ath6kl: Workaround to support Deep Sleep with MSM.

Set the host pm flag MMC_PM_WAKE_SDIO_IRQ to allow host
to disable the sdc2_clk and sdc2_h_clk,so that the MSM device
enter into TCXO shutdown.
Signed-off-by: Santosh Sajjan <ssajjan@codeaurora.org>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath6kl/sdio.c

@@ -856,6 +856,19 @@ static int ath6kl_sdio_suspend(struct ath6kl *ar, struct cfg80211_wowlan *wow)
 		if (ret)
 			goto cut_pwr;
 
+		/*
+		 * Workaround to support Deep Sleep with MSM, set the host pm
+		 * flag as MMC_PM_WAKE_SDIO_IRQ to allow SDCC deiver to disable
+		 * the sdc2_clock and internally allows MSM to enter
+		 * TCXO shutdown properly.
+		 */
+		if ((flags & MMC_PM_WAKE_SDIO_IRQ)) {
+			ret = sdio_set_host_pm_flags(func,
+						MMC_PM_WAKE_SDIO_IRQ);
+			if (ret)
+				goto cut_pwr;
+		}
+
 		ret = ath6kl_cfg80211_suspend(ar, ATH6KL_CFG_SUSPEND_DEEPSLEEP,
 					      NULL);
 		if (ret)