[Patch 03/13] media: am437x-vpfe: Rework ISR routine for clarity

Benoit Parrot
2019-09-09T16:26:56Z

Make the ISR code simpler to follow by removing goto and
relocating/eliminating duplicate spinlock accesses.

Signed-off-by: Benoit Parrot <bparrot@ti.com>
---
drivers/media/platform/am437x/am437x-vpfe.c | 128 ++++++++++----------
1 file changed, 66 insertions(+), 62 deletions(-)

diff --git a/drivers/media/platform/am437x/am437x-vpfe.c b/drivers/media/platform/am437x/am437x-vpfe.c
index 0ecb75bf5abd..7c5b734f7143 100644
--- a/drivers/media/platform/am437x/am437x-vpfe.c
+++ b/drivers/media/platform/am437x/am437x-vpfe.c
@@ -1233,22 +1233,29 @@ static int vpfe_open(struct file *file)
* This function will get next buffer from the dma queue and
* set the buffer address in the vpfe register for capture.
* the buffer is marked active
- *
- * Assumes caller is holding vpfe->dma_queue_lock already
*/
-static inline void vpfe_schedule_next_buffer(struct vpfe_device *vpfe)
+static void vpfe_schedule_next_buffer(struct vpfe_device *vpfe)
{
+ dma_addr_t addr;
+
+ spin_lock(&vpfe->dma_queue_lock);
+ if (list_empty(&vpfe->dma_queue)) {
+ spin_unlock(&vpfe->dma_queue_lock);
+ return;
+ }
+
vpfe->next_frm = list_entry(vpfe->dma_queue.next,
struct vpfe_cap_buffer, list);
list_del(&vpfe->next_frm->list);
+ spin_unlock(&vpfe->dma_queue_lock);

- vpfe_set_sdr_addr(&vpfe->ccdc,
- vb2_dma_contig_plane_dma_addr(&vpfe->next_frm->vb.vb2_buf, 0));
+ addr = vb2_dma_contig_plane_dma_addr(&vpfe->next_frm->vb.vb2_buf, 0);
+ vpfe_set_sdr_addr(&vpfe->ccdc, addr);
}

static inline void vpfe_schedule_bottom_field(struct vpfe_device *vpfe)
{
- unsigned long addr;
+ dma_addr_t addr;

addr = vb2_dma_contig_plane_dma_addr(&vpfe->next_frm->vb.vb2_buf, 0) +
vpfe->field_off;
@@ -1273,6 +1280,55 @@ static inline void vpfe_process_buffer_complete(struct vpfe_device *vpfe)
vpfe->cur_frm = vpfe->next_frm;
}

+static void vpfe_handle_interlaced_irq(struct vpfe_device *vpfe,
+ enum v4l2_field field)
+{
+ int fid;
+
+ /* interlaced or TB capture check which field
+ * we are in hardware
+ */
+ fid = vpfe_ccdc_getfid(&vpfe->ccdc);
+
+ /* switch the software maintained field id */
+ vpfe->field ^= 1;
+ if (fid == vpfe->field) {
+ /* we are in-sync here,continue */
+ if (fid == 0) {
+ /*
+ * One frame is just being captured. If the
+ * next frame is available, release the
+ * current frame and move on
+ */
+ if (vpfe->cur_frm != vpfe->next_frm)
+ vpfe_process_buffer_complete(vpfe);
+
+ /*
+ * based on whether the two fields are stored
+ * interleave or separately in memory,
+ * reconfigure the CCDC memory address
+ */
+ if (field == V4L2_FIELD_SEQ_TB)
+ vpfe_schedule_bottom_field(vpfe);
+ } else {
+ /*
+ * if one field is just being captured configure
+ * the next frame get the next frame from the empty
+ * queue if no frame is available hold on to the
+ * current buffer
+ */
+ if (vpfe->cur_frm == vpfe->next_frm)
+ vpfe_schedule_next_buffer(vpfe);
+ }
+ } else if (fid == 0) {
+ /*
+ * out of sync. Recover from any hardware out-of-sync.
+ * May loose one frame
+ */
+ vpfe->field = fid;
+ }
+}
+
/*
* vpfe_isr : ISR handler for vpfe capture (VINT0)
* @irq: irq number
@@ -1284,76 +1340,24 @@ static inline void vpfe_process_buffer_complete(struct vpfe_device *vpfe)
static irqreturn_t vpfe_isr(int irq, void *dev)
{
struct vpfe_device *vpfe = (struct vpfe_device *)dev;
- enum v4l2_field field;
+ enum v4l2_field field = vpfe->fmt.fmt.pix.field;
int intr_status;
- int fid;

intr_status = vpfe_reg_read(&vpfe->ccdc, VPFE_IRQ_STS);

if (intr_status & VPFE_VDINT0) {
- field = vpfe->fmt.fmt.pix.field;
-
if (field == V4L2_FIELD_NONE) {
- /* handle progressive frame capture */
if (vpfe->cur_frm != vpfe->next_frm)
vpfe_process_buffer_complete(vpfe);
- goto next_intr;
- }
-
- /* interlaced or TB capture check which field
- we are in hardware */
- fid = vpfe_ccdc_getfid(&vpfe->ccdc);
-
- /* switch the software maintained field id */
- vpfe->field ^= 1;
- if (fid == vpfe->field) {
- /* we are in-sync here,continue */
- if (fid == 0) {
- /*
- * One frame is just being captured. If the
- * next frame is available, release the
- * current frame and move on
- */
- if (vpfe->cur_frm != vpfe->next_frm)
- vpfe_process_buffer_complete(vpfe);
- /*
- * based on whether the two fields are stored
- * interleave or separately in memory,
- * reconfigure the CCDC memory address
- */
- if (field == V4L2_FIELD_SEQ_TB)
- vpfe_schedule_bottom_field(vpfe);
-
- goto next_intr;
- }
- /*
- * if one field is just being captured configure
- * the next frame get the next frame from the empty
- * queue if no frame is available hold on to the
- * current buffer
- */
- spin_lock(&vpfe->dma_queue_lock);
- if (!list_empty(&vpfe->dma_queue) &&
- vpfe->cur_frm == vpfe->next_frm)
- vpfe_schedule_next_buffer(vpfe);
- spin_unlock(&vpfe->dma_queue_lock);
- } else if (fid == 0) {
- /*
- * out of sync. Recover from any hardware out-of-sync.
- * May loose one frame
- */
- vpfe->field = fid;
+ } else {
+ vpfe_handle_interlaced_irq(vpfe, field);
}
}

-next_intr:
if (intr_status & VPFE_VDINT1) {
- spin_lock(&vpfe->dma_queue_lock);
- if (vpfe->fmt.fmt.pix.field == V4L2_FIELD_NONE &&
- !list_empty(&vpfe->dma_queue) &&
+ if (field == V4L2_FIELD_NONE &&
vpfe->cur_frm == vpfe->next_frm)
vpfe_schedule_next_buffer(vpfe);
- spin_unlock(&vpfe->dma_queue_lock);
}

vpfe_clear_intr(&vpfe->ccdc, intr_status);
--
2.17.1