spi_unmap_buf(ctlr, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE);
}
+ ctlr->cur_msg_mapped = false;
+
return 0;
}
#else /* !CONFIG_HAS_DMA */
if (xfer->tx_buf || xfer->rx_buf) {
reinit_completion(&ctlr->xfer_completion);
+fallback_pio:
ret = ctlr->transfer_one(ctlr, msg->spi, xfer);
if (ret < 0) {
+ if (ctlr->cur_msg_mapped &&
+ (xfer->error & SPI_TRANS_FAIL_NO_START)) {
+ __spi_unmap_msg(ctlr, msg);
+ ctlr->fallback = true;
+ xfer->error &= ~SPI_TRANS_FAIL_NO_START;
+ goto fallback_pio;
+ }
+
SPI_STATISTICS_INCREMENT_FIELD(statm,
errors);
SPI_STATISTICS_INCREMENT_FIELD(stats,
spin_lock_irqsave(&ctlr->queue_lock, flags);
ctlr->cur_msg = NULL;
ctlr->cur_msg_prepared = false;
+ ctlr->fallback = false;
kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages);
spin_unlock_irqrestore(&ctlr->queue_lock, flags);
* If the driver does not set this, the SPI core takes the snapshot as
* close to the driver hand-over as possible.
* @irq_flags: Interrupt enable state during PTP system timestamping
+ * @fallback: fallback to pio if dma transfer return failure with
+ * SPI_TRANS_FAIL_NO_START.
*
* Each SPI controller can communicate with one or more @spi_device
* children. These make a small bus, sharing MOSI, MISO and SCK signals
bool auto_runtime_pm;
bool cur_msg_prepared;
bool cur_msg_mapped;
+ bool fallback;
struct completion xfer_completion;
size_t max_dma_len;
* back unset and they need the better resolution.
* @timestamped_post: See above. The reason why both exist is that these
* booleans are also used to keep state in the core SPI logic.
+ * @error: Error status logged by spi controller driver.
*
* SPI transfers always write the same number of bytes as they read.
* Protocol drivers should always provide @rx_buf and/or @tx_buf.
bool timestamped;
struct list_head transfer_list;
+
+#define SPI_TRANS_FAIL_NO_START BIT(0)
+ u16 error;
};
/**