drivers/media/video/marvell-ccic/cafe-driver.c

   1 /*
   2  * A driver for the CMOS camera controller in the Marvell 88ALP01 "cafe"
   3  * multifunction chip.  Currently works with the Omnivision OV7670
   4  * sensor.
   5  *
   6  * The data sheet for this device can be found at:
   7  *    http://www.marvell.com/products/pc_connectivity/88alp01/
   8  *
   9  * Copyright 2006-11 One Laptop Per Child Association, Inc.
  10  * Copyright 2006-11 Jonathan Corbet <corbet@lwn.net>
  11  *
  12  * Written by Jonathan Corbet, corbet@lwn.net.
  13  *
  14  * v4l2_device/v4l2_subdev conversion by:
  15  * Copyright (C) 2009 Hans Verkuil <hverkuil@xs4all.nl>
  16  *
  17  * Note: this conversion is untested! Please contact the linux-media
  18  * mailinglist if you can test this, together with the test results.
  19  *
  20  * This file may be distributed under the terms of the GNU General
  21  * Public License, version 2.
  22  */
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/init.h>
  26 #include <linux/pci.h>
  27 #include <linux/i2c.h>
  28 #include <linux/interrupt.h>
  29 #include <linux/spinlock.h>
  30 #include <linux/slab.h>
  31 #include <linux/videodev2.h>
  32 #include <media/v4l2-device.h>
  33 #include <media/v4l2-chip-ident.h>
  34 #include <linux/device.h>
  35 #include <linux/wait.h>
  36 #include <linux/delay.h>
  37 #include <linux/io.h>
  38
  39 #include "mcam-core.h"
  40
  41 #define CAFE_VERSION 0x000002
  42
  43
  44 /*
  45  * Parameters.
  46  */
  47 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
  48 MODULE_DESCRIPTION("Marvell 88ALP01 CMOS Camera Controller driver");
  49 MODULE_LICENSE("GPL");
  50 MODULE_SUPPORTED_DEVICE("Video");
  51
  52
  53
  54
  55 struct cafe_camera {
  56         int registered;                 /* Fully initialized? */
  57         struct mcam_camera mcam;
  58         struct pci_dev *pdev;
  59         wait_queue_head_t smbus_wait;   /* Waiting on i2c events */
  60 };
  61
  62 /*
  63  * Debugging and related.
  64  */
  65 #define cam_err(cam, fmt, arg...) \
  66         dev_err(&(cam)->pdev->dev, fmt, ##arg);
  67 #define cam_warn(cam, fmt, arg...) \
  68         dev_warn(&(cam)->pdev->dev, fmt, ##arg);
  69
  70 /* -------------------------------------------------------------------- */
  71 /*
  72  * The I2C/SMBUS interface to the camera itself starts here.  The
  73  * controller handles SMBUS itself, presenting a relatively simple register
  74  * interface; all we have to do is to tell it where to route the data.
  75  */
  76 #define CAFE_SMBUS_TIMEOUT (HZ)  /* generous */
  77
  78 static inline struct cafe_camera *to_cam(struct v4l2_device *dev)
  79 {
  80         struct mcam_camera *m = container_of(dev, struct mcam_camera, v4l2_dev);
  81         return container_of(m, struct cafe_camera, mcam);
  82 }
  83
  84
  85 static int cafe_smbus_write_done(struct mcam_camera *mcam)
  86 {
  87         unsigned long flags;
  88         int c1;
  89
  90         /*
  91          * We must delay after the interrupt, or the controller gets confused
  92          * and never does give us good status.  Fortunately, we don't do this
  93          * often.
  94          */
  95         udelay(20);
  96         spin_lock_irqsave(&mcam->dev_lock, flags);
  97         c1 = mcam_reg_read(mcam, REG_TWSIC1);
  98         spin_unlock_irqrestore(&mcam->dev_lock, flags);
  99         return (c1 & (TWSIC1_WSTAT|TWSIC1_ERROR)) != TWSIC1_WSTAT;
 100 }
 101
 102 static int cafe_smbus_write_data(struct cafe_camera *cam,
 103                 u16 addr, u8 command, u8 value)
 104 {
 105         unsigned int rval;
 106         unsigned long flags;
 107         struct mcam_camera *mcam = &cam->mcam;
 108
 109         spin_lock_irqsave(&mcam->dev_lock, flags);
 110         rval = TWSIC0_EN | ((addr << TWSIC0_SID_SHIFT) & TWSIC0_SID);
 111         rval |= TWSIC0_OVMAGIC;  /* Make OV sensors work */
 112         /*
 113          * Marvell sez set clkdiv to all 1's for now.
 114          */
 115         rval |= TWSIC0_CLKDIV;
 116         mcam_reg_write(mcam, REG_TWSIC0, rval);
 117         (void) mcam_reg_read(mcam, REG_TWSIC1); /* force write */
 118         rval = value | ((command << TWSIC1_ADDR_SHIFT) & TWSIC1_ADDR);
 119         mcam_reg_write(mcam, REG_TWSIC1, rval);
 120         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 121
 122         /* Unfortunately, reading TWSIC1 too soon after sending a command
 123          * causes the device to die.
 124          * Use a busy-wait because we often send a large quantity of small
 125          * commands at-once; using msleep() would cause a lot of context
 126          * switches which take longer than 2ms, resulting in a noticeable
 127          * boot-time and capture-start delays.
 128          */
 129         mdelay(2);
 130
 131         /*
 132          * Another sad fact is that sometimes, commands silently complete but
 133          * cafe_smbus_write_done() never becomes aware of this.
 134          * This happens at random and appears to possible occur with any
 135          * command.
 136          * We don't understand why this is. We work around this issue
 137          * with the timeout in the wait below, assuming that all commands
 138          * complete within the timeout.
 139          */
 140         wait_event_timeout(cam->smbus_wait, cafe_smbus_write_done(mcam),
 141                         CAFE_SMBUS_TIMEOUT);
 142
 143         spin_lock_irqsave(&mcam->dev_lock, flags);
 144         rval = mcam_reg_read(mcam, REG_TWSIC1);
 145         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 146
 147         if (rval & TWSIC1_WSTAT) {
 148                 cam_err(cam, "SMBUS write (%02x/%02x/%02x) timed out\n", addr,
 149                                 command, value);
 150                 return -EIO;
 151         }
 152         if (rval & TWSIC1_ERROR) {
 153                 cam_err(cam, "SMBUS write (%02x/%02x/%02x) error\n", addr,
 154                                 command, value);
 155                 return -EIO;
 156         }
 157         return 0;
 158 }
 159
 160
 161
 162 static int cafe_smbus_read_done(struct mcam_camera *mcam)
 163 {
 164         unsigned long flags;
 165         int c1;
 166
 167         /*
 168          * We must delay after the interrupt, or the controller gets confused
 169          * and never does give us good status.  Fortunately, we don't do this
 170          * often.
 171          */
 172         udelay(20);
 173         spin_lock_irqsave(&mcam->dev_lock, flags);
 174         c1 = mcam_reg_read(mcam, REG_TWSIC1);
 175         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 176         return c1 & (TWSIC1_RVALID|TWSIC1_ERROR);
 177 }
 178
 179
 180
 181 static int cafe_smbus_read_data(struct cafe_camera *cam,
 182                 u16 addr, u8 command, u8 *value)
 183 {
 184         unsigned int rval;
 185         unsigned long flags;
 186         struct mcam_camera *mcam = &cam->mcam;
 187
 188         spin_lock_irqsave(&mcam->dev_lock, flags);
 189         rval = TWSIC0_EN | ((addr << TWSIC0_SID_SHIFT) & TWSIC0_SID);
 190         rval |= TWSIC0_OVMAGIC; /* Make OV sensors work */
 191         /*
 192          * Marvel sez set clkdiv to all 1's for now.
 193          */
 194         rval |= TWSIC0_CLKDIV;
 195         mcam_reg_write(mcam, REG_TWSIC0, rval);
 196         (void) mcam_reg_read(mcam, REG_TWSIC1); /* force write */
 197         rval = TWSIC1_READ | ((command << TWSIC1_ADDR_SHIFT) & TWSIC1_ADDR);
 198         mcam_reg_write(mcam, REG_TWSIC1, rval);
 199         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 200
 201         wait_event_timeout(cam->smbus_wait,
 202                         cafe_smbus_read_done(mcam), CAFE_SMBUS_TIMEOUT);
 203         spin_lock_irqsave(&mcam->dev_lock, flags);
 204         rval = mcam_reg_read(mcam, REG_TWSIC1);
 205         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 206
 207         if (rval & TWSIC1_ERROR) {
 208                 cam_err(cam, "SMBUS read (%02x/%02x) error\n", addr, command);
 209                 return -EIO;
 210         }
 211         if (!(rval & TWSIC1_RVALID)) {
 212                 cam_err(cam, "SMBUS read (%02x/%02x) timed out\n", addr,
 213                                 command);
 214                 return -EIO;
 215         }
 216         *value = rval & 0xff;
 217         return 0;
 218 }
 219
 220 /*
 221  * Perform a transfer over SMBUS.  This thing is called under
 222  * the i2c bus lock, so we shouldn't race with ourselves...
 223  */
 224 static int cafe_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
 225                 unsigned short flags, char rw, u8 command,
 226                 int size, union i2c_smbus_data *data)
 227 {
 228         struct cafe_camera *cam = i2c_get_adapdata(adapter);
 229         int ret = -EINVAL;
 230
 231         /*
 232          * This interface would appear to only do byte data ops.  OK
 233          * it can do word too, but the cam chip has no use for that.
 234          */
 235         if (size != I2C_SMBUS_BYTE_DATA) {
 236                 cam_err(cam, "funky xfer size %d\n", size);
 237                 return -EINVAL;
 238         }
 239
 240         if (rw == I2C_SMBUS_WRITE)
 241                 ret = cafe_smbus_write_data(cam, addr, command, data->byte);
 242         else if (rw == I2C_SMBUS_READ)
 243                 ret = cafe_smbus_read_data(cam, addr, command, &data->byte);
 244         return ret;
 245 }
 246
 247
 248 static void cafe_smbus_enable_irq(struct cafe_camera *cam)
 249 {
 250         unsigned long flags;
 251
 252         spin_lock_irqsave(&cam->mcam.dev_lock, flags);
 253         mcam_reg_set_bit(&cam->mcam, REG_IRQMASK, TWSIIRQS);
 254         spin_unlock_irqrestore(&cam->mcam.dev_lock, flags);
 255 }
 256
 257 static u32 cafe_smbus_func(struct i2c_adapter *adapter)
 258 {
 259         return I2C_FUNC_SMBUS_READ_BYTE_DATA  |
 260                I2C_FUNC_SMBUS_WRITE_BYTE_DATA;
 261 }
 262
 263 static struct i2c_algorithm cafe_smbus_algo = {
 264         .smbus_xfer = cafe_smbus_xfer,
 265         .functionality = cafe_smbus_func
 266 };
 267
 268 static int cafe_smbus_setup(struct cafe_camera *cam)
 269 {
 270         struct i2c_adapter *adap = &cam->mcam.i2c_adapter;
 271         int ret;
 272
 273         cafe_smbus_enable_irq(cam);
 274         adap->owner = THIS_MODULE;
 275         adap->algo = &cafe_smbus_algo;
 276         strcpy(adap->name, "cafe_ccic");
 277         adap->dev.parent = &cam->pdev->dev;
 278         i2c_set_adapdata(adap, cam);
 279         ret = i2c_add_adapter(adap);
 280         if (ret)
 281                 printk(KERN_ERR "Unable to register cafe i2c adapter\n");
 282         return ret;
 283 }
 284
 285 static void cafe_smbus_shutdown(struct cafe_camera *cam)
 286 {
 287         i2c_del_adapter(&cam->mcam.i2c_adapter);
 288 }
 289
 290
 291 /*
 292  * Controller-level stuff
 293  */
 294
 295 static void cafe_ctlr_init(struct mcam_camera *mcam)
 296 {
 297         unsigned long flags;
 298
 299         spin_lock_irqsave(&mcam->dev_lock, flags);
 300         /*
 301          * Added magic to bring up the hardware on the B-Test board
 302          */
 303         mcam_reg_write(mcam, 0x3038, 0x8);
 304         mcam_reg_write(mcam, 0x315c, 0x80008);
 305         /*
 306          * Go through the dance needed to wake the device up.
 307          * Note that these registers are global and shared
 308          * with the NAND and SD devices.  Interaction between the
 309          * three still needs to be examined.
 310          */
 311         mcam_reg_write(mcam, REG_GL_CSR, GCSR_SRS|GCSR_MRS); /* Needed? */
 312         mcam_reg_write(mcam, REG_GL_CSR, GCSR_SRC|GCSR_MRC);
 313         mcam_reg_write(mcam, REG_GL_CSR, GCSR_SRC|GCSR_MRS);
 314         /*
 315          * Here we must wait a bit for the controller to come around.
 316          */
 317         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 318         msleep(5);
 319         spin_lock_irqsave(&mcam->dev_lock, flags);
 320
 321         mcam_reg_write(mcam, REG_GL_CSR, GCSR_CCIC_EN|GCSR_SRC|GCSR_MRC);
 322         mcam_reg_set_bit(mcam, REG_GL_IMASK, GIMSK_CCIC_EN);
 323         /*
 324          * Mask all interrupts.
 325          */
 326         mcam_reg_write(mcam, REG_IRQMASK, 0);
 327         spin_unlock_irqrestore(&mcam->dev_lock, flags);
 328 }
 329
 330
 331 static void cafe_ctlr_power_up(struct mcam_camera *mcam)
 332 {
 333         /*
 334          * Part one of the sensor dance: turn the global
 335          * GPIO signal on.
 336          */
 337         mcam_reg_write(mcam, REG_GL_FCR, GFCR_GPIO_ON);
 338         mcam_reg_write(mcam, REG_GL_GPIOR, GGPIO_OUT|GGPIO_VAL);
 339         /*
 340          * Put the sensor into operational mode (assumes OLPC-style
 341          * wiring).  Control 0 is reset - set to 1 to operate.
 342          * Control 1 is power down, set to 0 to operate.
 343          */
 344         mcam_reg_write(mcam, REG_GPR, GPR_C1EN|GPR_C0EN); /* pwr up, reset */
 345         mcam_reg_write(mcam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C0);
 346 }
 347
 348 static void cafe_ctlr_power_down(struct mcam_camera *mcam)
 349 {
 350         mcam_reg_write(mcam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C1);
 351         mcam_reg_write(mcam, REG_GL_FCR, GFCR_GPIO_ON);
 352         mcam_reg_write(mcam, REG_GL_GPIOR, GGPIO_OUT);
 353 }
 354
 355
 356
 357 /*
 358  * The platform interrupt handler.
 359  */
 360 static irqreturn_t cafe_irq(int irq, void *data)
 361 {
 362         struct cafe_camera *cam = data;
 363         struct mcam_camera *mcam = &cam->mcam;
 364         unsigned int irqs, handled;
 365
 366         spin_lock(&mcam->dev_lock);
 367         irqs = mcam_reg_read(mcam, REG_IRQSTAT);
 368         handled = cam->registered && mccic_irq(mcam, irqs);
 369         if (irqs & TWSIIRQS) {
 370                 mcam_reg_write(mcam, REG_IRQSTAT, TWSIIRQS);
 371                 wake_up(&cam->smbus_wait);
 372                 handled = 1;
 373         }
 374         spin_unlock(&mcam->dev_lock);
 375         return IRQ_RETVAL(handled);
 376 }
 377
 378
 379 /* -------------------------------------------------------------------------- */
 380 /*
 381  * PCI interface stuff.
 382  */
 383
 384 static int cafe_pci_probe(struct pci_dev *pdev,
 385                 const struct pci_device_id *id)
 386 {
 387         int ret;
 388         struct cafe_camera *cam;
 389         struct mcam_camera *mcam;
 390
 391         /*
 392          * Start putting together one of our big camera structures.
 393          */
 394         ret = -ENOMEM;
 395         cam = kzalloc(sizeof(struct cafe_camera), GFP_KERNEL);
 396         if (cam == NULL)
 397                 goto out;
 398         cam->pdev = pdev;
 399         mcam = &cam->mcam;
 400         mcam->chip_id = V4L2_IDENT_CAFE;
 401         spin_lock_init(&mcam->dev_lock);
 402         init_waitqueue_head(&cam->smbus_wait);
 403         mcam->plat_power_up = cafe_ctlr_power_up;
 404         mcam->plat_power_down = cafe_ctlr_power_down;
 405         mcam->dev = &pdev->dev;
 406         /*
 407          * Get set up on the PCI bus.
 408          */
 409         ret = pci_enable_device(pdev);
 410         if (ret)
 411                 goto out_free;
 412         pci_set_master(pdev);
 413
 414         ret = -EIO;
 415         mcam->regs = pci_iomap(pdev, 0, 0);
 416         if (!mcam->regs) {
 417                 printk(KERN_ERR "Unable to ioremap cafe-ccic regs\n");
 418                 goto out_disable;
 419         }
 420         ret = request_irq(pdev->irq, cafe_irq, IRQF_SHARED, "cafe-ccic", cam);
 421         if (ret)
 422                 goto out_iounmap;
 423
 424         /*
 425          * Initialize the controller and leave it powered up.  It will
 426          * stay that way until the sensor driver shows up.
 427          */
 428         cafe_ctlr_init(mcam);
 429         cafe_ctlr_power_up(mcam);
 430         /*
 431          * Set up I2C/SMBUS communications.  We have to drop the mutex here
 432          * because the sensor could attach in this call chain, leading to
 433          * unsightly deadlocks.
 434          */
 435         ret = cafe_smbus_setup(cam);
 436         if (ret)
 437                 goto out_pdown;
 438
 439         ret = mccic_register(mcam);
 440         if (ret == 0) {
 441                 cam->registered = 1;
 442                 return 0;
 443         }
 444
 445         cafe_smbus_shutdown(cam);
 446 out_pdown:
 447         cafe_ctlr_power_down(mcam);
 448         free_irq(pdev->irq, cam);
 449 out_iounmap:
 450         pci_iounmap(pdev, mcam->regs);
 451 out_disable:
 452         pci_disable_device(pdev);
 453 out_free:
 454         kfree(cam);
 455 out:
 456         return ret;
 457 }
 458
 459
 460 /*
 461  * Shut down an initialized device
 462  */
 463 static void cafe_shutdown(struct cafe_camera *cam)
 464 {
 465         mccic_shutdown(&cam->mcam);
 466         cafe_smbus_shutdown(cam);
 467         free_irq(cam->pdev->irq, cam);
 468         pci_iounmap(cam->pdev, cam->mcam.regs);
 469 }
 470
 471
 472 static void cafe_pci_remove(struct pci_dev *pdev)
 473 {
 474         struct v4l2_device *v4l2_dev = dev_get_drvdata(&pdev->dev);
 475         struct cafe_camera *cam = to_cam(v4l2_dev);
 476
 477         if (cam == NULL) {
 478                 printk(KERN_WARNING "pci_remove on unknown pdev %p\n", pdev);
 479                 return;
 480         }
 481         cafe_shutdown(cam);
 482         kfree(cam);
 483 }
 484
 485
 486 #ifdef CONFIG_PM
 487 /*
 488  * Basic power management.
 489  */
 490 static int cafe_pci_suspend(struct pci_dev *pdev, pm_message_t state)
 491 {
 492         struct v4l2_device *v4l2_dev = dev_get_drvdata(&pdev->dev);
 493         struct cafe_camera *cam = to_cam(v4l2_dev);
 494         int ret;
 495
 496         ret = pci_save_state(pdev);
 497         if (ret)
 498                 return ret;
 499         mccic_suspend(&cam->mcam);
 500         pci_disable_device(pdev);
 501         return 0;
 502 }
 503
 504
 505 static int cafe_pci_resume(struct pci_dev *pdev)
 506 {
 507         struct v4l2_device *v4l2_dev = dev_get_drvdata(&pdev->dev);
 508         struct cafe_camera *cam = to_cam(v4l2_dev);
 509         int ret = 0;
 510
 511         pci_restore_state(pdev);
 512         ret = pci_enable_device(pdev);
 513
 514         if (ret) {
 515                 cam_warn(cam, "Unable to re-enable device on resume!\n");
 516                 return ret;
 517         }
 518         cafe_ctlr_init(&cam->mcam);
 519         return mccic_resume(&cam->mcam);
 520 }
 521
 522 #endif  /* CONFIG_PM */
 523
 524 static struct pci_device_id cafe_ids[] = {
 525         { PCI_DEVICE(PCI_VENDOR_ID_MARVELL,
 526                      PCI_DEVICE_ID_MARVELL_88ALP01_CCIC) },
 527         { 0, }
 528 };
 529
 530 MODULE_DEVICE_TABLE(pci, cafe_ids);
 531
 532 static struct pci_driver cafe_pci_driver = {
 533         .name = "cafe1000-ccic",
 534         .id_table = cafe_ids,
 535         .probe = cafe_pci_probe,
 536         .remove = cafe_pci_remove,
 537 #ifdef CONFIG_PM
 538         .suspend = cafe_pci_suspend,
 539         .resume = cafe_pci_resume,
 540 #endif
 541 };
 542
 543
 544
 545
 546 static int __init cafe_init(void)
 547 {
 548         int ret;
 549
 550         printk(KERN_NOTICE "Marvell M88ALP01 'CAFE' Camera Controller version %d\n",
 551                         CAFE_VERSION);
 552         ret = pci_register_driver(&cafe_pci_driver);
 553         if (ret) {
 554                 printk(KERN_ERR "Unable to register cafe_ccic driver\n");
 555                 goto out;
 556         }
 557         ret = 0;
 558
 559 out:
 560         return ret;
 561 }
 562
 563
 564 static void __exit cafe_exit(void)
 565 {
 566         pci_unregister_driver(&cafe_pci_driver);
 567 }
 568
 569 module_init(cafe_init);
 570 module_exit(cafe_exit);