[PATCH v2 0/2] add edma src ID check at request channel

[PATCH v2 0/2] add edma src ID check at request channel

[Joy Zou]

For the details, please check the patch commit log.

Changes in v2:
1. modify the dev_err() log description.
2. add review tag.

Joy Zou (2):
  dmaengine: fsl-edma: change to guard(mutex) within fsl_edma3_xlate()
  dmaengine: fsl-edma: add edma src ID check at request channel

 drivers/dma/fsl-edma-main.c | 27 +++++++++++++++++++++++----
 1 file changed, 23 insertions(+), 4 deletions(-)

-- 
2.37.1

[PATCH v2 1/2] dmaengine: fsl-edma: change to guard(mutex) within fsl_edma3_xlate()

[Joy Zou]

Introduce a scope guard to automatically unlock the mutex within
fsl_edma3_xlate() to simplify the code.

Prepare to add source ID checks in the future.

Signed-off-by: Joy Zou <joy.zou@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/fsl-edma-main.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
index c66185c5a199..d4f29ece69f5 100644
--- a/drivers/dma/fsl-edma-main.c
+++ b/drivers/dma/fsl-edma-main.c
@@ -153,7 +153,7 @@ static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
 
 	b_chmux = !!(fsl_edma->drvdata->flags & FSL_EDMA_DRV_HAS_CHMUX);
 
-	mutex_lock(&fsl_edma->fsl_edma_mutex);
+	guard(mutex)(&fsl_edma->fsl_edma_mutex);
 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels,
 					device_node) {
 
@@ -177,18 +177,15 @@ static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
 		if (!b_chmux && i == dma_spec->args[0]) {
 			chan = dma_get_slave_channel(chan);
 			chan->device->privatecnt++;
-			mutex_unlock(&fsl_edma->fsl_edma_mutex);
 			return chan;
 		} else if (b_chmux && !fsl_chan->srcid) {
 			/* if controller support channel mux, choose a free channel */
 			chan = dma_get_slave_channel(chan);
 			chan->device->privatecnt++;
 			fsl_chan->srcid = dma_spec->args[0];
-			mutex_unlock(&fsl_edma->fsl_edma_mutex);
 			return chan;
 		}
 	}
-	mutex_unlock(&fsl_edma->fsl_edma_mutex);
 	return NULL;
 }
 
-- 
2.37.1

[PATCH v2 2/2] dmaengine: fsl-edma: add edma src ID check at request channel

[Joy Zou]

Check src ID to detect misuse of same src ID for multiple DMA channels.

Signed-off-by: Joy Zou <joy.zou@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
---
 drivers/dma/fsl-edma-main.c | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/dma/fsl-edma-main.c b/drivers/dma/fsl-edma-main.c
index d4f29ece69f5..f9f1eda79254 100644
--- a/drivers/dma/fsl-edma-main.c
+++ b/drivers/dma/fsl-edma-main.c
@@ -100,6 +100,22 @@ static irqreturn_t fsl_edma_irq_handler(int irq, void *dev_id)
 	return fsl_edma_err_handler(irq, dev_id);
 }
 
+static bool fsl_edma_srcid_in_use(struct fsl_edma_engine *fsl_edma, u32 srcid)
+{
+	struct fsl_edma_chan *fsl_chan;
+	int i;
+
+	for (i = 0; i < fsl_edma->n_chans; i++) {
+		fsl_chan = &fsl_edma->chans[i];
+
+		if (fsl_chan->srcid && srcid == fsl_chan->srcid) {
+			dev_err(&fsl_chan->pdev->dev, "The srcid is in use, can't use!");
+			return true;
+		}
+	}
+	return false;
+}
+
 static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
 		struct of_dma *ofdma)
 {
@@ -117,6 +133,10 @@ static struct dma_chan *fsl_edma_xlate(struct of_phandle_args *dma_spec,
 	list_for_each_entry_safe(chan, _chan, &fsl_edma->dma_dev.channels, device_node) {
 		if (chan->client_count)
 			continue;
+
+		if (fsl_edma_srcid_in_use(fsl_edma, dma_spec->args[1]))
+			return NULL;
+
 		if ((chan->chan_id / chans_per_mux) == dma_spec->args[0]) {
 			chan = dma_get_slave_channel(chan);
 			if (chan) {
@@ -161,6 +181,8 @@ static struct dma_chan *fsl_edma3_xlate(struct of_phandle_args *dma_spec,
 			continue;
 
 		fsl_chan = to_fsl_edma_chan(chan);
+		if (fsl_edma_srcid_in_use(fsl_edma, dma_spec->args[0]))
+			return NULL;
 		i = fsl_chan - fsl_edma->chans;
 
 		fsl_chan->priority = dma_spec->args[1];
-- 
2.37.1

Re: [PATCH v2 0/2] add edma src ID check at request channel

[Vinod Koul]

On Mon, 01 Jul 2024 15:02:30 +0800, Joy Zou wrote:
> For the details, please check the patch commit log.
> 
> Changes in v2:
> 1. modify the dev_err() log description.
> 2. add review tag.
> 
> Joy Zou (2):
>   dmaengine: fsl-edma: change to guard(mutex) within fsl_edma3_xlate()
>   dmaengine: fsl-edma: add edma src ID check at request channel
> 
> [...]

Applied, thanks!

[1/2] dmaengine: fsl-edma: change to guard(mutex) within fsl_edma3_xlate()
      commit: 90d21f6e57a898ef02810404dd3866acaf707ebf
[2/2] dmaengine: fsl-edma: add edma src ID check at request channel
      commit: 9542961494bf747a73413f925f8ea9ac410a4aec

Best regards,
-- 
~Vinod