[PATCH v3 2/4] media: pxa_camera: move interrupt to tasklet

From: Robert Jarzmik
Date: Wed Jul 29 2015 - 15:43:55 EST


From: Robert Jarzmik <robert.jarzmik@xxxxxxxxx>

In preparation for dmaengine conversion, move the camera interrupt
handling into a tasklet. This won't change the global flow, as this
interrupt is only used to detect the end of frame and activate DMA fifos
handling.

Signed-off-by: Robert Jarzmik <robert.jarzmik@xxxxxxxxx>
---
drivers/media/platform/soc_camera/pxa_camera.c | 44 +++++++++++++++++---------
1 file changed, 29 insertions(+), 15 deletions(-)

diff --git a/drivers/media/platform/soc_camera/pxa_camera.c b/drivers/media/platform/soc_camera/pxa_camera.c
index aa304950bb98..39c7e7519b3c 100644
--- a/drivers/media/platform/soc_camera/pxa_camera.c
+++ b/drivers/media/platform/soc_camera/pxa_camera.c
@@ -223,6 +223,7 @@ struct pxa_camera_dev {

struct pxa_buffer *active;
struct pxa_dma_desc *sg_tail[3];
+ struct tasklet_struct task_eof;

u32 save_cicr[5];
};
@@ -605,6 +606,7 @@ static void pxa_camera_start_capture(struct pxa_camera_dev *pcdev)
unsigned long cicr0;

dev_dbg(pcdev->soc_host.v4l2_dev.dev, "%s\n", __func__);
+ __raw_writel(__raw_readl(pcdev->base + CISR), pcdev->base + CISR);
/* Enable End-Of-Frame Interrupt */
cicr0 = __raw_readl(pcdev->base + CICR0) | CICR0_ENB;
cicr0 &= ~CICR0_EOFM;
@@ -922,13 +924,35 @@ static void pxa_camera_deactivate(struct pxa_camera_dev *pcdev)
clk_disable_unprepare(pcdev->clk);
}

-static irqreturn_t pxa_camera_irq(int irq, void *data)
+static void pxa_camera_eof(unsigned long arg)
{
- struct pxa_camera_dev *pcdev = data;
- unsigned long status, cifr, cicr0;
+ struct pxa_camera_dev *pcdev = (struct pxa_camera_dev *)arg;
+ unsigned long cifr;
struct pxa_buffer *buf;
struct videobuf_buffer *vb;

+ dev_dbg(pcdev->soc_host.v4l2_dev.dev,
+ "Camera interrupt status 0x%x\n",
+ __raw_readl(pcdev->base + CISR));
+
+ /* Reset the FIFOs */
+ cifr = __raw_readl(pcdev->base + CIFR) | CIFR_RESET_F;
+ __raw_writel(cifr, pcdev->base + CIFR);
+
+ pcdev->active = list_first_entry(&pcdev->capture,
+ struct pxa_buffer, vb.queue);
+ vb = &pcdev->active->vb;
+ buf = container_of(vb, struct pxa_buffer, vb);
+ pxa_videobuf_set_actdma(pcdev, buf);
+
+ pxa_dma_start_channels(pcdev);
+}
+
+static irqreturn_t pxa_camera_irq(int irq, void *data)
+{
+ struct pxa_camera_dev *pcdev = data;
+ unsigned long status, cicr0;
+
status = __raw_readl(pcdev->base + CISR);
dev_dbg(pcdev->soc_host.v4l2_dev.dev,
"Camera interrupt status 0x%lx\n", status);
@@ -939,20 +963,9 @@ static irqreturn_t pxa_camera_irq(int irq, void *data)
__raw_writel(status, pcdev->base + CISR);

if (status & CISR_EOF) {
- /* Reset the FIFOs */
- cifr = __raw_readl(pcdev->base + CIFR) | CIFR_RESET_F;
- __raw_writel(cifr, pcdev->base + CIFR);
-
- pcdev->active = list_first_entry(&pcdev->capture,
- struct pxa_buffer, vb.queue);
- vb = &pcdev->active->vb;
- buf = container_of(vb, struct pxa_buffer, vb);
- pxa_videobuf_set_actdma(pcdev, buf);
-
- pxa_dma_start_channels(pcdev);
-
cicr0 = __raw_readl(pcdev->base + CICR0) | CICR0_EOFM;
__raw_writel(cicr0, pcdev->base + CICR0);
+ tasklet_schedule(&pcdev->task_eof);
}

return IRQ_HANDLED;
@@ -1847,6 +1860,7 @@ static int pxa_camera_probe(struct platform_device *pdev)
pcdev->soc_host.priv = pcdev;
pcdev->soc_host.v4l2_dev.dev = &pdev->dev;
pcdev->soc_host.nr = pdev->id;
+ tasklet_init(&pcdev->task_eof, pxa_camera_eof, (unsigned long)pcdev);

err = soc_camera_host_register(&pcdev->soc_host);
if (err)
--
2.1.4

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