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From 7bd903c5ca47fde5ad52370a47776491813c772e Mon Sep 17 00:00:00 2001
From: Peter Ujfalusi <peter.ujfalusi@ti.com>
Date: Mon, 14 Dec 2015 22:47:39 +0200
Subject: [PATCH 1/3] dmaengine: core: Move and merge the code paths using
private_candidate
Channel matching with private_candidate() is used in two paths, the error
checking is slightly different in them and they are duplicating code also.
Move the code under find_candidate() to provide consistent execution and
going to allow us to reuse this mode of channel lookup later.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
---
drivers/dma/dmaengine.c | 81 +++++++++++++++++++++++++------------------------
1 file changed, 42 insertions(+), 39 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index f2cbff9..81a36fc 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -542,6 +542,42 @@ static struct dma_chan *private_candidate(const dma_cap_mask_t *mask,
return NULL;
}
+static struct dma_chan *find_candidate(struct dma_device *device,
+ const dma_cap_mask_t *mask,
+ dma_filter_fn fn, void *fn_param)
+{
+ struct dma_chan *chan = private_candidate(mask, device, fn, fn_param);
+ int err;
+
+ if (chan) {
+ /* Found a suitable channel, try to grab, prep, and return it.
+ * We first set DMA_PRIVATE to disable balance_ref_count as this
+ * channel will not be published in the general-purpose
+ * allocator
+ */
+ dma_cap_set(DMA_PRIVATE, device->cap_mask);
+ device->privatecnt++;
+ err = dma_chan_get(chan);
+
+ if (err) {
+ if (err == -ENODEV) {
+ pr_debug("%s: %s module removed\n", __func__,
+ dma_chan_name(chan));
+ list_del_rcu(&device->global_node);
+ } else
+ pr_debug("%s: failed to get %s: (%d)\n",
+ __func__, dma_chan_name(chan), err);
+
+ if (--device->privatecnt == 0)
+ dma_cap_clear(DMA_PRIVATE, device->cap_mask);
+
+ chan = ERR_PTR(err);
+ }
+ }
+
+ return chan ? chan : ERR_PTR(-EPROBE_DEFER);
+}
+
/**
* dma_get_slave_channel - try to get specific channel exclusively
* @chan: target channel
@@ -580,7 +616,6 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
{
dma_cap_mask_t mask;
struct dma_chan *chan;
- int err;
dma_cap_zero(mask);
dma_cap_set(DMA_SLAVE, mask);
@@ -588,23 +623,11 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
/* lock against __dma_request_channel */
mutex_lock(&dma_list_mutex);
- chan = private_candidate(&mask, device, NULL, NULL);
- if (chan) {
- dma_cap_set(DMA_PRIVATE, device->cap_mask);
- device->privatecnt++;
- err = dma_chan_get(chan);
- if (err) {
- pr_debug("%s: failed to get %s: (%d)\n",
- __func__, dma_chan_name(chan), err);
- chan = NULL;
- if (--device->privatecnt == 0)
- dma_cap_clear(DMA_PRIVATE, device->cap_mask);
- }
- }
+ chan = find_candidate(device, &mask, NULL, NULL);
mutex_unlock(&dma_list_mutex);
- return chan;
+ return IS_ERR(chan) ? NULL : chan;
}
EXPORT_SYMBOL_GPL(dma_get_any_slave_channel);
@@ -621,35 +644,15 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
{
struct dma_device *device, *_d;
struct dma_chan *chan = NULL;
- int err;
/* Find a channel */
mutex_lock(&dma_list_mutex);
list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
- chan = private_candidate(mask, device, fn, fn_param);
- if (chan) {
- /* Found a suitable channel, try to grab, prep, and
- * return it. We first set DMA_PRIVATE to disable
- * balance_ref_count as this channel will not be
- * published in the general-purpose allocator
- */
- dma_cap_set(DMA_PRIVATE, device->cap_mask);
- device->privatecnt++;
- err = dma_chan_get(chan);
+ chan = find_candidate(device, mask, fn, fn_param);
+ if (!IS_ERR(chan))
+ break;
- if (err == -ENODEV) {
- pr_debug("%s: %s module removed\n",
- __func__, dma_chan_name(chan));
- list_del_rcu(&device->global_node);
- } else if (err)
- pr_debug("%s: failed to get %s: (%d)\n",
- __func__, dma_chan_name(chan), err);
- else
- break;
- if (--device->privatecnt == 0)
- dma_cap_clear(DMA_PRIVATE, device->cap_mask);
- chan = NULL;
- }
+ chan = NULL;
}
mutex_unlock(&dma_list_mutex);
--
2.8.1
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