drivers/mtd/nand/nomadik_nand.c

   1 /*
   2  *  drivers/mtd/nand/nomadik_nand.c
   3  *
   4  *  Overview:
   5  *      Driver for on-board NAND flash on Nomadik Platforms
   6  *
   7  * Copyright © 2007 STMicroelectronics Pvt. Ltd.
   8  * Author: Sachin Verma <sachin.verma@st.com>
   9  *
  10  * Copyright © 2009 Alessandro Rubini
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/types.h>
  27 #include <linux/mtd/mtd.h>
  28 #include <linux/mtd/nand.h>
  29 #include <linux/mtd/nand_ecc.h>
  30 #include <linux/platform_device.h>
  31 #include <linux/mtd/partitions.h>
  32 #include <linux/io.h>
  33 #include <linux/slab.h>
  34 #include <mach/nand.h>
  35 #include <mach/fsmc.h>
  36
  37 #include <mtd/mtd-abi.h>
  38
  39 struct nomadik_nand_host {
  40         struct mtd_info         mtd;
  41         struct nand_chip        nand;
  42         void __iomem *data_va;
  43         void __iomem *cmd_va;
  44         void __iomem *addr_va;
  45         struct nand_bbt_descr *bbt_desc;
  46 };
  47
  48 static struct nand_ecclayout nomadik_ecc_layout = {
  49         .eccbytes = 3 * 4,
  50         .eccpos = { /* each subpage has 16 bytes: pos 2,3,4 hosts ECC */
  51                 0x02, 0x03, 0x04,
  52                 0x12, 0x13, 0x14,
  53                 0x22, 0x23, 0x24,
  54                 0x32, 0x33, 0x34},
  55         /* let's keep bytes 5,6,7 for us, just in case we change ECC algo */
  56         .oobfree = { {0x08, 0x08}, {0x18, 0x08}, {0x28, 0x08}, {0x38, 0x08} },
  57 };
  58
  59 static void nomadik_ecc_control(struct mtd_info *mtd, int mode)
  60 {
  61         /* No need to enable hw ecc, it's on by default */
  62 }
  63
  64 static void nomadik_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  65 {
  66         struct nand_chip *nand = mtd->priv;
  67         struct nomadik_nand_host *host = nand->priv;
  68
  69         if (cmd == NAND_CMD_NONE)
  70                 return;
  71
  72         if (ctrl & NAND_CLE)
  73                 writeb(cmd, host->cmd_va);
  74         else
  75                 writeb(cmd, host->addr_va);
  76 }
  77
  78 static int nomadik_nand_probe(struct platform_device *pdev)
  79 {
  80         struct nomadik_nand_platform_data *pdata = pdev->dev.platform_data;
  81         struct nomadik_nand_host *host;
  82         struct mtd_info *mtd;
  83         struct nand_chip *nand;
  84         struct resource *res;
  85         int ret = 0;
  86
  87         /* Allocate memory for the device structure (and zero it) */
  88         host = kzalloc(sizeof(struct nomadik_nand_host), GFP_KERNEL);
  89         if (!host) {
  90                 dev_err(&pdev->dev, "Failed to allocate device structure.\n");
  91                 return -ENOMEM;
  92         }
  93
  94         /* Call the client's init function, if any */
  95         if (pdata->init)
  96                 ret = pdata->init();
  97         if (ret < 0) {
  98                 dev_err(&pdev->dev, "Init function failed\n");
  99                 goto err;
 100         }
 101
 102         /* ioremap three regions */
 103         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_addr");
 104         if (!res) {
 105                 ret = -EIO;
 106                 goto err_unmap;
 107         }
 108         host->addr_va = ioremap(res->start, resource_size(res));
 109
 110         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_data");
 111         if (!res) {
 112                 ret = -EIO;
 113                 goto err_unmap;
 114         }
 115         host->data_va = ioremap(res->start, resource_size(res));
 116
 117         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "nand_cmd");
 118         if (!res) {
 119                 ret = -EIO;
 120                 goto err_unmap;
 121         }
 122         host->cmd_va = ioremap(res->start, resource_size(res));
 123
 124         if (!host->addr_va || !host->data_va || !host->cmd_va) {
 125                 ret = -ENOMEM;
 126                 goto err_unmap;
 127         }
 128
 129         /* Link all private pointers */
 130         mtd = &host->mtd;
 131         nand = &host->nand;
 132         mtd->priv = nand;
 133         nand->priv = host;
 134
 135         host->mtd.owner = THIS_MODULE;
 136         nand->IO_ADDR_R = host->data_va;
 137         nand->IO_ADDR_W = host->data_va;
 138         nand->cmd_ctrl = nomadik_cmd_ctrl;
 139
 140         /*
 141          * This stanza declares ECC_HW but uses soft routines. It's because
 142          * HW claims to make the calculation but not the correction. However,
 143          * I haven't managed to get the desired data out of it until now.
 144          */
 145         nand->ecc.mode = NAND_ECC_SOFT;
 146         nand->ecc.layout = &nomadik_ecc_layout;
 147         nand->ecc.hwctl = nomadik_ecc_control;
 148         nand->ecc.size = 512;
 149         nand->ecc.bytes = 3;
 150
 151         nand->options = pdata->options;
 152
 153         /*
 154          * Scan to find existence of the device
 155          */
 156         if (nand_scan(&host->mtd, 1)) {
 157                 ret = -ENXIO;
 158                 goto err_unmap;
 159         }
 160
 161         mtd_device_register(&host->mtd, pdata->parts, pdata->nparts);
 162
 163         platform_set_drvdata(pdev, host);
 164         return 0;
 165
 166  err_unmap:
 167         if (host->cmd_va)
 168                 iounmap(host->cmd_va);
 169         if (host->data_va)
 170                 iounmap(host->data_va);
 171         if (host->addr_va)
 172                 iounmap(host->addr_va);
 173  err:
 174         kfree(host);
 175         return ret;
 176 }
 177
 178 /*
 179  * Clean up routine
 180  */
 181 static int nomadik_nand_remove(struct platform_device *pdev)
 182 {
 183         struct nomadik_nand_host *host = platform_get_drvdata(pdev);
 184         struct nomadik_nand_platform_data *pdata = pdev->dev.platform_data;
 185
 186         if (pdata->exit)
 187                 pdata->exit();
 188
 189         if (host) {
 190                 nand_release(&host->mtd);
 191                 iounmap(host->cmd_va);
 192                 iounmap(host->data_va);
 193                 iounmap(host->addr_va);
 194                 kfree(host);
 195         }
 196         return 0;
 197 }
 198
 199 static int nomadik_nand_suspend(struct device *dev)
 200 {
 201         struct nomadik_nand_host *host = dev_get_drvdata(dev);
 202         int ret = 0;
 203         if (host)
 204                 ret = mtd_suspend(&host->mtd);
 205         return ret;
 206 }
 207
 208 static int nomadik_nand_resume(struct device *dev)
 209 {
 210         struct nomadik_nand_host *host = dev_get_drvdata(dev);
 211         if (host)
 212                 mtd_resume(&host->mtd);
 213         return 0;
 214 }
 215
 216 static const struct dev_pm_ops nomadik_nand_pm_ops = {
 217         .suspend = nomadik_nand_suspend,
 218         .resume = nomadik_nand_resume,
 219 };
 220
 221 static struct platform_driver nomadik_nand_driver = {
 222         .probe = nomadik_nand_probe,
 223         .remove = nomadik_nand_remove,
 224         .driver = {
 225                 .owner = THIS_MODULE,
 226                 .name = "nomadik_nand",
 227                 .pm = &nomadik_nand_pm_ops,
 228         },
 229 };
 230
 231 module_platform_driver(nomadik_nand_driver);
 232
 233 MODULE_LICENSE("GPL");
 234 MODULE_AUTHOR("ST Microelectronics (sachin.verma@st.com)");
 235 MODULE_DESCRIPTION("NAND driver for Nomadik Platform");