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/delay.h>
  17 #include <linux/mtd/nand.h>
  18 #include <linux/mtd/nand_ecc.h>
  19 #include <linux/mtd/partitions.h>
  20 #include <linux/mtd/mtd.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/of_gpio.h>
  23 #include <linux/io.h>
  24 #include <asm/fsl_lbc.h>
  25
  26 struct fsl_upm_nand {
  27         struct device *dev;
  28         struct mtd_info mtd;
  29         struct nand_chip chip;
  30         int last_ctrl;
  31 #ifdef CONFIG_MTD_PARTITIONS
  32         struct mtd_partition *parts;
  33 #endif
  34
  35         struct fsl_upm upm;
  36         uint8_t upm_addr_offset;
  37         uint8_t upm_cmd_offset;
  38         void __iomem *io_base;
  39         int rnb_gpio;
  40         int chip_delay;
  41 };
  42
  43 #define to_fsl_upm_nand(mtd) container_of(mtd, struct fsl_upm_nand, mtd)
  44
  45 static int fun_chip_ready(struct mtd_info *mtd)
  46 {
  47         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  48
  49         if (gpio_get_value(fun->rnb_gpio))
  50                 return 1;
  51
  52         dev_vdbg(fun->dev, "busy\n");
  53         return 0;
  54 }
  55
  56 static void fun_wait_rnb(struct fsl_upm_nand *fun)
  57 {
  58         int cnt = 1000000;
  59
  60         if (fun->rnb_gpio >= 0) {
  61                 while (--cnt && !fun_chip_ready(&fun->mtd))
  62                         cpu_relax();
  63                 if (!cnt)
  64                         dev_err(fun->dev, "tired waiting for RNB\n");
  65         } else {
  66                 ndelay(100);
  67         }
  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         fun_wait_rnb(fun);
  93 }
  94
  95 static uint8_t fun_read_byte(struct mtd_info *mtd)
  96 {
  97         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  98
  99         return in_8(fun->chip.IO_ADDR_R);
 100 }
 101
 102 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 103 {
 104         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 105         int i;
 106
 107         for (i = 0; i < len; i++)
 108                 buf[i] = in_8(fun->chip.IO_ADDR_R);
 109 }
 110
 111 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 112 {
 113         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 114         int i;
 115
 116         for (i = 0; i < len; i++) {
 117                 out_8(fun->chip.IO_ADDR_W, buf[i]);
 118                 fun_wait_rnb(fun);
 119         }
 120 }
 121
 122 static int __devinit fun_chip_init(struct fsl_upm_nand *fun,
 123                                    const struct device_node *upm_np,
 124                                    const struct resource *io_res)
 125 {
 126         int ret;
 127         struct device_node *flash_np;
 128 #ifdef CONFIG_MTD_PARTITIONS
 129         static const char *part_types[] = { "cmdlinepart", NULL, };
 130 #endif
 131
 132         fun->chip.IO_ADDR_R = fun->io_base;
 133         fun->chip.IO_ADDR_W = fun->io_base;
 134         fun->chip.cmd_ctrl = fun_cmd_ctrl;
 135         fun->chip.chip_delay = fun->chip_delay;
 136         fun->chip.read_byte = fun_read_byte;
 137         fun->chip.read_buf = fun_read_buf;
 138         fun->chip.write_buf = fun_write_buf;
 139         fun->chip.ecc.mode = NAND_ECC_SOFT;
 140
 141         if (fun->rnb_gpio >= 0)
 142                 fun->chip.dev_ready = fun_chip_ready;
 143
 144         fun->mtd.priv = &fun->chip;
 145         fun->mtd.owner = THIS_MODULE;
 146
 147         flash_np = of_get_next_child(upm_np, NULL);
 148         if (!flash_np)
 149                 return -ENODEV;
 150
 151         fun->mtd.name = kasprintf(GFP_KERNEL, "%x.%s", io_res->start,
 152                                   flash_np->name);
 153         if (!fun->mtd.name) {
 154                 ret = -ENOMEM;
 155                 goto err;
 156         }
 157
 158         ret = nand_scan(&fun->mtd, 1);
 159         if (ret)
 160                 goto err;
 161
 162 #ifdef CONFIG_MTD_PARTITIONS
 163         ret = parse_mtd_partitions(&fun->mtd, part_types, &fun->parts, 0);
 164
 165 #ifdef CONFIG_MTD_OF_PARTS
 166         if (ret == 0)
 167                 ret = of_mtd_parse_partitions(fun->dev, &fun->mtd,
 168                                               flash_np, &fun->parts);
 169 #endif
 170         if (ret > 0)
 171                 ret = add_mtd_partitions(&fun->mtd, fun->parts, ret);
 172         else
 173 #endif
 174                 ret = add_mtd_device(&fun->mtd);
 175 err:
 176         of_node_put(flash_np);
 177         return ret;
 178 }
 179
 180 static int __devinit fun_probe(struct of_device *ofdev,
 181                                const struct of_device_id *ofid)
 182 {
 183         struct fsl_upm_nand *fun;
 184         struct resource io_res;
 185         const uint32_t *prop;
 186         int ret;
 187         int size;
 188
 189         fun = kzalloc(sizeof(*fun), GFP_KERNEL);
 190         if (!fun)
 191                 return -ENOMEM;
 192
 193         ret = of_address_to_resource(ofdev->node, 0, &io_res);
 194         if (ret) {
 195                 dev_err(&ofdev->dev, "can't get IO base\n");
 196                 goto err1;
 197         }
 198
 199         ret = fsl_upm_find(io_res.start, &fun->upm);
 200         if (ret) {
 201                 dev_err(&ofdev->dev, "can't find UPM\n");
 202                 goto err1;
 203         }
 204
 205         prop = of_get_property(ofdev->node, "fsl,upm-addr-offset", &size);
 206         if (!prop || size != sizeof(uint32_t)) {
 207                 dev_err(&ofdev->dev, "can't get UPM address offset\n");
 208                 ret = -EINVAL;
 209                 goto err2;
 210         }
 211         fun->upm_addr_offset = *prop;
 212
 213         prop = of_get_property(ofdev->node, "fsl,upm-cmd-offset", &size);
 214         if (!prop || size != sizeof(uint32_t)) {
 215                 dev_err(&ofdev->dev, "can't get UPM command offset\n");
 216                 ret = -EINVAL;
 217                 goto err2;
 218         }
 219         fun->upm_cmd_offset = *prop;
 220
 221         fun->rnb_gpio = of_get_gpio(ofdev->node, 0);
 222         if (fun->rnb_gpio >= 0) {
 223                 ret = gpio_request(fun->rnb_gpio, ofdev->dev.bus_id);
 224                 if (ret) {
 225                         dev_err(&ofdev->dev, "can't request RNB gpio\n");
 226                         goto err2;
 227                 }
 228                 gpio_direction_input(fun->rnb_gpio);
 229         } else if (fun->rnb_gpio == -EINVAL) {
 230                 dev_err(&ofdev->dev, "specified RNB gpio is invalid\n");
 231                 goto err2;
 232         }
 233
 234         prop = of_get_property(ofdev->node, "chip-delay", NULL);
 235         if (prop)
 236                 fun->chip_delay = *prop;
 237         else
 238                 fun->chip_delay = 50;
 239
 240         fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
 241                                           io_res.end - io_res.start + 1);
 242         if (!fun->io_base) {
 243                 ret = -ENOMEM;
 244                 goto err2;
 245         }
 246
 247         fun->dev = &ofdev->dev;
 248         fun->last_ctrl = NAND_CLE;
 249
 250         ret = fun_chip_init(fun, ofdev->node, &io_res);
 251         if (ret)
 252                 goto err2;
 253
 254         dev_set_drvdata(&ofdev->dev, fun);
 255
 256         return 0;
 257 err2:
 258         if (fun->rnb_gpio >= 0)
 259                 gpio_free(fun->rnb_gpio);
 260 err1:
 261         kfree(fun);
 262
 263         return ret;
 264 }
 265
 266 static int __devexit fun_remove(struct of_device *ofdev)
 267 {
 268         struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
 269
 270         nand_release(&fun->mtd);
 271         kfree(fun->mtd.name);
 272
 273         if (fun->rnb_gpio >= 0)
 274                 gpio_free(fun->rnb_gpio);
 275
 276         kfree(fun);
 277
 278         return 0;
 279 }
 280
 281 static struct of_device_id of_fun_match[] = {
 282         { .compatible = "fsl,upm-nand" },
 283         {},
 284 };
 285 MODULE_DEVICE_TABLE(of, of_fun_match);
 286
 287 static struct of_platform_driver of_fun_driver = {
 288         .name           = "fsl,upm-nand",
 289         .match_table    = of_fun_match,
 290         .probe          = fun_probe,
 291         .remove         = __devexit_p(fun_remove),
 292 };
 293
 294 static int __init fun_module_init(void)
 295 {
 296         return of_register_platform_driver(&of_fun_driver);
 297 }
 298 module_init(fun_module_init);
 299
 300 static void __exit fun_module_exit(void)
 301 {
 302         of_unregister_platform_driver(&of_fun_driver);
 303 }
 304 module_exit(fun_module_exit);
 305
 306 MODULE_LICENSE("GPL");
 307 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
 308 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
 309                    "LocalBus User-Programmable Machine");