drivers/mtd/nand/denali_dt.c

   1 /*
   2  * NAND Flash Controller Device Driver for DT
   3  *
   4  * Copyright © 2011, Picochip.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15 #include <linux/clk.h>
  16 #include <linux/err.h>
  17 #include <linux/io.h>
  18 #include <linux/ioport.h>
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/of.h>
  23 #include <linux/of_device.h>
  24 #include <linux/slab.h>
  25
  26 #include "denali.h"
  27
  28 struct denali_dt {
  29         struct denali_nand_info denali;
  30         struct clk              *clk;
  31 };
  32
  33 static void __iomem *request_and_map(struct device *dev,
  34                                      const struct resource *res)
  35 {
  36         void __iomem *ptr;
  37
  38         if (!devm_request_mem_region(dev, res->start, resource_size(res),
  39                                      "denali-dt")) {
  40                 dev_err(dev, "unable to request %s\n", res->name);
  41                 return NULL;
  42         }
  43
  44         ptr = devm_ioremap_nocache(dev, res->start, resource_size(res));
  45         if (!ptr)
  46                 dev_err(dev, "ioremap_nocache of %s failed!", res->name);
  47
  48         return ptr;
  49 }
  50
  51 static const struct of_device_id denali_nand_dt_ids[] = {
  52                 { .compatible = "denali,denali-nand-dt" },
  53                 { /* sentinel */ }
  54         };
  55
  56 MODULE_DEVICE_TABLE(of, denali_nand_dt_ids);
  57
  58 static u64 denali_dma_mask;
  59
  60 static int denali_dt_probe(struct platform_device *ofdev)
  61 {
  62         struct resource *denali_reg, *nand_data;
  63         struct denali_dt *dt;
  64         struct denali_nand_info *denali;
  65         int ret;
  66         const struct of_device_id *of_id;
  67
  68         of_id = of_match_device(denali_nand_dt_ids, &ofdev->dev);
  69         if (of_id) {
  70                 ofdev->id_entry = of_id->data;
  71         } else {
  72                 pr_err("Failed to find the right device id.\n");
  73                 return -ENOMEM;
  74         }
  75
  76         dt = devm_kzalloc(&ofdev->dev, sizeof(*dt), GFP_KERNEL);
  77         if (!dt)
  78                 return -ENOMEM;
  79         denali = &dt->denali;
  80
  81         denali_reg = platform_get_resource_byname(ofdev, IORESOURCE_MEM, "denali_reg");
  82         nand_data = platform_get_resource_byname(ofdev, IORESOURCE_MEM, "nand_data");
  83         if (!denali_reg || !nand_data) {
  84                 dev_err(&ofdev->dev, "resources not completely defined\n");
  85                 return -EINVAL;
  86         }
  87
  88         denali->platform = DT;
  89         denali->dev = &ofdev->dev;
  90         denali->irq = platform_get_irq(ofdev, 0);
  91         if (denali->irq < 0) {
  92                 dev_err(&ofdev->dev, "no irq defined\n");
  93                 return denali->irq;
  94         }
  95
  96         denali->flash_reg = request_and_map(&ofdev->dev, denali_reg);
  97         if (!denali->flash_reg)
  98                 return -ENOMEM;
  99
 100         denali->flash_mem = request_and_map(&ofdev->dev, nand_data);
 101         if (!denali->flash_mem)
 102                 return -ENOMEM;
 103
 104         if (!of_property_read_u32(ofdev->dev.of_node,
 105                 "dma-mask", (u32 *)&denali_dma_mask)) {
 106                 denali->dev->dma_mask = &denali_dma_mask;
 107         } else {
 108                 denali->dev->dma_mask = NULL;
 109         }
 110
 111         dt->clk = clk_get(&ofdev->dev, NULL);
 112         if (IS_ERR(dt->clk)) {
 113                 dev_err(&ofdev->dev, "no clk available\n");
 114                 return PTR_ERR(dt->clk);
 115         }
 116         clk_prepare_enable(dt->clk);
 117
 118         ret = denali_init(denali);
 119         if (ret)
 120                 goto out_disable_clk;
 121
 122         platform_set_drvdata(ofdev, dt);
 123         return 0;
 124
 125 out_disable_clk:
 126         clk_disable_unprepare(dt->clk);
 127         clk_put(dt->clk);
 128
 129         return ret;
 130 }
 131
 132 static int denali_dt_remove(struct platform_device *ofdev)
 133 {
 134         struct denali_dt *dt = platform_get_drvdata(ofdev);
 135
 136         denali_remove(&dt->denali);
 137         clk_disable(dt->clk);
 138         clk_put(dt->clk);
 139
 140         return 0;
 141 }
 142
 143 static struct platform_driver denali_dt_driver = {
 144         .probe          = denali_dt_probe,
 145         .remove         = denali_dt_remove,
 146         .driver         = {
 147                 .name   = "denali-nand-dt",
 148                 .owner  = THIS_MODULE,
 149                 .of_match_table = denali_nand_dt_ids,
 150         },
 151 };
 152
 153 module_platform_driver(denali_dt_driver);
 154
 155 MODULE_LICENSE("GPL");
 156 MODULE_AUTHOR("Jamie Iles");
 157 MODULE_DESCRIPTION("DT driver for Denali NAND controller");