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mirror of https://review.coreboot.org/flashrom.git synced 2025-04-26 22:52:34 +02:00

Prevent submission of empty read requests in linux_spi

The submission of zero-sized read requests in a write-only transaction
fails at least for omap2_mcspi drivers and is pointless in general.

This patch does not address the implementation of zero-sized writes (which
would need to skip the write command), as there are no flash transactions
not starting with a command.

Corresponding to flashrom svn r1513.

Signed-off-by: Michael Karcher <flashrom@mkarcher.dialup.fu-berlin.de>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
This commit is contained in:
Michael Karcher 2012-03-06 22:17:06 +00:00
parent 2c3e9d5f57
commit 8371d7238a

View File

@ -130,6 +130,7 @@ static int linux_spi_send_command(struct flashctx *flash, unsigned int writecnt,
const unsigned char *txbuf,
unsigned char *rxbuf)
{
int iocontrol_code;
struct spi_ioc_transfer msg[2] = {
{
.tx_buf = (uint64_t)(ptrdiff_t)txbuf,
@ -143,8 +144,19 @@ static int linux_spi_send_command(struct flashctx *flash, unsigned int writecnt,
if (fd == -1)
return -1;
/* The implementation currently does not support requests that
don't start with sending a command. */
if (writecnt == 0)
return SPI_INVALID_LENGTH;
if (ioctl(fd, SPI_IOC_MESSAGE(2), msg) == -1) {
/* Just submit the first (write) request in case there is nothing
to read. Otherwise submit both requests. */
if (readcnt == 0)
iocontrol_code = SPI_IOC_MESSAGE(1);
else
iocontrol_code = SPI_IOC_MESSAGE(2);
if (ioctl(fd, iocontrol_code, msg) == -1) {
msg_cerr("%s: ioctl: %s\n", __func__, strerror(errno));
return -1;
}