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path: root/drivers/dma/at_hdmac.c
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Diffstat (limited to 'drivers/dma/at_hdmac.c')
-rw-r--r--drivers/dma/at_hdmac.c164
1 files changed, 127 insertions, 37 deletions
diff --git a/drivers/dma/at_hdmac.c b/drivers/dma/at_hdmac.c
index 6a483ea..fcfa0a8 100644
--- a/drivers/dma/at_hdmac.c
+++ b/drivers/dma/at_hdmac.c
@@ -107,10 +107,11 @@ static struct at_desc *atc_desc_get(struct at_dma_chan *atchan)
{
struct at_desc *desc, *_desc;
struct at_desc *ret = NULL;
+ unsigned long flags;
unsigned int i = 0;
LIST_HEAD(tmp_list);
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
list_for_each_entry_safe(desc, _desc, &atchan->free_list, desc_node) {
i++;
if (async_tx_test_ack(&desc->txd)) {
@@ -121,7 +122,7 @@ static struct at_desc *atc_desc_get(struct at_dma_chan *atchan)
dev_dbg(chan2dev(&atchan->chan_common),
"desc %p not ACKed\n", desc);
}
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
dev_vdbg(chan2dev(&atchan->chan_common),
"scanned %u descriptors on freelist\n", i);
@@ -129,9 +130,9 @@ static struct at_desc *atc_desc_get(struct at_dma_chan *atchan)
if (!ret) {
ret = atc_alloc_descriptor(&atchan->chan_common, GFP_ATOMIC);
if (ret) {
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
atchan->descs_allocated++;
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
} else {
dev_err(chan2dev(&atchan->chan_common),
"not enough descriptors available\n");
@@ -150,8 +151,9 @@ static void atc_desc_put(struct at_dma_chan *atchan, struct at_desc *desc)
{
if (desc) {
struct at_desc *child;
+ unsigned long flags;
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
list_for_each_entry(child, &desc->tx_list, desc_node)
dev_vdbg(chan2dev(&atchan->chan_common),
"moving child desc %p to freelist\n",
@@ -160,7 +162,7 @@ static void atc_desc_put(struct at_dma_chan *atchan, struct at_desc *desc)
dev_vdbg(chan2dev(&atchan->chan_common),
"moving desc %p to freelist\n", desc);
list_add(&desc->desc_node, &atchan->free_list);
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
}
}
@@ -299,7 +301,7 @@ atc_chain_complete(struct at_dma_chan *atchan, struct at_desc *desc)
/* for cyclic transfers,
* no need to replay callback function while stopping */
- if (!test_bit(ATC_IS_CYCLIC, &atchan->status)) {
+ if (!atc_chan_is_cyclic(atchan)) {
dma_async_tx_callback callback = txd->callback;
void *param = txd->callback_param;
@@ -471,16 +473,17 @@ static void atc_handle_cyclic(struct at_dma_chan *atchan)
static void atc_tasklet(unsigned long data)
{
struct at_dma_chan *atchan = (struct at_dma_chan *)data;
+ unsigned long flags;
- spin_lock(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
if (test_and_clear_bit(ATC_IS_ERROR, &atchan->status))
atc_handle_error(atchan);
- else if (test_bit(ATC_IS_CYCLIC, &atchan->status))
+ else if (atc_chan_is_cyclic(atchan))
atc_handle_cyclic(atchan);
else
atc_advance_work(atchan);
- spin_unlock(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
}
static irqreturn_t at_dma_interrupt(int irq, void *dev_id)
@@ -539,8 +542,9 @@ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx)
struct at_desc *desc = txd_to_at_desc(tx);
struct at_dma_chan *atchan = to_at_dma_chan(tx->chan);
dma_cookie_t cookie;
+ unsigned long flags;
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
cookie = atc_assign_cookie(atchan, desc);
if (list_empty(&atchan->active_list)) {
@@ -554,7 +558,7 @@ static dma_cookie_t atc_tx_submit(struct dma_async_tx_descriptor *tx)
list_add_tail(&desc->desc_node, &atchan->queue);
}
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
return cookie;
}
@@ -927,28 +931,29 @@ static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
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;
LIST_HEAD(list);
dev_vdbg(chan2dev(chan), "atc_control (%d)\n", cmd);
if (cmd == DMA_PAUSE) {
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
dma_writel(atdma, CHER, AT_DMA_SUSP(chan_id));
set_bit(ATC_IS_PAUSED, &atchan->status);
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
} else if (cmd == DMA_RESUME) {
- if (!test_bit(ATC_IS_PAUSED, &atchan->status))
+ if (!atc_chan_is_paused(atchan))
return 0;
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
dma_writel(atdma, CHDR, AT_DMA_RES(chan_id));
clear_bit(ATC_IS_PAUSED, &atchan->status);
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
} else if (cmd == DMA_TERMINATE_ALL) {
struct at_desc *desc, *_desc;
/*
@@ -957,7 +962,7 @@ static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
* channel. We still have to poll the channel enable bit due
* to AHB/HSB limitations.
*/
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
/* disabling channel: must also remove suspend state */
dma_writel(atdma, CHDR, AT_DMA_RES(chan_id) | atchan->mask);
@@ -978,7 +983,7 @@ static int atc_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd,
/* if channel dedicated to cyclic operations, free it */
clear_bit(ATC_IS_CYCLIC, &atchan->status);
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
} else {
return -ENXIO;
}
@@ -1004,9 +1009,10 @@ atc_tx_status(struct dma_chan *chan,
struct at_dma_chan *atchan = to_at_dma_chan(chan);
dma_cookie_t last_used;
dma_cookie_t last_complete;
+ unsigned long flags;
enum dma_status ret;
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
last_complete = atchan->completed_cookie;
last_used = chan->cookie;
@@ -1021,7 +1027,7 @@ atc_tx_status(struct dma_chan *chan,
ret = dma_async_is_complete(cookie, last_complete, last_used);
}
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
if (ret != DMA_SUCCESS)
dma_set_tx_state(txstate, last_complete, last_used,
@@ -1029,7 +1035,7 @@ atc_tx_status(struct dma_chan *chan,
else
dma_set_tx_state(txstate, last_complete, last_used, 0);
- if (test_bit(ATC_IS_PAUSED, &atchan->status))
+ if (atc_chan_is_paused(atchan))
ret = DMA_PAUSED;
dev_vdbg(chan2dev(chan), "tx_status %d: cookie = %d (d%d, u%d)\n",
@@ -1046,18 +1052,19 @@ atc_tx_status(struct dma_chan *chan,
static void atc_issue_pending(struct dma_chan *chan)
{
struct at_dma_chan *atchan = to_at_dma_chan(chan);
+ unsigned long flags;
dev_vdbg(chan2dev(chan), "issue_pending\n");
/* Not needed for cyclic transfers */
- if (test_bit(ATC_IS_CYCLIC, &atchan->status))
+ if (atc_chan_is_cyclic(atchan))
return;
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
if (!atc_chan_is_enabled(atchan)) {
atc_advance_work(atchan);
}
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
}
/**
@@ -1073,6 +1080,7 @@ static int atc_alloc_chan_resources(struct dma_chan *chan)
struct at_dma *atdma = to_at_dma(chan->device);
struct at_desc *desc;
struct at_dma_slave *atslave;
+ unsigned long flags;
int i;
u32 cfg;
LIST_HEAD(tmp_list);
@@ -1116,11 +1124,11 @@ static int atc_alloc_chan_resources(struct dma_chan *chan)
list_add_tail(&desc->desc_node, &tmp_list);
}
- spin_lock_bh(&atchan->lock);
+ spin_lock_irqsave(&atchan->lock, flags);
atchan->descs_allocated = i;
list_splice(&tmp_list, &atchan->free_list);
atchan->completed_cookie = chan->cookie = 1;
- spin_unlock_bh(&atchan->lock);
+ spin_unlock_irqrestore(&atchan->lock, flags);
/* channel parameters */
channel_writel(atchan, CFG, cfg);
@@ -1260,12 +1268,11 @@ static int __init at_dma_probe(struct platform_device *pdev)
/* initialize channels related values */
INIT_LIST_HEAD(&atdma->dma_common.channels);
- for (i = 0; i < pdata->nr_channels; i++, atdma->dma_common.chancnt++) {
+ for (i = 0; i < pdata->nr_channels; i++) {
struct at_dma_chan *atchan = &atdma->chan[i];
atchan->chan_common.device = &atdma->dma_common;
atchan->chan_common.cookie = atchan->completed_cookie = 1;
- atchan->chan_common.chan_id = i;
list_add_tail(&atchan->chan_common.device_node,
&atdma->dma_common.channels);
@@ -1293,22 +1300,20 @@ static int __init at_dma_probe(struct platform_device *pdev)
if (dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask))
atdma->dma_common.device_prep_dma_memcpy = atc_prep_dma_memcpy;
- if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask))
+ if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask)) {
atdma->dma_common.device_prep_slave_sg = atc_prep_slave_sg;
-
- if (dma_has_cap(DMA_CYCLIC, atdma->dma_common.cap_mask))
+ /* 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;
-
- if (dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask) ||
- dma_has_cap(DMA_CYCLIC, atdma->dma_common.cap_mask))
atdma->dma_common.device_control = atc_control;
+ }
dma_writel(atdma, EN, AT_DMA_ENABLE);
dev_info(&pdev->dev, "Atmel AHB DMA Controller ( %s%s), %d channels\n",
dma_has_cap(DMA_MEMCPY, atdma->dma_common.cap_mask) ? "cpy " : "",
dma_has_cap(DMA_SLAVE, atdma->dma_common.cap_mask) ? "slave " : "",
- atdma->dma_common.chancnt);
+ pdata->nr_channels);
dma_async_device_register(&atdma->dma_common);
@@ -1377,27 +1382,112 @@ static void at_dma_shutdown(struct platform_device *pdev)
clk_disable(atdma->clk);
}
+static int at_dma_prepare(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct at_dma *atdma = platform_get_drvdata(pdev);
+ struct dma_chan *chan, *_chan;
+
+ list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels,
+ device_node) {
+ struct at_dma_chan *atchan = to_at_dma_chan(chan);
+ /* wait for transaction completion (except in cyclic case) */
+ if (atc_chan_is_enabled(atchan) && !atc_chan_is_cyclic(atchan))
+ return -EAGAIN;
+ }
+ return 0;
+}
+
+static void atc_suspend_cyclic(struct at_dma_chan *atchan)
+{
+ struct dma_chan *chan = &atchan->chan_common;
+
+ /* Channel should be paused by user
+ * do it anyway even if it is not done already */
+ 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);
+ }
+
+ /* now preserve additional data for cyclic operations */
+ /* next descriptor address in the cyclic list */
+ atchan->save_dscr = channel_readl(atchan, DSCR);
+
+ vdbg_dump_regs(atchan);
+}
+
static int at_dma_suspend_noirq(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct at_dma *atdma = platform_get_drvdata(pdev);
+ struct dma_chan *chan, *_chan;
- at_dma_off(platform_get_drvdata(pdev));
+ /* preserve data */
+ list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels,
+ device_node) {
+ struct at_dma_chan *atchan = to_at_dma_chan(chan);
+
+ if (atc_chan_is_cyclic(atchan))
+ atc_suspend_cyclic(atchan);
+ atchan->save_cfg = channel_readl(atchan, CFG);
+ }
+ atdma->save_imr = dma_readl(atdma, EBCIMR);
+
+ /* disable DMA controller */
+ at_dma_off(atdma);
clk_disable(atdma->clk);
return 0;
}
+static void atc_resume_cyclic(struct at_dma_chan *atchan)
+{
+ struct at_dma *atdma = to_at_dma(atchan->chan_common.device);
+
+ /* restore channel status for cyclic descriptors list:
+ * next descriptor in the cyclic list at the time of suspend */
+ channel_writel(atchan, SADDR, 0);
+ channel_writel(atchan, DADDR, 0);
+ channel_writel(atchan, CTRLA, 0);
+ channel_writel(atchan, CTRLB, 0);
+ channel_writel(atchan, DSCR, atchan->save_dscr);
+ dma_writel(atdma, CHER, atchan->mask);
+
+ /* channel pause status should be removed by channel user
+ * We cannot take the initiative to do it here */
+
+ vdbg_dump_regs(atchan);
+}
+
static int at_dma_resume_noirq(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct at_dma *atdma = platform_get_drvdata(pdev);
+ struct dma_chan *chan, *_chan;
+ /* bring back DMA controller */
clk_enable(atdma->clk);
dma_writel(atdma, EN, AT_DMA_ENABLE);
+
+ /* clear any pending interrupt */
+ while (dma_readl(atdma, EBCISR))
+ cpu_relax();
+
+ /* restore saved data */
+ dma_writel(atdma, EBCIER, atdma->save_imr);
+ list_for_each_entry_safe(chan, _chan, &atdma->dma_common.channels,
+ device_node) {
+ struct at_dma_chan *atchan = to_at_dma_chan(chan);
+
+ channel_writel(atchan, CFG, atchan->save_cfg);
+ if (atc_chan_is_cyclic(atchan))
+ atc_resume_cyclic(atchan);
+ }
return 0;
}
static const struct dev_pm_ops at_dma_dev_pm_ops = {
+ .prepare = at_dma_prepare,
.suspend_noirq = at_dma_suspend_noirq,
.resume_noirq = at_dma_resume_noirq,
};
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