libertas: check whether bus can do more than polling

If a sdio host does not support sdio irqs, polling is used
instead. That has an impact on performance. Some functionality
should not be enabled then. This add a variable in
libertas_priv to indicate that.

Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

drivers/net/wireless/marvell/libertas/dev.h

@@ -99,6 +99,7 @@ struct lbs_private {
 	/* Hardware access */
 	void *card;
 	bool iface_running;
+	u8 is_polling; /* host has to poll the card irq */
 	u8 fw_ready;
 	u8 surpriseremoved;
 	u8 setup_fw_on_resume;

drivers/net/wireless/marvell/libertas/if_sdio.c

@@ -1267,7 +1267,7 @@ static int if_sdio_probe(struct sdio_func *func,
 	priv->reset_card = if_sdio_reset_card;
 	priv->power_save = if_sdio_power_save;
 	priv->power_restore = if_sdio_power_restore;
-
+	priv->is_polling = !(func->card->host->caps & MMC_CAP_SDIO_IRQ);
 	ret = if_sdio_power_on(card);
 	if (ret)
 		goto err_activate_card;

drivers/net/wireless/marvell/libertas/if_usb.c

@@ -267,6 +267,7 @@ static int if_usb_probe(struct usb_interface *intf,
 	priv->enter_deep_sleep = NULL;
 	priv->exit_deep_sleep = NULL;
 	priv->reset_deep_sleep_wakeup = NULL;
+	priv->is_polling = false;
 #ifdef CONFIG_OLPC
 	if (machine_is_olpc())
 		priv->reset_card = if_usb_reset_olpc_card;