diff options
| -rw-r--r-- | drivers/usb/core/message.c | 133 | ||||
| -rw-r--r-- | include/linux/usb.h | 6 |
2 files changed, 139 insertions, 0 deletions
diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c index ae1de9cc4b09..1dc53b12a26a 100644 --- a/drivers/usb/core/message.c +++ b/drivers/usb/core/message.c @@ -163,6 +163,139 @@ int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request, EXPORT_SYMBOL_GPL(usb_control_msg); /** + * usb_control_msg_send - Builds a control "send" message, sends it off and waits for completion + * @dev: pointer to the usb device to send the message to + * @endpoint: endpoint to send the message to + * @request: USB message request value + * @requesttype: USB message request type value + * @value: USB message value + * @index: USB message index value + * @driver_data: pointer to the data to send + * @size: length in bytes of the data to send + * @timeout: time in msecs to wait for the message to complete before timing + * out (if 0 the wait is forever) + * + * Context: !in_interrupt () + * + * This function sends a control message to a specified endpoint that is not + * expected to fill in a response (i.e. a "send message") and waits for the + * message to complete, or timeout. + * + * Do not use this function from within an interrupt context. If you need + * an asynchronous message, or need to send a message from within interrupt + * context, use usb_submit_urb(). If a thread in your driver uses this call, + * make sure your disconnect() method can wait for it to complete. Since you + * don't have a handle on the URB used, you can't cancel the request. + * + * The data pointer can be made to a reference on the stack, or anywhere else, + * as it will not be modified at all. This does not have the restriction that + * usb_control_msg() has where the data pointer must be to dynamically allocated + * memory (i.e. memory that can be successfully DMAed to a device). + * + * Return: If successful, 0 is returned, Otherwise, a negative error number. + */ +int usb_control_msg_send(struct usb_device *dev, __u8 endpoint, __u8 request, + __u8 requesttype, __u16 value, __u16 index, + const void *driver_data, __u16 size, int timeout) +{ + unsigned int pipe = usb_sndctrlpipe(dev, endpoint); + int ret; + u8 *data = NULL; + + if (usb_pipe_type_check(dev, pipe)) + return -EINVAL; + + if (size) { + data = kmemdup(driver_data, size, GFP_KERNEL); + if (!data) + return -ENOMEM; + } + + ret = usb_control_msg(dev, pipe, request, requesttype, value, index, + data, size, timeout); + kfree(data); + + if (ret < 0) + return ret; + if (ret == size) + return 0; + return -EINVAL; +} +EXPORT_SYMBOL_GPL(usb_control_msg_send); + +/** + * usb_control_msg_recv - Builds a control "receive" message, sends it off and waits for completion + * @dev: pointer to the usb device to send the message to + * @endpoint: endpoint to send the message to + * @request: USB message request value + * @requesttype: USB message request type value + * @value: USB message value + * @index: USB message index value + * @driver_data: pointer to the data to be filled in by the message + * @size: length in bytes of the data to be received + * @timeout: time in msecs to wait for the message to complete before timing + * out (if 0 the wait is forever) + * + * Context: !in_interrupt () + * + * This function sends a control message to a specified endpoint that is + * expected to fill in a response (i.e. a "receive message") and waits for the + * message to complete, or timeout. + * + * Do not use this function from within an interrupt context. If you need + * an asynchronous message, or need to send a message from within interrupt + * context, use usb_submit_urb(). If a thread in your driver uses this call, + * make sure your disconnect() method can wait for it to complete. Since you + * don't have a handle on the URB used, you can't cancel the request. + * + * The data pointer can be made to a reference on the stack, or anywhere else + * that can be successfully written to. This function does not have the + * restriction that usb_control_msg() has where the data pointer must be to + * dynamically allocated memory (i.e. memory that can be successfully DMAed to a + * device). + * + * The "whole" message must be properly received from the device in order for + * this function to be successful. If a device returns less than the expected + * amount of data, then the function will fail. Do not use this for messages + * where a variable amount of data might be returned. + * + * Return: If successful, 0 is returned, Otherwise, a negative error number. + */ +int usb_control_msg_recv(struct usb_device *dev, __u8 endpoint, __u8 request, + __u8 requesttype, __u16 value, __u16 index, + void *driver_data, __u16 size, int timeout) +{ + unsigned int pipe = usb_rcvctrlpipe(dev, endpoint); + int ret; + u8 *data; + + if (!size || !driver_data || usb_pipe_type_check(dev, pipe)) + return -EINVAL; + + data = kmalloc(size, GFP_KERNEL); + if (!data) + return -ENOMEM; + + ret = usb_control_msg(dev, pipe, request, requesttype, value, index, + data, size, timeout); + + if (ret < 0) + goto exit; + + if (ret == size) { + memcpy(driver_data, data, size); + ret = 0; + } else { + ret = -EINVAL; + } + +exit: + kfree(data); + return ret; +} +EXPORT_SYMBOL_GPL(usb_control_msg_recv); + +/** * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion * @usb_dev: pointer to the usb device to send the message to * @pipe: endpoint "pipe" to send the message to diff --git a/include/linux/usb.h b/include/linux/usb.h index 0b3963d7ec38..a5460f08126e 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -1802,6 +1802,12 @@ extern int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe, int timeout); /* wrappers around usb_control_msg() for the most common standard requests */ +int usb_control_msg_send(struct usb_device *dev, __u8 endpoint, __u8 request, + __u8 requesttype, __u16 value, __u16 index, + const void *data, __u16 size, int timeout); +int usb_control_msg_recv(struct usb_device *dev, __u8 endpoint, __u8 request, + __u8 requesttype, __u16 value, __u16 index, + void *data, __u16 size, int timeout); extern int usb_get_descriptor(struct usb_device *dev, unsigned char desctype, unsigned char descindex, void *buf, int size); extern int usb_get_status(struct usb_device *dev, |