Currently SoC platforms use a firmware request to get the EEPROM data.
This is mostly a hack and rely on using a user-helper scripts which is
deprecated. A nicer alternative is to use the nvmem API which was
designed for this kind of task.

Furthermore we let CONFIG_ATH9K_AHB select CONFIG_NVMEM as such
devices will generally use this method for loading the EEPROM data.

Signed-off-by: Alban <albeu@free.fr>
---

@@ -654,6 +656,25 @@ static int ath9k_init_softc(u16 devid, struct ath_softc *sc,
 	if (ret)
 		return ret;
 
+	/* If the EEPROM hasn't been retrieved via firmware request
+	 * use the nvmem API insted.
+	 */
+	if (!ah->eeprom_blob) {
+		struct nvmem_cell *eeprom_cell;
+
+		eeprom_cell = nvmem_cell_get(ah->dev, "eeprom");
+		if (!IS_ERR(eeprom_cell)) {
+			ah->eeprom_data = nvmem_cell_read(
+				eeprom_cell, &ah->eeprom_size);
+			nvmem_cell_put(eeprom_cell);
+
+			if (IS_ERR(ah->eeprom_data)) {
+				dev_err(ah->dev, "failed to read eeprom");
+				return PTR_ERR(ah->eeprom_data);
+			}
+		}
+	}
+
 	if (ath9k_led_active_high != -1)
 		ah->config.led_active_high = ath9k_led_active_high == 1;