[PATCH 0/5] spi: atmel: enhance the DMA handling

[PATCH 0/5] spi: atmel: enhance the DMA handling

[Nicolas Ferre]

Use the dummy buffer handling and DMA mapping core infrastructure to simplify
spi-atmel driver.
By using these frameworks we also fix the use of any kind of memory with
dmaengine. This work was triggered by issues encountered while using UBI/UBIFS
on a serial flash.

Some good ideas of this series have been inspired by spi-rspi.c and commits by
Geert Uytterhoeven.

I have a side question still: is the is_dma_mapped tag still used and considered into
the core spi routines or is it always the driver itself that have to deal with
it (so how to do with the can_dma() routine)?

Cyrille Pitchen (1):
  spi: atmel: Use SPI core DMA mapping framework

Nicolas Ferre (4):
  spi: atmel: trivial: move info banner to latest probe action
  spi: atmel: Use core SPI_MASTER_MUST_[RT]X handling
  spi: atmel: trivial: remove unused fields in DMA structure
  spi: atmel: remove the use of private channel fields

 drivers/spi/spi-atmel.c | 268 ++++++++++++++++++------------------------------
 1 file changed, 98 insertions(+), 170 deletions(-)

-- 
2.9.0

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 1/5] spi: atmel: trivial: move info banner to latest probe action

[Nicolas Ferre]

The info banner is here to tell that everything went well, so place
it at the very end of the probe function.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/spi/spi-atmel.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index a038ffe90766..68e22bf94647 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1658,10 +1658,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
 		spi_writel(as, CR, SPI_BIT(FIFOEN));
 	}
 
-	/* go! */
-	dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n",
-			(unsigned long)regs->start, irq);
-
 	pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_active(&pdev->dev);
@@ -1671,6 +1667,10 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_free_dma;
 
+	/* go! */
+	dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n",
+			(unsigned long)regs->start, irq);
+
 	return 0;
 
 out_free_dma:
-- 
2.9.0

[PATCH 2/5] spi: atmel: Use core SPI_MASTER_MUST_[RT]X handling

[Nicolas Ferre]

We need both RX and TX data for each transfer in any case (PIO, PDC, DMA).
So convert the driver to the core dummy buffer handling with the
SPI_MASTER_MUST_RX/SPI_MASTER_MUST_TX infrastructure.

This move changes the maximum PDC/DMA buffer handling to 65535 bytes
instead of a single page and sets master->max_dma_len to this value.

All dummy buffer management is removed from the driver.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/spi/spi-atmel.c | 131 +++++++++++++-----------------------------------
 1 file changed, 35 insertions(+), 96 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 68e22bf94647..d0a56e11e148 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -304,10 +304,6 @@ struct atmel_spi {
 
 	struct completion	xfer_completion;
 
-	/* scratch buffer */
-	void			*buffer;
-	dma_addr_t		buffer_dma;
-
 	struct atmel_spi_caps	caps;
 
 	bool			use_dma;
@@ -328,7 +324,7 @@ struct atmel_spi_device {
 	u32			csr;
 };
 
-#define BUFFER_SIZE		PAGE_SIZE
+#define SPI_MAX_DMA_XFER	65535 /* true for both PDC and DMA */
 #define INVALID_DMA_ADDRESS	0xffffffff
 
 /*
@@ -613,14 +609,10 @@ static void atmel_spi_next_xfer_single(struct spi_master *master,
 		cpu_relax();
 	}
 
-	if (xfer->tx_buf) {
-		if (xfer->bits_per_word > 8)
-			spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos));
-		else
-			spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos));
-	} else {
-		spi_writel(as, TDR, 0);
-	}
+	if (xfer->bits_per_word > 8)
+		spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos));
+	else
+		spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos));
 
 	dev_dbg(master->dev.parent,
 		"  start pio xfer %p: len %u tx %p rx %p bitpw %d\n",
@@ -667,17 +659,12 @@ static void atmel_spi_next_xfer_fifo(struct spi_master *master,
 
 	/* Fill TX FIFO */
 	while (num_data >= 2) {
-		if (xfer->tx_buf) {
-			if (xfer->bits_per_word > 8) {
-				td0 = *words++;
-				td1 = *words++;
-			} else {
-				td0 = *bytes++;
-				td1 = *bytes++;
-			}
+		if (xfer->bits_per_word > 8) {
+			td0 = *words++;
+			td1 = *words++;
 		} else {
-			td0 = 0;
-			td1 = 0;
+			td0 = *bytes++;
+			td1 = *bytes++;
 		}
 
 		spi_writel(as, TDR, (td1 << 16) | td0);
@@ -685,14 +672,10 @@ static void atmel_spi_next_xfer_fifo(struct spi_master *master,
 	}
 
 	if (num_data) {
-		if (xfer->tx_buf) {
-			if (xfer->bits_per_word > 8)
-				td0 = *words++;
-			else
-				td0 = *bytes++;
-		} else {
-			td0 = 0;
-		}
+		if (xfer->bits_per_word > 8)
+			td0 = *words++;
+		else
+			td0 = *bytes++;
 
 		spi_writew(as, TDR, td0);
 		num_data--;
@@ -751,24 +734,14 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 
 	/* prepare the RX dma transfer */
 	sg_init_table(&as->dma.sgrx, 1);
-	if (xfer->rx_buf) {
-		as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
-	} else {
-		as->dma.sgrx.dma_address = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-	}
+	as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
 
 	/* prepare the TX dma transfer */
 	sg_init_table(&as->dma.sgtx, 1);
-	if (xfer->tx_buf) {
-		as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
-	} else {
-		as->dma.sgtx.dma_address = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-		memset(as->buffer, 0, len);
-	}
+	as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
+
+	if (len > master->max_dma_len)
+		len = master->max_dma_len;
 
 	sg_dma_len(&as->dma.sgtx) = len;
 	sg_dma_len(&as->dma.sgrx) = len;
@@ -835,25 +808,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master,
 	struct atmel_spi	*as = spi_master_get_devdata(master);
 	u32			len = *plen;
 
-	/* use scratch buffer only when rx or tx data is unspecified */
-	if (xfer->rx_buf)
-		*rx_dma = xfer->rx_dma + xfer->len - *plen;
-	else {
-		*rx_dma = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-	}
-
-	if (xfer->tx_buf)
-		*tx_dma = xfer->tx_dma + xfer->len - *plen;
-	else {
-		*tx_dma = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-		memset(as->buffer, 0, len);
-		dma_sync_single_for_device(&as->pdev->dev,
-				as->buffer_dma, len, DMA_TO_DEVICE);
-	}
+	*rx_dma = xfer->rx_dma + xfer->len - *plen;
+	*tx_dma = xfer->tx_dma + xfer->len - *plen;
+	if (len > master->max_dma_len)
+		len = master->max_dma_len;
 
 	*plen = len;
 }
@@ -1027,16 +985,12 @@ atmel_spi_pump_single_data(struct atmel_spi *as, struct spi_transfer *xfer)
 	u16		*rxp16;
 	unsigned long	xfer_pos = xfer->len - as->current_remaining_bytes;
 
-	if (xfer->rx_buf) {
-		if (xfer->bits_per_word > 8) {
-			rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos);
-			*rxp16 = spi_readl(as, RDR);
-		} else {
-			rxp = ((u8 *)xfer->rx_buf) + xfer_pos;
-			*rxp = spi_readl(as, RDR);
-		}
+	if (xfer->bits_per_word > 8) {
+		rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos);
+		*rxp16 = spi_readl(as, RDR);
 	} else {
-		spi_readl(as, RDR);
+		rxp = ((u8 *)xfer->rx_buf) + xfer_pos;
+		*rxp = spi_readl(as, RDR);
 	}
 	if (xfer->bits_per_word > 8) {
 		if (as->current_remaining_bytes > 2)
@@ -1075,12 +1029,10 @@ atmel_spi_pump_fifo_data(struct atmel_spi *as, struct spi_transfer *xfer)
 	/* Read data */
 	while (num_data) {
 		rd = spi_readl(as, RDR);
-		if (xfer->rx_buf) {
-			if (xfer->bits_per_word > 8)
-				*words++ = rd;
-			else
-				*bytes++ = rd;
-		}
+		if (xfer->bits_per_word > 8)
+			*words++ = rd;
+		else
+			*bytes++ = rd;
 		num_data--;
 	}
 }
@@ -1562,29 +1514,22 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	master->bus_num = pdev->id;
 	master->num_chipselect = master->dev.of_node ? 0 : 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->cleanup = atmel_spi_cleanup;
 	master->auto_runtime_pm = true;
+	master->max_dma_len = SPI_MAX_DMA_XFER;
 	platform_set_drvdata(pdev, master);
 
 	as = spi_master_get_devdata(master);
 
-	/*
-	 * Scratch buffer is used for throwaway rx and tx data.
-	 * It's coherent to minimize dcache pollution.
-	 */
-	as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE,
-					&as->buffer_dma, GFP_KERNEL);
-	if (!as->buffer)
-		goto out_free;
-
 	spin_lock_init(&as->lock);
 
 	as->pdev = pdev;
 	as->regs = devm_ioremap_resource(&pdev->dev, regs);
 	if (IS_ERR(as->regs)) {
 		ret = PTR_ERR(as->regs);
-		goto out_free_buffer;
+		goto out_unmap_regs;
 	}
 	as->phybase = regs->start;
 	as->irq = irq;
@@ -1685,9 +1630,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	clk_disable_unprepare(clk);
 out_free_irq:
 out_unmap_regs:
-out_free_buffer:
-	dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
-			as->buffer_dma);
 out_free:
 	spi_master_put(master);
 	return ret;
@@ -1712,9 +1654,6 @@ static int atmel_spi_remove(struct platform_device *pdev)
 	spi_readl(as, SR);
 	spin_unlock_irq(&as->lock);
 
-	dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
-			as->buffer_dma);
-
 	clk_disable_unprepare(as->clk);
 
 	pm_runtime_put_noidle(&pdev->dev);
-- 
2.9.0

[PATCH 3/5] spi: atmel: Use SPI core DMA mapping framework

[Nicolas Ferre]

From: Cyrille Pitchen <cyrille.pitchen@atmel.com>

Use the SPI core DMA mapping framework instead of our own
in case of DMA support. PDC support is not converted to this
framework.

The driver is now able to transfer a complete sg list through DMA.
This eventually fix an issue with vmalloc'ed DMA memory that is
provided for example by UBI/UBIFS layers.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
[nicolas.ferre@atmel.com: restrict the use to non-PDC DMA]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/spi/spi-atmel.c | 57 ++++++++++++++++++++++---------------------------
 1 file changed, 25 insertions(+), 32 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index d0a56e11e148..f62bc2d27c9e 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -268,8 +268,6 @@
 struct atmel_spi_dma {
 	struct dma_chan			*chan_rx;
 	struct dma_chan			*chan_tx;
-	struct scatterlist		sgrx;
-	struct scatterlist		sgtx;
 	struct dma_async_tx_descriptor	*data_desc_rx;
 	struct dma_async_tx_descriptor	*data_desc_tx;
 
@@ -454,6 +452,15 @@ static inline bool atmel_spi_use_dma(struct atmel_spi *as,
 	return as->use_dma && xfer->len >= DMA_MIN_BYTES;
 }
 
+static bool atmel_spi_can_dma(struct spi_master *master,
+			      struct spi_device *spi,
+			      struct spi_transfer *xfer)
+{
+	struct atmel_spi *as = spi_master_get_devdata(master);
+
+	return atmel_spi_use_dma(as, xfer);
+}
+
 static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 				struct dma_slave_config *slave_config,
 				u8 bits_per_word)
@@ -721,7 +728,6 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 	struct dma_async_tx_descriptor *txdesc;
 	struct dma_slave_config	slave_config;
 	dma_cookie_t		cookie;
-	u32	len = *plen;
 
 	dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n");
 
@@ -732,34 +738,22 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 	/* release lock for DMA operations */
 	atmel_spi_unlock(as);
 
-	/* prepare the RX dma transfer */
-	sg_init_table(&as->dma.sgrx, 1);
-	as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
-
-	/* prepare the TX dma transfer */
-	sg_init_table(&as->dma.sgtx, 1);
-	as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
-
-	if (len > master->max_dma_len)
-		len = master->max_dma_len;
-
-	sg_dma_len(&as->dma.sgtx) = len;
-	sg_dma_len(&as->dma.sgrx) = len;
-
-	*plen = len;
+	*plen = xfer->len;
 
 	if (atmel_spi_dma_slave_config(as, &slave_config,
 				       xfer->bits_per_word))
 		goto err_exit;
 
 	/* Send both scatterlists */
-	rxdesc = dmaengine_prep_slave_sg(rxchan, &as->dma.sgrx, 1,
+	rxdesc = dmaengine_prep_slave_sg(rxchan,
+					 xfer->rx_sg.sgl, xfer->rx_sg.nents,
 					 DMA_FROM_DEVICE,
 					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!rxdesc)
 		goto err_dma;
 
-	txdesc = dmaengine_prep_slave_sg(txchan, &as->dma.sgtx, 1,
+	txdesc = dmaengine_prep_slave_sg(txchan,
+					 xfer->tx_sg.sgl, xfer->tx_sg.nents,
 					 DMA_TO_DEVICE,
 					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!txdesc)
@@ -805,15 +799,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master,
 				dma_addr_t *rx_dma,
 				u32 *plen)
 {
-	struct atmel_spi	*as = spi_master_get_devdata(master);
-	u32			len = *plen;
-
 	*rx_dma = xfer->rx_dma + xfer->len - *plen;
 	*tx_dma = xfer->tx_dma + xfer->len - *plen;
-	if (len > master->max_dma_len)
-		len = master->max_dma_len;
-
-	*plen = len;
+	if (*plen > master->max_dma_len)
+		*plen = master->max_dma_len;
 }
 
 static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
@@ -1253,7 +1242,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 	 * better fault reporting.
 	 */
 	if ((!msg->is_dma_mapped)
-		&& (atmel_spi_use_dma(as, xfer)	|| as->use_pdc)) {
+		&& as->use_pdc) {
 		if (atmel_spi_dma_map_xfer(as, xfer) < 0)
 			return -ENOMEM;
 	}
@@ -1330,7 +1319,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 		}
 
 		if (!msg->is_dma_mapped
-			&& (atmel_spi_use_dma(as, xfer) || as->use_pdc))
+			&& as->use_pdc)
 			atmel_spi_dma_unmap_xfer(master, xfer);
 
 		return 0;
@@ -1341,7 +1330,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 	}
 
 	if (!msg->is_dma_mapped
-		&& (atmel_spi_use_dma(as, xfer) || as->use_pdc))
+		&& as->use_pdc)
 		atmel_spi_dma_unmap_xfer(master, xfer);
 
 	if (xfer->delay_usecs)
@@ -1519,6 +1508,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	master->cleanup = atmel_spi_cleanup;
 	master->auto_runtime_pm = true;
 	master->max_dma_len = SPI_MAX_DMA_XFER;
+	master->can_dma = atmel_spi_can_dma;
 	platform_set_drvdata(pdev, master);
 
 	as = spi_master_get_devdata(master);
@@ -1555,10 +1545,13 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	as->use_pdc = false;
 	if (as->caps.has_dma_support) {
 		ret = atmel_spi_configure_dma(as);
-		if (ret == 0)
+		if (ret == 0) {
+			master->dma_tx = as->dma.chan_tx;
+			master->dma_rx = as->dma.chan_rx;
 			as->use_dma = true;
-		else if (ret == -EPROBE_DEFER)
+		} else if (ret == -EPROBE_DEFER) {
 			return ret;
+		}
 	} else {
 		as->use_pdc = true;
 	}
-- 
2.9.0

[PATCH 4/5] spi: atmel: trivial: remove unused fields in DMA structure

[Nicolas Ferre]

The atmel_spi_dma structure was cluttered with unused fields relative
to older DMA channel selection API. Remove them.

Signed-off-by: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
---
 drivers/spi/spi-atmel.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index f62bc2d27c9e..f3a225585575 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -268,10 +268,6 @@
 struct atmel_spi_dma {
 	struct dma_chan			*chan_rx;
 	struct dma_chan			*chan_tx;
-	struct dma_async_tx_descriptor	*data_desc_rx;
-	struct dma_async_tx_descriptor	*data_desc_tx;
-
-	struct at_dma_slave	dma_slave;
 };
 
 struct atmel_spi_caps {
-- 
2.9.0

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[PATCH 5/5] spi: atmel: remove the use of private channel fields

[Nicolas Ferre]

For DMA transfers, we now use the core DMA framework which provides
channel fields in the spi_master structure. Remove the private channels
from atmel_spi stucture which were located in a sub-structure. This
last one (atmel_spi_dma) which is now empty is also removed.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
---
 drivers/spi/spi-atmel.c | 86 ++++++++++++++++++++++++-------------------------
 1 file changed, 43 insertions(+), 43 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index f3a225585575..0e7712bac3b6 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -265,11 +265,6 @@
 
 #define AUTOSUSPEND_TIMEOUT	2000
 
-struct atmel_spi_dma {
-	struct dma_chan			*chan_rx;
-	struct dma_chan			*chan_tx;
-};
-
 struct atmel_spi_caps {
 	bool	is_spi2;
 	bool	has_wdrbt;
@@ -303,8 +298,6 @@ struct atmel_spi {
 	bool			use_dma;
 	bool			use_pdc;
 	bool			use_cs_gpios;
-	/* dmaengine data */
-	struct atmel_spi_dma	dma;
 
 	bool			keep_cs;
 	bool			cs_active;
@@ -461,6 +454,7 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 				struct dma_slave_config *slave_config,
 				u8 bits_per_word)
 {
+	struct spi_master *master = platform_get_drvdata(as->pdev);
 	int err = 0;
 
 	if (bits_per_word > 8) {
@@ -492,7 +486,7 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 	 * path works the same whether FIFOs are available (and enabled) or not.
 	 */
 	slave_config->direction = DMA_MEM_TO_DEV;
-	if (dmaengine_slave_config(as->dma.chan_tx, slave_config)) {
+	if (dmaengine_slave_config(master->dma_tx, slave_config)) {
 		dev_err(&as->pdev->dev,
 			"failed to configure tx dma channel\n");
 		err = -EINVAL;
@@ -507,7 +501,7 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 	 * enabled) or not.
 	 */
 	slave_config->direction = DMA_DEV_TO_MEM;
-	if (dmaengine_slave_config(as->dma.chan_rx, slave_config)) {
+	if (dmaengine_slave_config(master->dma_rx, slave_config)) {
 		dev_err(&as->pdev->dev,
 			"failed to configure rx dma channel\n");
 		err = -EINVAL;
@@ -516,7 +510,8 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 	return err;
 }
 
-static int atmel_spi_configure_dma(struct atmel_spi *as)
+static int atmel_spi_configure_dma(struct spi_master *master,
+				   struct atmel_spi *as)
 {
 	struct dma_slave_config	slave_config;
 	struct device *dev = &as->pdev->dev;
@@ -526,26 +521,26 @@ static int atmel_spi_configure_dma(struct atmel_spi *as)
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 
-	as->dma.chan_tx = dma_request_slave_channel_reason(dev, "tx");
-	if (IS_ERR(as->dma.chan_tx)) {
-		err = PTR_ERR(as->dma.chan_tx);
+	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
+	if (IS_ERR(master->dma_tx)) {
+		err = PTR_ERR(master->dma_tx);
 		if (err == -EPROBE_DEFER) {
 			dev_warn(dev, "no DMA channel available at the moment\n");
-			return err;
+			goto error_clear;
 		}
 		dev_err(dev,
 			"DMA TX channel not available, SPI unable to use DMA\n");
 		err = -EBUSY;
-		goto error;
+		goto error_clear;
 	}
 
 	/*
 	 * No reason to check EPROBE_DEFER here since we have already requested
 	 * tx channel. If it fails here, it's for another reason.
 	 */
-	as->dma.chan_rx = dma_request_slave_channel(dev, "rx");
+	master->dma_rx = dma_request_slave_channel(dev, "rx");
 
-	if (!as->dma.chan_rx) {
+	if (!master->dma_rx) {
 		dev_err(dev,
 			"DMA RX channel not available, SPI unable to use DMA\n");
 		err = -EBUSY;
@@ -558,31 +553,38 @@ static int atmel_spi_configure_dma(struct atmel_spi *as)
 
 	dev_info(&as->pdev->dev,
 			"Using %s (tx) and %s (rx) for DMA transfers\n",
-			dma_chan_name(as->dma.chan_tx),
-			dma_chan_name(as->dma.chan_rx));
+			dma_chan_name(master->dma_tx),
+			dma_chan_name(master->dma_rx));
+
 	return 0;
 error:
-	if (as->dma.chan_rx)
-		dma_release_channel(as->dma.chan_rx);
-	if (!IS_ERR(as->dma.chan_tx))
-		dma_release_channel(as->dma.chan_tx);
+	if (master->dma_rx)
+		dma_release_channel(master->dma_rx);
+	if (!IS_ERR(master->dma_tx))
+		dma_release_channel(master->dma_tx);
+error_clear:
+	master->dma_tx = master->dma_rx = NULL;
 	return err;
 }
 
-static void atmel_spi_stop_dma(struct atmel_spi *as)
+static void atmel_spi_stop_dma(struct spi_master *master)
 {
-	if (as->dma.chan_rx)
-		dmaengine_terminate_all(as->dma.chan_rx);
-	if (as->dma.chan_tx)
-		dmaengine_terminate_all(as->dma.chan_tx);
+	if (master->dma_rx)
+		dmaengine_terminate_all(master->dma_rx);
+	if (master->dma_tx)
+		dmaengine_terminate_all(master->dma_tx);
 }
 
-static void atmel_spi_release_dma(struct atmel_spi *as)
+static void atmel_spi_release_dma(struct spi_master *master)
 {
-	if (as->dma.chan_rx)
-		dma_release_channel(as->dma.chan_rx);
-	if (as->dma.chan_tx)
-		dma_release_channel(as->dma.chan_tx);
+	if (master->dma_rx) {
+		dma_release_channel(master->dma_rx);
+		master->dma_rx = NULL;
+	}
+	if (master->dma_tx) {
+		dma_release_channel(master->dma_tx);
+		master->dma_tx = NULL;
+	}
 }
 
 /* This function is called by the DMA driver from tasklet context */
@@ -718,8 +720,8 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 				u32 *plen)
 {
 	struct atmel_spi	*as = spi_master_get_devdata(master);
-	struct dma_chan		*rxchan = as->dma.chan_rx;
-	struct dma_chan		*txchan = as->dma.chan_tx;
+	struct dma_chan		*rxchan = master->dma_rx;
+	struct dma_chan		*txchan = master->dma_tx;
 	struct dma_async_tx_descriptor *rxdesc;
 	struct dma_async_tx_descriptor *txdesc;
 	struct dma_slave_config	slave_config;
@@ -783,7 +785,7 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 
 err_dma:
 	spi_writel(as, IDR, SPI_BIT(OVRES));
-	atmel_spi_stop_dma(as);
+	atmel_spi_stop_dma(master);
 err_exit:
 	atmel_spi_lock(as);
 	return -ENOMEM;
@@ -1311,7 +1313,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 			spi_readl(as, SR);
 
 		} else if (atmel_spi_use_dma(as, xfer)) {
-			atmel_spi_stop_dma(as);
+			atmel_spi_stop_dma(master);
 		}
 
 		if (!msg->is_dma_mapped
@@ -1540,10 +1542,8 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	as->use_dma = false;
 	as->use_pdc = false;
 	if (as->caps.has_dma_support) {
-		ret = atmel_spi_configure_dma(as);
+		ret = atmel_spi_configure_dma(master, as);
 		if (ret == 0) {
-			master->dma_tx = as->dma.chan_tx;
-			master->dma_rx = as->dma.chan_rx;
 			as->use_dma = true;
 		} else if (ret == -EPROBE_DEFER) {
 			return ret;
@@ -1612,7 +1612,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	pm_runtime_set_suspended(&pdev->dev);
 
 	if (as->use_dma)
-		atmel_spi_release_dma(as);
+		atmel_spi_release_dma(master);
 
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
@@ -1634,8 +1634,8 @@ static int atmel_spi_remove(struct platform_device *pdev)
 	/* reset the hardware and block queue progress */
 	spin_lock_irq(&as->lock);
 	if (as->use_dma) {
-		atmel_spi_stop_dma(as);
-		atmel_spi_release_dma(as);
+		atmel_spi_stop_dma(master);
+		atmel_spi_release_dma(master);
 	}
 
 	spi_writel(as, CR, SPI_BIT(SWRST));
-- 
2.9.0

Re: [PATCH 1/5] spi: atmel: trivial: move info banner to latest probe action

[Mark Brown]

[-- Attachment #1: Type: text/plain, Size: 301 bytes --]

On Thu, Nov 24, 2016 at 12:24:57PM +0100, Nicolas Ferre wrote:
> The info banner is here to tell that everything went well, so place
> it at the very end of the probe function.

Really we should just drop this, the banner is only telling us things
enumerated from DT so it's adding noise to the boot.

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 455 bytes --]

Applied "spi: atmel: remove the use of private channel fields" to the spi tree

[Mark Brown]

The patch

   spi: atmel: remove the use of private channel fields

has been applied to the spi tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

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

>From 768f3d9d80d28c0d2d3cb5774f220c04d4d3c6d8 Mon Sep 17 00:00:00 2001
From: Nicolas Ferre <nicolas.ferre@atmel.com>
Date: Thu, 24 Nov 2016 12:25:01 +0100
Subject: [PATCH] spi: atmel: remove the use of private channel fields

For DMA transfers, we now use the core DMA framework which provides
channel fields in the spi_master structure. Remove the private channels
from atmel_spi stucture which were located in a sub-structure. This
last one (atmel_spi_dma) which is now empty is also removed.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/spi-atmel.c | 86 ++++++++++++++++++++++++-------------------------
 1 file changed, 43 insertions(+), 43 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 1a21bc6f7d7a..3e537ed5cd75 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -265,11 +265,6 @@
 
 #define AUTOSUSPEND_TIMEOUT	2000
 
-struct atmel_spi_dma {
-	struct dma_chan			*chan_rx;
-	struct dma_chan			*chan_tx;
-};
-
 struct atmel_spi_caps {
 	bool	is_spi2;
 	bool	has_wdrbt;
@@ -302,8 +297,6 @@ struct atmel_spi {
 	bool			use_dma;
 	bool			use_pdc;
 	bool			use_cs_gpios;
-	/* dmaengine data */
-	struct atmel_spi_dma	dma;
 
 	bool			keep_cs;
 	bool			cs_active;
@@ -460,6 +453,7 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 				struct dma_slave_config *slave_config,
 				u8 bits_per_word)
 {
+	struct spi_master *master = platform_get_drvdata(as->pdev);
 	int err = 0;
 
 	if (bits_per_word > 8) {
@@ -491,7 +485,7 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 	 * path works the same whether FIFOs are available (and enabled) or not.
 	 */
 	slave_config->direction = DMA_MEM_TO_DEV;
-	if (dmaengine_slave_config(as->dma.chan_tx, slave_config)) {
+	if (dmaengine_slave_config(master->dma_tx, slave_config)) {
 		dev_err(&as->pdev->dev,
 			"failed to configure tx dma channel\n");
 		err = -EINVAL;
@@ -506,7 +500,7 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 	 * enabled) or not.
 	 */
 	slave_config->direction = DMA_DEV_TO_MEM;
-	if (dmaengine_slave_config(as->dma.chan_rx, slave_config)) {
+	if (dmaengine_slave_config(master->dma_rx, slave_config)) {
 		dev_err(&as->pdev->dev,
 			"failed to configure rx dma channel\n");
 		err = -EINVAL;
@@ -515,7 +509,8 @@ static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 	return err;
 }
 
-static int atmel_spi_configure_dma(struct atmel_spi *as)
+static int atmel_spi_configure_dma(struct spi_master *master,
+				   struct atmel_spi *as)
 {
 	struct dma_slave_config	slave_config;
 	struct device *dev = &as->pdev->dev;
@@ -525,26 +520,26 @@ static int atmel_spi_configure_dma(struct atmel_spi *as)
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 
-	as->dma.chan_tx = dma_request_slave_channel_reason(dev, "tx");
-	if (IS_ERR(as->dma.chan_tx)) {
-		err = PTR_ERR(as->dma.chan_tx);
+	master->dma_tx = dma_request_slave_channel_reason(dev, "tx");
+	if (IS_ERR(master->dma_tx)) {
+		err = PTR_ERR(master->dma_tx);
 		if (err == -EPROBE_DEFER) {
 			dev_warn(dev, "no DMA channel available at the moment\n");
-			return err;
+			goto error_clear;
 		}
 		dev_err(dev,
 			"DMA TX channel not available, SPI unable to use DMA\n");
 		err = -EBUSY;
-		goto error;
+		goto error_clear;
 	}
 
 	/*
 	 * No reason to check EPROBE_DEFER here since we have already requested
 	 * tx channel. If it fails here, it's for another reason.
 	 */
-	as->dma.chan_rx = dma_request_slave_channel(dev, "rx");
+	master->dma_rx = dma_request_slave_channel(dev, "rx");
 
-	if (!as->dma.chan_rx) {
+	if (!master->dma_rx) {
 		dev_err(dev,
 			"DMA RX channel not available, SPI unable to use DMA\n");
 		err = -EBUSY;
@@ -557,31 +552,38 @@ static int atmel_spi_configure_dma(struct atmel_spi *as)
 
 	dev_info(&as->pdev->dev,
 			"Using %s (tx) and %s (rx) for DMA transfers\n",
-			dma_chan_name(as->dma.chan_tx),
-			dma_chan_name(as->dma.chan_rx));
+			dma_chan_name(master->dma_tx),
+			dma_chan_name(master->dma_rx));
+
 	return 0;
 error:
-	if (as->dma.chan_rx)
-		dma_release_channel(as->dma.chan_rx);
-	if (!IS_ERR(as->dma.chan_tx))
-		dma_release_channel(as->dma.chan_tx);
+	if (master->dma_rx)
+		dma_release_channel(master->dma_rx);
+	if (!IS_ERR(master->dma_tx))
+		dma_release_channel(master->dma_tx);
+error_clear:
+	master->dma_tx = master->dma_rx = NULL;
 	return err;
 }
 
-static void atmel_spi_stop_dma(struct atmel_spi *as)
+static void atmel_spi_stop_dma(struct spi_master *master)
 {
-	if (as->dma.chan_rx)
-		dmaengine_terminate_all(as->dma.chan_rx);
-	if (as->dma.chan_tx)
-		dmaengine_terminate_all(as->dma.chan_tx);
+	if (master->dma_rx)
+		dmaengine_terminate_all(master->dma_rx);
+	if (master->dma_tx)
+		dmaengine_terminate_all(master->dma_tx);
 }
 
-static void atmel_spi_release_dma(struct atmel_spi *as)
+static void atmel_spi_release_dma(struct spi_master *master)
 {
-	if (as->dma.chan_rx)
-		dma_release_channel(as->dma.chan_rx);
-	if (as->dma.chan_tx)
-		dma_release_channel(as->dma.chan_tx);
+	if (master->dma_rx) {
+		dma_release_channel(master->dma_rx);
+		master->dma_rx = NULL;
+	}
+	if (master->dma_tx) {
+		dma_release_channel(master->dma_tx);
+		master->dma_tx = NULL;
+	}
 }
 
 /* This function is called by the DMA driver from tasklet context */
@@ -717,8 +719,8 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 				u32 *plen)
 {
 	struct atmel_spi	*as = spi_master_get_devdata(master);
-	struct dma_chan		*rxchan = as->dma.chan_rx;
-	struct dma_chan		*txchan = as->dma.chan_tx;
+	struct dma_chan		*rxchan = master->dma_rx;
+	struct dma_chan		*txchan = master->dma_tx;
 	struct dma_async_tx_descriptor *rxdesc;
 	struct dma_async_tx_descriptor *txdesc;
 	struct dma_slave_config	slave_config;
@@ -782,7 +784,7 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 
 err_dma:
 	spi_writel(as, IDR, SPI_BIT(OVRES));
-	atmel_spi_stop_dma(as);
+	atmel_spi_stop_dma(master);
 err_exit:
 	atmel_spi_lock(as);
 	return -ENOMEM;
@@ -1310,7 +1312,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 			spi_readl(as, SR);
 
 		} else if (atmel_spi_use_dma(as, xfer)) {
-			atmel_spi_stop_dma(as);
+			atmel_spi_stop_dma(master);
 		}
 
 		if (!msg->is_dma_mapped
@@ -1539,10 +1541,8 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	as->use_dma = false;
 	as->use_pdc = false;
 	if (as->caps.has_dma_support) {
-		ret = atmel_spi_configure_dma(as);
+		ret = atmel_spi_configure_dma(master, as);
 		if (ret == 0) {
-			master->dma_tx = as->dma.chan_tx;
-			master->dma_rx = as->dma.chan_rx;
 			as->use_dma = true;
 		} else if (ret == -EPROBE_DEFER) {
 			return ret;
@@ -1608,7 +1608,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	pm_runtime_set_suspended(&pdev->dev);
 
 	if (as->use_dma)
-		atmel_spi_release_dma(as);
+		atmel_spi_release_dma(master);
 
 	spi_writel(as, CR, SPI_BIT(SWRST));
 	spi_writel(as, CR, SPI_BIT(SWRST)); /* AT91SAM9263 Rev B workaround */
@@ -1630,8 +1630,8 @@ static int atmel_spi_remove(struct platform_device *pdev)
 	/* reset the hardware and block queue progress */
 	spin_lock_irq(&as->lock);
 	if (as->use_dma) {
-		atmel_spi_stop_dma(as);
-		atmel_spi_release_dma(as);
+		atmel_spi_stop_dma(master);
+		atmel_spi_release_dma(master);
 	}
 
 	spi_writel(as, CR, SPI_BIT(SWRST));
-- 
2.10.2

Applied "spi: atmel: trivial: remove unused fields in DMA structure" to the spi tree

[Mark Brown]

The patch

   spi: atmel: trivial: remove unused fields in DMA structure

has been applied to the spi tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

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

>From d5fab59cab1875b42b93f53da248cac90046547d Mon Sep 17 00:00:00 2001
From: Nicolas Ferre <nicolas.ferre@atmel.com>
Date: Thu, 24 Nov 2016 12:25:00 +0100
Subject: [PATCH] spi: atmel: trivial: remove unused fields in DMA structure

The atmel_spi_dma structure was cluttered with unused fields relative
to older DMA channel selection API. Remove them.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/spi-atmel.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 7e03e221d307..1a21bc6f7d7a 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -268,10 +268,6 @@
 struct atmel_spi_dma {
 	struct dma_chan			*chan_rx;
 	struct dma_chan			*chan_tx;
-	struct dma_async_tx_descriptor	*data_desc_rx;
-	struct dma_async_tx_descriptor	*data_desc_tx;
-
-	struct at_dma_slave	dma_slave;
 };
 
 struct atmel_spi_caps {
-- 
2.10.2

Applied "spi: atmel: Use SPI core DMA mapping framework" to the spi tree

[Mark Brown]

The patch

   spi: atmel: Use SPI core DMA mapping framework

has been applied to the spi tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

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

>From 04242ca4e8917999ac2bbc3d2b10409661f60272 Mon Sep 17 00:00:00 2001
From: Cyrille Pitchen <cyrille.pitchen@atmel.com>
Date: Thu, 24 Nov 2016 12:24:59 +0100
Subject: [PATCH] spi: atmel: Use SPI core DMA mapping framework

Use the SPI core DMA mapping framework instead of our own
in case of DMA support. PDC support is not converted to this
framework.

The driver is now able to transfer a complete sg list through DMA.
This eventually fix an issue with vmalloc'ed DMA memory that is
provided for example by UBI/UBIFS layers.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com>
[nicolas.ferre@atmel.com: restrict the use to non-PDC DMA]
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
 drivers/spi/spi-atmel.c | 57 ++++++++++++++++++++++---------------------------
 1 file changed, 25 insertions(+), 32 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 8f20d4f75e4a..7e03e221d307 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -268,8 +268,6 @@
 struct atmel_spi_dma {
 	struct dma_chan			*chan_rx;
 	struct dma_chan			*chan_tx;
-	struct scatterlist		sgrx;
-	struct scatterlist		sgtx;
 	struct dma_async_tx_descriptor	*data_desc_rx;
 	struct dma_async_tx_descriptor	*data_desc_tx;
 
@@ -453,6 +451,15 @@ static inline bool atmel_spi_use_dma(struct atmel_spi *as,
 	return as->use_dma && xfer->len >= DMA_MIN_BYTES;
 }
 
+static bool atmel_spi_can_dma(struct spi_master *master,
+			      struct spi_device *spi,
+			      struct spi_transfer *xfer)
+{
+	struct atmel_spi *as = spi_master_get_devdata(master);
+
+	return atmel_spi_use_dma(as, xfer);
+}
+
 static int atmel_spi_dma_slave_config(struct atmel_spi *as,
 				struct dma_slave_config *slave_config,
 				u8 bits_per_word)
@@ -720,7 +727,6 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 	struct dma_async_tx_descriptor *txdesc;
 	struct dma_slave_config	slave_config;
 	dma_cookie_t		cookie;
-	u32	len = *plen;
 
 	dev_vdbg(master->dev.parent, "atmel_spi_next_xfer_dma_submit\n");
 
@@ -731,34 +737,22 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 	/* release lock for DMA operations */
 	atmel_spi_unlock(as);
 
-	/* prepare the RX dma transfer */
-	sg_init_table(&as->dma.sgrx, 1);
-	as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
-
-	/* prepare the TX dma transfer */
-	sg_init_table(&as->dma.sgtx, 1);
-	as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
-
-	if (len > master->max_dma_len)
-		len = master->max_dma_len;
-
-	sg_dma_len(&as->dma.sgtx) = len;
-	sg_dma_len(&as->dma.sgrx) = len;
-
-	*plen = len;
+	*plen = xfer->len;
 
 	if (atmel_spi_dma_slave_config(as, &slave_config,
 				       xfer->bits_per_word))
 		goto err_exit;
 
 	/* Send both scatterlists */
-	rxdesc = dmaengine_prep_slave_sg(rxchan, &as->dma.sgrx, 1,
+	rxdesc = dmaengine_prep_slave_sg(rxchan,
+					 xfer->rx_sg.sgl, xfer->rx_sg.nents,
 					 DMA_FROM_DEVICE,
 					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!rxdesc)
 		goto err_dma;
 
-	txdesc = dmaengine_prep_slave_sg(txchan, &as->dma.sgtx, 1,
+	txdesc = dmaengine_prep_slave_sg(txchan,
+					 xfer->tx_sg.sgl, xfer->tx_sg.nents,
 					 DMA_TO_DEVICE,
 					 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 	if (!txdesc)
@@ -804,15 +798,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master,
 				dma_addr_t *rx_dma,
 				u32 *plen)
 {
-	struct atmel_spi	*as = spi_master_get_devdata(master);
-	u32			len = *plen;
-
 	*rx_dma = xfer->rx_dma + xfer->len - *plen;
 	*tx_dma = xfer->tx_dma + xfer->len - *plen;
-	if (len > master->max_dma_len)
-		len = master->max_dma_len;
-
-	*plen = len;
+	if (*plen > master->max_dma_len)
+		*plen = master->max_dma_len;
 }
 
 static int atmel_spi_set_xfer_speed(struct atmel_spi *as,
@@ -1252,7 +1241,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 	 * better fault reporting.
 	 */
 	if ((!msg->is_dma_mapped)
-		&& (atmel_spi_use_dma(as, xfer)	|| as->use_pdc)) {
+		&& as->use_pdc) {
 		if (atmel_spi_dma_map_xfer(as, xfer) < 0)
 			return -ENOMEM;
 	}
@@ -1329,7 +1318,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 		}
 
 		if (!msg->is_dma_mapped
-			&& (atmel_spi_use_dma(as, xfer) || as->use_pdc))
+			&& as->use_pdc)
 			atmel_spi_dma_unmap_xfer(master, xfer);
 
 		return 0;
@@ -1340,7 +1329,7 @@ static int atmel_spi_one_transfer(struct spi_master *master,
 	}
 
 	if (!msg->is_dma_mapped
-		&& (atmel_spi_use_dma(as, xfer) || as->use_pdc))
+		&& as->use_pdc)
 		atmel_spi_dma_unmap_xfer(master, xfer);
 
 	if (xfer->delay_usecs)
@@ -1518,6 +1507,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	master->cleanup = atmel_spi_cleanup;
 	master->auto_runtime_pm = true;
 	master->max_dma_len = SPI_MAX_DMA_XFER;
+	master->can_dma = atmel_spi_can_dma;
 	platform_set_drvdata(pdev, master);
 
 	as = spi_master_get_devdata(master);
@@ -1554,10 +1544,13 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	as->use_pdc = false;
 	if (as->caps.has_dma_support) {
 		ret = atmel_spi_configure_dma(as);
-		if (ret == 0)
+		if (ret == 0) {
+			master->dma_tx = as->dma.chan_tx;
+			master->dma_rx = as->dma.chan_rx;
 			as->use_dma = true;
-		else if (ret == -EPROBE_DEFER)
+		} else if (ret == -EPROBE_DEFER) {
 			return ret;
+		}
 	} else {
 		as->use_pdc = true;
 	}
-- 
2.10.2

Applied "spi: atmel: Use core SPI_MASTER_MUST_[RT]X handling" to the spi tree

[Mark Brown]

The patch

   spi: atmel: Use core SPI_MASTER_MUST_[RT]X handling

has been applied to the spi tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

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

>From 7910d9af000acc155745e44be55a5d0dc9e26ce7 Mon Sep 17 00:00:00 2001
From: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
Date: Thu, 24 Nov 2016 12:24:58 +0100
Subject: [PATCH] spi: atmel: Use core SPI_MASTER_MUST_[RT]X handling

We need both RX and TX data for each transfer in any case (PIO, PDC, DMA).
So convert the driver to the core dummy buffer handling with the
SPI_MASTER_MUST_RX/SPI_MASTER_MUST_TX infrastructure.

This move changes the maximum PDC/DMA buffer handling to 65535 bytes
instead of a single page and sets master->max_dma_len to this value.

All dummy buffer management is removed from the driver.

Signed-off-by: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
 drivers/spi/spi-atmel.c | 131 +++++++++++++-----------------------------------
 1 file changed, 35 insertions(+), 96 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index a9ae1836e1e2..8f20d4f75e4a 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -303,10 +303,6 @@ struct atmel_spi {
 
 	struct completion	xfer_completion;
 
-	/* scratch buffer */
-	void			*buffer;
-	dma_addr_t		buffer_dma;
-
 	struct atmel_spi_caps	caps;
 
 	bool			use_dma;
@@ -327,7 +323,7 @@ struct atmel_spi_device {
 	u32			csr;
 };
 
-#define BUFFER_SIZE		PAGE_SIZE
+#define SPI_MAX_DMA_XFER	65535 /* true for both PDC and DMA */
 #define INVALID_DMA_ADDRESS	0xffffffff
 
 /*
@@ -612,14 +608,10 @@ static void atmel_spi_next_xfer_single(struct spi_master *master,
 		cpu_relax();
 	}
 
-	if (xfer->tx_buf) {
-		if (xfer->bits_per_word > 8)
-			spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos));
-		else
-			spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos));
-	} else {
-		spi_writel(as, TDR, 0);
-	}
+	if (xfer->bits_per_word > 8)
+		spi_writel(as, TDR, *(u16 *)(xfer->tx_buf + xfer_pos));
+	else
+		spi_writel(as, TDR, *(u8 *)(xfer->tx_buf + xfer_pos));
 
 	dev_dbg(master->dev.parent,
 		"  start pio xfer %p: len %u tx %p rx %p bitpw %d\n",
@@ -666,17 +658,12 @@ static void atmel_spi_next_xfer_fifo(struct spi_master *master,
 
 	/* Fill TX FIFO */
 	while (num_data >= 2) {
-		if (xfer->tx_buf) {
-			if (xfer->bits_per_word > 8) {
-				td0 = *words++;
-				td1 = *words++;
-			} else {
-				td0 = *bytes++;
-				td1 = *bytes++;
-			}
+		if (xfer->bits_per_word > 8) {
+			td0 = *words++;
+			td1 = *words++;
 		} else {
-			td0 = 0;
-			td1 = 0;
+			td0 = *bytes++;
+			td1 = *bytes++;
 		}
 
 		spi_writel(as, TDR, (td1 << 16) | td0);
@@ -684,14 +671,10 @@ static void atmel_spi_next_xfer_fifo(struct spi_master *master,
 	}
 
 	if (num_data) {
-		if (xfer->tx_buf) {
-			if (xfer->bits_per_word > 8)
-				td0 = *words++;
-			else
-				td0 = *bytes++;
-		} else {
-			td0 = 0;
-		}
+		if (xfer->bits_per_word > 8)
+			td0 = *words++;
+		else
+			td0 = *bytes++;
 
 		spi_writew(as, TDR, td0);
 		num_data--;
@@ -750,24 +733,14 @@ static int atmel_spi_next_xfer_dma_submit(struct spi_master *master,
 
 	/* prepare the RX dma transfer */
 	sg_init_table(&as->dma.sgrx, 1);
-	if (xfer->rx_buf) {
-		as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
-	} else {
-		as->dma.sgrx.dma_address = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-	}
+	as->dma.sgrx.dma_address = xfer->rx_dma + xfer->len - *plen;
 
 	/* prepare the TX dma transfer */
 	sg_init_table(&as->dma.sgtx, 1);
-	if (xfer->tx_buf) {
-		as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
-	} else {
-		as->dma.sgtx.dma_address = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-		memset(as->buffer, 0, len);
-	}
+	as->dma.sgtx.dma_address = xfer->tx_dma + xfer->len - *plen;
+
+	if (len > master->max_dma_len)
+		len = master->max_dma_len;
 
 	sg_dma_len(&as->dma.sgtx) = len;
 	sg_dma_len(&as->dma.sgrx) = len;
@@ -834,25 +807,10 @@ static void atmel_spi_next_xfer_data(struct spi_master *master,
 	struct atmel_spi	*as = spi_master_get_devdata(master);
 	u32			len = *plen;
 
-	/* use scratch buffer only when rx or tx data is unspecified */
-	if (xfer->rx_buf)
-		*rx_dma = xfer->rx_dma + xfer->len - *plen;
-	else {
-		*rx_dma = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-	}
-
-	if (xfer->tx_buf)
-		*tx_dma = xfer->tx_dma + xfer->len - *plen;
-	else {
-		*tx_dma = as->buffer_dma;
-		if (len > BUFFER_SIZE)
-			len = BUFFER_SIZE;
-		memset(as->buffer, 0, len);
-		dma_sync_single_for_device(&as->pdev->dev,
-				as->buffer_dma, len, DMA_TO_DEVICE);
-	}
+	*rx_dma = xfer->rx_dma + xfer->len - *plen;
+	*tx_dma = xfer->tx_dma + xfer->len - *plen;
+	if (len > master->max_dma_len)
+		len = master->max_dma_len;
 
 	*plen = len;
 }
@@ -1026,16 +984,12 @@ atmel_spi_pump_single_data(struct atmel_spi *as, struct spi_transfer *xfer)
 	u16		*rxp16;
 	unsigned long	xfer_pos = xfer->len - as->current_remaining_bytes;
 
-	if (xfer->rx_buf) {
-		if (xfer->bits_per_word > 8) {
-			rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos);
-			*rxp16 = spi_readl(as, RDR);
-		} else {
-			rxp = ((u8 *)xfer->rx_buf) + xfer_pos;
-			*rxp = spi_readl(as, RDR);
-		}
+	if (xfer->bits_per_word > 8) {
+		rxp16 = (u16 *)(((u8 *)xfer->rx_buf) + xfer_pos);
+		*rxp16 = spi_readl(as, RDR);
 	} else {
-		spi_readl(as, RDR);
+		rxp = ((u8 *)xfer->rx_buf) + xfer_pos;
+		*rxp = spi_readl(as, RDR);
 	}
 	if (xfer->bits_per_word > 8) {
 		if (as->current_remaining_bytes > 2)
@@ -1074,12 +1028,10 @@ atmel_spi_pump_fifo_data(struct atmel_spi *as, struct spi_transfer *xfer)
 	/* Read data */
 	while (num_data) {
 		rd = spi_readl(as, RDR);
-		if (xfer->rx_buf) {
-			if (xfer->bits_per_word > 8)
-				*words++ = rd;
-			else
-				*bytes++ = rd;
-		}
+		if (xfer->bits_per_word > 8)
+			*words++ = rd;
+		else
+			*bytes++ = rd;
 		num_data--;
 	}
 }
@@ -1561,29 +1513,22 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	master->bus_num = pdev->id;
 	master->num_chipselect = master->dev.of_node ? 0 : 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->cleanup = atmel_spi_cleanup;
 	master->auto_runtime_pm = true;
+	master->max_dma_len = SPI_MAX_DMA_XFER;
 	platform_set_drvdata(pdev, master);
 
 	as = spi_master_get_devdata(master);
 
-	/*
-	 * Scratch buffer is used for throwaway rx and tx data.
-	 * It's coherent to minimize dcache pollution.
-	 */
-	as->buffer = dma_alloc_coherent(&pdev->dev, BUFFER_SIZE,
-					&as->buffer_dma, GFP_KERNEL);
-	if (!as->buffer)
-		goto out_free;
-
 	spin_lock_init(&as->lock);
 
 	as->pdev = pdev;
 	as->regs = devm_ioremap_resource(&pdev->dev, regs);
 	if (IS_ERR(as->regs)) {
 		ret = PTR_ERR(as->regs);
-		goto out_free_buffer;
+		goto out_unmap_regs;
 	}
 	as->phybase = regs->start;
 	as->irq = irq;
@@ -1681,9 +1626,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	clk_disable_unprepare(clk);
 out_free_irq:
 out_unmap_regs:
-out_free_buffer:
-	dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
-			as->buffer_dma);
 out_free:
 	spi_master_put(master);
 	return ret;
@@ -1708,9 +1650,6 @@ static int atmel_spi_remove(struct platform_device *pdev)
 	spi_readl(as, SR);
 	spin_unlock_irq(&as->lock);
 
-	dma_free_coherent(&pdev->dev, BUFFER_SIZE, as->buffer,
-			as->buffer_dma);
-
 	clk_disable_unprepare(as->clk);
 
 	pm_runtime_put_noidle(&pdev->dev);
-- 
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Applied "spi: atmel: trivial: move info banner to latest probe action" to the spi tree

[Mark Brown]

The patch

   spi: atmel: trivial: move info banner to latest probe action

has been applied to the spi tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

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

>From ce24a513fb142e855b4aa77f91334c2f203c0d99 Mon Sep 17 00:00:00 2001
From: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
Date: Thu, 24 Nov 2016 12:24:57 +0100
Subject: [PATCH] spi: atmel: trivial: move info banner to latest probe action

The info banner is here to tell that everything went well, so place
it at the very end of the probe function.

Signed-off-by: Nicolas Ferre <nicolas.ferre-AIFe0yeh4nAAvxtiuMwx3w@public.gmane.org>
Signed-off-by: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
 drivers/spi/spi-atmel.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index b2931493cab2..a9ae1836e1e2 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -1654,10 +1654,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
 		spi_writel(as, CR, SPI_BIT(FIFOEN));
 	}
 
-	/* go! */
-	dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n",
-			(unsigned long)regs->start, irq);
-
 	pm_runtime_set_autosuspend_delay(&pdev->dev, AUTOSUSPEND_TIMEOUT);
 	pm_runtime_use_autosuspend(&pdev->dev);
 	pm_runtime_set_active(&pdev->dev);
@@ -1667,6 +1663,10 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	if (ret)
 		goto out_free_dma;
 
+	/* go! */
+	dev_info(&pdev->dev, "Atmel SPI Controller at 0x%08lx (irq %d)\n",
+			(unsigned long)regs->start, irq);
+
 	return 0;
 
 out_free_dma:
-- 
2.10.2

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html