Merge tag 'spi-v3.17-rc3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi bugfixes from Mark Brown:
 "A smattering of bug fixes for the SPI subsystem, all in driver code
  which has seen active work recently and none of them with any great
  global impact.

  There's also a new ACPI ID for the pxa2xx driver which required no
  code changes and the addition of kerneldoc for some structure fields
  that were missing it and generating warnings during documentation
  builds as a result"

* tag 'spi-v3.17-rc3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: sh-msiof: Fix transmit-only DMA transfers
  spi/rockchip: Avoid accidentally turning off the clock
  spi: dw: fix kernel crash due to NULL pointer dereference
  spi: dw-pci: fix bug when regs left uninitialized
  spi: davinci: fix SPI_NO_CS functionality
  spi/rockchip: fixup incorrect dma direction setting
  spi/pxa2xx: Add ACPI ID for Intel Braswell
  spi: spi-au1550: fix build failure
  spi: rspi: Fix leaking of unused DMA descriptors
  spi: sh-msiof: Fix leaking of unused DMA descriptors
  spi: Add missing kerneldoc bits
  spi/omap-mcspi: Fix the spi task hangs waiting dma_rx

1 files changed, 58 insertions, 36 deletions

diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index c850dfdfa9e3..ad87a98f8f68 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -472,25 +472,52 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
 	dma_cookie_t cookie;
 	int ret;
 
-	if (tx) {
-		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
-					tx->sgl, tx->nents, DMA_TO_DEVICE,
-					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
-		if (!desc_tx)
-			goto no_dma;
-
-		irq_mask |= SPCR_SPTIE;
-	}
+	/* First prepare and submit the DMA request(s), as this may fail */
 	if (rx) {
 		desc_rx = dmaengine_prep_slave_sg(rspi->master->dma_rx,
 					rx->sgl, rx->nents, DMA_FROM_DEVICE,
 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
-		if (!desc_rx)
-			goto no_dma;
+		if (!desc_rx) {
+			ret = -EAGAIN;
+			goto no_dma_rx;
+		}
+
+		desc_rx->callback = rspi_dma_complete;
+		desc_rx->callback_param = rspi;
+		cookie = dmaengine_submit(desc_rx);
+		if (dma_submit_error(cookie)) {
+			ret = cookie;
+			goto no_dma_rx;
+		}
 
 		irq_mask |= SPCR_SPRIE;
 	}
 
+	if (tx) {
+		desc_tx = dmaengine_prep_slave_sg(rspi->master->dma_tx,
+					tx->sgl, tx->nents, DMA_TO_DEVICE,
+					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+		if (!desc_tx) {
+			ret = -EAGAIN;
+			goto no_dma_tx;
+		}
+
+		if (rx) {
+			/* No callback */
+			desc_tx->callback = NULL;
+		} else {
+			desc_tx->callback = rspi_dma_complete;
+			desc_tx->callback_param = rspi;
+		}
+		cookie = dmaengine_submit(desc_tx);
+		if (dma_submit_error(cookie)) {
+			ret = cookie;
+			goto no_dma_tx;
+		}
+
+		irq_mask |= SPCR_SPTIE;
+	}
+
 	/*
 	 * DMAC needs SPxIE, but if SPxIE is set, the IRQ routine will be
 	 * called. So, this driver disables the IRQ while DMA transfer.
@@ -503,34 +530,24 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
 	rspi_enable_irq(rspi, irq_mask);
 	rspi->dma_callbacked = 0;
 
-	if (rx) {
-		desc_rx->callback = rspi_dma_complete;
-		desc_rx->callback_param = rspi;
-		cookie = dmaengine_submit(desc_rx);
-		if (dma_submit_error(cookie))
-			return cookie;
+	/* Now start DMA */
+	if (rx)
 		dma_async_issue_pending(rspi->master->dma_rx);
-	}
-	if (tx) {
-		if (rx) {
-			/* No callback */
-			desc_tx->callback = NULL;
-		} else {
-			desc_tx->callback = rspi_dma_complete;
-			desc_tx->callback_param = rspi;
-		}
-		cookie = dmaengine_submit(desc_tx);
-		if (dma_submit_error(cookie))
-			return cookie;
+	if (tx)
 		dma_async_issue_pending(rspi->master->dma_tx);
-	}
 
 	ret = wait_event_interruptible_timeout(rspi->wait,
 					       rspi->dma_callbacked, HZ);
 	if (ret > 0 && rspi->dma_callbacked)
 		ret = 0;
-	else if (!ret)
+	else if (!ret) {
+		dev_err(&rspi->master->dev, "DMA timeout\n");
 		ret = -ETIMEDOUT;
+		if (tx)
+			dmaengine_terminate_all(rspi->master->dma_tx);
+		if (rx)
+			dmaengine_terminate_all(rspi->master->dma_rx);
+	}
 
 	rspi_disable_irq(rspi, irq_mask);
 
@@ -541,11 +558,16 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
 
 	return ret;
 
-no_dma:
-	pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
-		     dev_driver_string(&rspi->master->dev),
-		     dev_name(&rspi->master->dev));
-	return -EAGAIN;
+no_dma_tx:
+	if (rx)
+		dmaengine_terminate_all(rspi->master->dma_rx);
+no_dma_rx:
+	if (ret == -EAGAIN) {
+		pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
+			     dev_driver_string(&rspi->master->dev),
+			     dev_name(&rspi->master->dev));
+	}
+	return ret;
 }
 
 static void rspi_receive_init(const struct rspi_data *rspi)