brcmfmac: Use atomic functions for intstatus update.

The intstatus in sdio code can be updated from different
threads. To protect intstatus access, atomic functions are
used. The loop was replaced using atomic_set_mask().

Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Reviewed-by: Daniel (Deognyoun) Kim <dekim@broadcom.com>
Signed-off-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c

@@ -2449,7 +2449,7 @@ static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
 	struct brcmf_core *buscore;
 	u32 addr;
 	unsigned long val;
-	int n, ret;
+	int ret;
 
 	buscore = brcmf_chip_get_core(bus->ci, BCMA_CORE_SDIO_DEV);
 	addr = buscore->base + offsetof(struct sdpcmd_regs, intstatus);
@@ -2457,7 +2457,7 @@ static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
 	val = brcmf_sdiod_regrl(bus->sdiodev, addr, &ret);
 	bus->sdcnt.f1regdata++;
 	if (ret != 0)
-		val = 0;
+		return ret;
 
 	val &= bus->hostintmask;
 	atomic_set(&bus->fcstate, !!(val & I_HMB_FC_STATE));
@@ -2466,13 +2466,7 @@ static int brcmf_sdio_intr_rstatus(struct brcmf_sdio *bus)
 	if (val) {
 		brcmf_sdiod_regwl(bus->sdiodev, addr, val, &ret);
 		bus->sdcnt.f1regdata++;
-	}
-
-	if (ret) {
-		atomic_set(&bus->intstatus, 0);
-	} else if (val) {
-		for_each_set_bit(n, &val, 32)
-			set_bit(n, (unsigned long *)&bus->intstatus.counter);
+		atomic_set_mask(val, &bus->intstatus);
 	}
 
 	return ret;
@@ -2484,7 +2478,7 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
 	unsigned long intstatus;
 	uint txlimit = bus->txbound;	/* Tx frames to send before resched */
 	uint framecnt;			/* Temporary counter of tx/rx frames */
-	int err = 0, n;
+	int err = 0;
 
 	brcmf_dbg(TRACE, "Enter\n");
 
@@ -2588,10 +2582,8 @@ static void brcmf_sdio_dpc(struct brcmf_sdio *bus)
 	}
 
 	/* Keep still-pending events for next scheduling */
-	if (intstatus) {
-		for_each_set_bit(n, &intstatus, 32)
-			set_bit(n, (unsigned long *)&bus->intstatus.counter);
-	}
+	if (intstatus)
+		atomic_set_mask(intstatus, &bus->intstatus);
 
 	brcmf_sdio_clrintr(bus);