4224b52c3a
- random-bcm2708 and spi-bcm2708 have been removed. - sound-soc-bcm2708-i2s has been upstreamed as sound-soc-bcm2835-i2s. Let's keep linux 4.1 for a while, since linux 4.4 appears to have some issues with multicast traffic on RPi ethernet: https://gist.github.com/Noltari/5b1cfdecce5ed4bc08fd Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com> SVN-Revision: 48266
37 lines
1.2 KiB
Diff
37 lines
1.2 KiB
Diff
From c7e464c38d38ad59899c94dfad6c3455c18f7d76 Mon Sep 17 00:00:00 2001
|
|
From: Matthias Reichl <hias@horus.com>
|
|
Date: Sun, 11 Oct 2015 12:28:30 +0200
|
|
Subject: [PATCH 024/127] bcm2835-dma: Limit cyclic transfers on lite channels
|
|
to 32k
|
|
|
|
Transfers larger than 32k cause repeated clicking with I2S soundcards.
|
|
The exact reason is yet unknown, so limit to 32k as bcm2708-dmaengine
|
|
did as an intermediate fix.
|
|
---
|
|
drivers/dma/bcm2835-dma.c | 8 +++++++-
|
|
1 file changed, 7 insertions(+), 1 deletion(-)
|
|
|
|
--- a/drivers/dma/bcm2835-dma.c
|
|
+++ b/drivers/dma/bcm2835-dma.c
|
|
@@ -144,6 +144,12 @@ struct bcm2835_desc {
|
|
*/
|
|
#define MAX_LITE_TRANSFER (SZ_64K - 4)
|
|
|
|
+/*
|
|
+ * Transfers larger than 32k cause issues with the bcm2708-i2s driver,
|
|
+ * so limit transfer size to 32k as bcm2708-dmaengine did.
|
|
+ */
|
|
+#define MAX_CYCLIC_LITE_TRANSFER SZ_32K
|
|
+
|
|
static inline struct bcm2835_dmadev *to_bcm2835_dma_dev(struct dma_device *d)
|
|
{
|
|
return container_of(d, struct bcm2835_dmadev, ddev);
|
|
@@ -412,7 +418,7 @@ static struct dma_async_tx_descriptor *b
|
|
d->c = c;
|
|
d->dir = direction;
|
|
if (c->ch >= 8) /* LITE channel */
|
|
- max_size = MAX_LITE_TRANSFER;
|
|
+ max_size = MAX_CYCLIC_LITE_TRANSFER;
|
|
else
|
|
max_size = MAX_NORMAL_TRANSFER;
|
|
period_len = min(period_len, max_size);
|