Patch "ARM: OMAP1: DMA: Correct the number of logical channels" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

ARM: OMAP1: DMA: Correct the number of logical channels

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
arm-omap1-dma-correct-the-number-of-logical-channels.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Peter Ujfalusi <[email protected]>
Date: Tue, 3 Jan 2017 13:22:34 +0200
Subject: ARM: OMAP1: DMA: Correct the number of logical channels

From: Peter Ujfalusi <[email protected]>

[ Upstream commit 657279778af54f35e54b07b6687918f254a2992c ]

OMAP1510, OMAP5910 and OMAP310 have only 9 logical channels. OMAP1610, OMAP5912, OMAP1710, OMAP730, and OMAP850 have 16 logical channels available.

The wired 17 for the lch_count must have been used to cover the 16 + 1 dedicated LCD channel, in reality we can only use 9 or 16 channels.

The d->chan_count is not used by the omap-dma stack, so we can skip the setup. chan_count was configured to the number of logical channels and not the actual number of physical channels anyways.

---
 arch/arm/mach-omap1/dma.c |   16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

@@ -31,7 +31,6 @@
 #include "soc.h"
 
 #define OMAP1_DMA_BASE			(0xfffed800)
-#define OMAP1_LOGICAL_DMA_CH_COUNT	17
 
 static u32 enable_1510_mode;
 

@@ -311,8 +310,6 @@ static int __init omap1_system_dma_init(
 		goto exit_iounmap;
 	}
 
-	d->lch_count		= OMAP1_LOGICAL_DMA_CH_COUNT;
-
 	/* Valid attributes for omap1 plus processors */
 	if (cpu_is_omap15xx())
 		d->dev_caps = ENABLE_1510_MODE;

@@ -329,13 +326,14 @@ static int __init omap1_system_dma_init(
 	d->dev_caps		|= CLEAR_CSR_ON_READ;
 	d->dev_caps		|= IS_WORD_16;
 
-	if (cpu_is_omap15xx())
-		d->chan_count = 9;
-	else if (cpu_is_omap16xx() || cpu_is_omap7xx()) {
-		if (!(d->dev_caps & ENABLE_1510_MODE))
-			d->chan_count = 16;
+	/* available logical channels */
+	if (cpu_is_omap15xx()) {
+		d->lch_count = 9;
+	} else {
+		if (d->dev_caps & ENABLE_1510_MODE)
+			d->lch_count = 9;
 		else
-			d->chan_count = 9;
+			d->lch_count = 16;
 	}
 
 	p = dma_plat_info;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/arm-omap1-dma-correct-the-number-of-logical-channels.patch