ssb: pci: implement mdio reading

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/ssb/driver_pcicore.c

@@ -467,6 +467,49 @@ static void ssb_pcie_mdio_set_phy(struct ssb_pcicore *pc, u8 phy)
 	}
 }
 
+#if 0
+//done but not used yet
+static u16 ssb_pcie_mdio_read(struct ssb_pcicore *pc, u8 device, u8 address)
+{
+	const u16 mdio_control = 0x128;
+	const u16 mdio_data = 0x12C;
+	int max_retries = 10;
+	u16 ret = 0;
+	u32 v;
+	int i;
+
+	v = 0x80; /* Enable Preamble Sequence */
+	v |= 0x2; /* MDIO Clock Divisor */
+	pcicore_write32(pc, mdio_control, v);
+
+	if (pc->dev->id.revision >= 10) {
+		max_retries = 200;
+		ssb_pcie_mdio_set_phy(pc, device);
+	}
+
+	v = (1 << 30); /* Start of Transaction */
+	v |= (1 << 29); /* Read Transaction */
+	v |= (1 << 17); /* Turnaround */
+	if (pc->dev->id.revision < 10)
+		v |= (u32)device << 22;
+	v |= (u32)address << 18;
+	pcicore_write32(pc, mdio_data, v);
+	/* Wait for the device to complete the transaction */
+	udelay(10);
+	for (i = 0; i < 200; i++) {
+		v = pcicore_read32(pc, mdio_control);
+		if (v & 0x100 /* Trans complete */) {
+			udelay(10);
+			ret = pcicore_read32(pc, mdio_data);
+			break;
+		}
+		msleep(1);
+	}
+	pcicore_write32(pc, mdio_control, 0);
+	return ret;
+}
+#endif
+
 static void ssb_pcie_mdio_write(struct ssb_pcicore *pc, u8 device,
 				u8 address, u16 data)
 {