From 1d3564d91f94d0b598304eb6ebe3b83a83176f7a Mon Sep 17 00:00:00 2001 From: Guennadi Liakhovetski Date: Thu, 25 Aug 2011 13:26:53 -0300 Subject: [media] dmaengine: ipu-idmac: add support for the DMA_PAUSE control To support multi-size buffers in the mx3_camera V4L2 driver we have to be able to stop DMA on a channel without releasing descriptors and completely halting the hardware. Use the DMA_PAUSE control to implement this mode. Signed-off-by: Guennadi Liakhovetski Acked-by: Vinod Koul Signed-off-by: Mauro Carvalho Chehab --- drivers/dma/ipu/ipu_idmac.c | 65 +++++++++++++++++++++++++++++---------------- 1 file changed, 42 insertions(+), 23 deletions(-) (limited to 'drivers/dma/ipu') diff --git a/drivers/dma/ipu/ipu_idmac.c b/drivers/dma/ipu/ipu_idmac.c index 6815905a772..ddc2a133182 100644 --- a/drivers/dma/ipu/ipu_idmac.c +++ b/drivers/dma/ipu/ipu_idmac.c @@ -1307,6 +1307,7 @@ static irqreturn_t idmac_interrupt(int irq, void *dev_id) ipu_submit_buffer(ichan, descnew, sgnew, ichan->active_buffer) < 0) { callback = descnew->txd.callback; callback_param = descnew->txd.callback_param; + list_del_init(&descnew->list); spin_unlock(&ichan->lock); if (callback) callback(callback_param); @@ -1428,39 +1429,58 @@ static int __idmac_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd, { struct idmac_channel *ichan = to_idmac_chan(chan); struct idmac *idmac = to_idmac(chan->device); + struct ipu *ipu = to_ipu(idmac); + struct list_head *list, *tmp; unsigned long flags; int i; - /* Only supports DMA_TERMINATE_ALL */ - if (cmd != DMA_TERMINATE_ALL) - return -ENXIO; + switch (cmd) { + case DMA_PAUSE: + spin_lock_irqsave(&ipu->lock, flags); + ipu_ic_disable_task(ipu, chan->chan_id); - ipu_disable_channel(idmac, ichan, - ichan->status >= IPU_CHANNEL_ENABLED); + /* Return all descriptors into "prepared" state */ + list_for_each_safe(list, tmp, &ichan->queue) + list_del_init(list); - tasklet_disable(&to_ipu(idmac)->tasklet); + ichan->sg[0] = NULL; + ichan->sg[1] = NULL; - /* ichan->queue is modified in ISR, have to spinlock */ - spin_lock_irqsave(&ichan->lock, flags); - list_splice_init(&ichan->queue, &ichan->free_list); + spin_unlock_irqrestore(&ipu->lock, flags); - if (ichan->desc) - for (i = 0; i < ichan->n_tx_desc; i++) { - struct idmac_tx_desc *desc = ichan->desc + i; - if (list_empty(&desc->list)) - /* Descriptor was prepared, but not submitted */ - list_add(&desc->list, &ichan->free_list); + ichan->status = IPU_CHANNEL_INITIALIZED; + break; + case DMA_TERMINATE_ALL: + ipu_disable_channel(idmac, ichan, + ichan->status >= IPU_CHANNEL_ENABLED); - async_tx_clear_ack(&desc->txd); - } + tasklet_disable(&ipu->tasklet); - ichan->sg[0] = NULL; - ichan->sg[1] = NULL; - spin_unlock_irqrestore(&ichan->lock, flags); + /* ichan->queue is modified in ISR, have to spinlock */ + spin_lock_irqsave(&ichan->lock, flags); + list_splice_init(&ichan->queue, &ichan->free_list); - tasklet_enable(&to_ipu(idmac)->tasklet); + if (ichan->desc) + for (i = 0; i < ichan->n_tx_desc; i++) { + struct idmac_tx_desc *desc = ichan->desc + i; + if (list_empty(&desc->list)) + /* Descriptor was prepared, but not submitted */ + list_add(&desc->list, &ichan->free_list); - ichan->status = IPU_CHANNEL_INITIALIZED; + async_tx_clear_ack(&desc->txd); + } + + ichan->sg[0] = NULL; + ichan->sg[1] = NULL; + spin_unlock_irqrestore(&ichan->lock, flags); + + tasklet_enable(&ipu->tasklet); + + ichan->status = IPU_CHANNEL_INITIALIZED; + break; + default: + return -ENOSYS; + } return 0; } @@ -1663,7 +1683,6 @@ static void __exit ipu_idmac_exit(struct ipu *ipu) struct idmac_channel *ichan = ipu->channel + i; idmac_control(&ichan->dma_chan, DMA_TERMINATE_ALL, 0); - idmac_prep_slave_sg(&ichan->dma_chan, NULL, 0, DMA_NONE, 0); } dma_async_device_unregister(&idmac->dma); -- cgit v1.2.3