1 files changed, 772 insertions, 0 deletions

diff --git a/drivers/video/pxa3xx-gcu.c b/drivers/video/pxa3xx-gcu.c
new file mode 100644
index 000000000000..b81168df253d
--- /dev/null
+++ b/drivers/video/pxa3xx-gcu.c
@@ -0,0 +1,772 @@
+/*
+ *  pxa3xx-gc.c - Linux kernel module for PXA3xx graphics controllers
+ *
+ *  This driver needs a DirectFB counterpart in user space, communication
+ *  is handled via mmap()ed memory areas and an ioctl.
+ *
+ *  Copyright (c) 2009 Daniel Mack <daniel@caiaq.de>
+ *  Copyright (c) 2009 Janine Kropp <nin@directfb.org>
+ *  Copyright (c) 2009 Denis Oliver Kropp <dok@directfb.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+/*
+ * WARNING: This controller is attached to System Bus 2 of the PXA which
+ * needs its arbiter to be enabled explictly (CKENB & 1<<9).
+ * There is currently no way to do this from Linux, so you need to teach
+ * your bootloader for now.
+ */
+
+#include <linux/module.h>
+#include <linux/version.h>
+
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/miscdevice.h>
+#include <linux/interrupt.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+#include <linux/ioctl.h>
+#include <linux/delay.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+
+#include "pxa3xx-gcu.h"
+
+#define DRV_NAME        "pxa3xx-gcu"
+#define MISCDEV_MINOR   197
+
+#define REG_GCCR        0x00
+#define GCCR_SYNC_CLR   (1 << 9)
+#define GCCR_BP_RST     (1 << 8)
+#define GCCR_ABORT      (1 << 6)
+#define GCCR_STOP       (1 << 4)
+
+#define REG_GCISCR      0x04
+#define REG_GCIECR      0x08
+#define REG_GCRBBR      0x20
+#define REG_GCRBLR      0x24
+#define REG_GCRBHR      0x28
+#define REG_GCRBTR      0x2C
+#define REG_GCRBEXHR    0x30
+
+#define IE_EOB          (1 << 0)
+#define IE_EEOB         (1 << 5)
+#define IE_ALL          0xff
+
+#define SHARED_SIZE     PAGE_ALIGN(sizeof(struct pxa3xx_gcu_shared))
+
+/* #define PXA3XX_GCU_DEBUG */
+/* #define PXA3XX_GCU_DEBUG_TIMER */
+
+#ifdef PXA3XX_GCU_DEBUG
+#define QDUMP(msg)                                      \
+        do {                                            \
+                QPRINT(priv, KERN_DEBUG, msg);          \
+        } while (0)
+#else
+#define QDUMP(msg)      do {} while (0)
+#endif
+
+#define QERROR(msg)                                     \
+        do {                                            \
+                QPRINT(priv, KERN_ERR, msg);            \
+        } while (0)
+
+struct pxa3xx_gcu_batch {
+        struct pxa3xx_gcu_batch *next;
+        u32                     *ptr;
+        dma_addr_t               phys;
+        unsigned long            length;
+};
+
+struct pxa3xx_gcu_priv {
+        void __iomem             *mmio_base;
+        struct clk               *clk;
+        struct pxa3xx_gcu_shared *shared;
+        dma_addr_t                shared_phys;
+        struct resource          *resource_mem;
+        struct miscdevice         misc_dev;
+        struct file_operations    misc_fops;
+        wait_queue_head_t         wait_idle;
+        wait_queue_head_t         wait_free;
+        spinlock_t                spinlock;
+        struct timeval            base_time;
+
+        struct pxa3xx_gcu_batch *free;
+
+        struct pxa3xx_gcu_batch *ready;
+        struct pxa3xx_gcu_batch *ready_last;
+        struct pxa3xx_gcu_batch *running;
+};
+
+static inline unsigned long
+gc_readl(struct pxa3xx_gcu_priv *priv, unsigned int off)
+{
+        return __raw_readl(priv->mmio_base + off);
+}
+
+static inline void
+gc_writel(struct pxa3xx_gcu_priv *priv, unsigned int off, unsigned long val)
+{
+        __raw_writel(val, priv->mmio_base + off);
+}
+
+#define QPRINT(priv, level, msg)                                        \
+        do {                                                            \
+                struct timeval tv;                                      \
+                struct pxa3xx_gcu_shared *shared = priv->shared;        \
+                u32 base = gc_readl(priv, REG_GCRBBR);                  \
+                                                                        \
+                do_gettimeofday(&tv);                                   \
+                                                                        \
+                printk(level "%ld.%03ld.%03ld - %-17s: %-21s (%s, "     \
+                        "STATUS "                                       \
+                        "0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, "    \
+                        "T %5ld)\n",                                    \
+                        tv.tv_sec - priv->base_time.tv_sec,             \
+                        tv.tv_usec / 1000, tv.tv_usec % 1000,           \
+                        __func__, msg,                                  \
+                        shared->hw_running ? "running" : "   idle",     \
+                        gc_readl(priv, REG_GCISCR),                     \
+                        gc_readl(priv, REG_GCRBBR),                     \
+                        gc_readl(priv, REG_GCRBLR),                     \
+                        (gc_readl(priv, REG_GCRBEXHR) - base) / 4,      \
+                        (gc_readl(priv, REG_GCRBHR) - base) / 4,        \
+                        (gc_readl(priv, REG_GCRBTR) - base) / 4);       \
+        } while (0)
+
+static void
+pxa3xx_gcu_reset(struct pxa3xx_gcu_priv *priv)
+{
+        QDUMP("RESET");
+
+        /* disable interrupts */
+        gc_writel(priv, REG_GCIECR, 0);
+
+        /* reset hardware */
+        gc_writel(priv, REG_GCCR, GCCR_ABORT);
+        gc_writel(priv, REG_GCCR, 0);
+
+        memset(priv->shared, 0, SHARED_SIZE);
+        priv->shared->buffer_phys = priv->shared_phys;
+        priv->shared->magic = PXA3XX_GCU_SHARED_MAGIC;
+
+        do_gettimeofday(&priv->base_time);
+
+        /* set up the ring buffer pointers */
+        gc_writel(priv, REG_GCRBLR, 0);
+        gc_writel(priv, REG_GCRBBR, priv->shared_phys);
+        gc_writel(priv, REG_GCRBTR, priv->shared_phys);
+
+        /* enable all IRQs except EOB */
+        gc_writel(priv, REG_GCIECR, IE_ALL & ~IE_EOB);
+}
+
+static void
+dump_whole_state(struct pxa3xx_gcu_priv *priv)
+{
+        struct pxa3xx_gcu_shared *sh = priv->shared;
+        u32 base = gc_readl(priv, REG_GCRBBR);
+
+        QDUMP("DUMP");
+
+        printk(KERN_DEBUG "== PXA3XX-GCU DUMP ==\n"
+                "%s, STATUS 0x%02lx, B 0x%08lx [%ld], E %5ld, H %5ld, T %5ld\n",
+                sh->hw_running ? "running" : "idle   ",
+                gc_readl(priv, REG_GCISCR),
+                gc_readl(priv, REG_GCRBBR),
+                gc_readl(priv, REG_GCRBLR),
+                (gc_readl(priv, REG_GCRBEXHR) - base) / 4,
+                (gc_readl(priv, REG_GCRBHR) - base) / 4,
+                (gc_readl(priv, REG_GCRBTR) - base) / 4);
+}
+
+static void
+flush_running(struct pxa3xx_gcu_priv *priv)
+{
+        struct pxa3xx_gcu_batch *running = priv->running;
+        struct pxa3xx_gcu_batch *next;
+
+        while (running) {
+                next = running->next;
+                running->next = priv->free;
+                priv->free = running;
+                running = next;
+        }
+
+        priv->running = NULL;
+}
+
+static void
+run_ready(struct pxa3xx_gcu_priv *priv)
+{
+        unsigned int num = 0;
+        struct pxa3xx_gcu_shared *shared = priv->shared;
+        struct pxa3xx_gcu_batch *ready = priv->ready;
+
+        QDUMP("Start");
+
+        BUG_ON(!ready);
+
+        shared->buffer[num++] = 0x05000000;
+
+        while (ready) {
+                shared->buffer[num++] = 0x00000001;
+                shared->buffer[num++] = ready->phys;
+                ready = ready->next;
+        }
+
+        shared->buffer[num++] = 0x05000000;
+        priv->running = priv->ready;
+        priv->ready = priv->ready_last = NULL;
+        gc_writel(priv, REG_GCRBLR, 0);
+        shared->hw_running = 1;
+
+        /* ring base address */
+        gc_writel(priv, REG_GCRBBR, shared->buffer_phys);
+
+        /* ring tail address */
+        gc_writel(priv, REG_GCRBTR, shared->buffer_phys + num * 4);
+
+        /* ring length */
+        gc_writel(priv, REG_GCRBLR, ((num + 63) & ~63) * 4);
+}
+
+static irqreturn_t
+pxa3xx_gcu_handle_irq(int irq, void *ctx)
+{
+        struct pxa3xx_gcu_priv *priv = ctx;
+        struct pxa3xx_gcu_shared *shared = priv->shared;
+        u32 status = gc_readl(priv, REG_GCISCR) & IE_ALL;
+
+        QDUMP("-Interrupt");
+
+        if (!status)
+                return IRQ_NONE;
+
+        spin_lock(&priv->spinlock);
+        shared->num_interrupts++;
+
+        if (status & IE_EEOB) {
+                QDUMP(" [EEOB]");
+
+                flush_running(priv);
+                wake_up_all(&priv->wait_free);
+
+                if (priv->ready) {
+                        run_ready(priv);
+                } else {
+                        /* There is no more data prepared by the userspace.
+                         * Set hw_running = 0 and wait for the next userspace
+                         * kick-off */
+                        shared->num_idle++;
+                        shared->hw_running = 0;
+
+                        QDUMP(" '-> Idle.");
+
+                        /* set ring buffer length to zero */
+                        gc_writel(priv, REG_GCRBLR, 0);
+
+                        wake_up_all(&priv->wait_idle);
+                }
+
+                shared->num_done++;
+        } else {
+                QERROR(" [???]");
+                dump_whole_state(priv);
+        }
+
+        /* Clear the interrupt */
+        gc_writel(priv, REG_GCISCR, status);
+        spin_unlock(&priv->spinlock);
+
+        return IRQ_HANDLED;
+}
+
+static int
+pxa3xx_gcu_wait_idle(struct pxa3xx_gcu_priv *priv)
+{
+        int ret = 0;
+
+        QDUMP("Waiting for idle...");
+
+        /* Does not need to be atomic. There's a lock in user space,
+         * but anyhow, this is just for statistics. */
+        priv->shared->num_wait_idle++;
+
+        while (priv->shared->hw_running) {
+                int num = priv->shared->num_interrupts;
+                u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
+
+                ret = wait_event_interruptible_timeout(priv->wait_idle,
+                                        !priv->shared->hw_running, HZ*4);
+
+                if (ret < 0)
+                        break;
+
+                if (ret > 0)
+                        continue;
+
+                if (gc_readl(priv, REG_GCRBEXHR) == rbexhr &&
+                    priv->shared->num_interrupts == num) {
+                        QERROR("TIMEOUT");
+                        ret = -ETIMEDOUT;
+                        break;
+                }
+        }
+
+        QDUMP("done");
+
+        return ret;
+}
+
+static int
+pxa3xx_gcu_wait_free(struct pxa3xx_gcu_priv *priv)
+{
+        int ret = 0;
+
+        QDUMP("Waiting for free...");
+
+        /* Does not need to be atomic. There's a lock in user space,
+         * but anyhow, this is just for statistics. */
+        priv->shared->num_wait_free++;
+
+        while (!priv->free) {
+                u32 rbexhr = gc_readl(priv, REG_GCRBEXHR);
+
+                ret = wait_event_interruptible_timeout(priv->wait_free,
+                                                       priv->free, HZ*4);
+
+                if (ret < 0)
+                        break;
+
+                if (ret > 0)
+                        continue;
+
+                if (gc_readl(priv, REG_GCRBEXHR) == rbexhr) {
+                        QERROR("TIMEOUT");
+                        ret = -ETIMEDOUT;
+                        break;
+                }
+        }
+
+        QDUMP("done");
+
+        return ret;
+}
+
+/* Misc device layer */
+
+static ssize_t
+pxa3xx_gcu_misc_write(struct file *filp, const char *buff,
+                      size_t count, loff_t *offp)
+{
+        int ret;
+        unsigned long flags;
+        struct pxa3xx_gcu_batch *buffer;
+        struct pxa3xx_gcu_priv *priv =
+                container_of(filp->f_op, struct pxa3xx_gcu_priv, misc_fops);
+
+        int words = count / 4;
+
+        /* Does not need to be atomic. There's a lock in user space,
+         * but anyhow, this is just for statistics. */
+        priv->shared->num_writes++;
+
+        priv->shared->num_words += words;
+
+        /* Last word reserved for batch buffer end command */
+        if (words >= PXA3XX_GCU_BATCH_WORDS)
+                return -E2BIG;
+
+        /* Wait for a free buffer */
+        if (!priv->free) {
+                ret = pxa3xx_gcu_wait_free(priv);
+                if (ret < 0)
+                        return ret;
+        }
+
+        /*
+         * Get buffer from free list
+         */
+        spin_lock_irqsave(&priv->spinlock, flags);
+
+        buffer = priv->free;
+        priv->free = buffer->next;
+
+        spin_unlock_irqrestore(&priv->spinlock, flags);
+
+
+        /* Copy data from user into buffer */
+        ret = copy_from_user(buffer->ptr, buff, words * 4);
+        if (ret) {
+                spin_lock_irqsave(&priv->spinlock, flags);
+                buffer->next = priv->free;
+                priv->free = buffer;
+                spin_unlock_irqrestore(&priv->spinlock, flags);
+                return ret;
+        }
+
+        buffer->length = words;
+
+        /* Append batch buffer end command */
+        buffer->ptr[words] = 0x01000000;
+
+        /*
+         * Add buffer to ready list
+         */
+        spin_lock_irqsave(&priv->spinlock, flags);
+
+        buffer->next = NULL;
+
+        if (priv->ready) {
+                BUG_ON(priv->ready_last == NULL);
+
+                priv->ready_last->next = buffer;
+        } else
+                priv->ready = buffer;
+
+        priv->ready_last = buffer;
+
+        if (!priv->shared->hw_running)
+                run_ready(priv);
+
+        spin_unlock_irqrestore(&priv->spinlock, flags);
+
+        return words * 4;
+}
+
+
+static long
+pxa3xx_gcu_misc_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+        unsigned long flags;
+        struct pxa3xx_gcu_priv *priv =
+                container_of(filp->f_op, struct pxa3xx_gcu_priv, misc_fops);
+
+        switch (cmd) {
+        case PXA3XX_GCU_IOCTL_RESET:
+                spin_lock_irqsave(&priv->spinlock, flags);
+                pxa3xx_gcu_reset(priv);
+                spin_unlock_irqrestore(&priv->spinlock, flags);
+                return 0;
+
+        case PXA3XX_GCU_IOCTL_WAIT_IDLE:
+                return pxa3xx_gcu_wait_idle(priv);
+        }
+
+        return -ENOSYS;
+}
+
+static int
+pxa3xx_gcu_misc_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+        unsigned int size = vma->vm_end - vma->vm_start;
+        struct pxa3xx_gcu_priv *priv =
+                container_of(filp->f_op, struct pxa3xx_gcu_priv, misc_fops);
+
+        switch (vma->vm_pgoff) {
+        case 0:
+                /* hand out the shared data area */
+                if (size != SHARED_SIZE)
+                        return -EINVAL;
+
+                return dma_mmap_coherent(NULL, vma,
+                        priv->shared, priv->shared_phys, size);
+
+        case SHARED_SIZE >> PAGE_SHIFT:
+                /* hand out the MMIO base for direct register access
+                 * from userspace */
+                if (size != resource_size(priv->resource_mem))
+                        return -EINVAL;
+
+                vma->vm_flags |= VM_IO;
+                vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+                return io_remap_pfn_range(vma, vma->vm_start,
+                                priv->resource_mem->start >> PAGE_SHIFT,
+                                size, vma->vm_page_prot);
+        }
+
+        return -EINVAL;
+}
+
+
+#ifdef PXA3XX_GCU_DEBUG_TIMER
+static struct timer_list pxa3xx_gcu_debug_timer;
+
+static void pxa3xx_gcu_debug_timedout(unsigned long ptr)
+{
+        struct pxa3xx_gcu_priv *priv = (struct pxa3xx_gcu_priv *) ptr;
+
+        QERROR("Timer DUMP");
+
+        /* init the timer structure */
+        init_timer(&pxa3xx_gcu_debug_timer);
+        pxa3xx_gcu_debug_timer.function = pxa3xx_gcu_debug_timedout;
+        pxa3xx_gcu_debug_timer.data = ptr;
+        pxa3xx_gcu_debug_timer.expires = jiffies + 5*HZ; /* one second */
+
+        add_timer(&pxa3xx_gcu_debug_timer);
+}
+
+static void pxa3xx_gcu_init_debug_timer(void)
+{
+        pxa3xx_gcu_debug_timedout((unsigned long) &pxa3xx_gcu_debug_timer);
+}
+#else
+static inline void pxa3xx_gcu_init_debug_timer(void) {}
+#endif
+
+static int
+add_buffer(struct platform_device *dev,
+           struct pxa3xx_gcu_priv *priv)
+{
+        struct pxa3xx_gcu_batch *buffer;
+
+        buffer = kzalloc(sizeof(struct pxa3xx_gcu_batch), GFP_KERNEL);
+        if (!buffer)
+                return -ENOMEM;
+
+        buffer->ptr = dma_alloc_coherent(&dev->dev, PXA3XX_GCU_BATCH_WORDS * 4,
+                                         &buffer->phys, GFP_KERNEL);
+        if (!buffer->ptr) {
+                kfree(buffer);
+                return -ENOMEM;
+        }
+
+        buffer->next = priv->free;
+
+        priv->free = buffer;
+
+        return 0;
+}
+
+static void
+free_buffers(struct platform_device *dev,
+             struct pxa3xx_gcu_priv *priv)
+{
+        struct pxa3xx_gcu_batch *next, *buffer = priv->free;
+
+        while (buffer) {
+                next = buffer->next;
+
+                dma_free_coherent(&dev->dev, PXA3XX_GCU_BATCH_WORDS * 4,
+                                  buffer->ptr, buffer->phys);
+
+                kfree(buffer);
+
+                buffer = next;
+        }
+
+        priv->free = NULL;
+}
+
+static int __devinit
+pxa3xx_gcu_probe(struct platform_device *dev)
+{
+        int i, ret, irq;
+        struct resource *r;
+        struct pxa3xx_gcu_priv *priv;
+
+        priv = kzalloc(sizeof(struct pxa3xx_gcu_priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
+        for (i = 0; i < 8; i++) {
+                ret = add_buffer(dev, priv);
+                if (ret) {
+                        dev_err(&dev->dev, "failed to allocate DMA memory\n");
+                        goto err_free_priv;
+                }
+        }
+
+        init_waitqueue_head(&priv->wait_idle);
+        init_waitqueue_head(&priv->wait_free);
+        spin_lock_init(&priv->spinlock);
+
+        /* we allocate the misc device structure as part of our own allocation,
+         * so we can get a pointer to our priv structure later on with
+         * container_of(). This isn't really necessary as we have a fixed minor
+         * number anyway, but this is to avoid statics. */
+
+        priv->misc_fops.owner   = THIS_MODULE;
+        priv->misc_fops.write   = pxa3xx_gcu_misc_write;
+        priv->misc_fops.unlocked_ioctl = pxa3xx_gcu_misc_ioctl;
+        priv->misc_fops.mmap    = pxa3xx_gcu_misc_mmap;
+
+        priv->misc_dev.minor    = MISCDEV_MINOR,
+        priv->misc_dev.name     = DRV_NAME,
+        priv->misc_dev.fops     = &priv->misc_fops,
+
+        /* register misc device */
+        ret = misc_register(&priv->misc_dev);
+        if (ret < 0) {
+                dev_err(&dev->dev, "misc_register() for minor %d failed\n",
+                        MISCDEV_MINOR);
+                goto err_free_priv;
+        }
+
+        /* handle IO resources */
+        r = platform_get_resource(dev, IORESOURCE_MEM, 0);
+        if (r == NULL) {
+                dev_err(&dev->dev, "no I/O memory resource defined\n");
+                ret = -ENODEV;
+                goto err_misc_deregister;
+        }
+
+        if (!request_mem_region(r->start, resource_size(r), dev->name)) {
+                dev_err(&dev->dev, "failed to request I/O memory\n");
+                ret = -EBUSY;
+                goto err_misc_deregister;
+        }
+
+        priv->mmio_base = ioremap_nocache(r->start, resource_size(r));
+        if (!priv->mmio_base) {
+                dev_err(&dev->dev, "failed to map I/O memory\n");
+                ret = -EBUSY;
+                goto err_free_mem_region;
+        }
+
+        /* allocate dma memory */
+        priv->shared = dma_alloc_coherent(&dev->dev, SHARED_SIZE,
+                                          &priv->shared_phys, GFP_KERNEL);
+
+        if (!priv->shared) {
+                dev_err(&dev->dev, "failed to allocate DMA memory\n");
+                ret = -ENOMEM;
+                goto err_free_io;
+        }
+
+        /* enable the clock */
+        priv->clk = clk_get(&dev->dev, NULL);
+        if (IS_ERR(priv->clk)) {
+                dev_err(&dev->dev, "failed to get clock\n");
+                ret = -ENODEV;
+                goto err_free_dma;
+        }
+
+        ret = clk_enable(priv->clk);
+        if (ret < 0) {
+                dev_err(&dev->dev, "failed to enable clock\n");
+                goto err_put_clk;
+        }
+
+        /* request the IRQ */
+        irq = platform_get_irq(dev, 0);
+        if (irq < 0) {
+                dev_err(&dev->dev, "no IRQ defined\n");
+                ret = -ENODEV;
+                goto err_put_clk;
+        }
+
+        ret = request_irq(irq, pxa3xx_gcu_handle_irq,
+                          IRQF_DISABLED, DRV_NAME, priv);
+        if (ret) {
+                dev_err(&dev->dev, "request_irq failed\n");
+                ret = -EBUSY;
+                goto err_put_clk;
+        }
+
+        platform_set_drvdata(dev, priv);
+        priv->resource_mem = r;
+        pxa3xx_gcu_reset(priv);
+        pxa3xx_gcu_init_debug_timer();
+
+        dev_info(&dev->dev, "registered @0x%p, DMA 0x%p (%d bytes), IRQ %d\n",
+                        (void *) r->start, (void *) priv->shared_phys,
+                        SHARED_SIZE, irq);
+        return 0;
+
+err_put_clk:
+        clk_disable(priv->clk);
+        clk_put(priv->clk);
+
+err_free_dma:
+        dma_free_coherent(&dev->dev, SHARED_SIZE,
+                        priv->shared, priv->shared_phys);
+
+err_free_io:
+        iounmap(priv->mmio_base);
+
+err_free_mem_region:
+        release_mem_region(r->start, resource_size(r));
+
+err_misc_deregister:
+        misc_deregister(&priv->misc_dev);
+
+err_free_priv:
+        platform_set_drvdata(dev, NULL);
+        free_buffers(dev, priv);
+        kfree(priv);
+        return ret;
+}
+
+static int __devexit
+pxa3xx_gcu_remove(struct platform_device *dev)
+{
+        struct pxa3xx_gcu_priv *priv = platform_get_drvdata(dev);
+        struct resource *r = priv->resource_mem;
+
+        pxa3xx_gcu_wait_idle(priv);
+
+        misc_deregister(&priv->misc_dev);
+        dma_free_coherent(&dev->dev, SHARED_SIZE,
+                        priv->shared, priv->shared_phys);
+        iounmap(priv->mmio_base);
+        release_mem_region(r->start, resource_size(r));
+        platform_set_drvdata(dev, NULL);
+        clk_disable(priv->clk);
+        free_buffers(dev, priv);
+        kfree(priv);
+
+        return 0;
+}
+
+static struct platform_driver pxa3xx_gcu_driver = {
+        .probe    = pxa3xx_gcu_probe,
+        .remove  = __devexit_p(pxa3xx_gcu_remove),
+        .driver  = {
+                .owner  = THIS_MODULE,
+                .name   = DRV_NAME,
+        },
+};
+
+static int __init
+pxa3xx_gcu_init(void)
+{
+        return platform_driver_register(&pxa3xx_gcu_driver);
+}
+
+static void __exit
+pxa3xx_gcu_exit(void)
+{
+        platform_driver_unregister(&pxa3xx_gcu_driver);
+}
+
+module_init(pxa3xx_gcu_init);
+module_exit(pxa3xx_gcu_exit);
+
+MODULE_DESCRIPTION("PXA3xx graphics controller unit driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_MISCDEV(MISCDEV_MINOR);
+MODULE_AUTHOR("Janine Kropp <nin@directfb.org>, "
+                "Denis Oliver Kropp <dok@directfb.org>, "
+                "Daniel Mack <daniel@caiaq.de>");