Add a power domain framework/uclass

Many SoCs allow power to be applied to or removed from portions of the SoC
(power domains). This may be used to save power. This API provides the
means to control such power management hardware.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>

1 files changed, 82 insertions, 0 deletions

diff --git a/include/power-domain-uclass.h b/include/power-domain-uclass.h
new file mode 100644
index 0000000..5878021
--- /dev/null
+++ b/include/power-domain-uclass.h
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2016, NVIDIA CORPORATION.
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#ifndef _POWER_DOMAIN_UCLASS_H
+#define _POWER_DOMAIN_UCLASS_H
+
+/* See power-domain.h for background documentation. */
+
+#include <power-domain.h>
+
+struct udevice;
+
+/**
+ * struct power_domain_ops - The functions that a power domain controller driver
+ * must implement.
+ */
+struct power_domain_ops {
+	/**
+	 * of_xlate - Translate a client's device-tree (OF) power domain
+	 * specifier.
+	 *
+	 * The power domain core calls this function as the first step in
+	 * implementing a client's power_domain_get() call.
+	 *
+	 * If this function pointer is set to NULL, the power domain core will
+	 * use a default implementation, which assumes #power-domain-cells =
+	 * <1>, and that the DT cell contains a simple integer power domain ID.
+	 *
+	 * At present, the power domain API solely supports device-tree. If
+	 * this changes, other xxx_xlate() functions may be added to support
+	 * those other mechanisms.
+	 *
+	 * @power_domain:	The power domain struct to hold the
+	 *			translation result.
+	 * @args:		The power domain specifier values from device
+	 *			tree.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*of_xlate)(struct power_domain *power_domain,
+			struct fdtdec_phandle_args *args);
+	/**
+	 * request - Request a translated power domain.
+	 *
+	 * The power domain core calls this function as the second step in
+	 * implementing a client's power_domain_get() call, following a
+	 * successful xxx_xlate() call.
+	 *
+	 * @power_domain:	The power domain to request; this has been
+	 *			filled in by a previous xxx_xlate() function
+	 *			call.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*request)(struct power_domain *power_domain);
+	/**
+	 * free - Free a previously requested power domain.
+	 *
+	 * This is the implementation of the client power_domain_free() API.
+	 *
+	 * @power_domain:	The power domain to free.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*free)(struct power_domain *power_domain);
+	/**
+	 * on - Power on a power domain.
+	 *
+	 * @power_domain:	The power domain to turn on.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*on)(struct power_domain *power_domain);
+	/**
+	 * off - Power off a power domain.
+	 *
+	 * @power_domain:	The power domain to turn off.
+	 * @return 0 if OK, or a negative error code.
+	 */
+	int (*off)(struct power_domain *power_domain);
+};
+
+#endif