ath9k: parse the device configuration from an OF node

This allows setting the MAC address and specifying that the firmware
will be requested from userspace (because there might not be a hardware
EEPROM connected to the chip) for ath9k based PCI devices using
the device tree.

There is some out-of-tree code to "convert devicetree to
ath9k_platform_data" (for example in OpenWrt and LEDE) which becomes
obsolete with this patch.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath9k/init.c

@@ -20,6 +20,8 @@
 #include <linux/slab.h>
 #include <linux/ath9k_platform.h>
 #include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_net.h>
 #include <linux/relay.h>
 #include <net/ieee80211_radiotap.h>
 
@@ -555,6 +557,42 @@ static int ath9k_init_platform(struct ath_softc *sc)
 	return 0;
 }
 
+static int ath9k_of_init(struct ath_softc *sc)
+{
+	struct device_node *np = sc->dev->of_node;
+	struct ath_hw *ah = sc->sc_ah;
+	struct ath_common *common = ath9k_hw_common(ah);
+	enum ath_bus_type bus_type = common->bus_ops->ath_bus_type;
+	const char *mac;
+	char eeprom_name[100];
+	int ret;
+
+	if (!of_device_is_available(np))
+		return 0;
+
+	ath_dbg(common, CONFIG, "parsing configuration from OF node\n");
+
+	if (of_property_read_bool(np, "qca,no-eeprom")) {
+		/* ath9k-eeprom-<bus>-<id>.bin */
+		scnprintf(eeprom_name, sizeof(eeprom_name),
+			  "ath9k-eeprom-%s-%s.bin",
+			  ath_bus_type_to_string(bus_type), dev_name(ah->dev));
+
+		ret = ath9k_eeprom_request(sc, eeprom_name);
+		if (ret)
+			return ret;
+	}
+
+	mac = of_get_mac_address(np);
+	if (mac)
+		ether_addr_copy(common->macaddr, mac);
+
+	ah->ah_flags &= ~AH_USE_EEPROM;
+	ah->ah_flags |= AH_NO_EEP_SWAP;
+
+	return 0;
+}
+
 static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
 			    const struct ath_bus_ops *bus_ops)
 {
@@ -611,6 +649,10 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
 	if (ret)
 		return ret;
 
+	ret = ath9k_of_init(sc);
+	if (ret)
+		return ret;
+
 	if (ath9k_led_active_high != -1)
 		ah->config.led_active_high = ath9k_led_active_high == 1;