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 };
  25
  26 static const char *part_probe_types[] = { "cmdlinepart", NULL };
  27
  28 /*
  29  * Probe for the NAND device.
  30  */
  31 static int plat_nand_probe(struct platform_device *pdev)
  32 {
  33         struct platform_nand_data *pdata = pdev->dev.platform_data;
  34         struct mtd_part_parser_data ppdata;
  35         struct plat_nand_data *data;
  36         struct resource *res;
  37         const char **part_types;
  38         int err = 0;
  39
  40         if (!pdata) {
  41                 dev_err(&pdev->dev, "platform_nand_data is missing\n");
  42                 return -EINVAL;
  43         }
  44
  45         if (pdata->chip.nr_chips < 1) {
  46                 dev_err(&pdev->dev, "invalid number of chips specified\n");
  47                 return -EINVAL;
  48         }
  49
  50         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  51         if (!res)
  52                 return -ENXIO;
  53
  54         /* Allocate memory for the device structure (and zero it) */
  55         data = kzalloc(sizeof(struct plat_nand_data), GFP_KERNEL);
  56         if (!data) {
  57                 dev_err(&pdev->dev, "failed to allocate device structure.\n");
  58                 return -ENOMEM;
  59         }
  60
  61         if (!request_mem_region(res->start, resource_size(res),
  62                                 dev_name(&pdev->dev))) {
  63                 dev_err(&pdev->dev, "request_mem_region failed\n");
  64                 err = -EBUSY;
  65                 goto out_free;
  66         }
  67
  68         data->io_base = ioremap(res->start, resource_size(res));
  69         if (data->io_base == NULL) {
  70                 dev_err(&pdev->dev, "ioremap failed\n");
  71                 err = -EIO;
  72                 goto out_release_io;
  73         }
  74
  75         data->chip.priv = &data;
  76         data->mtd.priv = &data->chip;
  77         data->mtd.owner = THIS_MODULE;
  78         data->mtd.name = dev_name(&pdev->dev);
  79
  80         data->chip.IO_ADDR_R = data->io_base;
  81         data->chip.IO_ADDR_W = data->io_base;
  82         data->chip.cmd_ctrl = pdata->ctrl.cmd_ctrl;
  83         data->chip.dev_ready = pdata->ctrl.dev_ready;
  84         data->chip.select_chip = pdata->ctrl.select_chip;
  85         data->chip.write_buf = pdata->ctrl.write_buf;
  86         data->chip.read_buf = pdata->ctrl.read_buf;
  87         data->chip.read_byte = pdata->ctrl.read_byte;
  88         data->chip.chip_delay = pdata->chip.chip_delay;
  89         data->chip.options |= pdata->chip.options;
  90         data->chip.bbt_options |= pdata->chip.bbt_options;
  91
  92         data->chip.ecc.hwctl = pdata->ctrl.hwcontrol;
  93         data->chip.ecc.layout = pdata->chip.ecclayout;
  94         data->chip.ecc.mode = NAND_ECC_SOFT;
  95
  96         platform_set_drvdata(pdev, data);
  97
  98         /* Handle any platform specific setup */
  99         if (pdata->ctrl.probe) {
 100                 err = pdata->ctrl.probe(pdev);
 101                 if (err)
 102                         goto out;
 103         }
 104
 105         /* Scan to find existence of the device */
 106         if (nand_scan(&data->mtd, pdata->chip.nr_chips)) {
 107                 err = -ENXIO;
 108                 goto out;
 109         }
 110
 111         part_types = pdata->chip.part_probe_types ? : part_probe_types;
 112
 113         ppdata.of_node = pdev->dev.of_node;
 114         err = mtd_device_parse_register(&data->mtd, part_types, &ppdata,
 115                                         pdata->chip.partitions,
 116                                         pdata->chip.nr_partitions);
 117
 118         if (!err)
 119                 return err;
 120
 121         nand_release(&data->mtd);
 122 out:
 123         if (pdata->ctrl.remove)
 124                 pdata->ctrl.remove(pdev);
 125         platform_set_drvdata(pdev, NULL);
 126         iounmap(data->io_base);
 127 out_release_io:
 128         release_mem_region(res->start, resource_size(res));
 129 out_free:
 130         kfree(data);
 131         return err;
 132 }
 133
 134 /*
 135  * Remove a NAND device.
 136  */
 137 static int plat_nand_remove(struct platform_device *pdev)
 138 {
 139         struct plat_nand_data *data = platform_get_drvdata(pdev);
 140         struct platform_nand_data *pdata = pdev->dev.platform_data;
 141         struct resource *res;
 142
 143         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 144
 145         nand_release(&data->mtd);
 146         if (pdata->ctrl.remove)
 147                 pdata->ctrl.remove(pdev);
 148         iounmap(data->io_base);
 149         release_mem_region(res->start, resource_size(res));
 150         kfree(data);
 151
 152         return 0;
 153 }
 154
 155 static const struct of_device_id plat_nand_match[] = {
 156         { .compatible = "gen_nand" },
 157         {},
 158 };
 159 MODULE_DEVICE_TABLE(of, plat_nand_match);
 160
 161 static struct platform_driver plat_nand_driver = {
 162         .probe  = plat_nand_probe,
 163         .remove = plat_nand_remove,
 164         .driver = {
 165                 .name           = "gen_nand",
 166                 .owner          = THIS_MODULE,
 167                 .of_match_table = plat_nand_match,
 168         },
 169 };
 170
 171 module_platform_driver(plat_nand_driver);
 172
 173 MODULE_LICENSE("GPL");
 174 MODULE_AUTHOR("Vitaly Wool");
 175 MODULE_DESCRIPTION("Simple generic NAND driver");
 176 MODULE_ALIAS("platform:gen_nand");