From: Stephen Warren swarren@nvidia.com
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 --- v3: New patch. --- drivers/misc/misc-uclass.c | 11 +++++++++++ include/misc.h | 35 +++++++++++++++++++++++++++++++++++ 2 files changed, 46 insertions(+)
diff --git a/drivers/misc/misc-uclass.c b/drivers/misc/misc-uclass.c index 13a6ea508b14..d9eea3dac5c0 100644 --- a/drivers/misc/misc-uclass.c +++ b/drivers/misc/misc-uclass.c @@ -45,6 +45,17 @@ int misc_ioctl(struct udevice *dev, unsigned long request, void *buf) 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", diff --git a/include/misc.h b/include/misc.h index 2b788143b54c..ba417380416a 100644 --- a/include/misc.h +++ b/include/misc.h @@ -38,6 +38,27 @@ int misc_write(struct udevice *dev, int offset, void *buf, int size); 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 0 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 @@ struct misc_ops { * @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 0 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_ */