[PATCH v1 5/8] ARM: boards: skov-imx6: rework switch detection

[Oleksij Rempel <o.rempel@pengutronix.de>]

The KSZ8873 switch supports two ways of communication over MDIO bus:
1. Standard MDIO opcodes to talk with the switch PHYs only.
2. Not standard MDIO opcodes to talk with complete switch management and
   PHYs.

Previous switch detection board code was using option 1. over FEC. Now,
with the switch driver we are using option 2. with GPIO bitbang MDIO
bus, since FEC do not support special opcodes.

To avoid duplicating switch driver functionality, we will let do switch
detection and validation to the switch driver and the board code should
only test if switch driver was probed.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 arch/arm/boards/skov-imx6/board.c | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/arch/arm/boards/skov-imx6/board.c b/arch/arm/boards/skov-imx6/board.c
index 140689c87b..3c51b76735 100644
--- a/arch/arm/boards/skov-imx6/board.c
+++ b/arch/arm/boards/skov-imx6/board.c
@@ -133,9 +133,6 @@ copy_mac_from_eth0:
 	return eth_of_fixup_node_from_eth_device(root, node_path, ethname);
 }
 
-#define SKOV_GPIO_MDIO_BUS	0
-#define SKOV_LAN1_PHY_ADDR	1
-
 #define MAX_V_GPIO 8
 
 struct board_description {
@@ -547,29 +544,25 @@ static void skov_init_board(const struct board_description *variant)
 
 static int skov_switch_test(void)
 {
-	struct phy_device *phydev;
+	struct device_d *sw_dev;
 	struct device_d *eth0;
-	struct mii_bus *mii;
 	int ret;
 
 	if (skov_board_no < 0)
 		return 0;
 
-	/* On this boards, we have only one MDIO bus. So, it is enough to take
-	 * the first one.
-	 */
-	mii = mdiobus_get_bus(SKOV_GPIO_MDIO_BUS);
-	/* We can't read the switch ID, but we get get ID of the first PHY,
-	 * which is enough to test if the switch is attached.
+	/* Driver should be able to detect if device do actually
+	 * exist. So, we need only to detect if driver is actually
+	 * probed.
 	 */
-	phydev = get_phy_device(mii, SKOV_LAN1_PHY_ADDR);
-	if (IS_ERR(phydev))
-		goto no_switch;
-
-	if (phydev->phy_id != PHY_ID_KSZ886X)
+	sw_dev = of_find_device_by_node_path("/mdio/switch@0");
+	if (!sw_dev) {
+		pr_err("switch@0 device was not created!\n");
 		goto no_switch;
+	}
 
-	return 0;
+	if (dev_is_probed(sw_dev))
+		return 0;
 
 no_switch:
 	skov_have_switch = false;
-- 
2.30.2