package/system/wrt55agv2-spidevs/src/wrt55agv2_spidevs.c

   1 /*
   2  * SPI driver for the Linksys WRT55AG v2 board.
   3  *
   4  * Copyright (C) 2008 Gabor Juhos <juhosg at openwrt.org>
   5  *
   6  * This file was based on the mmc_over_gpio driver:
   7  *      Copyright 2008 Michael Buesch <mb@bu3sch.de>
   8  *
   9  * This program is free software; you can redistribute it and/or modify it
  10  * under the terms of the GNU General Public License version 2 as published
  11  * by the Free Software Foundation.
  12  */
  13
  14 #include <linux/platform_device.h>
  15 #include <linux/spi/spi_gpio_old.h>
  16 #include <linux/module.h>
  17
  18 #define DRV_NAME        "wrt55agv2-spidevs"
  19 #define DRV_DESC        "SPI driver for the WRT55AG v2 board"
  20 #define DRV_VERSION     "0.1.0"
  21 #define PFX             DRV_NAME ": "
  22
  23 #define GPIO_PIN_MISO   1
  24 #define GPIO_PIN_CS     2
  25 #define GPIO_PIN_CLK    3
  26 #define GPIO_PIN_MOSI   4
  27
  28 static struct platform_device *spi_gpio_dev;
  29
  30 static int __init boardinfo_setup(struct spi_board_info *bi,
  31                 struct spi_master *master, void *data)
  32 {
  33
  34         strlcpy(bi->modalias, "spi-ks8995", sizeof(bi->modalias));
  35
  36         bi->max_speed_hz = 5000000 /* Hz */;
  37         bi->bus_num = master->bus_num;
  38         bi->mode = SPI_MODE_0;
  39
  40         return 0;
  41 }
  42
  43 static int __init wrt55agv2_spidevs_init(void)
  44 {
  45         struct spi_gpio_platform_data pdata;
  46         int err;
  47
  48         spi_gpio_dev = platform_device_alloc("spi-gpio", 0);
  49         if (!spi_gpio_dev) {
  50                 printk(KERN_ERR PFX "no memory for spi-gpio device\n");
  51                 return -ENOMEM;
  52         }
  53
  54         memset(&pdata, 0, sizeof(pdata));
  55         pdata.pin_miso = GPIO_PIN_MISO;
  56         pdata.pin_cs = GPIO_PIN_CS;
  57         pdata.pin_clk = GPIO_PIN_CLK;
  58         pdata.pin_mosi = GPIO_PIN_MOSI;
  59         pdata.cs_activelow = 1;
  60         pdata.no_spi_delay = 1;
  61         pdata.boardinfo_setup = boardinfo_setup;
  62         pdata.boardinfo_setup_data = NULL;
  63
  64         err = platform_device_add_data(spi_gpio_dev, &pdata, sizeof(pdata));
  65         if (err)
  66                 goto err_free_dev;
  67
  68         err = platform_device_register(spi_gpio_dev);
  69         if (err) {
  70                 printk(KERN_ERR PFX "unable to register device\n");
  71                 goto err_free_pdata;
  72         }
  73
  74         return 0;
  75
  76 err_free_pdata:
  77         kfree(spi_gpio_dev->dev.platform_data);
  78         spi_gpio_dev->dev.platform_data = NULL;
  79
  80 err_free_dev:
  81         platform_device_put(spi_gpio_dev);
  82         return err;
  83 }
  84
  85 static void __exit wrt55agv2_spidevs_cleanup(void)
  86 {
  87         if (!spi_gpio_dev)
  88                 return;
  89
  90         platform_device_unregister(spi_gpio_dev);
  91
  92         kfree(spi_gpio_dev->dev.platform_data);
  93         spi_gpio_dev->dev.platform_data = NULL;
  94         platform_device_put(spi_gpio_dev);
  95 }
  96
  97 static int __init wrt55agv2_spidevs_modinit(void)
  98 {
  99         printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
 100         return wrt55agv2_spidevs_init();
 101 }
 102 module_init(wrt55agv2_spidevs_modinit);
 103
 104 static void __exit wrt55agv2_spidevs_modexit(void)
 105 {
 106         wrt55agv2_spidevs_cleanup();
 107 }
 108 module_exit(wrt55agv2_spidevs_modexit);
 109
 110 MODULE_DESCRIPTION(DRV_DESC);
 111 MODULE_VERSION(DRV_VERSION);
 112 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 113 MODULE_LICENSE("GPL v2");
 114