+ char dma_chan_link_map[OMAP_DMA4_LOGICAL_DMA_CH_COUNT];
+
+ dma_chan_link_map[lch] = 1;
+ /* Set the link register of the first channel */
+ enable_lnk(lch);
+
+ memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map));
+ cur_lch = dma_chan[lch].next_lch;
+ do {
+ next_lch = dma_chan[cur_lch].next_lch;
+
+ /* The loop case: we've been here already */
+ if (dma_chan_link_map[cur_lch])
+ break;
+ /* Mark the current channel */
+ dma_chan_link_map[cur_lch] = 1;
+
+ enable_lnk(cur_lch);
+ omap_enable_channel_irq(cur_lch);
+
+ cur_lch = next_lch;
+ } while (next_lch != -1);
+ } else if (cpu_is_omap242x() ||
+ (cpu_is_omap243x() && omap_type() <= OMAP2430_REV_ES1_0)) {
+
+ /* Errata: Need to write lch even if not using chaining */
+ dma_write(lch, CLNK_CTRL(lch));
+ }
+
+ omap_enable_channel_irq(lch);
+
+ l = dma_read(CCR(lch));
+
+ /*
+ * Errata: On ES2.0 BUFFERING disable must be set.
+ * This will always fail on ES1.0
+ */
+ if (cpu_is_omap24xx())
+ l |= OMAP_DMA_CCR_EN;
+
+ l |= OMAP_DMA_CCR_EN;
+ dma_write(l, CCR(lch));
+
+ dma_chan[lch].flags |= OMAP_DMA_ACTIVE;
+}
+EXPORT_SYMBOL(omap_start_dma);
+
+void omap_stop_dma(int lch)
+{
+ u32 l;
+
+ /* Disable all interrupts on the channel */
+ if (cpu_class_is_omap1())
+ dma_write(0, CICR(lch));
+
+ l = dma_read(CCR(lch));
+ l &= ~OMAP_DMA_CCR_EN;
+ dma_write(l, CCR(lch));
+
+ if (!omap_dma_in_1510_mode() && dma_chan[lch].next_lch != -1) {
+ int next_lch, cur_lch = lch;
+ char dma_chan_link_map[OMAP_DMA4_LOGICAL_DMA_CH_COUNT];
+
+ memset(dma_chan_link_map, 0, sizeof(dma_chan_link_map));
+ do {
+ /* The loop case: we've been here already */
+ if (dma_chan_link_map[cur_lch])
+ break;
+ /* Mark the current channel */
+ dma_chan_link_map[cur_lch] = 1;
+
+ disable_lnk(cur_lch);
+
+ next_lch = dma_chan[cur_lch].next_lch;
+ cur_lch = next_lch;
+ } while (next_lch != -1);
+ }
+
+ dma_chan[lch].flags &= ~OMAP_DMA_ACTIVE;
+}
+EXPORT_SYMBOL(omap_stop_dma);
+
+/*
+ * Allows changing the DMA callback function or data. This may be needed if
+ * the driver shares a single DMA channel for multiple dma triggers.
+ */
+int omap_set_dma_callback(int lch,
+ void (*callback)(int lch, u16 ch_status, void *data),
+ void *data)
+{
+ unsigned long flags;
+
+ if (lch < 0)
+ return -ENODEV;
+
+ spin_lock_irqsave(&dma_chan_lock, flags);
+ if (dma_chan[lch].dev_id == -1) {
+ printk(KERN_ERR "DMA callback for not set for free channel\n");
+ spin_unlock_irqrestore(&dma_chan_lock, flags);
+ return -EINVAL;
+ }
+ dma_chan[lch].callback = callback;
+ dma_chan[lch].data = data;
+ spin_unlock_irqrestore(&dma_chan_lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(omap_set_dma_callback);
+
+/*
+ * Returns current physical source address for the given DMA channel.
+ * If the channel is running the caller must disable interrupts prior calling
+ * this function and process the returned value before re-enabling interrupt to
+ * prevent races with the interrupt handler. Note that in continuous mode there
+ * is a chance for CSSA_L register overflow inbetween the two reads resulting
+ * in incorrect return value.
+ */
+dma_addr_t omap_get_dma_src_pos(int lch)
+{
+ dma_addr_t offset = 0;
+
+ if (cpu_is_omap15xx())
+ offset = dma_read(CPC(lch));
+ else
+ offset = dma_read(CSAC(lch));
+
+ /*
+ * omap 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
+ * read before the DMA controller finished disabling the channel.
+ */
+ if (!cpu_is_omap15xx() && offset == 0)
+ offset = dma_read(CSAC(lch));
+
+ if (cpu_class_is_omap1())
+ offset |= (dma_read(CSSA_U(lch)) << 16);
+
+ return offset;
+}
+EXPORT_SYMBOL(omap_get_dma_src_pos);
+
+/*
+ * Returns current physical destination address for the given DMA channel.
+ * If the channel is running the caller must disable interrupts prior calling
+ * this function and process the returned value before re-enabling interrupt to
+ * prevent races with the interrupt handler. Note that in continuous mode there
+ * is a chance for CDSA_L register overflow inbetween the two reads resulting
+ * in incorrect return value.
+ */
+dma_addr_t omap_get_dma_dst_pos(int lch)
+{
+ dma_addr_t offset = 0;
+
+ if (cpu_is_omap15xx())
+ offset = dma_read(CPC(lch));
+ else
+ offset = dma_read(CDAC(lch));
+
+ /*
+ * omap 3.2/3.3 erratum: sometimes 0 is returned if CSAC/CDAC is
+ * read before the DMA controller finished disabling the channel.
+ */
+ if (!cpu_is_omap15xx() && offset == 0)
+ offset = dma_read(CDAC(lch));
+
+ if (cpu_class_is_omap1())
+ offset |= (dma_read(CDSA_U(lch)) << 16);
+
+ return offset;
+}
+EXPORT_SYMBOL(omap_get_dma_dst_pos);
+
+int omap_get_dma_active_status(int lch)
+{
+ return (dma_read(CCR(lch)) & OMAP_DMA_CCR_EN) != 0;
+}
+EXPORT_SYMBOL(omap_get_dma_active_status);
+
+int omap_dma_running(void)
+{
+ int lch;
+
+ /* Check if LCD DMA is running */
+ if (cpu_is_omap16xx())
+ if (omap_readw(OMAP1610_DMA_LCD_CCR) & OMAP_DMA_CCR_EN)
+ return 1;
+
+ for (lch = 0; lch < dma_chan_count; lch++)
+ if (dma_read(CCR(lch)) & OMAP_DMA_CCR_EN)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * lch_queue DMA will start right after lch_head one is finished.
+ * For this DMA link to start, you still need to start (see omap_start_dma)
+ * the first one. That will fire up the entire queue.
+ */
+void omap_dma_link_lch(int lch_head, int lch_queue)
+{
+ if (omap_dma_in_1510_mode()) {
+ if (lch_head == lch_queue) {
+ dma_write(dma_read(CCR(lch_head)) | (3 << 8),
+ CCR(lch_head));
+ return;
+ }
+ printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
+ BUG();
+ return;
+ }
+
+ if ((dma_chan[lch_head].dev_id == -1) ||
+ (dma_chan[lch_queue].dev_id == -1)) {
+ printk(KERN_ERR "omap_dma: trying to link "
+ "non requested channels\n");
+ dump_stack();
+ }
+
+ dma_chan[lch_head].next_lch = lch_queue;
+}
+EXPORT_SYMBOL(omap_dma_link_lch);
+
+/*
+ * Once the DMA queue is stopped, we can destroy it.
+ */
+void omap_dma_unlink_lch(int lch_head, int lch_queue)
+{
+ if (omap_dma_in_1510_mode()) {
+ if (lch_head == lch_queue) {
+ dma_write(dma_read(CCR(lch_head)) & ~(3 << 8),
+ CCR(lch_head));
+ return;
+ }
+ printk(KERN_ERR "DMA linking is not supported in 1510 mode\n");
+ BUG();
+ return;
+ }
+
+ if (dma_chan[lch_head].next_lch != lch_queue ||
+ dma_chan[lch_head].next_lch == -1) {
+ printk(KERN_ERR "omap_dma: trying to unlink "
+ "non linked channels\n");
+ dump_stack();
+ }
+
+ if ((dma_chan[lch_head].flags & OMAP_DMA_ACTIVE) ||
+ (dma_chan[lch_head].flags & OMAP_DMA_ACTIVE)) {
+ printk(KERN_ERR "omap_dma: You need to stop the DMA channels "
+ "before unlinking\n");
+ dump_stack();
+ }
+
+ dma_chan[lch_head].next_lch = -1;
+}
+EXPORT_SYMBOL(omap_dma_unlink_lch);
+
+/*----------------------------------------------------------------------------*/
+
+#ifndef CONFIG_ARCH_OMAP1
+/* Create chain of DMA channesls */
+static void create_dma_lch_chain(int lch_head, int lch_queue)
+{
+ u32 l;
+
+ /* Check if this is the first link in chain */
+ if (dma_chan[lch_head].next_linked_ch == -1) {
+ dma_chan[lch_head].next_linked_ch = lch_queue;
+ dma_chan[lch_head].prev_linked_ch = lch_queue;
+ dma_chan[lch_queue].next_linked_ch = lch_head;
+ dma_chan[lch_queue].prev_linked_ch = lch_head;
+ }
+
+ /* a link exists, link the new channel in circular chain */
+ else {
+ dma_chan[lch_queue].next_linked_ch =
+ dma_chan[lch_head].next_linked_ch;
+ dma_chan[lch_queue].prev_linked_ch = lch_head;
+ dma_chan[lch_head].next_linked_ch = lch_queue;
+ dma_chan[dma_chan[lch_queue].next_linked_ch].prev_linked_ch =
+ lch_queue;
+ }
+
+ l = dma_read(CLNK_CTRL(lch_head));
+ l &= ~(0x1f);
+ l |= lch_queue;
+ dma_write(l, CLNK_CTRL(lch_head));
+
+ l = dma_read(CLNK_CTRL(lch_queue));
+ l &= ~(0x1f);
+ l |= (dma_chan[lch_queue].next_linked_ch);
+ dma_write(l, CLNK_CTRL(lch_queue));
+}
+
+/**
+ * @brief omap_request_dma_chain : Request a chain of DMA channels
+ *
+ * @param dev_id - Device id using the dma channel
+ * @param dev_name - Device name
+ * @param callback - Call back function
+ * @chain_id -
+ * @no_of_chans - Number of channels requested
+ * @chain_mode - Dynamic or static chaining : OMAP_DMA_STATIC_CHAIN
+ * OMAP_DMA_DYNAMIC_CHAIN
+ * @params - Channel parameters
+ *
+ * @return - Success : 0
+ * Failure: -EINVAL/-ENOMEM
+ */
+int omap_request_dma_chain(int dev_id, const char *dev_name,
+ void (*callback) (int lch, u16 ch_status,
+ void *data),
+ int *chain_id, int no_of_chans, int chain_mode,
+ struct omap_dma_channel_params params)
+{
+ int *channels;
+ int i, err;
+
+ /* Is the chain mode valid ? */
+ if (chain_mode != OMAP_DMA_STATIC_CHAIN
+ && chain_mode != OMAP_DMA_DYNAMIC_CHAIN) {
+ printk(KERN_ERR "Invalid chain mode requested\n");
+ return -EINVAL;
+ }
+
+ if (unlikely((no_of_chans < 1
+ || no_of_chans > dma_lch_count))) {
+ printk(KERN_ERR "Invalid Number of channels requested\n");
+ return -EINVAL;
+ }
+
+ /* Allocate a queue to maintain the status of the channels
+ * in the chain */
+ channels = kmalloc(sizeof(*channels) * no_of_chans, GFP_KERNEL);
+ if (channels == NULL) {
+ printk(KERN_ERR "omap_dma: No memory for channel queue\n");
+ return -ENOMEM;
+ }
+
+ /* request and reserve DMA channels for the chain */
+ for (i = 0; i < no_of_chans; i++) {
+ err = omap_request_dma(dev_id, dev_name,
+ callback, NULL, &channels[i]);
+ if (err < 0) {
+ int j;
+ for (j = 0; j < i; j++)
+ omap_free_dma(channels[j]);
+ kfree(channels);
+ printk(KERN_ERR "omap_dma: Request failed %d\n", err);
+ return err;
+ }
+ dma_chan[channels[i]].prev_linked_ch = -1;
+ dma_chan[channels[i]].state = DMA_CH_NOTSTARTED;
+
+ /*
+ * Allowing client drivers to set common parameters now,
+ * so that later only relevant (src_start, dest_start
+ * and element count) can be set
+ */
+ omap_set_dma_params(channels[i], ¶ms);
+ }
+
+ *chain_id = channels[0];
+ dma_linked_lch[*chain_id].linked_dmach_q = channels;
+ dma_linked_lch[*chain_id].chain_mode = chain_mode;
+ dma_linked_lch[*chain_id].chain_state = DMA_CHAIN_NOTSTARTED;
+ dma_linked_lch[*chain_id].no_of_lchs_linked = no_of_chans;
+
+ for (i = 0; i < no_of_chans; i++)
+ dma_chan[channels[i]].chain_id = *chain_id;
+
+ /* Reset the Queue pointers */
+ OMAP_DMA_CHAIN_QINIT(*chain_id);
+
+ /* Set up the chain */
+ if (no_of_chans == 1)
+ create_dma_lch_chain(channels[0], channels[0]);
+ else {
+ for (i = 0; i < (no_of_chans - 1); i++)
+ create_dma_lch_chain(channels[i], channels[i + 1]);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(omap_request_dma_chain);
+
+/**
+ * @brief omap_modify_dma_chain_param : Modify the chain's params - Modify the
+ * params after setting it. Dont do this while dma is running!!
+ *
+ * @param chain_id - Chained logical channel id.
+ * @param params
+ *
+ * @return - Success : 0
+ * Failure : -EINVAL
+ */
+int omap_modify_dma_chain_params(int chain_id,
+ struct omap_dma_channel_params params)
+{
+ int *channels;
+ u32 i;
+
+ /* Check for input params */
+ if (unlikely((chain_id < 0
+ || chain_id >= dma_lch_count))) {
+ printk(KERN_ERR "Invalid chain id\n");
+ return -EINVAL;
+ }
+
+ /* Check if the chain exists */
+ if (dma_linked_lch[chain_id].linked_dmach_q == NULL) {
+ printk(KERN_ERR "Chain doesn't exists\n");
+ return -EINVAL;
+ }
+ channels = dma_linked_lch[chain_id].linked_dmach_q;
+
+ for (i = 0; i < dma_linked_lch[chain_id].no_of_lchs_linked; i++) {
+ /*
+ * Allowing client drivers to set common parameters now,
+ * so that later only relevant (src_start, dest_start
+ * and element count) can be set
+ */
+ omap_set_dma_params(channels[i], ¶ms);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(omap_modify_dma_chain_params);
+
+/**
+ * @brief omap_free_dma_chain - Free all the logical channels in a chain.
+ *
+ * @param chain_id
+ *
+ * @return - Success : 0
+ * Failure : -EINVAL
+ */
+int omap_free_dma_chain(int chain_id)
+{
+ int *channels;
+ u32 i;
+
+ /* Check for input params */
+ if (unlikely((chain_id < 0 || chain_id >= dma_lch_count))) {
+ printk(KERN_ERR "Invalid chain id\n");
+ return -EINVAL;
+ }
+
+ /* Check if the chain exists */
+ if (dma_linked_lch[chain_id].linked_dmach_q == NULL) {
+ printk(KERN_ERR "Chain doesn't exists\n");
+ return -EINVAL;
+ }
+
+ channels = dma_linked_lch[chain_id].linked_dmach_q;
+ for (i = 0; i < dma_linked_lch[chain_id].no_of_lchs_linked; i++) {
+ dma_chan[channels[i]].next_linked_ch = -1;
+ dma_chan[channels[i]].prev_linked_ch = -1;
+ dma_chan[channels[i]].chain_id = -1;
+ dma_chan[channels[i]].state = DMA_CH_NOTSTARTED;
+ omap_free_dma(channels[i]);
+ }
+
+ kfree(channels);
+
+ dma_linked_lch[chain_id].linked_dmach_q = NULL;
+ dma_linked_lch[chain_id].chain_mode = -1;
+ dma_linked_lch[chain_id].chain_state = -1;
+
+ return (0);
+}
+EXPORT_SYMBOL(omap_free_dma_chain);
+
+/**
+ * @brief omap_dma_chain_status - Check if the chain is in
+ * active / inactive state.
+ * @param chain_id
+ *
+ * @return - Success : OMAP_DMA_CHAIN_ACTIVE/OMAP_DMA_CHAIN_INACTIVE
+ * Failure : -EINVAL
+ */
+int omap_dma_chain_status(int chain_id)
+{
+ /* Check for input params */
+ if (unlikely((chain_id < 0 || chain_id >= dma_lch_count))) {
+ printk(KERN_ERR "Invalid chain id\n");
+ return -EINVAL;
+ }
+
+ /* Check if the chain exists */
+ if (dma_linked_lch[chain_id].linked_dmach_q == NULL) {
+ printk(KERN_ERR "Chain doesn't exists\n");
+ return -EINVAL;
+ }
+ pr_debug("CHAINID=%d, qcnt=%d\n", chain_id,
+ dma_linked_lch[chain_id].q_count);
+
+ if (OMAP_DMA_CHAIN_QEMPTY(chain_id))
+ return OMAP_DMA_CHAIN_INACTIVE;
+
+ return OMAP_DMA_CHAIN_ACTIVE;
+}
+EXPORT_SYMBOL(omap_dma_chain_status);
+
+/**
+ * @brief omap_dma_chain_a_transfer - Get a free channel from a chain,
+ * set the params and start the transfer.
+ *
+ * @param chain_id
+ * @param src_start - buffer start address
+ * @param dest_start - Dest address
+ * @param elem_count
+ * @param frame_count
+ * @param callbk_data - channel callback parameter data.
+ *
+ * @return - Success : 0
+ * Failure: -EINVAL/-EBUSY
+ */
+int omap_dma_chain_a_transfer(int chain_id, int src_start, int dest_start,
+ int elem_count, int frame_count, void *callbk_data)
+{
+ int *channels;
+ u32 l, lch;
+ int start_dma = 0;
+
+ /*
+ * if buffer size is less than 1 then there is
+ * no use of starting the chain
+ */
+ if (elem_count < 1) {
+ printk(KERN_ERR "Invalid buffer size\n");
+ return -EINVAL;
+ }
+
+ /* Check for input params */
+ if (unlikely((chain_id < 0
+ || chain_id >= dma_lch_count))) {
+ printk(KERN_ERR "Invalid chain id\n");
+ return -EINVAL;
+ }
+
+ /* Check if the chain exists */
+ if (dma_linked_lch[chain_id].linked_dmach_q == NULL) {
+ printk(KERN_ERR "Chain doesn't exist\n");
+ return -EINVAL;
+ }
+
+ /* Check if all the channels in chain are in use */
+ if (OMAP_DMA_CHAIN_QFULL(chain_id))
+ return -EBUSY;