drivers/media/pci/cx23885/cx23885-vbi.c - kernel/bruno - Git at Google

 /*
  *  Driver for the Conexant CX23885 PCIe bridge
  *
  *  Copyright (c) 2007 Steven Toth <stoth@linuxtv.org>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License, or
  *  (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *
  *  GNU General Public License for more details.
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/init.h>

 #include "cx23885.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 "%s/0: " fmt, dev->name, ## 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(VID_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_GPCNT_CTL, 3);
 	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, const void *parg,
 			   unsigned int *num_buffers, unsigned int *num_planes,
 			   unsigned int sizes[], void *alloc_ctxs[])
 {
 	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;
 	alloc_ctxs[0] = dev->alloc_ctx;
 	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);
 }


 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,
 };
	/*
	* Driver for the Conexant CX23885 PCIe bridge
	*
	* Copyright (c) 2007 Steven Toth <stoth@linuxtv.org>
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	*
	* GNU General Public License for more details.
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/moduleparam.h>
	#include <linux/init.h>

	#include "cx23885.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 "%s/0: " fmt, dev->name, ## 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(VID_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_GPCNT_CTL, 3);
	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, const void parg,
	unsigned int num_buffers, unsigned int num_planes,
	unsigned int sizes[], void *alloc_ctxs[])
	{
	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;
	alloc_ctxs[0] = dev->alloc_ctx;
	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);
	}


	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,
	};