drivers/ata/pata_rb500_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/kernel.h>
  23 #include <linux/module.h>
  24 #include <linux/platform_device.h>
  25
  26 #include <linux/io.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/irq.h>
  29
  30 #include <linux/libata.h>
  31 #include <scsi/scsi_host.h>
  32
  33 #include <asm/gpio.h>
  34
  35 #define DRV_NAME        "pata-rb500-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_CMD        0x0800
  43 #define RB500_CF_REG_CTRL       0x080E
  44 #define RB500_CF_REG_DATA       0x0C00
  45
  46 struct rb500_cf_info {
  47         void __iomem    *iobase;
  48         unsigned int    gpio_line;
  49         int             frozen;
  50         unsigned int    irq;
  51 };
  52
  53 /* ------------------------------------------------------------------------ */
  54
  55 static inline void rb500_pata_finish_io(struct ata_port *ap)
  56 {
  57         struct ata_host *ah = ap->host;
  58         struct rb500_cf_info *info = ah->private_data;
  59
  60         ata_sff_altstatus(ap);
  61         ndelay(RB500_CF_IO_DELAY);
  62
  63         set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
  64 }
  65
  66 static void rb500_pata_exec_command(struct ata_port *ap,
  67                                 const struct ata_taskfile *tf)
  68 {
  69         writeb(tf->command, ap->ioaddr.command_addr);
  70         rb500_pata_finish_io(ap);
  71 }
  72
  73 static void rb500_pata_data_xfer(struct ata_device *adev, unsigned char *buf,
  74                                 unsigned int buflen, int write_data)
  75 {
  76         struct ata_port *ap = adev->link->ap;
  77         void __iomem *ioaddr = ap->ioaddr.data_addr;
  78
  79         if (write_data) {
  80                 for (; buflen > 0; buflen--, buf++)
  81                         writeb(*buf, ioaddr);
  82         } else {
  83                 for (; buflen > 0; buflen--, buf++)
  84                         *buf = readb(ioaddr);
  85         }
  86
  87         rb500_pata_finish_io(adev->link->ap);
  88 }
  89
  90 static void rb500_pata_freeze(struct ata_port *ap)
  91 {
  92         struct rb500_cf_info *info = ap->host->private_data;
  93
  94         info->frozen = 1;
  95 }
  96
  97 static void rb500_pata_thaw(struct ata_port *ap)
  98 {
  99         struct rb500_cf_info *info = ap->host->private_data;
 100
 101         info->frozen = 0;
 102 }
 103
 104 static irqreturn_t rb500_pata_irq_handler(int irq, void *dev_instance)
 105 {
 106         struct ata_host *ah = dev_instance;
 107         struct rb500_cf_info *info = ah->private_data;
 108
 109         if (gpio_get_value(info->gpio_line)) {
 110                 set_irq_type(info->irq, IRQ_TYPE_LEVEL_LOW);
 111                 if (!info->frozen)
 112                         ata_sff_interrupt(info->irq, dev_instance);
 113         } else {
 114                 set_irq_type(info->irq, IRQ_TYPE_LEVEL_HIGH);
 115         }
 116
 117         return IRQ_HANDLED;
 118 }
 119
 120 static struct ata_port_operations rb500_pata_port_ops = {
 121         .inherits               = &ata_sff_port_ops,
 122         .sff_exec_command       = rb500_pata_exec_command,
 123         .sff_data_xfer          = rb500_pata_data_xfer,
 124         .freeze                 = rb500_pata_freeze,
 125         .thaw                   = rb500_pata_thaw,
 126 };
 127
 128 /* ------------------------------------------------------------------------ */
 129
 130 static struct scsi_host_template rb500_pata_sht = {
 131         ATA_PIO_SHT(DRV_NAME),
 132 };
 133
 134 /* ------------------------------------------------------------------------ */
 135
 136 static void rb500_pata_setup_ports(struct ata_host *ah)
 137 {
 138         struct rb500_cf_info *info = ah->private_data;
 139         struct ata_port *ap;
 140
 141         ap = ah->ports[0];
 142
 143         ap->ops         = &rb500_pata_port_ops;
 144         ap->pio_mask    = 0x1f; /* PIO4 */
 145         ap->flags       = ATA_FLAG_NO_LEGACY | ATA_FLAG_MMIO;
 146
 147         ap->ioaddr.cmd_addr     = info->iobase + RB500_CF_REG_CMD;
 148         ap->ioaddr.ctl_addr     = info->iobase + RB500_CF_REG_CTRL;
 149         ap->ioaddr.altstatus_addr = info->iobase + RB500_CF_REG_CTRL;
 150
 151         ata_sff_std_ports(&ap->ioaddr);
 152
 153         ap->ioaddr.data_addr    = info->iobase + RB500_CF_REG_DATA;
 154 }
 155
 156 static __devinit int rb500_pata_driver_probe(struct platform_device *pdev)
 157 {
 158         unsigned int irq;
 159         int gpio;
 160         struct resource *res;
 161         struct ata_host *ah;
 162         struct rb500_cf_info *info;
 163         int ret;
 164
 165         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 166         if (!res) {
 167                 dev_err(&pdev->dev, "no IOMEM resource found\n");
 168                 return -EINVAL;
 169         }
 170
 171         irq = platform_get_irq(pdev, 0);
 172         if (irq <= 0) {
 173                 dev_err(&pdev->dev, "no IRQ resource found\n");
 174                 return -ENOENT;
 175         }
 176
 177         gpio = irq_to_gpio(irq);
 178         if (gpio < 0) {
 179                 dev_err(&pdev->dev, "no GPIO found for irq%d\n", irq);
 180                 return -ENOENT;
 181         }
 182
 183         ret = gpio_request(gpio, DRV_NAME);
 184         if (ret) {
 185                 dev_err(&pdev->dev, "GPIO request failed\n");
 186                 return ret;
 187         }
 188
 189         /* allocate host */
 190         ah = ata_host_alloc(&pdev->dev, RB500_CF_MAXPORTS);
 191         if (!ah)
 192                 return -ENOMEM;
 193
 194         platform_set_drvdata(pdev, ah);
 195
 196         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 197         if (!info)
 198                 return -ENOMEM;
 199
 200         ah->private_data = info;
 201         info->gpio_line = gpio;
 202         info->irq = irq;
 203
 204         info->iobase = devm_ioremap_nocache(&pdev->dev, res->start,
 205                                 res->end - res->start + 1);
 206         if (!info->iobase)
 207                 return -ENOMEM;
 208
 209         ret = gpio_direction_input(gpio);
 210         if (ret) {
 211                 dev_err(&pdev->dev, "unable to set GPIO direction, err=%d\n",
 212                                 ret);
 213                 goto err_free_gpio;
 214         }
 215
 216         rb500_pata_setup_ports(ah);
 217
 218         ret = ata_host_activate(ah, irq, rb500_pata_irq_handler,
 219                                 IRQF_TRIGGER_LOW, &rb500_pata_sht);
 220         if (ret)
 221                 goto err_free_gpio;
 222
 223         return 0;
 224
 225 err_free_gpio:
 226         gpio_free(gpio);
 227
 228         return ret;
 229 }
 230
 231 static __devexit int rb500_pata_driver_remove(struct platform_device *pdev)
 232 {
 233         struct ata_host *ah = platform_get_drvdata(pdev);
 234         struct rb500_cf_info *info = ah->private_data;
 235
 236         ata_host_detach(ah);
 237         gpio_free(info->gpio_line);
 238
 239         return 0;
 240 }
 241
 242 /* work with hotplug and coldplug */
 243 MODULE_ALIAS("platform:" DRV_NAME);
 244
 245 static struct platform_driver rb500_pata_platform_driver = {
 246         .probe          = rb500_pata_driver_probe,
 247         .remove         = __devexit_p(rb500_pata_driver_remove),
 248         .driver  = {
 249                 .name   = DRV_NAME,
 250                 .owner  = THIS_MODULE,
 251         },
 252 };
 253
 254 /* ------------------------------------------------------------------------ */
 255
 256 #define DRV_INFO DRV_DESC " version " DRV_VERSION
 257
 258 static int __init rb500_pata_module_init(void)
 259 {
 260         printk(KERN_INFO DRV_INFO "\n");
 261
 262         return platform_driver_register(&rb500_pata_platform_driver);
 263 }
 264
 265 static void __exit rb500_pata_module_exit(void)
 266 {
 267         platform_driver_unregister(&rb500_pata_platform_driver);
 268 }
 269
 270 MODULE_AUTHOR("Gabor Juhos <juhosg at openwrt.org>");
 271 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 272 MODULE_DESCRIPTION(DRV_DESC);
 273 MODULE_VERSION(DRV_VERSION);
 274 MODULE_LICENSE("GPL");
 275
 276 module_init(rb500_pata_module_init);
 277 module_exit(rb500_pata_module_exit);