From e2346677af86150c6083974585c131e8a2c3ddcc Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 6 Jan 2009 11:38:21 -0700 Subject: [PATCH] dmaengine: advertise all channels on a device to dma_filter_fn Allow dma_filter_fn routines to disambiguate multiple channels on a device rather than assuming that all channels on a device are equal. Cc: Maciej Sosnowski Reported-by: Guennadi Liakhovetski Signed-off-by: Dan Williams --- drivers/dma/dmaengine.c | 33 +++++++++++++-------------------- 1 file changed, 13 insertions(+), 20 deletions(-) diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c index dd43410c1019..9d3594cf17e0 100644 --- a/drivers/dma/dmaengine.c +++ b/drivers/dma/dmaengine.c @@ -454,10 +454,10 @@ static void dma_channel_rebalance(void) } } -static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_device *dev) +static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_device *dev, + dma_filter_fn fn, void *fn_param) { struct dma_chan *chan; - struct dma_chan *ret = NULL; if (!__dma_device_satisfies_mask(dev, mask)) { pr_debug("%s: wrong capabilities\n", __func__); @@ -479,11 +479,15 @@ static struct dma_chan *private_candidate(dma_cap_mask_t *mask, struct dma_devic __func__, dma_chan_name(chan)); continue; } - ret = chan; - break; + if (fn && !fn(chan, fn_param)) { + pr_debug("%s: %s filter said false\n", + __func__, dma_chan_name(chan)); + continue; + } + return chan; } - return ret; + return NULL; } /** @@ -496,22 +500,13 @@ struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, v { struct dma_device *device, *_d; struct dma_chan *chan = NULL; - bool ack; 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); - if (!chan) - continue; - - if (fn) - ack = fn(chan, fn_param); - else - ack = true; - - if (ack) { + 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 @@ -529,10 +524,8 @@ struct dma_chan *__dma_request_channel(dma_cap_mask_t *mask, dma_filter_fn fn, v dma_chan_name(chan), err); else break; - } else - pr_debug("%s: %s filter said false\n", - __func__, dma_chan_name(chan)); - chan = NULL; + chan = NULL; + } } mutex_unlock(&dma_list_mutex); -- 2.20.1