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) 2008-2010 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/init.h>
  16 #include <linux/mtd/nand.h>
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/mtd/partitions.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/delay.h>
  21 #include <linux/io.h>
  22 #include <linux/gpio.h>
  23 #include <linux/slab.h>
  24
  25 #include <asm/mach-ar71xx/ar71xx.h>
  26 #include <asm/mach-ar71xx/rb4xx_cpld.h>
  27
  28 #define DRV_NAME        "rb4xx-nand"
  29 #define DRV_VERSION     "0.2.0"
  30 #define DRV_DESC        "NAND flash driver for RouterBoard 4xx series"
  31
  32 #define RB4XX_NAND_GPIO_READY   5
  33 #define RB4XX_NAND_GPIO_ALE     37
  34 #define RB4XX_NAND_GPIO_CLE     38
  35 #define RB4XX_NAND_GPIO_NCE     39
  36
  37 struct rb4xx_nand_info {
  38         struct nand_chip        chip;
  39         struct mtd_info         mtd;
  40 };
  41
  42 /*
  43  * We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
  44  * will not be able to find the kernel that we load.
  45  */
  46 static struct nand_ecclayout rb4xx_nand_ecclayout = {
  47         .eccbytes       = 6,
  48         .eccpos         = { 8, 9, 10, 13, 14, 15 },
  49         .oobavail       = 9,
  50         .oobfree        = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
  51 };
  52
  53 static struct mtd_partition rb4xx_nand_partitions[] = {
  54         {
  55                 .name   = "booter",
  56                 .offset = 0,
  57                 .size   = (256 * 1024),
  58                 .mask_flags = MTD_WRITEABLE,
  59         },
  60         {
  61                 .name   = "kernel",
  62                 .offset = (256 * 1024),
  63                 .size   = (6 * 1024 * 1024) - (256 * 1024),
  64         },
  65         {
  66                 .name   = "rootfs",
  67                 .offset = MTDPART_OFS_NXTBLK,
  68                 .size   = MTDPART_SIZ_FULL,
  69         },
  70 };
  71
  72 static int rb4xx_nand_dev_ready(struct mtd_info *mtd)
  73 {
  74         return gpio_get_value(RB4XX_NAND_GPIO_READY);
  75 }
  76
  77 static void rb4xx_nand_write_cmd(unsigned char cmd)
  78 {
  79         unsigned char data = cmd;
  80         int err;
  81
  82         err = rb4xx_cpld_write(&data, 1);
  83         if (err)
  84                 pr_err("rb4xx_nand: write cmd failed, err=%d\n", err);
  85 }
  86
  87 static void rb4xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
  88                                 unsigned int ctrl)
  89 {
  90         if (ctrl & NAND_CTRL_CHANGE) {
  91                 gpio_set_value(RB4XX_NAND_GPIO_CLE, (ctrl & NAND_CLE) ? 1 : 0);
  92                 gpio_set_value(RB4XX_NAND_GPIO_ALE, (ctrl & NAND_ALE) ? 1 : 0);
  93                 gpio_set_value(RB4XX_NAND_GPIO_NCE, (ctrl & NAND_NCE) ? 0 : 1);
  94         }
  95
  96         if (cmd != NAND_CMD_NONE)
  97                 rb4xx_nand_write_cmd(cmd);
  98 }
  99
 100 static unsigned char rb4xx_nand_read_byte(struct mtd_info *mtd)
 101 {
 102         unsigned char data = 0;
 103         int err;
 104
 105         err = rb4xx_cpld_read(&data, NULL, 1);
 106         if (err) {
 107                 pr_err("rb4xx_nand: read data failed, err=%d\n", err);
 108                 data = 0xff;
 109         }
 110
 111         return data;
 112 }
 113
 114 static void rb4xx_nand_write_buf(struct mtd_info *mtd, const unsigned char *buf,
 115                                  int len)
 116 {
 117         int err;
 118
 119         err = rb4xx_cpld_write(buf, len);
 120         if (err)
 121                 pr_err("rb4xx_nand: write buf failed, err=%d\n", err);
 122 }
 123
 124 static void rb4xx_nand_read_buf(struct mtd_info *mtd, unsigned char *buf,
 125                                 int len)
 126 {
 127         int err;
 128
 129         err = rb4xx_cpld_read(buf, NULL, len);
 130         if (err)
 131                 pr_err("rb4xx_nand: read buf failed, err=%d\n", err);
 132 }
 133
 134 static int __init rb4xx_nand_probe(struct platform_device *pdev)
 135 {
 136         struct rb4xx_nand_info  *info;
 137         int ret;
 138
 139         printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
 140
 141         ret = gpio_request(RB4XX_NAND_GPIO_READY, "NAND RDY");
 142         if (ret) {
 143                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 144                         RB4XX_NAND_GPIO_READY);
 145                 goto err;
 146         }
 147
 148         ret = gpio_direction_input(RB4XX_NAND_GPIO_READY);
 149         if (ret) {
 150                 dev_err(&pdev->dev, "unable to set input mode on gpio %d\n",
 151                         RB4XX_NAND_GPIO_READY);
 152                 goto err_free_gpio_ready;
 153         }
 154
 155         ret = gpio_request(RB4XX_NAND_GPIO_ALE, "NAND ALE");
 156         if (ret) {
 157                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 158                         RB4XX_NAND_GPIO_ALE);
 159                 goto err_free_gpio_ready;
 160         }
 161
 162         ret = gpio_direction_output(RB4XX_NAND_GPIO_ALE, 0);
 163         if (ret) {
 164                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 165                         RB4XX_NAND_GPIO_ALE);
 166                 goto err_free_gpio_ale;
 167         }
 168
 169         ret = gpio_request(RB4XX_NAND_GPIO_CLE, "NAND CLE");
 170         if (ret) {
 171                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 172                         RB4XX_NAND_GPIO_CLE);
 173                 goto err_free_gpio_ale;
 174         }
 175
 176         ret = gpio_direction_output(RB4XX_NAND_GPIO_CLE, 0);
 177         if (ret) {
 178                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 179                         RB4XX_NAND_GPIO_CLE);
 180                 goto err_free_gpio_cle;
 181         }
 182
 183         ret = gpio_request(RB4XX_NAND_GPIO_NCE, "NAND NCE");
 184         if (ret) {
 185                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 186                         RB4XX_NAND_GPIO_NCE);
 187                 goto err_free_gpio_cle;
 188         }
 189
 190         ret = gpio_direction_output(RB4XX_NAND_GPIO_NCE, 1);
 191         if (ret) {
 192                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 193                         RB4XX_NAND_GPIO_ALE);
 194                 goto err_free_gpio_nce;
 195         }
 196
 197         info = kzalloc(sizeof(*info), GFP_KERNEL);
 198         if (!info) {
 199                 dev_err(&pdev->dev, "rb4xx-nand: no memory for private data\n");
 200                 ret = -ENOMEM;
 201                 goto err_free_gpio_nce;
 202         }
 203
 204         info->chip.priv = &info;
 205         info->mtd.priv  = &info->chip;
 206         info->mtd.owner = THIS_MODULE;
 207
 208         info->chip.cmd_ctrl     = rb4xx_nand_cmd_ctrl;
 209         info->chip.dev_ready    = rb4xx_nand_dev_ready;
 210         info->chip.read_byte    = rb4xx_nand_read_byte;
 211         info->chip.write_buf    = rb4xx_nand_write_buf;
 212         info->chip.read_buf     = rb4xx_nand_read_buf;
 213 //      info->chip.verify_buf   = rb4xx_nand_verify_buf;
 214
 215         info->chip.chip_delay   = 25;
 216         info->chip.ecc.mode     = NAND_ECC_SOFT;
 217         info->chip.options      |= NAND_NO_AUTOINCR;
 218
 219         platform_set_drvdata(pdev, info);
 220
 221         ret = nand_scan_ident(&info->mtd, 1);
 222         if (ret) {
 223                 ret = -ENXIO;
 224                 goto err_free_info;
 225         }
 226
 227         if (info->mtd.writesize == 512)
 228                 info->chip.ecc.layout = &rb4xx_nand_ecclayout;
 229
 230         ret = nand_scan_tail(&info->mtd);
 231         if (ret) {
 232                 return -ENXIO;
 233                 goto err_set_drvdata;
 234         }
 235
 236 #ifdef CONFIG_MTD_PARTITIONS
 237         ret = add_mtd_partitions(&info->mtd, rb4xx_nand_partitions,
 238                                 ARRAY_SIZE(rb4xx_nand_partitions));
 239 #else
 240         ret = add_mtd_device(&info->mtd);
 241 #endif
 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 __devexit 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 = __devexit_p(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");