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path: root/drivers/media/pci/cx23885/cx23885-vbi.c
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Diffstat (limited to 'drivers/media/pci/cx23885/cx23885-vbi.c')
-rw-r--r--drivers/media/pci/cx23885/cx23885-vbi.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/drivers/media/pci/cx23885/cx23885-vbi.c b/drivers/media/pci/cx23885/cx23885-vbi.c
new file mode 100644
index 000000000..4bdd2bea3
--- /dev/null
+++ b/drivers/media/pci/cx23885/cx23885-vbi.c
@@ -0,0 +1,256 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for the Conexant CX23885 PCIe bridge
+ *
+ * Copyright (c) 2007 Steven Toth <stoth@linuxtv.org>
+ */
+
+#include "cx23885.h"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/init.h>
+
+static unsigned int vbibufs = 4;
+module_param(vbibufs, int, 0644);
+MODULE_PARM_DESC(vbibufs, "number of vbi buffers, range 2-32");
+
+static unsigned int vbi_debug;
+module_param(vbi_debug, int, 0644);
+MODULE_PARM_DESC(vbi_debug, "enable debug messages [vbi]");
+
+#define dprintk(level, fmt, arg...)\
+ do { if (vbi_debug >= level)\
+ printk(KERN_DEBUG pr_fmt("%s: vbi:" fmt), \
+ __func__, ##arg); \
+ } while (0)
+
+/* ------------------------------------------------------------------ */
+
+#define VBI_LINE_LENGTH 1440
+#define VBI_NTSC_LINE_COUNT 12
+#define VBI_PAL_LINE_COUNT 18
+
+
+int cx23885_vbi_fmt(struct file *file, void *priv,
+ struct v4l2_format *f)
+{
+ struct cx23885_dev *dev = video_drvdata(file);
+
+ f->fmt.vbi.sampling_rate = 27000000;
+ f->fmt.vbi.samples_per_line = VBI_LINE_LENGTH;
+ f->fmt.vbi.sample_format = V4L2_PIX_FMT_GREY;
+ f->fmt.vbi.offset = 0;
+ f->fmt.vbi.flags = 0;
+ if (dev->tvnorm & V4L2_STD_525_60) {
+ /* ntsc */
+ f->fmt.vbi.start[0] = V4L2_VBI_ITU_525_F1_START + 9;
+ f->fmt.vbi.start[1] = V4L2_VBI_ITU_525_F2_START + 9;
+ f->fmt.vbi.count[0] = VBI_NTSC_LINE_COUNT;
+ f->fmt.vbi.count[1] = VBI_NTSC_LINE_COUNT;
+ } else if (dev->tvnorm & V4L2_STD_625_50) {
+ /* pal */
+ f->fmt.vbi.start[0] = V4L2_VBI_ITU_625_F1_START + 5;
+ f->fmt.vbi.start[1] = V4L2_VBI_ITU_625_F2_START + 5;
+ f->fmt.vbi.count[0] = VBI_PAL_LINE_COUNT;
+ f->fmt.vbi.count[1] = VBI_PAL_LINE_COUNT;
+ }
+
+ return 0;
+}
+
+/* We're given the Video Interrupt status register.
+ * The cx23885_video_irq() func has already validated
+ * the potential error bits, we just need to
+ * deal with vbi payload and return indication if
+ * we actually processed any payload.
+ */
+int cx23885_vbi_irq(struct cx23885_dev *dev, u32 status)
+{
+ u32 count;
+ int handled = 0;
+
+ if (status & VID_BC_MSK_VBI_RISCI1) {
+ dprintk(1, "%s() VID_BC_MSK_VBI_RISCI1\n", __func__);
+ spin_lock(&dev->slock);
+ count = cx_read(VBI_A_GPCNT);
+ cx23885_video_wakeup(dev, &dev->vbiq, count);
+ spin_unlock(&dev->slock);
+ handled++;
+ }
+
+ return handled;
+}
+
+static int cx23885_start_vbi_dma(struct cx23885_dev *dev,
+ struct cx23885_dmaqueue *q,
+ struct cx23885_buffer *buf)
+{
+ dprintk(1, "%s()\n", __func__);
+
+ /* setup fifo + format */
+ cx23885_sram_channel_setup(dev, &dev->sram_channels[SRAM_CH02],
+ VBI_LINE_LENGTH, buf->risc.dma);
+
+ /* reset counter */
+ cx_write(VID_A_VBI_CTRL, 3);
+ cx_write(VBI_A_GPCNT_CTL, 3);
+ q->count = 0;
+
+ /* enable irq */
+ cx23885_irq_add_enable(dev, 0x01);
+ cx_set(VID_A_INT_MSK, 0x000022);
+
+ /* start dma */
+ cx_set(DEV_CNTRL2, (1<<5));
+ cx_set(VID_A_DMA_CTL, 0x22); /* FIFO and RISC enable */
+
+ return 0;
+}
+
+/* ------------------------------------------------------------------ */
+
+static int queue_setup(struct vb2_queue *q,
+ unsigned int *num_buffers, unsigned int *num_planes,
+ unsigned int sizes[], struct device *alloc_devs[])
+{
+ struct cx23885_dev *dev = q->drv_priv;
+ unsigned lines = VBI_PAL_LINE_COUNT;
+
+ if (dev->tvnorm & V4L2_STD_525_60)
+ lines = VBI_NTSC_LINE_COUNT;
+ *num_planes = 1;
+ sizes[0] = lines * VBI_LINE_LENGTH * 2;
+ return 0;
+}
+
+static int buffer_prepare(struct vb2_buffer *vb)
+{
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct cx23885_dev *dev = vb->vb2_queue->drv_priv;
+ struct cx23885_buffer *buf = container_of(vbuf,
+ struct cx23885_buffer, vb);
+ struct sg_table *sgt = vb2_dma_sg_plane_desc(vb, 0);
+ unsigned lines = VBI_PAL_LINE_COUNT;
+
+ if (dev->tvnorm & V4L2_STD_525_60)
+ lines = VBI_NTSC_LINE_COUNT;
+
+ if (vb2_plane_size(vb, 0) < lines * VBI_LINE_LENGTH * 2)
+ return -EINVAL;
+ vb2_set_plane_payload(vb, 0, lines * VBI_LINE_LENGTH * 2);
+
+ cx23885_risc_vbibuffer(dev->pci, &buf->risc,
+ sgt->sgl,
+ 0, VBI_LINE_LENGTH * lines,
+ VBI_LINE_LENGTH, 0,
+ lines);
+ return 0;
+}
+
+static void buffer_finish(struct vb2_buffer *vb)
+{
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct cx23885_buffer *buf = container_of(vbuf,
+ struct cx23885_buffer, vb);
+
+ cx23885_free_buffer(vb->vb2_queue->drv_priv, buf);
+}
+
+/*
+ * The risc program for each buffer works as follows: it starts with a simple
+ * 'JUMP to addr + 12', which is effectively a NOP. Then the code to DMA the
+ * buffer follows and at the end we have a JUMP back to the start + 12 (skipping
+ * the initial JUMP).
+ *
+ * This is the risc program of the first buffer to be queued if the active list
+ * is empty and it just keeps DMAing this buffer without generating any
+ * interrupts.
+ *
+ * If a new buffer is added then the initial JUMP in the code for that buffer
+ * will generate an interrupt which signals that the previous buffer has been
+ * DMAed successfully and that it can be returned to userspace.
+ *
+ * It also sets the final jump of the previous buffer to the start of the new
+ * buffer, thus chaining the new buffer into the DMA chain. This is a single
+ * atomic u32 write, so there is no race condition.
+ *
+ * The end-result of all this that you only get an interrupt when a buffer
+ * is ready, so the control flow is very easy.
+ */
+static void buffer_queue(struct vb2_buffer *vb)
+{
+ struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+ struct cx23885_dev *dev = vb->vb2_queue->drv_priv;
+ struct cx23885_buffer *buf = container_of(vbuf,
+ struct cx23885_buffer, vb);
+ struct cx23885_buffer *prev;
+ struct cx23885_dmaqueue *q = &dev->vbiq;
+ unsigned long flags;
+
+ buf->risc.cpu[1] = cpu_to_le32(buf->risc.dma + 12);
+ buf->risc.jmp[0] = cpu_to_le32(RISC_JUMP | RISC_CNT_INC);
+ buf->risc.jmp[1] = cpu_to_le32(buf->risc.dma + 12);
+ buf->risc.jmp[2] = cpu_to_le32(0); /* bits 63-32 */
+
+ if (list_empty(&q->active)) {
+ spin_lock_irqsave(&dev->slock, flags);
+ list_add_tail(&buf->queue, &q->active);
+ spin_unlock_irqrestore(&dev->slock, flags);
+ dprintk(2, "[%p/%d] vbi_queue - first active\n",
+ buf, buf->vb.vb2_buf.index);
+
+ } else {
+ buf->risc.cpu[0] |= cpu_to_le32(RISC_IRQ1);
+ prev = list_entry(q->active.prev, struct cx23885_buffer,
+ queue);
+ spin_lock_irqsave(&dev->slock, flags);
+ list_add_tail(&buf->queue, &q->active);
+ spin_unlock_irqrestore(&dev->slock, flags);
+ prev->risc.jmp[1] = cpu_to_le32(buf->risc.dma);
+ dprintk(2, "[%p/%d] buffer_queue - append to active\n",
+ buf, buf->vb.vb2_buf.index);
+ }
+}
+
+static int cx23885_start_streaming(struct vb2_queue *q, unsigned int count)
+{
+ struct cx23885_dev *dev = q->drv_priv;
+ struct cx23885_dmaqueue *dmaq = &dev->vbiq;
+ struct cx23885_buffer *buf = list_entry(dmaq->active.next,
+ struct cx23885_buffer, queue);
+
+ cx23885_start_vbi_dma(dev, dmaq, buf);
+ return 0;
+}
+
+static void cx23885_stop_streaming(struct vb2_queue *q)
+{
+ struct cx23885_dev *dev = q->drv_priv;
+ struct cx23885_dmaqueue *dmaq = &dev->vbiq;
+ unsigned long flags;
+
+ cx_clear(VID_A_DMA_CTL, 0x22); /* FIFO and RISC enable */
+ spin_lock_irqsave(&dev->slock, flags);
+ while (!list_empty(&dmaq->active)) {
+ struct cx23885_buffer *buf = list_entry(dmaq->active.next,
+ struct cx23885_buffer, queue);
+
+ list_del(&buf->queue);
+ vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_ERROR);
+ }
+ spin_unlock_irqrestore(&dev->slock, flags);
+}
+
+
+const struct vb2_ops cx23885_vbi_qops = {
+ .queue_setup = queue_setup,
+ .buf_prepare = buffer_prepare,
+ .buf_finish = buffer_finish,
+ .buf_queue = buffer_queue,
+ .wait_prepare = vb2_ops_wait_prepare,
+ .wait_finish = vb2_ops_wait_finish,
+ .start_streaming = cx23885_start_streaming,
+ .stop_streaming = cx23885_stop_streaming,
+};