[PATCH] ARM: OMAP1: DMA: Correct the number of logical channels

Peter Ujfalusi peter.ujfalusi at ti.com
Tue Jan 3 03:22:34 PST 2017


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.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi at ti.com>
---
 arch/arm/mach-omap1/dma.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/arch/arm/mach-omap1/dma.c b/arch/arm/mach-omap1/dma.c
index f6ba589cd312..c821c1d5610e 100644
--- a/arch/arm/mach-omap1/dma.c
+++ b/arch/arm/mach-omap1/dma.c
@@ -32,7 +32,6 @@
 #include "soc.h"
 
 #define OMAP1_DMA_BASE			(0xfffed800)
-#define OMAP1_LOGICAL_DMA_CH_COUNT	17
 
 static u32 enable_1510_mode;
 
@@ -348,8 +347,6 @@ static int __init omap1_system_dma_init(void)
 		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;
@@ -366,13 +363,14 @@ static int __init omap1_system_dma_init(void)
 	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;
-- 
2.11.0




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