* [PATCH v2 1/2] spi: rspi: Handle dmaengine_prep_slave_sg() failures gracefully
@ 2014-07-11 16:01 ` Geert Uytterhoeven
0 siblings, 0 replies; 6+ messages in thread
From: Geert Uytterhoeven @ 2014-07-11 16:01 UTC (permalink / raw)
To: Mark Brown
Cc: Laurent Pinchart, linux-spi, dmaengine, linux-sh, linux-kernel,
Geert Uytterhoeven
As typically a shmobile SoC has less DMA channels than devices that can use
DMA, we may want to prioritize access to the DMA channels in the future.
This means that dmaengine_prep_slave_sg() may start failing arbitrarily.
Handle dmaengine_prep_slave_sg() failures gracefully by falling back to
PIO.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
v2:
- Add Acked-by
---
drivers/spi/spi-rspi.c | 30 ++++++++++++++++++++++--------
1 file changed, 22 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 38fd938d6360..c850dfdfa9e3 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -477,7 +477,7 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
tx->sgl, tx->nents, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx)
- return -EIO;
+ goto no_dma;
irq_mask |= SPCR_SPTIE;
}
@@ -486,7 +486,7 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
rx->sgl, rx->nents, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
- return -EIO;
+ goto no_dma;
irq_mask |= SPCR_SPRIE;
}
@@ -540,6 +540,12 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
enable_irq(rspi->rx_irq);
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;
}
static void rspi_receive_init(const struct rspi_data *rspi)
@@ -593,8 +599,10 @@ 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);
@@ -648,8 +656,11 @@ 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)
@@ -663,8 +674,11 @@ 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);
}
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v2 1/2] spi: rspi: Handle dmaengine_prep_slave_sg() failures gracefully
@ 2014-07-11 16:01 ` Geert Uytterhoeven
0 siblings, 0 replies; 6+ messages in thread
From: Geert Uytterhoeven @ 2014-07-11 16:01 UTC (permalink / raw)
To: Mark Brown
Cc: Laurent Pinchart, linux-spi, dmaengine, linux-sh, linux-kernel,
Geert Uytterhoeven
As typically a shmobile SoC has less DMA channels than devices that can use
DMA, we may want to prioritize access to the DMA channels in the future.
This means that dmaengine_prep_slave_sg() may start failing arbitrarily.
Handle dmaengine_prep_slave_sg() failures gracefully by falling back to
PIO.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
v2:
- Add Acked-by
---
drivers/spi/spi-rspi.c | 30 ++++++++++++++++++++++--------
1 file changed, 22 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/spi-rspi.c b/drivers/spi/spi-rspi.c
index 38fd938d6360..c850dfdfa9e3 100644
--- a/drivers/spi/spi-rspi.c
+++ b/drivers/spi/spi-rspi.c
@@ -477,7 +477,7 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
tx->sgl, tx->nents, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx)
- return -EIO;
+ goto no_dma;
irq_mask |= SPCR_SPTIE;
}
@@ -486,7 +486,7 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
rx->sgl, rx->nents, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
- return -EIO;
+ goto no_dma;
irq_mask |= SPCR_SPRIE;
}
@@ -540,6 +540,12 @@ static int rspi_dma_transfer(struct rspi_data *rspi, struct sg_table *tx,
enable_irq(rspi->rx_irq);
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;
}
static void rspi_receive_init(const struct rspi_data *rspi)
@@ -593,8 +599,10 @@ 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);
@@ -648,8 +656,11 @@ 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)
@@ -663,8 +674,11 @@ 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);
}
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v2 2/2] spi: sh-msiof: Handle dmaengine_prep_slave_single() failures gracefully
2014-07-11 16:01 ` Geert Uytterhoeven
@ 2014-07-11 16:01 ` Geert Uytterhoeven
-1 siblings, 0 replies; 6+ messages in thread
From: Geert Uytterhoeven @ 2014-07-11 16:01 UTC (permalink / raw)
To: Mark Brown
Cc: Laurent Pinchart, linux-spi, dmaengine, linux-sh, linux-kernel,
Geert Uytterhoeven
As typically a shmobile SoC has less DMA channels than devices that can use
DMA, we may want to prioritize access to the DMA channels in the future.
This means that dmaengine_prep_slave_single() may start failing
arbitrarily.
Handle dmaengine_prep_slave_single() failures gracefully by falling back to
PIO. This requires moving DMA-specific configuration of the MSIOF device
after the call(s) to dmaengine_prep_slave_single().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
v2:
- Add Acked-by
---
drivers/spi/spi-sh-msiof.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 6f449b24704a..2a4354dcd661 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -636,12 +636,6 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
dma_cookie_t cookie;
int ret;
- /* 1 stage FIFO watermarks for DMA */
- sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
-
- /* setup msiof transfer mode registers (32-bit words) */
- sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
-
if (tx) {
ier_bits |= IER_TDREQE | IER_TDMAE;
dma_sync_single_for_device(p->master->dma_tx->device->dev,
@@ -650,7 +644,7 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
p->tx_dma_addr, len, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx)
- return -EIO;
+ return -EAGAIN;
}
if (rx) {
@@ -659,8 +653,15 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
p->rx_dma_addr, len, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
- return -EIO;
+ return -EAGAIN;
}
+
+ /* 1 stage FIFO watermarks for DMA */
+ sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
+
+ /* setup msiof transfer mode registers (32-bit words) */
+ sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
+
sh_msiof_write(p, IER, ier_bits);
reinit_completion(&p->done);
@@ -823,6 +824,12 @@ static int sh_msiof_transfer_one(struct spi_master *master,
copy32(p->tx_dma_page, tx_buf, l / 4);
ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
+ if (ret = -EAGAIN) {
+ pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
+ dev_driver_string(&p->pdev->dev),
+ dev_name(&p->pdev->dev));
+ break;
+ }
if (ret)
return ret;
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v2 2/2] spi: sh-msiof: Handle dmaengine_prep_slave_single() failures gracefully
@ 2014-07-11 16:01 ` Geert Uytterhoeven
0 siblings, 0 replies; 6+ messages in thread
From: Geert Uytterhoeven @ 2014-07-11 16:01 UTC (permalink / raw)
To: Mark Brown
Cc: Laurent Pinchart, linux-spi, dmaengine, linux-sh, linux-kernel,
Geert Uytterhoeven
As typically a shmobile SoC has less DMA channels than devices that can use
DMA, we may want to prioritize access to the DMA channels in the future.
This means that dmaengine_prep_slave_single() may start failing
arbitrarily.
Handle dmaengine_prep_slave_single() failures gracefully by falling back to
PIO. This requires moving DMA-specific configuration of the MSIOF device
after the call(s) to dmaengine_prep_slave_single().
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
---
v2:
- Add Acked-by
---
drivers/spi/spi-sh-msiof.c | 23 +++++++++++++++--------
1 file changed, 15 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 6f449b24704a..2a4354dcd661 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -636,12 +636,6 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
dma_cookie_t cookie;
int ret;
- /* 1 stage FIFO watermarks for DMA */
- sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
-
- /* setup msiof transfer mode registers (32-bit words) */
- sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
-
if (tx) {
ier_bits |= IER_TDREQE | IER_TDMAE;
dma_sync_single_for_device(p->master->dma_tx->device->dev,
@@ -650,7 +644,7 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
p->tx_dma_addr, len, DMA_TO_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_tx)
- return -EIO;
+ return -EAGAIN;
}
if (rx) {
@@ -659,8 +653,15 @@ static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
p->rx_dma_addr, len, DMA_FROM_DEVICE,
DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
if (!desc_rx)
- return -EIO;
+ return -EAGAIN;
}
+
+ /* 1 stage FIFO watermarks for DMA */
+ sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
+
+ /* setup msiof transfer mode registers (32-bit words) */
+ sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
+
sh_msiof_write(p, IER, ier_bits);
reinit_completion(&p->done);
@@ -823,6 +824,12 @@ static int sh_msiof_transfer_one(struct spi_master *master,
copy32(p->tx_dma_page, tx_buf, l / 4);
ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
+ if (ret == -EAGAIN) {
+ pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
+ dev_driver_string(&p->pdev->dev),
+ dev_name(&p->pdev->dev));
+ break;
+ }
if (ret)
return ret;
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v2 1/2] spi: rspi: Handle dmaengine_prep_slave_sg() failures gracefully
2014-07-11 16:01 ` Geert Uytterhoeven
@ 2014-07-14 18:21 ` Mark Brown
-1 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2014-07-14 18:21 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Laurent Pinchart, linux-spi, dmaengine, linux-sh, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 319 bytes --]
On Fri, Jul 11, 2014 at 06:01:16PM +0200, Geert Uytterhoeven wrote:
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> v2:
> - Add Acked-by
Please don't ever resend things to add Acked-by - this just adds to
noise and mail volume.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v2 1/2] spi: rspi: Handle dmaengine_prep_slave_sg() failures gracefully
@ 2014-07-14 18:21 ` Mark Brown
0 siblings, 0 replies; 6+ messages in thread
From: Mark Brown @ 2014-07-14 18:21 UTC (permalink / raw)
To: Geert Uytterhoeven
Cc: Laurent Pinchart, linux-spi, dmaengine, linux-sh, linux-kernel
[-- Attachment #1: Type: text/plain, Size: 319 bytes --]
On Fri, Jul 11, 2014 at 06:01:16PM +0200, Geert Uytterhoeven wrote:
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> v2:
> - Add Acked-by
Please don't ever resend things to add Acked-by - this just adds to
noise and mail volume.
[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2014-07-14 18:22 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-07-11 16:01 [PATCH v2 1/2] spi: rspi: Handle dmaengine_prep_slave_sg() failures gracefully Geert Uytterhoeven
2014-07-11 16:01 ` Geert Uytterhoeven
2014-07-11 16:01 ` [PATCH v2 2/2] spi: sh-msiof: Handle dmaengine_prep_slave_single() " Geert Uytterhoeven
2014-07-11 16:01 ` Geert Uytterhoeven
2014-07-14 18:21 ` [PATCH v2 1/2] spi: rspi: Handle dmaengine_prep_slave_sg() " Mark Brown
2014-07-14 18:21 ` Mark Brown
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