async_tx: make async_tx channel switching opt-in
The majority of drivers in drivers/dma/ will never establish cross
channel operation chains and do not need the extra overhead in struct
dma_async_tx_descriptor. Make channel switching opt-in by default.
Cc: Anatolij Gustschin <agust@denx.de>
Cc: Ira Snyder <iws@ovro.caltech.edu>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Saeed Bishara <saeed@marvell.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index ab28f60..79d1542 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -46,7 +46,7 @@
If unsure, say N.
-config ASYNC_TX_DISABLE_CHANNEL_SWITCH
+config ASYNC_TX_ENABLE_CHANNEL_SWITCH
bool
config AMBA_PL08X
@@ -62,7 +62,6 @@
depends on PCI && X86
select DMA_ENGINE
select DCA
- select ASYNC_TX_DISABLE_CHANNEL_SWITCH
select ASYNC_TX_DISABLE_PQ_VAL_DMA
select ASYNC_TX_DISABLE_XOR_VAL_DMA
help
@@ -77,6 +76,7 @@
tristate "Intel IOP ADMA support"
depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_IOP13XX
select DMA_ENGINE
+ select ASYNC_TX_ENABLE_CHANNEL_SWITCH
help
Enable support for the Intel(R) IOP Series RAID engines.
@@ -101,6 +101,7 @@
tristate "Freescale Elo and Elo Plus DMA support"
depends on FSL_SOC
select DMA_ENGINE
+ select ASYNC_TX_ENABLE_CHANNEL_SWITCH
---help---
Enable support for the Freescale Elo and Elo Plus DMA controllers.
The Elo is the DMA controller on some 82xx and 83xx parts, and the
@@ -117,6 +118,7 @@
bool "Marvell XOR engine support"
depends on PLAT_ORION
select DMA_ENGINE
+ select ASYNC_TX_ENABLE_CHANNEL_SWITCH
---help---
Enable support for the Marvell XOR engine.
@@ -174,6 +176,7 @@
depends on 440SPe || 440SP
select DMA_ENGINE
select ARCH_HAS_ASYNC_TX_FIND_CHANNEL
+ select ASYNC_TX_ENABLE_CHANNEL_SWITCH
help
Enable support for the AMCC PPC440SPe RAID engines.