From 74346841e6f5df5f7b83d5904435d273c507dba6 Mon Sep 17 00:00:00 2001 From: Ricardo Ribalda Delgado Date: Thu, 13 Aug 2015 16:09:28 +0200 Subject: [PATCH] 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 Tested-by: Edward Kigwana Signed-off-by: Ricardo Ribalda Delgado Signed-off-by: Mark Brown Cc: stable@vger.kernel.org --- drivers/spi/spi-xilinx.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c index 7abf679..a339c1e 100644 --- a/drivers/spi/spi-xilinx.c +++ b/drivers/spi/spi-xilinx.c @@ -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) { -- 2.7.4