V4L/DVB (9815): omap2: add OMAP2 camera driver.

Add a driver for the OMAP2 camera block. OMAP2 is used in e.g. Nokia
N800/N810 internet tablet.

This driver uses the V4L2 internal ioctl interface.

Signed-off-by: Sakari Ailus <sakari.ailus@nokia.com>
Signed-off-by: Trilok Soni <soni.trilok@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

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 00000000000..1d54b86c936
--- /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);
+}