cros_ec: Handle the single duplex requirement in cros_ec
With several chips using the SPI protocol it seems better to put the single
duplex functionality in the EC rather than the SPI driver.
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/misc/cros_ec_spi.c b/drivers/misc/cros_ec_spi.c
index ac2ee86..0686925 100644
--- a/drivers/misc/cros_ec_spi.c
+++ b/drivers/misc/cros_ec_spi.c
@@ -25,6 +25,8 @@
{
struct cros_ec_dev *dev = dev_get_uclass_priv(udev);
struct spi_slave *slave = dev_get_parentdata(dev->dev);
+ ulong start;
+ uint8_t byte;
int rv;
/* Do the transfer */
@@ -33,10 +35,25 @@
return -1;
}
- rv = spi_xfer(slave, max(out_bytes, in_bytes) * 8,
- dev->dout, dev->din,
- SPI_XFER_BEGIN | SPI_XFER_END);
+ rv = spi_xfer(slave, out_bytes * 8, dev->dout, NULL, SPI_XFER_BEGIN);
+ if (rv)
+ goto done;
+ start = get_timer(0);
+ while (1) {
+ rv = spi_xfer(slave, 8, NULL, &byte, 0);
+ if (byte == SPI_PREAMBLE_END_BYTE)
+ break;
+ if (rv)
+ goto done;
+ if (get_timer(start) > 100) {
+ rv = -ETIMEDOUT;
+ goto done;
+ }
+ }
+ rv = spi_xfer(slave, in_bytes * 8, NULL, dev->din, 0);
+done:
+ spi_xfer(slave, 0, NULL, NULL, SPI_XFER_END);
spi_release_bus(slave);
if (rv) {