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/err.h>
  13 #include <linux/io.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/slab.h>
  17 #include <linux/mtd/mtd.h>
  18 #include <linux/mtd/nand.h>
  19 #include <linux/mtd/partitions.h>
  20
  21 struct plat_nand_data {
  22         struct nand_chip        chip;
  23         void __iomem            *io_base;
  24 };
  25
  26 /*
  27  * Probe for the NAND device.
  28  */
  29 static int plat_nand_probe(struct platform_device *pdev)
  30 {
  31         struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev);
  32         struct plat_nand_data *data;
  33         struct mtd_info *mtd;
  34         struct resource *res;
  35         const char **part_types;
  36         int err = 0;
  37
  38         if (!pdata) {
  39                 dev_err(&pdev->dev, "platform_nand_data is missing\n");
  40                 return -EINVAL;
  41         }
  42
  43         if (pdata->chip.nr_chips < 1) {
  44                 dev_err(&pdev->dev, "invalid number of chips specified\n");
  45                 return -EINVAL;
  46         }
  47
  48         /* Allocate memory for the device structure (and zero it) */
  49         data = devm_kzalloc(&pdev->dev, sizeof(struct plat_nand_data),
  50                             GFP_KERNEL);
  51         if (!data)
  52                 return -ENOMEM;
  53
  54         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  55         data->io_base = devm_ioremap_resource(&pdev->dev, res);
  56         if (IS_ERR(data->io_base))
  57                 return PTR_ERR(data->io_base);
  58
  59         nand_set_flash_node(&data->chip, pdev->dev.of_node);
  60         mtd = nand_to_mtd(&data->chip);
  61         mtd->dev.parent = &pdev->dev;
  62
  63         data->chip.IO_ADDR_R = data->io_base;
  64         data->chip.IO_ADDR_W = data->io_base;
  65         data->chip.cmd_ctrl = pdata->ctrl.cmd_ctrl;
  66         data->chip.dev_ready = pdata->ctrl.dev_ready;
  67         data->chip.select_chip = pdata->ctrl.select_chip;
  68         data->chip.write_buf = pdata->ctrl.write_buf;
  69         data->chip.read_buf = pdata->ctrl.read_buf;
  70         data->chip.read_byte = pdata->ctrl.read_byte;
  71         data->chip.chip_delay = pdata->chip.chip_delay;
  72         data->chip.options |= pdata->chip.options;
  73         data->chip.bbt_options |= pdata->chip.bbt_options;
  74
  75         data->chip.ecc.hwctl = pdata->ctrl.hwcontrol;
  76         data->chip.ecc.mode = NAND_ECC_SOFT;
  77         data->chip.ecc.algo = NAND_ECC_HAMMING;
  78
  79         platform_set_drvdata(pdev, data);
  80
  81         /* Handle any platform specific setup */
  82         if (pdata->ctrl.probe) {
  83                 err = pdata->ctrl.probe(pdev);
  84                 if (err)
  85                         goto out;
  86         }
  87
  88         /* Scan to find existence of the device */
  89         if (nand_scan(mtd, pdata->chip.nr_chips)) {
  90                 err = -ENXIO;
  91                 goto out;
  92         }
  93
  94         part_types = pdata->chip.part_probe_types;
  95
  96         err = mtd_device_parse_register(mtd, part_types, NULL,
  97                                         pdata->chip.partitions,
  98                                         pdata->chip.nr_partitions);
  99
 100         if (!err)
 101                 return err;
 102
 103         nand_release(mtd);
 104 out:
 105         if (pdata->ctrl.remove)
 106                 pdata->ctrl.remove(pdev);
 107         return err;
 108 }
 109
 110 /*
 111  * Remove a NAND device.
 112  */
 113 static int plat_nand_remove(struct platform_device *pdev)
 114 {
 115         struct plat_nand_data *data = platform_get_drvdata(pdev);
 116         struct platform_nand_data *pdata = dev_get_platdata(&pdev->dev);
 117
 118         nand_release(nand_to_mtd(&data->chip));
 119         if (pdata->ctrl.remove)
 120                 pdata->ctrl.remove(pdev);
 121
 122         return 0;
 123 }
 124
 125 static const struct of_device_id plat_nand_match[] = {
 126         { .compatible = "gen_nand" },
 127         {},
 128 };
 129 MODULE_DEVICE_TABLE(of, plat_nand_match);
 130
 131 static struct platform_driver plat_nand_driver = {
 132         .probe  = plat_nand_probe,
 133         .remove = plat_nand_remove,
 134         .driver = {
 135                 .name           = "gen_nand",
 136                 .of_match_table = plat_nand_match,
 137         },
 138 };
 139
 140 module_platform_driver(plat_nand_driver);
 141
 142 MODULE_LICENSE("GPL");
 143 MODULE_AUTHOR("Vitaly Wool");
 144 MODULE_DESCRIPTION("Simple generic NAND driver");
 145 MODULE_ALIAS("platform:gen_nand");