drivers/mtd/nand/plat_nand.c

   1 /*
   2  * Generic NAND driver
   3  *
   4  * Author: Vitaly Wool <vitalywool@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  */
  11
  12 #include <linux/io.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/slab.h>
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/mtd/nand.h>
  18 #include <linux/mtd/partitions.h>
  19
  20 struct plat_nand_data {
  21         struct nand_chip        chip;
  22         struct mtd_info         mtd;
  23         void __iomem            *io_base;
  24 #ifdef CONFIG_MTD_PARTITIONS
  25         int                     nr_parts;
  26         struct mtd_partition    *parts;
  27 #endif
  28 };
  29
  30 /*
  31  * Probe for the NAND device.
  32  */
  33 static int __init plat_nand_probe(struct platform_device *pdev)
  34 {
  35         struct platform_nand_data *pdata = pdev->dev.platform_data;
  36         struct plat_nand_data *data;
  37         int res = 0;
  38
  39         /* Allocate memory for the device structure (and zero it) */
  40         data = kzalloc(sizeof(struct plat_nand_data), GFP_KERNEL);
  41         if (!data) {
  42                 dev_err(&pdev->dev, "failed to allocate device structure.\n");
  43                 return -ENOMEM;
  44         }
  45
  46         data->io_base = ioremap(pdev->resource[0].start,
  47                                 pdev->resource[0].end - pdev->resource[0].start + 1);
  48         if (data->io_base == NULL) {
  49                 dev_err(&pdev->dev, "ioremap failed\n");
  50                 kfree(data);
  51                 return -EIO;
  52         }
  53
  54         data->chip.priv = &data;
  55         data->mtd.priv = &data->chip;
  56         data->mtd.owner = THIS_MODULE;
  57         data->mtd.name = pdev->dev.bus_id;
  58
  59         data->chip.IO_ADDR_R = data->io_base;
  60         data->chip.IO_ADDR_W = data->io_base;
  61         data->chip.cmd_ctrl = pdata->ctrl.cmd_ctrl;
  62         data->chip.dev_ready = pdata->ctrl.dev_ready;
  63         data->chip.select_chip = pdata->ctrl.select_chip;
  64         data->chip.chip_delay = pdata->chip.chip_delay;
  65         data->chip.options |= pdata->chip.options;
  66
  67         data->chip.ecc.hwctl = pdata->ctrl.hwcontrol;
  68         data->chip.ecc.layout = pdata->chip.ecclayout;
  69         data->chip.ecc.mode = NAND_ECC_SOFT;
  70
  71         platform_set_drvdata(pdev, data);
  72
  73         /* Scan to find existance of the device */
  74         if (nand_scan(&data->mtd, 1)) {
  75                 res = -ENXIO;
  76                 goto out;
  77         }
  78
  79 #ifdef CONFIG_MTD_PARTITIONS
  80         if (pdata->chip.part_probe_types) {
  81                 res = parse_mtd_partitions(&data->mtd,
  82                                         pdata->chip.part_probe_types,
  83                                         &data->parts, 0);
  84                 if (res > 0) {
  85                         add_mtd_partitions(&data->mtd, data->parts, res);
  86                         return 0;
  87                 }
  88         }
  89         if (pdata->chip.partitions) {
  90                 data->parts = pdata->chip.partitions;
  91                 res = add_mtd_partitions(&data->mtd, data->parts,
  92                         pdata->chip.nr_partitions);
  93         } else
  94 #endif
  95         res = add_mtd_device(&data->mtd);
  96
  97         if (!res)
  98                 return res;
  99
 100         nand_release(&data->mtd);
 101 out:
 102         platform_set_drvdata(pdev, NULL);
 103         iounmap(data->io_base);
 104         kfree(data);
 105         return res;
 106 }
 107
 108 /*
 109  * Remove a NAND device.
 110  */
 111 static int __devexit plat_nand_remove(struct platform_device *pdev)
 112 {
 113         struct plat_nand_data *data = platform_get_drvdata(pdev);
 114 #ifdef CONFIG_MTD_PARTITIONS
 115         struct platform_nand_data *pdata = pdev->dev.platform_data;
 116 #endif
 117
 118         nand_release(&data->mtd);
 119 #ifdef CONFIG_MTD_PARTITIONS
 120         if (data->parts && data->parts != pdata->chip.partitions)
 121                 kfree(data->parts);
 122 #endif
 123         iounmap(data->io_base);
 124         kfree(data);
 125
 126         return 0;
 127 }
 128
 129 static struct platform_driver plat_nand_driver = {
 130         .probe          = plat_nand_probe,
 131         .remove         = plat_nand_remove,
 132         .driver         = {
 133                 .name   = "gen_nand",
 134                 .owner  = THIS_MODULE,
 135         },
 136 };
 137
 138 static int __init plat_nand_init(void)
 139 {
 140         return platform_driver_register(&plat_nand_driver);
 141 }
 142
 143 static void __exit plat_nand_exit(void)
 144 {
 145         platform_driver_unregister(&plat_nand_driver);
 146 }
 147
 148 module_init(plat_nand_init);
 149 module_exit(plat_nand_exit);
 150
 151 MODULE_LICENSE("GPL");
 152 MODULE_AUTHOR("Vitaly Wool");
 153 MODULE_DESCRIPTION("Simple generic NAND driver");
 154 MODULE_ALIAS("platform:gen_nand");