rtl8xxxu: Make DMA aggregation optional by setting a module parameter

Let the default to off until we have more data on the right default
tuning values.

Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

diff --git a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
index fb0e5b9063d890232c2ba0798a36fc138bbc3d1a..33e2909941af1cbf33d7434ae55fed96c6ed95e7 100644 (file)
--- a/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
+++ b/drivers/net/wireless/realtek/rtl8xxxu/rtl8xxxu_core.c
@@ -44,6 +44,7 @@
 
 int rtl8xxxu_debug = RTL8XXXU_DEBUG_EFUSE;
 static bool rtl8xxxu_ht40_2g;
+static bool rtl8xxxu_dma_aggregation;
 
 MODULE_AUTHOR("Jes Sorensen <Jes.Sorensen@redhat.com>");
 MODULE_DESCRIPTION("RTL8XXXu USB mac80211 Wireless LAN Driver");
@@ -62,6 +63,8 @@ module_param_named(debug, rtl8xxxu_debug, int, 0600);
 MODULE_PARM_DESC(debug, "Set debug mask");
 module_param_named(ht40_2g, rtl8xxxu_ht40_2g, bool, 0600);
 MODULE_PARM_DESC(ht40_2g, "Enable HT40 support on the 2.4GHz band");
+module_param_named(dma_aggregation, rtl8xxxu_dma_aggregation, bool, 0600);
+MODULE_PARM_DESC(dma_aggregation, "Enable DMA packet aggregation");
 
 #define USB_VENDOR_ID_REALTEK          0x0bda
 #define RTL8XXXU_RX_URBS               32
@@ -4411,14 +4414,18 @@ void rtl8xxxu_gen1_init_aggregation(struct rtl8xxxu_priv *priv)
 
        usb_spec = rtl8xxxu_read8(priv, REG_USB_SPECIAL_OPTION);
        usb_spec &= ~USB_SPEC_USB_AGG_ENABLE;
+       rtl8xxxu_write8(priv, REG_USB_SPECIAL_OPTION, usb_spec);
 
        agg_ctrl = rtl8xxxu_read8(priv, REG_TRXDMA_CTRL);
        agg_ctrl &= ~TRXDMA_CTRL_RXDMA_AGG_EN;
 
-       agg_ctrl |= TRXDMA_CTRL_RXDMA_AGG_EN;
+       if (!rtl8xxxu_dma_aggregation) {
+               rtl8xxxu_write8(priv, REG_TRXDMA_CTRL, agg_ctrl);
+               return;
+       }
 
+       agg_ctrl |= TRXDMA_CTRL_RXDMA_AGG_EN;
        rtl8xxxu_write8(priv, REG_TRXDMA_CTRL, agg_ctrl);
-       rtl8xxxu_write8(priv, REG_USB_SPECIAL_OPTION, usb_spec);
 
        /*
         * The number of packets we can take looks to be buffer size / 512