pce-322a: unbreak send_command() return code

Data was sent to the serial port, and the non-zero positive write length
was mistaken as an error, since it did not match the SR_OK code's value.
This snuck in with commit 379e95c587 in 2017-08.

Rephrase the check for successful serial writes in the pce-322a driver.
Pass on error codes from the serial layer in verbatim form. Check for
the exact expected write length and derive SR_ERR_IO upon mismatch. Do
return SR_OK upon success.

Reported-By: Michael Ströder <michael@stroeder.com>
Tested-By: Michael Ströder <michael@stroeder.com>
This commit is contained in:
Gerhard Sittig 2020-10-02 11:18:57 +02:00
parent 5a0303474c
commit a4be2b327b
1 changed files with 16 additions and 2 deletions

View File

@ -26,6 +26,7 @@ static int send_command(const struct sr_dev_inst *sdi, uint16_t command)
{
struct sr_serial_dev_inst *serial;
uint8_t buffer[2];
int ret;
buffer[0] = command >> 8;
buffer[1] = command;
@ -33,13 +34,20 @@ static int send_command(const struct sr_dev_inst *sdi, uint16_t command)
if (!(serial = sdi->conn))
return SR_ERR;
return serial_write_blocking(serial, (const void *)buffer, 2, 0);
ret = serial_write_blocking(serial, buffer, sizeof(buffer), 0);
if (ret < 0)
return ret;
if ((size_t)ret != sizeof(buffer))
return SR_ERR_IO;
return SR_OK;
}
static int send_long_command(const struct sr_dev_inst *sdi, uint32_t command)
{
struct sr_serial_dev_inst *serial;
uint8_t buffer[4];
int ret;
buffer[0] = command >> 24;
buffer[1] = command >> 16;
@ -49,7 +57,13 @@ static int send_long_command(const struct sr_dev_inst *sdi, uint32_t command)
if (!(serial = sdi->conn))
return SR_ERR;
return serial_write_blocking(serial, (const void *)buffer, 4, 0);
ret = serial_write_blocking(serial, buffer, sizeof(buffer), 0);
if (ret < 0)
return ret;
if ((size_t)ret != sizeof(buffer))
return SR_ERR_IO;
return SR_OK;
}
static void send_data(const struct sr_dev_inst *sdi, float sample)