--- /dev/null
+/*
+ * Driver for the VIA Chrome integrated camera controller.
+ *
+ * Copyright 2009,2010 Jonathan Corbet <corbet@lwn.net>
+ * Distributable under the terms of the GNU General Public License, version 2
+ *
+ * This work was supported by the One Laptop Per Child project
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/videodev2.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-ioctl.h>
+#include <media/v4l2-chip-ident.h>
+#include <media/videobuf-dma-sg.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/pm_qos_params.h>
+#include <linux/via-core.h>
+#include <linux/via-gpio.h>
+#include <linux/via_i2c.h>
+
+#include "via-camera.h"
+
+MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
+MODULE_DESCRIPTION("VIA framebuffer-based camera controller driver");
+MODULE_LICENSE("GPL");
+
+static int flip_image;
+module_param(flip_image, bool, 0444);
+MODULE_PARM_DESC(flip_image,
+ "If set, the sensor will be instructed to flip the image "
+ "vertically.");
+
+#ifdef CONFIG_OLPC_XO_1_5
+static int override_serial;
+module_param(override_serial, bool, 0444);
+MODULE_PARM_DESC(override_serial,
+ "The camera driver will normally refuse to load if "
+ "the XO 1.5 serial port is enabled. Set this option "
+ "to force the issue.");
+#endif
+
+/*
+ * Basic window sizes.
+ */
+#define VGA_WIDTH 640
+#define VGA_HEIGHT 480
+#define QCIF_WIDTH 176
+#define QCIF_HEIGHT 144
+
+/*
+ * The structure describing our camera.
+ */
+enum viacam_opstate { S_IDLE = 0, S_RUNNING = 1 };
+
+struct via_camera {
+ struct v4l2_device v4l2_dev;
+ struct video_device vdev;
+ struct v4l2_subdev *sensor;
+ struct platform_device *platdev;
+ struct viafb_dev *viadev;
+ struct mutex lock;
+ enum viacam_opstate opstate;
+ unsigned long flags;
+ struct pm_qos_request_list qos_request;
+ /*
+ * GPIO info for power/reset management
+ */
+ int power_gpio;
+ int reset_gpio;
+ /*
+ * I/O memory stuff.
+ */
+ void __iomem *mmio; /* Where the registers live */
+ void __iomem *fbmem; /* Frame buffer memory */
+ u32 fb_offset; /* Reserved memory offset (FB) */
+ /*
+ * Capture buffers and related. The controller supports
+ * up to three, so that's what we have here. These buffers
+ * live in frame buffer memory, so we don't call them "DMA".
+ */
+ unsigned int cb_offsets[3]; /* offsets into fb mem */
+ u8 *cb_addrs[3]; /* Kernel-space addresses */
+ int n_cap_bufs; /* How many are we using? */
+ int next_buf;
+ struct videobuf_queue vb_queue;
+ struct list_head buffer_queue; /* prot. by reg_lock */
+ /*
+ * User tracking.
+ */
+ int users;
+ struct file *owner;
+ /*
+ * Video format information. sensor_format is kept in a form
+ * that we can use to pass to the sensor. We always run the
+ * sensor in VGA resolution, though, and let the controller
+ * downscale things if need be. So we keep the "real*
+ * dimensions separately.
+ */
+ struct v4l2_pix_format sensor_format;
+ struct v4l2_pix_format user_format;
+ enum v4l2_mbus_pixelcode mbus_code;
+};
+
+/*
+ * Yes, this is a hack, but there's only going to be one of these
+ * on any system we know of.
+ */
+static struct via_camera *via_cam_info;
+
+/*
+ * Flag values, manipulated with bitops
+ */
+#define CF_DMA_ACTIVE 0 /* A frame is incoming */
+#define CF_CONFIG_NEEDED 1 /* Must configure hardware */
+
+
+/*
+ * Nasty ugly v4l2 boilerplate.
+ */
+#define sensor_call(cam, optype, func, args...) \
+ v4l2_subdev_call(cam->sensor, optype, func, ##args)
+
+/*
+ * Debugging and related.
+ */
+#define cam_err(cam, fmt, arg...) \
+ dev_err(&(cam)->platdev->dev, fmt, ##arg);
+#define cam_warn(cam, fmt, arg...) \
+ dev_warn(&(cam)->platdev->dev, fmt, ##arg);
+#define cam_dbg(cam, fmt, arg...) \
+ dev_dbg(&(cam)->platdev->dev, fmt, ##arg);
+
+/*
+ * Format handling. This is ripped almost directly from Hans's changes
+ * to cafe_ccic.c. It's a little unfortunate; until this change, we
+ * didn't need to know anything about the format except its byte depth;
+ * now this information must be managed at this level too.
+ */
+static struct via_format {
+ __u8 *desc;
+ __u32 pixelformat;
+ int bpp; /* Bytes per pixel */
+ enum v4l2_mbus_pixelcode mbus_code;
+} via_formats[] = {
+ {
+ .desc = "YUYV 4:2:2",
+ .pixelformat = V4L2_PIX_FMT_YUYV,
+ .mbus_code = V4L2_MBUS_FMT_YUYV8_2X8,
+ .bpp = 2,
+ },
+ {
+ .desc = "RGB 565",
+ .pixelformat = V4L2_PIX_FMT_RGB565,
+ .mbus_code = V4L2_MBUS_FMT_RGB565_2X8_LE,
+ .bpp = 2,
+ },
+ /* RGB444 and Bayer should be doable, but have never been
+ tested with this driver. */
+};
+#define N_VIA_FMTS ARRAY_SIZE(via_formats)
+
+static struct via_format *via_find_format(u32 pixelformat)
+{
+ unsigned i;
+
+ for (i = 0; i < N_VIA_FMTS; i++)
+ if (via_formats[i].pixelformat == pixelformat)
+ return via_formats + i;
+ /* Not found? Then return the first format. */
+ return via_formats;
+}
+
+
+/*--------------------------------------------------------------------------*/
+/*
+ * Sensor power/reset management. This piece is OLPC-specific for
+ * sure; other configurations will have things connected differently.
+ */
+static int via_sensor_power_setup(struct via_camera *cam)
+{
+ int ret;
+
+ cam->power_gpio = viafb_gpio_lookup("VGPIO3");
+ cam->reset_gpio = viafb_gpio_lookup("VGPIO2");
+ if (cam->power_gpio < 0 || cam->reset_gpio < 0) {
+ dev_err(&cam->platdev->dev, "Unable to find GPIO lines\n");
+ return -EINVAL;
+ }
+ ret = gpio_request(cam->power_gpio, "viafb-camera");
+ if (ret) {
+ dev_err(&cam->platdev->dev, "Unable to request power GPIO\n");
+ return ret;
+ }
+ ret = gpio_request(cam->reset_gpio, "viafb-camera");
+ if (ret) {
+ dev_err(&cam->platdev->dev, "Unable to request reset GPIO\n");
+ gpio_free(cam->power_gpio);
+ return ret;
+ }
+ gpio_direction_output(cam->power_gpio, 0);
+ gpio_direction_output(cam->reset_gpio, 0);
+ return 0;
+}
+
+/*
+ * Power up the sensor and perform the reset dance.
+ */
+static void via_sensor_power_up(struct via_camera *cam)
+{
+ gpio_set_value(cam->power_gpio, 1);
+ gpio_set_value(cam->reset_gpio, 0);
+ msleep(20); /* Probably excessive */
+ gpio_set_value(cam->reset_gpio, 1);
+ msleep(20);
+}
+
+static void via_sensor_power_down(struct via_camera *cam)
+{
+ gpio_set_value(cam->power_gpio, 0);
+ gpio_set_value(cam->reset_gpio, 0);
+}
+
+
+static void via_sensor_power_release(struct via_camera *cam)
+{
+ via_sensor_power_down(cam);
+ gpio_free(cam->power_gpio);
+ gpio_free(cam->reset_gpio);
+}
+
+/* --------------------------------------------------------------------------*/
+/* Sensor ops */
+
+/*
+ * Manage the ov7670 "flip" bit, which needs special help.
+ */
+static int viacam_set_flip(struct via_camera *cam)
+{
+ struct v4l2_control ctrl;
+
+ memset(&ctrl, 0, sizeof(ctrl));
+ ctrl.id = V4L2_CID_VFLIP;
+ ctrl.value = flip_image;
+ return sensor_call(cam, core, s_ctrl, &ctrl);
+}
+
+/*
+ * Configure the sensor. It's up to the caller to ensure
+ * that the camera is in the correct operating state.
+ */
+static int viacam_configure_sensor(struct via_camera *cam)
+{
+ struct v4l2_mbus_framefmt mbus_fmt;
+ int ret;
+
+ v4l2_fill_mbus_format(&mbus_fmt, &cam->sensor_format, cam->mbus_code);
+ ret = sensor_call(cam, core, init, 0);
+ if (ret == 0)
+ ret = sensor_call(cam, video, s_mbus_fmt, &mbus_fmt);
+ /*
+ * OV7670 does weird things if flip is set *before* format...
+ */
+ if (ret == 0)
+ ret = viacam_set_flip(cam);
+ return ret;
+}
+
+
+
+/* --------------------------------------------------------------------------*/
+/*
+ * Some simple register accessors; they assume that the lock is held.
+ *
+ * Should we want to support the second capture engine, we could
+ * hide the register difference by adding 0x1000 to registers in the
+ * 0x300-350 range.
+ */
+static inline void viacam_write_reg(struct via_camera *cam,
+ int reg, int value)
+{
+ iowrite32(value, cam->mmio + reg);
+}
+
+static inline int viacam_read_reg(struct via_camera *cam, int reg)
+{
+ return ioread32(cam->mmio + reg);
+}
+
+static inline void viacam_write_reg_mask(struct via_camera *cam,
+ int reg, int value, int mask)
+{
+ int tmp = viacam_read_reg(cam, reg);
+
+ tmp = (tmp & ~mask) | (value & mask);
+ viacam_write_reg(cam, reg, tmp);
+}
+
+
+/* --------------------------------------------------------------------------*/
+/* Interrupt management and handling */
+
+static irqreturn_t viacam_quick_irq(int irq, void *data)
+{
+ struct via_camera *cam = data;
+ irqreturn_t ret = IRQ_NONE;
+ int icv;
+
+ /*
+ * All we do here is to clear the interrupts and tell
+ * the handler thread to wake up.
+ */
+ spin_lock(&cam->viadev->reg_lock);
+ icv = viacam_read_reg(cam, VCR_INTCTRL);
+ if (icv & VCR_IC_EAV) {
+ icv |= VCR_IC_EAV|VCR_IC_EVBI|VCR_IC_FFULL;
+ viacam_write_reg(cam, VCR_INTCTRL, icv);
+ ret = IRQ_WAKE_THREAD;
+ }
+ spin_unlock(&cam->viadev->reg_lock);
+ return ret;
+}
+
+/*
+ * Find the next videobuf buffer which has somebody waiting on it.
+ */
+static struct videobuf_buffer *viacam_next_buffer(struct via_camera *cam)
+{
+ unsigned long flags;
+ struct videobuf_buffer *buf = NULL;
+
+ spin_lock_irqsave(&cam->viadev->reg_lock, flags);
+ if (cam->opstate != S_RUNNING)
+ goto out;
+ if (list_empty(&cam->buffer_queue))
+ goto out;
+ buf = list_entry(cam->buffer_queue.next, struct videobuf_buffer, queue);
+ if (!waitqueue_active(&buf->done)) {/* Nobody waiting */
+ buf = NULL;
+ goto out;
+ }
+ list_del(&buf->queue);
+ buf->state = VIDEOBUF_ACTIVE;
+out:
+ spin_unlock_irqrestore(&cam->viadev->reg_lock, flags);
+ return buf;
+}
+
+/*
+ * The threaded IRQ handler.
+ */
+static irqreturn_t viacam_irq(int irq, void *data)
+{
+ int bufn;
+ struct videobuf_buffer *vb;
+ struct via_camera *cam = data;
+ struct videobuf_dmabuf *vdma;
+
+ /*
+ * If there is no place to put the data frame, don't bother
+ * with anything else.
+ */
+ vb = viacam_next_buffer(cam);
+ if (vb == NULL)
+ goto done;
+ /*
+ * Figure out which buffer we just completed.
+ */
+ bufn = (viacam_read_reg(cam, VCR_INTCTRL) & VCR_IC_ACTBUF) >> 3;
+ bufn -= 1;
+ if (bufn < 0)
+ bufn = cam->n_cap_bufs - 1;
+ /*
+ * Copy over the data and let any waiters know.
+ */
+ vdma = videobuf_to_dma(vb);
+ viafb_dma_copy_out_sg(cam->cb_offsets[bufn], vdma->sglist, vdma->sglen);
+ vb->state = VIDEOBUF_DONE;
+ vb->size = cam->user_format.sizeimage;
+ wake_up(&vb->done);
+done:
+ return IRQ_HANDLED;
+}
+
+
+/*
+ * These functions must mess around with the general interrupt
+ * control register, which is relevant to much more than just the
+ * camera. Nothing else uses interrupts, though, as of this writing.
+ * Should that situation change, we'll have to improve support at
+ * the via-core level.
+ */
+static void viacam_int_enable(struct via_camera *cam)
+{
+ viacam_write_reg(cam, VCR_INTCTRL,
+ VCR_IC_INTEN|VCR_IC_EAV|VCR_IC_EVBI|VCR_IC_FFULL);
+ viafb_irq_enable(VDE_I_C0AVEN);
+}
+
+static void viacam_int_disable(struct via_camera *cam)
+{
+ viafb_irq_disable(VDE_I_C0AVEN);
+ viacam_write_reg(cam, VCR_INTCTRL, 0);
+}
+
+
+
+/* --------------------------------------------------------------------------*/
+/* Controller operations */
+
+/*
+ * Set up our capture buffers in framebuffer memory.
+ */
+static int viacam_ctlr_cbufs(struct via_camera *cam)
+{
+ int nbuf = cam->viadev->camera_fbmem_size/cam->sensor_format.sizeimage;
+ int i;
+ unsigned int offset;
+
+ /*
+ * See how many buffers we can work with.
+ */
+ if (nbuf >= 3) {
+ cam->n_cap_bufs = 3;
+ viacam_write_reg_mask(cam, VCR_CAPINTC, VCR_CI_3BUFS,
+ VCR_CI_3BUFS);
+ } else if (nbuf == 2) {
+ cam->n_cap_bufs = 2;
+ viacam_write_reg_mask(cam, VCR_CAPINTC, 0, VCR_CI_3BUFS);
+ } else {
+ cam_warn(cam, "Insufficient frame buffer memory\n");
+ return -ENOMEM;
+ }
+ /*
+ * Set them up.
+ */
+ offset = cam->fb_offset;
+ for (i = 0; i < cam->n_cap_bufs; i++) {
+ cam->cb_offsets[i] = offset;
+ cam->cb_addrs[i] = cam->fbmem + offset;
+ viacam_write_reg(cam, VCR_VBUF1 + i*4, offset & VCR_VBUF_MASK);
+ offset += cam->sensor_format.sizeimage;
+ }
+ return 0;
+}
+
+/*
+ * Set the scaling register for downscaling the image.
+ *
+ * This register works like this... Vertical scaling is enabled
+ * by bit 26; if that bit is set, downscaling is controlled by the
+ * value in bits 16:25. Those bits are divided by 1024 to get
+ * the scaling factor; setting just bit 25 thus cuts the height
+ * in half.
+ *
+ * Horizontal scaling works about the same, but it's enabled by
+ * bit 11, with bits 0:10 giving the numerator of a fraction
+ * (over 2048) for the scaling value.
+ *
+ * This function is naive in that, if the user departs from
+ * the 3x4 VGA scaling factor, the image will distort. We
+ * could work around that if it really seemed important.
+ */
+static void viacam_set_scale(struct via_camera *cam)
+{
+ unsigned int avscale;
+ int sf;
+
+ if (cam->user_format.width == VGA_WIDTH)
+ avscale = 0;
+ else {
+ sf = (cam->user_format.width*2048)/VGA_WIDTH;
+ avscale = VCR_AVS_HEN | sf;
+ }
+ if (cam->user_format.height < VGA_HEIGHT) {
+ sf = (1024*cam->user_format.height)/VGA_HEIGHT;
+ avscale |= VCR_AVS_VEN | (sf << 16);
+ }
+ viacam_write_reg(cam, VCR_AVSCALE, avscale);
+}
+
+
+/*
+ * Configure image-related information into the capture engine.
+ */
+static void viacam_ctlr_image(struct via_camera *cam)
+{
+ int cicreg;
+
+ /*
+ * Disable clock before messing with stuff - from the via
+ * sample driver.
+ */
+ viacam_write_reg(cam, VCR_CAPINTC, ~(VCR_CI_ENABLE|VCR_CI_CLKEN));
+ /*
+ * Set up the controller for VGA resolution, modulo magic
+ * offsets from the via sample driver.
+ */
+ viacam_write_reg(cam, VCR_HORRANGE, 0x06200120);
+ viacam_write_reg(cam, VCR_VERTRANGE, 0x01de0000);
+ viacam_set_scale(cam);
+ /*
+ * Image size info.
+ */
+ viacam_write_reg(cam, VCR_MAXDATA,
+ (cam->sensor_format.height << 16) |
+ (cam->sensor_format.bytesperline >> 3));
+ viacam_write_reg(cam, VCR_MAXVBI, 0);
+ viacam_write_reg(cam, VCR_VSTRIDE,
+ cam->user_format.bytesperline & VCR_VS_STRIDE);
+ /*
+ * Set up the capture interface control register,
+ * everything but the "go" bit.
+ *
+ * The FIFO threshold is a bit of a magic number; 8 is what
+ * VIA's sample code uses.
+ */
+ cicreg = VCR_CI_CLKEN |
+ 0x08000000 | /* FIFO threshold */
+ VCR_CI_FLDINV | /* OLPC-specific? */
+ VCR_CI_VREFINV | /* OLPC-specific? */
+ VCR_CI_DIBOTH | /* Capture both fields */
+ VCR_CI_CCIR601_8;
+ if (cam->n_cap_bufs == 3)
+ cicreg |= VCR_CI_3BUFS;
+ /*
+ * YUV formats need different byte swapping than RGB.
+ */
+ if (cam->user_format.pixelformat == V4L2_PIX_FMT_YUYV)
+ cicreg |= VCR_CI_YUYV;
+ else
+ cicreg |= VCR_CI_UYVY;
+ viacam_write_reg(cam, VCR_CAPINTC, cicreg);
+}
+
+
+static int viacam_config_controller(struct via_camera *cam)
+{
+ int ret;
+ unsigned long flags;
+
+ spin_lock_irqsave(&cam->viadev->reg_lock, flags);
+ ret = viacam_ctlr_cbufs(cam);
+ if (!ret)
+ viacam_ctlr_image(cam);
+ spin_unlock_irqrestore(&cam->viadev->reg_lock, flags);
+ clear_bit(CF_CONFIG_NEEDED, &cam->flags);
+ return ret;
+}
+
+/*
+ * Make it start grabbing data.
+ */
+static void viacam_start_engine(struct via_camera *cam)
+{
+ spin_lock_irq(&cam->viadev->reg_lock);
+ cam->next_buf = 0;
+ viacam_write_reg_mask(cam, VCR_CAPINTC, VCR_CI_ENABLE, VCR_CI_ENABLE);
+ viacam_int_enable(cam);
+ (void) viacam_read_reg(cam, VCR_CAPINTC); /* Force post */
+ cam->opstate = S_RUNNING;
+ spin_unlock_irq(&cam->viadev->reg_lock);
+}
+
+
+static void viacam_stop_engine(struct via_camera *cam)
+{
+ spin_lock_irq(&cam->viadev->reg_lock);
+ viacam_int_disable(cam);
+ viacam_write_reg_mask(cam, VCR_CAPINTC, 0, VCR_CI_ENABLE);
+ (void) viacam_read_reg(cam, VCR_CAPINTC); /* Force post */
+ cam->opstate = S_IDLE;
+ spin_unlock_irq(&cam->viadev->reg_lock);
+}
+
+
+/* --------------------------------------------------------------------------*/
+/* Videobuf callback ops */
+
+/*
+ * buffer_setup. The purpose of this one would appear to be to tell
+ * videobuf how big a single image is. It's also evidently up to us
+ * to put some sort of limit on the maximum number of buffers allowed.
+ */
+static int viacam_vb_buf_setup(struct videobuf_queue *q,
+ unsigned int *count, unsigned int *size)
+{
+ struct via_camera *cam = q->priv_data;
+
+ *size = cam->user_format.sizeimage;
+ if (*count == 0 || *count > 6) /* Arbitrary number */
+ *count = 6;
+ return 0;
+}
+
+/*
+ * Prepare a buffer.
+ */
+static int viacam_vb_buf_prepare(struct videobuf_queue *q,
+ struct videobuf_buffer *vb, enum v4l2_field field)
+{
+ struct via_camera *cam = q->priv_data;
+
+ vb->size = cam->user_format.sizeimage;
+ vb->width = cam->user_format.width; /* bytesperline???? */
+ vb->height = cam->user_format.height;
+ vb->field = field;
+ if (vb->state == VIDEOBUF_NEEDS_INIT) {
+ int ret = videobuf_iolock(q, vb, NULL);
+ if (ret)
+ return ret;
+ }
+ vb->state = VIDEOBUF_PREPARED;
+ return 0;
+}
+
+/*
+ * We've got a buffer to put data into.
+ *
+ * FIXME: check for a running engine and valid buffers?
+ */
+static void viacam_vb_buf_queue(struct videobuf_queue *q,
+ struct videobuf_buffer *vb)
+{
+ struct via_camera *cam = q->priv_data;
+
+ /*
+ * Note that videobuf holds the lock when it calls
+ * us, so we need not (indeed, cannot) take it here.
+ */
+ vb->state = VIDEOBUF_QUEUED;
+ list_add_tail(&vb->queue, &cam->buffer_queue);
+}
+
+/*
+ * Free a buffer.
+ */
+static void viacam_vb_buf_release(struct videobuf_queue *q,
+ struct videobuf_buffer *vb)
+{
+ struct via_camera *cam = q->priv_data;
+
+ videobuf_dma_unmap(&cam->platdev->dev, videobuf_to_dma(vb));
+ videobuf_dma_free(videobuf_to_dma(vb));
+ vb->state = VIDEOBUF_NEEDS_INIT;
+}
+
+static const struct videobuf_queue_ops viacam_vb_ops = {
+ .buf_setup = viacam_vb_buf_setup,
+ .buf_prepare = viacam_vb_buf_prepare,
+ .buf_queue = viacam_vb_buf_queue,
+ .buf_release = viacam_vb_buf_release,
+};
+
+/* --------------------------------------------------------------------------*/
+/* File operations */
+
+static int viacam_open(struct file *filp)
+{
+ struct via_camera *cam = video_drvdata(filp);
+
+ filp->private_data = cam;
+ /*
+ * Note the new user. If this is the first one, we'll also
+ * need to power up the sensor.
+ */
+ mutex_lock(&cam->lock);
+ if (cam->users == 0) {
+ int ret = viafb_request_dma();
+
+ if (ret) {
+ mutex_unlock(&cam->lock);
+ return ret;
+ }
+ via_sensor_power_up(cam);
+ set_bit(CF_CONFIG_NEEDED, &cam->flags);
+ /*
+ * Hook into videobuf. Evidently this cannot fail.
+ */
+ videobuf_queue_sg_init(&cam->vb_queue, &viacam_vb_ops,
+ &cam->platdev->dev, &cam->viadev->reg_lock,
+ V4L2_BUF_TYPE_VIDEO_CAPTURE, V4L2_FIELD_NONE,
+ sizeof(struct videobuf_buffer), cam, NULL);
+ }
+ (cam->users)++;
+ mutex_unlock(&cam->lock);
+ return 0;
+}
+
+static int viacam_release(struct file *filp)
+{
+ struct via_camera *cam = video_drvdata(filp);
+
+ mutex_lock(&cam->lock);
+ (cam->users)--;
+ /*
+ * If the "owner" is closing, shut down any ongoing
+ * operations.
+ */
+ if (filp == cam->owner) {
+ videobuf_stop(&cam->vb_queue);
+ /*
+ * We don't hold the spinlock here, but, if release()
+ * is being called by the owner, nobody else will
+ * be changing the state. And an extra stop would
+ * not hurt anyway.
+ */
+ if (cam->opstate != S_IDLE)
+ viacam_stop_engine(cam);
+ cam->owner = NULL;
+ }
+ /*
+ * Last one out needs to turn out the lights.
+ */
+ if (cam->users == 0) {
+ videobuf_mmap_free(&cam->vb_queue);
+ via_sensor_power_down(cam);
+ viafb_release_dma();
+ }
+ mutex_unlock(&cam->lock);
+ return 0;
+}
+
+/*
+ * Read a frame from the device.
+ */
+static ssize_t viacam_read(struct file *filp, char __user *buffer,
+ size_t len, loff_t *pos)
+{
+ struct via_camera *cam = video_drvdata(filp);
+ int ret;
+
+ mutex_lock(&cam->lock);
+ /*
+ * Enforce the V4l2 "only one owner gets to read data" rule.
+ */
+ if (cam->owner && cam->owner != filp) {
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+ cam->owner = filp;
+ /*
+ * Do we need to configure the hardware?
+ */
+ if (test_bit(CF_CONFIG_NEEDED, &cam->flags)) {
+ ret = viacam_configure_sensor(cam);
+ if (!ret)
+ ret = viacam_config_controller(cam);
+ if (ret)
+ goto out_unlock;
+ }
+ /*
+ * Fire up the capture engine, then have videobuf do
+ * the heavy lifting. Someday it would be good to avoid
+ * stopping and restarting the engine each time.
+ */
+ INIT_LIST_HEAD(&cam->buffer_queue);
+ viacam_start_engine(cam);
+ ret = videobuf_read_stream(&cam->vb_queue, buffer, len, pos, 0,
+ filp->f_flags & O_NONBLOCK);
+ viacam_stop_engine(cam);
+ /* videobuf_stop() ?? */
+
+out_unlock:
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+
+static unsigned int viacam_poll(struct file *filp, struct poll_table_struct *pt)
+{
+ struct via_camera *cam = video_drvdata(filp);
+
+ return videobuf_poll_stream(filp, &cam->vb_queue, pt);
+}
+
+
+static int viacam_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+ struct via_camera *cam = video_drvdata(filp);
+
+ return videobuf_mmap_mapper(&cam->vb_queue, vma);
+}
+
+
+
+static const struct v4l2_file_operations viacam_fops = {
+ .owner = THIS_MODULE,
+ .open = viacam_open,
+ .release = viacam_release,
+ .read = viacam_read,
+ .poll = viacam_poll,
+ .mmap = viacam_mmap,
+ .unlocked_ioctl = video_ioctl2,
+};
+
+/*----------------------------------------------------------------------------*/
+/*
+ * The long list of v4l2 ioctl ops
+ */
+
+static int viacam_g_chip_ident(struct file *file, void *priv,
+ struct v4l2_dbg_chip_ident *ident)
+{
+ struct via_camera *cam = priv;
+
+ ident->ident = V4L2_IDENT_NONE;
+ ident->revision = 0;
+ if (v4l2_chip_match_host(&ident->match)) {
+ ident->ident = V4L2_IDENT_VIA_VX855;
+ return 0;
+ }
+ return sensor_call(cam, core, g_chip_ident, ident);
+}
+
+/*
+ * Control ops are passed through to the sensor.
+ */
+static int viacam_queryctrl(struct file *filp, void *priv,
+ struct v4l2_queryctrl *qc)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = sensor_call(cam, core, queryctrl, qc);
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+
+static int viacam_g_ctrl(struct file *filp, void *priv,
+ struct v4l2_control *ctrl)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = sensor_call(cam, core, g_ctrl, ctrl);
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+
+static int viacam_s_ctrl(struct file *filp, void *priv,
+ struct v4l2_control *ctrl)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = sensor_call(cam, core, s_ctrl, ctrl);
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+/*
+ * Only one input.
+ */
+static int viacam_enum_input(struct file *filp, void *priv,
+ struct v4l2_input *input)
+{
+ if (input->index != 0)
+ return -EINVAL;
+
+ input->type = V4L2_INPUT_TYPE_CAMERA;
+ input->std = V4L2_STD_ALL; /* Not sure what should go here */
+ strcpy(input->name, "Camera");
+ return 0;
+}
+
+static int viacam_g_input(struct file *filp, void *priv, unsigned int *i)
+{
+ *i = 0;
+ return 0;
+}
+
+static int viacam_s_input(struct file *filp, void *priv, unsigned int i)
+{
+ if (i != 0)
+ return -EINVAL;
+ return 0;
+}
+
+static int viacam_s_std(struct file *filp, void *priv, v4l2_std_id *std)
+{
+ return 0;
+}
+
+/*
+ * Video format stuff. Here is our default format until
+ * user space messes with things.
+ */
+static const struct v4l2_pix_format viacam_def_pix_format = {
+ .width = VGA_WIDTH,
+ .height = VGA_HEIGHT,
+ .pixelformat = V4L2_PIX_FMT_YUYV,
+ .field = V4L2_FIELD_NONE,
+ .bytesperline = VGA_WIDTH * 2,
+ .sizeimage = VGA_WIDTH * VGA_HEIGHT * 2,
+};
+
+static const enum v4l2_mbus_pixelcode via_def_mbus_code = V4L2_MBUS_FMT_YUYV8_2X8;
+
+static int viacam_enum_fmt_vid_cap(struct file *filp, void *priv,
+ struct v4l2_fmtdesc *fmt)
+{
+ if (fmt->index >= N_VIA_FMTS)
+ return -EINVAL;
+ strlcpy(fmt->description, via_formats[fmt->index].desc,
+ sizeof(fmt->description));
+ fmt->pixelformat = via_formats[fmt->index].pixelformat;
+ return 0;
+}
+
+/*
+ * Figure out proper image dimensions, but always force the
+ * sensor to VGA.
+ */
+static void viacam_fmt_pre(struct v4l2_pix_format *userfmt,
+ struct v4l2_pix_format *sensorfmt)
+{
+ *sensorfmt = *userfmt;
+ if (userfmt->width < QCIF_WIDTH || userfmt->height < QCIF_HEIGHT) {
+ userfmt->width = QCIF_WIDTH;
+ userfmt->height = QCIF_HEIGHT;
+ }
+ if (userfmt->width > VGA_WIDTH || userfmt->height > VGA_HEIGHT) {
+ userfmt->width = VGA_WIDTH;
+ userfmt->height = VGA_HEIGHT;
+ }
+ sensorfmt->width = VGA_WIDTH;
+ sensorfmt->height = VGA_HEIGHT;
+}
+
+static void viacam_fmt_post(struct v4l2_pix_format *userfmt,
+ struct v4l2_pix_format *sensorfmt)
+{
+ struct via_format *f = via_find_format(userfmt->pixelformat);
+
+ sensorfmt->bytesperline = sensorfmt->width * f->bpp;
+ sensorfmt->sizeimage = sensorfmt->height * sensorfmt->bytesperline;
+ userfmt->pixelformat = sensorfmt->pixelformat;
+ userfmt->field = sensorfmt->field;
+ userfmt->bytesperline = 2 * userfmt->width;
+ userfmt->sizeimage = userfmt->bytesperline * userfmt->height;
+}
+
+
+/*
+ * The real work of figuring out a workable format.
+ */
+static int viacam_do_try_fmt(struct via_camera *cam,
+ struct v4l2_pix_format *upix, struct v4l2_pix_format *spix)
+{
+ int ret;
+ struct v4l2_mbus_framefmt mbus_fmt;
+ struct via_format *f = via_find_format(upix->pixelformat);
+
+ upix->pixelformat = f->pixelformat;
+ viacam_fmt_pre(upix, spix);
+ v4l2_fill_mbus_format(&mbus_fmt, upix, f->mbus_code);
+ ret = sensor_call(cam, video, try_mbus_fmt, &mbus_fmt);
+ v4l2_fill_pix_format(spix, &mbus_fmt);
+ viacam_fmt_post(upix, spix);
+ return ret;
+}
+
+
+
+static int viacam_try_fmt_vid_cap(struct file *filp, void *priv,
+ struct v4l2_format *fmt)
+{
+ struct via_camera *cam = priv;
+ struct v4l2_format sfmt;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = viacam_do_try_fmt(cam, &fmt->fmt.pix, &sfmt.fmt.pix);
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+
+static int viacam_g_fmt_vid_cap(struct file *filp, void *priv,
+ struct v4l2_format *fmt)
+{
+ struct via_camera *cam = priv;
+
+ mutex_lock(&cam->lock);
+ fmt->fmt.pix = cam->user_format;
+ mutex_unlock(&cam->lock);
+ return 0;
+}
+
+static int viacam_s_fmt_vid_cap(struct file *filp, void *priv,
+ struct v4l2_format *fmt)
+{
+ struct via_camera *cam = priv;
+ int ret;
+ struct v4l2_format sfmt;
+ struct via_format *f = via_find_format(fmt->fmt.pix.pixelformat);
+
+ /*
+ * Camera must be idle or we can't mess with the
+ * video setup.
+ */
+ mutex_lock(&cam->lock);
+ if (cam->opstate != S_IDLE) {
+ ret = -EBUSY;
+ goto out;
+ }
+ /*
+ * Let the sensor code look over and tweak the
+ * requested formatting.
+ */
+ ret = viacam_do_try_fmt(cam, &fmt->fmt.pix, &sfmt.fmt.pix);
+ if (ret)
+ goto out;
+ /*
+ * OK, let's commit to the new format.
+ */
+ cam->user_format = fmt->fmt.pix;
+ cam->sensor_format = sfmt.fmt.pix;
+ cam->mbus_code = f->mbus_code;
+ ret = viacam_configure_sensor(cam);
+ if (!ret)
+ ret = viacam_config_controller(cam);
+out:
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+static int viacam_querycap(struct file *filp, void *priv,
+ struct v4l2_capability *cap)
+{
+ strcpy(cap->driver, "via-camera");
+ strcpy(cap->card, "via-camera");
+ cap->version = 1;
+ cap->capabilities = V4L2_CAP_VIDEO_CAPTURE |
+ V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
+ return 0;
+}
+
+/*
+ * Streaming operations - pure videobuf stuff.
+ */
+static int viacam_reqbufs(struct file *filp, void *priv,
+ struct v4l2_requestbuffers *rb)
+{
+ struct via_camera *cam = priv;
+
+ return videobuf_reqbufs(&cam->vb_queue, rb);
+}
+
+static int viacam_querybuf(struct file *filp, void *priv,
+ struct v4l2_buffer *buf)
+{
+ struct via_camera *cam = priv;
+
+ return videobuf_querybuf(&cam->vb_queue, buf);
+}
+
+static int viacam_qbuf(struct file *filp, void *priv, struct v4l2_buffer *buf)
+{
+ struct via_camera *cam = priv;
+
+ return videobuf_qbuf(&cam->vb_queue, buf);
+}
+
+static int viacam_dqbuf(struct file *filp, void *priv, struct v4l2_buffer *buf)
+{
+ struct via_camera *cam = priv;
+
+ return videobuf_dqbuf(&cam->vb_queue, buf, filp->f_flags & O_NONBLOCK);
+}
+
+static int viacam_streamon(struct file *filp, void *priv, enum v4l2_buf_type t)
+{
+ struct via_camera *cam = priv;
+ int ret = 0;
+
+ if (t != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+ return -EINVAL;
+
+ mutex_lock(&cam->lock);
+ if (cam->opstate != S_IDLE) {
+ ret = -EBUSY;
+ goto out;
+ }
+ /*
+ * Enforce the V4l2 "only one owner gets to read data" rule.
+ */
+ if (cam->owner && cam->owner != filp) {
+ ret = -EBUSY;
+ goto out;
+ }
+ cam->owner = filp;
+ /*
+ * Configure things if need be.
+ */
+ if (test_bit(CF_CONFIG_NEEDED, &cam->flags)) {
+ ret = viacam_configure_sensor(cam);
+ if (ret)
+ goto out;
+ ret = viacam_config_controller(cam);
+ if (ret)
+ goto out;
+ }
+ /*
+ * If the CPU goes into C3, the DMA transfer gets corrupted and
+ * users start filing unsightly bug reports. Put in a "latency"
+ * requirement which will keep the CPU out of the deeper sleep
+ * states.
+ */
+ pm_qos_add_request(&cam->qos_request, PM_QOS_CPU_DMA_LATENCY, 50);
+ /*
+ * Fire things up.
+ */
+ INIT_LIST_HEAD(&cam->buffer_queue);
+ ret = videobuf_streamon(&cam->vb_queue);
+ if (!ret)
+ viacam_start_engine(cam);
+out:
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+static int viacam_streamoff(struct file *filp, void *priv, enum v4l2_buf_type t)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ if (t != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+ return -EINVAL;
+ mutex_lock(&cam->lock);
+ if (cam->opstate != S_RUNNING) {
+ ret = -EINVAL;
+ goto out;
+ }
+ pm_qos_remove_request(&cam->qos_request);
+ viacam_stop_engine(cam);
+ /*
+ * Videobuf will recycle all of the outstanding buffers, but
+ * we should be sure we don't retain any references to
+ * any of them.
+ */
+ ret = videobuf_streamoff(&cam->vb_queue);
+ INIT_LIST_HEAD(&cam->buffer_queue);
+out:
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+#ifdef CONFIG_VIDEO_V4L1_COMPAT
+static int viacam_vidiocgmbuf(struct file *filp, void *priv,
+ struct video_mbuf *mbuf)
+{
+ struct via_camera *cam = priv;
+
+ return videobuf_cgmbuf(&cam->vb_queue, mbuf, 6);
+}
+#endif
+
+/* G/S_PARM */
+
+static int viacam_g_parm(struct file *filp, void *priv,
+ struct v4l2_streamparm *parm)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = sensor_call(cam, video, g_parm, parm);
+ mutex_unlock(&cam->lock);
+ parm->parm.capture.readbuffers = cam->n_cap_bufs;
+ return ret;
+}
+
+static int viacam_s_parm(struct file *filp, void *priv,
+ struct v4l2_streamparm *parm)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = sensor_call(cam, video, s_parm, parm);
+ mutex_unlock(&cam->lock);
+ parm->parm.capture.readbuffers = cam->n_cap_bufs;
+ return ret;
+}
+
+static int viacam_enum_framesizes(struct file *filp, void *priv,
+ struct v4l2_frmsizeenum *sizes)
+{
+ if (sizes->index != 0)
+ return -EINVAL;
+ sizes->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
+ sizes->stepwise.min_width = QCIF_WIDTH;
+ sizes->stepwise.min_height = QCIF_HEIGHT;
+ sizes->stepwise.max_width = VGA_WIDTH;
+ sizes->stepwise.max_height = VGA_HEIGHT;
+ sizes->stepwise.step_width = sizes->stepwise.step_height = 1;
+ return 0;
+}
+
+static int viacam_enum_frameintervals(struct file *filp, void *priv,
+ struct v4l2_frmivalenum *interval)
+{
+ struct via_camera *cam = priv;
+ int ret;
+
+ mutex_lock(&cam->lock);
+ ret = sensor_call(cam, video, enum_frameintervals, interval);
+ mutex_unlock(&cam->lock);
+ return ret;
+}
+
+
+
+static const struct v4l2_ioctl_ops viacam_ioctl_ops = {
+ .vidioc_g_chip_ident = viacam_g_chip_ident,
+ .vidioc_queryctrl = viacam_queryctrl,
+ .vidioc_g_ctrl = viacam_g_ctrl,
+ .vidioc_s_ctrl = viacam_s_ctrl,
+ .vidioc_enum_input = viacam_enum_input,
+ .vidioc_g_input = viacam_g_input,
+ .vidioc_s_input = viacam_s_input,
+ .vidioc_s_std = viacam_s_std,
+ .vidioc_enum_fmt_vid_cap = viacam_enum_fmt_vid_cap,
+ .vidioc_try_fmt_vid_cap = viacam_try_fmt_vid_cap,
+ .vidioc_g_fmt_vid_cap = viacam_g_fmt_vid_cap,
+ .vidioc_s_fmt_vid_cap = viacam_s_fmt_vid_cap,
+ .vidioc_querycap = viacam_querycap,
+ .vidioc_reqbufs = viacam_reqbufs,
+ .vidioc_querybuf = viacam_querybuf,
+ .vidioc_qbuf = viacam_qbuf,
+ .vidioc_dqbuf = viacam_dqbuf,
+ .vidioc_streamon = viacam_streamon,
+ .vidioc_streamoff = viacam_streamoff,
+ .vidioc_g_parm = viacam_g_parm,
+ .vidioc_s_parm = viacam_s_parm,
+ .vidioc_enum_framesizes = viacam_enum_framesizes,
+ .vidioc_enum_frameintervals = viacam_enum_frameintervals,
+#ifdef CONFIG_VIDEO_V4L1_COMPAT
+ .vidiocgmbuf = viacam_vidiocgmbuf,
+#endif
+};
+
+/*----------------------------------------------------------------------------*/
+
+/*
+ * Power management.
+ */
+
+/*
+ * Setup stuff.
+ */
+
+static struct video_device viacam_v4l_template = {
+ .name = "via-camera",
+ .minor = -1,
+ .tvnorms = V4L2_STD_NTSC_M,
+ .current_norm = V4L2_STD_NTSC_M,
+ .fops = &viacam_fops,
+ .ioctl_ops = &viacam_ioctl_ops,
+ .release = video_device_release_empty, /* Check this */
+};
+
+
+static __devinit int viacam_probe(struct platform_device *pdev)
+{
+ int ret;
+ struct i2c_adapter *sensor_adapter;
+ struct viafb_dev *viadev = pdev->dev.platform_data;
+
+ /*
+ * Note that there are actually two capture channels on
+ * the device. We only deal with one for now. That
+ * is encoded here; nothing else assumes it's dealing with
+ * a unique capture device.
+ */
+ struct via_camera *cam;
+
+ /*
+ * Ensure that frame buffer memory has been set aside for
+ * this purpose. As an arbitrary limit, refuse to work
+ * with less than two frames of VGA 16-bit data.
+ *
+ * If we ever support the second port, we'll need to set
+ * aside more memory.
+ */
+ if (viadev->camera_fbmem_size < (VGA_HEIGHT*VGA_WIDTH*4)) {
+ printk(KERN_ERR "viacam: insufficient FB memory reserved\n");
+ return -ENOMEM;
+ }
+ if (viadev->engine_mmio == NULL) {
+ printk(KERN_ERR "viacam: No I/O memory, so no pictures\n");
+ return -ENOMEM;
+ }
+ /*
+ * Basic structure initialization.
+ */
+ cam = kzalloc (sizeof(struct via_camera), GFP_KERNEL);
+ if (cam == NULL)
+ return -ENOMEM;
+ via_cam_info = cam;
+ cam->platdev = pdev;
+ cam->viadev = viadev;
+ cam->users = 0;
+ cam->owner = NULL;
+ cam->opstate = S_IDLE;
+ cam->user_format = cam->sensor_format = viacam_def_pix_format;
+ mutex_init(&cam->lock);
+ INIT_LIST_HEAD(&cam->buffer_queue);
+ cam->mmio = viadev->engine_mmio;
+ cam->fbmem = viadev->fbmem;
+ cam->fb_offset = viadev->camera_fbmem_offset;
+ cam->flags = 1 << CF_CONFIG_NEEDED;
+ cam->mbus_code = via_def_mbus_code;
+ /*
+ * Tell V4L that we exist.
+ */
+ ret = v4l2_device_register(&pdev->dev, &cam->v4l2_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Unable to register v4l2 device\n");
+ return ret;
+ }
+ /*
+ * Convince the system that we can do DMA.
+ */
+ pdev->dev.dma_mask = &viadev->pdev->dma_mask;
+ dma_set_mask(&pdev->dev, 0xffffffff);
+ /*
+ * Fire up the capture port. The write to 0x78 looks purely
+ * OLPCish; any system will need to tweak 0x1e.
+ */
+ via_write_reg_mask(VIASR, 0x78, 0, 0x80);
+ via_write_reg_mask(VIASR, 0x1e, 0xc0, 0xc0);
+ /*
+ * Get the sensor powered up.
+ */
+ ret = via_sensor_power_setup(cam);
+ if (ret)
+ goto out_unregister;
+ via_sensor_power_up(cam);
+
+ /*
+ * See if we can't find it on the bus. The VIA_PORT_31 assumption
+ * is OLPC-specific. 0x42 assumption is ov7670-specific.
+ */
+ sensor_adapter = viafb_find_i2c_adapter(VIA_PORT_31);
+ cam->sensor = v4l2_i2c_new_subdev(&cam->v4l2_dev, sensor_adapter,
+ "ov7670", "ov7670", 0x42 >> 1, NULL);
+ if (cam->sensor == NULL) {
+ dev_err(&pdev->dev, "Unable to find the sensor!\n");
+ ret = -ENODEV;
+ goto out_power_down;
+ }
+ /*
+ * Get the IRQ.
+ */
+ viacam_int_disable(cam);
+ ret = request_threaded_irq(viadev->pdev->irq, viacam_quick_irq,
+ viacam_irq, IRQF_SHARED, "via-camera", cam);
+ if (ret)
+ goto out_power_down;
+ /*
+ * Tell V4l2 that we exist.
+ */
+ cam->vdev = viacam_v4l_template;
+ cam->vdev.v4l2_dev = &cam->v4l2_dev;
+ ret = video_register_device(&cam->vdev, VFL_TYPE_GRABBER, -1);
+ if (ret)
+ goto out_irq;
+ video_set_drvdata(&cam->vdev, cam);
+
+ /* Power the sensor down until somebody opens the device */
+ via_sensor_power_down(cam);
+ return 0;
+
+out_irq:
+ free_irq(viadev->pdev->irq, cam);
+out_power_down:
+ via_sensor_power_release(cam);
+out_unregister:
+ v4l2_device_unregister(&cam->v4l2_dev);
+ return ret;
+}
+
+static __devexit int viacam_remove(struct platform_device *pdev)
+{
+ struct via_camera *cam = via_cam_info;
+ struct viafb_dev *viadev = pdev->dev.platform_data;
+
+ video_unregister_device(&cam->vdev);
+ v4l2_device_unregister(&cam->v4l2_dev);
+ free_irq(viadev->pdev->irq, cam);
+ via_sensor_power_release(cam);
+ via_cam_info = NULL;
+ return 0;
+}
+
+
+static struct platform_driver viacam_driver = {
+ .driver = {
+ .name = "viafb-camera",
+ },
+ .probe = viacam_probe,
+ .remove = viacam_remove,
+};
+
+
+#ifdef CONFIG_OLPC_XO_1_5
+/*
+ * The OLPC folks put the serial port on the same pin as
+ * the camera. They also get grumpy if we break the
+ * serial port and keep them from using it. So we have
+ * to check the serial enable bit and not step on it.
+ */
+#define VIACAM_SERIAL_DEVFN 0x88
+#define VIACAM_SERIAL_CREG 0x46
+#define VIACAM_SERIAL_BIT 0x40
+
+static __devinit int viacam_check_serial_port(void)
+{
+ struct pci_bus *pbus = pci_find_bus(0, 0);
+ u8 cbyte;
+
+ pci_bus_read_config_byte(pbus, VIACAM_SERIAL_DEVFN,
+ VIACAM_SERIAL_CREG, &cbyte);
+ if ((cbyte & VIACAM_SERIAL_BIT) == 0)
+ return 0; /* Not enabled */
+ if (override_serial == 0) {
+ printk(KERN_NOTICE "Via camera: serial port is enabled, " \
+ "refusing to load.\n");
+ printk(KERN_NOTICE "Specify override_serial=1 to force " \
+ "module loading.\n");
+ return -EBUSY;
+ }
+ printk(KERN_NOTICE "Via camera: overriding serial port\n");
+ pci_bus_write_config_byte(pbus, VIACAM_SERIAL_DEVFN,
+ VIACAM_SERIAL_CREG, cbyte & ~VIACAM_SERIAL_BIT);
+ return 0;
+}
+#endif
+
+
+
+
+static int viacam_init(void)
+{
+#ifdef CONFIG_OLPC_XO_1_5
+ if (viacam_check_serial_port())
+ return -EBUSY;
+#endif
+ return platform_driver_register(&viacam_driver);
+}
+module_init(viacam_init);
+
+static void viacam_exit(void)
+{
+ platform_driver_unregister(&viacam_driver);
+}
+module_exit(viacam_exit);
projects / karo-tx-linux.git / commitdiff