media: staging: rkisp1: stats: replace locks wq_lock, irq_lock with one lock

This patch removes two locks in the rkisp1_stats struct:
- The mutex 'wq_lock' that is used to protect the buffers list 'stat'
- The spin_lock 'irq_lock' that is used to protect the
variable 'is_streaming'

It replaces them with one spin_lock 'lock' that protects
both the buffers list and the 'is_streaming' variable.
In later patch the reading of the statistics will move to
the isr so there will be no need for the mutex 'wq_lock'

Signed-off-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Acked-by: Helen Koike <helen.koike@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

diff --git a/drivers/staging/media/rkisp1/rkisp1-common.h b/drivers/staging/media/rkisp1/rkisp1-common.h
index 43fe4dc..d62f5d6 100644 (file)
--- a/drivers/staging/media/rkisp1/rkisp1-common.h
+++ b/drivers/staging/media/rkisp1/rkisp1-common.h
@@ -181,7 +181,7 @@ struct rkisp1_capture {
 /*
  * struct rkisp1_stats - ISP Statistics device
  *
- * @irq_lock: buffer queue lock
+ * @lock: locks the buffer list 'stat' and 'is_streaming'
  * @stat: stats buffer list
  * @readout_wq: workqueue for statistics information read
  */
@@ -189,13 +189,12 @@ struct rkisp1_stats {
        struct rkisp1_vdev_node vnode;
        struct rkisp1_device *rkisp1;
 
-       spinlock_t irq_lock;
+       spinlock_t lock; /* locks 'is_streaming', and 'stats' */
        struct list_head stat;
        struct v4l2_format vdev_fmt;
        bool is_streaming;
 
        struct workqueue_struct *readout_wq;
-       struct mutex wq_lock;
 };
 
 /*

diff --git a/drivers/staging/media/rkisp1/rkisp1-stats.c b/drivers/staging/media/rkisp1/rkisp1-stats.c
index d4f0df4..58329e6 100644 (file)
--- a/drivers/staging/media/rkisp1/rkisp1-stats.c
+++ b/drivers/staging/media/rkisp1/rkisp1-stats.c
@@ -133,9 +133,9 @@ static void rkisp1_stats_vb2_buf_queue(struct vb2_buffer *vb)
 
        stats_buf->vaddr[0] = vb2_plane_vaddr(vb, 0);
 
-       mutex_lock(&stats_dev->wq_lock);
+       spin_lock_irq(&stats_dev->lock);
        list_add_tail(&stats_buf->queue, &stats_dev->stat);
-       mutex_unlock(&stats_dev->wq_lock);
+       spin_unlock_irq(&stats_dev->lock);
 }
 
 static int rkisp1_stats_vb2_buf_prepare(struct vb2_buffer *vb)
@@ -155,13 +155,13 @@ static void rkisp1_stats_vb2_stop_streaming(struct vb2_queue *vq)
        unsigned int i;
 
        /* Make sure no new work queued in isr before draining wq */
-       spin_lock_irq(&stats->irq_lock);
+       spin_lock_irq(&stats->lock);
        stats->is_streaming = false;
-       spin_unlock_irq(&stats->irq_lock);
+       spin_unlock_irq(&stats->lock);
 
        drain_workqueue(stats->readout_wq);
 
-       mutex_lock(&stats->wq_lock);
+       spin_lock_irq(&stats->lock);
        for (i = 0; i < RKISP1_ISP_STATS_REQ_BUFS_MAX; i++) {
                if (list_empty(&stats->stat))
                        break;
@@ -170,7 +170,7 @@ static void rkisp1_stats_vb2_stop_streaming(struct vb2_queue *vq)
                list_del(&buf->queue);
                vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
        }
-       mutex_unlock(&stats->wq_lock);
+       spin_unlock_irq(&stats->lock);
 }
 
 static int
@@ -340,14 +340,14 @@ rkisp1_stats_send_measurement(struct rkisp1_stats *stats,
                frame_sequence = meas_work->frame_id;
        }
 
-       mutex_lock(&stats->wq_lock);
+       spin_lock_irq(&stats->lock);
        /* get one empty buffer */
        if (!list_empty(&stats->stat)) {
                cur_buf = list_first_entry(&stats->stat,
                                           struct rkisp1_buffer, queue);
                list_del(&cur_buf->queue);
        }
-       mutex_unlock(&stats->wq_lock);
+       spin_unlock_irq(&stats->lock);
 
        if (!cur_buf)
                return;
@@ -396,7 +396,7 @@ void rkisp1_stats_isr(struct rkisp1_stats *stats, u32 isp_ris)
        struct rkisp1_isp_readout_work *work;
        unsigned int isp_mis_tmp = 0;
 
-       spin_lock(&stats->irq_lock);
+       spin_lock(&stats->lock);
 
        rkisp1_write(rkisp1, RKISP1_STATS_MEAS_MASK, RKISP1_CIF_ISP_ICR);
 
@@ -425,7 +425,7 @@ void rkisp1_stats_isr(struct rkisp1_stats *stats, u32 isp_ris)
        }
 
 unlock:
-       spin_unlock(&stats->irq_lock);
+       spin_unlock(&stats->lock);
 }
 
 static void rkisp1_init_stats(struct rkisp1_stats *stats)
@@ -445,10 +445,9 @@ int rkisp1_stats_register(struct rkisp1_stats *stats,
        int ret;
 
        stats->rkisp1 = rkisp1;
-       mutex_init(&stats->wq_lock);
        mutex_init(&node->vlock);
        INIT_LIST_HEAD(&stats->stat);
-       spin_lock_init(&stats->irq_lock);
+       spin_lock_init(&stats->lock);
 
        strscpy(vdev->name, RKISP1_STATS_DEV_NAME, sizeof(vdev->name));
 
@@ -495,7 +494,6 @@ err_cleanup_media_entity:
 err_release_queue:
        vb2_queue_release(vdev->queue);
        mutex_destroy(&node->vlock);
-       mutex_destroy(&stats->wq_lock);
        return ret;
 }
 
@@ -509,5 +507,4 @@ void rkisp1_stats_unregister(struct rkisp1_stats *stats)
        media_entity_cleanup(&vdev->entity);
        vb2_queue_release(vdev->queue);
        mutex_destroy(&node->vlock);
-       mutex_destroy(&stats->wq_lock);
 }