 3 * SZ_1M + SZ_512K + SZ_256K, .size = SZ_256K }, { .name = "Amstrad LDR", .offset = 4 * SZ_1M, .size = SZ_256K }, { .name = "File system", .offset = 4 * SZ_1M + 1 * SZ_256K, .size = 27 * SZ_1M }, { .name = "PBL reserved", .offset = 32 * SZ_1M - 3 * SZ_256K, .size = 3 * SZ_256K }, }; static void ams_delta_io_write(struct ams_delta_nand *priv, u_char byte) { writew(byte, priv->nand_chip.legacy.IO_ADDR_W); gpiod_set_value(priv->gpiod_nwe, 0); ndelay(40); gpiod_set_value(priv->gpiod_nwe, 1); } static u_char ams_delta_io_read(struct ams_delta_nand *priv) { u_char res; gpiod_set_value(priv->gpiod_nre, 0); ndelay(40); res = readw(priv->nand_chip.legacy.IO_ADDR_R); gpiod_set_value(priv->gpiod_nre, 1); return res; } static void ams_delta_dir_input(struct ams_delta_nand *priv, bool in) { writew(in ? ~0 : 0, priv->io_base + OMAP_MPUIO_IO_CNTL); priv->data_in = in; } static void ams_delta_write_buf(struct nand_chip *this, const u_char *buf, int len) { struct ams_delta_nand *priv = nand_get_controller_data(this); int i; if (priv->data_in) ams_delta_dir_input(priv, false); for (i = 0; i < len; i++) ams_delta_io_write(priv, buf[i]); } static void ams_delta_read_buf(struct nand_chip *this, u_char *buf, int len) { struct ams_delta_nand *priv = nand_get_controller_data(this); int i; if (!priv->data_in) ams_delta_dir_input(priv, true); for (i = 0; i < len; i++) buf[i] = ams_delta_io_read(priv); } static u_char ams_delta_read_byte(struct nand_chip *this) { u_char res; ams_delta_read_buf(this, &res, 1); return res; } /* * Command control function * * ctrl: * NAND_NCE: bit 0 -> bit 2 * NAND_CLE: bit 1 -> bit 7 * NAND_ALE: bit 2 -> bit 6 */ static void ams_delta_hwcontrol(struct nand_chip *this, int cmd, unsigned int ctrl) { struct ams_delta_nand *priv = nand_get_controller_data(this); if (ctrl & NAND_CTRL_CHANGE) { gpiod_set_value(priv->gpiod_nce, !(ctrl & NAND_NCE)); gpiod_set_value(priv->gpiod_cle, !!(ctrl & NAND_CLE)); gpiod_set_value(priv->gpiod_ale, !!(ctrl & NAND_ALE)); } if (cmd != NAND_CMD_NONE) { u_char byte = cmd; ams_delta_write_buf(this, &byte, 1); } } static int ams_delta_nand_ready(struct nand_chip *this) { struct ams_delta_nand *priv = nand_get_controller_data(this); return gpiod_get_value(priv->gpiod_rdy); } /* * Main initialization routine */ static int ams_delta_init(struct platform_device *pdev) { struct ams_delta_nand *priv; struct nand_chip *this; struct mtd_info *mtd; struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); void __iomem *io_base; int err = 0; if (!res) return -ENXIO; /* Allocate memory for MTD device structure and private data */ priv = devm_kzalloc(&pdev->dev, sizeof(struct ams_delta_nand), GFP_KERNEL); if (!priv) { pr_warn("Unable to allocate E3 NAND MTD device structure.\n"); return -ENOMEM; } this = &priv->nand_chip; mtd = nand_to_mtd(this); mtd->dev.parent = &pdev->dev; /* * Don't try to request the memory region from here, * it should have been already requested from the * gpio-omap driver and requesting it again would fail. */ io_base = ioremap(res->start, resource_size(res)); if (io_base == NULL) { dev_err(&pdev->dev, "ioremap failed\n"); err = -EIO; goto out_free; } priv->io_base = io_base; nand_set_controller_data(this, priv); /* Set address of NAND IO lines */ this->legacy.IO_ADDR_R = io_base + OMAP_MPUIO_INPUT_LATCH; this->legacy.IO_ADDR_W = io_base + OMAP_MPUIO_OUTPUT; this->legacy.read_byte = ams_delta_read_byte; this->legacy.write_buf = ams_delta_write_buf; this->legacy.read_buf = ams_delta_read_buf; this->legacy.cmd_ctrl = ams_delta_hwcontrol; priv->gpiod_rdy = devm_gpiod_get_optional(&pdev->dev, "rdy", GPIOD_IN); if (IS_ERR(priv->gpiod_rdy)) { err = PTR_ERR(priv->gpiod_rdy); dev_warn(&pdev->dev, "RDY GPIO request failed (%d)\n", err); goto out_mtd; } if (priv->gpiod_rdy) this->legacy.dev_ready = ams_delta_nand_ready; /* 25 us command delay time */ this->legacy.chip_delay = 30; this->ecc.mode = NAND_ECC_SOFT; this->ecc.algo = NAND_ECC_HAMMING; platform_set_drvdata(pdev, priv); /* Set chip enabled, but */ priv->gpiod_nwp = devm_gpiod_get(&pdev->dev, "nwp", GPIOD_OUT_HIGH); if (IS_ERR(priv->gpiod_nwp)) { err = PTR_ERR(priv->gpiod_nwp); dev_err(&pdev->dev, "NWP GPIO request failed (%d)\n", err); goto out_mtd; } priv->gpiod_nce = devm_gpiod_get(&pdev->dev, "nce", GPIOD_OUT_HIGH); if (IS_ERR(priv->gpiod_nce)) { err = PTR_ERR(priv->gpiod_nce); dev_err(&pdev->dev, "NCE GPIO request failed (%d)\n", err); goto out_mtd; } priv->gpiod_nre = devm_gpiod_get(&pdev->dev, "nre", GPIOD_OUT_HIGH); if (IS_ERR(priv->gpiod_nre)) { err = PTR_ERR(priv->gpiod_nre); dev_err(&pdev->dev, "NRE GPIO request failed (%d)\n", err); goto out_mtd; } priv->gpiod_nwe = devm_gpiod_get(&pdev->dev, "nwe", GPIOD_OUT_HIGH); if (IS_ERR(priv->gpiod_nwe)) { err = PTR_ERR(priv->gpiod_nwe); dev_err(&pdev->dev, "NWE GPIO request failed (%d)\n", err); goto out_mtd; } priv->gpiod_ale = devm_gpiod_get(&pdev->dev, "ale", GPIOD_OUT_LOW); if (IS_ERR(priv->gpiod_ale)) { err = PTR_ERR(priv->gpiod_ale); dev_err(&pdev->dev, "ALE GPIO request failed (%d)\n", err); goto out_mtd; } priv->gpiod_cle = devm_gpiod_get(&pdev->dev, "cle", GPIOD_OUT_LOW); if (IS_ERR(priv->gpiod_cle)) { err = PTR_ERR(priv->gpiod_cle); dev_err(&pdev->dev, "CLE GPIO request failed (%d)\n", err); goto out_mtd; } /* Initialize data port direction to a known state */ ams_delta_dir_input(priv, true); /* Scan to find existence of the device */ err = nand_scan(this, 1); if (err) goto out_mtd; /* Register the partitions */ mtd_device_register(mtd, partition_info, ARRAY_SIZE(partition_info)); goto out; out_mtd: iounmap(io_base); out_free: out: return err; } /* * Clean up routine */ static int ams_delta_cleanup(struct platform_device *pdev) { struct ams_delta_nand *priv = platform_get_drvdata(pdev); struct mtd_info *mtd = nand_to_mtd(&priv->nand_chip); void __iomem *io_base = priv->io_base; /* Release resources, unregister device */ nand_release(mtd_to_nand(mtd)); iounmap(io_base); return 0; } static struct platform_driver ams_delta_nand_driver = { .probe = ams_delta_init, .remove = ams_delta_cleanup, .driver = { .name = "ams-delta-nand", }, }; module_platform_driver(ams_delta_nand_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Jonathan McDowell "); MODULE_DESCRIPTION("Glue layer for NAND flash on Amstrad E3 (Delta)");