package/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.h>
  16
  17 #define DRV_NAME        "wrt55agv2-spidevs"
  18 #define DRV_DESC        "SPI driver for the WRT55AG v2 board"
  19 #define DRV_VERSION     "0.1.0"
  20 #define PFX             DRV_NAME ": "
  21
  22 #define GPIO_PIN_MISO   1
  23 #define GPIO_PIN_CS     2
  24 #define GPIO_PIN_CLK    3
  25 #define GPIO_PIN_MOSI   4
  26
  27 static struct platform_device *spi_gpio_dev;
  28
  29 static int __init boardinfo_setup(struct spi_board_info *bi,
  30                 struct spi_master *master, void *data)
  31 {
  32
  33         strlcpy(bi->modalias, "spi-ks8995", sizeof(bi->modalias));
  34
  35         bi->max_speed_hz = 5000000 /* Hz */;
  36         bi->bus_num = master->bus_num;
  37         bi->mode = SPI_MODE_0;
  38
  39         return 0;
  40 }
  41
  42 static int __init wrt55agv2_spidevs_init(void)
  43 {
  44         struct spi_gpio_platform_data pdata;
  45         int err;
  46
  47         spi_gpio_dev = platform_device_alloc("spi-gpio", 0);
  48         if (!spi_gpio_dev) {
  49                 printk(KERN_ERR PFX "no memory for spi-gpio device\n");
  50                 return -ENOMEM;
  51         }
  52
  53         memset(&pdata, 0, sizeof(pdata));
  54         pdata.pin_miso = GPIO_PIN_MISO;
  55         pdata.pin_cs = GPIO_PIN_CS;
  56         pdata.pin_clk = GPIO_PIN_CLK;
  57         pdata.pin_mosi = GPIO_PIN_MOSI;
  58         pdata.cs_activelow = 1;
  59         pdata.no_spi_delay = 1;
  60         pdata.boardinfo_setup = boardinfo_setup;
  61         pdata.boardinfo_setup_data = NULL;
  62
  63         err = platform_device_add_data(spi_gpio_dev, &pdata, sizeof(pdata));
  64         if (err)
  65                 goto err_free_dev;
  66
  67         err = platform_device_register(spi_gpio_dev);
  68         if (err) {
  69                 printk(KERN_ERR PFX "unable to register device\n");
  70                 goto err_free_pdata;
  71         }
  72
  73         return 0;
  74
  75 err_free_pdata:
  76         kfree(spi_gpio_dev->dev.platform_data);
  77         spi_gpio_dev->dev.platform_data = NULL;
  78
  79 err_free_dev:
  80         platform_device_put(spi_gpio_dev);
  81         return err;
  82 }
  83
  84 static void __exit wrt55agv2_spidevs_cleanup(void)
  85 {
  86         if (!spi_gpio_dev)
  87                 return;
  88
  89         platform_device_unregister(spi_gpio_dev);
  90
  91         kfree(spi_gpio_dev->dev.platform_data);
  92         spi_gpio_dev->dev.platform_data = NULL;
  93         platform_device_put(spi_gpio_dev);
  94 }
  95
  96 static int __init wrt55agv2_spidevs_modinit(void)
  97 {
  98         printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
  99         return wrt55agv2_spidevs_init();
 100 }
 101 module_init(wrt55agv2_spidevs_modinit);
 102
 103 static void __exit wrt55agv2_spidevs_modexit(void)
 104 {
 105         wrt55agv2_spidevs_cleanup();
 106 }
 107 module_exit(wrt55agv2_spidevs_modexit);
 108
 109 MODULE_DESCRIPTION(DRV_DESC);
 110 MODULE_VERSION(DRV_VERSION);
 111 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 112 MODULE_LICENSE("GPL v2");
 113