target/linux/ar71xx/files/drivers/mtd/nand/rb4xx_nand.c

   1 /*
   2  *  NAND flash driver for the MikroTik RouterBoard 4xx series
   3  *
   4  *  Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
   5  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
   6  *
   7  *  This file was based on the driver for Linux 2.6.22 published by
   8  *  MikroTik for their RouterBoard 4xx series devices.
   9  *
  10  *  This program is free software; you can redistribute it and/or modify it
  11  *  under the terms of the GNU General Public License version 2 as published
  12  *  by the Free Software Foundation.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/mtd/nand.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/mtd/partitions.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/delay.h>
  23 #include <linux/io.h>
  24 #include <linux/gpio.h>
  25 #include <linux/slab.h>
  26
  27 #include <asm/mach-ath79/ath79.h>
  28 #include <asm/mach-ath79/rb4xx_cpld.h>
  29
  30 #define DRV_NAME        "rb4xx-nand"
  31 #define DRV_VERSION     "0.2.0"
  32 #define DRV_DESC        "NAND flash driver for RouterBoard 4xx series"
  33
  34 #define RB4XX_NAND_GPIO_READY   5
  35 #define RB4XX_NAND_GPIO_ALE     37
  36 #define RB4XX_NAND_GPIO_CLE     38
  37 #define RB4XX_NAND_GPIO_NCE     39
  38
  39 struct rb4xx_nand_info {
  40         struct nand_chip        chip;
  41         struct mtd_info         mtd;
  42 };
  43
  44 /*
  45  * We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
  46  * will not be able to find the kernel that we load.
  47  */
  48 static struct nand_ecclayout rb4xx_nand_ecclayout = {
  49         .eccbytes       = 6,
  50         .eccpos         = { 8, 9, 10, 13, 14, 15 },
  51         .oobavail       = 9,
  52         .oobfree        = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
  53 };
  54
  55 static struct mtd_partition rb4xx_nand_partitions[] = {
  56         {
  57                 .name   = "booter",
  58                 .offset = 0,
  59                 .size   = (256 * 1024),
  60                 .mask_flags = MTD_WRITEABLE,
  61         },
  62         {
  63                 .name   = "kernel",
  64                 .offset = (256 * 1024),
  65                 .size   = (4 * 1024 * 1024) - (256 * 1024),
  66         },
  67         {
  68                 .name   = "rootfs",
  69                 .offset = MTDPART_OFS_NXTBLK,
  70                 .size   = MTDPART_SIZ_FULL,
  71         },
  72 };
  73
  74 static int rb4xx_nand_dev_ready(struct mtd_info *mtd)
  75 {
  76         return gpio_get_value_cansleep(RB4XX_NAND_GPIO_READY);
  77 }
  78
  79 static void rb4xx_nand_write_cmd(unsigned char cmd)
  80 {
  81         unsigned char data = cmd;
  82         int err;
  83
  84         err = rb4xx_cpld_write(&data, 1);
  85         if (err)
  86                 pr_err("rb4xx_nand: write cmd failed, err=%d\n", err);
  87 }
  88
  89 static void rb4xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
  90                                 unsigned int ctrl)
  91 {
  92         if (ctrl & NAND_CTRL_CHANGE) {
  93                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_CLE,
  94                                         (ctrl & NAND_CLE) ? 1 : 0);
  95                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_ALE,
  96                                         (ctrl & NAND_ALE) ? 1 : 0);
  97                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_NCE,
  98                                         (ctrl & NAND_NCE) ? 0 : 1);
  99         }
 100
 101         if (cmd != NAND_CMD_NONE)
 102                 rb4xx_nand_write_cmd(cmd);
 103 }
 104
 105 static unsigned char rb4xx_nand_read_byte(struct mtd_info *mtd)
 106 {
 107         unsigned char data = 0;
 108         int err;
 109
 110         err = rb4xx_cpld_read(&data, 1);
 111         if (err) {
 112                 pr_err("rb4xx_nand: read data failed, err=%d\n", err);
 113                 data = 0xff;
 114         }
 115
 116         return data;
 117 }
 118
 119 static void rb4xx_nand_write_buf(struct mtd_info *mtd, const unsigned char *buf,
 120                                  int len)
 121 {
 122         int err;
 123
 124         err = rb4xx_cpld_write(buf, len);
 125         if (err)
 126                 pr_err("rb4xx_nand: write buf failed, err=%d\n", err);
 127 }
 128
 129 static void rb4xx_nand_read_buf(struct mtd_info *mtd, unsigned char *buf,
 130                                 int len)
 131 {
 132         int err;
 133
 134         err = rb4xx_cpld_read(buf, len);
 135         if (err)
 136                 pr_err("rb4xx_nand: read buf failed, err=%d\n", err);
 137 }
 138
 139 static int rb4xx_nand_probe(struct platform_device *pdev)
 140 {
 141         struct rb4xx_nand_info  *info;
 142         int ret;
 143
 144         printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
 145
 146         ret = gpio_request(RB4XX_NAND_GPIO_READY, "NAND RDY");
 147         if (ret) {
 148                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 149                         RB4XX_NAND_GPIO_READY);
 150                 goto err;
 151         }
 152
 153         ret = gpio_direction_input(RB4XX_NAND_GPIO_READY);
 154         if (ret) {
 155                 dev_err(&pdev->dev, "unable to set input mode on gpio %d\n",
 156                         RB4XX_NAND_GPIO_READY);
 157                 goto err_free_gpio_ready;
 158         }
 159
 160         ret = gpio_request(RB4XX_NAND_GPIO_ALE, "NAND ALE");
 161         if (ret) {
 162                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 163                         RB4XX_NAND_GPIO_ALE);
 164                 goto err_free_gpio_ready;
 165         }
 166
 167         ret = gpio_direction_output(RB4XX_NAND_GPIO_ALE, 0);
 168         if (ret) {
 169                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 170                         RB4XX_NAND_GPIO_ALE);
 171                 goto err_free_gpio_ale;
 172         }
 173
 174         ret = gpio_request(RB4XX_NAND_GPIO_CLE, "NAND CLE");
 175         if (ret) {
 176                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 177                         RB4XX_NAND_GPIO_CLE);
 178                 goto err_free_gpio_ale;
 179         }
 180
 181         ret = gpio_direction_output(RB4XX_NAND_GPIO_CLE, 0);
 182         if (ret) {
 183                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 184                         RB4XX_NAND_GPIO_CLE);
 185                 goto err_free_gpio_cle;
 186         }
 187
 188         ret = gpio_request(RB4XX_NAND_GPIO_NCE, "NAND NCE");
 189         if (ret) {
 190                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 191                         RB4XX_NAND_GPIO_NCE);
 192                 goto err_free_gpio_cle;
 193         }
 194
 195         ret = gpio_direction_output(RB4XX_NAND_GPIO_NCE, 1);
 196         if (ret) {
 197                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 198                         RB4XX_NAND_GPIO_ALE);
 199                 goto err_free_gpio_nce;
 200         }
 201
 202         info = kzalloc(sizeof(*info), GFP_KERNEL);
 203         if (!info) {
 204                 dev_err(&pdev->dev, "rb4xx-nand: no memory for private data\n");
 205                 ret = -ENOMEM;
 206                 goto err_free_gpio_nce;
 207         }
 208
 209         info->chip.priv = &info;
 210         info->mtd.priv  = &info->chip;
 211         info->mtd.owner = THIS_MODULE;
 212
 213         info->chip.cmd_ctrl     = rb4xx_nand_cmd_ctrl;
 214         info->chip.dev_ready    = rb4xx_nand_dev_ready;
 215         info->chip.read_byte    = rb4xx_nand_read_byte;
 216         info->chip.write_buf    = rb4xx_nand_write_buf;
 217         info->chip.read_buf     = rb4xx_nand_read_buf;
 218
 219         info->chip.chip_delay   = 25;
 220         info->chip.ecc.mode     = NAND_ECC_SOFT;
 221         info->chip.options = NAND_NO_SUBPAGE_WRITE;
 222
 223         platform_set_drvdata(pdev, info);
 224
 225         ret = nand_scan_ident(&info->mtd, 1, NULL);
 226         if (ret) {
 227                 ret = -ENXIO;
 228                 goto err_free_info;
 229         }
 230
 231         if (info->mtd.writesize == 512)
 232                 info->chip.ecc.layout = &rb4xx_nand_ecclayout;
 233
 234         ret = nand_scan_tail(&info->mtd);
 235         if (ret) {
 236                 return -ENXIO;
 237                 goto err_set_drvdata;
 238         }
 239
 240         mtd_device_register(&info->mtd, rb4xx_nand_partitions,
 241                                 ARRAY_SIZE(rb4xx_nand_partitions));
 242         if (ret)
 243                 goto err_release_nand;
 244
 245         return 0;
 246
 247 err_release_nand:
 248         nand_release(&info->mtd);
 249 err_set_drvdata:
 250         platform_set_drvdata(pdev, NULL);
 251 err_free_info:
 252         kfree(info);
 253 err_free_gpio_nce:
 254         gpio_free(RB4XX_NAND_GPIO_NCE);
 255 err_free_gpio_cle:
 256         gpio_free(RB4XX_NAND_GPIO_CLE);
 257 err_free_gpio_ale:
 258         gpio_free(RB4XX_NAND_GPIO_ALE);
 259 err_free_gpio_ready:
 260         gpio_free(RB4XX_NAND_GPIO_READY);
 261 err:
 262         return ret;
 263 }
 264
 265 static int rb4xx_nand_remove(struct platform_device *pdev)
 266 {
 267         struct rb4xx_nand_info *info = platform_get_drvdata(pdev);
 268
 269         nand_release(&info->mtd);
 270         platform_set_drvdata(pdev, NULL);
 271         kfree(info);
 272         gpio_free(RB4XX_NAND_GPIO_NCE);
 273         gpio_free(RB4XX_NAND_GPIO_CLE);
 274         gpio_free(RB4XX_NAND_GPIO_ALE);
 275         gpio_free(RB4XX_NAND_GPIO_READY);
 276
 277         return 0;
 278 }
 279
 280 static struct platform_driver rb4xx_nand_driver = {
 281         .probe  = rb4xx_nand_probe,
 282         .remove = rb4xx_nand_remove,
 283         .driver = {
 284                 .name   = DRV_NAME,
 285                 .owner  = THIS_MODULE,
 286         },
 287 };
 288
 289 static int __init rb4xx_nand_init(void)
 290 {
 291         return platform_driver_register(&rb4xx_nand_driver);
 292 }
 293
 294 static void __exit rb4xx_nand_exit(void)
 295 {
 296         platform_driver_unregister(&rb4xx_nand_driver);
 297 }
 298
 299 module_init(rb4xx_nand_init);
 300 module_exit(rb4xx_nand_exit);
 301
 302 MODULE_DESCRIPTION(DRV_DESC);
 303 MODULE_VERSION(DRV_VERSION);
 304 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 305 MODULE_AUTHOR("Imre Kaloz <kaloz@openwrt.org>");
 306 MODULE_LICENSE("GPL v2");