[PATCH v2 0/8] Add matching device node validation in DMA engine core

[PATCH v2 0/8] Add matching device node validation in DMA engine core

[Baolin Wang]

Hi,

This patch set adds a device node validation in DMA engine core, that will
help some drivers to remove the duplicate device node validation in each
driver.

Any comments are welcome. Thanks.

Changes from v1:
 - Add test-by tag from Peter.
 - Use dma_request_channel instead of __dma_request_channel() for
 the fuse-tegra20.c driver to keep bisectable.

Baolin Wang (8):
  dmaengine: Add matching device node validation in
    __dma_request_channel()
  soc: tegra: fuse: Use dma_request_channel instead of
    __dma_request_channel()
  dmaengine: imx-sdma: Let the core do the device node validation
  dmaengine: dma-jz4780: Let the core do the device node validation
  dmaengine: mmp_tdma: Let the core do the device node validation
  dmaengine: mxs-dma: Let the core do the device node validation
  dmaengine: sh: rcar-dmac: Let the core do the device node validation
  dmaengine: sh: usb-dmac: Let the core do the device node validation

 drivers/dma/dma-jz4780.c              |    7 ++-----
 drivers/dma/dmaengine.c               |   10 ++++++++--
 drivers/dma/imx-sdma.c                |    9 ++-------
 drivers/dma/mmp_tdma.c                |   10 ++--------
 drivers/dma/mxs-dma.c                 |    8 ++------
 drivers/dma/of-dma.c                  |    4 ++--
 drivers/dma/sh/rcar-dmac.c            |    6 +++---
 drivers/dma/sh/usb-dmac.c             |    6 ++----
 drivers/soc/tegra/fuse/fuse-tegra20.c |    2 +-
 include/linux/dmaengine.h             |   12 ++++++++----
 include/linux/platform_data/dma-imx.h |    1 -
 11 files changed, 32 insertions(+), 43 deletions(-)

-- 
1.7.9.5

[PATCH v2 1/8] dmaengine: Add matching device node validation in __dma_request_channel()

[Baolin Wang]

When user try to request one DMA channel by __dma_request_channel(), it won't
validate if it is the correct DMA device to request, that will lead each DMA
engine driver to validate the correct device node in their filter function
if it is necessary.

Thus we can add the matching device node validation in the DMA engine core,
to remove all of device node validation in the drivers.

Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/dmaengine.c   |   10 ++++++++--
 drivers/dma/of-dma.c      |    4 ++--
 include/linux/dmaengine.h |   12 ++++++++----
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 3a11b10..610080c 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -641,11 +641,13 @@ struct dma_chan *dma_get_any_slave_channel(struct dma_device *device)
  * @mask: capabilities that the channel must satisfy
  * @fn: optional callback to disposition available channels
  * @fn_param: opaque parameter to pass to dma_filter_fn
+ * @np: device node to look for DMA channels
  *
  * Returns pointer to appropriate DMA channel on success or NULL.
  */
 struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
-				       dma_filter_fn fn, void *fn_param)
+				       dma_filter_fn fn, void *fn_param,
+				       struct device_node *np)
 {
 	struct dma_device *device, *_d;
 	struct dma_chan *chan = NULL;
@@ -653,6 +655,10 @@ struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
 	/* Find a channel */
 	mutex_lock(&dma_list_mutex);
 	list_for_each_entry_safe(device, _d, &dma_device_list, global_node) {
+		/* Finds a DMA controller with matching device node */
+		if (np && device->dev->of_node && np != device->dev->of_node)
+			continue;
+
 		chan = find_candidate(device, mask, fn, fn_param);
 		if (!IS_ERR(chan))
 			break;
@@ -769,7 +775,7 @@ struct dma_chan *dma_request_chan_by_mask(const dma_cap_mask_t *mask)
 	if (!mask)
 		return ERR_PTR(-ENODEV);
 
-	chan = __dma_request_channel(mask, NULL, NULL);
+	chan = __dma_request_channel(mask, NULL, NULL, NULL);
 	if (!chan) {
 		mutex_lock(&dma_list_mutex);
 		if (list_empty(&dma_device_list))
diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 91fd395..6b43d04 100644
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -316,8 +316,8 @@ struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
 	if (count != 1)
 		return NULL;
 
-	return dma_request_channel(info->dma_cap, info->filter_fn,
-			&dma_spec->args[0]);
+	return __dma_request_channel(&info->dma_cap, info->filter_fn,
+				     &dma_spec->args[0], dma_spec->np);
 }
 EXPORT_SYMBOL_GPL(of_dma_simple_xlate);
 
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index d49ec5c..504085b 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -1314,7 +1314,8 @@ static inline enum dma_status dma_async_is_complete(dma_cookie_t cookie,
 enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
 void dma_issue_pending_all(void);
 struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
-					dma_filter_fn fn, void *fn_param);
+				       dma_filter_fn fn, void *fn_param,
+				       struct device_node *np);
 struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
 
 struct dma_chan *dma_request_chan(struct device *dev, const char *name);
@@ -1339,7 +1340,9 @@ static inline void dma_issue_pending_all(void)
 {
 }
 static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
-					      dma_filter_fn fn, void *fn_param)
+						     dma_filter_fn fn,
+						     void *fn_param,
+						     struct device_node *np)
 {
 	return NULL;
 }
@@ -1411,7 +1414,8 @@ static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc)
 void dma_run_dependencies(struct dma_async_tx_descriptor *tx);
 struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
 struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
-#define dma_request_channel(mask, x, y) __dma_request_channel(&(mask), x, y)
+#define dma_request_channel(mask, x, y) \
+	__dma_request_channel(&(mask), x, y, NULL)
 #define dma_request_slave_channel_compat(mask, x, y, dev, name) \
 	__dma_request_slave_channel_compat(&(mask), x, y, dev, name)
 
@@ -1429,6 +1433,6 @@ static inline int dmaengine_desc_free(struct dma_async_tx_descriptor *desc)
 	if (!fn || !fn_param)
 		return NULL;
 
-	return __dma_request_channel(mask, fn, fn_param);
+	return __dma_request_channel(mask, fn, fn_param, NULL);
 }
 #endif /* DMAENGINE_H */
-- 
1.7.9.5

[PATCH v2 2/8] soc: tegra: fuse: Use dma_request_channel instead of __dma_request_channel()

[Baolin Wang]

The __dma_request_channel() prototype has been changed to help to do
device node validation, thus we can use dma_request_channel() instead
of __dma_request_channel() to keep kernel bisectable.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/soc/tegra/fuse/fuse-tegra20.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/soc/tegra/fuse/fuse-tegra20.c b/drivers/soc/tegra/fuse/fuse-tegra20.c
index 49ff017..f40a06f 100644
--- a/drivers/soc/tegra/fuse/fuse-tegra20.c
+++ b/drivers/soc/tegra/fuse/fuse-tegra20.c
@@ -110,7 +110,7 @@ static int tegra20_fuse_probe(struct tegra_fuse *fuse)
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 
-	fuse->apbdma.chan = __dma_request_channel(&mask, dma_filter, NULL);
+	fuse->apbdma.chan = dma_request_channel(mask, dma_filter, NULL);
 	if (!fuse->apbdma.chan)
 		return -EPROBE_DEFER;
 
-- 
1.7.9.5

[PATCH v2 3/8] dmaengine: imx-sdma: Let the core do the device node validation

[Baolin Wang]

Let the DMA engine core do the device node validation instead of drivers.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/imx-sdma.c                |    9 ++-------
 include/linux/platform_data/dma-imx.h |    1 -
 2 files changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/imx-sdma.c b/drivers/dma/imx-sdma.c
index 99d9f43..ca296f0 100644
--- a/drivers/dma/imx-sdma.c
+++ b/drivers/dma/imx-sdma.c
@@ -1934,16 +1934,11 @@ static int sdma_init(struct sdma_engine *sdma)
 static bool sdma_filter_fn(struct dma_chan *chan, void *fn_param)
 {
 	struct sdma_channel *sdmac = to_sdma_chan(chan);
-	struct sdma_engine *sdma = sdmac->sdma;
 	struct imx_dma_data *data = fn_param;
 
 	if (!imx_dma_is_general_purpose(chan))
 		return false;
 
-	/* return false if it's not the right device */
-	if (sdma->dev->of_node != data->of_node)
-		return false;
-
 	sdmac->data = *data;
 	chan->private = &sdmac->data;
 
@@ -1971,9 +1966,9 @@ static struct dma_chan *sdma_xlate(struct of_phandle_args *dma_spec,
 	 * be set to sdmac->event_id1.
 	 */
 	data.dma_request2 = 0;
-	data.of_node = ofdma->of_node;
 
-	return dma_request_channel(mask, sdma_filter_fn, &data);
+	return __dma_request_channel(&mask, sdma_filter_fn, &data,
+				     ofdma->of_node);
 }
 
 static int sdma_probe(struct platform_device *pdev)
diff --git a/include/linux/platform_data/dma-imx.h b/include/linux/platform_data/dma-imx.h
index 9daea8d..7d964e7 100644
--- a/include/linux/platform_data/dma-imx.h
+++ b/include/linux/platform_data/dma-imx.h
@@ -55,7 +55,6 @@ struct imx_dma_data {
 	int dma_request2; /* secondary DMA request line */
 	enum sdma_peripheral_type peripheral_type;
 	int priority;
-	struct device_node *of_node;
 };
 
 static inline int imx_dma_is_ipu(struct dma_chan *chan)
-- 
1.7.9.5

[PATCH v2 4/8] dmaengine: dma-jz4780: Let the core do the device node validation

[Baolin Wang]

Let the DMA engine core do the device node validation instead of drivers.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/dma-jz4780.c |    7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c
index 9ce0a38..7e1d381 100644
--- a/drivers/dma/dma-jz4780.c
+++ b/drivers/dma/dma-jz4780.c
@@ -160,7 +160,6 @@ struct jz4780_dma_dev {
 };
 
 struct jz4780_dma_filter_data {
-	struct device_node *of_node;
 	uint32_t transfer_type;
 	int channel;
 };
@@ -765,8 +764,6 @@ static bool jz4780_dma_filter_fn(struct dma_chan *chan, void *param)
 	struct jz4780_dma_dev *jzdma = jz4780_dma_chan_parent(jzchan);
 	struct jz4780_dma_filter_data *data = param;
 
-	if (jzdma->dma_device.dev->of_node != data->of_node)
-		return false;
 
 	if (data->channel > -1) {
 		if (data->channel != jzchan->id)
@@ -790,7 +787,6 @@ static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec,
 	if (dma_spec->args_count != 2)
 		return NULL;
 
-	data.of_node = ofdma->of_node;
 	data.transfer_type = dma_spec->args[0];
 	data.channel = dma_spec->args[1];
 
@@ -815,7 +811,8 @@ static struct dma_chan *jz4780_of_dma_xlate(struct of_phandle_args *dma_spec,
 		return dma_get_slave_channel(
 			&jzdma->chan[data.channel].vchan.chan);
 	} else {
-		return dma_request_channel(mask, jz4780_dma_filter_fn, &data);
+		return __dma_request_channel(&mask, jz4780_dma_filter_fn, &data,
+					     ofdma->of_node);
 	}
 }
 
-- 
1.7.9.5

[PATCH v2 5/8] dmaengine: mmp_tdma: Let the core do the device node validation

[Baolin Wang]

Let the DMA engine core do the device node validation instead of drivers.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/mmp_tdma.c |   10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/dma/mmp_tdma.c b/drivers/dma/mmp_tdma.c
index 0c56faa0..e76858b 100644
--- a/drivers/dma/mmp_tdma.c
+++ b/drivers/dma/mmp_tdma.c
@@ -586,18 +586,12 @@ static int mmp_tdma_chan_init(struct mmp_tdma_device *tdev,
 }
 
 struct mmp_tdma_filter_param {
-	struct device_node *of_node;
 	unsigned int chan_id;
 };
 
 static bool mmp_tdma_filter_fn(struct dma_chan *chan, void *fn_param)
 {
 	struct mmp_tdma_filter_param *param = fn_param;
-	struct mmp_tdma_chan *tdmac = to_mmp_tdma_chan(chan);
-	struct dma_device *pdma_device = tdmac->chan.device;
-
-	if (pdma_device->dev->of_node != param->of_node)
-		return false;
 
 	if (chan->chan_id != param->chan_id)
 		return false;
@@ -615,13 +609,13 @@ static struct dma_chan *mmp_tdma_xlate(struct of_phandle_args *dma_spec,
 	if (dma_spec->args_count != 1)
 		return NULL;
 
-	param.of_node = ofdma->of_node;
 	param.chan_id = dma_spec->args[0];
 
 	if (param.chan_id >= TDMA_CHANNEL_NUM)
 		return NULL;
 
-	return dma_request_channel(mask, mmp_tdma_filter_fn, &param);
+	return __dma_request_channel(&mask, mmp_tdma_filter_fn, &param,
+				     ofdma->of_node);
 }
 
 static const struct of_device_id mmp_tdma_dt_ids[] = {
-- 
1.7.9.5

[PATCH v2 6/8] dmaengine: mxs-dma: Let the core do the device node validation

[Baolin Wang]

Let the DMA engine core do the device node validation instead of drivers.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/mxs-dma.c |    8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 22cc7f6..8ce5e79 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -716,7 +716,6 @@ static int __init mxs_dma_init(struct mxs_dma_engine *mxs_dma)
 }
 
 struct mxs_dma_filter_param {
-	struct device_node *of_node;
 	unsigned int chan_id;
 };
 
@@ -727,9 +726,6 @@ static bool mxs_dma_filter_fn(struct dma_chan *chan, void *fn_param)
 	struct mxs_dma_engine *mxs_dma = mxs_chan->mxs_dma;
 	int chan_irq;
 
-	if (mxs_dma->dma_device.dev->of_node != param->of_node)
-		return false;
-
 	if (chan->chan_id != param->chan_id)
 		return false;
 
@@ -752,13 +748,13 @@ static struct dma_chan *mxs_dma_xlate(struct of_phandle_args *dma_spec,
 	if (dma_spec->args_count != 1)
 		return NULL;
 
-	param.of_node = ofdma->of_node;
 	param.chan_id = dma_spec->args[0];
 
 	if (param.chan_id >= mxs_dma->nr_channels)
 		return NULL;
 
-	return dma_request_channel(mask, mxs_dma_filter_fn, &param);
+	return __dma_request_channel(&mask, mxs_dma_filter_fn, &param,
+				     ofdma->of_node);
 }
 
 static int __init mxs_dma_probe(struct platform_device *pdev)
-- 
1.7.9.5

[PATCH v2 7/8] dmaengine: sh: rcar-dmac: Let the core do the device node validation

[Baolin Wang]

Let the DMA engine core do the device node validation instead of drivers.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/sh/rcar-dmac.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c
index 33ab1b6..67df54a 100644
--- a/drivers/dma/sh/rcar-dmac.c
+++ b/drivers/dma/sh/rcar-dmac.c
@@ -1654,8 +1654,7 @@ static bool rcar_dmac_chan_filter(struct dma_chan *chan, void *arg)
 	 * Forcing it to call dma_request_channel() and iterate through all
 	 * channels from all controllers is just pointless.
 	 */
-	if (chan->device->device_config != rcar_dmac_device_config ||
-	    dma_spec->np != chan->device->dev->of_node)
+	if (chan->device->device_config != rcar_dmac_device_config)
 		return false;
 
 	return !test_and_set_bit(dma_spec->args[0], dmac->modules);
@@ -1675,7 +1674,8 @@ static struct dma_chan *rcar_dmac_of_xlate(struct of_phandle_args *dma_spec,
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 
-	chan = dma_request_channel(mask, rcar_dmac_chan_filter, dma_spec);
+	chan = __dma_request_channel(&mask, rcar_dmac_chan_filter, dma_spec,
+				     ofdma->of_node);
 	if (!chan)
 		return NULL;
 
-- 
1.7.9.5

[PATCH v2 8/8] dmaengine: sh: usb-dmac: Let the core do the device node validation

[Baolin Wang]

Let the DMA engine core do the device node validation instead of drivers.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/dma/sh/usb-dmac.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/dma/sh/usb-dmac.c b/drivers/dma/sh/usb-dmac.c
index 59403f6..0afabf3 100644
--- a/drivers/dma/sh/usb-dmac.c
+++ b/drivers/dma/sh/usb-dmac.c
@@ -636,9 +636,6 @@ static bool usb_dmac_chan_filter(struct dma_chan *chan, void *arg)
 	struct usb_dmac_chan *uchan = to_usb_dmac_chan(chan);
 	struct of_phandle_args *dma_spec = arg;
 
-	if (dma_spec->np != chan->device->dev->of_node)
-		return false;
-
 	/* USB-DMAC should be used with fixed usb controller's FIFO */
 	if (uchan->index != dma_spec->args[0])
 		return false;
@@ -659,7 +656,8 @@ static struct dma_chan *usb_dmac_of_xlate(struct of_phandle_args *dma_spec,
 	dma_cap_zero(mask);
 	dma_cap_set(DMA_SLAVE, mask);
 
-	chan = dma_request_channel(mask, usb_dmac_chan_filter, dma_spec);
+	chan = __dma_request_channel(&mask, usb_dmac_chan_filter, dma_spec,
+				     ofdma->of_node);
 	if (!chan)
 		return NULL;
 
-- 
1.7.9.5

Re: [PATCH v2 0/8] Add matching device node validation in DMA engine core

[Vinod Koul]

On 20-05-19, 19:32, Baolin Wang wrote:
> Hi,
> 
> This patch set adds a device node validation in DMA engine core, that will
> help some drivers to remove the duplicate device node validation in each
> driver.

Applied all, thanks

-- 
~Vinod