rtlwifi: rtl8192se: Use write barrier when assigning ownership

As noted by Mike McCormack <mikem@ring3k.org> for rtl8192ce, make sure
all updates to a descriptor are flushed to memory before assigning ownship
to hardware.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/rtlwifi/rtl8192se/trx.c b/drivers/net/wireless/rtlwifi/rtl8192se/trx.c
index 14a8b78..d509cf6 100644 (file)
--- a/drivers/net/wireless/rtlwifi/rtl8192se/trx.c
+++ b/drivers/net/wireless/rtlwifi/rtl8192se/trx.c
@@ -873,6 +873,7 @@ void rtl92se_tx_fill_cmddesc(struct ieee80211_hw *hw, u8 *pdesc,
                SET_TX_DESC_TX_BUFFER_SIZE(pdesc, (u16)(skb->len));
                SET_TX_DESC_TX_BUFFER_ADDRESS(pdesc, cpu_to_le32(mapping));
 
+               wmb();
                SET_TX_DESC_OWN(pdesc, 1);
        } else { /* H2C Command Desc format (Host TXCMD) */
                /* 92SE must set as 1 for firmware download HW DMA error */
@@ -891,6 +892,7 @@ void rtl92se_tx_fill_cmddesc(struct ieee80211_hw *hw, u8 *pdesc,
                SET_TX_DESC_TX_BUFFER_SIZE(pdesc, (u16)(skb->len));
                SET_TX_DESC_TX_BUFFER_ADDRESS(pdesc, cpu_to_le32(mapping));
 
+               wmb();
                SET_TX_DESC_OWN(pdesc, 1);
 
        }
@@ -901,6 +903,7 @@ void rtl92se_set_desc(u8 *pdesc, bool istx, u8 desc_name, u8 *val)
        if (istx == true) {
                switch (desc_name) {
                case HW_DESC_OWN:
+                       wmb();
                        SET_TX_DESC_OWN(pdesc, 1);
                        break;
                case HW_DESC_TX_NEXTDESC_ADDR:
@@ -914,6 +917,7 @@ void rtl92se_set_desc(u8 *pdesc, bool istx, u8 desc_name, u8 *val)
        } else {
                switch (desc_name) {
                case HW_DESC_RXOWN:
+                       wmb();
                        SET_RX_STATUS_DESC_OWN(pdesc, 1);
                        break;
                case HW_DESC_RXBUFF_ADDR: