Implement GPIO hogging.

ok patrick@

1 files changed, 48 insertions, 2 deletions

diff --git a/sys/dev/ofw/ofw_gpio.c b/sys/dev/ofw/ofw_gpio.c
index 5f814ac7322..f8f818e8fb1 100644
--- a/sys/dev/ofw/ofw_gpio.c
+++ b/sys/dev/ofw/ofw_gpio.c
@@ -1,6 +1,6 @@
-/*	$OpenBSD: ofw_gpio.c,v 1.2 2016/07/27 21:13:49 kettenis Exp $	*/
+/*	$OpenBSD: ofw_gpio.c,v 1.3 2019/08/26 09:22:27 kettenis Exp $	*/
 /*
- * Copyright (c) 2016 Mark Kettenis
+ * Copyright (c) 2016, 2019 Mark Kettenis
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -17,6 +17,7 @@
 
 #include <sys/types.h>
 #include <sys/systm.h>
+#include <sys/malloc.h>
 
 #include <dev/ofw/openfirm.h>
 #include <dev/ofw/ofw_gpio.h>
@@ -27,12 +28,57 @@ LIST_HEAD(, gpio_controller) gpio_controllers =
 void
 gpio_controller_register(struct gpio_controller *gc)
 {
+	int child;
+
 	gc->gc_cells = OF_getpropint(gc->gc_node, "#gpio-cells", 2);
 	gc->gc_phandle = OF_getpropint(gc->gc_node, "phandle", 0);
 	if (gc->gc_phandle == 0)
 		return;
 
 	LIST_INSERT_HEAD(&gpio_controllers, gc, gc_list);
+
+	/* Process GPIO hogs. */
+	for (child = OF_child(gc->gc_node); child; child = OF_peer(child)) {
+		uint32_t *gpios;
+		uint32_t *gpio;
+		int len, config, active;
+
+		if (OF_getproplen(child, "gpio-hog") != 0)
+			continue;
+
+		len = OF_getproplen(child, "gpios");
+		if (len <= 0)
+			continue;
+
+		/*
+		 * These need to be processed in the order prescribed
+		 * by the device tree binding.  First match wins.
+		 */
+		if (OF_getproplen(child, "input") == 0) {
+			config = GPIO_CONFIG_INPUT;
+			active = 0;
+		} else if (OF_getproplen(child, "output-low") == 0) {
+			config = GPIO_CONFIG_OUTPUT;
+			active = 0;
+		} else if (OF_getproplen(child, "output-high") == 0) {
+			config = GPIO_CONFIG_OUTPUT;
+			active = 1;
+		} else
+			continue;
+
+		gpios = malloc(len, M_TEMP, M_WAITOK);
+		OF_getpropintarray(child, "gpios", gpios, len);
+
+		gpio = gpios;
+		while (gpio && gpio < gpios + (len / sizeof(uint32_t))) {
+			gc->gc_config_pin(gc->gc_cookie, gpio, config);
+			if (config & GPIO_CONFIG_OUTPUT)
+				gc->gc_set_pin(gc->gc_cookie, gpio, active);
+			gpio += gc->gc_cells;
+		}
+
+		free(gpios, M_TEMP, len);
+	}
 }
 
 void