gru: set correct gpio for SD card detect

The only outlier at this time is Kevin rev 0, treat it specially, the
rest of the targets use the same GPIO.

BRANCH=none
BUG=none
TEST=gru still boots off SD card just fine

Change-Id: Ic603093a990d27166b16175db3303f155b4775aa
Signed-off-by: Martin Roth <martinroth@google.com>
Original-Commit-Id: 5788c5add1d1f803e7b22fb53215b6003ac04d03
Original-Change-Id: Ic5183f08dd1119f9588f243bd9e9c080d84687f9
Original-Signed-off-by: Vadim Bendebury <vbendeb@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/344151
Original-Reviewed-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: https://review.coreboot.org/14851
Tested-by: build bot (Jenkins)
Reviewed-by: Vadim Bendebury <vbendeb@chromium.org>
diff --git a/src/mainboard/google/gru/mainboard.c b/src/mainboard/google/gru/mainboard.c
index e91f289..b7a197e 100644
--- a/src/mainboard/google/gru/mainboard.c
+++ b/src/mainboard/google/gru/mainboard.c
@@ -24,19 +24,13 @@
 {
 	gpio_output(GPIO(4, D, 5), 1);  /* SDMMC_PWR_EN */
 	gpio_output(GPIO(2, A, 2), 1);  /* SDMMC_SDIO_PWR_EN */
-	/*
-	 * SDMMC_DET_L is different on different board revisions.
-	 * Ideally this and other deviations should come from a table
-	 * which could be looked up by board revision.
-	 */
-	switch (board_id()) {
-	case 0:  /* This is for Kevin proto 1. */
+
+	/* SDMMC_DET_L is different on Kevin board revision 0. */
+	if (IS_ENABLED(CONFIG_BOARD_GOOGLE_KEVIN) && (board_id() == 0))
 		gpio_input(GPIO(4, D, 2));
-		break;
-	default:
+	else
 		gpio_input(GPIO(4, D, 0));
-		break;
-	}
+
 	gpio_output(GPIO(2, D, 4), 0);  /* Keep the max voltage */
 
 	write32(&rk3399_grf->iomux_sdmmc, IOMUX_SDMMC);