misc: add "call" uclass op

The call op requests that the callee pass a message to the underlying HW or device, wait for a response, and then pass back the response error code and message to the callee. It is useful for drivers that represent some kind of messaging or IPC channel to a remote device. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Simon Glass <sjg@chromium.org>

misc: add "call" uclass op
The call op requests that the callee pass a message to the underlying HW or device, wait for a response, and then pass back the response error code and message to the callee. It is useful for drivers that represent some kind of messaging or IPC channel to a remote device. Signed-off-by: Stephen Warren <swarren@nvidia.com> Acked-by: Simon Glass <sjg@chromium.org>
Stephen Warren · Simon Glass
1 parent aa26776a2d
Showing 2 changed files with 46 additions and 0 deletions Side-by-side Diff
drivers/misc/misc-uclass.c
include/misc.h
@@ -45,6 +45,17 @@
 	return ops->ioctl(dev, request, buf);
 }
  
+int misc_call(struct udevice *dev, int msgid, void *tx_msg, int tx_size,
+	      void *rx_msg, int rx_size)
+{
+	const struct misc_ops *ops = device_get_ops(dev);
+
+	if (!ops->call)
+		return -ENOSYS;
+
+	return ops->call(dev, msgid, tx_msg, tx_size, rx_msg, rx_size);
+}
+
 UCLASS_DRIVER(misc) = {
 	.id		= UCLASS_MISC,
 	.name		= "misc",
@@ -38,6 +38,27 @@
 int misc_ioctl(struct udevice *dev, unsigned long request, void *buf);
  
 /*
+ * Send a message to the device and wait for a response.
+ *
+ * The caller provides the message type/ID and payload to be sent.
+ * The callee constructs any message header required, transmits it to the
+ * target, waits for a response, checks any error code in the response,
+ * strips any message header from the response, and returns the error code
+ * (or a parsed version of it) and the response message payload.
+ *
+ * @dev: the device.
+ * @msgid: the message ID/number to send.
+ * tx_msg: the request/transmit message payload.
+ * tx_size: the size of the buffer pointed at by tx_msg.
+ * rx_msg: the buffer to receive the response message payload. May be NULL if
+ *         the caller only cares about the error code.
+ * rx_size: the size of the buffer pointed at by rx_msg.
+ * @return the response message size if OK, -ve on error
+ */
+int misc_call(struct udevice *dev, int msgid, void *tx_msg, int tx_size,
+	      void *rx_msg, int rx_size);
+
+/*
  * struct misc_ops - Driver model Misc operations
  *
  * The uclass interface is implemented by all miscellaneous devices which
@@ -74,6 +95,20 @@
 	 * @return: 0 if OK, -ve on error
 	 */
 	int (*ioctl)(struct udevice *dev, unsigned long request, void *buf);
+	/*
+	 * Send a message to the device and wait for a response.
+	 *
+	 * @dev: the device
+	 * @msgid: the message ID/number to send
+	 * tx_msg: the request/transmit message payload
+	 * tx_size: the size of the buffer pointed at by tx_msg
+	 * rx_msg: the buffer to receive the response message payload. May be
+	 *         NULL if the caller only cares about the error code.
+	 * rx_size: the size of the buffer pointed at by rx_msg
+	 * @return the response message size if OK, -ve on error
+	 */
+	int (*call)(struct udevice *dev, int msgid, void *tx_msg, int tx_size,
+		    void *rx_msg, int rx_size);
 };
  
 #endif	/* _MISC_H_ */
...	...	@@ -45,6 +45,17 @@
45	45	return ops->ioctl(dev, request, buf);
46	46	}
47	47
	48	+int misc_call(struct udevice dev, int msgid, void tx_msg, int tx_size,
	49	+ void *rx_msg, int rx_size)
	50	+{
	51	+ const struct misc_ops *ops = device_get_ops(dev);
	52	+
	53	+ if (!ops->call)
	54	+ return -ENOSYS;
	55	+
	56	+ return ops->call(dev, msgid, tx_msg, tx_size, rx_msg, rx_size);
	57	+}
	58	+
48	59	UCLASS_DRIVER(misc) = {
49	60	.id = UCLASS_MISC,
50	61	.name = "misc",
...	...	@@ -38,6 +38,27 @@
38	38	int misc_ioctl(struct udevice dev, unsigned long request, void buf);
39	39
40	40	/*
	41	+ * Send a message to the device and wait for a response.
	42	+ *
	43	+ * The caller provides the message type/ID and payload to be sent.
	44	+ * The callee constructs any message header required, transmits it to the
	45	+ * target, waits for a response, checks any error code in the response,
	46	+ * strips any message header from the response, and returns the error code
	47	+ * (or a parsed version of it) and the response message payload.
	48	+ *
	49	+ * @dev: the device.
	50	+ * @msgid: the message ID/number to send.
	51	+ * tx_msg: the request/transmit message payload.
	52	+ * tx_size: the size of the buffer pointed at by tx_msg.
	53	+ * rx_msg: the buffer to receive the response message payload. May be NULL if
	54	+ * the caller only cares about the error code.
	55	+ * rx_size: the size of the buffer pointed at by rx_msg.
	56	+ * @return the response message size if OK, -ve on error
	57	+ */
	58	+int misc_call(struct udevice dev, int msgid, void tx_msg, int tx_size,
	59	+ void *rx_msg, int rx_size);
	60	+
	61	+/*
41	62	* struct misc_ops - Driver model Misc operations
42	63	*
43	64	* The uclass interface is implemented by all miscellaneous devices which
...	...	@@ -74,6 +95,20 @@
74	95	* @return: 0 if OK, -ve on error
75	96	*/
76	97	int (ioctl)(struct udevice dev, unsigned long request, void *buf);
	98	+ /*
	99	+ * Send a message to the device and wait for a response.
	100	+ *
	101	+ * @dev: the device
	102	+ * @msgid: the message ID/number to send
	103	+ * tx_msg: the request/transmit message payload
	104	+ * tx_size: the size of the buffer pointed at by tx_msg
	105	+ * rx_msg: the buffer to receive the response message payload. May be
	106	+ * NULL if the caller only cares about the error code.
	107	+ * rx_size: the size of the buffer pointed at by rx_msg
	108	+ * @return the response message size if OK, -ve on error
	109	+ */
	110	+ int (call)(struct udevice dev, int msgid, void *tx_msg, int tx_size,
	111	+ void *rx_msg, int rx_size);
77	112	};
78	113
79	114	#endif /* _MISC_H_ */