media i.MX27 camera: remove legacy dma support

The i.MX27 dma support was introduced with the initial commit of this driver and originally created by me. However, I never got this stable due to the racy dma engine and used the EMMA engine instead. As the DMA support is most probably unused and broken in its current state, remove it. This also helps us to get rid of another user of the legacy i.MX DMA support,
Also, remove the dependency on ARCH_MX* macros as these are scheduled for removal.

Signed-off-by Sascha Hauer <[email protected]>

Cc Baruch Siach <[email protected]>

Cc linux-media at vger.kernel.org

Cc Guennadi Liakhovetski <[email protected]>

---
 drivers/media/video/Kconfig      |    2 +-
 drivers/media/video/mx2_camera.c |  183 --------------------------------------
 2 files changed, 1 insertions(+), 184 deletions(-)

drivers/media/video/Kconfig +1 -1

index f574dc0..27b41b8 100644
@@ -941,7 +941,7 @@ config VIDEO_MX2_HOSTSUPPORT
 
 config VIDEO_MX2
 	tristate "i.MX27/i.MX25 Camera Sensor Interface driver"
-	depends on VIDEO_DEV && SOC_CAMERA && (MACH_MX27 || ARCH_MX25)
+	depends on VIDEO_DEV && SOC_CAMERA && ARCH_MXC
 	select VIDEOBUF_DMA_CONTIG
 	select VIDEO_MX2_HOSTSUPPORT
 	---help---

drivers/media/video/mx2_camera.c +0 -27

index ec2410c..3b5c8eb 100644
@@ -38,9 +38,6 @@
 #include <linux/videodev2.h>
 
 #include <mach/mx2_cam.h>
-#ifdef CONFIG_MACH_MX27
-#include <mach/dma-mx1-mx2.h>
-#endif
 #include <mach/hardware.h>
 
 #include <asm/dma.h>

@@ -330,41 +327,10 @@ static void mx2_camera_remove_device(struct soc_camera_device *icd)
 	pcdev->icd = NULL;
 }
 
-#ifdef CONFIG_MACH_MX27
-static void mx27_camera_dma_enable(struct mx2_camera_dev *pcdev)
-{
-	u32 tmp;
-
-	imx_dma_enable(pcdev->dma);
-
-	tmp = readl(pcdev->base_csi + CSICR1);
-	tmp |= CSICR1_RF_OR_INTEN;
-	writel(tmp, pcdev->base_csi + CSICR1);
-}
-
-static irqreturn_t mx27_camera_irq(int irq_csi, void *data)
-{
-	struct mx2_camera_dev *pcdev = data;
-	u32 status = readl(pcdev->base_csi + CSISR);
-
-	if (status & CSISR_SOF_INT && pcdev->active) {
-		u32 tmp;
-
-		tmp = readl(pcdev->base_csi + CSICR1);
-		writel(tmp | CSICR1_CLR_RXFIFO, pcdev->base_csi + CSICR1);
-		mx27_camera_dma_enable(pcdev);
-	}

drivers/media/video/mx2_camera.c +0 -10

-#ifdef CONFIG_MACH_MX27
-	} else if (cpu_is_mx27()) {
-		int ret;
-
-		if (pcdev->active == NULL) {
-			ret = imx_dma_setup_single(pcdev->dma,
-					videobuf_to_dma_contig(vb), vb->size,
-					(u32)pcdev->base_dma + 0x10,
-					DMA_MODE_READ);
-			if (ret) {

drivers/media/video/mx2_camera.c +0 -120

 		u32 csicr3, dma_inten = 0;
 

@@ -1037,117 +984,6 @@ static int mx2_camera_reqbufs(struct soc_camera_device *icd,
 	return 0;
 }
 
-#ifdef CONFIG_MACH_MX27
-static void mx27_camera_frame_done(struct mx2_camera_dev *pcdev, int state)
-{
-	struct videobuf_buffer *vb;
-	struct mx2_buffer *buf;
-	unsigned long flags;
-	int ret;
-
-	spin_lock_irqsave(&pcdev->lock, flags);
-
-	if (!pcdev->active) {
-		dev_err(pcdev->dev, "%s called with no active buffer!\n",
-				__func__);
-		goto out;
-	}
-
-	vb = &pcdev->active->vb;
-	buf = container_of(vb, struct mx2_buffer, vb);
-	WARN_ON(list_empty(&vb->queue));
-	dev_dbg(pcdev->dev, "%s (vb=0x%p) 0x%08lx %d\n", __func__,
-		vb, vb->baddr, vb->bsize);
-
-	/* _init is used to debug races, see comment in pxa_camera_reqbufs() */
-	list_del_init(&vb->queue);
-	vb->state = state;
-	do_gettimeofday(&vb->ts);
-	vb->field_count++;
-
-	wake_up(&vb->done);
-
-	if (list_empty(&pcdev->capture)) {
-		pcdev->active = NULL;
-		goto out;
-	}
-
-	pcdev->active = list_entry(pcdev->capture.next,
-			struct mx2_buffer, vb.queue);
-
-	vb = &pcdev->active->vb;
-	vb->state = VIDEOBUF_ACTIVE;
-
-	ret = imx_dma_setup_single(pcdev->dma, videobuf_to_dma_contig(vb),
-			vb->size, (u32)pcdev->base_dma + 0x10, DMA_MODE_READ);
-
-	if (ret) {
-		vb->state = VIDEOBUF_ERROR;
-		pcdev->active = NULL;
-		wake_up(&vb->done);
-	}
-
-out:
-	spin_unlock_irqrestore(&pcdev->lock, flags);
-}
-
-static void mx27_camera_dma_err_callback(int channel, void *data, int err)
-{
-	struct mx2_camera_dev *pcdev = data;
-
-	mx27_camera_frame_done(pcdev, VIDEOBUF_ERROR);
-}
-
-static void mx27_camera_dma_callback(int channel, void *data)
-{
-	struct mx2_camera_dev *pcdev = data;
-
-	mx27_camera_frame_done(pcdev, VIDEOBUF_DONE);
-}
-
-#define DMA_REQ_CSI_RX          31 /* FIXME: Add this to a resource */
-
-static int __devinit mx27_camera_dma_init(struct platform_device *pdev,
-		struct mx2_camera_dev *pcdev)
-{
-	int err;
-
-	pcdev->dma = imx_dma_request_by_prio("CSI RX DMA", DMA_PRIO_HIGH);
-	if (pcdev->dma < 0) {
-		dev_err(&pdev->dev, "%s failed to request DMA channel\n",
-				__func__);
-		return pcdev->dma;
-	}
-
-	err = imx_dma_setup_handlers(pcdev->dma, mx27_camera_dma_callback,
-					mx27_camera_dma_err_callback, pcdev);
-	if (err) {
-		dev_err(&pdev->dev, "%s failed to set DMA callback\n",
-				__func__);
-		goto err_out;
-	}
-
-	err = imx_dma_config_channel(pcdev->dma,
-			IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_FIFO,
-			IMX_DMA_MEMSIZE_32 | IMX_DMA_TYPE_LINEAR,
-			DMA_REQ_CSI_RX, 1);
-	if (err) {
-		dev_err(&pdev->dev, "%s failed to config DMA channel\n",
-				__func__);
-		goto err_out;
-	}
-
-	imx_dma_config_burstlen(pcdev->dma, 64);
-
-	return 0;
-
-err_out:
-	imx_dma_free(pcdev->dma);
-
-	return err;
-}
-#endif /* CONFIG_MACH_MX27 */
-
 static unsigned int mx2_camera_poll(struct file *file, poll_table *pt)
 {
 	struct soc_camera_device *icd = file->private_data;

@@ -1352,15 +1188,6 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
 	dev_dbg(&pdev->dev, "Camera clock frequency: %ld\n",
 			clk_get_rate(pcdev->clk_csi));
 
-	/* Initialize DMA */
-#ifdef CONFIG_MACH_MX27
-	if (cpu_is_mx27()) {
-		err = mx27_camera_dma_init(pdev, pcdev);
-		if (err)
-			goto exit_clk_put;
-	}
-#endif /* CONFIG_MACH_MX27 */
-
 	pcdev->res_csi = res_csi;
 	pcdev->pdata = pdev->dev.platform_data;
 	if (pcdev->pdata) {

drivers/media/video/mx2_camera.c +0 -4

 exit_kfree:
 	kfree(pcdev);
 exit:

@@ -1472,10 +1293,6 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
 	struct resource *res;
 
 	clk_put(pcdev->clk_csi);
-#ifdef CONFIG_MACH_MX27
-	if (cpu_is_mx27())
-		imx_dma_free(pcdev->dma);
-#endif /* CONFIG_MACH_MX27 */
 	free_irq(pcdev->irq_csi, pcdev);
 	if (mx27_camera_emma(pcdev))
 		free_irq(pcdev->irq_emma, pcdev);

Signature · 1 line

1.7.5.4

Sure, if it's broken, let's remove it. But there are a couple of points, that we have to fix in this patch. Sorry, a stupid question: has this been tested on i.MX27?

drivers/media/video/mx2_camera.c static void mx2_camera_remove_device(struct soc_camera_device *icd) · line 333

Quoted 7 lines

drivers/media/video/mx2_camera.c +0 -3

-	return IRQ_HANDLED;
-}
-#else
 static irqreturn_t mx27_camera_irq(int irq_csi, void *data)
 {
 	return IRQ_NONE;
 }

If this is really all, what's needed for i.MX27 ISR, let's remove it completely. But maybe you could explain to me, how it is now supposed to work on i.MX27. In probe() we have

	irq_handler_t mx2_cam_irq_handler = cpu_is_mx25() ? mx25_camera_irq
		: mx27_camera_irq;

	...

	err = request_irq(pcdev->irq_csi, mx2_cam_irq_handler, 0,
			MX2_CAM_DRV_NAME, pcdev);

So, after this patch i.MX27 will always have a dummy camera ISR and just use EMMA, right?

Then maybe we have to make EMMA resource availability compulsory on those SoCs, and not optional, as now? You'll have to make emma the only possibility on i.MX27, then pcdev->use_emma will disappear, locations like

Hi Guennadi,

Quoted 3 lines · Guennadi Liakhovetski

Sure, if it's broken, let's remove it. But there are a couple of points, that we have to fix in this patch. Sorry, a stupid question: has this been tested on i.MX27?

Nope, I currently do not have mainline board support for this driver. Could be a good opportunity to add some...

Your other points are totally valid and I will fix them in the next round. Let's first see if someone proves me wrong and says this dma support is indeed working.

Quoted 20 lines

drivers/media/video/mx2_camera.c static void mx2_camera_remove_device(struct soc_camera_device *icd) · line 333

Quoted 7 lines

drivers/media/video/mx2_camera.c +0 -3

-	return IRQ_HANDLED;
-}
-#else
 static irqreturn_t mx27_camera_irq(int irq_csi, void *data)
 {
 	return IRQ_NONE;
 }

If this is really all, what's needed for i.MX27 ISR, let's remove it completely. But maybe you could explain to me, how it is now supposed to work on i.MX27. In probe() we have

	irq_handler_t mx2_cam_irq_handler = cpu_is_mx25() ? mx25_camera_irq
		: mx27_camera_irq;

	...

	err = request_irq(pcdev->irq_csi, mx2_cam_irq_handler, 0,
			MX2_CAM_DRV_NAME, pcdev);

Quoted 2 lines

So, after this patch i.MX27 will always have a dummy camera ISR and just use EMMA, right?

Yes, only the EMMA irq is used, we can remove this one.

Quoted 4 lines

Then maybe we have to make EMMA resource availability compulsory on those SoCs, and not optional, as now? You'll have to make emma the only possibility on i.MX27, then pcdev->use_emma will disappear, locations like

ok.

Sascha

Signature · 4 lines

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(hope, you've had good holidays:-))

Any update on this? Do we want this for 3.2?

Quoted 14 lines

The i.MX27 dma support was introduced with the initial commit of this driver and originally created by me. However, I never got this stable due to the racy dma engine and used the EMMA engine instead. As the DMA support is most probably unused and broken in its current state, remove it. This also helps us to get rid of another user of the legacy i.MX DMA support,
Also, remove the dependency on ARCH_MX* macros as these are scheduled for removal.

Signed-off-by Sascha Hauer <[email protected]>

Cc Baruch Siach <[email protected]>

Cc linux-media at vger.kernel.org

Cc Guennadi Liakhovetski <[email protected]>

---

Baruch, any comment?