ARMV7: OMAP: Add board revision detection for Overo

The latest Overo COM modules encode their revision number on
GPIOs 115, 113, and 112.  All boards to date have no pullups on these pins
and hence appear as revision 0.

This patch reads and prints the revision information.

Signed-off-by: Steve Sakoman <steve@sakoman.com>
Signed-off-by: Sandeep Paulraj <s-paulraj@ti.com>

board/overo/overo.c

@@ -60,6 +60,37 @@ int board_init(void)
 	return 0;
 }
 
+/*
+ * Routine: get_board_revision
+ * Description: Returns the board revision
+ */
+int get_board_revision(void)
+{
+	int revision;
+
+	if (!omap_request_gpio(112) &&
+	    !omap_request_gpio(113) &&
+	    !omap_request_gpio(115)) {
+
+		omap_set_gpio_direction(112, 1);
+		omap_set_gpio_direction(113, 1);
+		omap_set_gpio_direction(115, 1);
+
+		revision = omap_get_gpio_datain(115) << 2 |
+			   omap_get_gpio_datain(113) << 1 |
+			   omap_get_gpio_datain(112);
+
+		omap_free_gpio(112);
+		omap_free_gpio(113);
+		omap_free_gpio(115);
+	} else {
+		printf("Error: unable to acquire board revision GPIOs\n");
+		revision = -1;
+	}
+
+	return revision;
+}
+
 /*
  * Routine: misc_init_r
  * Description: Configure board specific parts
@@ -73,6 +104,7 @@ int misc_init_r(void)
 	setup_net_chip();
 #endif
 
+	printf("Board revision: %d\n", get_board_revision());
 	dieid_num_r();
 
 	return 0;

board/overo/overo.h

@@ -189,11 +189,11 @@ const omap3_sysinfo sysinfo = {
 	MUX_VAL(CP(CAM_XCLKB),		(IDIS | PTD | DIS | M0)) /*CAM_XCLKB*/\
 	MUX_VAL(CP(CAM_WEN),		(IEN  | PTD | DIS | M0)) /*CAM_WEN*/\
 	MUX_VAL(CP(CAM_STROBE),		(IDIS | PTD | DIS | M0)) /*CAM_STROBE*/\
-	MUX_VAL(CP(CSI2_DX0),		(IEN  | PTD | DIS | M0)) /*CSI2_DX0*/\
-	MUX_VAL(CP(CSI2_DY0),		(IEN  | PTD | DIS | M0)) /*CSI2_DY0*/\
+	MUX_VAL(CP(CSI2_DX0),		(IEN  | PTD | EN  | M4)) /*GPIO_112*/\
+	MUX_VAL(CP(CSI2_DY0),		(IEN  | PTD | EN  | M4)) /*GPIO_113*/\
 	MUX_VAL(CP(CSI2_DX1),		(IEN  | PTD | EN  | M4)) /*GPIO_114*/\
 								 /* - PEN_DOWN*/\
-	MUX_VAL(CP(CSI2_DY1),		(IEN  | PTU | EN  | M4)) /*GPIO_115*/\
+	MUX_VAL(CP(CSI2_DY1),		(IEN  | PTD | EN  | M4)) /*GPIO_115*/\
  /*Audio Interface */\
 	MUX_VAL(CP(MCBSP2_FSX),		(IEN  | PTD | DIS | M0)) /*McBSP2_FSX*/\
 	MUX_VAL(CP(MCBSP2_CLKX),	(IEN  | PTD | DIS | M0)) /*McBSP2_CLKX*/\