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path: root/drivers/media/video/omap24xxcam-dma.c
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Diffstat (limited to 'drivers/media/video/omap24xxcam-dma.c')
-rw-r--r--drivers/media/video/omap24xxcam-dma.c601
1 files changed, 601 insertions, 0 deletions
diff --git a/drivers/media/video/omap24xxcam-dma.c b/drivers/media/video/omap24xxcam-dma.c
new file mode 100644
index 000000000000..1d54b86c936b
--- /dev/null
+++ b/drivers/media/video/omap24xxcam-dma.c
@@ -0,0 +1,601 @@
+/*
+ * drivers/media/video/omap24xxcam-dma.c
+ *
+ * Copyright (C) 2004 MontaVista Software, Inc.
+ * Copyright (C) 2004 Texas Instruments.
+ * Copyright (C) 2007 Nokia Corporation.
+ *
+ * Contact: Sakari Ailus <sakari.ailus@nokia.com>
+ *
+ * Based on code from Andy Lowe <source@mvista.com> and
+ * David Cohen <david.cohen@indt.org.br>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/scatterlist.h>
+
+#include "omap24xxcam.h"
+
+/*
+ *
+ * DMA hardware.
+ *
+ */
+
+/* Ack all interrupt on CSR and IRQSTATUS_L0 */
+static void omap24xxcam_dmahw_ack_all(unsigned long base)
+{
+ u32 csr;
+ int i;
+
+ for (i = 0; i < NUM_CAMDMA_CHANNELS; ++i) {
+ csr = omap24xxcam_reg_in(base, CAMDMA_CSR(i));
+ /* ack interrupt in CSR */
+ omap24xxcam_reg_out(base, CAMDMA_CSR(i), csr);
+ }
+ omap24xxcam_reg_out(base, CAMDMA_IRQSTATUS_L0, 0xf);
+}
+
+/* Ack dmach on CSR and IRQSTATUS_L0 */
+static u32 omap24xxcam_dmahw_ack_ch(unsigned long base, int dmach)
+{
+ u32 csr;
+
+ csr = omap24xxcam_reg_in(base, CAMDMA_CSR(dmach));
+ /* ack interrupt in CSR */
+ omap24xxcam_reg_out(base, CAMDMA_CSR(dmach), csr);
+ /* ack interrupt in IRQSTATUS */
+ omap24xxcam_reg_out(base, CAMDMA_IRQSTATUS_L0, (1 << dmach));
+
+ return csr;
+}
+
+static int omap24xxcam_dmahw_running(unsigned long base, int dmach)
+{
+ return omap24xxcam_reg_in(base, CAMDMA_CCR(dmach)) & CAMDMA_CCR_ENABLE;
+}
+
+static void omap24xxcam_dmahw_transfer_setup(unsigned long base, int dmach,
+ dma_addr_t start, u32 len)
+{
+ omap24xxcam_reg_out(base, CAMDMA_CCR(dmach),
+ CAMDMA_CCR_SEL_SRC_DST_SYNC
+ | CAMDMA_CCR_BS
+ | CAMDMA_CCR_DST_AMODE_POST_INC
+ | CAMDMA_CCR_SRC_AMODE_POST_INC
+ | CAMDMA_CCR_FS
+ | CAMDMA_CCR_WR_ACTIVE
+ | CAMDMA_CCR_RD_ACTIVE
+ | CAMDMA_CCR_SYNCHRO_CAMERA);
+ omap24xxcam_reg_out(base, CAMDMA_CLNK_CTRL(dmach), 0);
+ omap24xxcam_reg_out(base, CAMDMA_CEN(dmach), len);
+ omap24xxcam_reg_out(base, CAMDMA_CFN(dmach), 1);
+ omap24xxcam_reg_out(base, CAMDMA_CSDP(dmach),
+ CAMDMA_CSDP_WRITE_MODE_POSTED
+ | CAMDMA_CSDP_DST_BURST_EN_32
+ | CAMDMA_CSDP_DST_PACKED
+ | CAMDMA_CSDP_SRC_BURST_EN_32
+ | CAMDMA_CSDP_SRC_PACKED
+ | CAMDMA_CSDP_DATA_TYPE_8BITS);
+ omap24xxcam_reg_out(base, CAMDMA_CSSA(dmach), 0);
+ omap24xxcam_reg_out(base, CAMDMA_CDSA(dmach), start);
+ omap24xxcam_reg_out(base, CAMDMA_CSEI(dmach), 0);
+ omap24xxcam_reg_out(base, CAMDMA_CSFI(dmach), DMA_THRESHOLD);
+ omap24xxcam_reg_out(base, CAMDMA_CDEI(dmach), 0);
+ omap24xxcam_reg_out(base, CAMDMA_CDFI(dmach), 0);
+ omap24xxcam_reg_out(base, CAMDMA_CSR(dmach),
+ CAMDMA_CSR_MISALIGNED_ERR
+ | CAMDMA_CSR_SECURE_ERR
+ | CAMDMA_CSR_TRANS_ERR
+ | CAMDMA_CSR_BLOCK
+ | CAMDMA_CSR_DROP);
+ omap24xxcam_reg_out(base, CAMDMA_CICR(dmach),
+ CAMDMA_CICR_MISALIGNED_ERR_IE
+ | CAMDMA_CICR_SECURE_ERR_IE
+ | CAMDMA_CICR_TRANS_ERR_IE
+ | CAMDMA_CICR_BLOCK_IE
+ | CAMDMA_CICR_DROP_IE);
+}
+
+static void omap24xxcam_dmahw_transfer_start(unsigned long base, int dmach)
+{
+ omap24xxcam_reg_out(base, CAMDMA_CCR(dmach),
+ CAMDMA_CCR_SEL_SRC_DST_SYNC
+ | CAMDMA_CCR_BS
+ | CAMDMA_CCR_DST_AMODE_POST_INC
+ | CAMDMA_CCR_SRC_AMODE_POST_INC
+ | CAMDMA_CCR_ENABLE
+ | CAMDMA_CCR_FS
+ | CAMDMA_CCR_SYNCHRO_CAMERA);
+}
+
+static void omap24xxcam_dmahw_transfer_chain(unsigned long base, int dmach,
+ int free_dmach)
+{
+ int prev_dmach, ch;
+
+ if (dmach == 0)
+ prev_dmach = NUM_CAMDMA_CHANNELS - 1;
+ else
+ prev_dmach = dmach - 1;
+ omap24xxcam_reg_out(base, CAMDMA_CLNK_CTRL(prev_dmach),
+ CAMDMA_CLNK_CTRL_ENABLE_LNK | dmach);
+ /* Did we chain the DMA transfer before the previous one
+ * finished?
+ */
+ ch = (dmach + free_dmach) % NUM_CAMDMA_CHANNELS;
+ while (!(omap24xxcam_reg_in(base, CAMDMA_CCR(ch))
+ & CAMDMA_CCR_ENABLE)) {
+ if (ch == dmach) {
+ /* The previous transfer has ended and this one
+ * hasn't started, so we must not have chained
+ * to the previous one in time. We'll have to
+ * start it now.
+ */
+ omap24xxcam_dmahw_transfer_start(base, dmach);
+ break;
+ } else
+ ch = (ch + 1) % NUM_CAMDMA_CHANNELS;
+ }
+}
+
+/* Abort all chained DMA transfers. After all transfers have been
+ * aborted and the DMA controller is idle, the completion routines for
+ * any aborted transfers will be called in sequence. The DMA
+ * controller may not be idle after this routine completes, because
+ * the completion routines might start new transfers.
+ */
+static void omap24xxcam_dmahw_abort_ch(unsigned long base, int dmach)
+{
+ /* mask all interrupts from this channel */
+ omap24xxcam_reg_out(base, CAMDMA_CICR(dmach), 0);
+ /* unlink this channel */
+ omap24xxcam_reg_merge(base, CAMDMA_CLNK_CTRL(dmach), 0,
+ CAMDMA_CLNK_CTRL_ENABLE_LNK);
+ /* disable this channel */
+ omap24xxcam_reg_merge(base, CAMDMA_CCR(dmach), 0, CAMDMA_CCR_ENABLE);
+}
+
+static void omap24xxcam_dmahw_init(unsigned long base)
+{
+ omap24xxcam_reg_out(base, CAMDMA_OCP_SYSCONFIG,
+ CAMDMA_OCP_SYSCONFIG_MIDLEMODE_FSTANDBY
+ | CAMDMA_OCP_SYSCONFIG_SIDLEMODE_FIDLE
+ | CAMDMA_OCP_SYSCONFIG_AUTOIDLE);
+
+ omap24xxcam_reg_merge(base, CAMDMA_GCR, 0x10,
+ CAMDMA_GCR_MAX_CHANNEL_FIFO_DEPTH);
+
+ omap24xxcam_reg_out(base, CAMDMA_IRQENABLE_L0, 0xf);
+}
+
+/*
+ *
+ * Individual DMA channel handling.
+ *
+ */
+
+/* Start a DMA transfer from the camera to memory.
+ * Returns zero if the transfer was successfully started, or non-zero if all
+ * DMA channels are already in use or starting is currently inhibited.
+ */
+static int omap24xxcam_dma_start(struct omap24xxcam_dma *dma, dma_addr_t start,
+ u32 len, dma_callback_t callback, void *arg)
+{
+ unsigned long flags;
+ int dmach;
+
+ spin_lock_irqsave(&dma->lock, flags);
+
+ if (!dma->free_dmach || atomic_read(&dma->dma_stop)) {
+ spin_unlock_irqrestore(&dma->lock, flags);
+ return -EBUSY;
+ }
+
+ dmach = dma->next_dmach;
+
+ dma->ch_state[dmach].callback = callback;
+ dma->ch_state[dmach].arg = arg;
+
+ omap24xxcam_dmahw_transfer_setup(dma->base, dmach, start, len);
+
+ /* We're ready to start the DMA transfer. */
+
+ if (dma->free_dmach < NUM_CAMDMA_CHANNELS) {
+ /* A transfer is already in progress, so try to chain to it. */
+ omap24xxcam_dmahw_transfer_chain(dma->base, dmach,
+ dma->free_dmach);
+ } else {
+ /* No transfer is in progress, so we'll just start this one
+ * now.
+ */
+ omap24xxcam_dmahw_transfer_start(dma->base, dmach);
+ }
+
+ dma->next_dmach = (dma->next_dmach + 1) % NUM_CAMDMA_CHANNELS;
+ dma->free_dmach--;
+
+ spin_unlock_irqrestore(&dma->lock, flags);
+
+ return 0;
+}
+
+/* Abort all chained DMA transfers. After all transfers have been
+ * aborted and the DMA controller is idle, the completion routines for
+ * any aborted transfers will be called in sequence. The DMA
+ * controller may not be idle after this routine completes, because
+ * the completion routines might start new transfers.
+ */
+static void omap24xxcam_dma_abort(struct omap24xxcam_dma *dma, u32 csr)
+{
+ unsigned long flags;
+ int dmach, i, free_dmach;
+ dma_callback_t callback;
+ void *arg;
+
+ spin_lock_irqsave(&dma->lock, flags);
+
+ /* stop any DMA transfers in progress */
+ dmach = (dma->next_dmach + dma->free_dmach) % NUM_CAMDMA_CHANNELS;
+ for (i = 0; i < NUM_CAMDMA_CHANNELS; i++) {
+ omap24xxcam_dmahw_abort_ch(dma->base, dmach);
+ dmach = (dmach + 1) % NUM_CAMDMA_CHANNELS;
+ }
+
+ /* We have to be careful here because the callback routine
+ * might start a new DMA transfer, and we only want to abort
+ * transfers that were started before this routine was called.
+ */
+ free_dmach = dma->free_dmach;
+ while ((dma->free_dmach < NUM_CAMDMA_CHANNELS) &&
+ (free_dmach < NUM_CAMDMA_CHANNELS)) {
+ dmach = (dma->next_dmach + dma->free_dmach)
+ % NUM_CAMDMA_CHANNELS;
+ callback = dma->ch_state[dmach].callback;
+ arg = dma->ch_state[dmach].arg;
+ dma->free_dmach++;
+ free_dmach++;
+ if (callback) {
+ /* leave interrupts disabled during callback */
+ spin_unlock(&dma->lock);
+ (*callback) (dma, csr, arg);
+ spin_lock(&dma->lock);
+ }
+ }
+
+ spin_unlock_irqrestore(&dma->lock, flags);
+}
+
+/* Abort all chained DMA transfers. After all transfers have been
+ * aborted and the DMA controller is idle, the completion routines for
+ * any aborted transfers will be called in sequence. If the completion
+ * routines attempt to start a new DMA transfer it will fail, so the
+ * DMA controller will be idle after this routine completes.
+ */
+static void omap24xxcam_dma_stop(struct omap24xxcam_dma *dma, u32 csr)
+{
+ atomic_inc(&dma->dma_stop);
+ omap24xxcam_dma_abort(dma, csr);
+ atomic_dec(&dma->dma_stop);
+}
+
+/* Camera DMA interrupt service routine. */
+void omap24xxcam_dma_isr(struct omap24xxcam_dma *dma)
+{
+ int dmach;
+ dma_callback_t callback;
+ void *arg;
+ u32 csr;
+ const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+ | CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+ | CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+
+ spin_lock(&dma->lock);
+
+ if (dma->free_dmach == NUM_CAMDMA_CHANNELS) {
+ /* A camera DMA interrupt occurred while all channels
+ * are idle, so we'll acknowledge the interrupt in the
+ * IRQSTATUS register and exit.
+ */
+ omap24xxcam_dmahw_ack_all(dma->base);
+ spin_unlock(&dma->lock);
+ return;
+ }
+
+ while (dma->free_dmach < NUM_CAMDMA_CHANNELS) {
+ dmach = (dma->next_dmach + dma->free_dmach)
+ % NUM_CAMDMA_CHANNELS;
+ if (omap24xxcam_dmahw_running(dma->base, dmach)) {
+ /* This buffer hasn't finished yet, so we're done. */
+ break;
+ }
+ csr = omap24xxcam_dmahw_ack_ch(dma->base, dmach);
+ if (csr & csr_error) {
+ /* A DMA error occurred, so stop all DMA
+ * transfers in progress.
+ */
+ spin_unlock(&dma->lock);
+ omap24xxcam_dma_stop(dma, csr);
+ return;
+ } else {
+ callback = dma->ch_state[dmach].callback;
+ arg = dma->ch_state[dmach].arg;
+ dma->free_dmach++;
+ if (callback) {
+ spin_unlock(&dma->lock);
+ (*callback) (dma, csr, arg);
+ spin_lock(&dma->lock);
+ }
+ }
+ }
+
+ spin_unlock(&dma->lock);
+
+ omap24xxcam_sgdma_process(
+ container_of(dma, struct omap24xxcam_sgdma, dma));
+}
+
+void omap24xxcam_dma_hwinit(struct omap24xxcam_dma *dma)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&dma->lock, flags);
+
+ omap24xxcam_dmahw_init(dma->base);
+
+ spin_unlock_irqrestore(&dma->lock, flags);
+}
+
+static void omap24xxcam_dma_init(struct omap24xxcam_dma *dma,
+ unsigned long base)
+{
+ int ch;
+
+ /* group all channels on DMA IRQ0 and unmask irq */
+ spin_lock_init(&dma->lock);
+ dma->base = base;
+ dma->free_dmach = NUM_CAMDMA_CHANNELS;
+ dma->next_dmach = 0;
+ for (ch = 0; ch < NUM_CAMDMA_CHANNELS; ch++) {
+ dma->ch_state[ch].callback = NULL;
+ dma->ch_state[ch].arg = NULL;
+ }
+}
+
+/*
+ *
+ * Scatter-gather DMA.
+ *
+ * High-level DMA construct for transferring whole picture frames to
+ * memory that is discontinuous.
+ *
+ */
+
+/* DMA completion routine for the scatter-gather DMA fragments. */
+static void omap24xxcam_sgdma_callback(struct omap24xxcam_dma *dma, u32 csr,
+ void *arg)
+{
+ struct omap24xxcam_sgdma *sgdma =
+ container_of(dma, struct omap24xxcam_sgdma, dma);
+ int sgslot = (int)arg;
+ struct sgdma_state *sg_state;
+ const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+ | CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+ | CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+
+ spin_lock(&sgdma->lock);
+
+ /* We got an interrupt, we can remove the timer */
+ del_timer(&sgdma->reset_timer);
+
+ sg_state = sgdma->sg_state + sgslot;
+ if (!sg_state->queued_sglist) {
+ spin_unlock(&sgdma->lock);
+ printk(KERN_ERR "%s: sgdma completed when none queued!\n",
+ __func__);
+ return;
+ }
+
+ sg_state->csr |= csr;
+ if (!--sg_state->queued_sglist) {
+ /* Queue for this sglist is empty, so check to see if we're
+ * done.
+ */
+ if ((sg_state->next_sglist == sg_state->sglen)
+ || (sg_state->csr & csr_error)) {
+ sgdma_callback_t callback = sg_state->callback;
+ void *arg = sg_state->arg;
+ u32 sg_csr = sg_state->csr;
+ /* All done with this sglist */
+ sgdma->free_sgdma++;
+ if (callback) {
+ spin_unlock(&sgdma->lock);
+ (*callback) (sgdma, sg_csr, arg);
+ return;
+ }
+ }
+ }
+
+ spin_unlock(&sgdma->lock);
+}
+
+/* Start queued scatter-gather DMA transfers. */
+void omap24xxcam_sgdma_process(struct omap24xxcam_sgdma *sgdma)
+{
+ unsigned long flags;
+ int queued_sgdma, sgslot;
+ struct sgdma_state *sg_state;
+ const u32 csr_error = CAMDMA_CSR_MISALIGNED_ERR
+ | CAMDMA_CSR_SUPERVISOR_ERR | CAMDMA_CSR_SECURE_ERR
+ | CAMDMA_CSR_TRANS_ERR | CAMDMA_CSR_DROP;
+
+ spin_lock_irqsave(&sgdma->lock, flags);
+
+ queued_sgdma = NUM_SG_DMA - sgdma->free_sgdma;
+ sgslot = (sgdma->next_sgdma + sgdma->free_sgdma) % NUM_SG_DMA;
+ while (queued_sgdma > 0) {
+ sg_state = sgdma->sg_state + sgslot;
+ while ((sg_state->next_sglist < sg_state->sglen) &&
+ !(sg_state->csr & csr_error)) {
+ const struct scatterlist *sglist;
+ unsigned int len;
+
+ sglist = sg_state->sglist + sg_state->next_sglist;
+ /* try to start the next DMA transfer */
+ if (sg_state->next_sglist + 1 == sg_state->sglen) {
+ /*
+ * On the last sg, we handle the case where
+ * cam->img.pix.sizeimage % PAGE_ALIGN != 0
+ */
+ len = sg_state->len - sg_state->bytes_read;
+ } else {
+ len = sg_dma_len(sglist);
+ }
+
+ if (omap24xxcam_dma_start(&sgdma->dma,
+ sg_dma_address(sglist),
+ len,
+ omap24xxcam_sgdma_callback,
+ (void *)sgslot)) {
+ /* DMA start failed */
+ spin_unlock_irqrestore(&sgdma->lock, flags);
+ return;
+ } else {
+ unsigned long expires;
+ /* DMA start was successful */
+ sg_state->next_sglist++;
+ sg_state->bytes_read += len;
+ sg_state->queued_sglist++;
+
+ /* We start the reset timer */
+ expires = jiffies + HZ;
+ mod_timer(&sgdma->reset_timer, expires);
+ }
+ }
+ queued_sgdma--;
+ sgslot = (sgslot + 1) % NUM_SG_DMA;
+ }
+
+ spin_unlock_irqrestore(&sgdma->lock, flags);
+}
+
+/*
+ * Queue a scatter-gather DMA transfer from the camera to memory.
+ * Returns zero if the transfer was successfully queued, or non-zero
+ * if all of the scatter-gather slots are already in use.
+ */
+int omap24xxcam_sgdma_queue(struct omap24xxcam_sgdma *sgdma,
+ const struct scatterlist *sglist, int sglen,
+ int len, sgdma_callback_t callback, void *arg)
+{
+ unsigned long flags;
+ struct sgdma_state *sg_state;
+
+ if ((sglen < 0) || ((sglen > 0) & !sglist))
+ return -EINVAL;
+
+ spin_lock_irqsave(&sgdma->lock, flags);
+
+ if (!sgdma->free_sgdma) {
+ spin_unlock_irqrestore(&sgdma->lock, flags);
+ return -EBUSY;
+ }
+
+ sg_state = sgdma->sg_state + sgdma->next_sgdma;
+
+ sg_state->sglist = sglist;
+ sg_state->sglen = sglen;
+ sg_state->next_sglist = 0;
+ sg_state->bytes_read = 0;
+ sg_state->len = len;
+ sg_state->queued_sglist = 0;
+ sg_state->csr = 0;
+ sg_state->callback = callback;
+ sg_state->arg = arg;
+
+ sgdma->next_sgdma = (sgdma->next_sgdma + 1) % NUM_SG_DMA;
+ sgdma->free_sgdma--;
+
+ spin_unlock_irqrestore(&sgdma->lock, flags);
+
+ omap24xxcam_sgdma_process(sgdma);
+
+ return 0;
+}
+
+/* Sync scatter-gather DMA by aborting any DMA transfers currently in progress.
+ * Any queued scatter-gather DMA transactions that have not yet been started
+ * will remain queued. The DMA controller will be idle after this routine
+ * completes. When the scatter-gather queue is restarted, the next
+ * scatter-gather DMA transfer will begin at the start of a new transaction.
+ */
+void omap24xxcam_sgdma_sync(struct omap24xxcam_sgdma *sgdma)
+{
+ unsigned long flags;
+ int sgslot;
+ struct sgdma_state *sg_state;
+ u32 csr = CAMDMA_CSR_TRANS_ERR;
+
+ /* stop any DMA transfers in progress */
+ omap24xxcam_dma_stop(&sgdma->dma, csr);
+
+ spin_lock_irqsave(&sgdma->lock, flags);
+
+ if (sgdma->free_sgdma < NUM_SG_DMA) {
+ sgslot = (sgdma->next_sgdma + sgdma->free_sgdma) % NUM_SG_DMA;
+ sg_state = sgdma->sg_state + sgslot;
+ if (sg_state->next_sglist != 0) {
+ /* This DMA transfer was in progress, so abort it. */
+ sgdma_callback_t callback = sg_state->callback;
+ void *arg = sg_state->arg;
+ sgdma->free_sgdma++;
+ if (callback) {
+ /* leave interrupts masked */
+ spin_unlock(&sgdma->lock);
+ (*callback) (sgdma, csr, arg);
+ spin_lock(&sgdma->lock);
+ }
+ }
+ }
+
+ spin_unlock_irqrestore(&sgdma->lock, flags);
+}
+
+void omap24xxcam_sgdma_init(struct omap24xxcam_sgdma *sgdma,
+ unsigned long base,
+ void (*reset_callback)(unsigned long data),
+ unsigned long reset_callback_data)
+{
+ int sg;
+
+ spin_lock_init(&sgdma->lock);
+ sgdma->free_sgdma = NUM_SG_DMA;
+ sgdma->next_sgdma = 0;
+ for (sg = 0; sg < NUM_SG_DMA; sg++) {
+ sgdma->sg_state[sg].sglen = 0;
+ sgdma->sg_state[sg].next_sglist = 0;
+ sgdma->sg_state[sg].bytes_read = 0;
+ sgdma->sg_state[sg].queued_sglist = 0;
+ sgdma->sg_state[sg].csr = 0;
+ sgdma->sg_state[sg].callback = NULL;
+ sgdma->sg_state[sg].arg = NULL;
+ }
+
+ omap24xxcam_dma_init(&sgdma->dma, base);
+ setup_timer(&sgdma->reset_timer, reset_callback, reset_callback_data);
+}