2 * Driver for the VIA Chrome integrated camera controller.
4 * Copyright 2009,2010 Jonathan Corbet <corbet@lwn.net>
5 * Distributable under the terms of the GNU General Public License, version 2
7 * This work was supported by the One Laptop Per Child project
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/device.h>
12 #include <linux/list.h>
13 #include <linux/pci.h>
14 #include <linux/gpio.h>
15 #include <linux/interrupt.h>
16 #include <linux/platform_device.h>
17 #include <linux/videodev2.h>
18 #include <media/v4l2-device.h>
19 #include <media/v4l2-ioctl.h>
20 #include <media/v4l2-ctrls.h>
21 #include <media/v4l2-image-sizes.h>
22 #include <media/ov7670.h>
23 #include <media/videobuf-dma-sg.h>
24 #include <linux/delay.h>
25 #include <linux/dma-mapping.h>
26 #include <linux/pm_qos.h>
27 #include <linux/via-core.h>
28 #include <linux/via-gpio.h>
29 #include <linux/via_i2c.h>
32 #include "via-camera.h"
34 MODULE_ALIAS("platform:viafb-camera");
35 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
36 MODULE_DESCRIPTION("VIA framebuffer-based camera controller driver");
37 MODULE_LICENSE("GPL");
39 static bool flip_image;
40 module_param(flip_image, bool, 0444);
41 MODULE_PARM_DESC(flip_image,
42 "If set, the sensor will be instructed to flip the image "
45 static bool override_serial;
46 module_param(override_serial, bool, 0444);
47 MODULE_PARM_DESC(override_serial,
48 "The camera driver will normally refuse to load if "
49 "the XO 1.5 serial port is enabled. Set this option "
50 "to force-enable the camera.");
53 * The structure describing our camera.
55 enum viacam_opstate { S_IDLE = 0, S_RUNNING = 1 };
58 struct v4l2_device v4l2_dev;
59 struct v4l2_ctrl_handler ctrl_handler;
60 struct video_device vdev;
61 struct v4l2_subdev *sensor;
62 struct platform_device *platdev;
63 struct viafb_dev *viadev;
65 enum viacam_opstate opstate;
67 struct pm_qos_request qos_request;
69 * GPIO info for power/reset management
76 void __iomem *mmio; /* Where the registers live */
77 void __iomem *fbmem; /* Frame buffer memory */
78 u32 fb_offset; /* Reserved memory offset (FB) */
80 * Capture buffers and related. The controller supports
81 * up to three, so that's what we have here. These buffers
82 * live in frame buffer memory, so we don't call them "DMA".
84 unsigned int cb_offsets[3]; /* offsets into fb mem */
85 u8 __iomem *cb_addrs[3]; /* Kernel-space addresses */
86 int n_cap_bufs; /* How many are we using? */
88 struct videobuf_queue vb_queue;
89 struct list_head buffer_queue; /* prot. by reg_lock */
96 * Video format information. sensor_format is kept in a form
97 * that we can use to pass to the sensor. We always run the
98 * sensor in VGA resolution, though, and let the controller
99 * downscale things if need be. So we keep the "real*
100 * dimensions separately.
102 struct v4l2_pix_format sensor_format;
103 struct v4l2_pix_format user_format;
108 * Yes, this is a hack, but there's only going to be one of these
109 * on any system we know of.
111 static struct via_camera *via_cam_info;
114 * Flag values, manipulated with bitops
116 #define CF_DMA_ACTIVE 0 /* A frame is incoming */
117 #define CF_CONFIG_NEEDED 1 /* Must configure hardware */
121 * Nasty ugly v4l2 boilerplate.
123 #define sensor_call(cam, optype, func, args...) \
124 v4l2_subdev_call(cam->sensor, optype, func, ##args)
127 * Debugging and related.
129 #define cam_err(cam, fmt, arg...) \
130 dev_err(&(cam)->platdev->dev, fmt, ##arg);
131 #define cam_warn(cam, fmt, arg...) \
132 dev_warn(&(cam)->platdev->dev, fmt, ##arg);
133 #define cam_dbg(cam, fmt, arg...) \
134 dev_dbg(&(cam)->platdev->dev, fmt, ##arg);
137 * Format handling. This is ripped almost directly from Hans's changes
138 * to cafe_ccic.c. It's a little unfortunate; until this change, we
139 * didn't need to know anything about the format except its byte depth;
140 * now this information must be managed at this level too.
142 static struct via_format {
145 int bpp; /* Bytes per pixel */
149 .desc = "YUYV 4:2:2",
150 .pixelformat = V4L2_PIX_FMT_YUYV,
151 .mbus_code = MEDIA_BUS_FMT_YUYV8_2X8,
154 /* RGB444 and Bayer should be doable, but have never been
155 tested with this driver. RGB565 seems to work at the default
156 resolution, but results in color corruption when being scaled by
157 viacam_set_scaled(), and is disabled as a result. */
159 #define N_VIA_FMTS ARRAY_SIZE(via_formats)
161 static struct via_format *via_find_format(u32 pixelformat)
165 for (i = 0; i < N_VIA_FMTS; i++)
166 if (via_formats[i].pixelformat == pixelformat)
167 return via_formats + i;
168 /* Not found? Then return the first format. */
173 /*--------------------------------------------------------------------------*/
175 * Sensor power/reset management. This piece is OLPC-specific for
176 * sure; other configurations will have things connected differently.
178 static int via_sensor_power_setup(struct via_camera *cam)
182 cam->power_gpio = viafb_gpio_lookup("VGPIO3");
183 cam->reset_gpio = viafb_gpio_lookup("VGPIO2");
184 if (cam->power_gpio < 0 || cam->reset_gpio < 0) {
185 dev_err(&cam->platdev->dev, "Unable to find GPIO lines\n");
188 ret = gpio_request(cam->power_gpio, "viafb-camera");
190 dev_err(&cam->platdev->dev, "Unable to request power GPIO\n");
193 ret = gpio_request(cam->reset_gpio, "viafb-camera");
195 dev_err(&cam->platdev->dev, "Unable to request reset GPIO\n");
196 gpio_free(cam->power_gpio);
199 gpio_direction_output(cam->power_gpio, 0);
200 gpio_direction_output(cam->reset_gpio, 0);
205 * Power up the sensor and perform the reset dance.
207 static void via_sensor_power_up(struct via_camera *cam)
209 gpio_set_value(cam->power_gpio, 1);
210 gpio_set_value(cam->reset_gpio, 0);
211 msleep(20); /* Probably excessive */
212 gpio_set_value(cam->reset_gpio, 1);
216 static void via_sensor_power_down(struct via_camera *cam)
218 gpio_set_value(cam->power_gpio, 0);
219 gpio_set_value(cam->reset_gpio, 0);
223 static void via_sensor_power_release(struct via_camera *cam)
225 via_sensor_power_down(cam);
226 gpio_free(cam->power_gpio);
227 gpio_free(cam->reset_gpio);
230 /* --------------------------------------------------------------------------*/
234 * Manage the ov7670 "flip" bit, which needs special help.
236 static int viacam_set_flip(struct via_camera *cam)
238 struct v4l2_control ctrl;
240 memset(&ctrl, 0, sizeof(ctrl));
241 ctrl.id = V4L2_CID_VFLIP;
242 ctrl.value = flip_image;
243 return sensor_call(cam, core, s_ctrl, &ctrl);
247 * Configure the sensor. It's up to the caller to ensure
248 * that the camera is in the correct operating state.
250 static int viacam_configure_sensor(struct via_camera *cam)
252 struct v4l2_mbus_framefmt mbus_fmt;
255 v4l2_fill_mbus_format(&mbus_fmt, &cam->sensor_format, cam->mbus_code);
256 ret = sensor_call(cam, core, init, 0);
258 ret = sensor_call(cam, video, s_mbus_fmt, &mbus_fmt);
260 * OV7670 does weird things if flip is set *before* format...
263 ret = viacam_set_flip(cam);
269 /* --------------------------------------------------------------------------*/
271 * Some simple register accessors; they assume that the lock is held.
273 * Should we want to support the second capture engine, we could
274 * hide the register difference by adding 0x1000 to registers in the
277 static inline void viacam_write_reg(struct via_camera *cam,
280 iowrite32(value, cam->mmio + reg);
283 static inline int viacam_read_reg(struct via_camera *cam, int reg)
285 return ioread32(cam->mmio + reg);
288 static inline void viacam_write_reg_mask(struct via_camera *cam,
289 int reg, int value, int mask)
291 int tmp = viacam_read_reg(cam, reg);
293 tmp = (tmp & ~mask) | (value & mask);
294 viacam_write_reg(cam, reg, tmp);
298 /* --------------------------------------------------------------------------*/
299 /* Interrupt management and handling */
301 static irqreturn_t viacam_quick_irq(int irq, void *data)
303 struct via_camera *cam = data;
304 irqreturn_t ret = IRQ_NONE;
308 * All we do here is to clear the interrupts and tell
309 * the handler thread to wake up.
311 spin_lock(&cam->viadev->reg_lock);
312 icv = viacam_read_reg(cam, VCR_INTCTRL);
313 if (icv & VCR_IC_EAV) {
314 icv |= VCR_IC_EAV|VCR_IC_EVBI|VCR_IC_FFULL;
315 viacam_write_reg(cam, VCR_INTCTRL, icv);
316 ret = IRQ_WAKE_THREAD;
318 spin_unlock(&cam->viadev->reg_lock);
323 * Find the next videobuf buffer which has somebody waiting on it.
325 static struct videobuf_buffer *viacam_next_buffer(struct via_camera *cam)
328 struct videobuf_buffer *buf = NULL;
330 spin_lock_irqsave(&cam->viadev->reg_lock, flags);
331 if (cam->opstate != S_RUNNING)
333 if (list_empty(&cam->buffer_queue))
335 buf = list_entry(cam->buffer_queue.next, struct videobuf_buffer, queue);
336 if (!waitqueue_active(&buf->done)) {/* Nobody waiting */
340 list_del(&buf->queue);
341 buf->state = VIDEOBUF_ACTIVE;
343 spin_unlock_irqrestore(&cam->viadev->reg_lock, flags);
348 * The threaded IRQ handler.
350 static irqreturn_t viacam_irq(int irq, void *data)
353 struct videobuf_buffer *vb;
354 struct via_camera *cam = data;
355 struct videobuf_dmabuf *vdma;
358 * If there is no place to put the data frame, don't bother
359 * with anything else.
361 vb = viacam_next_buffer(cam);
365 * Figure out which buffer we just completed.
367 bufn = (viacam_read_reg(cam, VCR_INTCTRL) & VCR_IC_ACTBUF) >> 3;
370 bufn = cam->n_cap_bufs - 1;
372 * Copy over the data and let any waiters know.
374 vdma = videobuf_to_dma(vb);
375 viafb_dma_copy_out_sg(cam->cb_offsets[bufn], vdma->sglist, vdma->sglen);
376 vb->state = VIDEOBUF_DONE;
377 vb->size = cam->user_format.sizeimage;
385 * These functions must mess around with the general interrupt
386 * control register, which is relevant to much more than just the
387 * camera. Nothing else uses interrupts, though, as of this writing.
388 * Should that situation change, we'll have to improve support at
389 * the via-core level.
391 static void viacam_int_enable(struct via_camera *cam)
393 viacam_write_reg(cam, VCR_INTCTRL,
394 VCR_IC_INTEN|VCR_IC_EAV|VCR_IC_EVBI|VCR_IC_FFULL);
395 viafb_irq_enable(VDE_I_C0AVEN);
398 static void viacam_int_disable(struct via_camera *cam)
400 viafb_irq_disable(VDE_I_C0AVEN);
401 viacam_write_reg(cam, VCR_INTCTRL, 0);
406 /* --------------------------------------------------------------------------*/
407 /* Controller operations */
410 * Set up our capture buffers in framebuffer memory.
412 static int viacam_ctlr_cbufs(struct via_camera *cam)
414 int nbuf = cam->viadev->camera_fbmem_size/cam->sensor_format.sizeimage;
419 * See how many buffers we can work with.
423 viacam_write_reg_mask(cam, VCR_CAPINTC, VCR_CI_3BUFS,
425 } else if (nbuf == 2) {
427 viacam_write_reg_mask(cam, VCR_CAPINTC, 0, VCR_CI_3BUFS);
429 cam_warn(cam, "Insufficient frame buffer memory\n");
435 offset = cam->fb_offset;
436 for (i = 0; i < cam->n_cap_bufs; i++) {
437 cam->cb_offsets[i] = offset;
438 cam->cb_addrs[i] = cam->fbmem + offset;
439 viacam_write_reg(cam, VCR_VBUF1 + i*4, offset & VCR_VBUF_MASK);
440 offset += cam->sensor_format.sizeimage;
446 * Set the scaling register for downscaling the image.
448 * This register works like this... Vertical scaling is enabled
449 * by bit 26; if that bit is set, downscaling is controlled by the
450 * value in bits 16:25. Those bits are divided by 1024 to get
451 * the scaling factor; setting just bit 25 thus cuts the height
454 * Horizontal scaling works about the same, but it's enabled by
455 * bit 11, with bits 0:10 giving the numerator of a fraction
456 * (over 2048) for the scaling value.
458 * This function is naive in that, if the user departs from
459 * the 3x4 VGA scaling factor, the image will distort. We
460 * could work around that if it really seemed important.
462 static void viacam_set_scale(struct via_camera *cam)
464 unsigned int avscale;
467 if (cam->user_format.width == VGA_WIDTH)
470 sf = (cam->user_format.width*2048)/VGA_WIDTH;
471 avscale = VCR_AVS_HEN | sf;
473 if (cam->user_format.height < VGA_HEIGHT) {
474 sf = (1024*cam->user_format.height)/VGA_HEIGHT;
475 avscale |= VCR_AVS_VEN | (sf << 16);
477 viacam_write_reg(cam, VCR_AVSCALE, avscale);
482 * Configure image-related information into the capture engine.
484 static void viacam_ctlr_image(struct via_camera *cam)
489 * Disable clock before messing with stuff - from the via
492 viacam_write_reg(cam, VCR_CAPINTC, ~(VCR_CI_ENABLE|VCR_CI_CLKEN));
494 * Set up the controller for VGA resolution, modulo magic
495 * offsets from the via sample driver.
497 viacam_write_reg(cam, VCR_HORRANGE, 0x06200120);
498 viacam_write_reg(cam, VCR_VERTRANGE, 0x01de0000);
499 viacam_set_scale(cam);
503 viacam_write_reg(cam, VCR_MAXDATA,
504 (cam->sensor_format.height << 16) |
505 (cam->sensor_format.bytesperline >> 3));
506 viacam_write_reg(cam, VCR_MAXVBI, 0);
507 viacam_write_reg(cam, VCR_VSTRIDE,
508 cam->user_format.bytesperline & VCR_VS_STRIDE);
510 * Set up the capture interface control register,
511 * everything but the "go" bit.
513 * The FIFO threshold is a bit of a magic number; 8 is what
514 * VIA's sample code uses.
516 cicreg = VCR_CI_CLKEN |
517 0x08000000 | /* FIFO threshold */
518 VCR_CI_FLDINV | /* OLPC-specific? */
519 VCR_CI_VREFINV | /* OLPC-specific? */
520 VCR_CI_DIBOTH | /* Capture both fields */
522 if (cam->n_cap_bufs == 3)
523 cicreg |= VCR_CI_3BUFS;
525 * YUV formats need different byte swapping than RGB.
527 if (cam->user_format.pixelformat == V4L2_PIX_FMT_YUYV)
528 cicreg |= VCR_CI_YUYV;
530 cicreg |= VCR_CI_UYVY;
531 viacam_write_reg(cam, VCR_CAPINTC, cicreg);
535 static int viacam_config_controller(struct via_camera *cam)
540 spin_lock_irqsave(&cam->viadev->reg_lock, flags);
541 ret = viacam_ctlr_cbufs(cam);
543 viacam_ctlr_image(cam);
544 spin_unlock_irqrestore(&cam->viadev->reg_lock, flags);
545 clear_bit(CF_CONFIG_NEEDED, &cam->flags);
550 * Make it start grabbing data.
552 static void viacam_start_engine(struct via_camera *cam)
554 spin_lock_irq(&cam->viadev->reg_lock);
556 viacam_write_reg_mask(cam, VCR_CAPINTC, VCR_CI_ENABLE, VCR_CI_ENABLE);
557 viacam_int_enable(cam);
558 (void) viacam_read_reg(cam, VCR_CAPINTC); /* Force post */
559 cam->opstate = S_RUNNING;
560 spin_unlock_irq(&cam->viadev->reg_lock);
564 static void viacam_stop_engine(struct via_camera *cam)
566 spin_lock_irq(&cam->viadev->reg_lock);
567 viacam_int_disable(cam);
568 viacam_write_reg_mask(cam, VCR_CAPINTC, 0, VCR_CI_ENABLE);
569 (void) viacam_read_reg(cam, VCR_CAPINTC); /* Force post */
570 cam->opstate = S_IDLE;
571 spin_unlock_irq(&cam->viadev->reg_lock);
575 /* --------------------------------------------------------------------------*/
576 /* Videobuf callback ops */
579 * buffer_setup. The purpose of this one would appear to be to tell
580 * videobuf how big a single image is. It's also evidently up to us
581 * to put some sort of limit on the maximum number of buffers allowed.
583 static int viacam_vb_buf_setup(struct videobuf_queue *q,
584 unsigned int *count, unsigned int *size)
586 struct via_camera *cam = q->priv_data;
588 *size = cam->user_format.sizeimage;
589 if (*count == 0 || *count > 6) /* Arbitrary number */
597 static int viacam_vb_buf_prepare(struct videobuf_queue *q,
598 struct videobuf_buffer *vb, enum v4l2_field field)
600 struct via_camera *cam = q->priv_data;
602 vb->size = cam->user_format.sizeimage;
603 vb->width = cam->user_format.width; /* bytesperline???? */
604 vb->height = cam->user_format.height;
606 if (vb->state == VIDEOBUF_NEEDS_INIT) {
607 int ret = videobuf_iolock(q, vb, NULL);
611 vb->state = VIDEOBUF_PREPARED;
616 * We've got a buffer to put data into.
618 * FIXME: check for a running engine and valid buffers?
620 static void viacam_vb_buf_queue(struct videobuf_queue *q,
621 struct videobuf_buffer *vb)
623 struct via_camera *cam = q->priv_data;
626 * Note that videobuf holds the lock when it calls
627 * us, so we need not (indeed, cannot) take it here.
629 vb->state = VIDEOBUF_QUEUED;
630 list_add_tail(&vb->queue, &cam->buffer_queue);
636 static void viacam_vb_buf_release(struct videobuf_queue *q,
637 struct videobuf_buffer *vb)
639 struct via_camera *cam = q->priv_data;
641 videobuf_dma_unmap(&cam->platdev->dev, videobuf_to_dma(vb));
642 videobuf_dma_free(videobuf_to_dma(vb));
643 vb->state = VIDEOBUF_NEEDS_INIT;
646 static const struct videobuf_queue_ops viacam_vb_ops = {
647 .buf_setup = viacam_vb_buf_setup,
648 .buf_prepare = viacam_vb_buf_prepare,
649 .buf_queue = viacam_vb_buf_queue,
650 .buf_release = viacam_vb_buf_release,
653 /* --------------------------------------------------------------------------*/
654 /* File operations */
656 static int viacam_open(struct file *filp)
658 struct via_camera *cam = video_drvdata(filp);
660 filp->private_data = cam;
662 * Note the new user. If this is the first one, we'll also
663 * need to power up the sensor.
665 mutex_lock(&cam->lock);
666 if (cam->users == 0) {
667 int ret = viafb_request_dma();
670 mutex_unlock(&cam->lock);
673 via_sensor_power_up(cam);
674 set_bit(CF_CONFIG_NEEDED, &cam->flags);
676 * Hook into videobuf. Evidently this cannot fail.
678 videobuf_queue_sg_init(&cam->vb_queue, &viacam_vb_ops,
679 &cam->platdev->dev, &cam->viadev->reg_lock,
680 V4L2_BUF_TYPE_VIDEO_CAPTURE, V4L2_FIELD_NONE,
681 sizeof(struct videobuf_buffer), cam, NULL);
684 mutex_unlock(&cam->lock);
688 static int viacam_release(struct file *filp)
690 struct via_camera *cam = video_drvdata(filp);
692 mutex_lock(&cam->lock);
695 * If the "owner" is closing, shut down any ongoing
698 if (filp == cam->owner) {
699 videobuf_stop(&cam->vb_queue);
701 * We don't hold the spinlock here, but, if release()
702 * is being called by the owner, nobody else will
703 * be changing the state. And an extra stop would
706 if (cam->opstate != S_IDLE)
707 viacam_stop_engine(cam);
711 * Last one out needs to turn out the lights.
713 if (cam->users == 0) {
714 videobuf_mmap_free(&cam->vb_queue);
715 via_sensor_power_down(cam);
718 mutex_unlock(&cam->lock);
723 * Read a frame from the device.
725 static ssize_t viacam_read(struct file *filp, char __user *buffer,
726 size_t len, loff_t *pos)
728 struct via_camera *cam = video_drvdata(filp);
731 mutex_lock(&cam->lock);
733 * Enforce the V4l2 "only one owner gets to read data" rule.
735 if (cam->owner && cam->owner != filp) {
741 * Do we need to configure the hardware?
743 if (test_bit(CF_CONFIG_NEEDED, &cam->flags)) {
744 ret = viacam_configure_sensor(cam);
746 ret = viacam_config_controller(cam);
751 * Fire up the capture engine, then have videobuf do
752 * the heavy lifting. Someday it would be good to avoid
753 * stopping and restarting the engine each time.
755 INIT_LIST_HEAD(&cam->buffer_queue);
756 viacam_start_engine(cam);
757 ret = videobuf_read_stream(&cam->vb_queue, buffer, len, pos, 0,
758 filp->f_flags & O_NONBLOCK);
759 viacam_stop_engine(cam);
760 /* videobuf_stop() ?? */
763 mutex_unlock(&cam->lock);
768 static unsigned int viacam_poll(struct file *filp, struct poll_table_struct *pt)
770 struct via_camera *cam = video_drvdata(filp);
772 return videobuf_poll_stream(filp, &cam->vb_queue, pt);
776 static int viacam_mmap(struct file *filp, struct vm_area_struct *vma)
778 struct via_camera *cam = video_drvdata(filp);
780 return videobuf_mmap_mapper(&cam->vb_queue, vma);
785 static const struct v4l2_file_operations viacam_fops = {
786 .owner = THIS_MODULE,
788 .release = viacam_release,
792 .unlocked_ioctl = video_ioctl2,
795 /*----------------------------------------------------------------------------*/
797 * The long list of v4l2 ioctl ops
803 static int viacam_enum_input(struct file *filp, void *priv,
804 struct v4l2_input *input)
806 if (input->index != 0)
809 input->type = V4L2_INPUT_TYPE_CAMERA;
810 input->std = V4L2_STD_ALL; /* Not sure what should go here */
811 strcpy(input->name, "Camera");
815 static int viacam_g_input(struct file *filp, void *priv, unsigned int *i)
821 static int viacam_s_input(struct file *filp, void *priv, unsigned int i)
828 static int viacam_s_std(struct file *filp, void *priv, v4l2_std_id std)
833 static int viacam_g_std(struct file *filp, void *priv, v4l2_std_id *std)
835 *std = V4L2_STD_NTSC_M;
840 * Video format stuff. Here is our default format until
841 * user space messes with things.
843 static const struct v4l2_pix_format viacam_def_pix_format = {
845 .height = VGA_HEIGHT,
846 .pixelformat = V4L2_PIX_FMT_YUYV,
847 .field = V4L2_FIELD_NONE,
848 .bytesperline = VGA_WIDTH * 2,
849 .sizeimage = VGA_WIDTH * VGA_HEIGHT * 2,
852 static const u32 via_def_mbus_code = MEDIA_BUS_FMT_YUYV8_2X8;
854 static int viacam_enum_fmt_vid_cap(struct file *filp, void *priv,
855 struct v4l2_fmtdesc *fmt)
857 if (fmt->index >= N_VIA_FMTS)
859 strlcpy(fmt->description, via_formats[fmt->index].desc,
860 sizeof(fmt->description));
861 fmt->pixelformat = via_formats[fmt->index].pixelformat;
866 * Figure out proper image dimensions, but always force the
869 static void viacam_fmt_pre(struct v4l2_pix_format *userfmt,
870 struct v4l2_pix_format *sensorfmt)
872 *sensorfmt = *userfmt;
873 if (userfmt->width < QCIF_WIDTH || userfmt->height < QCIF_HEIGHT) {
874 userfmt->width = QCIF_WIDTH;
875 userfmt->height = QCIF_HEIGHT;
877 if (userfmt->width > VGA_WIDTH || userfmt->height > VGA_HEIGHT) {
878 userfmt->width = VGA_WIDTH;
879 userfmt->height = VGA_HEIGHT;
881 sensorfmt->width = VGA_WIDTH;
882 sensorfmt->height = VGA_HEIGHT;
885 static void viacam_fmt_post(struct v4l2_pix_format *userfmt,
886 struct v4l2_pix_format *sensorfmt)
888 struct via_format *f = via_find_format(userfmt->pixelformat);
890 sensorfmt->bytesperline = sensorfmt->width * f->bpp;
891 sensorfmt->sizeimage = sensorfmt->height * sensorfmt->bytesperline;
892 userfmt->pixelformat = sensorfmt->pixelformat;
893 userfmt->field = sensorfmt->field;
894 userfmt->bytesperline = 2 * userfmt->width;
895 userfmt->sizeimage = userfmt->bytesperline * userfmt->height;
900 * The real work of figuring out a workable format.
902 static int viacam_do_try_fmt(struct via_camera *cam,
903 struct v4l2_pix_format *upix, struct v4l2_pix_format *spix)
906 struct v4l2_mbus_framefmt mbus_fmt;
907 struct via_format *f = via_find_format(upix->pixelformat);
909 upix->pixelformat = f->pixelformat;
910 viacam_fmt_pre(upix, spix);
911 v4l2_fill_mbus_format(&mbus_fmt, spix, f->mbus_code);
912 ret = sensor_call(cam, video, try_mbus_fmt, &mbus_fmt);
913 v4l2_fill_pix_format(spix, &mbus_fmt);
914 viacam_fmt_post(upix, spix);
920 static int viacam_try_fmt_vid_cap(struct file *filp, void *priv,
921 struct v4l2_format *fmt)
923 struct via_camera *cam = priv;
924 struct v4l2_format sfmt;
927 mutex_lock(&cam->lock);
928 ret = viacam_do_try_fmt(cam, &fmt->fmt.pix, &sfmt.fmt.pix);
929 mutex_unlock(&cam->lock);
934 static int viacam_g_fmt_vid_cap(struct file *filp, void *priv,
935 struct v4l2_format *fmt)
937 struct via_camera *cam = priv;
939 mutex_lock(&cam->lock);
940 fmt->fmt.pix = cam->user_format;
941 mutex_unlock(&cam->lock);
945 static int viacam_s_fmt_vid_cap(struct file *filp, void *priv,
946 struct v4l2_format *fmt)
948 struct via_camera *cam = priv;
950 struct v4l2_format sfmt;
951 struct via_format *f = via_find_format(fmt->fmt.pix.pixelformat);
954 * Camera must be idle or we can't mess with the
957 mutex_lock(&cam->lock);
958 if (cam->opstate != S_IDLE) {
963 * Let the sensor code look over and tweak the
964 * requested formatting.
966 ret = viacam_do_try_fmt(cam, &fmt->fmt.pix, &sfmt.fmt.pix);
970 * OK, let's commit to the new format.
972 cam->user_format = fmt->fmt.pix;
973 cam->sensor_format = sfmt.fmt.pix;
974 cam->mbus_code = f->mbus_code;
975 ret = viacam_configure_sensor(cam);
977 ret = viacam_config_controller(cam);
979 mutex_unlock(&cam->lock);
983 static int viacam_querycap(struct file *filp, void *priv,
984 struct v4l2_capability *cap)
986 strcpy(cap->driver, "via-camera");
987 strcpy(cap->card, "via-camera");
988 cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
989 V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
990 cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
995 * Streaming operations - pure videobuf stuff.
997 static int viacam_reqbufs(struct file *filp, void *priv,
998 struct v4l2_requestbuffers *rb)
1000 struct via_camera *cam = priv;
1002 return videobuf_reqbufs(&cam->vb_queue, rb);
1005 static int viacam_querybuf(struct file *filp, void *priv,
1006 struct v4l2_buffer *buf)
1008 struct via_camera *cam = priv;
1010 return videobuf_querybuf(&cam->vb_queue, buf);
1013 static int viacam_qbuf(struct file *filp, void *priv, struct v4l2_buffer *buf)
1015 struct via_camera *cam = priv;
1017 return videobuf_qbuf(&cam->vb_queue, buf);
1020 static int viacam_dqbuf(struct file *filp, void *priv, struct v4l2_buffer *buf)
1022 struct via_camera *cam = priv;
1024 return videobuf_dqbuf(&cam->vb_queue, buf, filp->f_flags & O_NONBLOCK);
1027 static int viacam_streamon(struct file *filp, void *priv, enum v4l2_buf_type t)
1029 struct via_camera *cam = priv;
1032 if (t != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1035 mutex_lock(&cam->lock);
1036 if (cam->opstate != S_IDLE) {
1041 * Enforce the V4l2 "only one owner gets to read data" rule.
1043 if (cam->owner && cam->owner != filp) {
1049 * Configure things if need be.
1051 if (test_bit(CF_CONFIG_NEEDED, &cam->flags)) {
1052 ret = viacam_configure_sensor(cam);
1055 ret = viacam_config_controller(cam);
1060 * If the CPU goes into C3, the DMA transfer gets corrupted and
1061 * users start filing unsightly bug reports. Put in a "latency"
1062 * requirement which will keep the CPU out of the deeper sleep
1065 pm_qos_add_request(&cam->qos_request, PM_QOS_CPU_DMA_LATENCY, 50);
1069 INIT_LIST_HEAD(&cam->buffer_queue);
1070 ret = videobuf_streamon(&cam->vb_queue);
1072 viacam_start_engine(cam);
1074 mutex_unlock(&cam->lock);
1078 static int viacam_streamoff(struct file *filp, void *priv, enum v4l2_buf_type t)
1080 struct via_camera *cam = priv;
1083 if (t != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1085 mutex_lock(&cam->lock);
1086 if (cam->opstate != S_RUNNING) {
1090 pm_qos_remove_request(&cam->qos_request);
1091 viacam_stop_engine(cam);
1093 * Videobuf will recycle all of the outstanding buffers, but
1094 * we should be sure we don't retain any references to
1097 ret = videobuf_streamoff(&cam->vb_queue);
1098 INIT_LIST_HEAD(&cam->buffer_queue);
1100 mutex_unlock(&cam->lock);
1106 static int viacam_g_parm(struct file *filp, void *priv,
1107 struct v4l2_streamparm *parm)
1109 struct via_camera *cam = priv;
1112 mutex_lock(&cam->lock);
1113 ret = sensor_call(cam, video, g_parm, parm);
1114 mutex_unlock(&cam->lock);
1115 parm->parm.capture.readbuffers = cam->n_cap_bufs;
1119 static int viacam_s_parm(struct file *filp, void *priv,
1120 struct v4l2_streamparm *parm)
1122 struct via_camera *cam = priv;
1125 mutex_lock(&cam->lock);
1126 ret = sensor_call(cam, video, s_parm, parm);
1127 mutex_unlock(&cam->lock);
1128 parm->parm.capture.readbuffers = cam->n_cap_bufs;
1132 static int viacam_enum_framesizes(struct file *filp, void *priv,
1133 struct v4l2_frmsizeenum *sizes)
1135 if (sizes->index != 0)
1137 sizes->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
1138 sizes->stepwise.min_width = QCIF_WIDTH;
1139 sizes->stepwise.min_height = QCIF_HEIGHT;
1140 sizes->stepwise.max_width = VGA_WIDTH;
1141 sizes->stepwise.max_height = VGA_HEIGHT;
1142 sizes->stepwise.step_width = sizes->stepwise.step_height = 1;
1146 static int viacam_enum_frameintervals(struct file *filp, void *priv,
1147 struct v4l2_frmivalenum *interval)
1149 struct via_camera *cam = priv;
1150 struct v4l2_subdev_frame_interval_enum fie = {
1151 .index = interval->index,
1152 .code = cam->mbus_code,
1153 .width = cam->sensor_format.width,
1154 .height = cam->sensor_format.height,
1155 .which = V4L2_SUBDEV_FORMAT_ACTIVE,
1159 mutex_lock(&cam->lock);
1160 ret = sensor_call(cam, pad, enum_frame_interval, NULL, &fie);
1161 mutex_unlock(&cam->lock);
1164 interval->type = V4L2_FRMIVAL_TYPE_DISCRETE;
1165 interval->discrete = fie.interval;
1171 static const struct v4l2_ioctl_ops viacam_ioctl_ops = {
1172 .vidioc_enum_input = viacam_enum_input,
1173 .vidioc_g_input = viacam_g_input,
1174 .vidioc_s_input = viacam_s_input,
1175 .vidioc_s_std = viacam_s_std,
1176 .vidioc_g_std = viacam_g_std,
1177 .vidioc_enum_fmt_vid_cap = viacam_enum_fmt_vid_cap,
1178 .vidioc_try_fmt_vid_cap = viacam_try_fmt_vid_cap,
1179 .vidioc_g_fmt_vid_cap = viacam_g_fmt_vid_cap,
1180 .vidioc_s_fmt_vid_cap = viacam_s_fmt_vid_cap,
1181 .vidioc_querycap = viacam_querycap,
1182 .vidioc_reqbufs = viacam_reqbufs,
1183 .vidioc_querybuf = viacam_querybuf,
1184 .vidioc_qbuf = viacam_qbuf,
1185 .vidioc_dqbuf = viacam_dqbuf,
1186 .vidioc_streamon = viacam_streamon,
1187 .vidioc_streamoff = viacam_streamoff,
1188 .vidioc_g_parm = viacam_g_parm,
1189 .vidioc_s_parm = viacam_s_parm,
1190 .vidioc_enum_framesizes = viacam_enum_framesizes,
1191 .vidioc_enum_frameintervals = viacam_enum_frameintervals,
1194 /*----------------------------------------------------------------------------*/
1201 static int viacam_suspend(void *priv)
1203 struct via_camera *cam = priv;
1204 enum viacam_opstate state = cam->opstate;
1206 if (cam->opstate != S_IDLE) {
1207 viacam_stop_engine(cam);
1208 cam->opstate = state; /* So resume restarts */
1214 static int viacam_resume(void *priv)
1216 struct via_camera *cam = priv;
1220 * Get back to a reasonable operating state.
1222 via_write_reg_mask(VIASR, 0x78, 0, 0x80);
1223 via_write_reg_mask(VIASR, 0x1e, 0xc0, 0xc0);
1224 viacam_int_disable(cam);
1225 set_bit(CF_CONFIG_NEEDED, &cam->flags);
1227 * Make sure the sensor's power state is correct
1230 via_sensor_power_up(cam);
1232 via_sensor_power_down(cam);
1234 * If it was operating, try to restart it.
1236 if (cam->opstate != S_IDLE) {
1237 mutex_lock(&cam->lock);
1238 ret = viacam_configure_sensor(cam);
1240 ret = viacam_config_controller(cam);
1241 mutex_unlock(&cam->lock);
1243 viacam_start_engine(cam);
1249 static struct viafb_pm_hooks viacam_pm_hooks = {
1250 .suspend = viacam_suspend,
1251 .resume = viacam_resume
1254 #endif /* CONFIG_PM */
1260 static struct video_device viacam_v4l_template = {
1261 .name = "via-camera",
1263 .tvnorms = V4L2_STD_NTSC_M,
1264 .fops = &viacam_fops,
1265 .ioctl_ops = &viacam_ioctl_ops,
1266 .release = video_device_release_empty, /* Check this */
1270 * The OLPC folks put the serial port on the same pin as
1271 * the camera. They also get grumpy if we break the
1272 * serial port and keep them from using it. So we have
1273 * to check the serial enable bit and not step on it.
1275 #define VIACAM_SERIAL_DEVFN 0x88
1276 #define VIACAM_SERIAL_CREG 0x46
1277 #define VIACAM_SERIAL_BIT 0x40
1279 static bool viacam_serial_is_enabled(void)
1281 struct pci_bus *pbus = pci_find_bus(0, 0);
1286 pci_bus_read_config_byte(pbus, VIACAM_SERIAL_DEVFN,
1287 VIACAM_SERIAL_CREG, &cbyte);
1288 if ((cbyte & VIACAM_SERIAL_BIT) == 0)
1289 return false; /* Not enabled */
1290 if (!override_serial) {
1291 printk(KERN_NOTICE "Via camera: serial port is enabled, " \
1292 "refusing to load.\n");
1293 printk(KERN_NOTICE "Specify override_serial=1 to force " \
1294 "module loading.\n");
1297 printk(KERN_NOTICE "Via camera: overriding serial port\n");
1298 pci_bus_write_config_byte(pbus, VIACAM_SERIAL_DEVFN,
1299 VIACAM_SERIAL_CREG, cbyte & ~VIACAM_SERIAL_BIT);
1303 static struct ov7670_config sensor_cfg = {
1304 /* The XO-1.5 (only known user) clocks the camera at 90MHz. */
1308 static int viacam_probe(struct platform_device *pdev)
1311 struct i2c_adapter *sensor_adapter;
1312 struct viafb_dev *viadev = pdev->dev.platform_data;
1313 struct i2c_board_info ov7670_info = {
1316 .platform_data = &sensor_cfg,
1320 * Note that there are actually two capture channels on
1321 * the device. We only deal with one for now. That
1322 * is encoded here; nothing else assumes it's dealing with
1323 * a unique capture device.
1325 struct via_camera *cam;
1328 * Ensure that frame buffer memory has been set aside for
1329 * this purpose. As an arbitrary limit, refuse to work
1330 * with less than two frames of VGA 16-bit data.
1332 * If we ever support the second port, we'll need to set
1333 * aside more memory.
1335 if (viadev->camera_fbmem_size < (VGA_HEIGHT*VGA_WIDTH*4)) {
1336 printk(KERN_ERR "viacam: insufficient FB memory reserved\n");
1339 if (viadev->engine_mmio == NULL) {
1340 printk(KERN_ERR "viacam: No I/O memory, so no pictures\n");
1344 if (machine_is_olpc() && viacam_serial_is_enabled())
1348 * Basic structure initialization.
1350 cam = kzalloc (sizeof(struct via_camera), GFP_KERNEL);
1354 cam->platdev = pdev;
1355 cam->viadev = viadev;
1358 cam->opstate = S_IDLE;
1359 cam->user_format = cam->sensor_format = viacam_def_pix_format;
1360 mutex_init(&cam->lock);
1361 INIT_LIST_HEAD(&cam->buffer_queue);
1362 cam->mmio = viadev->engine_mmio;
1363 cam->fbmem = viadev->fbmem;
1364 cam->fb_offset = viadev->camera_fbmem_offset;
1365 cam->flags = 1 << CF_CONFIG_NEEDED;
1366 cam->mbus_code = via_def_mbus_code;
1368 * Tell V4L that we exist.
1370 ret = v4l2_device_register(&pdev->dev, &cam->v4l2_dev);
1372 dev_err(&pdev->dev, "Unable to register v4l2 device\n");
1375 ret = v4l2_ctrl_handler_init(&cam->ctrl_handler, 10);
1377 goto out_unregister;
1378 cam->v4l2_dev.ctrl_handler = &cam->ctrl_handler;
1380 * Convince the system that we can do DMA.
1382 pdev->dev.dma_mask = &viadev->pdev->dma_mask;
1383 dma_set_mask(&pdev->dev, 0xffffffff);
1385 * Fire up the capture port. The write to 0x78 looks purely
1386 * OLPCish; any system will need to tweak 0x1e.
1388 via_write_reg_mask(VIASR, 0x78, 0, 0x80);
1389 via_write_reg_mask(VIASR, 0x1e, 0xc0, 0xc0);
1391 * Get the sensor powered up.
1393 ret = via_sensor_power_setup(cam);
1395 goto out_ctrl_hdl_free;
1396 via_sensor_power_up(cam);
1399 * See if we can't find it on the bus. The VIA_PORT_31 assumption
1400 * is OLPC-specific. 0x42 assumption is ov7670-specific.
1402 sensor_adapter = viafb_find_i2c_adapter(VIA_PORT_31);
1403 cam->sensor = v4l2_i2c_new_subdev_board(&cam->v4l2_dev, sensor_adapter,
1404 &ov7670_info, NULL);
1405 if (cam->sensor == NULL) {
1406 dev_err(&pdev->dev, "Unable to find the sensor!\n");
1408 goto out_power_down;
1413 viacam_int_disable(cam);
1414 ret = request_threaded_irq(viadev->pdev->irq, viacam_quick_irq,
1415 viacam_irq, IRQF_SHARED, "via-camera", cam);
1417 goto out_power_down;
1419 * Tell V4l2 that we exist.
1421 cam->vdev = viacam_v4l_template;
1422 cam->vdev.v4l2_dev = &cam->v4l2_dev;
1423 ret = video_register_device(&cam->vdev, VFL_TYPE_GRABBER, -1);
1426 video_set_drvdata(&cam->vdev, cam);
1430 * Hook into PM events
1432 viacam_pm_hooks.private = cam;
1433 viafb_pm_register(&viacam_pm_hooks);
1436 /* Power the sensor down until somebody opens the device */
1437 via_sensor_power_down(cam);
1441 free_irq(viadev->pdev->irq, cam);
1443 via_sensor_power_release(cam);
1445 v4l2_ctrl_handler_free(&cam->ctrl_handler);
1447 v4l2_device_unregister(&cam->v4l2_dev);
1453 static int viacam_remove(struct platform_device *pdev)
1455 struct via_camera *cam = via_cam_info;
1456 struct viafb_dev *viadev = pdev->dev.platform_data;
1458 video_unregister_device(&cam->vdev);
1459 v4l2_device_unregister(&cam->v4l2_dev);
1460 free_irq(viadev->pdev->irq, cam);
1461 via_sensor_power_release(cam);
1462 v4l2_ctrl_handler_free(&cam->ctrl_handler);
1464 via_cam_info = NULL;
1468 static struct platform_driver viacam_driver = {
1470 .name = "viafb-camera",
1472 .probe = viacam_probe,
1473 .remove = viacam_remove,
1476 module_platform_driver(viacam_driver);