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-rw-r--r--arch/arm/mach-bcmring/dma.c2321
1 files changed, 2321 insertions, 0 deletions
diff --git a/arch/arm/mach-bcmring/dma.c b/arch/arm/mach-bcmring/dma.c
new file mode 100644
index 000000000000..7b20fccb9d4e
--- /dev/null
+++ b/arch/arm/mach-bcmring/dma.c
@@ -0,0 +1,2321 @@
+/*****************************************************************************
+* Copyright 2004 - 2008 Broadcom Corporation. All rights reserved.
+*
+* Unless you and Broadcom execute a separate written software license
+* agreement governing use of this software, this software is licensed to you
+* under the terms of the GNU General Public License version 2, available at
+* http://www.broadcom.com/licenses/GPLv2.php (the "GPL").
+*
+* Notwithstanding the above, under no circumstances may you combine this
+* software in any way with any other Broadcom software provided under a
+* license other than the GPL, without Broadcom's express prior written
+* consent.
+*****************************************************************************/
+
+/****************************************************************************/
+/**
+* @file dma.c
+*
+* @brief Implements the DMA interface.
+*/
+/****************************************************************************/
+
+/* ---- Include Files ---------------------------------------------------- */
+
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/proc_fs.h>
+
+#include <mach/timer.h>
+
+#include <linux/mm.h>
+#include <linux/pfn.h>
+#include <asm/atomic.h>
+#include <mach/dma.h>
+
+/* I don't quite understand why dc4 fails when this is set to 1 and DMA is enabled */
+/* especially since dc4 doesn't use kmalloc'd memory. */
+
+#define ALLOW_MAP_OF_KMALLOC_MEMORY 0
+
+/* ---- Public Variables ------------------------------------------------- */
+
+/* ---- Private Constants and Types -------------------------------------- */
+
+#define MAKE_HANDLE(controllerIdx, channelIdx) (((controllerIdx) << 4) | (channelIdx))
+
+#define CONTROLLER_FROM_HANDLE(handle) (((handle) >> 4) & 0x0f)
+#define CHANNEL_FROM_HANDLE(handle) ((handle) & 0x0f)
+
+#define DMA_MAP_DEBUG 0
+
+#if DMA_MAP_DEBUG
+# define DMA_MAP_PRINT(fmt, args...) printk("%s: " fmt, __func__, ## args)
+#else
+# define DMA_MAP_PRINT(fmt, args...)
+#endif
+
+/* ---- Private Variables ------------------------------------------------ */
+
+static DMA_Global_t gDMA;
+static struct proc_dir_entry *gDmaDir;
+
+static atomic_t gDmaStatMemTypeKmalloc = ATOMIC_INIT(0);
+static atomic_t gDmaStatMemTypeVmalloc = ATOMIC_INIT(0);
+static atomic_t gDmaStatMemTypeUser = ATOMIC_INIT(0);
+static atomic_t gDmaStatMemTypeCoherent = ATOMIC_INIT(0);
+
+#include "dma_device.c"
+
+/* ---- Private Function Prototypes -------------------------------------- */
+
+/* ---- Functions ------------------------------------------------------- */
+
+/****************************************************************************/
+/**
+* Displays information for /proc/dma/mem-type
+*/
+/****************************************************************************/
+
+static int dma_proc_read_mem_type(char *buf, char **start, off_t offset,
+ int count, int *eof, void *data)
+{
+ int len = 0;
+
+ len += sprintf(buf + len, "dma_map_mem statistics\n");
+ len +=
+ sprintf(buf + len, "coherent: %d\n",
+ atomic_read(&gDmaStatMemTypeCoherent));
+ len +=
+ sprintf(buf + len, "kmalloc: %d\n",
+ atomic_read(&gDmaStatMemTypeKmalloc));
+ len +=
+ sprintf(buf + len, "vmalloc: %d\n",
+ atomic_read(&gDmaStatMemTypeVmalloc));
+ len +=
+ sprintf(buf + len, "user: %d\n",
+ atomic_read(&gDmaStatMemTypeUser));
+
+ return len;
+}
+
+/****************************************************************************/
+/**
+* Displays information for /proc/dma/channels
+*/
+/****************************************************************************/
+
+static int dma_proc_read_channels(char *buf, char **start, off_t offset,
+ int count, int *eof, void *data)
+{
+ int controllerIdx;
+ int channelIdx;
+ int limit = count - 200;
+ int len = 0;
+ DMA_Channel_t *channel;
+
+ if (down_interruptible(&gDMA.lock) < 0) {
+ return -ERESTARTSYS;
+ }
+
+ for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
+ controllerIdx++) {
+ for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
+ channelIdx++) {
+ if (len >= limit) {
+ break;
+ }
+
+ channel =
+ &gDMA.controller[controllerIdx].channel[channelIdx];
+
+ len +=
+ sprintf(buf + len, "%d:%d ", controllerIdx,
+ channelIdx);
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
+ 0) {
+ len +=
+ sprintf(buf + len, "Dedicated for %s ",
+ DMA_gDeviceAttribute[channel->
+ devType].name);
+ } else {
+ len += sprintf(buf + len, "Shared ");
+ }
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) != 0) {
+ len += sprintf(buf + len, "No ISR ");
+ }
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_LARGE_FIFO) != 0) {
+ len += sprintf(buf + len, "Fifo: 128 ");
+ } else {
+ len += sprintf(buf + len, "Fifo: 64 ");
+ }
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_IN_USE) != 0) {
+ len +=
+ sprintf(buf + len, "InUse by %s",
+ DMA_gDeviceAttribute[channel->
+ devType].name);
+#if (DMA_DEBUG_TRACK_RESERVATION)
+ len +=
+ sprintf(buf + len, " (%s:%d)",
+ channel->fileName,
+ channel->lineNum);
+#endif
+ } else {
+ len += sprintf(buf + len, "Avail ");
+ }
+
+ if (channel->lastDevType != DMA_DEVICE_NONE) {
+ len +=
+ sprintf(buf + len, "Last use: %s ",
+ DMA_gDeviceAttribute[channel->
+ lastDevType].
+ name);
+ }
+
+ len += sprintf(buf + len, "\n");
+ }
+ }
+ up(&gDMA.lock);
+ *eof = 1;
+
+ return len;
+}
+
+/****************************************************************************/
+/**
+* Displays information for /proc/dma/devices
+*/
+/****************************************************************************/
+
+static int dma_proc_read_devices(char *buf, char **start, off_t offset,
+ int count, int *eof, void *data)
+{
+ int limit = count - 200;
+ int len = 0;
+ int devIdx;
+
+ if (down_interruptible(&gDMA.lock) < 0) {
+ return -ERESTARTSYS;
+ }
+
+ for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
+ DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
+
+ if (devAttr->name == NULL) {
+ continue;
+ }
+
+ if (len >= limit) {
+ break;
+ }
+
+ len += sprintf(buf + len, "%-12s ", devAttr->name);
+
+ if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
+ len +=
+ sprintf(buf + len, "Dedicated %d:%d ",
+ devAttr->dedicatedController,
+ devAttr->dedicatedChannel);
+ } else {
+ len += sprintf(buf + len, "Shared DMA:");
+ if ((devAttr->flags & DMA_DEVICE_FLAG_ON_DMA0) != 0) {
+ len += sprintf(buf + len, "0");
+ }
+ if ((devAttr->flags & DMA_DEVICE_FLAG_ON_DMA1) != 0) {
+ len += sprintf(buf + len, "1");
+ }
+ len += sprintf(buf + len, " ");
+ }
+ if ((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0) {
+ len += sprintf(buf + len, "NoISR ");
+ }
+ if ((devAttr->flags & DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO) != 0) {
+ len += sprintf(buf + len, "Allow-128 ");
+ }
+
+ len +=
+ sprintf(buf + len,
+ "Xfer #: %Lu Ticks: %Lu Bytes: %Lu DescLen: %u\n",
+ devAttr->numTransfers, devAttr->transferTicks,
+ devAttr->transferBytes,
+ devAttr->ring.bytesAllocated);
+
+ }
+
+ up(&gDMA.lock);
+ *eof = 1;
+
+ return len;
+}
+
+/****************************************************************************/
+/**
+* Determines if a DMA_Device_t is "valid".
+*
+* @return
+* TRUE - dma device is valid
+* FALSE - dma device isn't valid
+*/
+/****************************************************************************/
+
+static inline int IsDeviceValid(DMA_Device_t device)
+{
+ return (device >= 0) && (device < DMA_NUM_DEVICE_ENTRIES);
+}
+
+/****************************************************************************/
+/**
+* Translates a DMA handle into a pointer to a channel.
+*
+* @return
+* non-NULL - pointer to DMA_Channel_t
+* NULL - DMA Handle was invalid
+*/
+/****************************************************************************/
+
+static inline DMA_Channel_t *HandleToChannel(DMA_Handle_t handle)
+{
+ int controllerIdx;
+ int channelIdx;
+
+ controllerIdx = CONTROLLER_FROM_HANDLE(handle);
+ channelIdx = CHANNEL_FROM_HANDLE(handle);
+
+ if ((controllerIdx > DMA_NUM_CONTROLLERS)
+ || (channelIdx > DMA_NUM_CHANNELS)) {
+ return NULL;
+ }
+ return &gDMA.controller[controllerIdx].channel[channelIdx];
+}
+
+/****************************************************************************/
+/**
+* Interrupt handler which is called to process DMA interrupts.
+*/
+/****************************************************************************/
+
+static irqreturn_t dma_interrupt_handler(int irq, void *dev_id)
+{
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+ int irqStatus;
+
+ channel = (DMA_Channel_t *) dev_id;
+
+ /* Figure out why we were called, and knock down the interrupt */
+
+ irqStatus = dmacHw_getInterruptStatus(channel->dmacHwHandle);
+ dmacHw_clearInterrupt(channel->dmacHwHandle);
+
+ if ((channel->devType < 0)
+ || (channel->devType > DMA_NUM_DEVICE_ENTRIES)) {
+ printk(KERN_ERR "dma_interrupt_handler: Invalid devType: %d\n",
+ channel->devType);
+ return IRQ_NONE;
+ }
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+
+ /* Update stats */
+
+ if ((irqStatus & dmacHw_INTERRUPT_STATUS_TRANS) != 0) {
+ devAttr->transferTicks +=
+ (timer_get_tick_count() - devAttr->transferStartTime);
+ }
+
+ if ((irqStatus & dmacHw_INTERRUPT_STATUS_ERROR) != 0) {
+ printk(KERN_ERR
+ "dma_interrupt_handler: devType :%d DMA error (%s)\n",
+ channel->devType, devAttr->name);
+ } else {
+ devAttr->numTransfers++;
+ devAttr->transferBytes += devAttr->numBytes;
+ }
+
+ /* Call any installed handler */
+
+ if (devAttr->devHandler != NULL) {
+ devAttr->devHandler(channel->devType, irqStatus,
+ devAttr->userData);
+ }
+
+ return IRQ_HANDLED;
+}
+
+/****************************************************************************/
+/**
+* Allocates memory to hold a descriptor ring. The descriptor ring then
+* needs to be populated by making one or more calls to
+* dna_add_descriptors.
+*
+* The returned descriptor ring will be automatically initialized.
+*
+* @return
+* 0 Descriptor ring was allocated successfully
+* -EINVAL Invalid parameters passed in
+* -ENOMEM Unable to allocate memory for the desired number of descriptors.
+*/
+/****************************************************************************/
+
+int dma_alloc_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to populate */
+ int numDescriptors /* Number of descriptors that need to be allocated. */
+ ) {
+ size_t bytesToAlloc = dmacHw_descriptorLen(numDescriptors);
+
+ if ((ring == NULL) || (numDescriptors <= 0)) {
+ return -EINVAL;
+ }
+
+ ring->physAddr = 0;
+ ring->descriptorsAllocated = 0;
+ ring->bytesAllocated = 0;
+
+ ring->virtAddr = dma_alloc_writecombine(NULL,
+ bytesToAlloc,
+ &ring->physAddr,
+ GFP_KERNEL);
+ if (ring->virtAddr == NULL) {
+ return -ENOMEM;
+ }
+
+ ring->bytesAllocated = bytesToAlloc;
+ ring->descriptorsAllocated = numDescriptors;
+
+ return dma_init_descriptor_ring(ring, numDescriptors);
+}
+
+EXPORT_SYMBOL(dma_alloc_descriptor_ring);
+
+/****************************************************************************/
+/**
+* Releases the memory which was previously allocated for a descriptor ring.
+*/
+/****************************************************************************/
+
+void dma_free_descriptor_ring(DMA_DescriptorRing_t *ring /* Descriptor to release */
+ ) {
+ if (ring->virtAddr != NULL) {
+ dma_free_writecombine(NULL,
+ ring->bytesAllocated,
+ ring->virtAddr, ring->physAddr);
+ }
+
+ ring->bytesAllocated = 0;
+ ring->descriptorsAllocated = 0;
+ ring->virtAddr = NULL;
+ ring->physAddr = 0;
+}
+
+EXPORT_SYMBOL(dma_free_descriptor_ring);
+
+/****************************************************************************/
+/**
+* Initializes a descriptor ring, so that descriptors can be added to it.
+* Once a descriptor ring has been allocated, it may be reinitialized for
+* use with additional/different regions of memory.
+*
+* Note that if 7 descriptors are allocated, it's perfectly acceptable to
+* initialize the ring with a smaller number of descriptors. The amount
+* of memory allocated for the descriptor ring will not be reduced, and
+* the descriptor ring may be reinitialized later
+*
+* @return
+* 0 Descriptor ring was initialized successfully
+* -ENOMEM The descriptor which was passed in has insufficient space
+* to hold the desired number of descriptors.
+*/
+/****************************************************************************/
+
+int dma_init_descriptor_ring(DMA_DescriptorRing_t *ring, /* Descriptor ring to initialize */
+ int numDescriptors /* Number of descriptors to initialize. */
+ ) {
+ if (ring->virtAddr == NULL) {
+ return -EINVAL;
+ }
+ if (dmacHw_initDescriptor(ring->virtAddr,
+ ring->physAddr,
+ ring->bytesAllocated, numDescriptors) < 0) {
+ printk(KERN_ERR
+ "dma_init_descriptor_ring: dmacHw_initDescriptor failed\n");
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_init_descriptor_ring);
+
+/****************************************************************************/
+/**
+* Determines the number of descriptors which would be required for a
+* transfer of the indicated memory region.
+*
+* This function also needs to know which DMA device this transfer will
+* be destined for, so that the appropriate DMA configuration can be retrieved.
+* DMA parameters such as transfer width, and whether this is a memory-to-memory
+* or memory-to-peripheral, etc can all affect the actual number of descriptors
+* required.
+*
+* @return
+* > 0 Returns the number of descriptors required for the indicated transfer
+* -ENODEV - Device handed in is invalid.
+* -EINVAL Invalid parameters
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_calculate_descriptor_count(DMA_Device_t device, /* DMA Device that this will be associated with */
+ dma_addr_t srcData, /* Place to get data to write to device */
+ dma_addr_t dstData, /* Pointer to device data address */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ ) {
+ int numDescriptors;
+ DMA_DeviceAttribute_t *devAttr;
+
+ if (!IsDeviceValid(device)) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[device];
+
+ numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
+ (void *)srcData,
+ (void *)dstData,
+ numBytes);
+ if (numDescriptors < 0) {
+ printk(KERN_ERR
+ "dma_calculate_descriptor_count: dmacHw_calculateDescriptorCount failed\n");
+ return -EINVAL;
+ }
+
+ return numDescriptors;
+}
+
+EXPORT_SYMBOL(dma_calculate_descriptor_count);
+
+/****************************************************************************/
+/**
+* Adds a region of memory to the descriptor ring. Note that it may take
+* multiple descriptors for each region of memory. It is the callers
+* responsibility to allocate a sufficiently large descriptor ring.
+*
+* @return
+* 0 Descriptors were added successfully
+* -ENODEV Device handed in is invalid.
+* -EINVAL Invalid parameters
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_add_descriptors(DMA_DescriptorRing_t *ring, /* Descriptor ring to add descriptors to */
+ DMA_Device_t device, /* DMA Device that descriptors are for */
+ dma_addr_t srcData, /* Place to get data (memory or device) */
+ dma_addr_t dstData, /* Place to put data (memory or device) */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ ) {
+ int rc;
+ DMA_DeviceAttribute_t *devAttr;
+
+ if (!IsDeviceValid(device)) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[device];
+
+ rc = dmacHw_setDataDescriptor(&devAttr->config,
+ ring->virtAddr,
+ (void *)srcData,
+ (void *)dstData, numBytes);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "dma_add_descriptors: dmacHw_setDataDescriptor failed with code: %d\n",
+ rc);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_add_descriptors);
+
+/****************************************************************************/
+/**
+* Sets the descriptor ring associated with a device.
+*
+* Once set, the descriptor ring will be associated with the device, even
+* across channel request/free calls. Passing in a NULL descriptor ring
+* will release any descriptor ring currently associated with the device.
+*
+* Note: If you call dma_transfer, or one of the other dma_alloc_ functions
+* the descriptor ring may be released and reallocated.
+*
+* Note: This function will release the descriptor memory for any current
+* descriptor ring associated with this device.
+*
+* @return
+* 0 Descriptors were added successfully
+* -ENODEV Device handed in is invalid.
+*/
+/****************************************************************************/
+
+int dma_set_device_descriptor_ring(DMA_Device_t device, /* Device to update the descriptor ring for. */
+ DMA_DescriptorRing_t *ring /* Descriptor ring to add descriptors to */
+ ) {
+ DMA_DeviceAttribute_t *devAttr;
+
+ if (!IsDeviceValid(device)) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[device];
+
+ /* Free the previously allocated descriptor ring */
+
+ dma_free_descriptor_ring(&devAttr->ring);
+
+ if (ring != NULL) {
+ /* Copy in the new one */
+
+ devAttr->ring = *ring;
+ }
+
+ /* Set things up so that if dma_transfer is called then this descriptor */
+ /* ring will get freed. */
+
+ devAttr->prevSrcData = 0;
+ devAttr->prevDstData = 0;
+ devAttr->prevNumBytes = 0;
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_set_device_descriptor_ring);
+
+/****************************************************************************/
+/**
+* Retrieves the descriptor ring associated with a device.
+*
+* @return
+* 0 Descriptors were added successfully
+* -ENODEV Device handed in is invalid.
+*/
+/****************************************************************************/
+
+int dma_get_device_descriptor_ring(DMA_Device_t device, /* Device to retrieve the descriptor ring for. */
+ DMA_DescriptorRing_t *ring /* Place to store retrieved ring */
+ ) {
+ DMA_DeviceAttribute_t *devAttr;
+
+ memset(ring, 0, sizeof(*ring));
+
+ if (!IsDeviceValid(device)) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[device];
+
+ *ring = devAttr->ring;
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_get_device_descriptor_ring);
+
+/****************************************************************************/
+/**
+* Configures a DMA channel.
+*
+* @return
+* >= 0 - Initialization was successfull.
+*
+* -EBUSY - Device is currently being used.
+* -ENODEV - Device handed in is invalid.
+*/
+/****************************************************************************/
+
+static int ConfigChannel(DMA_Handle_t handle)
+{
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+ int controllerIdx;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+ controllerIdx = CONTROLLER_FROM_HANDLE(handle);
+
+ if ((devAttr->flags & DMA_DEVICE_FLAG_PORT_PER_DMAC) != 0) {
+ if (devAttr->config.transferType ==
+ dmacHw_TRANSFER_TYPE_MEM_TO_PERIPHERAL) {
+ devAttr->config.dstPeripheralPort =
+ devAttr->dmacPort[controllerIdx];
+ } else if (devAttr->config.transferType ==
+ dmacHw_TRANSFER_TYPE_PERIPHERAL_TO_MEM) {
+ devAttr->config.srcPeripheralPort =
+ devAttr->dmacPort[controllerIdx];
+ }
+ }
+
+ if (dmacHw_configChannel(channel->dmacHwHandle, &devAttr->config) != 0) {
+ printk(KERN_ERR "ConfigChannel: dmacHw_configChannel failed\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+/****************************************************************************/
+/**
+* Intializes all of the data structures associated with the DMA.
+* @return
+* >= 0 - Initialization was successfull.
+*
+* -EBUSY - Device is currently being used.
+* -ENODEV - Device handed in is invalid.
+*/
+/****************************************************************************/
+
+int dma_init(void)
+{
+ int rc = 0;
+ int controllerIdx;
+ int channelIdx;
+ DMA_Device_t devIdx;
+ DMA_Channel_t *channel;
+ DMA_Handle_t dedicatedHandle;
+
+ memset(&gDMA, 0, sizeof(gDMA));
+
+ init_MUTEX_LOCKED(&gDMA.lock);
+ init_waitqueue_head(&gDMA.freeChannelQ);
+
+ /* Initialize the Hardware */
+
+ dmacHw_initDma();
+
+ /* Start off by marking all of the DMA channels as shared. */
+
+ for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
+ controllerIdx++) {
+ for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
+ channelIdx++) {
+ channel =
+ &gDMA.controller[controllerIdx].channel[channelIdx];
+
+ channel->flags = 0;
+ channel->devType = DMA_DEVICE_NONE;
+ channel->lastDevType = DMA_DEVICE_NONE;
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+ channel->fileName = "";
+ channel->lineNum = 0;
+#endif
+
+ channel->dmacHwHandle =
+ dmacHw_getChannelHandle(dmacHw_MAKE_CHANNEL_ID
+ (controllerIdx,
+ channelIdx));
+ dmacHw_initChannel(channel->dmacHwHandle);
+ }
+ }
+
+ /* Record any special attributes that channels may have */
+
+ gDMA.controller[0].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
+ gDMA.controller[0].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
+ gDMA.controller[1].channel[0].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
+ gDMA.controller[1].channel[1].flags |= DMA_CHANNEL_FLAG_LARGE_FIFO;
+
+ /* Now walk through and record the dedicated channels. */
+
+ for (devIdx = 0; devIdx < DMA_NUM_DEVICE_ENTRIES; devIdx++) {
+ DMA_DeviceAttribute_t *devAttr = &DMA_gDeviceAttribute[devIdx];
+
+ if (((devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) != 0)
+ && ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0)) {
+ printk(KERN_ERR
+ "DMA Device: %s Can only request NO_ISR for dedicated devices\n",
+ devAttr->name);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
+ /* This is a dedicated device. Mark the channel as being reserved. */
+
+ if (devAttr->dedicatedController >= DMA_NUM_CONTROLLERS) {
+ printk(KERN_ERR
+ "DMA Device: %s DMA Controller %d is out of range\n",
+ devAttr->name,
+ devAttr->dedicatedController);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ if (devAttr->dedicatedChannel >= DMA_NUM_CHANNELS) {
+ printk(KERN_ERR
+ "DMA Device: %s DMA Channel %d is out of range\n",
+ devAttr->name,
+ devAttr->dedicatedChannel);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ dedicatedHandle =
+ MAKE_HANDLE(devAttr->dedicatedController,
+ devAttr->dedicatedChannel);
+ channel = HandleToChannel(dedicatedHandle);
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) !=
+ 0) {
+ printk
+ ("DMA Device: %s attempting to use same DMA Controller:Channel (%d:%d) as %s\n",
+ devAttr->name,
+ devAttr->dedicatedController,
+ devAttr->dedicatedChannel,
+ DMA_gDeviceAttribute[channel->devType].
+ name);
+ rc = -EBUSY;
+ goto out;
+ }
+
+ channel->flags |= DMA_CHANNEL_FLAG_IS_DEDICATED;
+ channel->devType = devIdx;
+
+ if (devAttr->flags & DMA_DEVICE_FLAG_NO_ISR) {
+ channel->flags |= DMA_CHANNEL_FLAG_NO_ISR;
+ }
+
+ /* For dedicated channels, we can go ahead and configure the DMA channel now */
+ /* as well. */
+
+ ConfigChannel(dedicatedHandle);
+ }
+ }
+
+ /* Go through and register the interrupt handlers */
+
+ for (controllerIdx = 0; controllerIdx < DMA_NUM_CONTROLLERS;
+ controllerIdx++) {
+ for (channelIdx = 0; channelIdx < DMA_NUM_CHANNELS;
+ channelIdx++) {
+ channel =
+ &gDMA.controller[controllerIdx].channel[channelIdx];
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_NO_ISR) == 0) {
+ snprintf(channel->name, sizeof(channel->name),
+ "dma %d:%d %s", controllerIdx,
+ channelIdx,
+ channel->devType ==
+ DMA_DEVICE_NONE ? "" :
+ DMA_gDeviceAttribute[channel->devType].
+ name);
+
+ rc =
+ request_irq(IRQ_DMA0C0 +
+ (controllerIdx *
+ DMA_NUM_CHANNELS) +
+ channelIdx,
+ dma_interrupt_handler,
+ IRQF_DISABLED, channel->name,
+ channel);
+ if (rc != 0) {
+ printk(KERN_ERR
+ "request_irq for IRQ_DMA%dC%d failed\n",
+ controllerIdx, channelIdx);
+ }
+ }
+ }
+ }
+
+ /* Create /proc/dma/channels and /proc/dma/devices */
+
+ gDmaDir = create_proc_entry("dma", S_IFDIR | S_IRUGO | S_IXUGO, NULL);
+
+ if (gDmaDir == NULL) {
+ printk(KERN_ERR "Unable to create /proc/dma\n");
+ } else {
+ create_proc_read_entry("channels", 0, gDmaDir,
+ dma_proc_read_channels, NULL);
+ create_proc_read_entry("devices", 0, gDmaDir,
+ dma_proc_read_devices, NULL);
+ create_proc_read_entry("mem-type", 0, gDmaDir,
+ dma_proc_read_mem_type, NULL);
+ }
+
+out:
+
+ up(&gDMA.lock);
+
+ return rc;
+}
+
+/****************************************************************************/
+/**
+* Reserves a channel for use with @a dev. If the device is setup to use
+* a shared channel, then this function will block until a free channel
+* becomes available.
+*
+* @return
+* >= 0 - A valid DMA Handle.
+* -EBUSY - Device is currently being used.
+* -ENODEV - Device handed in is invalid.
+*/
+/****************************************************************************/
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+DMA_Handle_t dma_request_channel_dbg
+ (DMA_Device_t dev, const char *fileName, int lineNum)
+#else
+DMA_Handle_t dma_request_channel(DMA_Device_t dev)
+#endif
+{
+ DMA_Handle_t handle;
+ DMA_DeviceAttribute_t *devAttr;
+ DMA_Channel_t *channel;
+ int controllerIdx;
+ int controllerIdx2;
+ int channelIdx;
+
+ if (down_interruptible(&gDMA.lock) < 0) {
+ return -ERESTARTSYS;
+ }
+
+ if ((dev < 0) || (dev >= DMA_NUM_DEVICE_ENTRIES)) {
+ handle = -ENODEV;
+ goto out;
+ }
+ devAttr = &DMA_gDeviceAttribute[dev];
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+ {
+ char *s;
+
+ s = strrchr(fileName, '/');
+ if (s != NULL) {
+ fileName = s + 1;
+ }
+ }
+#endif
+ if ((devAttr->flags & DMA_DEVICE_FLAG_IN_USE) != 0) {
+ /* This device has already been requested and not been freed */
+
+ printk(KERN_ERR "%s: device %s is already requested\n",
+ __func__, devAttr->name);
+ handle = -EBUSY;
+ goto out;
+ }
+
+ if ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) != 0) {
+ /* This device has a dedicated channel. */
+
+ channel =
+ &gDMA.controller[devAttr->dedicatedController].
+ channel[devAttr->dedicatedChannel];
+ if ((channel->flags & DMA_CHANNEL_FLAG_IN_USE) != 0) {
+ handle = -EBUSY;
+ goto out;
+ }
+
+ channel->flags |= DMA_CHANNEL_FLAG_IN_USE;
+ devAttr->flags |= DMA_DEVICE_FLAG_IN_USE;
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+ channel->fileName = fileName;
+ channel->lineNum = lineNum;
+#endif
+ handle =
+ MAKE_HANDLE(devAttr->dedicatedController,
+ devAttr->dedicatedChannel);
+ goto out;
+ }
+
+ /* This device needs to use one of the shared channels. */
+
+ handle = DMA_INVALID_HANDLE;
+ while (handle == DMA_INVALID_HANDLE) {
+ /* Scan through the shared channels and see if one is available */
+
+ for (controllerIdx2 = 0; controllerIdx2 < DMA_NUM_CONTROLLERS;
+ controllerIdx2++) {
+ /* Check to see if we should try on controller 1 first. */
+
+ controllerIdx = controllerIdx2;
+ if ((devAttr->
+ flags & DMA_DEVICE_FLAG_ALLOC_DMA1_FIRST) != 0) {
+ controllerIdx = 1 - controllerIdx;
+ }
+
+ /* See if the device is available on the controller being tested */
+
+ if ((devAttr->
+ flags & (DMA_DEVICE_FLAG_ON_DMA0 << controllerIdx))
+ != 0) {
+ for (channelIdx = 0;
+ channelIdx < DMA_NUM_CHANNELS;
+ channelIdx++) {
+ channel =
+ &gDMA.controller[controllerIdx].
+ channel[channelIdx];
+
+ if (((channel->
+ flags &
+ DMA_CHANNEL_FLAG_IS_DEDICATED) ==
+ 0)
+ &&
+ ((channel->
+ flags & DMA_CHANNEL_FLAG_IN_USE)
+ == 0)) {
+ if (((channel->
+ flags &
+ DMA_CHANNEL_FLAG_LARGE_FIFO)
+ != 0)
+ &&
+ ((devAttr->
+ flags &
+ DMA_DEVICE_FLAG_ALLOW_LARGE_FIFO)
+ == 0)) {
+ /* This channel is a large fifo - don't tie it up */
+ /* with devices that we don't want using it. */
+
+ continue;
+ }
+
+ channel->flags |=
+ DMA_CHANNEL_FLAG_IN_USE;
+ channel->devType = dev;
+ devAttr->flags |=
+ DMA_DEVICE_FLAG_IN_USE;
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+ channel->fileName = fileName;
+ channel->lineNum = lineNum;
+#endif
+ handle =
+ MAKE_HANDLE(controllerIdx,
+ channelIdx);
+
+ /* Now that we've reserved the channel - we can go ahead and configure it */
+
+ if (ConfigChannel(handle) != 0) {
+ handle = -EIO;
+ printk(KERN_ERR
+ "dma_request_channel: ConfigChannel failed\n");
+ }
+ goto out;
+ }
+ }
+ }
+ }
+
+ /* No channels are currently available. Let's wait for one to free up. */
+
+ {
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(&gDMA.freeChannelQ, &wait,
+ TASK_INTERRUPTIBLE);
+ up(&gDMA.lock);
+ schedule();
+ finish_wait(&gDMA.freeChannelQ, &wait);
+
+ if (signal_pending(current)) {
+ /* We don't currently hold gDMA.lock, so we return directly */
+
+ return -ERESTARTSYS;
+ }
+ }
+
+ if (down_interruptible(&gDMA.lock)) {
+ return -ERESTARTSYS;
+ }
+ }
+
+out:
+ up(&gDMA.lock);
+
+ return handle;
+}
+
+/* Create both _dbg and non _dbg functions for modules. */
+
+#if (DMA_DEBUG_TRACK_RESERVATION)
+#undef dma_request_channel
+DMA_Handle_t dma_request_channel(DMA_Device_t dev)
+{
+ return dma_request_channel_dbg(dev, __FILE__, __LINE__);
+}
+
+EXPORT_SYMBOL(dma_request_channel_dbg);
+#endif
+EXPORT_SYMBOL(dma_request_channel);
+
+/****************************************************************************/
+/**
+* Frees a previously allocated DMA Handle.
+*/
+/****************************************************************************/
+
+int dma_free_channel(DMA_Handle_t handle /* DMA handle. */
+ ) {
+ int rc = 0;
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+
+ if (down_interruptible(&gDMA.lock) < 0) {
+ return -ERESTARTSYS;
+ }
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+
+ if ((channel->flags & DMA_CHANNEL_FLAG_IS_DEDICATED) == 0) {
+ channel->lastDevType = channel->devType;
+ channel->devType = DMA_DEVICE_NONE;
+ }
+ channel->flags &= ~DMA_CHANNEL_FLAG_IN_USE;
+ devAttr->flags &= ~DMA_DEVICE_FLAG_IN_USE;
+
+out:
+ up(&gDMA.lock);
+
+ wake_up_interruptible(&gDMA.freeChannelQ);
+
+ return rc;
+}
+
+EXPORT_SYMBOL(dma_free_channel);
+
+/****************************************************************************/
+/**
+* Determines if a given device has been configured as using a shared
+* channel.
+*
+* @return
+* 0 Device uses a dedicated channel
+* > zero Device uses a shared channel
+* < zero Error code
+*/
+/****************************************************************************/
+
+int dma_device_is_channel_shared(DMA_Device_t device /* Device to check. */
+ ) {
+ DMA_DeviceAttribute_t *devAttr;
+
+ if (!IsDeviceValid(device)) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[device];
+
+ return ((devAttr->flags & DMA_DEVICE_FLAG_IS_DEDICATED) == 0);
+}
+
+EXPORT_SYMBOL(dma_device_is_channel_shared);
+
+/****************************************************************************/
+/**
+* Allocates buffers for the descriptors. This is normally done automatically
+* but needs to be done explicitly when initiating a dma from interrupt
+* context.
+*
+* @return
+* 0 Descriptors were allocated successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_alloc_descriptors(DMA_Handle_t handle, /* DMA Handle */
+ dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
+ dma_addr_t srcData, /* Place to get data to write to device */
+ dma_addr_t dstData, /* Pointer to device data address */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ ) {
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+ int numDescriptors;
+ size_t ringBytesRequired;
+ int rc = 0;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+
+ if (devAttr->config.transferType != transferType) {
+ return -EINVAL;
+ }
+
+ /* Figure out how many descriptors we need. */
+
+ /* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
+ /* srcData, dstData, numBytes); */
+
+ numDescriptors = dmacHw_calculateDescriptorCount(&devAttr->config,
+ (void *)srcData,
+ (void *)dstData,
+ numBytes);
+ if (numDescriptors < 0) {
+ printk(KERN_ERR "%s: dmacHw_calculateDescriptorCount failed\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ /* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
+ /* a new one. */
+
+ ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
+
+ /* printk("ringBytesRequired: %d\n", ringBytesRequired); */
+
+ if (ringBytesRequired > devAttr->ring.bytesAllocated) {
+ /* Make sure that this code path is never taken from interrupt context. */
+ /* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
+ /* allocation needs to have already been done. */
+
+ might_sleep();
+
+ /* Free the old descriptor ring and allocate a new one. */
+
+ dma_free_descriptor_ring(&devAttr->ring);
+
+ /* And allocate a new one. */
+
+ rc =
+ dma_alloc_descriptor_ring(&devAttr->ring,
+ numDescriptors);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "%s: dma_alloc_descriptor_ring(%d) failed\n",
+ __func__, numDescriptors);
+ return rc;
+ }
+ /* Setup the descriptor for this transfer */
+
+ if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
+ devAttr->ring.physAddr,
+ devAttr->ring.bytesAllocated,
+ numDescriptors) < 0) {
+ printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n",
+ __func__);
+ return -EINVAL;
+ }
+ } else {
+ /* We've already got enough ring buffer allocated. All we need to do is reset */
+ /* any control information, just in case the previous DMA was stopped. */
+
+ dmacHw_resetDescriptorControl(devAttr->ring.virtAddr);
+ }
+
+ /* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
+ /* as last time, then we don't need to call setDataDescriptor again. */
+
+ if (dmacHw_setDataDescriptor(&devAttr->config,
+ devAttr->ring.virtAddr,
+ (void *)srcData,
+ (void *)dstData, numBytes) < 0) {
+ printk(KERN_ERR "%s: dmacHw_setDataDescriptor failed\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ /* Remember the critical information for this transfer so that we can eliminate */
+ /* another call to dma_alloc_descriptors if the caller reuses the same buffers */
+
+ devAttr->prevSrcData = srcData;
+ devAttr->prevDstData = dstData;
+ devAttr->prevNumBytes = numBytes;
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_alloc_descriptors);
+
+/****************************************************************************/
+/**
+* Allocates and sets up descriptors for a double buffered circular buffer.
+*
+* This is primarily intended to be used for things like the ingress samples
+* from a microphone.
+*
+* @return
+* > 0 Number of descriptors actually allocated.
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _MEM_TO_DEV and not _DEV_TO_MEM)
+* -ENOMEM Memory exhausted
+*/
+/****************************************************************************/
+
+int dma_alloc_double_dst_descriptors(DMA_Handle_t handle, /* DMA Handle */
+ dma_addr_t srcData, /* Physical address of source data */
+ dma_addr_t dstData1, /* Physical address of first destination buffer */
+ dma_addr_t dstData2, /* Physical address of second destination buffer */
+ size_t numBytes /* Number of bytes in each destination buffer */
+ ) {
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+ int numDst1Descriptors;
+ int numDst2Descriptors;
+ int numDescriptors;
+ size_t ringBytesRequired;
+ int rc = 0;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+
+ /* Figure out how many descriptors we need. */
+
+ /* printk("srcData: 0x%08x dstData: 0x%08x, numBytes: %d\n", */
+ /* srcData, dstData, numBytes); */
+
+ numDst1Descriptors =
+ dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
+ (void *)dstData1, numBytes);
+ if (numDst1Descriptors < 0) {
+ return -EINVAL;
+ }
+ numDst2Descriptors =
+ dmacHw_calculateDescriptorCount(&devAttr->config, (void *)srcData,
+ (void *)dstData2, numBytes);
+ if (numDst2Descriptors < 0) {
+ return -EINVAL;
+ }
+ numDescriptors = numDst1Descriptors + numDst2Descriptors;
+ /* printk("numDescriptors: %d\n", numDescriptors); */
+
+ /* Check to see if we can reuse the existing descriptor ring, or if we need to allocate */
+ /* a new one. */
+
+ ringBytesRequired = dmacHw_descriptorLen(numDescriptors);
+
+ /* printk("ringBytesRequired: %d\n", ringBytesRequired); */
+
+ if (ringBytesRequired > devAttr->ring.bytesAllocated) {
+ /* Make sure that this code path is never taken from interrupt context. */
+ /* It's OK for an interrupt to initiate a DMA transfer, but the descriptor */
+ /* allocation needs to have already been done. */
+
+ might_sleep();
+
+ /* Free the old descriptor ring and allocate a new one. */
+
+ dma_free_descriptor_ring(&devAttr->ring);
+
+ /* And allocate a new one. */
+
+ rc =
+ dma_alloc_descriptor_ring(&devAttr->ring,
+ numDescriptors);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "%s: dma_alloc_descriptor_ring(%d) failed\n",
+ __func__, ringBytesRequired);
+ return rc;
+ }
+ }
+
+ /* Setup the descriptor for this transfer. Since this function is used with */
+ /* CONTINUOUS DMA operations, we need to reinitialize every time, otherwise */
+ /* setDataDescriptor will keep trying to append onto the end. */
+
+ if (dmacHw_initDescriptor(devAttr->ring.virtAddr,
+ devAttr->ring.physAddr,
+ devAttr->ring.bytesAllocated,
+ numDescriptors) < 0) {
+ printk(KERN_ERR "%s: dmacHw_initDescriptor failed\n", __func__);
+ return -EINVAL;
+ }
+
+ /* dma_alloc/free both set the prevSrc/DstData to 0. If they happen to be the same */
+ /* as last time, then we don't need to call setDataDescriptor again. */
+
+ if (dmacHw_setDataDescriptor(&devAttr->config,
+ devAttr->ring.virtAddr,
+ (void *)srcData,
+ (void *)dstData1, numBytes) < 0) {
+ printk(KERN_ERR "%s: dmacHw_setDataDescriptor 1 failed\n",
+ __func__);
+ return -EINVAL;
+ }
+ if (dmacHw_setDataDescriptor(&devAttr->config,
+ devAttr->ring.virtAddr,
+ (void *)srcData,
+ (void *)dstData2, numBytes) < 0) {
+ printk(KERN_ERR "%s: dmacHw_setDataDescriptor 2 failed\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ /* You should use dma_start_transfer rather than dma_transfer_xxx so we don't */
+ /* try to make the 'prev' variables right. */
+
+ devAttr->prevSrcData = 0;
+ devAttr->prevDstData = 0;
+ devAttr->prevNumBytes = 0;
+
+ return numDescriptors;
+}
+
+EXPORT_SYMBOL(dma_alloc_double_dst_descriptors);
+
+/****************************************************************************/
+/**
+* Initiates a transfer when the descriptors have already been setup.
+*
+* This is a special case, and normally, the dma_transfer_xxx functions should
+* be used.
+*
+* @return
+* 0 Transfer was started successfully
+* -ENODEV Invalid handle
+*/
+/****************************************************************************/
+
+int dma_start_transfer(DMA_Handle_t handle)
+{
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+
+ dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
+ devAttr->ring.virtAddr);
+
+ /* Since we got this far, everything went successfully */
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_start_transfer);
+
+/****************************************************************************/
+/**
+* Stops a previously started DMA transfer.
+*
+* @return
+* 0 Transfer was stopped successfully
+* -ENODEV Invalid handle
+*/
+/****************************************************************************/
+
+int dma_stop_transfer(DMA_Handle_t handle)
+{
+ DMA_Channel_t *channel;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+
+ dmacHw_stopTransfer(channel->dmacHwHandle);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_stop_transfer);
+
+/****************************************************************************/
+/**
+* Waits for a DMA to complete by polling. This function is only intended
+* to be used for testing. Interrupts should be used for most DMA operations.
+*/
+/****************************************************************************/
+
+int dma_wait_transfer_done(DMA_Handle_t handle)
+{
+ DMA_Channel_t *channel;
+ dmacHw_TRANSFER_STATUS_e status;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+
+ while ((status =
+ dmacHw_transferCompleted(channel->dmacHwHandle)) ==
+ dmacHw_TRANSFER_STATUS_BUSY) {
+ ;
+ }
+
+ if (status == dmacHw_TRANSFER_STATUS_ERROR) {
+ printk(KERN_ERR "%s: DMA transfer failed\n", __func__);
+ return -EIO;
+ }
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_wait_transfer_done);
+
+/****************************************************************************/
+/**
+* Initiates a DMA, allocating the descriptors as required.
+*
+* @return
+* 0 Transfer was started successfully
+* -EINVAL Invalid device type for this kind of transfer
+* (i.e. the device is _DEV_TO_MEM and not _MEM_TO_DEV)
+*/
+/****************************************************************************/
+
+int dma_transfer(DMA_Handle_t handle, /* DMA Handle */
+ dmacHw_TRANSFER_TYPE_e transferType, /* Type of transfer being performed */
+ dma_addr_t srcData, /* Place to get data to write to device */
+ dma_addr_t dstData, /* Pointer to device data address */
+ size_t numBytes /* Number of bytes to transfer to the device */
+ ) {
+ DMA_Channel_t *channel;
+ DMA_DeviceAttribute_t *devAttr;
+ int rc = 0;
+
+ channel = HandleToChannel(handle);
+ if (channel == NULL) {
+ return -ENODEV;
+ }
+
+ devAttr = &DMA_gDeviceAttribute[channel->devType];
+
+ if (devAttr->config.transferType != transferType) {
+ return -EINVAL;
+ }
+
+ /* We keep track of the information about the previous request for this */
+ /* device, and if the attributes match, then we can use the descriptors we setup */
+ /* the last time, and not have to reinitialize everything. */
+
+ {
+ rc =
+ dma_alloc_descriptors(handle, transferType, srcData,
+ dstData, numBytes);
+ if (rc != 0) {
+ return rc;
+ }
+ }
+
+ /* And kick off the transfer */
+
+ devAttr->numBytes = numBytes;
+ devAttr->transferStartTime = timer_get_tick_count();
+
+ dmacHw_initiateTransfer(channel->dmacHwHandle, &devAttr->config,
+ devAttr->ring.virtAddr);
+
+ /* Since we got this far, everything went successfully */
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_transfer);
+
+/****************************************************************************/
+/**
+* Set the callback function which will be called when a transfer completes.
+* If a NULL callback function is set, then no callback will occur.
+*
+* @note @a devHandler will be called from IRQ context.
+*
+* @return
+* 0 - Success
+* -ENODEV - Device handed in is invalid.
+*/
+/****************************************************************************/
+
+int dma_set_device_handler(DMA_Device_t dev, /* Device to set the callback for. */
+ DMA_DeviceHandler_t devHandler, /* Function to call when the DMA completes */
+ void *userData /* Pointer which will be passed to devHandler. */
+ ) {
+ DMA_DeviceAttribute_t *devAttr;
+ unsigned long flags;
+
+ if (!IsDeviceValid(dev)) {
+ return -ENODEV;
+ }
+ devAttr = &DMA_gDeviceAttribute[dev];
+
+ local_irq_save(flags);
+
+ devAttr->userData = userData;
+ devAttr->devHandler = devHandler;
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_set_device_handler);
+
+/****************************************************************************/
+/**
+* Initializes a memory mapping structure
+*/
+/****************************************************************************/
+
+int dma_init_mem_map(DMA_MemMap_t *memMap)
+{
+ memset(memMap, 0, sizeof(*memMap));
+
+ init_MUTEX(&memMap->lock);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_init_mem_map);
+
+/****************************************************************************/
+/**
+* Releases any memory currently being held by a memory mapping structure.
+*/
+/****************************************************************************/
+
+int dma_term_mem_map(DMA_MemMap_t *memMap)
+{
+ down(&memMap->lock); /* Just being paranoid */
+
+ /* Free up any allocated memory */
+
+ up(&memMap->lock);
+ memset(memMap, 0, sizeof(*memMap));
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_term_mem_map);
+
+/****************************************************************************/
+/**
+* Looks at a memory address and categorizes it.
+*
+* @return One of the values from the DMA_MemType_t enumeration.
+*/
+/****************************************************************************/
+
+DMA_MemType_t dma_mem_type(void *addr)
+{
+ unsigned long addrVal = (unsigned long)addr;
+
+ if (addrVal >= VMALLOC_END) {
+ /* NOTE: DMA virtual memory space starts at 0xFFxxxxxx */
+
+ /* dma_alloc_xxx pages are physically and virtually contiguous */
+
+ return DMA_MEM_TYPE_DMA;
+ }
+
+ /* Technically, we could add one more classification. Addresses between VMALLOC_END */
+ /* and the beginning of the DMA virtual address could be considered to be I/O space. */
+ /* Right now, nobody cares about this particular classification, so we ignore it. */
+
+ if (is_vmalloc_addr(addr)) {
+ /* Address comes from the vmalloc'd region. Pages are virtually */
+ /* contiguous but NOT physically contiguous */
+
+ return DMA_MEM_TYPE_VMALLOC;
+ }
+
+ if (addrVal >= PAGE_OFFSET) {
+ /* PAGE_OFFSET is typically 0xC0000000 */
+
+ /* kmalloc'd pages are physically contiguous */
+
+ return DMA_MEM_TYPE_KMALLOC;
+ }
+
+ return DMA_MEM_TYPE_USER;
+}
+
+EXPORT_SYMBOL(dma_mem_type);
+
+/****************************************************************************/
+/**
+* Looks at a memory address and determines if we support DMA'ing to/from
+* that type of memory.
+*
+* @return boolean -
+* return value != 0 means dma supported
+* return value == 0 means dma not supported
+*/
+/****************************************************************************/
+
+int dma_mem_supports_dma(void *addr)
+{
+ DMA_MemType_t memType = dma_mem_type(addr);
+
+ return (memType == DMA_MEM_TYPE_DMA)
+#if ALLOW_MAP_OF_KMALLOC_MEMORY
+ || (memType == DMA_MEM_TYPE_KMALLOC)
+#endif
+ || (memType == DMA_MEM_TYPE_USER);
+}
+
+EXPORT_SYMBOL(dma_mem_supports_dma);
+
+/****************************************************************************/
+/**
+* Maps in a memory region such that it can be used for performing a DMA.
+*
+* @return
+*/
+/****************************************************************************/
+
+int dma_map_start(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ enum dma_data_direction dir /* Direction that the mapping will be going */
+ ) {
+ int rc;
+
+ down(&memMap->lock);
+
+ DMA_MAP_PRINT("memMap: %p\n", memMap);
+
+ if (memMap->inUse) {
+ printk(KERN_ERR "%s: memory map %p is already being used\n",
+ __func__, memMap);
+ rc = -EBUSY;
+ goto out;
+ }
+
+ memMap->inUse = 1;
+ memMap->dir = dir;
+ memMap->numRegionsUsed = 0;
+
+ rc = 0;
+
+out:
+
+ DMA_MAP_PRINT("returning %d", rc);
+
+ up(&memMap->lock);
+
+ return rc;
+}
+
+EXPORT_SYMBOL(dma_map_start);
+
+/****************************************************************************/
+/**
+* Adds a segment of memory to a memory map. Each segment is both
+* physically and virtually contiguous.
+*
+* @return 0 on success, error code otherwise.
+*/
+/****************************************************************************/
+
+static int dma_map_add_segment(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ DMA_Region_t *region, /* Region that the segment belongs to */
+ void *virtAddr, /* Virtual address of the segment being added */
+ dma_addr_t physAddr, /* Physical address of the segment being added */
+ size_t numBytes /* Number of bytes of the segment being added */
+ ) {
+ DMA_Segment_t *segment;
+
+ DMA_MAP_PRINT("memMap:%p va:%p pa:0x%x #:%d\n", memMap, virtAddr,
+ physAddr, numBytes);
+
+ /* Sanity check */
+
+ if (((unsigned long)virtAddr < (unsigned long)region->virtAddr)
+ || (((unsigned long)virtAddr + numBytes)) >
+ ((unsigned long)region->virtAddr + region->numBytes)) {
+ printk(KERN_ERR
+ "%s: virtAddr %p is outside region @ %p len: %d\n",
+ __func__, virtAddr, region->virtAddr, region->numBytes);
+ return -EINVAL;
+ }
+
+ if (region->numSegmentsUsed > 0) {
+ /* Check to see if this segment is physically contiguous with the previous one */
+
+ segment = &region->segment[region->numSegmentsUsed - 1];
+
+ if ((segment->physAddr + segment->numBytes) == physAddr) {
+ /* It is - just add on to the end */
+
+ DMA_MAP_PRINT("appending %d bytes to last segment\n",
+ numBytes);
+
+ segment->numBytes += numBytes;
+
+ return 0;
+ }
+ }
+
+ /* Reallocate to hold more segments, if required. */
+
+ if (region->numSegmentsUsed >= region->numSegmentsAllocated) {
+ DMA_Segment_t *newSegment;
+ size_t oldSize =
+ region->numSegmentsAllocated * sizeof(*newSegment);
+ int newAlloc = region->numSegmentsAllocated + 4;
+ size_t newSize = newAlloc * sizeof(*newSegment);
+
+ newSegment = kmalloc(newSize, GFP_KERNEL);
+ if (newSegment == NULL) {
+ return -ENOMEM;
+ }
+ memcpy(newSegment, region->segment, oldSize);
+ memset(&((uint8_t *) newSegment)[oldSize], 0,
+ newSize - oldSize);
+ kfree(region->segment);
+
+ region->numSegmentsAllocated = newAlloc;
+ region->segment = newSegment;
+ }
+
+ segment = &region->segment[region->numSegmentsUsed];
+ region->numSegmentsUsed++;
+
+ segment->virtAddr = virtAddr;
+ segment->physAddr = physAddr;
+ segment->numBytes = numBytes;
+
+ DMA_MAP_PRINT("returning success\n");
+
+ return 0;
+}
+
+/****************************************************************************/
+/**
+* Adds a region of memory to a memory map. Each region is virtually
+* contiguous, but not necessarily physically contiguous.
+*
+* @return 0 on success, error code otherwise.
+*/
+/****************************************************************************/
+
+int dma_map_add_region(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ void *mem, /* Virtual address that we want to get a map of */
+ size_t numBytes /* Number of bytes being mapped */
+ ) {
+ unsigned long addr = (unsigned long)mem;
+ unsigned int offset;
+ int rc = 0;
+ DMA_Region_t *region;
+ dma_addr_t physAddr;
+
+ down(&memMap->lock);
+
+ DMA_MAP_PRINT("memMap:%p va:%p #:%d\n", memMap, mem, numBytes);
+
+ if (!memMap->inUse) {
+ printk(KERN_ERR "%s: Make sure you call dma_map_start first\n",
+ __func__);
+ rc = -EINVAL;
+ goto out;
+ }
+
+ /* Reallocate to hold more regions. */
+
+ if (memMap->numRegionsUsed >= memMap->numRegionsAllocated) {
+ DMA_Region_t *newRegion;
+ size_t oldSize =
+ memMap->numRegionsAllocated * sizeof(*newRegion);
+ int newAlloc = memMap->numRegionsAllocated + 4;
+ size_t newSize = newAlloc * sizeof(*newRegion);
+
+ newRegion = kmalloc(newSize, GFP_KERNEL);
+ if (newRegion == NULL) {
+ rc = -ENOMEM;
+ goto out;
+ }
+ memcpy(newRegion, memMap->region, oldSize);
+ memset(&((uint8_t *) newRegion)[oldSize], 0, newSize - oldSize);
+
+ kfree(memMap->region);
+
+ memMap->numRegionsAllocated = newAlloc;
+ memMap->region = newRegion;
+ }
+
+ region = &memMap->region[memMap->numRegionsUsed];
+ memMap->numRegionsUsed++;
+
+ offset = addr & ~PAGE_MASK;
+
+ region->memType = dma_mem_type(mem);
+ region->virtAddr = mem;
+ region->numBytes = numBytes;
+ region->numSegmentsUsed = 0;
+ region->numLockedPages = 0;
+ region->lockedPages = NULL;
+
+ switch (region->memType) {
+ case DMA_MEM_TYPE_VMALLOC:
+ {
+ atomic_inc(&gDmaStatMemTypeVmalloc);
+
+ /* printk(KERN_ERR "%s: vmalloc'd pages are not supported\n", __func__); */
+
+ /* vmalloc'd pages are not physically contiguous */
+
+ rc = -EINVAL;
+ break;
+ }
+
+ case DMA_MEM_TYPE_KMALLOC:
+ {
+ atomic_inc(&gDmaStatMemTypeKmalloc);
+
+ /* kmalloc'd pages are physically contiguous, so they'll have exactly */
+ /* one segment */
+
+#if ALLOW_MAP_OF_KMALLOC_MEMORY
+ physAddr =
+ dma_map_single(NULL, mem, numBytes, memMap->dir);
+ rc = dma_map_add_segment(memMap, region, mem, physAddr,
+ numBytes);
+#else
+ rc = -EINVAL;
+#endif
+ break;
+ }
+
+ case DMA_MEM_TYPE_DMA:
+ {
+ /* dma_alloc_xxx pages are physically contiguous */
+
+ atomic_inc(&gDmaStatMemTypeCoherent);
+
+ physAddr = (vmalloc_to_pfn(mem) << PAGE_SHIFT) + offset;
+
+ dma_sync_single_for_cpu(NULL, physAddr, numBytes,
+ memMap->dir);
+ rc = dma_map_add_segment(memMap, region, mem, physAddr,
+ numBytes);
+ break;
+ }
+
+ case DMA_MEM_TYPE_USER:
+ {
+ size_t firstPageOffset;
+ size_t firstPageSize;
+ struct page **pages;
+ struct task_struct *userTask;
+
+ atomic_inc(&gDmaStatMemTypeUser);
+
+#if 1
+ /* If the pages are user pages, then the dma_mem_map_set_user_task function */
+ /* must have been previously called. */
+
+ if (memMap->userTask == NULL) {
+ printk(KERN_ERR
+ "%s: must call dma_mem_map_set_user_task when using user-mode memory\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ /* User pages need to be locked. */
+
+ firstPageOffset =
+ (unsigned long)region->virtAddr & (PAGE_SIZE - 1);
+ firstPageSize = PAGE_SIZE - firstPageOffset;
+
+ region->numLockedPages = (firstPageOffset
+ + region->numBytes +
+ PAGE_SIZE - 1) / PAGE_SIZE;
+ pages =
+ kmalloc(region->numLockedPages *
+ sizeof(struct page *), GFP_KERNEL);
+
+ if (pages == NULL) {
+ region->numLockedPages = 0;
+ return -ENOMEM;
+ }
+
+ userTask = memMap->userTask;
+
+ down_read(&userTask->mm->mmap_sem);
+ rc = get_user_pages(userTask, /* task */
+ userTask->mm, /* mm */
+ (unsigned long)region->virtAddr, /* start */
+ region->numLockedPages, /* len */
+ memMap->dir == DMA_FROM_DEVICE, /* write */
+ 0, /* force */
+ pages, /* pages (array of pointers to page) */
+ NULL); /* vmas */
+ up_read(&userTask->mm->mmap_sem);
+
+ if (rc != region->numLockedPages) {
+ kfree(pages);
+ region->numLockedPages = 0;
+
+ if (rc >= 0) {
+ rc = -EINVAL;
+ }
+ } else {
+ uint8_t *virtAddr = region->virtAddr;
+ size_t bytesRemaining;
+ int pageIdx;
+
+ rc = 0; /* Since get_user_pages returns +ve number */
+
+ region->lockedPages = pages;
+
+ /* We've locked the user pages. Now we need to walk them and figure */
+ /* out the physical addresses. */
+
+ /* The first page may be partial */
+
+ dma_map_add_segment(memMap,
+ region,
+ virtAddr,
+ PFN_PHYS(page_to_pfn
+ (pages[0])) +
+ firstPageOffset,
+ firstPageSize);
+
+ virtAddr += firstPageSize;
+ bytesRemaining =
+ region->numBytes - firstPageSize;
+
+ for (pageIdx = 1;
+ pageIdx < region->numLockedPages;
+ pageIdx++) {
+ size_t bytesThisPage =
+ (bytesRemaining >
+ PAGE_SIZE ? PAGE_SIZE :
+ bytesRemaining);
+
+ DMA_MAP_PRINT
+ ("pageIdx:%d pages[pageIdx]=%p pfn=%u phys=%u\n",
+ pageIdx, pages[pageIdx],
+ page_to_pfn(pages[pageIdx]),
+ PFN_PHYS(page_to_pfn
+ (pages[pageIdx])));
+
+ dma_map_add_segment(memMap,
+ region,
+ virtAddr,
+ PFN_PHYS(page_to_pfn
+ (pages
+ [pageIdx])),
+ bytesThisPage);
+
+ virtAddr += bytesThisPage;
+ bytesRemaining -= bytesThisPage;
+ }
+ }
+#else
+ printk(KERN_ERR
+ "%s: User mode pages are not yet supported\n",
+ __func__);
+
+ /* user pages are not physically contiguous */
+
+ rc = -EINVAL;
+#endif
+ break;
+ }
+
+ default:
+ {
+ printk(KERN_ERR "%s: Unsupported memory type: %d\n",
+ __func__, region->memType);
+
+ rc = -EINVAL;
+ break;
+ }
+ }
+
+ if (rc != 0) {
+ memMap->numRegionsUsed--;
+ }
+
+out:
+
+ DMA_MAP_PRINT("returning %d\n", rc);
+
+ up(&memMap->lock);
+
+ return rc;
+}
+
+EXPORT_SYMBOL(dma_map_add_segment);
+
+/****************************************************************************/
+/**
+* Maps in a memory region such that it can be used for performing a DMA.
+*
+* @return 0 on success, error code otherwise.
+*/
+/****************************************************************************/
+
+int dma_map_mem(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ void *mem, /* Virtual address that we want to get a map of */
+ size_t numBytes, /* Number of bytes being mapped */
+ enum dma_data_direction dir /* Direction that the mapping will be going */
+ ) {
+ int rc;
+
+ rc = dma_map_start(memMap, dir);
+ if (rc == 0) {
+ rc = dma_map_add_region(memMap, mem, numBytes);
+ if (rc < 0) {
+ /* Since the add fails, this function will fail, and the caller won't */
+ /* call unmap, so we need to do it here. */
+
+ dma_unmap(memMap, 0);
+ }
+ }
+
+ return rc;
+}
+
+EXPORT_SYMBOL(dma_map_mem);
+
+/****************************************************************************/
+/**
+* Setup a descriptor ring for a given memory map.
+*
+* It is assumed that the descriptor ring has already been initialized, and
+* this routine will only reallocate a new descriptor ring if the existing
+* one is too small.
+*
+* @return 0 on success, error code otherwise.
+*/
+/****************************************************************************/
+
+int dma_map_create_descriptor_ring(DMA_Device_t dev, /* DMA device (where the ring is stored) */
+ DMA_MemMap_t *memMap, /* Memory map that will be used */
+ dma_addr_t devPhysAddr /* Physical address of device */
+ ) {
+ int rc;
+ int numDescriptors;
+ DMA_DeviceAttribute_t *devAttr;
+ DMA_Region_t *region;
+ DMA_Segment_t *segment;
+ dma_addr_t srcPhysAddr;
+ dma_addr_t dstPhysAddr;
+ int regionIdx;
+ int segmentIdx;
+
+ devAttr = &DMA_gDeviceAttribute[dev];
+
+ down(&memMap->lock);
+
+ /* Figure out how many descriptors we need */
+
+ numDescriptors = 0;
+ for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
+ region = &memMap->region[regionIdx];
+
+ for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
+ segmentIdx++) {
+ segment = &region->segment[segmentIdx];
+
+ if (memMap->dir == DMA_TO_DEVICE) {
+ srcPhysAddr = segment->physAddr;
+ dstPhysAddr = devPhysAddr;
+ } else {
+ srcPhysAddr = devPhysAddr;
+ dstPhysAddr = segment->physAddr;
+ }
+
+ rc =
+ dma_calculate_descriptor_count(dev, srcPhysAddr,
+ dstPhysAddr,
+ segment->
+ numBytes);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "%s: dma_calculate_descriptor_count failed: %d\n",
+ __func__, rc);
+ goto out;
+ }
+ numDescriptors += rc;
+ }
+ }
+
+ /* Adjust the size of the ring, if it isn't big enough */
+
+ if (numDescriptors > devAttr->ring.descriptorsAllocated) {
+ dma_free_descriptor_ring(&devAttr->ring);
+ rc =
+ dma_alloc_descriptor_ring(&devAttr->ring,
+ numDescriptors);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "%s: dma_alloc_descriptor_ring failed: %d\n",
+ __func__, rc);
+ goto out;
+ }
+ } else {
+ rc =
+ dma_init_descriptor_ring(&devAttr->ring,
+ numDescriptors);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "%s: dma_init_descriptor_ring failed: %d\n",
+ __func__, rc);
+ goto out;
+ }
+ }
+
+ /* Populate the descriptors */
+
+ for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
+ region = &memMap->region[regionIdx];
+
+ for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
+ segmentIdx++) {
+ segment = &region->segment[segmentIdx];
+
+ if (memMap->dir == DMA_TO_DEVICE) {
+ srcPhysAddr = segment->physAddr;
+ dstPhysAddr = devPhysAddr;
+ } else {
+ srcPhysAddr = devPhysAddr;
+ dstPhysAddr = segment->physAddr;
+ }
+
+ rc =
+ dma_add_descriptors(&devAttr->ring, dev,
+ srcPhysAddr, dstPhysAddr,
+ segment->numBytes);
+ if (rc < 0) {
+ printk(KERN_ERR
+ "%s: dma_add_descriptors failed: %d\n",
+ __func__, rc);
+ goto out;
+ }
+ }
+ }
+
+ rc = 0;
+
+out:
+
+ up(&memMap->lock);
+ return rc;
+}
+
+EXPORT_SYMBOL(dma_map_create_descriptor_ring);
+
+/****************************************************************************/
+/**
+* Maps in a memory region such that it can be used for performing a DMA.
+*
+* @return
+*/
+/****************************************************************************/
+
+int dma_unmap(DMA_MemMap_t *memMap, /* Stores state information about the map */
+ int dirtied /* non-zero if any of the pages were modified */
+ ) {
+ int regionIdx;
+ int segmentIdx;
+ DMA_Region_t *region;
+ DMA_Segment_t *segment;
+
+ for (regionIdx = 0; regionIdx < memMap->numRegionsUsed; regionIdx++) {
+ region = &memMap->region[regionIdx];
+
+ for (segmentIdx = 0; segmentIdx < region->numSegmentsUsed;
+ segmentIdx++) {
+ segment = &region->segment[segmentIdx];
+
+ switch (region->memType) {
+ case DMA_MEM_TYPE_VMALLOC:
+ {
+ printk(KERN_ERR
+ "%s: vmalloc'd pages are not yet supported\n",
+ __func__);
+ return -EINVAL;
+ }
+
+ case DMA_MEM_TYPE_KMALLOC:
+ {
+#if ALLOW_MAP_OF_KMALLOC_MEMORY
+ dma_unmap_single(NULL,
+ segment->physAddr,
+ segment->numBytes,
+ memMap->dir);
+#endif
+ break;
+ }
+
+ case DMA_MEM_TYPE_DMA:
+ {
+ dma_sync_single_for_cpu(NULL,
+ segment->
+ physAddr,
+ segment->
+ numBytes,
+ memMap->dir);
+ break;
+ }
+
+ case DMA_MEM_TYPE_USER:
+ {
+ /* Nothing to do here. */
+
+ break;
+ }
+
+ default:
+ {
+ printk(KERN_ERR
+ "%s: Unsupported memory type: %d\n",
+ __func__, region->memType);
+ return -EINVAL;
+ }
+ }
+
+ segment->virtAddr = NULL;
+ segment->physAddr = 0;
+ segment->numBytes = 0;
+ }
+
+ if (region->numLockedPages > 0) {
+ int pageIdx;
+
+ /* Some user pages were locked. We need to go and unlock them now. */
+
+ for (pageIdx = 0; pageIdx < region->numLockedPages;
+ pageIdx++) {
+ struct page *page =
+ region->lockedPages[pageIdx];
+
+ if (memMap->dir == DMA_FROM_DEVICE) {
+ SetPageDirty(page);
+ }
+ page_cache_release(page);
+ }
+ kfree(region->lockedPages);
+ region->numLockedPages = 0;
+ region->lockedPages = NULL;
+ }
+
+ region->memType = DMA_MEM_TYPE_NONE;
+ region->virtAddr = NULL;
+ region->numBytes = 0;
+ region->numSegmentsUsed = 0;
+ }
+ memMap->userTask = NULL;
+ memMap->numRegionsUsed = 0;
+ memMap->inUse = 0;
+
+ up(&memMap->lock);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(dma_unmap);