[1/2] spi: atmel: Switch to transfer_one transfer method

Commit Message

Dan Sneddon June 2, 2021, 4:08 p.m. UTC

Switch from using our own transfer_one_message routine to using the one
provided by the SPI core.

Signed-off-by: Dan Sneddon <[e-mail]>
---
 drivers/spi/spi-atmel.c | 124 +++++++++++-----------------------------
 1 file changed, 33 insertions(+), 91 deletions(-)

Comments

Mark Brown June 3, 2021, 6:41 p.m. UTC | #1

On Wed, 2 Jun 2021 09:08:14 -0700, Dan Sneddon wrote:
> Switch from using our own transfer_one_message routine to using the one
> provided by the SPI core.

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next

Thanks!

[1/2] spi: atmel: Switch to transfer_one transfer method
      commit: 5fa5e6dec762305a783e918a90a05369fc10e346
[2/2] spi: atmel: Reduce spin lock usage
      commit: 4abd641501663493764949f045ebf9f8c0da0307

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Patch

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 7cd5fe00dfc1..0e693e72c922 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -863,7 +863,6 @@  static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
  * lock is held, spi irq is blocked
  */
 static void atmel_spi_pdc_next_xfer(struct spi_master *master,
-					struct spi_message *msg,
 					struct spi_transfer *xfer)
 {
 	struct atmel_spi	*as = spi_master_get_devdata(master);
@@ -879,12 +878,12 @@  static void atmel_spi_pdc_next_xfer(struct spi_master *master,
 	spi_writel(as, RPR, rx_dma);
 	spi_writel(as, TPR, tx_dma);
 
-	if (msg->spi->bits_per_word > 8)
+	if (xfer->bits_per_word > 8)
 		len >>= 1;
 	spi_writel(as, RCR, len);
 	spi_writel(as, TCR, len);
 
-	dev_dbg(&msg->spi->dev,
+	dev_dbg(&master->dev,
 		"  start xfer %p: len %u tx %p/%08llx rx %p/%08llx\n",
 		xfer, xfer->len, xfer->tx_buf,
 		(unsigned long long)xfer->tx_dma, xfer->rx_buf,
@@ -898,12 +897,12 @@  static void atmel_spi_pdc_next_xfer(struct spi_master *master,
 		spi_writel(as, RNPR, rx_dma);
 		spi_writel(as, TNPR, tx_dma);
 
-		if (msg->spi->bits_per_word > 8)
+		if (xfer->bits_per_word > 8)
 			len >>= 1;
 		spi_writel(as, RNCR, len);
 		spi_writel(as, TNCR, len);
 
-		dev_dbg(&msg->spi->dev,
+		dev_dbg(&master->dev,
 			"  next xfer %p: len %u tx %p/%08llx rx %p/%08llx\n",
 			xfer, xfer->len, xfer->tx_buf,
 			(unsigned long long)xfer->tx_dma, xfer->rx_buf,
@@ -1273,12 +1272,28 @@  static int atmel_spi_setup(struct spi_device *spi)
 	return 0;
 }
 
+static void atmel_spi_set_cs(struct spi_device *spi, bool enable)
+{
+	struct atmel_spi *as = spi_master_get_devdata(spi->master);
+	/* the core doesn't really pass us enable/disable, but CS HIGH vs CS LOW
+	 * since we already have routines for activate/deactivate translate
+	 * high/low to active/inactive
+	 */
+	enable = (!!(spi->mode & SPI_CS_HIGH) == enable);
+
+	if (enable) {
+		cs_activate(as, spi);
+	} else {
+		cs_deactivate(as, spi);
+	}
+
+}
+
 static int atmel_spi_one_transfer(struct spi_master *master,
-					struct spi_message *msg,
+					struct spi_device *spi,
 					struct spi_transfer *xfer)
 {
 	struct atmel_spi	*as;
-	struct spi_device	*spi = msg->spi;
 	u8			bits;
 	u32			len;
 	struct atmel_spi_device	*asd;
@@ -1287,11 +1302,8 @@  static int atmel_spi_one_transfer(struct spi_master *master,
 	unsigned long		dma_timeout;
 
 	as = spi_master_get_devdata(master);
-
-	if (!(xfer->tx_buf || xfer->rx_buf) && xfer->len) {
-		dev_dbg(&spi->dev, "missing rx or tx buf\n");
-		return -EINVAL;
-	}
+	/* This lock was orignally taken in atmel_spi_trasfer_one_message */
+	atmel_spi_lock(as);
 
 	asd = spi->controller_state;
 	bits = (asd->csr >> 4) & 0xf;
@@ -1305,13 +1317,13 @@  static int atmel_spi_one_transfer(struct spi_master *master,
 	 * DMA map early, for performance (empties dcache ASAP) and
 	 * better fault reporting.
 	 */
-	if ((!msg->is_dma_mapped)
+	if ((!master->cur_msg_mapped)
 		&& as->use_pdc) {
 		if (atmel_spi_dma_map_xfer(as, xfer) < 0)
 			return -ENOMEM;
 	}
 
-	atmel_spi_set_xfer_speed(as, msg->spi, xfer);
+	atmel_spi_set_xfer_speed(as, spi, xfer);
 
 	as->done_status = 0;
 	as->current_transfer = xfer;
@@ -1320,7 +1332,7 @@  static int atmel_spi_one_transfer(struct spi_master *master,
 		reinit_completion(&as->xfer_completion);
 
 		if (as->use_pdc) {
-			atmel_spi_pdc_next_xfer(master, msg, xfer);
+			atmel_spi_pdc_next_xfer(master, xfer);
 		} else if (atmel_spi_use_dma(as, xfer)) {
 			len = as->current_remaining_bytes;
 			ret = atmel_spi_next_xfer_dma_submit(master,
@@ -1328,7 +1340,8 @@  static int atmel_spi_one_transfer(struct spi_master *master,
 			if (ret) {
 				dev_err(&spi->dev,
 					"unable to use DMA, fallback to PIO\n");
-				atmel_spi_next_xfer_pio(master, xfer);
+				as->done_status = ret;
+				break;
 			} else {
 				as->current_remaining_bytes -= len;
 				if (as->current_remaining_bytes < 0)
@@ -1381,90 +1394,18 @@  static int atmel_spi_one_transfer(struct spi_master *master,
 		} else if (atmel_spi_use_dma(as, xfer)) {
 			atmel_spi_stop_dma(master);
 		}
-
-		if (!msg->is_dma_mapped
-			&& as->use_pdc)
-			atmel_spi_dma_unmap_xfer(master, xfer);
-
-		return 0;
-
-	} else {
-		/* only update length if no error */
-		msg->actual_length += xfer->len;
 	}
 
-	if (!msg->is_dma_mapped
+	if (!master->cur_msg_mapped
 		&& as->use_pdc)
 		atmel_spi_dma_unmap_xfer(master, xfer);
 
-	spi_transfer_delay_exec(xfer);
-
-	if (xfer->cs_change) {
-		if (list_is_last(&xfer->transfer_list,
-				 &msg->transfers)) {
-			as->keep_cs = true;
-		} else {
-			cs_deactivate(as, msg->spi);
-			udelay(10);
-			cs_activate(as, msg->spi);
-		}
-	}
-
-	return 0;
-}
-
-static int atmel_spi_transfer_one_message(struct spi_master *master,
-						struct spi_message *msg)
-{
-	struct atmel_spi *as;
-	struct spi_transfer *xfer;
-	struct spi_device *spi = msg->spi;
-	int ret = 0;
-
-	as = spi_master_get_devdata(master);
-
-	dev_dbg(&spi->dev, "new message %p submitted for %s\n",
-					msg, dev_name(&spi->dev));
-
-	atmel_spi_lock(as);
-	cs_activate(as, spi);
-
-	as->keep_cs = false;
-
-	msg->status = 0;
-	msg->actual_length = 0;
-
-	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
-		trace_spi_transfer_start(msg, xfer);
-
-		ret = atmel_spi_one_transfer(master, msg, xfer);
-		if (ret)
-			goto msg_done;
-
-		trace_spi_transfer_stop(msg, xfer);
-	}
-
 	if (as->use_pdc)
 		atmel_spi_disable_pdc_transfer(as);
 
-	list_for_each_entry(xfer, &msg->transfers, transfer_list) {
-		dev_dbg(&spi->dev,
-			"  xfer %p: len %u tx %p/%pad rx %p/%pad\n",
-			xfer, xfer->len,
-			xfer->tx_buf, &xfer->tx_dma,
-			xfer->rx_buf, &xfer->rx_dma);
-	}
-
-msg_done:
-	if (!as->keep_cs)
-		cs_deactivate(as, msg->spi);
-
 	atmel_spi_unlock(as);
 
-	msg->status = as->done_status;
-	spi_finalize_current_message(spi->master);
-
-	return ret;
+	return as->done_status;
 }
 
 static void atmel_spi_cleanup(struct spi_device *spi)
@@ -1554,7 +1495,8 @@  static int atmel_spi_probe(struct platform_device *pdev)
 	master->num_chipselect = 4;
 	master->setup = atmel_spi_setup;
 	master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX);
-	master->transfer_one_message = atmel_spi_transfer_one_message;
+	master->transfer_one = atmel_spi_one_transfer;
+	master->set_cs = atmel_spi_set_cs;
 	master->cleanup = atmel_spi_cleanup;
 	master->auto_runtime_pm = true;
 	master->max_dma_len = SPI_MAX_DMA_XFER;