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
  31 #include <linux/libata.h>
  32 #include <scsi/scsi_host.h>
  33
  34 #include <asm/gpio.h>
  35
  36 #define DRV_NAME        "pata-rb532-cf"
  37 #define DRV_VERSION     "0.1.0"
  38 #define DRV_DESC        "PATA driver for RouterBOARD 532 Compact Flash"
  39
  40 #define RB500_CF_MAXPORTS       1
  41 #define RB500_CF_IO_DELAY       400
  42
  43 #define RB500_CF_REG_BASE       0x0800
  44 #define RB500_CF_REG_ERR        0x080D
  45 #define RB500_CF_REG_CTRL       0x080E
  46 /* 32bit buffered data register offset */
  47 #define RB500_CF_REG_DBUF32     0x0C00
  48
  49 struct rb532_cf_info {
  50         void __iomem    *iobase;
  51         unsigned int    gpio_line;
  52         unsigned int    irq;
  53 };
  54
  55 /* ------------------------------------------------------------------------ */
  56
  57 static irqreturn_t rb532_pata_irq_handler(int irq, void *dev_instance)
  58 {
  59         struct ata_host *ah = dev_instance;
  60         struct rb532_cf_info *info = ah->private_data;
  61
  62         if (gpio_get_value(info->gpio_line)) {
  63                 irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
  64                 ata_sff_interrupt(info->irq, dev_instance);
  65         } else {
  66                 irq_set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
  67         }
  68
  69         return IRQ_HANDLED;
  70 }
  71
  72 static struct ata_port_operations rb532_pata_port_ops = {
  73         .inherits               = &ata_sff_port_ops,
  74         .sff_data_xfer          = ata_sff_data_xfer32,
  75 };
  76
  77 /* ------------------------------------------------------------------------ */
  78
  79 static struct scsi_host_template rb532_pata_sht = {
  80         ATA_PIO_SHT(DRV_NAME),
  81 };
  82
  83 /* ------------------------------------------------------------------------ */
  84
  85 static void rb532_pata_setup_ports(struct ata_host *ah)
  86 {
  87         struct rb532_cf_info *info = ah->private_data;
  88         struct ata_port *ap;
  89
  90         ap = ah->ports[0];
  91
  92         ap->ops         = &rb532_pata_port_ops;
  93         ap->pio_mask    = ATA_PIO4;
  94
  95         ap->ioaddr.cmd_addr     = info->iobase + RB500_CF_REG_BASE;
  96         ap->ioaddr.ctl_addr     = info->iobase + RB500_CF_REG_CTRL;
  97         ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
  98
  99         ata_sff_std_ports(&ap->ioaddr);
 100
 101         ap->ioaddr.data_addr    = info->iobase + RB500_CF_REG_DBUF32;
 102         ap->ioaddr.error_addr   = info->iobase + RB500_CF_REG_ERR;
 103 }
 104
 105 static int rb532_pata_driver_probe(struct platform_device *pdev)
 106 {
 107         int irq;
 108         int gpio;
 109         struct resource *res;
 110         struct ata_host *ah;
 111         struct rb532_cf_info *info;
 112         int ret;
 113
 114         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 115         if (!res) {
 116                 dev_err(&pdev->dev, "no IOMEM resource found\n");
 117                 return -EINVAL;
 118         }
 119
 120         irq = platform_get_irq(pdev, 0);
 121         if (irq <= 0) {
 122                 dev_err(&pdev->dev, "no IRQ resource found\n");
 123                 return -ENOENT;
 124         }
 125
 126         gpio = irq_to_gpio(irq);
 127         if (gpio < 0) {
 128                 dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
 129                 return -ENOENT;
 130         }
 131
 132         ret = gpio_request(gpio, DRV_NAME);
 133         if (ret) {
 134                 dev_err(&pdev->dev, "GPIO request failed\n");
 135                 return ret;
 136         }
 137
 138         /* allocate host */
 139         ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
 140         if (!ah)
 141                 return -ENOMEM;
 142
 143         platform_set_drvdata(pdev, ah);
 144
 145         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 146         if (!info)
 147                 return -ENOMEM;
 148
 149         ah->private_data = info;
 150         info->gpio_line = gpio;
 151         info->irq = irq;
 152
 153         info->iobase = devm_ioremap_nocache(&pdev->dev, res->start,
 154                                 resource_size(res));
 155         if (!info->iobase)
 156                 return -ENOMEM;
 157
 158         ret = gpio_direction_input(gpio);
 159         if (ret) {
 160                 dev_err(&pdev->dev, "unable to set GPIO direction, err=%d\n",
 161                                 ret);
 162                 goto err_free_gpio;
 163         }
 164
 165         rb532_pata_setup_ports(ah);
 166
 167         ret = ata_host_activate(ah, irq, rb532_pata_irq_handler,
 168                                 IRQF_TRIGGER_LOW, &rb532_pata_sht);
 169         if (ret)
 170                 goto err_free_gpio;
 171
 172         return 0;
 173
 174 err_free_gpio:
 175         gpio_free(gpio);
 176
 177         return ret;
 178 }
 179
 180 static int rb532_pata_driver_remove(struct platform_device *pdev)
 181 {
 182         struct ata_host *ah = platform_get_drvdata(pdev);
 183         struct rb532_cf_info *info = ah->private_data;
 184
 185         ata_host_detach(ah);
 186         gpio_free(info->gpio_line);
 187
 188         return 0;
 189 }
 190
 191 static struct platform_driver rb532_pata_platform_driver = {
 192         .probe          = rb532_pata_driver_probe,
 193         .remove         = rb532_pata_driver_remove,
 194         .driver  = {
 195                 .name   = DRV_NAME,
 196         },
 197 };
 198
 199 #define DRV_INFO DRV_DESC " version " DRV_VERSION
 200
 201 module_platform_driver(rb532_pata_platform_driver);
 202
 203 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 204 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 205 MODULE_DESCRIPTION(DRV_DESC);
 206 MODULE_VERSION(DRV_VERSION);
 207 MODULE_LICENSE("GPL");
 208 MODULE_ALIAS("platform:" DRV_NAME);