arch/mips/lantiq/xway/vmmc.c

   1 /*
   2  *  This program is free software; you can redistribute it and/or modify it
   3  *  under the terms of the GNU General Public License version 2 as published
   4  *  by the Free Software Foundation.
   5  *
   6  *  Copyright (C) 2012 John Crispin <john@phrozen.org>
   7  */
   8
   9 #include <linux/export.h>
  10 #include <linux/of_platform.h>
  11 #include <linux/of_gpio.h>
  12 #include <linux/dma-mapping.h>
  13
  14 #include <lantiq_soc.h>
  15
  16 static unsigned int *cp1_base;
  17
  18 unsigned int *ltq_get_cp1_base(void)
  19 {
  20         if (!cp1_base)
  21                 panic("no cp1 base was set\n");
  22
  23         return cp1_base;
  24 }
  25 EXPORT_SYMBOL(ltq_get_cp1_base);
  26
  27 static int vmmc_probe(struct platform_device *pdev)
  28 {
  29 #define CP1_SIZE       (1 << 20)
  30         int gpio_count;
  31         dma_addr_t dma;
  32
  33         cp1_base =
  34                 (void *) CPHYSADDR(dma_alloc_coherent(NULL, CP1_SIZE,
  35                                                     &dma, GFP_ATOMIC));
  36
  37         gpio_count = of_gpio_count(pdev->dev.of_node);
  38         while (gpio_count > 0) {
  39                 enum of_gpio_flags flags;
  40                 int gpio = of_get_gpio_flags(pdev->dev.of_node,
  41                                              --gpio_count, &flags);
  42                 if (gpio_request(gpio, "vmmc-relay"))
  43                         continue;
  44                 dev_info(&pdev->dev, "requested GPIO %d\n", gpio);
  45                 gpio_direction_output(gpio,
  46                                       (flags & OF_GPIO_ACTIVE_LOW) ? (0) : (1));
  47         }
  48
  49         dev_info(&pdev->dev, "reserved %dMB at 0x%p", CP1_SIZE >> 20, cp1_base);
  50
  51         return 0;
  52 }
  53
  54 static const struct of_device_id vmmc_match[] = {
  55         { .compatible = "lantiq,vmmc-xway" },
  56         {},
  57 };
  58
  59 static struct platform_driver vmmc_driver = {
  60         .probe = vmmc_probe,
  61         .driver = {
  62                 .name = "lantiq,vmmc",
  63                 .of_match_table = vmmc_match,
  64         },
  65 };
  66 builtin_platform_driver(vmmc_driver);