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 };
  40
  41 #define to_fsl_upm_nand(mtd) container_of(mtd, struct fsl_upm_nand, mtd)
  42
  43 static int fun_chip_ready(struct mtd_info *mtd)
  44 {
  45         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  46
  47         if (gpio_get_value(fun->rnb_gpio))
  48                 return 1;
  49
  50         dev_vdbg(fun->dev, "busy\n");
  51         return 0;
  52 }
  53
  54 static void fun_wait_rnb(struct fsl_upm_nand *fun)
  55 {
  56         int cnt = 1000000;
  57
  58         if (fun->rnb_gpio >= 0) {
  59                 while (--cnt && !fun_chip_ready(&fun->mtd))
  60                         cpu_relax();
  61         }
  62
  63         if (!cnt)
  64                 dev_err(fun->dev, "tired waiting for RNB\n");
  65 }
  66
  67 static void fun_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  68 {
  69         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  70
  71         if (!(ctrl & fun->last_ctrl)) {
  72                 fsl_upm_end_pattern(&fun->upm);
  73
  74                 if (cmd == NAND_CMD_NONE)
  75                         return;
  76
  77                 fun->last_ctrl = ctrl & (NAND_ALE | NAND_CLE);
  78         }
  79
  80         if (ctrl & NAND_CTRL_CHANGE) {
  81                 if (ctrl & NAND_ALE)
  82                         fsl_upm_start_pattern(&fun->upm, fun->upm_addr_offset);
  83                 else if (ctrl & NAND_CLE)
  84                         fsl_upm_start_pattern(&fun->upm, fun->upm_cmd_offset);
  85         }
  86
  87         fsl_upm_run_pattern(&fun->upm, fun->io_base, cmd);
  88
  89         fun_wait_rnb(fun);
  90 }
  91
  92 static uint8_t fun_read_byte(struct mtd_info *mtd)
  93 {
  94         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
  95
  96         return in_8(fun->chip.IO_ADDR_R);
  97 }
  98
  99 static void fun_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 100 {
 101         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 102         int i;
 103
 104         for (i = 0; i < len; i++)
 105                 buf[i] = in_8(fun->chip.IO_ADDR_R);
 106 }
 107
 108 static void fun_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 109 {
 110         struct fsl_upm_nand *fun = to_fsl_upm_nand(mtd);
 111         int i;
 112
 113         for (i = 0; i < len; i++) {
 114                 out_8(fun->chip.IO_ADDR_W, buf[i]);
 115                 fun_wait_rnb(fun);
 116         }
 117 }
 118
 119 static int __devinit fun_chip_init(struct fsl_upm_nand *fun,
 120                                    const struct device_node *upm_np,
 121                                    const struct resource *io_res)
 122 {
 123         int ret;
 124         struct device_node *flash_np;
 125 #ifdef CONFIG_MTD_PARTITIONS
 126         static const char *part_types[] = { "cmdlinepart", NULL, };
 127 #endif
 128
 129         fun->chip.IO_ADDR_R = fun->io_base;
 130         fun->chip.IO_ADDR_W = fun->io_base;
 131         fun->chip.cmd_ctrl = fun_cmd_ctrl;
 132         fun->chip.chip_delay = 50;
 133         fun->chip.read_byte = fun_read_byte;
 134         fun->chip.read_buf = fun_read_buf;
 135         fun->chip.write_buf = fun_write_buf;
 136         fun->chip.ecc.mode = NAND_ECC_SOFT;
 137
 138         if (fun->rnb_gpio >= 0)
 139                 fun->chip.dev_ready = fun_chip_ready;
 140
 141         fun->mtd.priv = &fun->chip;
 142         fun->mtd.owner = THIS_MODULE;
 143
 144         flash_np = of_get_next_child(upm_np, NULL);
 145         if (!flash_np)
 146                 return -ENODEV;
 147
 148         fun->mtd.name = kasprintf(GFP_KERNEL, "%x.%s", io_res->start,
 149                                   flash_np->name);
 150         if (!fun->mtd.name) {
 151                 ret = -ENOMEM;
 152                 goto err;
 153         }
 154
 155         ret = nand_scan(&fun->mtd, 1);
 156         if (ret)
 157                 goto err;
 158
 159 #ifdef CONFIG_MTD_PARTITIONS
 160         ret = parse_mtd_partitions(&fun->mtd, part_types, &fun->parts, 0);
 161
 162 #ifdef CONFIG_MTD_OF_PARTS
 163         if (ret == 0)
 164                 ret = of_mtd_parse_partitions(fun->dev, &fun->mtd,
 165                                               flash_np, &fun->parts);
 166 #endif
 167         if (ret > 0)
 168                 ret = add_mtd_partitions(&fun->mtd, fun->parts, ret);
 169         else
 170 #endif
 171                 ret = add_mtd_device(&fun->mtd);
 172 err:
 173         of_node_put(flash_np);
 174         return ret;
 175 }
 176
 177 static int __devinit fun_probe(struct of_device *ofdev,
 178                                const struct of_device_id *ofid)
 179 {
 180         struct fsl_upm_nand *fun;
 181         struct resource io_res;
 182         const uint32_t *prop;
 183         int ret;
 184         int size;
 185
 186         fun = kzalloc(sizeof(*fun), GFP_KERNEL);
 187         if (!fun)
 188                 return -ENOMEM;
 189
 190         ret = of_address_to_resource(ofdev->node, 0, &io_res);
 191         if (ret) {
 192                 dev_err(&ofdev->dev, "can't get IO base\n");
 193                 goto err1;
 194         }
 195
 196         ret = fsl_upm_find(io_res.start, &fun->upm);
 197         if (ret) {
 198                 dev_err(&ofdev->dev, "can't find UPM\n");
 199                 goto err1;
 200         }
 201
 202         prop = of_get_property(ofdev->node, "fsl,upm-addr-offset", &size);
 203         if (!prop || size != sizeof(uint32_t)) {
 204                 dev_err(&ofdev->dev, "can't get UPM address offset\n");
 205                 ret = -EINVAL;
 206                 goto err2;
 207         }
 208         fun->upm_addr_offset = *prop;
 209
 210         prop = of_get_property(ofdev->node, "fsl,upm-cmd-offset", &size);
 211         if (!prop || size != sizeof(uint32_t)) {
 212                 dev_err(&ofdev->dev, "can't get UPM command offset\n");
 213                 ret = -EINVAL;
 214                 goto err2;
 215         }
 216         fun->upm_cmd_offset = *prop;
 217
 218         fun->rnb_gpio = of_get_gpio(ofdev->node, 0);
 219         if (fun->rnb_gpio >= 0) {
 220                 ret = gpio_request(fun->rnb_gpio, ofdev->dev.bus_id);
 221                 if (ret) {
 222                         dev_err(&ofdev->dev, "can't request RNB gpio\n");
 223                         goto err2;
 224                 }
 225                 gpio_direction_input(fun->rnb_gpio);
 226         } else if (fun->rnb_gpio == -EINVAL) {
 227                 dev_err(&ofdev->dev, "specified RNB gpio is invalid\n");
 228                 goto err2;
 229         }
 230
 231         fun->io_base = devm_ioremap_nocache(&ofdev->dev, io_res.start,
 232                                           io_res.end - io_res.start + 1);
 233         if (!fun->io_base) {
 234                 ret = -ENOMEM;
 235                 goto err2;
 236         }
 237
 238         fun->dev = &ofdev->dev;
 239         fun->last_ctrl = NAND_CLE;
 240
 241         ret = fun_chip_init(fun, ofdev->node, &io_res);
 242         if (ret)
 243                 goto err2;
 244
 245         dev_set_drvdata(&ofdev->dev, fun);
 246
 247         return 0;
 248 err2:
 249         if (fun->rnb_gpio >= 0)
 250                 gpio_free(fun->rnb_gpio);
 251 err1:
 252         kfree(fun);
 253
 254         return ret;
 255 }
 256
 257 static int __devexit fun_remove(struct of_device *ofdev)
 258 {
 259         struct fsl_upm_nand *fun = dev_get_drvdata(&ofdev->dev);
 260
 261         nand_release(&fun->mtd);
 262         kfree(fun->mtd.name);
 263
 264         if (fun->rnb_gpio >= 0)
 265                 gpio_free(fun->rnb_gpio);
 266
 267         kfree(fun);
 268
 269         return 0;
 270 }
 271
 272 static struct of_device_id of_fun_match[] = {
 273         { .compatible = "fsl,upm-nand" },
 274         {},
 275 };
 276 MODULE_DEVICE_TABLE(of, of_fun_match);
 277
 278 static struct of_platform_driver of_fun_driver = {
 279         .name           = "fsl,upm-nand",
 280         .match_table    = of_fun_match,
 281         .probe          = fun_probe,
 282         .remove         = __devexit_p(fun_remove),
 283 };
 284
 285 static int __init fun_module_init(void)
 286 {
 287         return of_register_platform_driver(&of_fun_driver);
 288 }
 289 module_init(fun_module_init);
 290
 291 static void __exit fun_module_exit(void)
 292 {
 293         of_unregister_platform_driver(&of_fun_driver);
 294 }
 295 module_exit(fun_module_exit);
 296
 297 MODULE_LICENSE("GPL");
 298 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
 299 MODULE_DESCRIPTION("Driver for NAND chips working through Freescale "
 300                    "LocalBus User-Programmable Machine");