Merge tag 'tags/ib-chrome-psy-5.3' into psy-next

Immutable branch between Power Supply and Chrome Platform due for the
v5.3 merge window
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/platform/chrome/wilco_ec/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
-wilco_ec-objs				:= core.o mailbox.o
+wilco_ec-objs				:= core.o mailbox.o properties.o
 obj-$(CONFIG_WILCO_EC)			+= wilco_ec.o
 wilco_ec_debugfs-objs			:= debugfs.o
 obj-$(CONFIG_WILCO_EC_DEBUGFS)		+= wilco_ec_debugfs.o

drivers/platform/chrome/wilco_ec/properties.c

+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Google LLC
+ */
+
+#include <linux/platform_data/wilco-ec.h>
+#include <linux/string.h>
+#include <linux/unaligned/le_memmove.h>
+
+/* Operation code; what the EC should do with the property */
+enum ec_property_op {
+	EC_OP_GET = 0,
+	EC_OP_SET = 1,
+};
+
+struct ec_property_request {
+	u8 op; /* One of enum ec_property_op */
+	u8 property_id[4]; /* The 32 bit PID is stored Little Endian */
+	u8 length;
+	u8 data[WILCO_EC_PROPERTY_MAX_SIZE];
+} __packed;
+
+struct ec_property_response {
+	u8 reserved[2];
+	u8 op; /* One of enum ec_property_op */
+	u8 property_id[4]; /* The 32 bit PID is stored Little Endian */
+	u8 length;
+	u8 data[WILCO_EC_PROPERTY_MAX_SIZE];
+} __packed;
+
+static int send_property_msg(struct wilco_ec_device *ec,
+			     struct ec_property_request *rq,
+			     struct ec_property_response *rs)
+{
+	struct wilco_ec_message ec_msg;
+	int ret;
+
+	memset(&ec_msg, 0, sizeof(ec_msg));
+	ec_msg.type = WILCO_EC_MSG_PROPERTY;
+	ec_msg.request_data = rq;
+	ec_msg.request_size = sizeof(*rq);
+	ec_msg.response_data = rs;
+	ec_msg.response_size = sizeof(*rs);
+
+	ret = wilco_ec_mailbox(ec, &ec_msg);
+	if (ret < 0)
+		return ret;
+	if (rs->op != rq->op)
+		return -EBADMSG;
+	if (memcmp(rq->property_id, rs->property_id, sizeof(rs->property_id)))
+		return -EBADMSG;
+
+	return 0;
+}
+
+int wilco_ec_get_property(struct wilco_ec_device *ec,
+			  struct wilco_ec_property_msg *prop_msg)
+{
+	struct ec_property_request rq;
+	struct ec_property_response rs;
+	int ret;
+
+	memset(&rq, 0, sizeof(rq));
+	rq.op = EC_OP_GET;
+	put_unaligned_le32(prop_msg->property_id, rq.property_id);
+
+	ret = send_property_msg(ec, &rq, &rs);
+	if (ret < 0)
+		return ret;
+
+	prop_msg->length = rs.length;
+	memcpy(prop_msg->data, rs.data, rs.length);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(wilco_ec_get_property);
+
+int wilco_ec_set_property(struct wilco_ec_device *ec,
+			  struct wilco_ec_property_msg *prop_msg)
+{
+	struct ec_property_request rq;
+	struct ec_property_response rs;
+	int ret;
+
+	memset(&rq, 0, sizeof(rq));
+	rq.op = EC_OP_SET;
+	put_unaligned_le32(prop_msg->property_id, rq.property_id);
+	rq.length = prop_msg->length;
+	memcpy(rq.data, prop_msg->data, prop_msg->length);
+
+	ret = send_property_msg(ec, &rq, &rs);
+	if (ret < 0)
+		return ret;
+	if (rs.length != prop_msg->length)
+		return -EBADMSG;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(wilco_ec_set_property);
+
+int wilco_ec_get_byte_property(struct wilco_ec_device *ec, u32 property_id,
+			       u8 *val)
+{
+	struct wilco_ec_property_msg msg;
+	int ret;
+
+	msg.property_id = property_id;
+
+	ret = wilco_ec_get_property(ec, &msg);
+	if (ret < 0)
+		return ret;
+	if (msg.length != 1)
+		return -EBADMSG;
+
+	*val = msg.data[0];
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(wilco_ec_get_byte_property);
+
+int wilco_ec_set_byte_property(struct wilco_ec_device *ec, u32 property_id,
+			       u8 val)
+{
+	struct wilco_ec_property_msg msg;
+
+	msg.property_id = property_id;
+	msg.data[0] = val;
+	msg.length = 1;
+
+	return wilco_ec_set_property(ec, &msg);
+}
+EXPORT_SYMBOL_GPL(wilco_ec_set_byte_property);

include/linux/platform_data/wilco-ec.h

@@ -123,4 +123,75 @@ struct wilco_ec_message {
  */
 int wilco_ec_mailbox(struct wilco_ec_device *ec, struct wilco_ec_message *msg);
 
+/*
+ * A Property is typically a data item that is stored to NVRAM
+ * by the EC. Each of these data items has an index associated
+ * with it, known as the Property ID (PID). Properties may have
+ * variable lengths, up to a max of WILCO_EC_PROPERTY_MAX_SIZE
+ * bytes. Properties can be simple integers, or they may be more
+ * complex binary data.
+ */
+
+#define WILCO_EC_PROPERTY_MAX_SIZE	4
+
+/**
+ * struct ec_property_set_msg - Message to get or set a property.
+ * @property_id: Which property to get or set.
+ * @length: Number of bytes of |data| that are used.
+ * @data: Actual property data.
+ */
+struct wilco_ec_property_msg {
+	u32 property_id;
+	int length;
+	u8 data[WILCO_EC_PROPERTY_MAX_SIZE];
+};
+
+/**
+ * wilco_ec_get_property() - Retrieve a property from the EC.
+ * @ec: Embedded Controller device.
+ * @prop_msg: Message for request and response.
+ *
+ * The property_id field of |prop_msg| should be filled before calling this
+ * function. The result will be stored in the data and length fields.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int wilco_ec_get_property(struct wilco_ec_device *ec,
+			  struct wilco_ec_property_msg *prop_msg);
+
+/**
+ * wilco_ec_set_property() - Store a property on the EC.
+ * @ec: Embedded Controller device.
+ * @prop_msg: Message for request and response.
+ *
+ * The property_id, length, and data fields of |prop_msg| should be
+ * filled before calling this function.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int wilco_ec_set_property(struct wilco_ec_device *ec,
+			  struct wilco_ec_property_msg *prop_msg);
+
+/**
+ * wilco_ec_get_byte_property() - Retrieve a byte-size property from the EC.
+ * @ec: Embedded Controller device.
+ * @property_id: Which property to retrieve.
+ * @val: The result value, will be filled by this function.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int wilco_ec_get_byte_property(struct wilco_ec_device *ec, u32 property_id,
+			       u8 *val);
+
+/**
+ * wilco_ec_get_byte_property() - Store a byte-size property on the EC.
+ * @ec: Embedded Controller device.
+ * @property_id: Which property to store.
+ * @val: Value to store.
+ *
+ * Return: 0 on success, negative error code on failure.
+ */
+int wilco_ec_set_byte_property(struct wilco_ec_device *ec, u32 property_id,
+			       u8 val);
+
 #endif /* WILCO_EC_H */