drivers/gpio/bt8xxgpio.c

   1 /*
   2
   3     bt8xx GPIO abuser
   4
   5     Copyright (C) 2008 Michael Buesch <m@bues.ch>
   6
   7     Please do _only_ contact the people listed _above_ with issues related to this driver.
   8     All the other people listed below are not related to this driver. Their names
   9     are only here, because this driver is derived from the bt848 driver.
  10
  11
  12     Derived from the bt848 driver:
  13
  14     Copyright (C) 1996,97,98 Ralph  Metzler
  15                            & Marcus Metzler
  16     (c) 1999-2002 Gerd Knorr
  17
  18     some v4l2 code lines are taken from Justin's bttv2 driver which is
  19     (c) 2000 Justin Schoeman
  20
  21     V4L1 removal from:
  22     (c) 2005-2006 Nickolay V. Shmyrev
  23
  24     Fixes to be fully V4L2 compliant by
  25     (c) 2006 Mauro Carvalho Chehab
  26
  27     Cropping and overscan support
  28     Copyright (C) 2005, 2006 Michael H. Schimek
  29     Sponsored by OPQ Systems AB
  30
  31     This program is free software; you can redistribute it and/or modify
  32     it under the terms of the GNU General Public License as published by
  33     the Free Software Foundation; either version 2 of the License, or
  34     (at your option) any later version.
  35
  36     This program is distributed in the hope that it will be useful,
  37     but WITHOUT ANY WARRANTY; without even the implied warranty of
  38     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  39     GNU General Public License for more details.
  40
  41     You should have received a copy of the GNU General Public License
  42     along with this program; if not, write to the Free Software
  43     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  44 */
  45
  46 #include <linux/module.h>
  47 #include <linux/pci.h>
  48 #include <linux/spinlock.h>
  49 #include <linux/gpio.h>
  50 #include <linux/slab.h>
  51
  52 /* Steal the hardware definitions from the bttv driver. */
  53 #include "../media/video/bt8xx/bt848.h"
  54
  55
  56 #define BT8XXGPIO_NR_GPIOS              24 /* We have 24 GPIO pins */
  57
  58
  59 struct bt8xxgpio {
  60         spinlock_t lock;
  61
  62         void __iomem *mmio;
  63         struct pci_dev *pdev;
  64         struct gpio_chip gpio;
  65
  66 #ifdef CONFIG_PM
  67         u32 saved_outen;
  68         u32 saved_data;
  69 #endif
  70 };
  71
  72 #define bgwrite(dat, adr)       writel((dat), bg->mmio+(adr))
  73 #define bgread(adr)             readl(bg->mmio+(adr))
  74
  75
  76 static int modparam_gpiobase = -1/* dynamic */;
  77 module_param_named(gpiobase, modparam_gpiobase, int, 0444);
  78 MODULE_PARM_DESC(gpiobase, "The GPIO number base. -1 means dynamic, which is the default.");
  79
  80
  81 static int bt8xxgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
  82 {
  83         struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
  84         unsigned long flags;
  85         u32 outen, data;
  86
  87         spin_lock_irqsave(&bg->lock, flags);
  88
  89         data = bgread(BT848_GPIO_DATA);
  90         data &= ~(1 << nr);
  91         bgwrite(data, BT848_GPIO_DATA);
  92
  93         outen = bgread(BT848_GPIO_OUT_EN);
  94         outen &= ~(1 << nr);
  95         bgwrite(outen, BT848_GPIO_OUT_EN);
  96
  97         spin_unlock_irqrestore(&bg->lock, flags);
  98
  99         return 0;
 100 }
 101
 102 static int bt8xxgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
 103 {
 104         struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
 105         unsigned long flags;
 106         u32 val;
 107
 108         spin_lock_irqsave(&bg->lock, flags);
 109         val = bgread(BT848_GPIO_DATA);
 110         spin_unlock_irqrestore(&bg->lock, flags);
 111
 112         return !!(val & (1 << nr));
 113 }
 114
 115 static int bt8xxgpio_gpio_direction_output(struct gpio_chip *gpio,
 116                                         unsigned nr, int val)
 117 {
 118         struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
 119         unsigned long flags;
 120         u32 outen, data;
 121
 122         spin_lock_irqsave(&bg->lock, flags);
 123
 124         outen = bgread(BT848_GPIO_OUT_EN);
 125         outen |= (1 << nr);
 126         bgwrite(outen, BT848_GPIO_OUT_EN);
 127
 128         data = bgread(BT848_GPIO_DATA);
 129         if (val)
 130                 data |= (1 << nr);
 131         else
 132                 data &= ~(1 << nr);
 133         bgwrite(data, BT848_GPIO_DATA);
 134
 135         spin_unlock_irqrestore(&bg->lock, flags);
 136
 137         return 0;
 138 }
 139
 140 static void bt8xxgpio_gpio_set(struct gpio_chip *gpio,
 141                             unsigned nr, int val)
 142 {
 143         struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
 144         unsigned long flags;
 145         u32 data;
 146
 147         spin_lock_irqsave(&bg->lock, flags);
 148
 149         data = bgread(BT848_GPIO_DATA);
 150         if (val)
 151                 data |= (1 << nr);
 152         else
 153                 data &= ~(1 << nr);
 154         bgwrite(data, BT848_GPIO_DATA);
 155
 156         spin_unlock_irqrestore(&bg->lock, flags);
 157 }
 158
 159 static void bt8xxgpio_gpio_setup(struct bt8xxgpio *bg)
 160 {
 161         struct gpio_chip *c = &bg->gpio;
 162
 163         c->label = dev_name(&bg->pdev->dev);
 164         c->owner = THIS_MODULE;
 165         c->direction_input = bt8xxgpio_gpio_direction_input;
 166         c->get = bt8xxgpio_gpio_get;
 167         c->direction_output = bt8xxgpio_gpio_direction_output;
 168         c->set = bt8xxgpio_gpio_set;
 169         c->dbg_show = NULL;
 170         c->base = modparam_gpiobase;
 171         c->ngpio = BT8XXGPIO_NR_GPIOS;
 172         c->can_sleep = 0;
 173 }
 174
 175 static int bt8xxgpio_probe(struct pci_dev *dev,
 176                         const struct pci_device_id *pci_id)
 177 {
 178         struct bt8xxgpio *bg;
 179         int err;
 180
 181         bg = kzalloc(sizeof(*bg), GFP_KERNEL);
 182         if (!bg)
 183                 return -ENOMEM;
 184
 185         bg->pdev = dev;
 186         spin_lock_init(&bg->lock);
 187
 188         err = pci_enable_device(dev);
 189         if (err) {
 190                 printk(KERN_ERR "bt8xxgpio: Can't enable device.\n");
 191                 goto err_freebg;
 192         }
 193         if (!request_mem_region(pci_resource_start(dev, 0),
 194                                 pci_resource_len(dev, 0),
 195                                 "bt8xxgpio")) {
 196                 printk(KERN_WARNING "bt8xxgpio: Can't request iomem (0x%llx).\n",
 197                        (unsigned long long)pci_resource_start(dev, 0));
 198                 err = -EBUSY;
 199                 goto err_disable;
 200         }
 201         pci_set_master(dev);
 202         pci_set_drvdata(dev, bg);
 203
 204         bg->mmio = ioremap(pci_resource_start(dev, 0), 0x1000);
 205         if (!bg->mmio) {
 206                 printk(KERN_ERR "bt8xxgpio: ioremap() failed\n");
 207                 err = -EIO;
 208                 goto err_release_mem;
 209         }
 210
 211         /* Disable interrupts */
 212         bgwrite(0, BT848_INT_MASK);
 213
 214         /* gpio init */
 215         bgwrite(0, BT848_GPIO_DMA_CTL);
 216         bgwrite(0, BT848_GPIO_REG_INP);
 217         bgwrite(0, BT848_GPIO_OUT_EN);
 218
 219         bt8xxgpio_gpio_setup(bg);
 220         err = gpiochip_add(&bg->gpio);
 221         if (err) {
 222                 printk(KERN_ERR "bt8xxgpio: Failed to register GPIOs\n");
 223                 goto err_release_mem;
 224         }
 225
 226         printk(KERN_INFO "bt8xxgpio: Abusing BT8xx card for GPIOs %d to %d\n",
 227                bg->gpio.base, bg->gpio.base + BT8XXGPIO_NR_GPIOS - 1);
 228
 229         return 0;
 230
 231 err_release_mem:
 232         release_mem_region(pci_resource_start(dev, 0),
 233                            pci_resource_len(dev, 0));
 234         pci_set_drvdata(dev, NULL);
 235 err_disable:
 236         pci_disable_device(dev);
 237 err_freebg:
 238         kfree(bg);
 239
 240         return err;
 241 }
 242
 243 static void bt8xxgpio_remove(struct pci_dev *pdev)
 244 {
 245         struct bt8xxgpio *bg = pci_get_drvdata(pdev);
 246
 247         gpiochip_remove(&bg->gpio);
 248
 249         bgwrite(0, BT848_INT_MASK);
 250         bgwrite(~0x0, BT848_INT_STAT);
 251         bgwrite(0x0, BT848_GPIO_OUT_EN);
 252
 253         iounmap(bg->mmio);
 254         release_mem_region(pci_resource_start(pdev, 0),
 255                            pci_resource_len(pdev, 0));
 256         pci_disable_device(pdev);
 257
 258         pci_set_drvdata(pdev, NULL);
 259         kfree(bg);
 260 }
 261
 262 #ifdef CONFIG_PM
 263 static int bt8xxgpio_suspend(struct pci_dev *pdev, pm_message_t state)
 264 {
 265         struct bt8xxgpio *bg = pci_get_drvdata(pdev);
 266         unsigned long flags;
 267
 268         spin_lock_irqsave(&bg->lock, flags);
 269
 270         bg->saved_outen = bgread(BT848_GPIO_OUT_EN);
 271         bg->saved_data = bgread(BT848_GPIO_DATA);
 272
 273         bgwrite(0, BT848_INT_MASK);
 274         bgwrite(~0x0, BT848_INT_STAT);
 275         bgwrite(0x0, BT848_GPIO_OUT_EN);
 276
 277         spin_unlock_irqrestore(&bg->lock, flags);
 278
 279         pci_save_state(pdev);
 280         pci_disable_device(pdev);
 281         pci_set_power_state(pdev, pci_choose_state(pdev, state));
 282
 283         return 0;
 284 }
 285
 286 static int bt8xxgpio_resume(struct pci_dev *pdev)
 287 {
 288         struct bt8xxgpio *bg = pci_get_drvdata(pdev);
 289         unsigned long flags;
 290         int err;
 291
 292         pci_set_power_state(pdev, 0);
 293         err = pci_enable_device(pdev);
 294         if (err)
 295                 return err;
 296         pci_restore_state(pdev);
 297
 298         spin_lock_irqsave(&bg->lock, flags);
 299
 300         bgwrite(0, BT848_INT_MASK);
 301         bgwrite(0, BT848_GPIO_DMA_CTL);
 302         bgwrite(0, BT848_GPIO_REG_INP);
 303         bgwrite(bg->saved_outen, BT848_GPIO_OUT_EN);
 304         bgwrite(bg->saved_data & bg->saved_outen,
 305                 BT848_GPIO_DATA);
 306
 307         spin_unlock_irqrestore(&bg->lock, flags);
 308
 309         return 0;
 310 }
 311 #else
 312 #define bt8xxgpio_suspend NULL
 313 #define bt8xxgpio_resume NULL
 314 #endif /* CONFIG_PM */
 315
 316 static struct pci_device_id bt8xxgpio_pci_tbl[] = {
 317         { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT848) },
 318         { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT849) },
 319         { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT878) },
 320         { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT879) },
 321         { 0, },
 322 };
 323 MODULE_DEVICE_TABLE(pci, bt8xxgpio_pci_tbl);
 324
 325 static struct pci_driver bt8xxgpio_pci_driver = {
 326         .name           = "bt8xxgpio",
 327         .id_table       = bt8xxgpio_pci_tbl,
 328         .probe          = bt8xxgpio_probe,
 329         .remove         = bt8xxgpio_remove,
 330         .suspend        = bt8xxgpio_suspend,
 331         .resume         = bt8xxgpio_resume,
 332 };
 333
 334 static int __init bt8xxgpio_init(void)
 335 {
 336         return pci_register_driver(&bt8xxgpio_pci_driver);
 337 }
 338 module_init(bt8xxgpio_init)
 339
 340 static void __exit bt8xxgpio_exit(void)
 341 {
 342         pci_unregister_driver(&bt8xxgpio_pci_driver);
 343 }
 344 module_exit(bt8xxgpio_exit)
 345
 346 MODULE_LICENSE("GPL");
 347 MODULE_AUTHOR("Michael Buesch");
 348 MODULE_DESCRIPTION("Abuse a BT8xx framegrabber card as generic GPIO card");