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