drivers/mtd/nand/cmx270_nand.c

   1 /*
   2  *  linux/drivers/mtd/nand/cmx270-nand.c
   3  *
   4  *  Copyright (C) 2006 Compulab, Ltd.
   5  *  Mike Rapoport <mike@compulab.co.il>
   6  *
   7  *  Derived from drivers/mtd/nand/h1910.c
   8  *       Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
   9  *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
  10  *
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License version 2 as
  14  * published by the Free Software Foundation.
  15  *
  16  *  Overview:
  17  *   This is a device driver for the NAND flash device found on the
  18  *   CM-X270 board.
  19  */
  20
  21 #include <linux/mtd/nand.h>
  22 #include <linux/mtd/partitions.h>
  23 #include <linux/gpio.h>
  24
  25 #include <asm/io.h>
  26 #include <asm/irq.h>
  27 #include <asm/mach-types.h>
  28
  29 #include <mach/pxa2xx-regs.h>
  30
  31 #define GPIO_NAND_CS    (11)
  32 #define GPIO_NAND_RB    (89)
  33
  34 /* MTD structure for CM-X270 board */
  35 static struct mtd_info *cmx270_nand_mtd;
  36
  37 /* remaped IO address of the device */
  38 static void __iomem *cmx270_nand_io;
  39
  40 /*
  41  * Define static partitions for flash device
  42  */
  43 static struct mtd_partition partition_info[] = {
  44         [0] = {
  45                 .name   = "cmx270-0",
  46                 .offset = 0,
  47                 .size   = MTDPART_SIZ_FULL
  48         }
  49 };
  50 #define NUM_PARTITIONS (ARRAY_SIZE(partition_info))
  51
  52 const char *part_probes[] = { "cmdlinepart", NULL };
  53
  54 static u_char cmx270_read_byte(struct mtd_info *mtd)
  55 {
  56         struct nand_chip *this = mtd->priv;
  57
  58         return (readl(this->IO_ADDR_R) >> 16);
  59 }
  60
  61 static void cmx270_write_buf(struct mtd_info *mtd, const u_char *buf, int len)
  62 {
  63         int i;
  64         struct nand_chip *this = mtd->priv;
  65
  66         for (i=0; i<len; i++)
  67                 writel((*buf++ << 16), this->IO_ADDR_W);
  68 }
  69
  70 static void cmx270_read_buf(struct mtd_info *mtd, u_char *buf, int len)
  71 {
  72         int i;
  73         struct nand_chip *this = mtd->priv;
  74
  75         for (i=0; i<len; i++)
  76                 *buf++ = readl(this->IO_ADDR_R) >> 16;
  77 }
  78
  79 static int cmx270_verify_buf(struct mtd_info *mtd, const u_char *buf, int len)
  80 {
  81         int i;
  82         struct nand_chip *this = mtd->priv;
  83
  84         for (i=0; i<len; i++)
  85                 if (buf[i] != (u_char)(readl(this->IO_ADDR_R) >> 16))
  86                         return -EFAULT;
  87
  88         return 0;
  89 }
  90
  91 static inline void nand_cs_on(void)
  92 {
  93         gpio_set_value(GPIO_NAND_CS, 0);
  94 }
  95
  96 static void nand_cs_off(void)
  97 {
  98         dsb();
  99
 100         gpio_set_value(GPIO_NAND_CS, 1);
 101 }
 102
 103 /*
 104  *      hardware specific access to control-lines
 105  */
 106 static void cmx270_hwcontrol(struct mtd_info *mtd, int dat,
 107                              unsigned int ctrl)
 108 {
 109         struct nand_chip* this = mtd->priv;
 110         unsigned int nandaddr = (unsigned int)this->IO_ADDR_W;
 111
 112         dsb();
 113
 114         if (ctrl & NAND_CTRL_CHANGE) {
 115                 if ( ctrl & NAND_ALE )
 116                         nandaddr |=  (1 << 3);
 117                 else
 118                         nandaddr &= ~(1 << 3);
 119                 if ( ctrl & NAND_CLE )
 120                         nandaddr |=  (1 << 2);
 121                 else
 122                         nandaddr &= ~(1 << 2);
 123                 if ( ctrl & NAND_NCE )
 124                         nand_cs_on();
 125                 else
 126                         nand_cs_off();
 127         }
 128
 129         dsb();
 130         this->IO_ADDR_W = (void __iomem*)nandaddr;
 131         if (dat != NAND_CMD_NONE)
 132                 writel((dat << 16), this->IO_ADDR_W);
 133
 134         dsb();
 135 }
 136
 137 /*
 138  *      read device ready pin
 139  */
 140 static int cmx270_device_ready(struct mtd_info *mtd)
 141 {
 142         dsb();
 143
 144         return (gpio_get_value(GPIO_NAND_RB));
 145 }
 146
 147 /*
 148  * Main initialization routine
 149  */
 150 static int cmx270_init(void)
 151 {
 152         struct nand_chip *this;
 153         const char *part_type;
 154         struct mtd_partition *mtd_parts;
 155         int mtd_parts_nb = 0;
 156         int ret;
 157
 158         if (!(machine_is_armcore() && cpu_is_pxa27x()))
 159                 return -ENODEV;
 160
 161         ret = gpio_request(GPIO_NAND_CS, "NAND CS");
 162         if (ret) {
 163                 pr_warning("CM-X270: failed to request NAND CS gpio\n");
 164                 return ret;
 165         }
 166
 167         gpio_direction_output(GPIO_NAND_CS, 1);
 168
 169         ret = gpio_request(GPIO_NAND_RB, "NAND R/B");
 170         if (ret) {
 171                 pr_warning("CM-X270: failed to request NAND R/B gpio\n");
 172                 goto err_gpio_request;
 173         }
 174
 175         gpio_direction_input(GPIO_NAND_RB);
 176
 177         /* Allocate memory for MTD device structure and private data */
 178         cmx270_nand_mtd = kzalloc(sizeof(struct mtd_info) +
 179                                   sizeof(struct nand_chip),
 180                                   GFP_KERNEL);
 181         if (!cmx270_nand_mtd) {
 182                 pr_debug("Unable to allocate CM-X270 NAND MTD device structure.\n");
 183                 ret = -ENOMEM;
 184                 goto err_kzalloc;
 185         }
 186
 187         cmx270_nand_io = ioremap(PXA_CS1_PHYS, 12);
 188         if (!cmx270_nand_io) {
 189                 pr_debug("Unable to ioremap NAND device\n");
 190                 ret = -EINVAL;
 191                 goto err_ioremap;
 192         }
 193
 194         /* Get pointer to private data */
 195         this = (struct nand_chip *)(&cmx270_nand_mtd[1]);
 196
 197         /* Link the private data with the MTD structure */
 198         cmx270_nand_mtd->owner = THIS_MODULE;
 199         cmx270_nand_mtd->priv = this;
 200
 201         /* insert callbacks */
 202         this->IO_ADDR_R = cmx270_nand_io;
 203         this->IO_ADDR_W = cmx270_nand_io;
 204         this->cmd_ctrl = cmx270_hwcontrol;
 205         this->dev_ready = cmx270_device_ready;
 206
 207         /* 15 us command delay time */
 208         this->chip_delay = 20;
 209         this->ecc.mode = NAND_ECC_SOFT;
 210
 211         /* read/write functions */
 212         this->read_byte = cmx270_read_byte;
 213         this->read_buf = cmx270_read_buf;
 214         this->write_buf = cmx270_write_buf;
 215         this->verify_buf = cmx270_verify_buf;
 216
 217         /* Scan to find existence of the device */
 218         if (nand_scan (cmx270_nand_mtd, 1)) {
 219                 pr_notice("No NAND device\n");
 220                 ret = -ENXIO;
 221                 goto err_scan;
 222         }
 223
 224 #ifdef CONFIG_MTD_CMDLINE_PARTS
 225         mtd_parts_nb = parse_mtd_partitions(cmx270_nand_mtd, part_probes,
 226                                             &mtd_parts, 0);
 227         if (mtd_parts_nb > 0)
 228                 part_type = "command line";
 229         else
 230                 mtd_parts_nb = 0;
 231 #endif
 232         if (!mtd_parts_nb) {
 233                 mtd_parts = partition_info;
 234                 mtd_parts_nb = NUM_PARTITIONS;
 235                 part_type = "static";
 236         }
 237
 238         /* Register the partitions */
 239         pr_notice("Using %s partition definition\n", part_type);
 240         ret = add_mtd_partitions(cmx270_nand_mtd, mtd_parts, mtd_parts_nb);
 241         if (ret)
 242                 goto err_scan;
 243
 244         /* Return happy */
 245         return 0;
 246
 247 err_scan:
 248         iounmap(cmx270_nand_io);
 249 err_ioremap:
 250         kfree(cmx270_nand_mtd);
 251 err_kzalloc:
 252         gpio_free(GPIO_NAND_RB);
 253 err_gpio_request:
 254         gpio_free(GPIO_NAND_CS);
 255
 256         return ret;
 257
 258 }
 259 module_init(cmx270_init);
 260
 261 /*
 262  * Clean up routine
 263  */
 264 static void cmx270_cleanup(void)
 265 {
 266         /* Release resources, unregister device */
 267         nand_release(cmx270_nand_mtd);
 268
 269         gpio_free(GPIO_NAND_RB);
 270         gpio_free(GPIO_NAND_CS);
 271
 272         iounmap(cmx270_nand_io);
 273
 274         /* Free the MTD device structure */
 275         kfree (cmx270_nand_mtd);
 276 }
 277 module_exit(cmx270_cleanup);
 278
 279 MODULE_LICENSE("GPL");
 280 MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>");
 281 MODULE_DESCRIPTION("NAND flash driver for Compulab CM-X270 Module");