[source] ath9k: remove old rx dma stop check optimization

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/00ad43f047746ab16c6558306de8ab8265b4f9f1

commit 00ad43f047746ab16c6558306de8ab8265b4f9f1
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Tue Dec 27 12:10:53 2016 +0100

    ath9k: remove old rx dma stop check optimization
    
    This commit was added to improve reset time on old SoC devices that run
    into chip hangs more frequently. However with the more recent addition
    of full WMAC reset on these chips, it could be problematic.
    Drop this patch to ensure that DMA activity is really stopped before the
    chip reset is issued
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 .../patches/541-ath9k_rx_dma_stop_check.patch      | 28 ----------------------
 1 file changed, 28 deletions(-)

diff --git a/package/kernel/mac80211/patches/541-ath9k_rx_dma_stop_check.patch b/package/kernel/mac80211/patches/541-ath9k_rx_dma_stop_check.patch
deleted file mode 100644
index c2d2781..0000000
--- a/package/kernel/mac80211/patches/541-ath9k_rx_dma_stop_check.patch
+++ /dev/null
@@ -1,28 +0,0 @@
---- a/drivers/net/wireless/ath/ath9k/mac.c
-+++ b/drivers/net/wireless/ath/ath9k/mac.c
-@@ -698,7 +698,7 @@ bool ath9k_hw_stopdmarecv(struct ath_hw
- {
- #define AH_RX_STOP_DMA_TIMEOUT 10000   /* usec */
- 	struct ath_common *common = ath9k_hw_common(ah);
--	u32 mac_status, last_mac_status = 0;
-+	u32 mac_status = 0, last_mac_status = 0;
- 	int i;
- 
- 	/* Enable access to the DMA observation bus */
-@@ -728,6 +728,16 @@ bool ath9k_hw_stopdmarecv(struct ath_hw
- 	}
- 
- 	if (i == 0) {
-+		if (!AR_SREV_9300_20_OR_LATER(ah) &&
-+		    (mac_status & 0x700) == 0) {
-+			/*
-+			 * DMA is idle but the MAC is still stuck
-+			 * processing events
-+			 */
-+			*reset = true;
-+			return true;
-+		}
-+
- 		ath_err(common,
- 			"DMA failed to stop in %d ms AR_CR=0x%08x AR_DIAG_SW=0x%08x DMADBG_7=0x%08x\n",
- 			AH_RX_STOP_DMA_TIMEOUT / 1000,