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path: root/drivers/spi/spi-rspi.c
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Diffstat (limited to 'drivers/spi/spi-rspi.c')
-rw-r--r--drivers/spi/spi-rspi.c125
1 files changed, 80 insertions, 45 deletions
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 10112745bb17..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)
- return -EIO;
-
- 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)
- return -EIO;
+ 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);
@@ -540,6 +557,17 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
enable_irq(rspi->rx_irq);
return ret;
+
+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)
@@ -593,8 +621,10 @@ static int rspi_common_transfer(struct rspi_data *rspi,
if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
/* rx_buf can be NULL on RSPI on SH in TX-only Mode */
- return rspi_dma_transfer(rspi, &xfer->tx_sg,
- xfer->rx_buf ? &xfer->rx_sg : NULL);
+ ret = rspi_dma_transfer(rspi, &xfer->tx_sg,
+ xfer->rx_buf ? &xfer->rx_sg : NULL);
+ if (ret != -EAGAIN)
+ return ret;
}
ret = rspi_pio_transfer(rspi, xfer->tx_buf, xfer->rx_buf, xfer->len);
@@ -630,7 +660,6 @@ static int rspi_rz_transfer_one(struct spi_master *master,
struct spi_transfer *xfer)
{
struct rspi_data *rspi = spi_master_get_devdata(master);
- int ret;
rspi_rz_receive_init(rspi);
@@ -649,8 +678,11 @@ static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
{
int ret;
- if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer))
- return rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
+ if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
+ ret = rspi_dma_transfer(rspi, &xfer->tx_sg, NULL);
+ if (ret != -EAGAIN)
+ return ret;
+ }
ret = rspi_pio_transfer(rspi, xfer->tx_buf, NULL, xfer->len);
if (ret < 0)
@@ -664,8 +696,11 @@ static int qspi_transfer_out(struct rspi_data *rspi, struct spi_transfer *xfer)
static int qspi_transfer_in(struct rspi_data *rspi, struct spi_transfer *xfer)
{
- if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer))
- return rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
+ if (rspi->master->can_dma && __rspi_can_dma(rspi, xfer)) {
+ int ret = rspi_dma_transfer(rspi, NULL, &xfer->rx_sg);
+ if (ret != -EAGAIN)
+ return ret;
+ }
return rspi_pio_transfer(rspi, NULL, xfer->rx_buf, xfer->len);
}
@@ -927,19 +962,19 @@ static int rspi_request_dma(struct device *dev, struct spi_master *master,
return 0;
}
-static void rspi_release_dma(struct rspi_data *rspi)
+static void rspi_release_dma(struct spi_master *master)
{
- if (rspi->master->dma_tx)
- dma_release_channel(rspi->master->dma_tx);
- if (rspi->master->dma_rx)
- dma_release_channel(rspi->master->dma_rx);
+ if (master->dma_tx)
+ dma_release_channel(master->dma_tx);
+ if (master->dma_rx)
+ dma_release_channel(master->dma_rx);
}
static int rspi_remove(struct platform_device *pdev)
{
struct rspi_data *rspi = platform_get_drvdata(pdev);
- rspi_release_dma(rspi);
+ rspi_release_dma(rspi->master);
pm_runtime_disable(&pdev->dev);
return 0;
@@ -1141,7 +1176,7 @@ static int rspi_probe(struct platform_device *pdev)
return 0;
error3:
- rspi_release_dma(rspi);
+ rspi_release_dma(master);
error2:
pm_runtime_disable(&pdev->dev);
error1: