From: Pratyush Yadav <p.yadav@ti.com>
Different platforms that use this driver might have different number of
DMA channels allocated for CSI. So only as many DMA contexts can be used
as the number of DMA channels available. Get the number of channels
provided via device tree and only configure that many contexts, and
hence only that many pads.
Reviewed-by: Yemike Abhilash Chandra <y-abhilashchandra@ti.com>
Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
Co-developed-by: Jai Luthra <j-luthra@ti.com>
Signed-off-by: Jai Luthra <j-luthra@ti.com>
Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
---
.../platform/ti/j721e-csi2rx/j721e-csi2rx.c | 42 ++++++++++++++-----
1 file changed, 31 insertions(+), 11 deletions(-)
diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
index 4e1c9db0dcf5..6cab7642aa10 100644
--- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
+++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
@@ -44,7 +44,7 @@
#define TI_CSI2RX_MAX_PIX_PER_CLK 4
#define PSIL_WORD_SIZE_BYTES 16
-#define TI_CSI2RX_NUM_CTX 1
+#define TI_CSI2RX_MAX_CTX 32
/*
* There are no hard limits on the width or height. The DMA engine can handle
@@ -57,8 +57,8 @@
#define TI_CSI2RX_PAD_SINK 0
#define TI_CSI2RX_PAD_FIRST_SOURCE 1
-#define TI_CSI2RX_NUM_SOURCE_PADS 1
-#define TI_CSI2RX_NUM_PADS (1 + TI_CSI2RX_NUM_SOURCE_PADS)
+#define TI_CSI2RX_MAX_SOURCE_PADS TI_CSI2RX_MAX_CTX
+#define TI_CSI2RX_MAX_PADS (1 + TI_CSI2RX_MAX_SOURCE_PADS)
#define DRAIN_TIMEOUT_MS 50
#define DRAIN_BUFFER_SIZE SZ_32K
@@ -118,14 +118,15 @@ struct ti_csi2rx_dev {
void __iomem *shim;
struct mutex mutex; /* To serialize ioctls. */
unsigned int enable_count;
+ unsigned int num_ctx;
struct v4l2_device v4l2_dev;
struct media_device mdev;
struct media_pipeline pipe;
- struct media_pad pads[TI_CSI2RX_NUM_PADS];
+ struct media_pad pads[TI_CSI2RX_MAX_PADS];
struct v4l2_async_notifier notifier;
struct v4l2_subdev *source;
struct v4l2_subdev subdev;
- struct ti_csi2rx_ctx ctx[TI_CSI2RX_NUM_CTX];
+ struct ti_csi2rx_ctx ctx[TI_CSI2RX_MAX_CTX];
u8 pix_per_clk;
/* Buffer to drain stale data from PSI-L endpoint */
struct {
@@ -463,7 +464,7 @@ static int csi_async_notifier_complete(struct v4l2_async_notifier *notifier)
return ret;
/* Create and link video nodes for all DMA contexts */
- for (i = 0; i < TI_CSI2RX_NUM_CTX; i++) {
+ for (i = 0; i < csi->num_ctx; i++) {
struct ti_csi2rx_ctx *ctx = &csi->ctx[i];
struct video_device *vdev = &ctx->vdev;
@@ -1250,10 +1251,11 @@ static int ti_csi2rx_v4l2_init(struct ti_csi2rx_dev *csi)
csi->pads[TI_CSI2RX_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
for (unsigned int i = TI_CSI2RX_PAD_FIRST_SOURCE;
- i < TI_CSI2RX_NUM_PADS; i++)
+ i < TI_CSI2RX_PAD_FIRST_SOURCE + csi->num_ctx; i++)
csi->pads[i].flags = MEDIA_PAD_FL_SOURCE;
- ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(csi->pads),
+ ret = media_entity_pads_init(&sd->entity,
+ TI_CSI2RX_PAD_FIRST_SOURCE + csi->num_ctx,
csi->pads);
if (ret)
goto unregister_media;
@@ -1344,8 +1346,9 @@ static int ti_csi2rx_init_ctx(struct ti_csi2rx_ctx *ctx)
static int ti_csi2rx_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
struct ti_csi2rx_dev *csi;
- int ret, i;
+ int ret, i, count;
csi = devm_kzalloc(&pdev->dev, sizeof(*csi), GFP_KERNEL);
if (!csi)
@@ -1367,13 +1370,29 @@ static int ti_csi2rx_probe(struct platform_device *pdev)
if (!csi->drain.vaddr)
return -ENOMEM;
+ /* Only use as many contexts as the number of DMA channels allocated. */
+ count = of_property_count_strings(np, "dma-names");
+ if (count < 0) {
+ dev_err(csi->dev, "Failed to get DMA channel count: %d\n", count);
+ ret = count;
+ goto err_dma_chan;
+ }
+
+ csi->num_ctx = count;
+ if (csi->num_ctx > TI_CSI2RX_MAX_CTX) {
+ dev_err(csi->dev,
+ "%u DMA channels passed. Maximum is %u.\n",
+ csi->num_ctx, TI_CSI2RX_MAX_CTX);
+ goto err_dma_chan;
+ }
+
mutex_init(&csi->mutex);
ret = ti_csi2rx_v4l2_init(csi);
if (ret)
goto err_v4l2;
- for (i = 0; i < TI_CSI2RX_NUM_CTX; i++) {
+ for (i = 0; i < csi->num_ctx; i++) {
csi->ctx[i].idx = i;
csi->ctx[i].csi = csi;
ret = ti_csi2rx_init_ctx(&csi->ctx[i]);
@@ -1402,6 +1421,7 @@ static int ti_csi2rx_probe(struct platform_device *pdev)
ti_csi2rx_cleanup_v4l2(csi);
err_v4l2:
mutex_destroy(&csi->mutex);
+err_dma_chan:
dma_free_coherent(csi->dev, csi->drain.len, csi->drain.vaddr,
csi->drain.paddr);
return ret;
@@ -1412,7 +1432,7 @@ static void ti_csi2rx_remove(struct platform_device *pdev)
struct ti_csi2rx_dev *csi = platform_get_drvdata(pdev);
unsigned int i;
- for (i = 0; i < TI_CSI2RX_NUM_CTX; i++)
+ for (i = 0; i < csi->num_ctx; i++)
ti_csi2rx_cleanup_ctx(&csi->ctx[i]);
ti_csi2rx_cleanup_notifier(csi);
--
2.34.1Hi Rishikesh,
Quoting Rishikesh Donadkar (2025-08-25 19:55:15)
> From: Pratyush Yadav <p.yadav@ti.com>
>
> Different platforms that use this driver might have different number of
> DMA channels allocated for CSI. So only as many DMA contexts can be used
> as the number of DMA channels available. Get the number of channels
> provided via device tree and only configure that many contexts, and
> hence only that many pads.
>
> Reviewed-by: Yemike Abhilash Chandra <y-abhilashchandra@ti.com>
> Signed-off-by: Pratyush Yadav <p.yadav@ti.com>
> Co-developed-by: Jai Luthra <j-luthra@ti.com>
> Signed-off-by: Jai Luthra <j-luthra@ti.com>
> Signed-off-by: Rishikesh Donadkar <r-donadkar@ti.com>
> ---
> .../platform/ti/j721e-csi2rx/j721e-csi2rx.c | 42 ++++++++++++++-----
> 1 file changed, 31 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> index 4e1c9db0dcf5..6cab7642aa10 100644
> --- a/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> +++ b/drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c
> @@ -44,7 +44,7 @@
>
> #define TI_CSI2RX_MAX_PIX_PER_CLK 4
> #define PSIL_WORD_SIZE_BYTES 16
> -#define TI_CSI2RX_NUM_CTX 1
> +#define TI_CSI2RX_MAX_CTX 32
>
> /*
> * There are no hard limits on the width or height. The DMA engine can handle
> @@ -57,8 +57,8 @@
>
> #define TI_CSI2RX_PAD_SINK 0
> #define TI_CSI2RX_PAD_FIRST_SOURCE 1
> -#define TI_CSI2RX_NUM_SOURCE_PADS 1
> -#define TI_CSI2RX_NUM_PADS (1 + TI_CSI2RX_NUM_SOURCE_PADS)
> +#define TI_CSI2RX_MAX_SOURCE_PADS TI_CSI2RX_MAX_CTX
> +#define TI_CSI2RX_MAX_PADS (1 + TI_CSI2RX_MAX_SOURCE_PADS)
>
> #define DRAIN_TIMEOUT_MS 50
> #define DRAIN_BUFFER_SIZE SZ_32K
> @@ -118,14 +118,15 @@ struct ti_csi2rx_dev {
> void __iomem *shim;
> struct mutex mutex; /* To serialize ioctls. */
> unsigned int enable_count;
> + unsigned int num_ctx;
> struct v4l2_device v4l2_dev;
> struct media_device mdev;
> struct media_pipeline pipe;
> - struct media_pad pads[TI_CSI2RX_NUM_PADS];
> + struct media_pad pads[TI_CSI2RX_MAX_PADS];
> struct v4l2_async_notifier notifier;
> struct v4l2_subdev *source;
> struct v4l2_subdev subdev;
> - struct ti_csi2rx_ctx ctx[TI_CSI2RX_NUM_CTX];
> + struct ti_csi2rx_ctx ctx[TI_CSI2RX_MAX_CTX];
> u8 pix_per_clk;
> /* Buffer to drain stale data from PSI-L endpoint */
> struct {
> @@ -463,7 +464,7 @@ static int csi_async_notifier_complete(struct v4l2_async_notifier *notifier)
> return ret;
>
> /* Create and link video nodes for all DMA contexts */
> - for (i = 0; i < TI_CSI2RX_NUM_CTX; i++) {
> + for (i = 0; i < csi->num_ctx; i++) {
> struct ti_csi2rx_ctx *ctx = &csi->ctx[i];
> struct video_device *vdev = &ctx->vdev;
>
> @@ -1250,10 +1251,11 @@ static int ti_csi2rx_v4l2_init(struct ti_csi2rx_dev *csi)
> csi->pads[TI_CSI2RX_PAD_SINK].flags = MEDIA_PAD_FL_SINK;
>
> for (unsigned int i = TI_CSI2RX_PAD_FIRST_SOURCE;
> - i < TI_CSI2RX_NUM_PADS; i++)
> + i < TI_CSI2RX_PAD_FIRST_SOURCE + csi->num_ctx; i++)
> csi->pads[i].flags = MEDIA_PAD_FL_SOURCE;
>
> - ret = media_entity_pads_init(&sd->entity, ARRAY_SIZE(csi->pads),
> + ret = media_entity_pads_init(&sd->entity,
> + TI_CSI2RX_PAD_FIRST_SOURCE + csi->num_ctx,
> csi->pads);
> if (ret)
> goto unregister_media;
> @@ -1344,8 +1346,9 @@ static int ti_csi2rx_init_ctx(struct ti_csi2rx_ctx *ctx)
>
> static int ti_csi2rx_probe(struct platform_device *pdev)
> {
> + struct device_node *np = pdev->dev.of_node;
> struct ti_csi2rx_dev *csi;
> - int ret, i;
> + int ret, i, count;
>
> csi = devm_kzalloc(&pdev->dev, sizeof(*csi), GFP_KERNEL);
> if (!csi)
> @@ -1367,13 +1370,29 @@ static int ti_csi2rx_probe(struct platform_device *pdev)
> if (!csi->drain.vaddr)
> return -ENOMEM;
>
> + /* Only use as many contexts as the number of DMA channels allocated. */
> + count = of_property_count_strings(np, "dma-names");
> + if (count < 0) {
> + dev_err(csi->dev, "Failed to get DMA channel count: %d\n", count);
> + ret = count;
> + goto err_dma_chan;
> + }
> +
> + csi->num_ctx = count;
> + if (csi->num_ctx > TI_CSI2RX_MAX_CTX) {
> + dev_err(csi->dev,
> + "%u DMA channels passed. Maximum is %u.\n",
> + csi->num_ctx, TI_CSI2RX_MAX_CTX);
> + goto err_dma_chan;
> + }
> +
I get the following errors while compiling:
../drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c:1582:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized]
1582 | if (csi->num_ctx > TI_CSI2RX_MAX_CTX) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c:1627:9: note: uninitialized use occurs here
1627 | return ret;
| ^~~
../drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c:1582:2: note: remove the 'if' if its condition is always false
1582 | if (csi->num_ctx > TI_CSI2RX_MAX_CTX) {
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1583 | dev_err(csi->dev,
| ~~~~~~~~~~~~~~~~~
1584 | "%u DMA channels passed. Maximum is %u.\n",
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1585 | csi->num_ctx, TI_CSI2RX_MAX_CTX);
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1586 | goto err_dma_chan;
| ~~~~~~~~~~~~~~~~~~
1587 | }
| ~
../drivers/media/platform/ti/j721e-csi2rx/j721e-csi2rx.c:1551:9: note: initialize the variable 'ret' to silence this warning
1551 | int ret, i, count;
| ^
| = 0
> mutex_init(&csi->mutex);
>
> ret = ti_csi2rx_v4l2_init(csi);
> if (ret)
> goto err_v4l2;
>
> - for (i = 0; i < TI_CSI2RX_NUM_CTX; i++) {
> + for (i = 0; i < csi->num_ctx; i++) {
> csi->ctx[i].idx = i;
> csi->ctx[i].csi = csi;
> ret = ti_csi2rx_init_ctx(&csi->ctx[i]);
> @@ -1402,6 +1421,7 @@ static int ti_csi2rx_probe(struct platform_device *pdev)
> ti_csi2rx_cleanup_v4l2(csi);
> err_v4l2:
> mutex_destroy(&csi->mutex);
> +err_dma_chan:
> dma_free_coherent(csi->dev, csi->drain.len, csi->drain.vaddr,
> csi->drain.paddr);
> return ret;
> @@ -1412,7 +1432,7 @@ static void ti_csi2rx_remove(struct platform_device *pdev)
> struct ti_csi2rx_dev *csi = platform_get_drvdata(pdev);
> unsigned int i;
>
> - for (i = 0; i < TI_CSI2RX_NUM_CTX; i++)
> + for (i = 0; i < csi->num_ctx; i++)
> ti_csi2rx_cleanup_ctx(&csi->ctx[i]);
>
> ti_csi2rx_cleanup_notifier(csi);
> --
> 2.34.1
>
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