root/drivers/video/fbdev/pxa3xx-gcu.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. gc_readl
  2. gc_writel
  3. pxa3xx_gcu_reset
  4. dump_whole_state
  5. flush_running
  6. run_ready
  7. pxa3xx_gcu_handle_irq
  8. pxa3xx_gcu_wait_idle
  9. pxa3xx_gcu_wait_free
  10. to_pxa3xx_gcu_priv
  11. pxa3xx_gcu_open
  12. pxa3xx_gcu_write
  13. pxa3xx_gcu_ioctl
  14. pxa3xx_gcu_mmap
  15. pxa3xx_gcu_debug_timedout
  16. pxa3xx_gcu_init_debug_timer
  17. pxa3xx_gcu_init_debug_timer
  18. pxa3xx_gcu_add_buffer
  19. pxa3xx_gcu_free_buffers
  20. pxa3xx_gcu_probe
  21. pxa3xx_gcu_remove

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  pxa3xx-gcu.c - Linux kernel module for PXA3xx graphics controllers
   4  *
   5  *  This driver needs a DirectFB counterpart in user space, communication
   6  *  is handled via mmap()ed memory areas and an ioctl.
   7  *
   8  *  Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
   9  *  Copyright (c) 2009 Janine Kropp <nin@directfb.org>
  10  *  Copyright (c) 2009 Denis Oliver Kropp <dok@directfb.org>
  11  */
  12 
  13 /*
  14  * WARNING: This controller is attached to System Bus 2 of the PXA which
  15  * needs its arbiter to be enabled explicitly (CKENB & 1<<9).
  16  * There is currently no way to do this from Linux, so you need to teach
  17  * your bootloader for now.
  18  */
  19 
  20 #include <linux/module.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/dma-mapping.h>
  23 #include <linux/miscdevice.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/ioctl.h>
  28 #include <linux/delay.h>
  29 #include <linux/sched.h>
  30 #include <linux/slab.h>
  31 #include <linux/clk.h>
  32 #include <linux/fs.h>
  33 #include <linux/io.h>
  34 #include <linux/of.h>
  35 
  36 #include "pxa3xx-gcu.h"
  37 
  38 #define DRV_NAME        "pxa3xx-gcu"
  39 #define MISCDEV_MINOR   197
  40 
  41 #define REG_GCCR        0x00
  42 #define GCCR_SYNC_CLR   (1 << 9)
  43 #define GCCR_BP_RST     (1 << 8)
  44 #define GCCR_ABORT      (1 << 6)
  45 #define GCCR_STOP       (1 << 4)
  46 
  47 #define REG_GCISCR      0x04
  48 #define REG_GCIECR      0x08
  49 #define REG_GCRBBR      0x20
  50 #define REG_GCRBLR      0x24
  51 #define REG_GCRBHR      0x28
  52 #define REG_GCRBTR      0x2C
  53 #define REG_GCRBEXHR    0x30
  54 
  55 #define IE_EOB          (1 << 0)
  56 #define IE_EEOB         (1 << 5)
  57 #define IE_ALL          0xff
  58 
  59 #define SHARED_SIZE     PAGE_ALIGN(sizeof(struct pxa3xx_gcu_shared))
  60 
  61 /* #define PXA3XX_GCU_DEBUG */
  62 /* #define PXA3XX_GCU_DEBUG_TIMER */
  63 
  64 #ifdef PXA3XX_GCU_DEBUG
  65 #define QDUMP(msg)                                      \
  66         do {                                            \
  67                 QPRINT(priv, KERN_DEBUG, msg);          \
  68         } while (0)
  69 #else
  70 #define QDUMP(msg)      do {} while (0)
  71 #endif
  72 
  73 #define QERROR(msg)                                     \
  74         do {                                            \
  75                 QPRINT(priv, KERN_ERR, msg);            \
  76         } while (0)
  77 
  78 struct pxa3xx_gcu_batch {
  79         struct pxa3xx_gcu_batch *next;
  80         u32                     *ptr;
  81         dma_addr_t               phys;
  82         unsigned long            length;
  83 };
  84 
  85 struct pxa3xx_gcu_priv {
  86         struct device            *dev;
  87         void __iomem             *mmio_base;
  88         struct clk               *clk;
  89         struct pxa3xx_gcu_shared *shared;
  90         dma_addr_t                shared_phys;
  91         struct resource          *resource_mem;
  92         struct miscdevice         misc_dev;
  93         wait_queue_head_t         wait_idle;
  94         wait_queue_head_t         wait_free;
  95         spinlock_t                spinlock;
  96         struct timespec64         base_time;
  97 
  98         struct pxa3xx_gcu_batch *free;
  99         struct pxa3xx_gcu_batch *ready;
 100         struct pxa3xx_gcu_batch *ready_last;
 101         struct pxa3xx_gcu_batch *running;
 102 };
 103 
 104 static inline unsigned long
 105 gc_readl(struct pxa3xx_gcu_priv *priv, unsigned int off)
 106 {
 107         return __raw_readl(priv->mmio_base + off);
 108 }
 109 
 110 static inline void
 111 gc_writel(struct pxa3xx_gcu_priv *priv, unsigned int off, unsigned long val)
 112 {
 113         __raw_writel(val, priv->mmio_base + off);
 114 }
 115 
 116 #define QPRINT(priv, level, msg)                                        \
 117         do {                                                            \
 118                 struct timespec64 ts;                                   \
 119                 struct pxa3xx_gcu_shared *shared = priv->shared;        \
 120                 u32 base = gc_readl(priv, REG_GCRBBR);                  \
 121                                                                         \
 122                 ktime_get_ts64(&ts);                                    \
 123                 ts = timespec64_sub(ts, priv->base_time);               \
 124                                                                         \
 125                 printk(level "%lld.%03ld.%03ld - %-17s: %-21s (%s, "    \
 126                         "STATUS "                                       \
 127                         "0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, "    \
 128                         "T %5ld)\n",                                    \
 129                         (s64)(ts.tv_sec),                               \
 130                         ts.tv_nsec / NSEC_PER_MSEC,                     \
 131                         (ts.tv_nsec % NSEC_PER_MSEC) / USEC_PER_MSEC,   \
 132                         __func__, msg,                                  \
 133                         shared->hw_running ? "running" : "   idle",     \
 134                         gc_readl(priv, REG_GCISCR),                     \
 135                         gc_readl(priv, REG_GCRBBR),                     \
 136                         gc_readl(priv, REG_GCRBLR),                     \
 137                         (gc_readl(priv, REG_GCRBEXHR) - base) / 4,      \
 138                         (gc_readl(priv, REG_GCRBHR) - base) / 4,        \
 139                         (gc_readl(priv, REG_GCRBTR) - base) / 4);       \
 140         } while (0)
 141 
 142 static void
 143 pxa3xx_gcu_reset(struct pxa3xx_gcu_priv *priv)
 144 {
 145         QDUMP("RESET");
 146 
 147         /* disable interrupts */
 148         gc_writel(priv, REG_GCIECR, 0);
 149 
 150         /* reset hardware */
 151         gc_writel(priv, REG_GCCR, GCCR_ABORT);
 152         gc_writel(priv, REG_GCCR, 0);
 153 
 154         memset(priv->shared, 0, SHARED_SIZE);
 155         priv->shared->buffer_phys = priv->shared_phys;
 156         priv->shared->magic = PXA3XX_GCU_SHARED_MAGIC;
 157 
 158         ktime_get_ts64(&priv->base_time);
 159 
 160         /* set up the ring buffer pointers */
 161         gc_writel(priv, REG_GCRBLR, 0);
 162         gc_writel(priv, REG_GCRBBR, priv->shared_phys);
 163         gc_writel(priv, REG_GCRBTR, priv->shared_phys);
 164 
 165         /* enable all IRQs except EOB */
 166         gc_writel(priv, REG_GCIECR, IE_ALL & ~IE_EOB);
 167 }
 168 
 169 static void
 170 dump_whole_state(struct pxa3xx_gcu_priv *priv)
 171 {
 172         struct pxa3xx_gcu_shared *sh = priv->shared;
 173         u32 base = gc_readl(priv, REG_GCRBBR);
 174 
 175         QDUMP("DUMP");
 176 
 177         printk(KERN_DEBUG "== PXA3XX-GCU DUMP ==\n"
 178                 "%s, STATUS 0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, T %5ld\n",
 179                 sh->hw_running ? "running" : "idle   ",
 180                 gc_readl(priv, REG_GCISCR),
 181                 gc_readl(priv, REG_GCRBBR),
 182                 gc_readl(priv, REG_GCRBLR),
 183                 (gc_readl(priv, REG_GCRBEXHR) - base) / 4,
 184                 (gc_readl(priv, REG_GCRBHR) - base) / 4,
 185                 (gc_readl(priv, REG_GCRBTR) - base) / 4);
 186 }
 187 
 188 static void
 189 flush_running(struct pxa3xx_gcu_priv *priv)
 190 {
 191         struct pxa3xx_gcu_batch *running = priv->running;
 192         struct pxa3xx_gcu_batch *next;
 193 
 194         while (running) {
 195                 next = running->next;
 196                 running->next = priv->free;
 197                 priv->free = running;
 198                 running = next;
 199         }
 200 
 201         priv->running = NULL;
 202 }
 203 
 204 static void
 205 run_ready(struct pxa3xx_gcu_priv *priv)
 206 {
 207         unsigned int num = 0;
 208         struct pxa3xx_gcu_shared *shared = priv->shared;
 209         struct pxa3xx_gcu_batch *ready = priv->ready;
 210 
 211         QDUMP("Start");
 212 
 213         BUG_ON(!ready);
 214 
 215         shared->buffer[num++] = 0x05000000;
 216 
 217         while (ready) {
 218                 shared->buffer[num++] = 0x00000001;
 219                 shared->buffer[num++] = ready->phys;
 220                 ready = ready->next;
 221         }
 222 
 223         shared->buffer[num++] = 0x05000000;
 224         priv->running = priv->ready;
 225         priv->ready = priv->ready_last = NULL;
 226         gc_writel(priv, REG_GCRBLR, 0);
 227         shared->hw_running = 1;
 228 
 229         /* ring base address */
 230         gc_writel(priv, REG_GCRBBR, shared->buffer_phys);
 231 
 232         /* ring tail address */
 233         gc_writel(priv, REG_GCRBTR, shared->buffer_phys + num * 4);
 234 
 235         /* ring length */
 236         gc_writel(priv, REG_GCRBLR, ((num + 63) & ~63) * 4);
 237 }
 238 
 239 static irqreturn_t
 240 pxa3xx_gcu_handle_irq(int irq, void *ctx)
 241 {
 242         struct pxa3xx_gcu_priv *priv = ctx;
 243         struct pxa3xx_gcu_shared *shared = priv->shared;
 244         u32 status = gc_readl(priv, REG_GCISCR) & IE_ALL;
 245 
 246         QDUMP("-Interrupt");
 247 
 248         if (!status)
 249                 return IRQ_NONE;
 250 
 251         spin_lock(&priv->spinlock);
 252         shared->num_interrupts++;
 253 
 254         if (status & IE_EEOB) {
 255                 QDUMP(" [EEOB]");
 256 
 257                 flush_running(priv);
 258                 wake_up_all(&priv->wait_free);
 259 
 260                 if (priv->ready) {
 261                         run_ready(priv);
 262                 } else {
 263                         /* There is no more data prepared by the userspace.
 264                          * Set hw_running = 0 and wait for the next userspace
 265                          * kick-off */
 266                         shared->num_idle++;
 267                         shared->hw_running = 0;
 268 
 269                         QDUMP(" '-> Idle.");
 270 
 271                         /* set ring buffer length to zero */
 272                         gc_writel(priv, REG_GCRBLR, 0);
 273 
 274                         wake_up_all(&priv->wait_idle);
 275                 }
 276 
 277                 shared->num_done++;
 278         } else {
 279                 QERROR(" [???]");
 280                 dump_whole_state(priv);
 281         }
 282 
 283         /* Clear the interrupt */
 284         gc_writel(priv, REG_GCISCR, status);
 285         spin_unlock(&priv->spinlock);
 286 
 287         return IRQ_HANDLED;
 288 }
 289 
 290 static int
 291 pxa3xx_gcu_wait_idle(struct pxa3xx_gcu_priv *priv)
 292 {
 293         int ret = 0;
 294 
 295         QDUMP("Waiting for idle...");
 296 
 297         /* Does not need to be atomic. There's a lock in user space,
 298          * but anyhow, this is just for statistics. */
 299         priv->shared->num_wait_idle++;
 300 
 301         while (priv->shared->hw_running) {
 302                 int num = priv->shared->num_interrupts;
 303                 u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
 304 
 305                 ret = wait_event_interruptible_timeout(priv->wait_idle,
 306                                         !priv->shared->hw_running, HZ*4);
 307 
 308                 if (ret != 0)
 309                         break;
 310 
 311                 if (gc_readl(priv, REG_GCRBEXHR) == rbexhr &&
 312                     priv->shared->num_interrupts == num) {
 313                         QERROR("TIMEOUT");
 314                         ret = -ETIMEDOUT;
 315                         break;
 316                 }
 317         }
 318 
 319         QDUMP("done");
 320 
 321         return ret;
 322 }
 323 
 324 static int
 325 pxa3xx_gcu_wait_free(struct pxa3xx_gcu_priv *priv)
 326 {
 327         int ret = 0;
 328 
 329         QDUMP("Waiting for free...");
 330 
 331         /* Does not need to be atomic. There's a lock in user space,
 332          * but anyhow, this is just for statistics. */
 333         priv->shared->num_wait_free++;
 334 
 335         while (!priv->free) {
 336                 u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
 337 
 338                 ret = wait_event_interruptible_timeout(priv->wait_free,
 339                                                        priv->free, HZ*4);
 340 
 341                 if (ret < 0)
 342                         break;
 343 
 344                 if (ret > 0)
 345                         continue;
 346 
 347                 if (gc_readl(priv, REG_GCRBEXHR) == rbexhr) {
 348                         QERROR("TIMEOUT");
 349                         ret = -ETIMEDOUT;
 350                         break;
 351                 }
 352         }
 353 
 354         QDUMP("done");
 355 
 356         return ret;
 357 }
 358 
 359 /* Misc device layer */
 360 
 361 static inline struct pxa3xx_gcu_priv *to_pxa3xx_gcu_priv(struct file *file)
 362 {
 363         struct miscdevice *dev = file->private_data;
 364         return container_of(dev, struct pxa3xx_gcu_priv, misc_dev);
 365 }
 366 
 367 /*
 368  * provide an empty .open callback, so the core sets file->private_data
 369  * for us.
 370  */
 371 static int pxa3xx_gcu_open(struct inode *inode, struct file *file)
 372 {
 373         return 0;
 374 }
 375 
 376 static ssize_t
 377 pxa3xx_gcu_write(struct file *file, const char *buff,
 378                  size_t count, loff_t *offp)
 379 {
 380         int ret;
 381         unsigned long flags;
 382         struct pxa3xx_gcu_batch *buffer;
 383         struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file);
 384 
 385         int words = count / 4;
 386 
 387         /* Does not need to be atomic. There's a lock in user space,
 388          * but anyhow, this is just for statistics. */
 389         priv->shared->num_writes++;
 390         priv->shared->num_words += words;
 391 
 392         /* Last word reserved for batch buffer end command */
 393         if (words >= PXA3XX_GCU_BATCH_WORDS)
 394                 return -E2BIG;
 395 
 396         /* Wait for a free buffer */
 397         if (!priv->free) {
 398                 ret = pxa3xx_gcu_wait_free(priv);
 399                 if (ret < 0)
 400                         return ret;
 401         }
 402 
 403         /*
 404          * Get buffer from free list
 405          */
 406         spin_lock_irqsave(&priv->spinlock, flags);
 407         buffer = priv->free;
 408         priv->free = buffer->next;
 409         spin_unlock_irqrestore(&priv->spinlock, flags);
 410 
 411 
 412         /* Copy data from user into buffer */
 413         ret = copy_from_user(buffer->ptr, buff, words * 4);
 414         if (ret) {
 415                 spin_lock_irqsave(&priv->spinlock, flags);
 416                 buffer->next = priv->free;
 417                 priv->free = buffer;
 418                 spin_unlock_irqrestore(&priv->spinlock, flags);
 419                 return -EFAULT;
 420         }
 421 
 422         buffer->length = words;
 423 
 424         /* Append batch buffer end command */
 425         buffer->ptr[words] = 0x01000000;
 426 
 427         /*
 428          * Add buffer to ready list
 429          */
 430         spin_lock_irqsave(&priv->spinlock, flags);
 431 
 432         buffer->next = NULL;
 433 
 434         if (priv->ready) {
 435                 BUG_ON(priv->ready_last == NULL);
 436 
 437                 priv->ready_last->next = buffer;
 438         } else
 439                 priv->ready = buffer;
 440 
 441         priv->ready_last = buffer;
 442 
 443         if (!priv->shared->hw_running)
 444                 run_ready(priv);
 445 
 446         spin_unlock_irqrestore(&priv->spinlock, flags);
 447 
 448         return words * 4;
 449 }
 450 
 451 
 452 static long
 453 pxa3xx_gcu_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 454 {
 455         unsigned long flags;
 456         struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file);
 457 
 458         switch (cmd) {
 459         case PXA3XX_GCU_IOCTL_RESET:
 460                 spin_lock_irqsave(&priv->spinlock, flags);
 461                 pxa3xx_gcu_reset(priv);
 462                 spin_unlock_irqrestore(&priv->spinlock, flags);
 463                 return 0;
 464 
 465         case PXA3XX_GCU_IOCTL_WAIT_IDLE:
 466                 return pxa3xx_gcu_wait_idle(priv);
 467         }
 468 
 469         return -ENOSYS;
 470 }
 471 
 472 static int
 473 pxa3xx_gcu_mmap(struct file *file, struct vm_area_struct *vma)
 474 {
 475         unsigned int size = vma->vm_end - vma->vm_start;
 476         struct pxa3xx_gcu_priv *priv = to_pxa3xx_gcu_priv(file);
 477 
 478         switch (vma->vm_pgoff) {
 479         case 0:
 480                 /* hand out the shared data area */
 481                 if (size != SHARED_SIZE)
 482                         return -EINVAL;
 483 
 484                 return dma_mmap_coherent(priv->dev, vma,
 485                         priv->shared, priv->shared_phys, size);
 486 
 487         case SHARED_SIZE >> PAGE_SHIFT:
 488                 /* hand out the MMIO base for direct register access
 489                  * from userspace */
 490                 if (size != resource_size(priv->resource_mem))
 491                         return -EINVAL;
 492 
 493                 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 494 
 495                 return io_remap_pfn_range(vma, vma->vm_start,
 496                                 priv->resource_mem->start >> PAGE_SHIFT,
 497                                 size, vma->vm_page_prot);
 498         }
 499 
 500         return -EINVAL;
 501 }
 502 
 503 
 504 #ifdef PXA3XX_GCU_DEBUG_TIMER
 505 static struct timer_list pxa3xx_gcu_debug_timer;
 506 static struct pxa3xx_gcu_priv *debug_timer_priv;
 507 
 508 static void pxa3xx_gcu_debug_timedout(struct timer_list *unused)
 509 {
 510         struct pxa3xx_gcu_priv *priv = debug_timer_priv;
 511 
 512         QERROR("Timer DUMP");
 513 
 514         mod_timer(&pxa3xx_gcu_debug_timer, jiffies + 5 * HZ);
 515 }
 516 
 517 static void pxa3xx_gcu_init_debug_timer(struct pxa3xx_gcu_priv *priv)
 518 {
 519         /* init the timer structure */
 520         debug_timer_priv = priv;
 521         timer_setup(&pxa3xx_gcu_debug_timer, pxa3xx_gcu_debug_timedout, 0);
 522         pxa3xx_gcu_debug_timedout(NULL);
 523 }
 524 #else
 525 static inline void pxa3xx_gcu_init_debug_timer(struct pxa3xx_gcu_priv *priv) {}
 526 #endif
 527 
 528 static int
 529 pxa3xx_gcu_add_buffer(struct device *dev,
 530                       struct pxa3xx_gcu_priv *priv)
 531 {
 532         struct pxa3xx_gcu_batch *buffer;
 533 
 534         buffer = kzalloc(sizeof(struct pxa3xx_gcu_batch), GFP_KERNEL);
 535         if (!buffer)
 536                 return -ENOMEM;
 537 
 538         buffer->ptr = dma_alloc_coherent(dev, PXA3XX_GCU_BATCH_WORDS * 4,
 539                                          &buffer->phys, GFP_KERNEL);
 540         if (!buffer->ptr) {
 541                 kfree(buffer);
 542                 return -ENOMEM;
 543         }
 544 
 545         buffer->next = priv->free;
 546         priv->free = buffer;
 547 
 548         return 0;
 549 }
 550 
 551 static void
 552 pxa3xx_gcu_free_buffers(struct device *dev,
 553                         struct pxa3xx_gcu_priv *priv)
 554 {
 555         struct pxa3xx_gcu_batch *next, *buffer = priv->free;
 556 
 557         while (buffer) {
 558                 next = buffer->next;
 559 
 560                 dma_free_coherent(dev, PXA3XX_GCU_BATCH_WORDS * 4,
 561                                   buffer->ptr, buffer->phys);
 562 
 563                 kfree(buffer);
 564                 buffer = next;
 565         }
 566 
 567         priv->free = NULL;
 568 }
 569 
 570 static const struct file_operations pxa3xx_gcu_miscdev_fops = {
 571         .owner =                THIS_MODULE,
 572         .open =                 pxa3xx_gcu_open,
 573         .write =                pxa3xx_gcu_write,
 574         .unlocked_ioctl =       pxa3xx_gcu_ioctl,
 575         .mmap =                 pxa3xx_gcu_mmap,
 576 };
 577 
 578 static int pxa3xx_gcu_probe(struct platform_device *pdev)
 579 {
 580         int i, ret, irq;
 581         struct resource *r;
 582         struct pxa3xx_gcu_priv *priv;
 583         struct device *dev = &pdev->dev;
 584 
 585         priv = devm_kzalloc(dev, sizeof(struct pxa3xx_gcu_priv), GFP_KERNEL);
 586         if (!priv)
 587                 return -ENOMEM;
 588 
 589         init_waitqueue_head(&priv->wait_idle);
 590         init_waitqueue_head(&priv->wait_free);
 591         spin_lock_init(&priv->spinlock);
 592 
 593         /* we allocate the misc device structure as part of our own allocation,
 594          * so we can get a pointer to our priv structure later on with
 595          * container_of(). This isn't really necessary as we have a fixed minor
 596          * number anyway, but this is to avoid statics. */
 597 
 598         priv->misc_dev.minor    = MISCDEV_MINOR,
 599         priv->misc_dev.name     = DRV_NAME,
 600         priv->misc_dev.fops     = &pxa3xx_gcu_miscdev_fops;
 601 
 602         /* handle IO resources */
 603         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 604         priv->mmio_base = devm_ioremap_resource(dev, r);
 605         if (IS_ERR(priv->mmio_base))
 606                 return PTR_ERR(priv->mmio_base);
 607 
 608         /* enable the clock */
 609         priv->clk = devm_clk_get(dev, NULL);
 610         if (IS_ERR(priv->clk)) {
 611                 dev_err(dev, "failed to get clock\n");
 612                 return PTR_ERR(priv->clk);
 613         }
 614 
 615         /* request the IRQ */
 616         irq = platform_get_irq(pdev, 0);
 617         if (irq < 0) {
 618                 dev_err(dev, "no IRQ defined: %d\n", irq);
 619                 return irq;
 620         }
 621 
 622         ret = devm_request_irq(dev, irq, pxa3xx_gcu_handle_irq,
 623                                0, DRV_NAME, priv);
 624         if (ret < 0) {
 625                 dev_err(dev, "request_irq failed\n");
 626                 return ret;
 627         }
 628 
 629         /* allocate dma memory */
 630         priv->shared = dma_alloc_coherent(dev, SHARED_SIZE,
 631                                           &priv->shared_phys, GFP_KERNEL);
 632         if (!priv->shared) {
 633                 dev_err(dev, "failed to allocate DMA memory\n");
 634                 return -ENOMEM;
 635         }
 636 
 637         /* register misc device */
 638         ret = misc_register(&priv->misc_dev);
 639         if (ret < 0) {
 640                 dev_err(dev, "misc_register() for minor %d failed\n",
 641                         MISCDEV_MINOR);
 642                 goto err_free_dma;
 643         }
 644 
 645         ret = clk_prepare_enable(priv->clk);
 646         if (ret < 0) {
 647                 dev_err(dev, "failed to enable clock\n");
 648                 goto err_misc_deregister;
 649         }
 650 
 651         for (i = 0; i < 8; i++) {
 652                 ret = pxa3xx_gcu_add_buffer(dev, priv);
 653                 if (ret) {
 654                         dev_err(dev, "failed to allocate DMA memory\n");
 655                         goto err_disable_clk;
 656                 }
 657         }
 658 
 659         platform_set_drvdata(pdev, priv);
 660         priv->resource_mem = r;
 661         priv->dev = dev;
 662         pxa3xx_gcu_reset(priv);
 663         pxa3xx_gcu_init_debug_timer(priv);
 664 
 665         dev_info(dev, "registered @0x%p, DMA 0x%p (%d bytes), IRQ %d\n",
 666                         (void *) r->start, (void *) priv->shared_phys,
 667                         SHARED_SIZE, irq);
 668         return 0;
 669 
 670 err_free_dma:
 671         dma_free_coherent(dev, SHARED_SIZE,
 672                         priv->shared, priv->shared_phys);
 673 
 674 err_misc_deregister:
 675         misc_deregister(&priv->misc_dev);
 676 
 677 err_disable_clk:
 678         clk_disable_unprepare(priv->clk);
 679 
 680         return ret;
 681 }
 682 
 683 static int pxa3xx_gcu_remove(struct platform_device *pdev)
 684 {
 685         struct pxa3xx_gcu_priv *priv = platform_get_drvdata(pdev);
 686         struct device *dev = &pdev->dev;
 687 
 688         pxa3xx_gcu_wait_idle(priv);
 689         misc_deregister(&priv->misc_dev);
 690         dma_free_coherent(dev, SHARED_SIZE, priv->shared, priv->shared_phys);
 691         pxa3xx_gcu_free_buffers(dev, priv);
 692 
 693         return 0;
 694 }
 695 
 696 #ifdef CONFIG_OF
 697 static const struct of_device_id pxa3xx_gcu_of_match[] = {
 698         { .compatible = "marvell,pxa300-gcu", },
 699         { }
 700 };
 701 MODULE_DEVICE_TABLE(of, pxa3xx_gcu_of_match);
 702 #endif
 703 
 704 static struct platform_driver pxa3xx_gcu_driver = {
 705         .probe    = pxa3xx_gcu_probe,
 706         .remove  = pxa3xx_gcu_remove,
 707         .driver  = {
 708                 .name   = DRV_NAME,
 709                 .of_match_table = of_match_ptr(pxa3xx_gcu_of_match),
 710         },
 711 };
 712 
 713 module_platform_driver(pxa3xx_gcu_driver);
 714 
 715 MODULE_DESCRIPTION("PXA3xx graphics controller unit driver");
 716 MODULE_LICENSE("GPL");
 717 MODULE_ALIAS_MISCDEV(MISCDEV_MINOR);
 718 MODULE_AUTHOR("Janine Kropp <nin@directfb.org>, "
 719                 "Denis Oliver Kropp <dok@directfb.org>, "
 720                 "Daniel Mack <daniel@caiaq.de>");

/* [<][>][^][v][top][bottom][index][help] */