Commit 88d9b2b3 authored by Alexandre Peixoto Ferreira's avatar Alexandre Peixoto Ferreira Committed by Greg Kroah-Hartman

USB: usbtmc: TMC request code segregated from usbtmc_read

These patches implement a modification of the USBTMC
protocol to allow operation with Rigol equipment. The TMC request portion of
the code in function usbtmc_read is segregated to a function
send_request_dev_dep_msg_in as implemented by tommie in
https://github.com/tommie/linux/blob/usbtmc-rigol/drivers/usb/class/usbtmc.c
allowing the reuse later.
Signed-off-by: default avatarAlexandre Peixoto Ferreira <alexandref75@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8402db5d
......@@ -375,6 +375,59 @@ static int usbtmc_ioctl_abort_bulk_out(struct usbtmc_device_data *data)
return rv;
}
/*
* Sends a REQUEST_DEV_DEP_MSG_IN message on the Bulk-IN endpoint.
* @transfer_size: number of bytes to request from the device.
*
* See the USBTMC specification, Table 4.
*
* Also updates bTag_last_write.
*/
static int send_request_dev_dep_msg_in(struct usbtmc_device_data *data, size_t transfer_size)
{
int retval;
u8 buffer[USBTMC_HEADER_SIZE];
int actual;
/* Setup IO buffer for REQUEST_DEV_DEP_MSG_IN message
* Refer to class specs for details
*/
buffer[0] = 2;
buffer[1] = data->bTag;
buffer[2] = ~(data->bTag);
buffer[3] = 0; /* Reserved */
buffer[4] = (transfer_size) & 255;
buffer[5] = ((transfer_size) >> 8) & 255;
buffer[6] = ((transfer_size) >> 16) & 255;
buffer[7] = ((transfer_size) >> 24) & 255;
buffer[8] = data->TermCharEnabled * 2;
/* Use term character? */
buffer[9] = data->TermChar;
buffer[10] = 0; /* Reserved */
buffer[11] = 0; /* Reserved */
/* Send bulk URB */
retval = usb_bulk_msg(data->usb_dev,
usb_sndbulkpipe(data->usb_dev,
data->bulk_out),
buffer, USBTMC_HEADER_SIZE, &actual, USBTMC_TIMEOUT);
/* Store bTag (in case we need to abort) */
data->bTag_last_write = data->bTag;
/* Increment bTag -- and increment again if zero */
data->bTag++;
if (!data->bTag)
(data->bTag)++;
if (retval < 0) {
dev_err(&data->intf->dev, "usb_bulk_msg in send_request_dev_dep_msg_in() returned %d\n", retval);
return retval;
}
return 0;
}
static ssize_t usbtmc_read(struct file *filp, char __user *buf,
size_t count, loff_t *f_pos)
{
......@@ -411,37 +464,7 @@ static ssize_t usbtmc_read(struct file *filp, char __user *buf,
else
this_part = remaining;
/* Setup IO buffer for DEV_DEP_MSG_IN message
* Refer to class specs for details
*/
buffer[0] = 2;
buffer[1] = data->bTag;
buffer[2] = ~(data->bTag);
buffer[3] = 0; /* Reserved */
buffer[4] = (this_part) & 255;
buffer[5] = ((this_part) >> 8) & 255;
buffer[6] = ((this_part) >> 16) & 255;
buffer[7] = ((this_part) >> 24) & 255;
buffer[8] = data->TermCharEnabled * 2;
/* Use term character? */
buffer[9] = data->TermChar;
buffer[10] = 0; /* Reserved */
buffer[11] = 0; /* Reserved */
/* Send bulk URB */
retval = usb_bulk_msg(data->usb_dev,
usb_sndbulkpipe(data->usb_dev,
data->bulk_out),
buffer, 12, &actual, USBTMC_TIMEOUT);
/* Store bTag (in case we need to abort) */
data->bTag_last_write = data->bTag;
/* Increment bTag -- and increment again if zero */
data->bTag++;
if (!data->bTag)
(data->bTag)++;
retval = send_request_dev_dep_msg_in(data, this_part);
if (retval < 0) {
dev_err(dev, "usb_bulk_msg returned %d\n", retval);
if (data->auto_abort)
......
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