[PATCH 1/4] usbnet: smsc95xx: add kconfig for turbo mode

[Ben Dooks <ben.dooks@codethink.co.uk>]

Add a configuration option for the default state of turbo mode
on the smsc95xx networking driver. Some systems it is better
to default this to off as it causes significant increases in
soft-irq load.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
---
 drivers/net/usb/Kconfig    | 9 +++++++++
 drivers/net/usb/smsc95xx.c | 2 +-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/drivers/net/usb/Kconfig b/drivers/net/usb/Kconfig
index 418b0904cecb..a32f1a446ce9 100644
--- a/drivers/net/usb/Kconfig
+++ b/drivers/net/usb/Kconfig
@@ -351,6 +351,15 @@ config USB_NET_SMSC95XX
 	  This option adds support for SMSC LAN95XX based USB 2.0
 	  10/100 Ethernet adapters.
 
+config USB_NET_SMSC95XX_TURBO
+	bool "Use turbo receive mode by default"
+	depends on USB_NET_SMSC95XX
+	default y
+	help
+	  This options sets the default turbo mode settings for the
+	  driver's receive path. These can also be altered by the
+	  turbo_mode module parameter.
+
 config USB_NET_GL620A
 	tristate "GeneSys GL620USB-A based cables"
 	depends on USB_USBNET
diff --git a/drivers/net/usb/smsc95xx.c b/drivers/net/usb/smsc95xx.c
index 06b4d290784d..fe13bef9579e 100644
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -78,7 +78,7 @@ struct smsc95xx_priv {
 	struct usbnet *dev;
 };
 
-static bool turbo_mode = true;
+static bool turbo_mode = IS_ENABLED(CONFIG_USB_NET_SMSC95XX_TURBO);
 module_param(turbo_mode, bool, 0644);
 MODULE_PARM_DESC(turbo_mode, "Enable multiple frames per Rx transaction");
 
-- 
2.19.0