[PATCH v10 18/21] soc-camera: add V4L2-async support

Guennadi Liakhovetski
2013-06-11T09:28:01Z

Add support for asynchronous subdevice probing, using the v4l2-async API.
The legacy synchronous mode is still supported too, which allows to
gradually update drivers and platforms. The selected approach adds a
notifier for each struct soc_camera_device instance, i.e. for each video
device node, even when there are multiple such instances registered with a
single soc-camera host simultaneously.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
---
drivers/media/platform/soc_camera/soc_camera.c | 527 ++++++++++++++++++++----
include/media/soc_camera.h | 23 +-
2 files changed, 464 insertions(+), 86 deletions(-)

diff --git a/drivers/media/platform/soc_camera/soc_camera.c b/drivers/media/platform/soc_camera/soc_camera.c
index 5845916..725e49d 100644
--- a/drivers/media/platform/soc_camera/soc_camera.c
+++ b/drivers/media/platform/soc_camera/soc_camera.c
@@ -21,22 +21,23 @@
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/list.h>
-#include <linux/mutex.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
-#include <linux/pm_runtime.h>
#include <linux/vmalloc.h>

#include <media/soc_camera.h>
+#include <media/soc_mediabus.h>
+#include <media/v4l2-async.h>
#include <media/v4l2-clk.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <media/v4l2-dev.h>
#include <media/videobuf-core.h>
#include <media/videobuf2-core.h>
-#include <media/soc_mediabus.h>

/* Default to VGA resolution */
#define DEFAULT_WIDTH 640
@@ -47,23 +48,39 @@
(icd)->vb_vidq.streaming : \
vb2_is_streaming(&(icd)->vb2_vidq))

+#define MAP_MAX_NUM 32
+static DECLARE_BITMAP(device_map, MAP_MAX_NUM);
static LIST_HEAD(hosts);
static LIST_HEAD(devices);
-static DEFINE_MUTEX(list_lock); /* Protects the list of hosts */
+/*
+ * Protects lists and bitmaps of hosts and devices.
+ * Lock nesting: Ok to take ->host_lock under list_lock.
+ */
+static DEFINE_MUTEX(list_lock);
+
+struct soc_camera_async_client {
+ struct v4l2_async_subdev *sensor;
+ struct v4l2_async_notifier notifier;
+ struct platform_device *pdev;
+ struct list_head list; /* needed for clean up */
+};
+
+static int soc_camera_video_start(struct soc_camera_device *icd);
+static int video_dev_create(struct soc_camera_device *icd);

int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd,
struct v4l2_clk *clk)
{
int ret = clk ? v4l2_clk_enable(clk) : 0;
if (ret < 0) {
- dev_err(dev, "Cannot enable clock\n");
+ dev_err(dev, "Cannot enable clock: %d\n", ret);
return ret;
}
ret = regulator_bulk_enable(ssdd->num_regulators,
ssdd->regulators);
if (ret < 0) {
dev_err(dev, "Cannot enable regulators\n");
- goto eregenable;;
+ goto eregenable;
}

if (ssdd->power) {
@@ -117,6 +134,14 @@ int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd
}
EXPORT_SYMBOL(soc_camera_power_off);

+int soc_camera_power_init(struct device *dev, struct soc_camera_subdev_desc *ssdd)
+{
+
+ return devm_regulator_bulk_get(dev, ssdd->num_regulators,
+ ssdd->regulators);
+}
+EXPORT_SYMBOL(soc_camera_power_init);
+
static int __soc_camera_power_on(struct soc_camera_device *icd)
{
struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
@@ -533,7 +558,9 @@ static int soc_camera_add_device(struct soc_camera_device *icd)
return -EBUSY;

if (!icd->clk) {
+ mutex_lock(&ici->clk_lock);
ret = ici->ops->clock_start(ici);
+ mutex_unlock(&ici->clk_lock);
if (ret < 0)
return ret;
}
@@ -549,8 +576,11 @@ static int soc_camera_add_device(struct soc_camera_device *icd)
return 0;

eadd:
- if (!icd->clk)
+ if (!icd->clk) {
+ mutex_lock(&ici->clk_lock);
ici->ops->clock_stop(ici);
+ mutex_unlock(&ici->clk_lock);
+ }
return ret;
}

@@ -563,8 +593,11 @@ static void soc_camera_remove_device(struct soc_camera_device *icd)

if (ici->ops->remove)
ici->ops->remove(icd);
- if (!icd->clk)
+ if (!icd->clk) {
+ mutex_lock(&ici->clk_lock);
ici->ops->clock_stop(ici);
+ mutex_unlock(&ici->clk_lock);
+ }
ici->icd = NULL;
}

@@ -673,8 +706,8 @@ static int soc_camera_open(struct file *file)
return 0;

/*
- * First four errors are entered with the .host_lock held
- * and use_count == 1
+ * All errors are entered with the .host_lock held, first four also
+ * with use_count == 1
*/
einitvb:
esfmt:
@@ -1128,7 +1161,8 @@ static int soc_camera_s_register(struct file *file, void *fh,
}
#endif

-static int soc_camera_probe(struct soc_camera_device *icd);
+static int soc_camera_probe(struct soc_camera_host *ici,
+ struct soc_camera_device *icd);

/* So far this function cannot fail */
static void scan_add_host(struct soc_camera_host *ici)
@@ -1137,12 +1171,20 @@ static void scan_add_host(struct soc_camera_host *ici)

mutex_lock(&list_lock);

- list_for_each_entry(icd, &devices, list) {
+ list_for_each_entry(icd, &devices, list)
if (icd->iface == ici->nr) {
+ struct soc_camera_desc *sdesc = to_soc_camera_desc(icd);
+ struct soc_camera_subdev_desc *ssdd = &sdesc->subdev_desc;
+
+ /* The camera could have been already on, try to reset */
+ if (ssdd->reset)
+ ssdd->reset(icd->pdev);
+
icd->parent = ici->v4l2_dev.dev;
- soc_camera_probe(icd);
+
+ /* Ignore errors */
+ soc_camera_probe(ici, icd);
}
- }

mutex_unlock(&list_lock);
}
@@ -1155,6 +1197,7 @@ static int soc_camera_clk_enable(struct v4l2_clk *clk)
{
struct soc_camera_device *icd = clk->priv;
struct soc_camera_host *ici;
+ int ret;

if (!icd || !icd->parent)
return -ENODEV;
@@ -1168,7 +1211,10 @@ static int soc_camera_clk_enable(struct v4l2_clk *clk)
* If a different client is currently being probed, the host will tell
* you to go
*/
- return ici->ops->clock_start(ici);
+ mutex_lock(&ici->clk_lock);
+ ret = ici->ops->clock_start(ici);
+ mutex_unlock(&ici->clk_lock);
+ return ret;
}

static void soc_camera_clk_disable(struct v4l2_clk *clk)
@@ -1181,7 +1227,9 @@ static void soc_camera_clk_disable(struct v4l2_clk *clk)

ici = to_soc_camera_host(icd->parent);

+ mutex_lock(&ici->clk_lock);
ici->ops->clock_stop(ici);
+ mutex_unlock(&ici->clk_lock);

module_put(ici->ops->owner);
}
@@ -1198,18 +1246,117 @@ static const struct v4l2_clk_ops soc_camera_clk_ops = {
.disable = soc_camera_clk_disable,
};

+static int soc_camera_dyn_pdev(struct soc_camera_desc *sdesc,
+ struct soc_camera_async_client *sasc)
+{
+ struct platform_device *pdev;
+ int ret, i;
+
+ mutex_lock(&list_lock);
+ i = find_first_zero_bit(device_map, MAP_MAX_NUM);
+ if (i < MAP_MAX_NUM)
+ set_bit(i, device_map);
+ mutex_unlock(&list_lock);
+ if (i >= MAP_MAX_NUM)
+ return -ENOMEM;
+
+ pdev = platform_device_alloc("soc-camera-pdrv", i);
+ if (!pdev)
+ return -ENOMEM;
+
+ ret = platform_device_add_data(pdev, sdesc, sizeof(*sdesc));
+ if (ret < 0) {
+ platform_device_put(pdev);
+ return ret;
+ }
+
+ sasc->pdev = pdev;
+
+ return 0;
+}
+
+static struct soc_camera_device *soc_camera_add_pdev(struct soc_camera_async_client *sasc)
+{
+ struct platform_device *pdev = sasc->pdev;
+ int ret;
+
+ ret = platform_device_add(pdev);
+ if (ret < 0 || !pdev->dev.driver)
+ return NULL;
+
+ return platform_get_drvdata(pdev);
+}
+
+/* Locking: called with .host_lock held */
+static int soc_camera_probe_finish(struct soc_camera_device *icd)
+{
+ struct v4l2_subdev *sd = soc_camera_to_subdev(icd);
+ struct v4l2_mbus_framefmt mf;
+ int ret;
+
+ sd->grp_id = soc_camera_grp_id(icd);
+ v4l2_set_subdev_hostdata(sd, icd);
+
+ ret = v4l2_ctrl_add_handler(&icd->ctrl_handler, sd->ctrl_handler, NULL);
+ if (ret < 0)
+ return ret;
+
+ ret = soc_camera_add_device(icd);
+ if (ret < 0) {
+ dev_err(icd->pdev, "Couldn't activate the camera: %d\n", ret);
+ return ret;
+ }
+
+ /* At this point client .probe() should have run already */
+ ret = soc_camera_init_user_formats(icd);
+ if (ret < 0)
+ goto eusrfmt;
+
+ icd->field = V4L2_FIELD_ANY;
+
+ ret = soc_camera_video_start(icd);
+ if (ret < 0)
+ goto evidstart;
+
+ /* Try to improve our guess of a reasonable window format */
+ if (!v4l2_subdev_call(sd, video, g_mbus_fmt, &mf)) {
+ icd->user_width = mf.width;
+ icd->user_height = mf.height;
+ icd->colorspace = mf.colorspace;
+ icd->field = mf.field;
+ }
+ soc_camera_remove_device(icd);
+
+ return 0;
+
+evidstart:
+ soc_camera_free_user_formats(icd);
+eusrfmt:
+ soc_camera_remove_device(icd);
+
+ return ret;
+}
+
#ifdef CONFIG_I2C_BOARDINFO
-static int soc_camera_init_i2c(struct soc_camera_device *icd,
+static int soc_camera_i2c_init(struct soc_camera_device *icd,
struct soc_camera_desc *sdesc)
{
struct i2c_client *client;
- struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
+ struct soc_camera_host *ici;
struct soc_camera_host_desc *shd = &sdesc->host_desc;
- struct i2c_adapter *adap = i2c_get_adapter(shd->i2c_adapter_id);
+ struct i2c_adapter *adap;
struct v4l2_subdev *subdev;
char clk_name[V4L2_SUBDEV_NAME_SIZE];
int ret;

+ /* First find out how we link the main client */
+ if (icd->sasc) {
+ /* Async non-OF probing handled by the subdevice list */
+ return -EPROBE_DEFER;
+ }
+
+ ici = to_soc_camera_host(icd->parent);
+ adap = i2c_get_adapter(shd->i2c_adapter_id);
if (!adap) {
dev_err(icd->pdev, "Cannot get I2C adapter #%d. No driver?\n",
shd->i2c_adapter_id);
@@ -1242,42 +1389,202 @@ static int soc_camera_init_i2c(struct soc_camera_device *icd,
return 0;
ei2cnd:
v4l2_clk_unregister(icd->clk);
- icd->clk = NULL;
eclkreg:
+ icd->clk = NULL;
i2c_put_adapter(adap);
return ret;
}

-static void soc_camera_free_i2c(struct soc_camera_device *icd)
+static void soc_camera_i2c_free(struct soc_camera_device *icd)
{
struct i2c_client *client =
to_i2c_client(to_soc_camera_control(icd));
- struct i2c_adapter *adap = client->adapter;
+ struct i2c_adapter *adap;

icd->control = NULL;
+ if (icd->sasc)
+ return;
+
+ adap = client->adapter;
v4l2_device_unregister_subdev(i2c_get_clientdata(client));
i2c_unregister_device(client);
i2c_put_adapter(adap);
v4l2_clk_unregister(icd->clk);
icd->clk = NULL;
}
+
+/*
+ * V4L2 asynchronous notifier callbacks. They are all called under a v4l2-async
+ * internal global mutex, therefore cannot race against other asynchronous
+ * events. Until notifier->complete() (soc_camera_async_complete()) is called,
+ * the video device node is not registered and no V4L fops can occur. Unloading
+ * of the host driver also calls a v4l2-async function, so also there we're
+ * protected.
+ */
+static int soc_camera_async_bound(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *sd,
+ struct v4l2_async_subdev *asd)
+{
+ struct soc_camera_async_client *sasc = container_of(notifier,
+ struct soc_camera_async_client, notifier);
+ struct soc_camera_device *icd = platform_get_drvdata(sasc->pdev);
+
+ if (asd == sasc->sensor && !WARN_ON(icd->control)) {
+ struct i2c_client *client = v4l2_get_subdevdata(sd);
+
+ /*
+ * Only now we get subdevice-specific information like
+ * regulators, flags, callbacks, etc.
+ */
+ if (client) {
+ struct soc_camera_desc *sdesc = to_soc_camera_desc(icd);
+ struct soc_camera_subdev_desc *ssdd =
+ soc_camera_i2c_to_desc(client);
+ if (ssdd) {
+ memcpy(&sdesc->subdev_desc, ssdd,
+ sizeof(sdesc->subdev_desc));
+ if (ssdd->reset)
+ ssdd->reset(icd->pdev);
+ }
+
+ icd->control = &client->dev;
+ }
+ }
+
+ return 0;
+}
+
+static void soc_camera_async_unbind(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *sd,
+ struct v4l2_async_subdev *asd)
+{
+ struct soc_camera_async_client *sasc = container_of(notifier,
+ struct soc_camera_async_client, notifier);
+ struct soc_camera_device *icd = platform_get_drvdata(sasc->pdev);
+
+ if (icd->clk) {
+ v4l2_clk_unregister(icd->clk);
+ icd->clk = NULL;
+ }
+}
+
+static int soc_camera_async_complete(struct v4l2_async_notifier *notifier)
+{
+ struct soc_camera_async_client *sasc = container_of(notifier,
+ struct soc_camera_async_client, notifier);
+ struct soc_camera_device *icd = platform_get_drvdata(sasc->pdev);
+
+ if (to_soc_camera_control(icd)) {
+ struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
+ int ret;
+
+ mutex_lock(&list_lock);
+ ret = soc_camera_probe(ici, icd);
+ mutex_unlock(&list_lock);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int scan_async_group(struct soc_camera_host *ici,
+ struct v4l2_async_subdev **asd, int size)
+{
+ struct soc_camera_async_subdev *sasd;
+ struct soc_camera_async_client *sasc;
+ struct soc_camera_device *icd;
+ struct soc_camera_desc sdesc = {.host_desc.bus_id = ici->nr,};
+ char clk_name[V4L2_SUBDEV_NAME_SIZE];
+ int ret, i;
+
+ /* First look for a sensor */
+ for (i = 0; i < size; i++) {
+ sasd = container_of(asd[i], struct soc_camera_async_subdev, asd);
+ if (sasd->role == SOCAM_SUBDEV_DATA_SOURCE)
+ break;
+ }
+
+ if (i == size || asd[i]->bus_type != V4L2_ASYNC_BUS_I2C) {
+ /* All useless */
+ dev_err(ici->v4l2_dev.dev, "No I2C data source found!\n");
+ return -ENODEV;
+ }
+
+ /* Or shall this be managed by the soc-camera device? */
+ sasc = devm_kzalloc(ici->v4l2_dev.dev, sizeof(*sasc), GFP_KERNEL);
+ if (!sasc)
+ return -ENOMEM;
+
+ /* HACK: just need a != NULL */
+ sdesc.host_desc.board_info = ERR_PTR(-ENODATA);
+
+ ret = soc_camera_dyn_pdev(&sdesc, sasc);
+ if (ret < 0)
+ return ret;
+
+ sasc->sensor = &sasd->asd;
+
+ icd = soc_camera_add_pdev(sasc);
+ if (!icd) {
+ platform_device_put(sasc->pdev);
+ return -ENOMEM;
+ }
+
+ sasc->notifier.subdev = asd;
+ sasc->notifier.subdev_num = size;
+ sasc->notifier.bound = soc_camera_async_bound;
+ sasc->notifier.unbind = soc_camera_async_unbind;
+ sasc->notifier.complete = soc_camera_async_complete;
+
+ icd->sasc = sasc;
+ icd->parent = ici->v4l2_dev.dev;
+
+ snprintf(clk_name, sizeof(clk_name), "%d-%04x",
+ sasd->asd.match.i2c.adapter_id, sasd->asd.match.i2c.address);
+
+ icd->clk = v4l2_clk_register(&soc_camera_clk_ops, clk_name, "mclk", icd);
+ if (IS_ERR(icd->clk)) {
+ ret = PTR_ERR(icd->clk);
+ goto eclkreg;
+ }
+
+ ret = v4l2_async_notifier_register(&ici->v4l2_dev, &sasc->notifier);
+ if (!ret)
+ return 0;
+
+ v4l2_clk_unregister(icd->clk);
+eclkreg:
+ icd->clk = NULL;
+ platform_device_unregister(sasc->pdev);
+ dev_err(ici->v4l2_dev.dev, "group probe failed: %d\n", ret);
+
+ return ret;
+}
+
+static void scan_async_host(struct soc_camera_host *ici)
+{
+ struct v4l2_async_subdev **asd;
+ int j;
+
+ for (j = 0, asd = ici->asd; ici->asd_sizes[j]; j++) {
+ scan_async_group(ici, asd, ici->asd_sizes[j]);
+ asd += ici->asd_sizes[j];
+ }
+}
#else
-#define soc_camera_init_i2c(icd, sdesc) (-ENODEV)
-#define soc_camera_free_i2c(icd) do {} while (0)
+#define soc_camera_i2c_init(icd, sdesc) (-ENODEV)
+#define soc_camera_i2c_free(icd) do {} while (0)
+#define scan_async_host(ici) do {} while (0)
#endif

-static int soc_camera_video_start(struct soc_camera_device *icd);
-static int video_dev_create(struct soc_camera_device *icd);
/* Called during host-driver probe */
-static int soc_camera_probe(struct soc_camera_device *icd)
+static int soc_camera_probe(struct soc_camera_host *ici,
+ struct soc_camera_device *icd)
{
- struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
struct soc_camera_desc *sdesc = to_soc_camera_desc(icd);
struct soc_camera_host_desc *shd = &sdesc->host_desc;
- struct soc_camera_subdev_desc *ssdd = &sdesc->subdev_desc;
struct device *control = NULL;
- struct v4l2_subdev *sd;
- struct v4l2_mbus_framefmt mf;
int ret;

dev_info(icd->pdev, "Probing %s\n", dev_name(icd->pdev));
@@ -1293,10 +1600,6 @@ static int soc_camera_probe(struct soc_camera_device *icd)
if (ret < 0)
return ret;

- /* The camera could have been already on, try to reset */
- if (ssdd->reset)
- ssdd->reset(icd->pdev);
-
/* Must have icd->vdev before registering the device */
ret = video_dev_create(icd);
if (ret < 0)
@@ -1307,18 +1610,19 @@ static int soc_camera_probe(struct soc_camera_device *icd)
* itself is protected against concurrent open() calls, but we also have
* to protect our data also during client probing.
*/
- mutex_lock(&ici->host_lock);

/* Non-i2c cameras, e.g., soc_camera_platform, have no board_info */
if (shd->board_info) {
- ret = soc_camera_init_i2c(icd, sdesc);
- if (ret < 0)
+ ret = soc_camera_i2c_init(icd, sdesc);
+ if (ret < 0 && ret != -EPROBE_DEFER)
goto eadd;
} else if (!shd->add_device || !shd->del_device) {
ret = -EINVAL;
goto eadd;
} else {
+ mutex_lock(&ici->clk_lock);
ret = ici->ops->clock_start(ici);
+ mutex_unlock(&ici->clk_lock);
if (ret < 0)
goto eadd;

@@ -1342,57 +1646,33 @@ static int soc_camera_probe(struct soc_camera_device *icd)
}
}

- sd = soc_camera_to_subdev(icd);
- sd->grp_id = soc_camera_grp_id(icd);
- v4l2_set_subdev_hostdata(sd, icd);
-
- ret = v4l2_ctrl_add_handler(&icd->ctrl_handler, sd->ctrl_handler, NULL);
- if (ret < 0)
- goto ectrl;
-
- /* At this point client .probe() should have run already */
- ret = soc_camera_init_user_formats(icd);
- if (ret < 0)
- goto eiufmt;
-
- icd->field = V4L2_FIELD_ANY;
-
- ret = soc_camera_video_start(icd);
- if (ret < 0)
- goto evidstart;
-
- /* Try to improve our guess of a reasonable window format */
- if (!v4l2_subdev_call(sd, video, g_mbus_fmt, &mf)) {
- icd->user_width = mf.width;
- icd->user_height = mf.height;
- icd->colorspace = mf.colorspace;
- icd->field = mf.field;
- }
-
- if (!shd->board_info)
- ici->ops->clock_stop(ici);
-
+ mutex_lock(&ici->host_lock);
+ ret = soc_camera_probe_finish(icd);
mutex_unlock(&ici->host_lock);
+ if (ret < 0)
+ goto efinish;

return 0;

-evidstart:
- soc_camera_free_user_formats(icd);
-eiufmt:
-ectrl:
+efinish:
if (shd->board_info) {
- soc_camera_free_i2c(icd);
+ soc_camera_i2c_free(icd);
} else {
shd->del_device(icd);
module_put(control->driver->owner);
enodrv:
eadddev:
+ mutex_lock(&ici->clk_lock);
ici->ops->clock_stop(ici);
+ mutex_unlock(&ici->clk_lock);
}
eadd:
video_device_release(icd->vdev);
icd->vdev = NULL;
- mutex_unlock(&ici->host_lock);
+ if (icd->vdev) {
+ video_device_release(icd->vdev);
+ icd->vdev = NULL;
+ }
evdc:
v4l2_ctrl_handler_free(&icd->ctrl_handler);
return ret;
@@ -1400,15 +1680,15 @@ evdc:

/*
* This is called on device_unregister, which only means we have to disconnect
- * from the host, but not remove ourselves from the device list
+ * from the host, but not remove ourselves from the device list. With
+ * asynchronous client probing this can also be called without
+ * soc_camera_probe_finish() having run. Careful with clean up.
*/
static int soc_camera_remove(struct soc_camera_device *icd)
{
struct soc_camera_desc *sdesc = to_soc_camera_desc(icd);
struct video_device *vdev = icd->vdev;

- BUG_ON(!icd->parent);
-
v4l2_ctrl_handler_free(&icd->ctrl_handler);
if (vdev) {
video_unregister_device(vdev);
@@ -1416,15 +1696,27 @@ static int soc_camera_remove(struct soc_camera_device *icd)
}

if (sdesc->host_desc.board_info) {
- soc_camera_free_i2c(icd);
+ soc_camera_i2c_free(icd);
} else {
- struct device_driver *drv = to_soc_camera_control(icd)->driver;
+ struct device *dev = to_soc_camera_control(icd);
+ struct device_driver *drv = dev ? dev->driver : NULL;
if (drv) {
sdesc->host_desc.del_device(icd);
module_put(drv->owner);
}
}
- soc_camera_free_user_formats(icd);
+
+ if (icd->num_user_formats)
+ soc_camera_free_user_formats(icd);
+
+ if (icd->clk) {
+ /* For the synchronous case */
+ v4l2_clk_unregister(icd->clk);
+ icd->clk = NULL;
+ }
+
+ if (icd->sasc)
+ platform_device_unregister(icd->sasc->pdev);

return 0;
}
@@ -1535,7 +1827,18 @@ int soc_camera_host_register(struct soc_camera_host *ici)
mutex_unlock(&list_lock);

mutex_init(&ici->host_lock);
- scan_add_host(ici);
+ mutex_init(&ici->clk_lock);
+
+ if (ici->asd_sizes)
+ /*
+ * No OF, host with a list of subdevices. Don't try to mix
+ * modes by initialising some groups statically and some
+ * dynamically!
+ */
+ scan_async_host(ici);
+ else
+ /* Legacy: static platform devices from board data */
+ scan_add_host(ici);

return 0;

@@ -1548,13 +1851,30 @@ EXPORT_SYMBOL(soc_camera_host_register);
/* Unregister all clients! */
void soc_camera_host_unregister(struct soc_camera_host *ici)
{
- struct soc_camera_device *icd;
+ struct soc_camera_device *icd, *tmp;
+ struct soc_camera_async_client *sasc;
+ LIST_HEAD(notifiers);

mutex_lock(&list_lock);
-
list_del(&ici->list);
list_for_each_entry(icd, &devices, list)
- if (icd->iface == ici->nr && to_soc_camera_control(icd))
+ if (icd->iface == ici->nr && icd->sasc) {
+ /* as long as we hold the device, sasc won't be freed */
+ get_device(icd->pdev);
+ list_add(&icd->sasc->list, &notifiers);
+ }
+ mutex_unlock(&list_lock);
+
+ list_for_each_entry(sasc, &notifiers, list) {
+ /* Must call unlocked to avoid AB-BA dead-lock */
+ v4l2_async_notifier_unregister(&sasc->notifier);
+ put_device(&sasc->pdev->dev);
+ }
+
+ mutex_lock(&list_lock);
+
+ list_for_each_entry_safe(icd, tmp, &devices, list)
+ if (icd->iface == ici->nr)
soc_camera_remove(icd);

mutex_unlock(&list_lock);
@@ -1569,6 +1889,7 @@ static int soc_camera_device_register(struct soc_camera_device *icd)
struct soc_camera_device *ix;
int num = -1, i;

+ mutex_lock(&list_lock);
for (i = 0; i < 256 && num < 0; i++) {
num = i;
/* Check if this index is available on this interface */
@@ -1580,18 +1901,34 @@ static int soc_camera_device_register(struct soc_camera_device *icd)
}
}

- if (num < 0)
+ if (num < 0) {
/*
* ok, we have 256 cameras on this host...
* man, stay reasonable...
*/
+ mutex_unlock(&list_lock);
return -ENOMEM;
+ }

icd->devnum = num;
icd->use_count = 0;
icd->host_priv = NULL;

+ /*
+ * Dynamically allocated devices set the bit earlier, but it doesn't hurt setting
+ * it again
+ */
+ i = to_platform_device(icd->pdev)->id;
+ if (i < 0)
+ /* One static (legacy) soc-camera platform device */
+ i = 0;
+ if (i >= MAP_MAX_NUM) {
+ mutex_unlock(&list_lock);
+ return -EBUSY;
+ }
+ set_bit(i, device_map);
list_add_tail(&icd->list, &devices);
+ mutex_unlock(&list_lock);

return 0;
}
@@ -1691,6 +2028,12 @@ static int soc_camera_pdrv_probe(struct platform_device *pdev)
if (!icd)
return -ENOMEM;

+ /*
+ * In the asynchronous case ssdd->num_regulators == 0 yet, so, the below
+ * regulator allocation is a dummy. They will be really requested later
+ * in soc_camera_async_bind(). Also note, that in that case regulators
+ * are attached to the I2C device and not to the camera platform device.
+ */
ret = devm_regulator_bulk_get(&pdev->dev, ssdd->num_regulators,
ssdd->regulators);
if (ret < 0)
@@ -1715,11 +2058,25 @@ static int soc_camera_pdrv_probe(struct platform_device *pdev)
static int soc_camera_pdrv_remove(struct platform_device *pdev)
{
struct soc_camera_device *icd = platform_get_drvdata(pdev);
+ int i;

if (!icd)
return -EINVAL;

- list_del(&icd->list);
+ i = pdev->id;
+ if (i < 0)
+ i = 0;
+
+ /*
+ * In synchronous mode with static platform devices this is called in a
+ * loop from drivers/base/dd.c::driver_detach(), no parallel execution,
+ * no need to lock. In asynchronous case the caller -
+ * soc_camera_host_unregister() - already holds the lock
+ */
+ if (test_bit(i, device_map)) {
+ clear_bit(i, device_map);
+ list_del(&icd->list);
+ }

return 0;
}
diff --git a/include/media/soc_camera.h b/include/media/soc_camera.h
index f8c1ffe..2d3c939 100644
--- a/include/media/soc_camera.h
+++ b/include/media/soc_camera.h
@@ -19,11 +19,13 @@
#include <linux/videodev2.h>
#include <media/videobuf-core.h>
#include <media/videobuf2-core.h>
+#include <media/v4l2-async.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>

struct file;
struct soc_camera_desc;
+struct soc_camera_async_client;

struct soc_camera_device {
struct list_head list; /* list of all registered devices */
@@ -50,6 +52,9 @@ struct soc_camera_device {
int use_count;
struct file *streamer; /* stream owner */
struct v4l2_clk *clk;
+ /* Asynchronous subdevice management */
+ struct soc_camera_async_client *sasc;
+ /* video buffer queue */
union {
struct videobuf_queue vb_vidq;
struct vb2_queue vb2_vidq;
@@ -59,16 +64,30 @@ struct soc_camera_device {
/* Host supports programmable stride */
#define SOCAM_HOST_CAP_STRIDE (1 << 0)

+enum soc_camera_subdev_role {
+ SOCAM_SUBDEV_DATA_SOURCE = 1,
+ SOCAM_SUBDEV_DATA_SINK,
+ SOCAM_SUBDEV_DATA_PROCESSOR,
+};
+
+struct soc_camera_async_subdev {
+ struct v4l2_async_subdev asd;
+ enum soc_camera_subdev_role role;
+};
+
struct soc_camera_host {
struct v4l2_device v4l2_dev;
struct list_head list;
- struct mutex host_lock; /* Protect pipeline modifications */
+ struct mutex host_lock; /* Main synchronisation lock */
+ struct mutex clk_lock; /* Protect pipeline modifications */
unsigned char nr; /* Host number */
u32 capabilities;
struct soc_camera_device *icd; /* Currently attached client */
void *priv;
const char *drv_name;
struct soc_camera_host_ops *ops;
+ struct v4l2_async_subdev **asd; /* Flat array, arranged in groups */
+ int *asd_sizes; /* 0-terminated array of asd group sizes */
};

struct soc_camera_host_ops {
@@ -161,6 +180,7 @@ struct soc_camera_host_desc {
};

/*
+ * Platform data for "soc-camera-pdrv"
* This MUST be kept binary-identical to struct soc_camera_link below, until
* it is completely replaced by this one, after which we can split it into its
* two components.
@@ -326,6 +346,7 @@ static inline void soc_camera_limit_side(int *start, int *length,
unsigned long soc_camera_apply_board_flags(struct soc_camera_subdev_desc *ssdd,
const struct v4l2_mbus_config *cfg);

+int soc_camera_power_init(struct device *dev, struct soc_camera_subdev_desc *ssdd);
int soc_camera_power_on(struct device *dev, struct soc_camera_subdev_desc *ssdd,
struct v4l2_clk *clk);
int soc_camera_power_off(struct device *dev, struct soc_camera_subdev_desc *ssdd,
--
1.7.2.5