drivers/ata/pata_rb532_cf.c

   1 /*
   2  *  A low-level PATA driver to handle a Compact Flash connected on the
   3  *  Mikrotik's RouterBoard 532 board.
   4  *
   5  *  Copyright (C) 2007 Gabor Juhos <juhosg at openwrt.org>
   6  *  Copyright (C) 2008 Florian Fainelli <florian@openwrt.org>
   7  *
   8  *  This file was based on: drivers/ata/pata_ixp4xx_cf.c
   9  *      Copyright (C) 2006-07 Tower Technologies
  10  *      Author: Alessandro Zummo <a.zummo@towertech.it>
  11  *
  12  *  Also was based on the driver for Linux 2.4.xx published by Mikrotik for
  13  *  their RouterBoard 1xx and 5xx series devices. The original Mikrotik code
  14  *  seems not to have a license.
  15  *
  16  *  This program is free software; you can redistribute it and/or modify
  17  *  it under the terms of the GNU General Public License version 2 as
  18  *  published by the Free Software Foundation.
  19  *
  20  */
  21
  22 #include <linux/gfp.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/platform_device.h>
  26
  27 #include <linux/io.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/irq.h>
  30 #include <linux/gpio.h>
  31
  32 #include <linux/libata.h>
  33 #include <scsi/scsi_host.h>
  34
  35 #define DRV_NAME        "pata-rb532-cf"
  36 #define DRV_VERSION     "0.1.0"
  37 #define DRV_DESC        "PATA driver for RouterBOARD 532 Compact Flash"
  38
  39 #define RB500_CF_MAXPORTS       1
  40 #define RB500_CF_IO_DELAY       400
  41
  42 #define RB500_CF_REG_BASE       0x0800
  43 #define RB500_CF_REG_ERR        0x080D
  44 #define RB500_CF_REG_CTRL       0x080E
  45 /* 32bit buffered data register offset */
  46 #define RB500_CF_REG_DBUF32     0x0C00
  47
  48 struct rb532_cf_info {
  49         void __iomem    *iobase;
  50         unsigned int    gpio_line;
  51         unsigned int    irq;
  52 };
  53
  54 /* ------------------------------------------------------------------------ */
  55
  56 static irqreturn_t rb532_pata_irq_handler(int irq, void *dev_instance)
  57 {
  58         struct ata_host *ah = dev_instance;
  59         struct rb532_cf_info *info = ah->private_data;
  60
  61         if (gpio_get_value(info->gpio_line)) {
  62                 irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
  63                 ata_sff_interrupt(info->irq, dev_instance);
  64         } else {
  65                 irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
  66         }
  67
  68         return IRQ_HANDLED;
  69 }
  70
  71 static struct ata_port_operations rb532_pata_port_ops = {
  72         .inherits               = &ata_sff_port_ops,
  73         .sff_data_xfer          = ata_sff_data_xfer32,
  74 };
  75
  76 /* ------------------------------------------------------------------------ */
  77
  78 static struct scsi_host_template rb532_pata_sht = {
  79         ATA_PIO_SHT(DRV_NAME),
  80 };
  81
  82 /* ------------------------------------------------------------------------ */
  83
  84 static void rb532_pata_setup_ports(struct ata_host *ah)
  85 {
  86         struct rb532_cf_info *info = ah->private_data;
  87         struct ata_port *ap;
  88
  89         ap = ah->ports[0];
  90
  91         ap->ops         = &rb532_pata_port_ops;
  92         ap->pio_mask    = ATA_PIO4;
  93
  94         ap->ioaddr.cmd_addr     = info->iobase + RB500_CF_REG_BASE;
  95         ap->ioaddr.ctl_addr     = info->iobase + RB500_CF_REG_CTRL;
  96         ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
  97
  98         ata_sff_std_ports(&ap->ioaddr);
  99
 100         ap->ioaddr.data_addr    = info->iobase + RB500_CF_REG_DBUF32;
 101         ap->ioaddr.error_addr   = info->iobase + RB500_CF_REG_ERR;
 102 }
 103
 104 static int rb532_pata_driver_probe(struct platform_device *pdev)
 105 {
 106         int irq;
 107         int gpio;
 108         struct resource *res;
 109         struct ata_host *ah;
 110         struct rb532_cf_info *info;
 111         int ret;
 112
 113         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 114         if (!res) {
 115                 dev_err(&pdev->dev, "no IOMEM resource found\n");
 116                 return -EINVAL;
 117         }
 118
 119         irq = platform_get_irq(pdev, 0);
 120         if (irq <= 0) {
 121                 dev_err(&pdev->dev, "no IRQ resource found\n");
 122                 return -ENOENT;
 123         }
 124
 125         gpio = irq_to_gpio(irq);
 126         if (gpio < 0) {
 127                 dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
 128                 return -ENOENT;
 129         }
 130
 131         ret = gpio_request(gpio, DRV_NAME);
 132         if (ret) {
 133                 dev_err(&pdev->dev, "GPIO request failed\n");
 134                 return ret;
 135         }
 136
 137         /* allocate host */
 138         ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
 139         if (!ah)
 140                 return -ENOMEM;
 141
 142         platform_set_drvdata(pdev, ah);
 143
 144         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 145         if (!info)
 146                 return -ENOMEM;
 147
 148         ah->private_data = info;
 149         info->gpio_line = gpio;
 150         info->irq = irq;
 151
 152         info->iobase = devm_ioremap_nocache(&pdev->dev, res->start,
 153                                 resource_size(res));
 154         if (!info->iobase)
 155                 return -ENOMEM;
 156
 157         ret = gpio_direction_input(gpio);
 158         if (ret) {
 159                 dev_err(&pdev->dev, "unable to set GPIO direction, err=%d\n",
 160                                 ret);
 161                 goto err_free_gpio;
 162         }
 163
 164         rb532_pata_setup_ports(ah);
 165
 166         ret = ata_host_activate(ah, irq, rb532_pata_irq_handler,
 167                                 IRQF_TRIGGER_LOW, &rb532_pata_sht);
 168         if (ret)
 169                 goto err_free_gpio;
 170
 171         return 0;
 172
 173 err_free_gpio:
 174         gpio_free(gpio);
 175
 176         return ret;
 177 }
 178
 179 static int rb532_pata_driver_remove(struct platform_device *pdev)
 180 {
 181         struct ata_host *ah = platform_get_drvdata(pdev);
 182         struct rb532_cf_info *info = ah->private_data;
 183
 184         ata_host_detach(ah);
 185         gpio_free(info->gpio_line);
 186
 187         return 0;
 188 }
 189
 190 static struct platform_driver rb532_pata_platform_driver = {
 191         .probe          = rb532_pata_driver_probe,
 192         .remove         = rb532_pata_driver_remove,
 193         .driver  = {
 194                 .name   = DRV_NAME,
 195         },
 196 };
 197
 198 #define DRV_INFO DRV_DESC " version " DRV_VERSION
 199
 200 module_platform_driver(rb532_pata_platform_driver);
 201
 202 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 203 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 204 MODULE_DESCRIPTION(DRV_DESC);
 205 MODULE_VERSION(DRV_VERSION);
 206 MODULE_LICENSE("GPL");
 207 MODULE_ALIAS("platform:" DRV_NAME);