spi/spi-xilinx: Fix spurious IRQ ACK on irq mode

The ACK of an inexistent IRQ can trigger an spurious IRQ that breaks the
txrx logic. This has been observed on axi_quad_spi:3.2 core.

This patch only ACKs IRQs that have not been Acknowledge jet.

Reported-by: Edward Kigwana <ekigwana@scires.com>
Tested-by: Edward Kigwana <ekigwana@scires.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
This commit is contained in:
Ricardo Ribalda Delgado 2015-08-13 16:09:28 +02:00 committed by Mark Brown
parent 16ea9b8ac4
commit 74346841e6

View file

@ -249,19 +249,23 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
xspi->tx_ptr = t->tx_buf;
xspi->rx_ptr = t->rx_buf;
remaining_words = t->len / xspi->bytes_per_word;
reinit_completion(&xspi->done);
if (xspi->irq >= 0 && remaining_words > xspi->buffer_size) {
u32 isr;
use_irq = true;
xspi->write_fn(XSPI_INTR_TX_EMPTY,
xspi->regs + XIPIF_V123B_IISR_OFFSET);
/* Enable the global IPIF interrupt */
xspi->write_fn(XIPIF_V123B_GINTR_ENABLE,
xspi->regs + XIPIF_V123B_DGIER_OFFSET);
/* Inhibit irq to avoid spurious irqs on tx_empty*/
cr = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET);
xspi->write_fn(cr | XSPI_CR_TRANS_INHIBIT,
xspi->regs + XSPI_CR_OFFSET);
/* ACK old irqs (if any) */
isr = xspi->read_fn(xspi->regs + XIPIF_V123B_IISR_OFFSET);
if (isr)
xspi->write_fn(isr,
xspi->regs + XIPIF_V123B_IISR_OFFSET);
/* Enable the global IPIF interrupt */
xspi->write_fn(XIPIF_V123B_GINTR_ENABLE,
xspi->regs + XIPIF_V123B_DGIER_OFFSET);
reinit_completion(&xspi->done);
}
while (remaining_words) {