media: cedrus: Remove global IRQ spin lock from the driver

We initially introduced a spin lock to ensure that the VPU registers
are not accessed concurrently between our setup function and IRQ
handler. The V4L2 M2M API ensures that only one decoding job runs at a
time, so the interrupt signaling the end of decoding will not occur
while the next picture is being configured.

Spurious interrupts are taken care of in the handler, by checking that
we have a valid M2M context and a decoding status available before
marking the buffers as done.

In addition, holding a spin lock could be problematic if non-atomic
operations are required in the setup process for future codec support.

As a result, remove the global IRQ spin lock.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c b/drivers/staging/media/sunxi/cedrus/cedrus.c
index b538eb0321d8284a18414dec6cdc954a06fe730c..c28c70ac7c818c301d218393c650f48d402cb99a 100644 (file)
--- a/drivers/staging/media/sunxi/cedrus/cedrus.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus.c
@@ -279,7 +279,6 @@ static int cedrus_probe(struct platform_device *pdev)
        dev->dec_ops[CEDRUS_CODEC_MPEG2] = &cedrus_dec_ops_mpeg2;
 
        mutex_init(&dev->dev_mutex);
-       spin_lock_init(&dev->irq_lock);
 
        ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev);
        if (ret) {

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.h b/drivers/staging/media/sunxi/cedrus/cedrus.h
index 3f61248c57ac1c85669d5e2aad97df4560d58268..3acfdcf8369128735f0489945389244227bca138 100644 (file)
--- a/drivers/staging/media/sunxi/cedrus/cedrus.h
+++ b/drivers/staging/media/sunxi/cedrus/cedrus.h
@@ -105,8 +105,6 @@ struct cedrus_dev {
 
        /* Device file mutex */
        struct mutex            dev_mutex;
-       /* Interrupt spinlock */
-       spinlock_t              irq_lock;
 
        void __iomem            *base;
 

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
index e40180a33951b731a237e06f6804e4a133b34844..6c5e310a7cf72158799d32874cdb3ed00d581750 100644 (file)
--- a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c
@@ -28,7 +28,6 @@ void cedrus_device_run(void *priv)
        struct cedrus_dev *dev = ctx->dev;
        struct cedrus_run run = { 0 };
        struct media_request *src_req;
-       unsigned long flags;
 
        run.src = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx);
        run.dst = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx);
@@ -39,8 +38,6 @@ void cedrus_device_run(void *priv)
        if (src_req)
                v4l2_ctrl_request_setup(src_req, &ctx->hdl);
 
-       spin_lock_irqsave(&ctx->dev->irq_lock, flags);
-
        switch (ctx->src_fmt.pixelformat) {
        case V4L2_PIX_FMT_MPEG2_SLICE:
                run.mpeg2.slice_params = cedrus_find_control_data(ctx,
@@ -55,16 +52,10 @@ void cedrus_device_run(void *priv)
 
        dev->dec_ops[ctx->current_codec]->setup(ctx, &run);
 
-       spin_unlock_irqrestore(&ctx->dev->irq_lock, flags);
-
        /* Complete request(s) controls if needed. */
 
        if (src_req)
                v4l2_ctrl_request_complete(src_req, &ctx->hdl);
 
-       spin_lock_irqsave(&ctx->dev->irq_lock, flags);
-
        dev->dec_ops[ctx->current_codec]->trigger(ctx);
-
-       spin_unlock_irqrestore(&ctx->dev->irq_lock, flags);
 }

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
index 493e65b17b307c8e7e06b951279f23ff414ba361..243592a5425e488874180e4804e48851e1290663 100644 (file)
--- a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c
@@ -105,24 +105,17 @@ static irqreturn_t cedrus_irq(int irq, void *data)
        struct vb2_v4l2_buffer *src_buf, *dst_buf;
        enum vb2_buffer_state state;
        enum cedrus_irq_status status;
-       unsigned long flags;
-
-       spin_lock_irqsave(&dev->irq_lock, flags);
 
        ctx = v4l2_m2m_get_curr_priv(dev->m2m_dev);
        if (!ctx) {
                v4l2_err(&dev->v4l2_dev,
                         "Instance released before the end of transaction\n");
-               spin_unlock_irqrestore(&dev->irq_lock, flags);
-
                return IRQ_NONE;
        }
 
        status = dev->dec_ops[ctx->current_codec]->irq_status(ctx);
-       if (status == CEDRUS_IRQ_NONE) {
-               spin_unlock_irqrestore(&dev->irq_lock, flags);
+       if (status == CEDRUS_IRQ_NONE)
                return IRQ_NONE;
-       }
 
        dev->dec_ops[ctx->current_codec]->irq_disable(ctx);
        dev->dec_ops[ctx->current_codec]->irq_clear(ctx);
@@ -133,8 +126,6 @@ static irqreturn_t cedrus_irq(int irq, void *data)
        if (!src_buf || !dst_buf) {
                v4l2_err(&dev->v4l2_dev,
                         "Missing source and/or destination buffers\n");
-               spin_unlock_irqrestore(&dev->irq_lock, flags);
-
                return IRQ_HANDLED;
        }
 
@@ -146,8 +137,6 @@ static irqreturn_t cedrus_irq(int irq, void *data)
        v4l2_m2m_buf_done(src_buf, state);
        v4l2_m2m_buf_done(dst_buf, state);
 
-       spin_unlock_irqrestore(&dev->irq_lock, flags);
-
        v4l2_m2m_job_finish(ctx->dev->m2m_dev, ctx->fh.m2m_ctx);
 
        return IRQ_HANDLED;

diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
index 5c5fce678b93e45b349b7cb0cd44dfcb1530a67a..8721b4a7d4968f327e51f71d0655600bf378e2b4 100644 (file)
--- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c
+++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c
@@ -380,18 +380,13 @@ static void cedrus_queue_cleanup(struct vb2_queue *vq, u32 state)
 {
        struct cedrus_ctx *ctx = vb2_get_drv_priv(vq);
        struct vb2_v4l2_buffer *vbuf;
-       unsigned long flags;
 
        for (;;) {
-               spin_lock_irqsave(&ctx->dev->irq_lock, flags);
-
                if (V4L2_TYPE_IS_OUTPUT(vq->type))
                        vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx);
                else
                        vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx);
 
-               spin_unlock_irqrestore(&ctx->dev->irq_lock, flags);
-
                if (!vbuf)
                        return;