[PATCH v4 4/7] can: Kconfig: add CONFIG_CAN_RX_OFFLOAD

[Vincent Mailhol]

Only a few drivers rely on the CAN rx offload framework (as of the
writing of this patch, only three: flexcan, ti_hecc and
mcp251xfd). Give the option to the user to deselect this features
during compilation.

The drivers relying on CAN rx offload are in different sub
folders. All of these drivers get tagged with "select CAN_RX_OFFLOAD"
so that the option is automatically enabled whenever one of those
driver is chosen.

Signed-off-by: Vincent Mailhol <mailhol.vincent@xxxxxxxxxx>
---
 drivers/net/can/Kconfig               | 16 ++++++++++++++++
 drivers/net/can/dev/Makefile          |  2 ++
 drivers/net/can/spi/mcp251xfd/Kconfig |  1 +
 3 files changed, 19 insertions(+)

diff --git a/drivers/net/can/Kconfig b/drivers/net/can/Kconfig
index 8f3b97aea638..1f1d81da1c8c 100644
--- a/drivers/net/can/Kconfig
+++ b/drivers/net/can/Kconfig
@@ -102,6 +102,20 @@ config CAN_CALC_BITTIMING
 
 	  If unsure, say Y.
 
+config CAN_RX_OFFLOAD
+	bool "CAN RX offload"
+	default y
+	help
+	  Framework to offload the controller's RX FIFO during one
+	  interrupt. The CAN frames of the FIFO are read and put into a skb
+	  queue during that interrupt and transmitted afterwards in a NAPI
+	  context.
+
+	  The additional features selected by this option will be added to the
+	  can-dev module.
+
+	  If unsure, say Y.
+
 config CAN_AT91
 	tristate "Atmel AT91 onchip CAN controller"
 	depends on (ARCH_AT91 || COMPILE_TEST) && HAS_IOMEM
@@ -113,6 +127,7 @@ config CAN_FLEXCAN
 	tristate "Support for Freescale FLEXCAN based chips"
 	depends on OF || COLDFIRE || COMPILE_TEST
 	depends on HAS_IOMEM
+	select CAN_RX_OFFLOAD
 	help
 	  Say Y here if you want to support for Freescale FlexCAN.
 
@@ -162,6 +177,7 @@ config CAN_SUN4I
 config CAN_TI_HECC
 	depends on ARM
 	tristate "TI High End CAN Controller"
+	select CAN_RX_OFFLOAD
 	help
 	  Driver for TI HECC (High End CAN Controller) module found on many
 	  TI devices. The device specifications are available from www.ti.com
diff --git a/drivers/net/can/dev/Makefile b/drivers/net/can/dev/Makefile
index b8a55b1d90cd..5081d8a3be57 100644
--- a/drivers/net/can/dev/Makefile
+++ b/drivers/net/can/dev/Makefile
@@ -11,3 +11,5 @@ can-dev-$(CONFIG_CAN_NETLINK) += netlink.o
 can-dev-$(CONFIG_CAN_NETLINK) += rx-offload.o
 
 can-dev-$(CONFIG_CAN_CALC_BITTIMING) += calc_bittiming.o
+
+can-dev-$(CONFIG_CAN_RX_OFFLOAD) += rx-offload.o
diff --git a/drivers/net/can/spi/mcp251xfd/Kconfig b/drivers/net/can/spi/mcp251xfd/Kconfig
index dd0fc0a54be1..877e4356010d 100644
--- a/drivers/net/can/spi/mcp251xfd/Kconfig
+++ b/drivers/net/can/spi/mcp251xfd/Kconfig
@@ -2,6 +2,7 @@
 
 config CAN_MCP251XFD
 	tristate "Microchip MCP251xFD SPI CAN controllers"
+	select CAN_RX_OFFLOAD
 	select REGMAP
 	select WANT_DEV_COREDUMP
 	help
-- 
2.35.1