[PATCH RFC v3 06/14] s5p-fimc: Change platform subdevs registration method
Sylwester Nawrocki
s.nawrocki at samsung.com
Thu Jan 24 06:31:21 EST 2013
The previous method of registering platform entities into the main
driver using driver_find() and then iterating over devices bound to
a driver was racy and is being removed here. Nothing was preventing
module from unloading during a call to try_module_get(driver->owner).
Instead, we look up a device first and then check for its driver while
holding device lock.
The platform sub-devices are looked up and registered to the top
level driver. When any sub-device is not yet initialized and ready
the main driver's probe() will be deferred.
Signed-off-by: Sylwester Nawrocki <s.nawrocki at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
---
drivers/media/platform/s5p-fimc/fimc-mdevice.c | 203 +++++++++++++-----------
1 file changed, 108 insertions(+), 95 deletions(-)
diff --git a/drivers/media/platform/s5p-fimc/fimc-mdevice.c b/drivers/media/platform/s5p-fimc/fimc-mdevice.c
index 501ac48..abf6000 100644
--- a/drivers/media/platform/s5p-fimc/fimc-mdevice.c
+++ b/drivers/media/platform/s5p-fimc/fimc-mdevice.c
@@ -1,8 +1,8 @@
/*
* S5P/EXYNOS4 SoC series camera host interface media device driver
*
- * Copyright (C) 2011 Samsung Electronics Co., Ltd.
- * Contact: Sylwester Nawrocki, <s.nawrocki at samsung.com>
+ * Copyright (C) 2011 - 2012 Samsung Electronics Co., Ltd.
+ * Sylwester Nawrocki <s.nawrocki at samsung.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
@@ -312,138 +312,149 @@ static int fimc_md_register_sensor_entities(struct fimc_md *fmd)
}
/*
- * MIPI CSIS and FIMC platform devices registration.
+ * MIPI-CSIS, FIMC and FIMC-LITE platform devices registration.
*/
-static int fimc_register_callback(struct device *dev, void *p)
+
+static int register_fimc_lite_entity(struct fimc_md *fmd,
+ struct fimc_lite *fimc_lite)
{
- struct fimc_dev *fimc = dev_get_drvdata(dev);
struct v4l2_subdev *sd;
- struct fimc_md *fmd = p;
int ret;
- if (fimc == NULL || fimc->id >= FIMC_MAX_DEVS)
- return 0;
+ if (WARN_ON(fimc_lite->index >= FIMC_LITE_MAX_DEVS ||
+ fmd->fimc_lite[fimc_lite->index]))
+ return -EBUSY;
- sd = &fimc->vid_cap.subdev;
- sd->grp_id = GRP_ID_FIMC;
+ sd = &fimc_lite->subdev;
+ sd->grp_id = GRP_ID_FLITE;
v4l2_set_subdev_hostdata(sd, (void *)&fimc_pipeline_ops);
ret = v4l2_device_register_subdev(&fmd->v4l2_dev, sd);
- if (ret) {
- v4l2_err(&fmd->v4l2_dev, "Failed to register FIMC.%d (%d)\n",
- fimc->id, ret);
- return ret;
- }
-
- fmd->fimc[fimc->id] = fimc;
- return 0;
+ if (!ret)
+ fmd->fimc_lite[fimc_lite->index] = fimc_lite;
+ else
+ v4l2_err(&fmd->v4l2_dev, "Failed to register FIMC.LITE%d\n",
+ fimc_lite->index);
+ return ret;
}
-static int fimc_lite_register_callback(struct device *dev, void *p)
+static int register_fimc_entity(struct fimc_md *fmd, struct fimc_dev *fimc)
{
- struct fimc_lite *fimc = dev_get_drvdata(dev);
- struct fimc_md *fmd = p;
+ struct v4l2_subdev *sd;
int ret;
- if (fimc == NULL || fimc->index >= FIMC_LITE_MAX_DEVS)
- return 0;
+ if (WARN_ON(fimc->id >= FIMC_MAX_DEVS || fmd->fimc[fimc->id]))
+ return -EBUSY;
- fimc->subdev.grp_id = GRP_ID_FLITE;
- v4l2_set_subdev_hostdata(&fimc->subdev, (void *)&fimc_pipeline_ops);
+ sd = &fimc->vid_cap.subdev;
+ sd->grp_id = GRP_ID_FIMC;
+ v4l2_set_subdev_hostdata(sd, (void *)&fimc_pipeline_ops);
- ret = v4l2_device_register_subdev(&fmd->v4l2_dev, &fimc->subdev);
- if (ret) {
- v4l2_err(&fmd->v4l2_dev,
- "Failed to register FIMC-LITE.%d (%d)\n",
- fimc->index, ret);
- return ret;
+ ret = v4l2_device_register_subdev(&fmd->v4l2_dev, sd);
+ if (!ret) {
+ fmd->fimc[fimc->id] = fimc;
+ fimc->vid_cap.user_subdev_api = fmd->user_subdev_api;
+ } else {
+ v4l2_err(&fmd->v4l2_dev, "Failed to register FIMC.%d (%d)\n",
+ fimc->id, ret);
}
-
- fmd->fimc_lite[fimc->index] = fimc;
- return 0;
+ return ret;
}
-static int csis_register_callback(struct device *dev, void *p)
+static int register_csis_entity(struct fimc_md *fmd,
+ struct platform_device *pdev,
+ struct v4l2_subdev *sd)
{
- struct v4l2_subdev *sd = dev_get_drvdata(dev);
- struct platform_device *pdev;
- struct fimc_md *fmd = p;
+ struct device_node *node = pdev->dev.of_node;
int id, ret;
- if (!sd)
- return 0;
- pdev = v4l2_get_subdevdata(sd);
- if (!pdev || pdev->id < 0 || pdev->id >= CSIS_MAX_ENTITIES)
+ id = node ? of_alias_get_id(node, "csis") : max(0, pdev->id);
+
+ if (WARN_ON(id >= CSIS_MAX_ENTITIES || fmd->csis[id].sd))
+ return -EBUSY;
+
+ if (WARN_ON(id >= CSIS_MAX_ENTITIES))
return 0;
- v4l2_info(sd, "csis%d sd: %s\n", pdev->id, sd->name);
- id = pdev->id < 0 ? 0 : pdev->id;
sd->grp_id = GRP_ID_CSIS;
-
ret = v4l2_device_register_subdev(&fmd->v4l2_dev, sd);
if (!ret)
fmd->csis[id].sd = sd;
else
v4l2_err(&fmd->v4l2_dev,
- "Failed to register CSIS subdevice: %d\n", ret);
+ "Failed to register MIPI-CSIS.%d (%d)\n", id, ret);
return ret;
}
-/**
- * fimc_md_register_platform_entities - register FIMC and CSIS media entities
- */
-static int fimc_md_register_platform_entities(struct fimc_md *fmd)
+static int fimc_md_register_platform_entity(struct fimc_md *fmd,
+ struct platform_device *pdev,
+ int plat_entity)
{
- struct s5p_platform_fimc *pdata = fmd->pdev->dev.platform_data;
- struct device_driver *driver;
- int ret, i;
-
- driver = driver_find(FIMC_MODULE_NAME, &platform_bus_type);
- if (!driver) {
- v4l2_warn(&fmd->v4l2_dev,
- "%s driver not found, deffering probe\n",
- FIMC_MODULE_NAME);
- return -EPROBE_DEFER;
- }
-
- ret = driver_for_each_device(driver, NULL, fmd,
- fimc_register_callback);
- if (ret)
- return ret;
-
- driver = driver_find(FIMC_LITE_DRV_NAME, &platform_bus_type);
- if (driver && try_module_get(driver->owner)) {
- ret = driver_for_each_device(driver, NULL, fmd,
- fimc_lite_register_callback);
- if (ret)
- return ret;
- module_put(driver->owner);
- }
- /*
- * Check if there is any sensor on the MIPI-CSI2 bus and
- * if not skip the s5p-csis module loading.
- */
- if (pdata == NULL)
- return 0;
- for (i = 0; i < pdata->num_clients; i++) {
- if (pdata->isp_info[i].bus_type == FIMC_MIPI_CSI2) {
- ret = 1;
+ struct device *dev = &pdev->dev;
+ int ret = -EPROBE_DEFER;
+ void *drvdata;
+
+ /* Lock to ensure dev->driver won't change. */
+ device_lock(dev);
+
+ if (!dev->driver || !try_module_get(dev->driver->owner))
+ goto dev_unlock;
+
+ drvdata = dev_get_drvdata(dev);
+ /* Some subdev didn't probe succesfully id drvdata is NULL */
+ if (drvdata) {
+ switch (plat_entity) {
+ case IDX_FIMC:
+ ret = register_fimc_entity(fmd, drvdata);
+ break;
+ case IDX_FLITE:
+ ret = register_fimc_lite_entity(fmd, drvdata);
break;
+ case IDX_CSIS:
+ ret = register_csis_entity(fmd, pdev, drvdata);
+ break;
+ default:
+ ret = -ENODEV;
}
}
- if (!ret)
- return 0;
- driver = driver_find(CSIS_DRIVER_NAME, &platform_bus_type);
- if (!driver || !try_module_get(driver->owner)) {
- v4l2_warn(&fmd->v4l2_dev,
- "%s driver not found, deffering probe\n",
- CSIS_DRIVER_NAME);
- return -EPROBE_DEFER;
+ module_put(dev->driver->owner);
+dev_unlock:
+ device_unlock(dev);
+ if (ret == -EPROBE_DEFER)
+ dev_info(&fmd->pdev->dev, "deferring %s device registration\n",
+ dev_name(dev));
+ else if (ret < 0)
+ dev_err(&fmd->pdev->dev, "%s device registration failed (%d)\n",
+ dev_name(dev), ret);
+ return ret;
+}
+
+static int fimc_md_pdev_match(struct device *dev, void *data)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ int plat_entity = -1;
+ int ret;
+ char *p;
+
+ if (!get_device(dev))
+ return -ENODEV;
+
+ if (!strcmp(pdev->name, CSIS_DRIVER_NAME)) {
+ plat_entity = IDX_CSIS;
+ } else if (!strcmp(pdev->name, FIMC_LITE_DRV_NAME)) {
+ plat_entity = IDX_FLITE;
+ } else {
+ p = strstr(pdev->name, "fimc");
+ if (p && *(p + 4) == 0)
+ plat_entity = IDX_FIMC;
}
- return driver_for_each_device(driver, NULL, fmd,
- csis_register_callback);
+ if (plat_entity >= 0)
+ ret = fimc_md_register_platform_entity(data, pdev,
+ plat_entity);
+ put_device(dev);
+ return 0;
}
static void fimc_md_unregister_entities(struct fimc_md *fmd)
@@ -477,6 +488,7 @@ static void fimc_md_unregister_entities(struct fimc_md *fmd)
fimc_md_unregister_sensor(fmd->sensor[i].subdev);
fmd->sensor[i].subdev = NULL;
}
+ v4l2_info(&fmd->v4l2_dev, "Unregistered all entities\n");
}
/**
@@ -941,7 +953,8 @@ static int fimc_md_probe(struct platform_device *pdev)
/* Protect the media graph while we're registering entities */
mutex_lock(&fmd->media_dev.graph_mutex);
- ret = fimc_md_register_platform_entities(fmd);
+ ret = bus_for_each_dev(&platform_bus_type, NULL, fmd,
+ fimc_md_pdev_match);
if (ret)
goto err_unlock;
--
1.7.9.5
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