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_subdev_format format = {
253 .which = V4L2_SUBDEV_FORMAT_ACTIVE,
257 v4l2_fill_mbus_format(&format.format, &cam->sensor_format, cam->mbus_code);
258 ret = sensor_call(cam, core, init, 0);
260 ret = sensor_call(cam, pad, set_fmt, NULL, &format);
262 * OV7670 does weird things if flip is set *before* format...
265 ret = viacam_set_flip(cam);
271 /* --------------------------------------------------------------------------*/
273 * Some simple register accessors; they assume that the lock is held.
275 * Should we want to support the second capture engine, we could
276 * hide the register difference by adding 0x1000 to registers in the
279 static inline void viacam_write_reg(struct via_camera *cam,
282 iowrite32(value, cam->mmio + reg);
285 static inline int viacam_read_reg(struct via_camera *cam, int reg)
287 return ioread32(cam->mmio + reg);
290 static inline void viacam_write_reg_mask(struct via_camera *cam,
291 int reg, int value, int mask)
293 int tmp = viacam_read_reg(cam, reg);
295 tmp = (tmp & ~mask) | (value & mask);
296 viacam_write_reg(cam, reg, tmp);
300 /* --------------------------------------------------------------------------*/
301 /* Interrupt management and handling */
303 static irqreturn_t viacam_quick_irq(int irq, void *data)
305 struct via_camera *cam = data;
306 irqreturn_t ret = IRQ_NONE;
310 * All we do here is to clear the interrupts and tell
311 * the handler thread to wake up.
313 spin_lock(&cam->viadev->reg_lock);
314 icv = viacam_read_reg(cam, VCR_INTCTRL);
315 if (icv & VCR_IC_EAV) {
316 icv |= VCR_IC_EAV|VCR_IC_EVBI|VCR_IC_FFULL;
317 viacam_write_reg(cam, VCR_INTCTRL, icv);
318 ret = IRQ_WAKE_THREAD;
320 spin_unlock(&cam->viadev->reg_lock);
325 * Find the next videobuf buffer which has somebody waiting on it.
327 static struct videobuf_buffer *viacam_next_buffer(struct via_camera *cam)
330 struct videobuf_buffer *buf = NULL;
332 spin_lock_irqsave(&cam->viadev->reg_lock, flags);
333 if (cam->opstate != S_RUNNING)
335 if (list_empty(&cam->buffer_queue))
337 buf = list_entry(cam->buffer_queue.next, struct videobuf_buffer, queue);
338 if (!waitqueue_active(&buf->done)) {/* Nobody waiting */
342 list_del(&buf->queue);
343 buf->state = VIDEOBUF_ACTIVE;
345 spin_unlock_irqrestore(&cam->viadev->reg_lock, flags);
350 * The threaded IRQ handler.
352 static irqreturn_t viacam_irq(int irq, void *data)
355 struct videobuf_buffer *vb;
356 struct via_camera *cam = data;
357 struct videobuf_dmabuf *vdma;
360 * If there is no place to put the data frame, don't bother
361 * with anything else.
363 vb = viacam_next_buffer(cam);
367 * Figure out which buffer we just completed.
369 bufn = (viacam_read_reg(cam, VCR_INTCTRL) & VCR_IC_ACTBUF) >> 3;
372 bufn = cam->n_cap_bufs - 1;
374 * Copy over the data and let any waiters know.
376 vdma = videobuf_to_dma(vb);
377 viafb_dma_copy_out_sg(cam->cb_offsets[bufn], vdma->sglist, vdma->sglen);
378 vb->state = VIDEOBUF_DONE;
379 vb->size = cam->user_format.sizeimage;
387 * These functions must mess around with the general interrupt
388 * control register, which is relevant to much more than just the
389 * camera. Nothing else uses interrupts, though, as of this writing.
390 * Should that situation change, we'll have to improve support at
391 * the via-core level.
393 static void viacam_int_enable(struct via_camera *cam)
395 viacam_write_reg(cam, VCR_INTCTRL,
396 VCR_IC_INTEN|VCR_IC_EAV|VCR_IC_EVBI|VCR_IC_FFULL);
397 viafb_irq_enable(VDE_I_C0AVEN);
400 static void viacam_int_disable(struct via_camera *cam)
402 viafb_irq_disable(VDE_I_C0AVEN);
403 viacam_write_reg(cam, VCR_INTCTRL, 0);
408 /* --------------------------------------------------------------------------*/
409 /* Controller operations */
412 * Set up our capture buffers in framebuffer memory.
414 static int viacam_ctlr_cbufs(struct via_camera *cam)
416 int nbuf = cam->viadev->camera_fbmem_size/cam->sensor_format.sizeimage;
421 * See how many buffers we can work with.
425 viacam_write_reg_mask(cam, VCR_CAPINTC, VCR_CI_3BUFS,
427 } else if (nbuf == 2) {
429 viacam_write_reg_mask(cam, VCR_CAPINTC, 0, VCR_CI_3BUFS);
431 cam_warn(cam, "Insufficient frame buffer memory\n");
437 offset = cam->fb_offset;
438 for (i = 0; i < cam->n_cap_bufs; i++) {
439 cam->cb_offsets[i] = offset;
440 cam->cb_addrs[i] = cam->fbmem + offset;
441 viacam_write_reg(cam, VCR_VBUF1 + i*4, offset & VCR_VBUF_MASK);
442 offset += cam->sensor_format.sizeimage;
448 * Set the scaling register for downscaling the image.
450 * This register works like this... Vertical scaling is enabled
451 * by bit 26; if that bit is set, downscaling is controlled by the
452 * value in bits 16:25. Those bits are divided by 1024 to get
453 * the scaling factor; setting just bit 25 thus cuts the height
456 * Horizontal scaling works about the same, but it's enabled by
457 * bit 11, with bits 0:10 giving the numerator of a fraction
458 * (over 2048) for the scaling value.
460 * This function is naive in that, if the user departs from
461 * the 3x4 VGA scaling factor, the image will distort. We
462 * could work around that if it really seemed important.
464 static void viacam_set_scale(struct via_camera *cam)
466 unsigned int avscale;
469 if (cam->user_format.width == VGA_WIDTH)
472 sf = (cam->user_format.width*2048)/VGA_WIDTH;
473 avscale = VCR_AVS_HEN | sf;
475 if (cam->user_format.height < VGA_HEIGHT) {
476 sf = (1024*cam->user_format.height)/VGA_HEIGHT;
477 avscale |= VCR_AVS_VEN | (sf << 16);
479 viacam_write_reg(cam, VCR_AVSCALE, avscale);
484 * Configure image-related information into the capture engine.
486 static void viacam_ctlr_image(struct via_camera *cam)
491 * Disable clock before messing with stuff - from the via
494 viacam_write_reg(cam, VCR_CAPINTC, ~(VCR_CI_ENABLE|VCR_CI_CLKEN));
496 * Set up the controller for VGA resolution, modulo magic
497 * offsets from the via sample driver.
499 viacam_write_reg(cam, VCR_HORRANGE, 0x06200120);
500 viacam_write_reg(cam, VCR_VERTRANGE, 0x01de0000);
501 viacam_set_scale(cam);
505 viacam_write_reg(cam, VCR_MAXDATA,
506 (cam->sensor_format.height << 16) |
507 (cam->sensor_format.bytesperline >> 3));
508 viacam_write_reg(cam, VCR_MAXVBI, 0);
509 viacam_write_reg(cam, VCR_VSTRIDE,
510 cam->user_format.bytesperline & VCR_VS_STRIDE);
512 * Set up the capture interface control register,
513 * everything but the "go" bit.
515 * The FIFO threshold is a bit of a magic number; 8 is what
516 * VIA's sample code uses.
518 cicreg = VCR_CI_CLKEN |
519 0x08000000 | /* FIFO threshold */
520 VCR_CI_FLDINV | /* OLPC-specific? */
521 VCR_CI_VREFINV | /* OLPC-specific? */
522 VCR_CI_DIBOTH | /* Capture both fields */
524 if (cam->n_cap_bufs == 3)
525 cicreg |= VCR_CI_3BUFS;
527 * YUV formats need different byte swapping than RGB.
529 if (cam->user_format.pixelformat == V4L2_PIX_FMT_YUYV)
530 cicreg |= VCR_CI_YUYV;
532 cicreg |= VCR_CI_UYVY;
533 viacam_write_reg(cam, VCR_CAPINTC, cicreg);
537 static int viacam_config_controller(struct via_camera *cam)
542 spin_lock_irqsave(&cam->viadev->reg_lock, flags);
543 ret = viacam_ctlr_cbufs(cam);
545 viacam_ctlr_image(cam);
546 spin_unlock_irqrestore(&cam->viadev->reg_lock, flags);
547 clear_bit(CF_CONFIG_NEEDED, &cam->flags);
552 * Make it start grabbing data.
554 static void viacam_start_engine(struct via_camera *cam)
556 spin_lock_irq(&cam->viadev->reg_lock);
558 viacam_write_reg_mask(cam, VCR_CAPINTC, VCR_CI_ENABLE, VCR_CI_ENABLE);
559 viacam_int_enable(cam);
560 (void) viacam_read_reg(cam, VCR_CAPINTC); /* Force post */
561 cam->opstate = S_RUNNING;
562 spin_unlock_irq(&cam->viadev->reg_lock);
566 static void viacam_stop_engine(struct via_camera *cam)
568 spin_lock_irq(&cam->viadev->reg_lock);
569 viacam_int_disable(cam);
570 viacam_write_reg_mask(cam, VCR_CAPINTC, 0, VCR_CI_ENABLE);
571 (void) viacam_read_reg(cam, VCR_CAPINTC); /* Force post */
572 cam->opstate = S_IDLE;
573 spin_unlock_irq(&cam->viadev->reg_lock);
577 /* --------------------------------------------------------------------------*/
578 /* Videobuf callback ops */
581 * buffer_setup. The purpose of this one would appear to be to tell
582 * videobuf how big a single image is. It's also evidently up to us
583 * to put some sort of limit on the maximum number of buffers allowed.
585 static int viacam_vb_buf_setup(struct videobuf_queue *q,
586 unsigned int *count, unsigned int *size)
588 struct via_camera *cam = q->priv_data;
590 *size = cam->user_format.sizeimage;
591 if (*count == 0 || *count > 6) /* Arbitrary number */
599 static int viacam_vb_buf_prepare(struct videobuf_queue *q,
600 struct videobuf_buffer *vb, enum v4l2_field field)
602 struct via_camera *cam = q->priv_data;
604 vb->size = cam->user_format.sizeimage;
605 vb->width = cam->user_format.width; /* bytesperline???? */
606 vb->height = cam->user_format.height;
608 if (vb->state == VIDEOBUF_NEEDS_INIT) {
609 int ret = videobuf_iolock(q, vb, NULL);
613 vb->state = VIDEOBUF_PREPARED;
618 * We've got a buffer to put data into.
620 * FIXME: check for a running engine and valid buffers?
622 static void viacam_vb_buf_queue(struct videobuf_queue *q,
623 struct videobuf_buffer *vb)
625 struct via_camera *cam = q->priv_data;
628 * Note that videobuf holds the lock when it calls
629 * us, so we need not (indeed, cannot) take it here.
631 vb->state = VIDEOBUF_QUEUED;
632 list_add_tail(&vb->queue, &cam->buffer_queue);
638 static void viacam_vb_buf_release(struct videobuf_queue *q,
639 struct videobuf_buffer *vb)
641 struct via_camera *cam = q->priv_data;
643 videobuf_dma_unmap(&cam->platdev->dev, videobuf_to_dma(vb));
644 videobuf_dma_free(videobuf_to_dma(vb));
645 vb->state = VIDEOBUF_NEEDS_INIT;
648 static const struct videobuf_queue_ops viacam_vb_ops = {
649 .buf_setup = viacam_vb_buf_setup,
650 .buf_prepare = viacam_vb_buf_prepare,
651 .buf_queue = viacam_vb_buf_queue,
652 .buf_release = viacam_vb_buf_release,
655 /* --------------------------------------------------------------------------*/
656 /* File operations */
658 static int viacam_open(struct file *filp)
660 struct via_camera *cam = video_drvdata(filp);
662 filp->private_data = cam;
664 * Note the new user. If this is the first one, we'll also
665 * need to power up the sensor.
667 mutex_lock(&cam->lock);
668 if (cam->users == 0) {
669 int ret = viafb_request_dma();
672 mutex_unlock(&cam->lock);
675 via_sensor_power_up(cam);
676 set_bit(CF_CONFIG_NEEDED, &cam->flags);
678 * Hook into videobuf. Evidently this cannot fail.
680 videobuf_queue_sg_init(&cam->vb_queue, &viacam_vb_ops,
681 &cam->platdev->dev, &cam->viadev->reg_lock,
682 V4L2_BUF_TYPE_VIDEO_CAPTURE, V4L2_FIELD_NONE,
683 sizeof(struct videobuf_buffer), cam, NULL);
686 mutex_unlock(&cam->lock);
690 static int viacam_release(struct file *filp)
692 struct via_camera *cam = video_drvdata(filp);
694 mutex_lock(&cam->lock);
697 * If the "owner" is closing, shut down any ongoing
700 if (filp == cam->owner) {
701 videobuf_stop(&cam->vb_queue);
703 * We don't hold the spinlock here, but, if release()
704 * is being called by the owner, nobody else will
705 * be changing the state. And an extra stop would
708 if (cam->opstate != S_IDLE)
709 viacam_stop_engine(cam);
713 * Last one out needs to turn out the lights.
715 if (cam->users == 0) {
716 videobuf_mmap_free(&cam->vb_queue);
717 via_sensor_power_down(cam);
720 mutex_unlock(&cam->lock);
725 * Read a frame from the device.
727 static ssize_t viacam_read(struct file *filp, char __user *buffer,
728 size_t len, loff_t *pos)
730 struct via_camera *cam = video_drvdata(filp);
733 mutex_lock(&cam->lock);
735 * Enforce the V4l2 "only one owner gets to read data" rule.
737 if (cam->owner && cam->owner != filp) {
743 * Do we need to configure the hardware?
745 if (test_bit(CF_CONFIG_NEEDED, &cam->flags)) {
746 ret = viacam_configure_sensor(cam);
748 ret = viacam_config_controller(cam);
753 * Fire up the capture engine, then have videobuf do
754 * the heavy lifting. Someday it would be good to avoid
755 * stopping and restarting the engine each time.
757 INIT_LIST_HEAD(&cam->buffer_queue);
758 viacam_start_engine(cam);
759 ret = videobuf_read_stream(&cam->vb_queue, buffer, len, pos, 0,
760 filp->f_flags & O_NONBLOCK);
761 viacam_stop_engine(cam);
762 /* videobuf_stop() ?? */
765 mutex_unlock(&cam->lock);
770 static unsigned int viacam_poll(struct file *filp, struct poll_table_struct *pt)
772 struct via_camera *cam = video_drvdata(filp);
774 return videobuf_poll_stream(filp, &cam->vb_queue, pt);
778 static int viacam_mmap(struct file *filp, struct vm_area_struct *vma)
780 struct via_camera *cam = video_drvdata(filp);
782 return videobuf_mmap_mapper(&cam->vb_queue, vma);
787 static const struct v4l2_file_operations viacam_fops = {
788 .owner = THIS_MODULE,
790 .release = viacam_release,
794 .unlocked_ioctl = video_ioctl2,
797 /*----------------------------------------------------------------------------*/
799 * The long list of v4l2 ioctl ops
805 static int viacam_enum_input(struct file *filp, void *priv,
806 struct v4l2_input *input)
808 if (input->index != 0)
811 input->type = V4L2_INPUT_TYPE_CAMERA;
812 input->std = V4L2_STD_ALL; /* Not sure what should go here */
813 strcpy(input->name, "Camera");
817 static int viacam_g_input(struct file *filp, void *priv, unsigned int *i)
823 static int viacam_s_input(struct file *filp, void *priv, unsigned int i)
830 static int viacam_s_std(struct file *filp, void *priv, v4l2_std_id std)
835 static int viacam_g_std(struct file *filp, void *priv, v4l2_std_id *std)
837 *std = V4L2_STD_NTSC_M;
842 * Video format stuff. Here is our default format until
843 * user space messes with things.
845 static const struct v4l2_pix_format viacam_def_pix_format = {
847 .height = VGA_HEIGHT,
848 .pixelformat = V4L2_PIX_FMT_YUYV,
849 .field = V4L2_FIELD_NONE,
850 .bytesperline = VGA_WIDTH * 2,
851 .sizeimage = VGA_WIDTH * VGA_HEIGHT * 2,
854 static const u32 via_def_mbus_code = MEDIA_BUS_FMT_YUYV8_2X8;
856 static int viacam_enum_fmt_vid_cap(struct file *filp, void *priv,
857 struct v4l2_fmtdesc *fmt)
859 if (fmt->index >= N_VIA_FMTS)
861 strlcpy(fmt->description, via_formats[fmt->index].desc,
862 sizeof(fmt->description));
863 fmt->pixelformat = via_formats[fmt->index].pixelformat;
868 * Figure out proper image dimensions, but always force the
871 static void viacam_fmt_pre(struct v4l2_pix_format *userfmt,
872 struct v4l2_pix_format *sensorfmt)
874 *sensorfmt = *userfmt;
875 if (userfmt->width < QCIF_WIDTH || userfmt->height < QCIF_HEIGHT) {
876 userfmt->width = QCIF_WIDTH;
877 userfmt->height = QCIF_HEIGHT;
879 if (userfmt->width > VGA_WIDTH || userfmt->height > VGA_HEIGHT) {
880 userfmt->width = VGA_WIDTH;
881 userfmt->height = VGA_HEIGHT;
883 sensorfmt->width = VGA_WIDTH;
884 sensorfmt->height = VGA_HEIGHT;
887 static void viacam_fmt_post(struct v4l2_pix_format *userfmt,
888 struct v4l2_pix_format *sensorfmt)
890 struct via_format *f = via_find_format(userfmt->pixelformat);
892 sensorfmt->bytesperline = sensorfmt->width * f->bpp;
893 sensorfmt->sizeimage = sensorfmt->height * sensorfmt->bytesperline;
894 userfmt->pixelformat = sensorfmt->pixelformat;
895 userfmt->field = sensorfmt->field;
896 userfmt->bytesperline = 2 * userfmt->width;
897 userfmt->sizeimage = userfmt->bytesperline * userfmt->height;
902 * The real work of figuring out a workable format.
904 static int viacam_do_try_fmt(struct via_camera *cam,
905 struct v4l2_pix_format *upix, struct v4l2_pix_format *spix)
908 struct v4l2_subdev_pad_config pad_cfg;
909 struct v4l2_subdev_format format = {
910 .which = V4L2_SUBDEV_FORMAT_TRY,
912 struct via_format *f = via_find_format(upix->pixelformat);
914 upix->pixelformat = f->pixelformat;
915 viacam_fmt_pre(upix, spix);
916 v4l2_fill_mbus_format(&format.format, spix, f->mbus_code);
917 ret = sensor_call(cam, pad, set_fmt, &pad_cfg, &format);
918 v4l2_fill_pix_format(spix, &format.format);
919 viacam_fmt_post(upix, spix);
925 static int viacam_try_fmt_vid_cap(struct file *filp, void *priv,
926 struct v4l2_format *fmt)
928 struct via_camera *cam = priv;
929 struct v4l2_format sfmt;
932 mutex_lock(&cam->lock);
933 ret = viacam_do_try_fmt(cam, &fmt->fmt.pix, &sfmt.fmt.pix);
934 mutex_unlock(&cam->lock);
939 static int viacam_g_fmt_vid_cap(struct file *filp, void *priv,
940 struct v4l2_format *fmt)
942 struct via_camera *cam = priv;
944 mutex_lock(&cam->lock);
945 fmt->fmt.pix = cam->user_format;
946 mutex_unlock(&cam->lock);
950 static int viacam_s_fmt_vid_cap(struct file *filp, void *priv,
951 struct v4l2_format *fmt)
953 struct via_camera *cam = priv;
955 struct v4l2_format sfmt;
956 struct via_format *f = via_find_format(fmt->fmt.pix.pixelformat);
959 * Camera must be idle or we can't mess with the
962 mutex_lock(&cam->lock);
963 if (cam->opstate != S_IDLE) {
968 * Let the sensor code look over and tweak the
969 * requested formatting.
971 ret = viacam_do_try_fmt(cam, &fmt->fmt.pix, &sfmt.fmt.pix);
975 * OK, let's commit to the new format.
977 cam->user_format = fmt->fmt.pix;
978 cam->sensor_format = sfmt.fmt.pix;
979 cam->mbus_code = f->mbus_code;
980 ret = viacam_configure_sensor(cam);
982 ret = viacam_config_controller(cam);
984 mutex_unlock(&cam->lock);
988 static int viacam_querycap(struct file *filp, void *priv,
989 struct v4l2_capability *cap)
991 strcpy(cap->driver, "via-camera");
992 strcpy(cap->card, "via-camera");
993 cap->device_caps = V4L2_CAP_VIDEO_CAPTURE |
994 V4L2_CAP_READWRITE | V4L2_CAP_STREAMING;
995 cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
1000 * Streaming operations - pure videobuf stuff.
1002 static int viacam_reqbufs(struct file *filp, void *priv,
1003 struct v4l2_requestbuffers *rb)
1005 struct via_camera *cam = priv;
1007 return videobuf_reqbufs(&cam->vb_queue, rb);
1010 static int viacam_querybuf(struct file *filp, void *priv,
1011 struct v4l2_buffer *buf)
1013 struct via_camera *cam = priv;
1015 return videobuf_querybuf(&cam->vb_queue, buf);
1018 static int viacam_qbuf(struct file *filp, void *priv, struct v4l2_buffer *buf)
1020 struct via_camera *cam = priv;
1022 return videobuf_qbuf(&cam->vb_queue, buf);
1025 static int viacam_dqbuf(struct file *filp, void *priv, struct v4l2_buffer *buf)
1027 struct via_camera *cam = priv;
1029 return videobuf_dqbuf(&cam->vb_queue, buf, filp->f_flags & O_NONBLOCK);
1032 static int viacam_streamon(struct file *filp, void *priv, enum v4l2_buf_type t)
1034 struct via_camera *cam = priv;
1037 if (t != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1040 mutex_lock(&cam->lock);
1041 if (cam->opstate != S_IDLE) {
1046 * Enforce the V4l2 "only one owner gets to read data" rule.
1048 if (cam->owner && cam->owner != filp) {
1054 * Configure things if need be.
1056 if (test_bit(CF_CONFIG_NEEDED, &cam->flags)) {
1057 ret = viacam_configure_sensor(cam);
1060 ret = viacam_config_controller(cam);
1065 * If the CPU goes into C3, the DMA transfer gets corrupted and
1066 * users start filing unsightly bug reports. Put in a "latency"
1067 * requirement which will keep the CPU out of the deeper sleep
1070 pm_qos_add_request(&cam->qos_request, PM_QOS_CPU_DMA_LATENCY, 50);
1074 INIT_LIST_HEAD(&cam->buffer_queue);
1075 ret = videobuf_streamon(&cam->vb_queue);
1077 viacam_start_engine(cam);
1079 mutex_unlock(&cam->lock);
1083 static int viacam_streamoff(struct file *filp, void *priv, enum v4l2_buf_type t)
1085 struct via_camera *cam = priv;
1088 if (t != V4L2_BUF_TYPE_VIDEO_CAPTURE)
1090 mutex_lock(&cam->lock);
1091 if (cam->opstate != S_RUNNING) {
1095 pm_qos_remove_request(&cam->qos_request);
1096 viacam_stop_engine(cam);
1098 * Videobuf will recycle all of the outstanding buffers, but
1099 * we should be sure we don't retain any references to
1102 ret = videobuf_streamoff(&cam->vb_queue);
1103 INIT_LIST_HEAD(&cam->buffer_queue);
1105 mutex_unlock(&cam->lock);
1111 static int viacam_g_parm(struct file *filp, void *priv,
1112 struct v4l2_streamparm *parm)
1114 struct via_camera *cam = priv;
1117 mutex_lock(&cam->lock);
1118 ret = sensor_call(cam, video, g_parm, parm);
1119 mutex_unlock(&cam->lock);
1120 parm->parm.capture.readbuffers = cam->n_cap_bufs;
1124 static int viacam_s_parm(struct file *filp, void *priv,
1125 struct v4l2_streamparm *parm)
1127 struct via_camera *cam = priv;
1130 mutex_lock(&cam->lock);
1131 ret = sensor_call(cam, video, s_parm, parm);
1132 mutex_unlock(&cam->lock);
1133 parm->parm.capture.readbuffers = cam->n_cap_bufs;
1137 static int viacam_enum_framesizes(struct file *filp, void *priv,
1138 struct v4l2_frmsizeenum *sizes)
1140 if (sizes->index != 0)
1142 sizes->type = V4L2_FRMSIZE_TYPE_CONTINUOUS;
1143 sizes->stepwise.min_width = QCIF_WIDTH;
1144 sizes->stepwise.min_height = QCIF_HEIGHT;
1145 sizes->stepwise.max_width = VGA_WIDTH;
1146 sizes->stepwise.max_height = VGA_HEIGHT;
1147 sizes->stepwise.step_width = sizes->stepwise.step_height = 1;
1151 static int viacam_enum_frameintervals(struct file *filp, void *priv,
1152 struct v4l2_frmivalenum *interval)
1154 struct via_camera *cam = priv;
1155 struct v4l2_subdev_frame_interval_enum fie = {
1156 .index = interval->index,
1157 .code = cam->mbus_code,
1158 .width = cam->sensor_format.width,
1159 .height = cam->sensor_format.height,
1160 .which = V4L2_SUBDEV_FORMAT_ACTIVE,
1164 mutex_lock(&cam->lock);
1165 ret = sensor_call(cam, pad, enum_frame_interval, NULL, &fie);
1166 mutex_unlock(&cam->lock);
1169 interval->type = V4L2_FRMIVAL_TYPE_DISCRETE;
1170 interval->discrete = fie.interval;
1176 static const struct v4l2_ioctl_ops viacam_ioctl_ops = {
1177 .vidioc_enum_input = viacam_enum_input,
1178 .vidioc_g_input = viacam_g_input,
1179 .vidioc_s_input = viacam_s_input,
1180 .vidioc_s_std = viacam_s_std,
1181 .vidioc_g_std = viacam_g_std,
1182 .vidioc_enum_fmt_vid_cap = viacam_enum_fmt_vid_cap,
1183 .vidioc_try_fmt_vid_cap = viacam_try_fmt_vid_cap,
1184 .vidioc_g_fmt_vid_cap = viacam_g_fmt_vid_cap,
1185 .vidioc_s_fmt_vid_cap = viacam_s_fmt_vid_cap,
1186 .vidioc_querycap = viacam_querycap,
1187 .vidioc_reqbufs = viacam_reqbufs,
1188 .vidioc_querybuf = viacam_querybuf,
1189 .vidioc_qbuf = viacam_qbuf,
1190 .vidioc_dqbuf = viacam_dqbuf,
1191 .vidioc_streamon = viacam_streamon,
1192 .vidioc_streamoff = viacam_streamoff,
1193 .vidioc_g_parm = viacam_g_parm,
1194 .vidioc_s_parm = viacam_s_parm,
1195 .vidioc_enum_framesizes = viacam_enum_framesizes,
1196 .vidioc_enum_frameintervals = viacam_enum_frameintervals,
1199 /*----------------------------------------------------------------------------*/
1206 static int viacam_suspend(void *priv)
1208 struct via_camera *cam = priv;
1209 enum viacam_opstate state = cam->opstate;
1211 if (cam->opstate != S_IDLE) {
1212 viacam_stop_engine(cam);
1213 cam->opstate = state; /* So resume restarts */
1219 static int viacam_resume(void *priv)
1221 struct via_camera *cam = priv;
1225 * Get back to a reasonable operating state.
1227 via_write_reg_mask(VIASR, 0x78, 0, 0x80);
1228 via_write_reg_mask(VIASR, 0x1e, 0xc0, 0xc0);
1229 viacam_int_disable(cam);
1230 set_bit(CF_CONFIG_NEEDED, &cam->flags);
1232 * Make sure the sensor's power state is correct
1235 via_sensor_power_up(cam);
1237 via_sensor_power_down(cam);
1239 * If it was operating, try to restart it.
1241 if (cam->opstate != S_IDLE) {
1242 mutex_lock(&cam->lock);
1243 ret = viacam_configure_sensor(cam);
1245 ret = viacam_config_controller(cam);
1246 mutex_unlock(&cam->lock);
1248 viacam_start_engine(cam);
1254 static struct viafb_pm_hooks viacam_pm_hooks = {
1255 .suspend = viacam_suspend,
1256 .resume = viacam_resume
1259 #endif /* CONFIG_PM */
1265 static struct video_device viacam_v4l_template = {
1266 .name = "via-camera",
1268 .tvnorms = V4L2_STD_NTSC_M,
1269 .fops = &viacam_fops,
1270 .ioctl_ops = &viacam_ioctl_ops,
1271 .release = video_device_release_empty, /* Check this */
1275 * The OLPC folks put the serial port on the same pin as
1276 * the camera. They also get grumpy if we break the
1277 * serial port and keep them from using it. So we have
1278 * to check the serial enable bit and not step on it.
1280 #define VIACAM_SERIAL_DEVFN 0x88
1281 #define VIACAM_SERIAL_CREG 0x46
1282 #define VIACAM_SERIAL_BIT 0x40
1284 static bool viacam_serial_is_enabled(void)
1286 struct pci_bus *pbus = pci_find_bus(0, 0);
1291 pci_bus_read_config_byte(pbus, VIACAM_SERIAL_DEVFN,
1292 VIACAM_SERIAL_CREG, &cbyte);
1293 if ((cbyte & VIACAM_SERIAL_BIT) == 0)
1294 return false; /* Not enabled */
1295 if (!override_serial) {
1296 printk(KERN_NOTICE "Via camera: serial port is enabled, " \
1297 "refusing to load.\n");
1298 printk(KERN_NOTICE "Specify override_serial=1 to force " \
1299 "module loading.\n");
1302 printk(KERN_NOTICE "Via camera: overriding serial port\n");
1303 pci_bus_write_config_byte(pbus, VIACAM_SERIAL_DEVFN,
1304 VIACAM_SERIAL_CREG, cbyte & ~VIACAM_SERIAL_BIT);
1308 static struct ov7670_config sensor_cfg = {
1309 /* The XO-1.5 (only known user) clocks the camera at 90MHz. */
1313 static int viacam_probe(struct platform_device *pdev)
1316 struct i2c_adapter *sensor_adapter;
1317 struct viafb_dev *viadev = pdev->dev.platform_data;
1318 struct i2c_board_info ov7670_info = {
1321 .platform_data = &sensor_cfg,
1325 * Note that there are actually two capture channels on
1326 * the device. We only deal with one for now. That
1327 * is encoded here; nothing else assumes it's dealing with
1328 * a unique capture device.
1330 struct via_camera *cam;
1333 * Ensure that frame buffer memory has been set aside for
1334 * this purpose. As an arbitrary limit, refuse to work
1335 * with less than two frames of VGA 16-bit data.
1337 * If we ever support the second port, we'll need to set
1338 * aside more memory.
1340 if (viadev->camera_fbmem_size < (VGA_HEIGHT*VGA_WIDTH*4)) {
1341 printk(KERN_ERR "viacam: insufficient FB memory reserved\n");
1344 if (viadev->engine_mmio == NULL) {
1345 printk(KERN_ERR "viacam: No I/O memory, so no pictures\n");
1349 if (machine_is_olpc() && viacam_serial_is_enabled())
1353 * Basic structure initialization.
1355 cam = kzalloc (sizeof(struct via_camera), GFP_KERNEL);
1359 cam->platdev = pdev;
1360 cam->viadev = viadev;
1363 cam->opstate = S_IDLE;
1364 cam->user_format = cam->sensor_format = viacam_def_pix_format;
1365 mutex_init(&cam->lock);
1366 INIT_LIST_HEAD(&cam->buffer_queue);
1367 cam->mmio = viadev->engine_mmio;
1368 cam->fbmem = viadev->fbmem;
1369 cam->fb_offset = viadev->camera_fbmem_offset;
1370 cam->flags = 1 << CF_CONFIG_NEEDED;
1371 cam->mbus_code = via_def_mbus_code;
1373 * Tell V4L that we exist.
1375 ret = v4l2_device_register(&pdev->dev, &cam->v4l2_dev);
1377 dev_err(&pdev->dev, "Unable to register v4l2 device\n");
1380 ret = v4l2_ctrl_handler_init(&cam->ctrl_handler, 10);
1382 goto out_unregister;
1383 cam->v4l2_dev.ctrl_handler = &cam->ctrl_handler;
1385 * Convince the system that we can do DMA.
1387 pdev->dev.dma_mask = &viadev->pdev->dma_mask;
1388 dma_set_mask(&pdev->dev, 0xffffffff);
1390 * Fire up the capture port. The write to 0x78 looks purely
1391 * OLPCish; any system will need to tweak 0x1e.
1393 via_write_reg_mask(VIASR, 0x78, 0, 0x80);
1394 via_write_reg_mask(VIASR, 0x1e, 0xc0, 0xc0);
1396 * Get the sensor powered up.
1398 ret = via_sensor_power_setup(cam);
1400 goto out_ctrl_hdl_free;
1401 via_sensor_power_up(cam);
1404 * See if we can't find it on the bus. The VIA_PORT_31 assumption
1405 * is OLPC-specific. 0x42 assumption is ov7670-specific.
1407 sensor_adapter = viafb_find_i2c_adapter(VIA_PORT_31);
1408 cam->sensor = v4l2_i2c_new_subdev_board(&cam->v4l2_dev, sensor_adapter,
1409 &ov7670_info, NULL);
1410 if (cam->sensor == NULL) {
1411 dev_err(&pdev->dev, "Unable to find the sensor!\n");
1413 goto out_power_down;
1418 viacam_int_disable(cam);
1419 ret = request_threaded_irq(viadev->pdev->irq, viacam_quick_irq,
1420 viacam_irq, IRQF_SHARED, "via-camera", cam);
1422 goto out_power_down;
1424 * Tell V4l2 that we exist.
1426 cam->vdev = viacam_v4l_template;
1427 cam->vdev.v4l2_dev = &cam->v4l2_dev;
1428 ret = video_register_device(&cam->vdev, VFL_TYPE_GRABBER, -1);
1431 video_set_drvdata(&cam->vdev, cam);
1435 * Hook into PM events
1437 viacam_pm_hooks.private = cam;
1438 viafb_pm_register(&viacam_pm_hooks);
1441 /* Power the sensor down until somebody opens the device */
1442 via_sensor_power_down(cam);
1446 free_irq(viadev->pdev->irq, cam);
1448 via_sensor_power_release(cam);
1450 v4l2_ctrl_handler_free(&cam->ctrl_handler);
1452 v4l2_device_unregister(&cam->v4l2_dev);
1458 static int viacam_remove(struct platform_device *pdev)
1460 struct via_camera *cam = via_cam_info;
1461 struct viafb_dev *viadev = pdev->dev.platform_data;
1463 video_unregister_device(&cam->vdev);
1464 v4l2_device_unregister(&cam->v4l2_dev);
1465 free_irq(viadev->pdev->irq, cam);
1466 via_sensor_power_release(cam);
1467 v4l2_ctrl_handler_free(&cam->ctrl_handler);
1469 via_cam_info = NULL;
1473 static struct platform_driver viacam_driver = {
1475 .name = "viafb-camera",
1477 .probe = viacam_probe,
1478 .remove = viacam_remove,
1481 module_platform_driver(viacam_driver);