drivers/mtd/nand/fsl_upm.c

   1 /*
   2  * Freescale UPM NAND driver.
   3  *
   4  * Copyright © 2007-2008  MontaVista Software, Inc.
   5  *
   6  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  */
  13
  14 #include <linux/kernel.h>
  15 #include <linux/module.h>
  16 #include <linux/mtd/nand.h>
  17 #include <linux/mtd/nand_ecc.h>
  18 #include <linux/mtd/partitions.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/of_platform.h>
  21 #include <linux/of_gpio.h>
  22 #include <linux/io.h>
  23 #include <asm/fsl_lbc.h>
  24
  25 struct fsl_upm_nand {
  26         struct device *dev;
  27         struct mtd_info mtd;
  28         struct nand_chip chip;
  29         int last_ctrl;
  30 #ifdef CONFIG_MTD_PARTITIONS
  31         struct mtd_partition *parts;
  32 #endif
  33
  34         struct fsl_upm upm;
  35         uint8_t upm_addr_offset;
  36         uint8_t upm_cmd_offset;
  37         void __iomem *io_base;
  38         int rnb_gpio;
  39         const uint32_t *wait_pattern;
  40         const uint32_t *wait_write;
  41         int chip_delay;
  42 };
  43
  44 #define to_fsl_upm_nand(mtd) container_of(mtd, struct fsl_upm_nand, mtd)
  45
  46 static int fun_chip_ready(struct mtd_info *mtd)
  47 {
  48         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  49
  50         if (gpio_get_value(fun->rnb_gpio))
  51                 return 1;
  52
  53         dev_vdbg(fun->dev, "busy\n");
  54         return 0;
  55 }
  56
  57 static void fun_wait_rnb(struct fsl_upm_nand *fun)
  58 {
  59         int cnt = 1000000;
  60
  61         if (fun->rnb_gpio >= 0) {
  62                 while (--cnt && !fun_chip_ready(&fun->mtd))
  63                         cpu_relax();
  64         }
  65
  66         if (!cnt)
  67                 dev_err(fun->dev, "tired waiting for RNB\n");
  68 }
  69
  70 static void fun_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  71 {
  72         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  73
  74         if (!(ctrl & fun->last_ctrl)) {
  75                 fsl_upm_end_pattern(&fun->upm);
  76
  77                 if (cmd == NAND_CMD_NONE)
  78                         return;
  79
  80                 fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
  81         }
  82
  83         if (ctrl & NAND_CTRL_CHANGE) {
  84                 if (ctrl & NAND_ALE)
  85                         fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
  86                 else if (ctrl & NAND_CLE)
  87                         fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
  88         }
  89
  90         fsl_upm_run_pattern(&fun->upm, fun->io_base, cmd);
  91
  92         if (fun->wait_pattern)
  93                 fun_wait_rnb(fun);
  94 }
  95
  96 static uint8_t fun_read_byte(struct mtd_info *mtd)
  97 {
  98         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  99
 100         return in_8(fun->chip.IO_ADDR_R);
 101 }
 102
 103 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 104 {
 105         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 106         int i;
 107
 108         for (i = 0; i < len; i++)
 109                 buf[i] = in_8(fun->chip.IO_ADDR_R);
 110 }
 111
 112 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 113 {
 114         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 115         int i;
 116
 117         for (i = 0; i < len; i++) {
 118                 out_8(fun->chip.IO_ADDR_W, buf[i]);
 119                 if (fun->wait_write)
 120                         fun_wait_rnb(fun);
 121         }
 122 }
 123
 124 static int __devinit fun_chip_init(struct fsl_upm_nand *fun)
 125 {
 126         int ret;
 127 #ifdef CONFIG_MTD_PARTITIONS
 128         static const char *part_types[] = { "cmdlinepart", NULL, };
 129 #endif
 130
 131         fun->chip.IO_ADDR_R = fun->io_base;
 132         fun->chip.IO_ADDR_W = fun->io_base;
 133         fun->chip.cmd_ctrl = fun_cmd_ctrl;
 134         fun->chip.chip_delay = fun->chip_delay;
 135         fun->chip.read_byte = fun_read_byte;
 136         fun->chip.read_buf = fun_read_buf;
 137         fun->chip.write_buf = fun_write_buf;
 138         fun->chip.ecc.mode = NAND_ECC_SOFT;
 139
 140         if (fun->rnb_gpio >= 0)
 141                 fun->chip.dev_ready = fun_chip_ready;
 142
 143         fun->mtd.priv = &fun->chip;
 144         fun->mtd.owner = THIS_MODULE;
 145
 146         ret = nand_scan(&fun->mtd, 1);
 147         if (ret)
 148                 return ret;
 149
 150         fun->mtd.name = fun->dev->bus_id;
 151
 152 #ifdef CONFIG_MTD_PARTITIONS
 153         ret = parse_mtd_partitions(&fun->mtd, part_types, &fun->parts, 0);
 154         if (ret > 0)
 155                 return add_mtd_partitions(&fun->mtd, fun->parts, ret);
 156 #endif
 157         return add_mtd_device(&fun->mtd);
 158 }
 159
 160 static int __devinit fun_probe(struct of_device *ofdev,
 161                                const struct of_device_id *ofid)
 162 {
 163         struct fsl_upm_nand *fun;
 164         struct resource io_res;
 165         const uint32_t *prop;
 166         int ret;
 167         int size;
 168
 169         fun = kzalloc(sizeof(*fun), GFP_KERNEL);
 170         if (!fun)
 171                 return -ENOMEM;
 172
 173         ret = of_address_to_resource(ofdev->node, 0, &io_res);
 174         if (ret) {
 175                 dev_err(&ofdev->dev, "can't get IO base\n");
 176                 goto err1;
 177         }
 178
 179         ret = fsl_upm_find(io_res.start, &fun->upm);
 180         if (ret) {
 181                 dev_err(&ofdev->dev, "can't find UPM\n");
 182                 goto err1;
 183         }
 184
 185         prop = of_get_property(ofdev->node, "fsl,upm-addr-offset", &size);
 186         if (!prop || size != sizeof(uint32_t)) {
 187                 dev_err(&ofdev->dev, "can't get UPM address offset\n");
 188                 ret = -EINVAL;
 189                 goto err2;
 190         }
 191         fun->upm_addr_offset = *prop;
 192
 193         prop = of_get_property(ofdev->node, "fsl,upm-cmd-offset", &size);
 194         if (!prop || size != sizeof(uint32_t)) {
 195                 dev_err(&ofdev->dev, "can't get UPM command offset\n");
 196                 ret = -EINVAL;
 197                 goto err2;
 198         }
 199         fun->upm_cmd_offset = *prop;
 200
 201         fun->rnb_gpio = of_get_gpio(ofdev->node, 0);
 202         if (fun->rnb_gpio >= 0) {
 203                 ret = gpio_request(fun->rnb_gpio, ofdev->dev.bus_id);
 204                 if (ret) {
 205                         dev_err(&ofdev->dev, "can't request RNB gpio\n");
 206                         goto err2;
 207                 }
 208                 gpio_direction_input(fun->rnb_gpio);
 209         } else if (fun->rnb_gpio == -EINVAL) {
 210                 dev_err(&ofdev->dev, "specified RNB gpio is invalid\n");
 211                 goto err2;
 212         }
 213
 214         fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
 215                                           io_res.end - io_res.start + 1);
 216         if (!fun->io_base) {
 217                 ret = -ENOMEM;
 218                 goto err2;
 219         }
 220
 221         fun->dev = &ofdev->dev;
 222         fun->last_ctrl = NAND_CLE;
 223         fun->wait_pattern = of_get_property(ofdev->node, "fsl,wait-pattern",
 224                                             NULL);
 225         fun->wait_write = of_get_property(ofdev->node, "fsl,wait-write", NULL);
 226
 227         prop = of_get_property(ofdev->node, "chip-delay", NULL);
 228         if (prop)
 229                 fun->chip_delay = *prop;
 230         else
 231                 fun->chip_delay = 50;
 232
 233         ret = fun_chip_init(fun);
 234         if (ret)
 235                 goto err2;
 236
 237         dev_set_drvdata(&ofdev->dev, fun);
 238
 239         return 0;
 240 err2:
 241         if (fun->rnb_gpio >= 0)
 242                 gpio_free(fun->rnb_gpio);
 243 err1:
 244         kfree(fun);
 245
 246         return ret;
 247 }
 248
 249 static int __devexit fun_remove(struct of_device *ofdev)
 250 {
 251         struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
 252
 253         nand_release(&fun->mtd);
 254
 255         if (fun->rnb_gpio >= 0)
 256                 gpio_free(fun->rnb_gpio);
 257
 258         kfree(fun);
 259
 260         return 0;
 261 }
 262
 263 static struct of_device_id of_fun_match[] = {
 264         { .compatible = "fsl,upm-nand" },
 265         {},
 266 };
 267 MODULE_DEVICE_TABLE(of, of_fun_match);
 268
 269 static struct of_platform_driver of_fun_driver = {
 270         .name           = "fsl,upm-nand",
 271         .match_table    = of_fun_match,
 272         .probe          = fun_probe,
 273         .remove         = __devexit_p(fun_remove),
 274 };
 275
 276 static int __init fun_module_init(void)
 277 {
 278         return of_register_platform_driver(&of_fun_driver);
 279 }
 280 module_init(fun_module_init);
 281
 282 static void __exit fun_module_exit(void)
 283 {
 284         of_unregister_platform_driver(&of_fun_driver);
 285 }
 286 module_exit(fun_module_exit);
 287
 288 MODULE_LICENSE("GPL");
 289 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
 290 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
 291                    "LocalBus User-Programmable Machine");