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path: root/drivers/media/pci/ivtv/ivtv-udma.c
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Diffstat (limited to 'drivers/media/pci/ivtv/ivtv-udma.c')
-rw-r--r--drivers/media/pci/ivtv/ivtv-udma.c234
1 files changed, 234 insertions, 0 deletions
diff --git a/drivers/media/pci/ivtv/ivtv-udma.c b/drivers/media/pci/ivtv/ivtv-udma.c
new file mode 100644
index 000000000000..7338cb2d0a38
--- /dev/null
+++ b/drivers/media/pci/ivtv/ivtv-udma.c
@@ -0,0 +1,234 @@
+/*
+ User DMA
+
+ Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com>
+ Copyright (C) 2004 Chris Kennedy <c@groovy.org>
+ Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl>
+
+ 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "ivtv-driver.h"
+#include "ivtv-udma.h"
+
+void ivtv_udma_get_page_info(struct ivtv_dma_page_info *dma_page, unsigned long first, unsigned long size)
+{
+ dma_page->uaddr = first & PAGE_MASK;
+ dma_page->offset = first & ~PAGE_MASK;
+ dma_page->tail = 1 + ((first+size-1) & ~PAGE_MASK);
+ dma_page->first = (first & PAGE_MASK) >> PAGE_SHIFT;
+ dma_page->last = ((first+size-1) & PAGE_MASK) >> PAGE_SHIFT;
+ dma_page->page_count = dma_page->last - dma_page->first + 1;
+ if (dma_page->page_count == 1) dma_page->tail -= dma_page->offset;
+}
+
+int ivtv_udma_fill_sg_list (struct ivtv_user_dma *dma, struct ivtv_dma_page_info *dma_page, int map_offset)
+{
+ int i, offset;
+ unsigned long flags;
+
+ if (map_offset < 0)
+ return map_offset;
+
+ offset = dma_page->offset;
+
+ /* Fill SG Array with new values */
+ for (i = 0; i < dma_page->page_count; i++) {
+ unsigned int len = (i == dma_page->page_count - 1) ?
+ dma_page->tail : PAGE_SIZE - offset;
+
+ if (PageHighMem(dma->map[map_offset])) {
+ void *src;
+
+ if (dma->bouncemap[map_offset] == NULL)
+ dma->bouncemap[map_offset] = alloc_page(GFP_KERNEL);
+ if (dma->bouncemap[map_offset] == NULL)
+ return -1;
+ local_irq_save(flags);
+ src = kmap_atomic(dma->map[map_offset]) + offset;
+ memcpy(page_address(dma->bouncemap[map_offset]) + offset, src, len);
+ kunmap_atomic(src);
+ local_irq_restore(flags);
+ sg_set_page(&dma->SGlist[map_offset], dma->bouncemap[map_offset], len, offset);
+ }
+ else {
+ sg_set_page(&dma->SGlist[map_offset], dma->map[map_offset], len, offset);
+ }
+ offset = 0;
+ map_offset++;
+ }
+ return map_offset;
+}
+
+void ivtv_udma_fill_sg_array (struct ivtv_user_dma *dma, u32 buffer_offset, u32 buffer_offset_2, u32 split) {
+ int i;
+ struct scatterlist *sg;
+
+ for (i = 0, sg = dma->SGlist; i < dma->SG_length; i++, sg++) {
+ dma->SGarray[i].size = cpu_to_le32(sg_dma_len(sg));
+ dma->SGarray[i].src = cpu_to_le32(sg_dma_address(sg));
+ dma->SGarray[i].dst = cpu_to_le32(buffer_offset);
+ buffer_offset += sg_dma_len(sg);
+
+ split -= sg_dma_len(sg);
+ if (split == 0)
+ buffer_offset = buffer_offset_2;
+ }
+}
+
+/* User DMA Buffers */
+void ivtv_udma_alloc(struct ivtv *itv)
+{
+ if (itv->udma.SG_handle == 0) {
+ /* Map DMA Page Array Buffer */
+ itv->udma.SG_handle = pci_map_single(itv->pdev, itv->udma.SGarray,
+ sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE);
+ ivtv_udma_sync_for_cpu(itv);
+ }
+}
+
+int ivtv_udma_setup(struct ivtv *itv, unsigned long ivtv_dest_addr,
+ void __user *userbuf, int size_in_bytes)
+{
+ struct ivtv_dma_page_info user_dma;
+ struct ivtv_user_dma *dma = &itv->udma;
+ int i, err;
+
+ IVTV_DEBUG_DMA("ivtv_udma_setup, dst: 0x%08x\n", (unsigned int)ivtv_dest_addr);
+
+ /* Still in USE */
+ if (dma->SG_length || dma->page_count) {
+ IVTV_DEBUG_WARN("ivtv_udma_setup: SG_length %d page_count %d still full?\n",
+ dma->SG_length, dma->page_count);
+ return -EBUSY;
+ }
+
+ ivtv_udma_get_page_info(&user_dma, (unsigned long)userbuf, size_in_bytes);
+
+ if (user_dma.page_count <= 0) {
+ IVTV_DEBUG_WARN("ivtv_udma_setup: Error %d page_count from %d bytes %d offset\n",
+ user_dma.page_count, size_in_bytes, user_dma.offset);
+ return -EINVAL;
+ }
+
+ /* Get user pages for DMA Xfer */
+ down_read(&current->mm->mmap_sem);
+ err = get_user_pages(current, current->mm,
+ user_dma.uaddr, user_dma.page_count, 0, 1, dma->map, NULL);
+ up_read(&current->mm->mmap_sem);
+
+ if (user_dma.page_count != err) {
+ IVTV_DEBUG_WARN("failed to map user pages, returned %d instead of %d\n",
+ err, user_dma.page_count);
+ if (err >= 0) {
+ for (i = 0; i < err; i++)
+ put_page(dma->map[i]);
+ return -EINVAL;
+ }
+ return err;
+ }
+
+ dma->page_count = user_dma.page_count;
+
+ /* Fill SG List with new values */
+ if (ivtv_udma_fill_sg_list(dma, &user_dma, 0) < 0) {
+ for (i = 0; i < dma->page_count; i++) {
+ put_page(dma->map[i]);
+ }
+ dma->page_count = 0;
+ return -ENOMEM;
+ }
+
+ /* Map SG List */
+ dma->SG_length = pci_map_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE);
+
+ /* Fill SG Array with new values */
+ ivtv_udma_fill_sg_array (dma, ivtv_dest_addr, 0, -1);
+
+ /* Tag SG Array with Interrupt Bit */
+ dma->SGarray[dma->SG_length - 1].size |= cpu_to_le32(0x80000000);
+
+ ivtv_udma_sync_for_device(itv);
+ return dma->page_count;
+}
+
+void ivtv_udma_unmap(struct ivtv *itv)
+{
+ struct ivtv_user_dma *dma = &itv->udma;
+ int i;
+
+ IVTV_DEBUG_INFO("ivtv_unmap_user_dma\n");
+
+ /* Nothing to free */
+ if (dma->page_count == 0)
+ return;
+
+ /* Unmap Scatterlist */
+ if (dma->SG_length) {
+ pci_unmap_sg(itv->pdev, dma->SGlist, dma->page_count, PCI_DMA_TODEVICE);
+ dma->SG_length = 0;
+ }
+ /* sync DMA */
+ ivtv_udma_sync_for_cpu(itv);
+
+ /* Release User Pages */
+ for (i = 0; i < dma->page_count; i++) {
+ put_page(dma->map[i]);
+ }
+ dma->page_count = 0;
+}
+
+void ivtv_udma_free(struct ivtv *itv)
+{
+ int i;
+
+ /* Unmap SG Array */
+ if (itv->udma.SG_handle) {
+ pci_unmap_single(itv->pdev, itv->udma.SG_handle,
+ sizeof(itv->udma.SGarray), PCI_DMA_TODEVICE);
+ }
+
+ /* Unmap Scatterlist */
+ if (itv->udma.SG_length) {
+ pci_unmap_sg(itv->pdev, itv->udma.SGlist, itv->udma.page_count, PCI_DMA_TODEVICE);
+ }
+
+ for (i = 0; i < IVTV_DMA_SG_OSD_ENT; i++) {
+ if (itv->udma.bouncemap[i])
+ __free_page(itv->udma.bouncemap[i]);
+ }
+}
+
+void ivtv_udma_start(struct ivtv *itv)
+{
+ IVTV_DEBUG_DMA("start UDMA\n");
+ write_reg(itv->udma.SG_handle, IVTV_REG_DECDMAADDR);
+ write_reg_sync(read_reg(IVTV_REG_DMAXFER) | 0x01, IVTV_REG_DMAXFER);
+ set_bit(IVTV_F_I_DMA, &itv->i_flags);
+ set_bit(IVTV_F_I_UDMA, &itv->i_flags);
+ clear_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags);
+}
+
+void ivtv_udma_prepare(struct ivtv *itv)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&itv->dma_reg_lock, flags);
+ if (!test_bit(IVTV_F_I_DMA, &itv->i_flags))
+ ivtv_udma_start(itv);
+ else
+ set_bit(IVTV_F_I_UDMA_PENDING, &itv->i_flags);
+ spin_unlock_irqrestore(&itv->dma_reg_lock, flags);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-28 01:58:44 +0100