diff options
| -rw-r--r-- | drivers/media/video/pxa_camera.c | 15 | ||||
| -rw-r--r-- | drivers/media/video/sh_mobile_ceu_camera.c | 9 | ||||
| -rw-r--r-- | drivers/media/video/soc_camera.c | 99 | ||||
| -rw-r--r-- | include/media/soc_camera.h | 8 |
4 files changed, 96 insertions, 35 deletions
diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c index aa7efc45d364..c3c50de0aa50 100644 --- a/drivers/media/video/pxa_camera.c +++ b/drivers/media/video/pxa_camera.c @@ -25,7 +25,6 @@ #include <linux/version.h> #include <linux/device.h> #include <linux/platform_device.h> -#include <linux/mutex.h> #include <linux/clk.h> #include <media/v4l2-common.h> @@ -164,8 +163,6 @@ CICR0_PERRM | CICR0_QDM | CICR0_CDM | CICR0_SOFM | \ CICR0_EOFM | CICR0_FOM) -static DEFINE_MUTEX(camera_lock); - /* * Structures */ @@ -813,16 +810,17 @@ static irqreturn_t pxa_camera_irq(int irq, void *data) return IRQ_HANDLED; } -/* The following two functions absolutely depend on the fact, that - * there can be only one camera on PXA quick capture interface */ +/* + * The following two functions absolutely depend on the fact, that + * there can be only one camera on PXA quick capture interface + * Called with .video_lock held + */ static int pxa_camera_add_device(struct soc_camera_device *icd) { struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); struct pxa_camera_dev *pcdev = ici->priv; int ret; - mutex_lock(&camera_lock); - if (pcdev->icd) { ret = -EBUSY; goto ebusy; @@ -838,11 +836,10 @@ static int pxa_camera_add_device(struct soc_camera_device *icd) pcdev->icd = icd; ebusy: - mutex_unlock(&camera_lock); - return ret; } +/* Called with .video_lock held */ static void pxa_camera_remove_device(struct soc_camera_device *icd) { struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); diff --git a/drivers/media/video/sh_mobile_ceu_camera.c b/drivers/media/video/sh_mobile_ceu_camera.c index a49bec1509f4..47ffa441c869 100644 --- a/drivers/media/video/sh_mobile_ceu_camera.c +++ b/drivers/media/video/sh_mobile_ceu_camera.c @@ -29,7 +29,6 @@ #include <linux/version.h> #include <linux/device.h> #include <linux/platform_device.h> -#include <linux/mutex.h> #include <linux/videodev2.h> #include <linux/clk.h> @@ -75,8 +74,6 @@ #define CDBYR2 0x98 /* Capture data bottom-field address Y register 2 */ #define CDBCR2 0x9c /* Capture data bottom-field address C register 2 */ -static DEFINE_MUTEX(camera_lock); - /* per video frame buffer */ struct sh_mobile_ceu_buffer { struct videobuf_buffer vb; /* v4l buffer must be first */ @@ -292,14 +289,13 @@ static irqreturn_t sh_mobile_ceu_irq(int irq, void *data) return IRQ_HANDLED; } +/* Called with .video_lock held */ static int sh_mobile_ceu_add_device(struct soc_camera_device *icd) { struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); struct sh_mobile_ceu_dev *pcdev = ici->priv; int ret = -EBUSY; - mutex_lock(&camera_lock); - if (pcdev->icd) goto err; @@ -319,11 +315,10 @@ static int sh_mobile_ceu_add_device(struct soc_camera_device *icd) pcdev->icd = icd; err: - mutex_unlock(&camera_lock); - return ret; } +/* Called with .video_lock held */ static void sh_mobile_ceu_remove_device(struct soc_camera_device *icd) { struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); diff --git a/drivers/media/video/soc_camera.c b/drivers/media/video/soc_camera.c index d5613cdd93a6..e869670dbae5 100644 --- a/drivers/media/video/soc_camera.c +++ b/drivers/media/video/soc_camera.c @@ -33,7 +33,6 @@ static LIST_HEAD(hosts); static LIST_HEAD(devices); static DEFINE_MUTEX(list_lock); -static DEFINE_MUTEX(video_lock); const struct soc_camera_data_format *soc_camera_format_by_fourcc( struct soc_camera_device *icd, unsigned int fourcc) @@ -270,8 +269,10 @@ static int soc_camera_open(struct inode *inode, struct file *file) if (!icf) return -ENOMEM; - /* Protect against icd->remove() until we module_get() both drivers. */ - mutex_lock(&video_lock); + /* + * It is safe to dereference these pointers now as long as a user has + * the video device open - we are protected by the held cdev reference. + */ vdev = video_devdata(file); icd = container_of(vdev->parent, struct soc_camera_device, dev); @@ -289,6 +290,9 @@ static int soc_camera_open(struct inode *inode, struct file *file) goto emgi; } + /* Protect against icd->remove() until we module_get() both drivers. */ + mutex_lock(&icd->video_lock); + icf->icd = icd; icd->use_count++; @@ -304,7 +308,7 @@ static int soc_camera_open(struct inode *inode, struct file *file) } } - mutex_unlock(&video_lock); + mutex_unlock(&icd->video_lock); file->private_data = icf; dev_dbg(&icd->dev, "camera device open\n"); @@ -313,16 +317,16 @@ static int soc_camera_open(struct inode *inode, struct file *file) return 0; - /* All errors are entered with the video_lock held */ + /* First two errors are entered with the .video_lock held */ eiciadd: soc_camera_free_user_formats(icd); eiufmt: icd->use_count--; + mutex_unlock(&icd->video_lock); module_put(ici->ops->owner); emgi: module_put(icd->ops->owner); emgd: - mutex_unlock(&video_lock); vfree(icf); return ret; } @@ -334,15 +338,16 @@ static int soc_camera_close(struct inode *inode, struct file *file) struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); struct video_device *vdev = icd->vdev; - mutex_lock(&video_lock); + mutex_lock(&icd->video_lock); icd->use_count--; if (!icd->use_count) { ici->ops->remove(icd); soc_camera_free_user_formats(icd); } + mutex_unlock(&icd->video_lock); + module_put(icd->ops->owner); module_put(ici->ops->owner); - mutex_unlock(&video_lock); vfree(icf); @@ -424,18 +429,27 @@ static int soc_camera_s_fmt_vid_cap(struct file *file, void *priv, if (ret < 0) return ret; + mutex_lock(&icf->vb_vidq.vb_lock); + + if (videobuf_queue_is_busy(&icf->vb_vidq)) { + dev_err(&icd->dev, "S_FMT denied: queue busy\n"); + ret = -EBUSY; + goto unlock; + } + rect.left = icd->x_current; rect.top = icd->y_current; rect.width = pix->width; rect.height = pix->height; ret = ici->ops->set_fmt(icd, pix->pixelformat, &rect); if (ret < 0) { - return ret; + goto unlock; } else if (!icd->current_fmt || icd->current_fmt->fourcc != pixfmt) { dev_err(&ici->dev, "Host driver hasn't set up current format correctly!\n"); - return -EINVAL; + ret = -EINVAL; + goto unlock; } icd->width = rect.width; @@ -449,7 +463,12 @@ static int soc_camera_s_fmt_vid_cap(struct file *file, void *priv, icd->width, icd->height); /* set physical bus parameters */ - return ici->ops->set_bus_param(icd, pixfmt); + ret = ici->ops->set_bus_param(icd, pixfmt); + +unlock: + mutex_unlock(&icf->vb_vidq.vb_lock); + + return ret; } static int soc_camera_enum_fmt_vid_cap(struct file *file, void *priv, @@ -510,6 +529,7 @@ static int soc_camera_streamon(struct file *file, void *priv, { struct soc_camera_file *icf = file->private_data; struct soc_camera_device *icd = icf->icd; + int ret; WARN_ON(priv != file->private_data); @@ -518,10 +538,16 @@ static int soc_camera_streamon(struct file *file, void *priv, if (i != V4L2_BUF_TYPE_VIDEO_CAPTURE) return -EINVAL; + mutex_lock(&icd->video_lock); + icd->ops->start_capture(icd); /* This calls buf_queue from host driver's videobuf_queue_ops */ - return videobuf_streamon(&icf->vb_vidq); + ret = videobuf_streamon(&icf->vb_vidq); + + mutex_unlock(&icd->video_lock); + + return ret; } static int soc_camera_streamoff(struct file *file, void *priv, @@ -537,12 +563,16 @@ static int soc_camera_streamoff(struct file *file, void *priv, if (i != V4L2_BUF_TYPE_VIDEO_CAPTURE) return -EINVAL; + mutex_lock(&icd->video_lock); + /* This calls buf_release from host driver's videobuf_queue_ops for all * remaining buffers. When the last buffer is freed, stop capture */ videobuf_streamoff(&icf->vb_vidq); icd->ops->stop_capture(icd); + mutex_unlock(&icd->video_lock); + return 0; } @@ -654,6 +684,9 @@ static int soc_camera_s_crop(struct file *file, void *fh, if (a->type != V4L2_BUF_TYPE_VIDEO_CAPTURE) return -EINVAL; + /* Cropping is allowed during a running capture, guard consistency */ + mutex_lock(&icf->vb_vidq.vb_lock); + ret = ici->ops->set_fmt(icd, 0, &a->c); if (!ret) { icd->width = a->c.width; @@ -662,6 +695,8 @@ static int soc_camera_s_crop(struct file *file, void *fh, icd->y_current = a->c.top; } + mutex_unlock(&icf->vb_vidq.vb_lock); + return ret; } @@ -775,11 +810,32 @@ static int soc_camera_probe(struct device *dev) struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); int ret; + /* + * Possible race scenario: + * modprobe <camera-host-driver> triggers __func__ + * at this moment respective <camera-sensor-driver> gets rmmod'ed + * to protect take module references. + */ + + if (!try_module_get(icd->ops->owner)) { + dev_err(&icd->dev, "Couldn't lock sensor driver.\n"); + ret = -EINVAL; + goto emgd; + } + + if (!try_module_get(ici->ops->owner)) { + dev_err(&icd->dev, "Couldn't lock capture bus driver.\n"); + ret = -EINVAL; + goto emgi; + } + + mutex_lock(&icd->video_lock); + /* We only call ->add() here to activate and probe the camera. * We shall ->remove() and deactivate it immediately afterwards. */ ret = ici->ops->add(icd); if (ret < 0) - return ret; + goto eiadd; ret = icd->ops->probe(icd); if (ret >= 0) { @@ -793,6 +849,12 @@ static int soc_camera_probe(struct device *dev) } ici->ops->remove(icd); +eiadd: + mutex_unlock(&icd->video_lock); + module_put(ici->ops->owner); +emgi: + module_put(icd->ops->owner); +emgd: return ret; } @@ -966,6 +1028,7 @@ int soc_camera_device_register(struct soc_camera_device *icd) icd->dev.release = dummy_release; icd->use_count = 0; icd->host_priv = NULL; + mutex_init(&icd->video_lock); return scan_add_device(icd); } @@ -1012,6 +1075,10 @@ static const struct v4l2_ioctl_ops soc_camera_ioctl_ops = { #endif }; +/* + * Usually called from the struct soc_camera_ops .probe() method, i.e., from + * soc_camera_probe() above with .video_lock held + */ int soc_camera_video_start(struct soc_camera_device *icd) { struct soc_camera_host *ici = to_soc_camera_host(icd->dev.parent); @@ -1027,7 +1094,7 @@ int soc_camera_video_start(struct soc_camera_device *icd) dev_dbg(&ici->dev, "Allocated video_device %p\n", vdev); strlcpy(vdev->name, ici->drv_name, sizeof(vdev->name)); - /* Maybe better &ici->dev */ + vdev->parent = &icd->dev; vdev->current_norm = V4L2_STD_UNKNOWN; vdev->fops = &soc_camera_fops; @@ -1061,10 +1128,10 @@ void soc_camera_video_stop(struct soc_camera_device *icd) if (!icd->dev.parent || !vdev) return; - mutex_lock(&video_lock); + mutex_lock(&icd->video_lock); video_unregister_device(vdev); icd->vdev = NULL; - mutex_unlock(&video_lock); + mutex_unlock(&icd->video_lock); } EXPORT_SYMBOL(soc_camera_video_stop); diff --git a/include/media/soc_camera.h b/include/media/soc_camera.h index 38b826c608be..8bae9a359d93 100644 --- a/include/media/soc_camera.h +++ b/include/media/soc_camera.h @@ -12,9 +12,10 @@ #ifndef SOC_CAMERA_H #define SOC_CAMERA_H +#include <linux/mutex.h> +#include <linux/pm.h> #include <linux/videodev2.h> #include <media/videobuf-core.h> -#include <linux/pm.h> struct soc_camera_device { struct list_head list; @@ -45,9 +46,10 @@ struct soc_camera_device { struct soc_camera_format_xlate *user_formats; int num_user_formats; struct module *owner; - void *host_priv; /* per-device host private data */ - /* soc_camera.c private count. Only accessed with video_lock held */ + void *host_priv; /* Per-device host private data */ + /* soc_camera.c private count. Only accessed with .video_lock held */ int use_count; + struct mutex video_lock; /* Protects device data */ }; struct soc_camera_file { |