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/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_cansleep(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_cansleep(RB4XX_NAND_GPIO_CLE,
  92                                         (ctrl & NAND_CLE) ? 1 : 0);
  93                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_ALE,
  94                                         (ctrl & NAND_ALE) ? 1 : 0);
  95                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_NCE,
  96                                         (ctrl & NAND_NCE) ? 0 : 1);
  97         }
  98
  99         if (cmd != NAND_CMD_NONE)
 100                 rb4xx_nand_write_cmd(cmd);
 101 }
 102
 103 static unsigned char rb4xx_nand_read_byte(struct mtd_info *mtd)
 104 {
 105         unsigned char data = 0;
 106         int err;
 107
 108         err = rb4xx_cpld_read(&data, NULL, 1);
 109         if (err) {
 110                 pr_err("rb4xx_nand: read data failed, err=%d\n", err);
 111                 data = 0xff;
 112         }
 113
 114         return data;
 115 }
 116
 117 static void rb4xx_nand_write_buf(struct mtd_info *mtd, const unsigned char *buf,
 118                                  int len)
 119 {
 120         int err;
 121
 122         err = rb4xx_cpld_write(buf, len);
 123         if (err)
 124                 pr_err("rb4xx_nand: write buf failed, err=%d\n", err);
 125 }
 126
 127 static void rb4xx_nand_read_buf(struct mtd_info *mtd, unsigned char *buf,
 128                                 int len)
 129 {
 130         int err;
 131
 132         err = rb4xx_cpld_read(buf, NULL, len);
 133         if (err)
 134                 pr_err("rb4xx_nand: read buf failed, err=%d\n", err);
 135 }
 136
 137 static int __init rb4xx_nand_probe(struct platform_device *pdev)
 138 {
 139         struct rb4xx_nand_info  *info;
 140         int ret;
 141
 142         printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
 143
 144         ret = gpio_request(RB4XX_NAND_GPIO_READY, "NAND RDY");
 145         if (ret) {
 146                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 147                         RB4XX_NAND_GPIO_READY);
 148                 goto err;
 149         }
 150
 151         ret = gpio_direction_input(RB4XX_NAND_GPIO_READY);
 152         if (ret) {
 153                 dev_err(&pdev->dev, "unable to set input mode on gpio %d\n",
 154                         RB4XX_NAND_GPIO_READY);
 155                 goto err_free_gpio_ready;
 156         }
 157
 158         ret = gpio_request(RB4XX_NAND_GPIO_ALE, "NAND ALE");
 159         if (ret) {
 160                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 161                         RB4XX_NAND_GPIO_ALE);
 162                 goto err_free_gpio_ready;
 163         }
 164
 165         ret = gpio_direction_output(RB4XX_NAND_GPIO_ALE, 0);
 166         if (ret) {
 167                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 168                         RB4XX_NAND_GPIO_ALE);
 169                 goto err_free_gpio_ale;
 170         }
 171
 172         ret = gpio_request(RB4XX_NAND_GPIO_CLE, "NAND CLE");
 173         if (ret) {
 174                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 175                         RB4XX_NAND_GPIO_CLE);
 176                 goto err_free_gpio_ale;
 177         }
 178
 179         ret = gpio_direction_output(RB4XX_NAND_GPIO_CLE, 0);
 180         if (ret) {
 181                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 182                         RB4XX_NAND_GPIO_CLE);
 183                 goto err_free_gpio_cle;
 184         }
 185
 186         ret = gpio_request(RB4XX_NAND_GPIO_NCE, "NAND NCE");
 187         if (ret) {
 188                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 189                         RB4XX_NAND_GPIO_NCE);
 190                 goto err_free_gpio_cle;
 191         }
 192
 193         ret = gpio_direction_output(RB4XX_NAND_GPIO_NCE, 1);
 194         if (ret) {
 195                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 196                         RB4XX_NAND_GPIO_ALE);
 197                 goto err_free_gpio_nce;
 198         }
 199
 200         info = kzalloc(sizeof(*info), GFP_KERNEL);
 201         if (!info) {
 202                 dev_err(&pdev->dev, "rb4xx-nand: no memory for private data\n");
 203                 ret = -ENOMEM;
 204                 goto err_free_gpio_nce;
 205         }
 206
 207         info->chip.priv = &info;
 208         info->mtd.priv  = &info->chip;
 209         info->mtd.owner = THIS_MODULE;
 210
 211         info->chip.cmd_ctrl     = rb4xx_nand_cmd_ctrl;
 212         info->chip.dev_ready    = rb4xx_nand_dev_ready;
 213         info->chip.read_byte    = rb4xx_nand_read_byte;
 214         info->chip.write_buf    = rb4xx_nand_write_buf;
 215         info->chip.read_buf     = rb4xx_nand_read_buf;
 216 #if 0
 217         info->chip.verify_buf   = rb4xx_nand_verify_buf;
 218 #endif
 219
 220         info->chip.chip_delay   = 25;
 221         info->chip.ecc.mode     = NAND_ECC_SOFT;
 222         info->chip.options      |= NAND_NO_AUTOINCR;
 223
 224         platform_set_drvdata(pdev, info);
 225
 226         ret = nand_scan_ident(&info->mtd, 1, NULL);
 227         if (ret) {
 228                 ret = -ENXIO;
 229                 goto err_free_info;
 230         }
 231
 232         if (info->mtd.writesize == 512)
 233                 info->chip.ecc.layout = &rb4xx_nand_ecclayout;
 234
 235         ret = nand_scan_tail(&info->mtd);
 236         if (ret) {
 237                 return -ENXIO;
 238                 goto err_set_drvdata;
 239         }
 240
 241 #ifdef CONFIG_MTD_PARTITIONS
 242         ret = add_mtd_partitions(&info->mtd, rb4xx_nand_partitions,
 243                                 ARRAY_SIZE(rb4xx_nand_partitions));
 244 #else
 245         ret = add_mtd_device(&info->mtd);
 246 #endif
 247         if (ret)
 248                 goto err_release_nand;
 249
 250         return 0;
 251
 252 err_release_nand:
 253         nand_release(&info->mtd);
 254 err_set_drvdata:
 255         platform_set_drvdata(pdev, NULL);
 256 err_free_info:
 257         kfree(info);
 258 err_free_gpio_nce:
 259         gpio_free(RB4XX_NAND_GPIO_NCE);
 260 err_free_gpio_cle:
 261         gpio_free(RB4XX_NAND_GPIO_CLE);
 262 err_free_gpio_ale:
 263         gpio_free(RB4XX_NAND_GPIO_ALE);
 264 err_free_gpio_ready:
 265         gpio_free(RB4XX_NAND_GPIO_READY);
 266 err:
 267         return ret;
 268 }
 269
 270 static int __devexit rb4xx_nand_remove(struct platform_device *pdev)
 271 {
 272         struct rb4xx_nand_info *info = platform_get_drvdata(pdev);
 273
 274         nand_release(&info->mtd);
 275         platform_set_drvdata(pdev, NULL);
 276         kfree(info);
 277         gpio_free(RB4XX_NAND_GPIO_NCE);
 278         gpio_free(RB4XX_NAND_GPIO_CLE);
 279         gpio_free(RB4XX_NAND_GPIO_ALE);
 280         gpio_free(RB4XX_NAND_GPIO_READY);
 281
 282         return 0;
 283 }
 284
 285 static struct platform_driver rb4xx_nand_driver = {
 286         .probe  = rb4xx_nand_probe,
 287         .remove = __devexit_p(rb4xx_nand_remove),
 288         .driver = {
 289                 .name   = DRV_NAME,
 290                 .owner  = THIS_MODULE,
 291         },
 292 };
 293
 294 static int __init rb4xx_nand_init(void)
 295 {
 296         return platform_driver_register(&rb4xx_nand_driver);
 297 }
 298
 299 static void __exit rb4xx_nand_exit(void)
 300 {
 301         platform_driver_unregister(&rb4xx_nand_driver);
 302 }
 303
 304 module_init(rb4xx_nand_init);
 305 module_exit(rb4xx_nand_exit);
 306
 307 MODULE_DESCRIPTION(DRV_DESC);
 308 MODULE_VERSION(DRV_VERSION);
 309 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 310 MODULE_AUTHOR("Imre Kaloz <kaloz@openwrt.org>");
 311 MODULE_LICENSE("GPL v2");