cafe_ccic.c

linux 内核源代码

	i2c_del_adapter(&cam->i2c_adapter);
}


/* ------------------------------------------------------------------- */
/*
 * Deal with the controller.
 */

/*
 * Do everything we think we need to have the interface operating
 * according to the desired format.
 */
static void cafe_ctlr_dma(struct cafe_camera *cam)
{
	/*
	 * Store the first two Y buffers (we aren't supporting
	 * planar formats for now, so no UV bufs).  Then either
	 * set the third if it exists, or tell the controller
	 * to just use two.
	 */
	cafe_reg_write(cam, REG_Y0BAR, cam->dma_handles[0]);
	cafe_reg_write(cam, REG_Y1BAR, cam->dma_handles[1]);
	if (cam->nbufs > 2) {
		cafe_reg_write(cam, REG_Y2BAR, cam->dma_handles[2]);
		cafe_reg_clear_bit(cam, REG_CTRL1, C1_TWOBUFS);
	}
	else
		cafe_reg_set_bit(cam, REG_CTRL1, C1_TWOBUFS);
	cafe_reg_write(cam, REG_UBAR, 0); /* 32 bits only for now */
}

static void cafe_ctlr_image(struct cafe_camera *cam)
{
	int imgsz;
	struct v4l2_pix_format *fmt = &cam->pix_format;

	imgsz = ((fmt->height << IMGSZ_V_SHIFT) & IMGSZ_V_MASK) |
		(fmt->bytesperline & IMGSZ_H_MASK);
	cafe_reg_write(cam, REG_IMGSIZE, imgsz);
	cafe_reg_write(cam, REG_IMGOFFSET, 0);
	/* YPITCH just drops the last two bits */
	cafe_reg_write_mask(cam, REG_IMGPITCH, fmt->bytesperline,
			IMGP_YP_MASK);
	/*
	 * Tell the controller about the image format we are using.
	 */
	switch (cam->pix_format.pixelformat) {
	case V4L2_PIX_FMT_YUYV:
	    cafe_reg_write_mask(cam, REG_CTRL0,
			    C0_DF_YUV|C0_YUV_PACKED|C0_YUVE_YUYV,
			    C0_DF_MASK);
	    break;

	case V4L2_PIX_FMT_RGB444:
	    cafe_reg_write_mask(cam, REG_CTRL0,
			    C0_DF_RGB|C0_RGBF_444|C0_RGB4_XRGB,
			    C0_DF_MASK);
		/* Alpha value? */
	    break;

	case V4L2_PIX_FMT_RGB565:
	    cafe_reg_write_mask(cam, REG_CTRL0,
			    C0_DF_RGB|C0_RGBF_565|C0_RGB5_BGGR,
			    C0_DF_MASK);
	    break;

	default:
	    cam_err(cam, "Unknown format %x\n", cam->pix_format.pixelformat);
	    break;
	}
	/*
	 * Make sure it knows we want to use hsync/vsync.
	 */
	cafe_reg_write_mask(cam, REG_CTRL0, C0_SIF_HVSYNC,
			C0_SIFM_MASK);
}


/*
 * Configure the controller for operation; caller holds the
 * device mutex.
 */
static int cafe_ctlr_configure(struct cafe_camera *cam)
{
	unsigned long flags;

	spin_lock_irqsave(&cam->dev_lock, flags);
	cafe_ctlr_dma(cam);
	cafe_ctlr_image(cam);
	cafe_set_config_needed(cam, 0);
	spin_unlock_irqrestore(&cam->dev_lock, flags);
	return 0;
}

static void cafe_ctlr_irq_enable(struct cafe_camera *cam)
{
	/*
	 * Clear any pending interrupts, since we do not
	 * expect to have I/O active prior to enabling.
	 */
	cafe_reg_write(cam, REG_IRQSTAT, FRAMEIRQS);
	cafe_reg_set_bit(cam, REG_IRQMASK, FRAMEIRQS);
}

static void cafe_ctlr_irq_disable(struct cafe_camera *cam)
{
	cafe_reg_clear_bit(cam, REG_IRQMASK, FRAMEIRQS);
}

/*
 * Make the controller start grabbing images.  Everything must
 * be set up before doing this.
 */
static void cafe_ctlr_start(struct cafe_camera *cam)
{
	/* set_bit performs a read, so no other barrier should be
	   needed here */
	cafe_reg_set_bit(cam, REG_CTRL0, C0_ENABLE);
}

static void cafe_ctlr_stop(struct cafe_camera *cam)
{
	cafe_reg_clear_bit(cam, REG_CTRL0, C0_ENABLE);
}

static void cafe_ctlr_init(struct cafe_camera *cam)
{
	unsigned long flags;

	spin_lock_irqsave(&cam->dev_lock, flags);
	/*
	 * Added magic to bring up the hardware on the B-Test board
	 */
	cafe_reg_write(cam, 0x3038, 0x8);
	cafe_reg_write(cam, 0x315c, 0x80008);
	/*
	 * Go through the dance needed to wake the device up.
	 * Note that these registers are global and shared
	 * with the NAND and SD devices.  Interaction between the
	 * three still needs to be examined.
	 */
	cafe_reg_write(cam, REG_GL_CSR, GCSR_SRS|GCSR_MRS); /* Needed? */
	cafe_reg_write(cam, REG_GL_CSR, GCSR_SRC|GCSR_MRC);
	cafe_reg_write(cam, REG_GL_CSR, GCSR_SRC|GCSR_MRS);
	/*
	 * Here we must wait a bit for the controller to come around.
	 */
	spin_unlock_irqrestore(&cam->dev_lock, flags);
	msleep(5);
	spin_lock_irqsave(&cam->dev_lock, flags);

	cafe_reg_write(cam, REG_GL_CSR, GCSR_CCIC_EN|GCSR_SRC|GCSR_MRC);
	cafe_reg_set_bit(cam, REG_GL_IMASK, GIMSK_CCIC_EN);
	/*
	 * Make sure it's not powered down.
	 */
	cafe_reg_clear_bit(cam, REG_CTRL1, C1_PWRDWN);
	/*
	 * Turn off the enable bit.  It sure should be off anyway,
	 * but it's good to be sure.
	 */
	cafe_reg_clear_bit(cam, REG_CTRL0, C0_ENABLE);
	/*
	 * Mask all interrupts.
	 */
	cafe_reg_write(cam, REG_IRQMASK, 0);
	/*
	 * Clock the sensor appropriately.  Controller clock should
	 * be 48MHz, sensor "typical" value is half that.
	 */
	cafe_reg_write_mask(cam, REG_CLKCTRL, 2, CLK_DIV_MASK);
	spin_unlock_irqrestore(&cam->dev_lock, flags);
}


/*
 * Stop the controller, and don't return until we're really sure that no
 * further DMA is going on.
 */
static void cafe_ctlr_stop_dma(struct cafe_camera *cam)
{
	unsigned long flags;

	/*
	 * Theory: stop the camera controller (whether it is operating
	 * or not).  Delay briefly just in case we race with the SOF
	 * interrupt, then wait until no DMA is active.
	 */
	spin_lock_irqsave(&cam->dev_lock, flags);
	cafe_ctlr_stop(cam);
	spin_unlock_irqrestore(&cam->dev_lock, flags);
	mdelay(1);
	wait_event_timeout(cam->iowait,
			!test_bit(CF_DMA_ACTIVE, &cam->flags), HZ);
	if (test_bit(CF_DMA_ACTIVE, &cam->flags))
		cam_err(cam, "Timeout waiting for DMA to end\n");
		/* This would be bad news - what now? */
	spin_lock_irqsave(&cam->dev_lock, flags);
	cam->state = S_IDLE;
	cafe_ctlr_irq_disable(cam);
	spin_unlock_irqrestore(&cam->dev_lock, flags);
}

/*
 * Power up and down.
 */
static void cafe_ctlr_power_up(struct cafe_camera *cam)
{
	unsigned long flags;

	spin_lock_irqsave(&cam->dev_lock, flags);
	cafe_reg_clear_bit(cam, REG_CTRL1, C1_PWRDWN);
	/*
	 * Part one of the sensor dance: turn the global
	 * GPIO signal on.
	 */
	cafe_reg_write(cam, REG_GL_FCR, GFCR_GPIO_ON);
	cafe_reg_write(cam, REG_GL_GPIOR, GGPIO_OUT|GGPIO_VAL);
	/*
	 * Put the sensor into operational mode (assumes OLPC-style
	 * wiring).  Control 0 is reset - set to 1 to operate.
	 * Control 1 is power down, set to 0 to operate.
	 */
	cafe_reg_write(cam, REG_GPR, GPR_C1EN|GPR_C0EN); /* pwr up, reset */
//	mdelay(1); /* Marvell says 1ms will do it */
	cafe_reg_write(cam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C0);
//	mdelay(1); /* Enough? */
	spin_unlock_irqrestore(&cam->dev_lock, flags);
	msleep(5); /* Just to be sure */
}

static void cafe_ctlr_power_down(struct cafe_camera *cam)
{
	unsigned long flags;

	spin_lock_irqsave(&cam->dev_lock, flags);
	cafe_reg_write(cam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C1);
	cafe_reg_write(cam, REG_GL_FCR, GFCR_GPIO_ON);
	cafe_reg_write(cam, REG_GL_GPIOR, GGPIO_OUT);
	cafe_reg_set_bit(cam, REG_CTRL1, C1_PWRDWN);
	spin_unlock_irqrestore(&cam->dev_lock, flags);
}

/* -------------------------------------------------------------------- */
/*
 * Communications with the sensor.
 */

static int __cafe_cam_cmd(struct cafe_camera *cam, int cmd, void *arg)
{
	struct i2c_client *sc = cam->sensor;
	int ret;

	if (sc == NULL || sc->driver == NULL || sc->driver->command == NULL)
		return -EINVAL;
	ret = sc->driver->command(sc, cmd, arg);
	if (ret == -EPERM) /* Unsupported command */
		return 0;
	return ret;
}

static int __cafe_cam_reset(struct cafe_camera *cam)
{
	int zero = 0;
	return __cafe_cam_cmd(cam, VIDIOC_INT_RESET, &zero);
}

/*
 * We have found the sensor on the i2c.  Let's try to have a
 * conversation.
 */
static int cafe_cam_init(struct cafe_camera *cam)
{
	struct v4l2_chip_ident chip = { V4L2_CHIP_MATCH_I2C_ADDR, 0, 0, 0 };
	int ret;

	mutex_lock(&cam->s_mutex);
	if (cam->state != S_NOTREADY)
		cam_warn(cam, "Cam init with device in funky state %d",
				cam->state);
	ret = __cafe_cam_reset(cam);
	if (ret)
		goto out;
	chip.match_chip = cam->sensor->addr;
	ret = __cafe_cam_cmd(cam, VIDIOC_G_CHIP_IDENT, &chip);
	if (ret)
		goto out;
	cam->sensor_type = chip.ident;
//	if (cam->sensor->addr != OV7xx0_SID) {
	if (cam->sensor_type != V4L2_IDENT_OV7670) {
		cam_err(cam, "Unsupported sensor type %d", cam->sensor->addr);
		ret = -EINVAL;
		goto out;
	}
/* Get/set parameters? */
	ret = 0;
	cam->state = S_IDLE;
  out:
	cafe_ctlr_power_down(cam);
	mutex_unlock(&cam->s_mutex);
	return ret;
}

/*
 * Configure the sensor to match the parameters we have.  Caller should
 * hold s_mutex
 */
static int cafe_cam_set_flip(struct cafe_camera *cam)
{
	struct v4l2_control ctrl;

	memset(&ctrl, 0, sizeof(ctrl));
	ctrl.id = V4L2_CID_VFLIP;
	ctrl.value = flip;
	return __cafe_cam_cmd(cam, VIDIOC_S_CTRL, &ctrl);
}


static int cafe_cam_configure(struct cafe_camera *cam)
{
	struct v4l2_format fmt;
	int ret, zero = 0;

	if (cam->state != S_IDLE)
		return -EINVAL;
	fmt.fmt.pix = cam->pix_format;
	ret = __cafe_cam_cmd(cam, VIDIOC_INT_INIT, &zero);
	if (ret == 0)
		ret = __cafe_cam_cmd(cam, VIDIOC_S_FMT, &fmt);
	/*
	 * OV7670 does weird things if flip is set *before* format...
	 */
	ret += cafe_cam_set_flip(cam);
	return ret;
}

/* -------------------------------------------------------------------- */
/*
 * DMA buffer management.  These functions need s_mutex held.
 */

/* FIXME: this is inefficient as hell, since dma_alloc_coherent just
 * does a get_free_pages() call, and we waste a good chunk of an orderN
 * allocation.  Should try to allocate the whole set in one chunk.
 */
static int cafe_alloc_dma_bufs(struct cafe_camera *cam, int loadtime)
{
	int i;

	cafe_set_config_needed(cam, 1);
	if (loadtime)
		cam->dma_buf_size = dma_buf_size;
	else
		cam->dma_buf_size = cam->pix_format.sizeimage;
	if (n_dma_bufs > 3)
		n_dma_bufs = 3;

	cam->nbufs = 0;
	for (i = 0; i < n_dma_bufs; i++) {
		cam->dma_bufs[i] = dma_alloc_coherent(&cam->pdev->dev,
				cam->dma_buf_size, cam->dma_handles + i,
				GFP_KERNEL);
		if (cam->dma_bufs[i] == NULL) {
			cam_warn(cam, "Failed to allocate DMA buffer\n");
			break;
		}
		/* For debug, remove eventually */
		memset(cam->dma_bufs[i], 0xcc, cam->dma_buf_size);
		(cam->nbufs)++;
	}

	switch (cam->nbufs) {
	case 1:
	    dma_free_coherent(&cam->pdev->dev, cam->dma_buf_size,
			    cam->dma_bufs[0], cam->dma_handles[0]);
	    cam->nbufs = 0;
	case 0:
	    cam_err(cam, "Insufficient DMA buffers, cannot operate\n");
	    return -ENOMEM;

	case 2:
	    if (n_dma_bufs > 2)
		    cam_warn(cam, "Will limp along with only 2 buffers\n");
	    break;
	}
	return 0;
}

static void cafe_free_dma_bufs(struct cafe_camera *cam)
{
	int i;

	for (i = 0; i < cam->nbufs; i++) {
		dma_free_coherent(&cam->pdev->dev, cam->dma_buf_size,
				cam->dma_bufs[i], cam->dma_handles[i]);
		cam->dma_bufs[i] = NULL;
	}
	cam->nbufs = 0;
}





/* ----------------------------------------------------------------------- */
/*
 * Here starts the V4L2 interface code.
 */

/*
 * Read an image from the device.
 */
static ssize_t cafe_deliver_buffer(struct cafe_camera *cam,
		char __user *buffer, size_t len, loff_t *pos)
{
	int bufno;
	unsigned long flags;

	spin_lock_irqsave(&cam->dev_lock, flags);
	if (cam->next_buf < 0) {
		cam_err(cam, "deliver_buffer: No next buffer\n");
		spin_unlock_irqrestore(&cam->dev_lock, flags);
		return -EIO;
	}
	bufno = cam->next_buf;
	clear_bit(bufno, &cam->flags);
	if (++(cam->next_buf) >= cam->nbufs)
		cam->next_buf = 0;
	if (! test_bit(cam->next_buf, &cam->flags))
		cam->next_buf = -1;
	cam->specframes = 0;
	spin_unlock_irqrestore(&cam->dev_lock, flags);

	if (len > cam->pix_format.sizeimage)
		len = cam->pix_format.sizeimage;
	if (copy_to_user(buffer, cam->dma_bufs[bufno], len))
		return -EFAULT;
	(*pos) += len;
	return len;
}

/*
 * Get everything ready, and start grabbing frames.
 */
static int cafe_read_setup(struct cafe_camera *cam, enum cafe_state state)
{
	int ret;
	unsigned long flags;

	/*
	 * Configuration.  If we still don't have DMA buffers,
	 * make one last, desperate attempt.
	 */
	if (cam->nbufs == 0)
		if (cafe_alloc_dma_bufs(cam, 0))
			return -ENOMEM;

	if (cafe_needs_config(cam)) {
		cafe_cam_configure(cam);
		ret = cafe_ctlr_configure(cam);
		if (ret)
			return ret;
	}

	/*
	 * Turn it loose.
	 */
	spin_lock_irqsave(&cam->dev_lock, flags);
	cafe_reset_buffers(cam);
	cafe_ctlr_irq_enable(cam);
	cam->state = state;
	cafe_ctlr_start(cam);
	spin_unlock_irqrestore(&cam->dev_lock, flags);
	return 0;
}


static ssize_t cafe_v4l_read(struct file *filp,
		char __user *buffer, size_t len, loff_t *pos)
{
	struct cafe_camera *cam = filp->private_data;
	int ret = 0;

	/*
	 * Perhaps we're in speculative read mode and already
	 * have data?
	 */
	mutex_lock(&cam->s_mutex);
	if (cam->state == S_SPECREAD) {
		if (cam->next_buf >= 0) {
			ret = cafe_deliver_buffer(cam, buffer, len, pos);
			if (ret != 0)
				goto out_unlock;
		}
	} else if (cam->state == S_FLAKED || cam->state == S_NOTREADY) {
		ret = -EIO;
		goto out_unlock;
	} else if (cam->state != S_IDLE) {
		ret = -EBUSY;
		goto out_unlock;
	}

	/*
	 * v4l2: multiple processes can open the device, but only
	 * one gets to grab data from it.
	 */
	if (cam->owner && cam->owner != filp) {
		ret = -EBUSY;
		goto out_unlock;
	}
	cam->owner = filp;

	/*
	 * Do setup if need be.
	 */
	if (cam->state != S_SPECREAD) {
		ret = cafe_read_setup(cam, S_SINGLEREAD);
		if (ret)
			goto out_unlock;
	}
	/*
	 * Wait for something to happen.  This should probably
	 * be interruptible (FIXME).
	 */
	wait_event_timeout(cam->iowait, cam->next_buf >= 0, HZ);
	if (cam->next_buf < 0) {
		cam_err(cam, "read() operation timed out\n");
		cafe_ctlr_stop_dma(cam);
		ret = -EIO;
		goto out_unlock;
	}
	/*
	 * Give them their data and we should be done.
	 */
	ret = cafe_deliver_buffer(cam, buffer, len, pos);

  out_unlock:
	mutex_unlock(&cam->s_mutex);
	return ret;
}








/*
 * Streaming I/O support.
 */



static int cafe_vidioc_streamon(struct file *filp, void *priv,
		enum v4l2_buf_type type)
{
	struct cafe_camera *cam = filp->private_data;
	int ret = -EINVAL;

	if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		goto out;
	mutex_lock(&cam->s_mutex);
	if (cam->state != S_IDLE || cam->n_sbufs == 0)
		goto out_unlock;

	cam->sequence = 0;
	ret = cafe_read_setup(cam, S_STREAMING);

  out_unlock:
	mutex_unlock(&cam->s_mutex);
  out:
	return ret;
}


static int cafe_vidioc_streamoff(struct file *filp, void *priv,
		enum v4l2_buf_type type)
{
	struct cafe_camera *cam = filp->private_data;
	int ret = -EINVAL;

	if (type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
		goto out;