[PATCH v4 12/58] dmaengine: hdmac: Split device_control

From: Maxime Ripard
Date: Tue Oct 28 2014 - 17:48:48 EST


Split the device_control callback of the Atmel HDMAC driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
drivers/dma/at_hdmac.c | 121 +++++++++++++++++++++++++++++--------------------
1 file changed, 73 insertions(+), 48 deletions(-)

diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index ca9dd2613283..86450b3442f2 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -972,11 +972,13 @@ err_out:
return NULL;
}

-static int set_runtime_config(struct dma_chan *chan,
- struct dma_slave_config *sconfig)
+static int atc_config(struct dma_chan *chan,
+ struct dma_slave_config *sconfig)
{
struct at_dma_chan *atchan = to_at_dma_chan(chan);

+ dev_vdbg(chan2dev(chan), "%s\n", __func__);
+
/* Check if it is chan is configured for slave transfers */
if (!chan->private)
return -EINVAL;
@@ -989,9 +991,28 @@ static int set_runtime_config(struct dma_chan *chan,
return 0;
}

+static int atc_pause(struct dma_chan *chan)
+{
+ struct at_dma_chan *atchan = to_at_dma_chan(chan);
+ struct at_dma *atdma = to_at_dma(chan->device);
+ int chan_id = atchan->chan_common.chan_id;
+ unsigned long flags;

-static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
- unsigned long arg)
+ LIST_HEAD(list);
+
+ dev_vdbg(chan2dev(chan), "%s\n", __func__);
+
+ spin_lock_irqsave(&atchan->lock, flags);
+
+ dma_writel(atdma, CHER, AT_DMA_SUSP(chan_id));
+ set_bit(ATC_IS_PAUSED, &atchan->status);
+
+ spin_unlock_irqrestore(&atchan->lock, flags);
+
+ return 0;
+}
+
+static int atc_resume(struct dma_chan *chan)
{
struct at_dma_chan *atchan = to_at_dma_chan(chan);
struct at_dma *atdma = to_at_dma(chan->device);
@@ -1000,60 +1021,61 @@ static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,

LIST_HEAD(list);

- dev_vdbg(chan2dev(chan), "atc_control (%d)\n", cmd);
+ dev_vdbg(chan2dev(chan), "%s\n", __func__);

- if (cmd == DMA_PAUSE) {
- spin_lock_irqsave(&atchan->lock, flags);
+ if (!atc_chan_is_paused(atchan))
+ return 0;

- dma_writel(atdma, CHER, AT_DMA_SUSP(chan_id));
- set_bit(ATC_IS_PAUSED, &atchan->status);
+ spin_lock_irqsave(&atchan->lock, flags);

- spin_unlock_irqrestore(&atchan->lock, flags);
- } else if (cmd == DMA_RESUME) {
- if (!atc_chan_is_paused(atchan))
- return 0;
+ dma_writel(atdma, CHDR, AT_DMA_RES(chan_id));
+ clear_bit(ATC_IS_PAUSED, &atchan->status);

- spin_lock_irqsave(&atchan->lock, flags);
+ spin_unlock_irqrestore(&atchan->lock, flags);

- dma_writel(atdma, CHDR, AT_DMA_RES(chan_id));
- clear_bit(ATC_IS_PAUSED, &atchan->status);
+ return 0;
+}

- spin_unlock_irqrestore(&atchan->lock, flags);
- } else if (cmd == DMA_TERMINATE_ALL) {
- struct at_desc *desc, *_desc;
- /*
- * This is only called when something went wrong elsewhere, so
- * we don't really care about the data. Just disable the
- * channel. We still have to poll the channel enable bit due
- * to AHB/HSB limitations.
- */
- spin_lock_irqsave(&atchan->lock, flags);
+static int atc_terminate_all(struct dma_chan *chan)
+{
+ struct at_dma_chan *atchan = to_at_dma_chan(chan);
+ struct at_dma *atdma = to_at_dma(chan->device);
+ int chan_id = atchan->chan_common.chan_id;
+ struct at_desc *desc, *_desc;
+ unsigned long flags;

- /* disabling channel: must also remove suspend state */
- dma_writel(atdma, CHDR, AT_DMA_RES(chan_id) | atchan->mask);
+ LIST_HEAD(list);

- /* confirm that this channel is disabled */
- while (dma_readl(atdma, CHSR) & atchan->mask)
- cpu_relax();
+ dev_vdbg(chan2dev(chan), "%s\n", __func__);

- /* active_list entries will end up before queued entries */
- list_splice_init(&atchan->queue, &list);
- list_splice_init(&atchan->active_list, &list);
+ /*
+ * This is only called when something went wrong elsewhere, so
+ * we don't really care about the data. Just disable the
+ * channel. We still have to poll the channel enable bit due
+ * to AHB/HSB limitations.
+ */
+ spin_lock_irqsave(&atchan->lock, flags);

- /* Flush all pending and queued descriptors */
- list_for_each_entry_safe(desc, _desc, &list, desc_node)
- atc_chain_complete(atchan, desc);
+ /* disabling channel: must also remove suspend state */
+ dma_writel(atdma, CHDR, AT_DMA_RES(chan_id) | atchan->mask);

- clear_bit(ATC_IS_PAUSED, &atchan->status);
- /* if channel dedicated to cyclic operations, free it */
- clear_bit(ATC_IS_CYCLIC, &atchan->status);
+ /* confirm that this channel is disabled */
+ while (dma_readl(atdma, CHSR) & atchan->mask)
+ cpu_relax();

- spin_unlock_irqrestore(&atchan->lock, flags);
- } else if (cmd == DMA_SLAVE_CONFIG) {
- return set_runtime_config(chan, (struct dma_slave_config *)arg);
- } else {
- return -ENXIO;
- }
+ /* active_list entries will end up before queued entries */
+ list_splice_init(&atchan->queue, &list);
+ list_splice_init(&atchan->active_list, &list);
+
+ /* Flush all pending and queued descriptors */
+ list_for_each_entry_safe(desc, _desc, &list, desc_node)
+ atc_chain_complete(atchan, desc);
+
+ clear_bit(ATC_IS_PAUSED, &atchan->status);
+ /* if channel dedicated to cyclic operations, free it */
+ clear_bit(ATC_IS_CYCLIC, &atchan->status);
+
+ spin_unlock_irqrestore(&atchan->lock, flags);

return 0;
}
@@ -1505,7 +1527,10 @@ static int __init at_dma_probe(struct platform_device *pdev)
/* controller can do slave DMA: can trigger cyclic transfers */
dma_cap_set(DMA_CYCLIC, atdma->dma_common.cap_mask);
atdma->dma_common.device_prep_dma_cyclic = atc_prep_dma_cyclic;
- atdma->dma_common.device_control = atc_control;
+ atdma->dma_common.device_config = atc_config;
+ atdma->dma_common.device_pause = atc_pause;
+ atdma->dma_common.device_resume = atc_resume;
+ atdma->dma_common.device_terminate_all = atc_terminate_all;
}

dma_writel(atdma, EN, AT_DMA_ENABLE);
@@ -1622,7 +1647,7 @@ static void atc_suspend_cyclic(struct at_dma_chan *atchan)
if (!atc_chan_is_paused(atchan)) {
dev_warn(chan2dev(chan),
"cyclic channel not paused, should be done by channel user\n");
- atc_control(chan, DMA_PAUSE, 0);
+ atc_pause(chan);
}

/* now preserve additional data for cyclic operations */
--
2.1.1

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