From 7b43a6f3f517109c2912d82f7f666a84420689bc Mon Sep 17 00:00:00 2001 From: Sylwester Nawrocki Date: Wed, 12 Dec 2012 08:16:05 -0300 Subject: [PATCH] [media] s5p-fimc: Change platform subdevs registration method 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 Signed-off-by: Kyungmin Park Signed-off-by: Mauro Carvalho Chehab --- .../media/platform/s5p-fimc/fimc-mdevice.c | 205 ++++++++++-------- 1 file changed, 109 insertions(+), 96 deletions(-) diff --git a/drivers/media/platform/s5p-fimc/fimc-mdevice.c b/drivers/media/platform/s5p-fimc/fimc-mdevice.c index 52e1aa3c8982..2b0587204868 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, + * Copyright (C) 2011 - 2012 Samsung Electronics Co., Ltd. + * Sylwester Nawrocki * * 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_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) + 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 register_fimc_entity(struct fimc_md *fmd, struct fimc_dev *fimc) +{ + struct v4l2_subdev *sd; + int ret; + + if (WARN_ON(fimc->id >= FIMC_MAX_DEVS || fmd->fimc[fimc->id])) + return -EBUSY; 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, sd); - if (ret) { + 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); - return ret; } - - fmd->fimc[fimc->id] = fimc; - return 0; + return ret; } -static int fimc_lite_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 fimc_lite *fimc = dev_get_drvdata(dev); - struct fimc_md *fmd = p; - int ret; - - if (fimc == NULL || fimc->index >= FIMC_LITE_MAX_DEVS) - return 0; - - fimc->subdev.grp_id = GRP_ID_FLITE; - v4l2_set_subdev_hostdata(&fimc->subdev, (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; - } - - fmd->fimc_lite[fimc->index] = fimc; - return 0; -} - -static int csis_register_callback(struct device *dev, void *p) -{ - 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) - return 0; - v4l2_info(sd, "csis%d sd: %s\n", pdev->id, sd->name); + 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; - 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; + struct device *dev = &pdev->dev; + int ret = -EPROBE_DEFER; + void *drvdata; - 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; - } + /* Lock to ensure dev->driver won't change. */ + device_lock(dev); - ret = driver_for_each_device(driver, NULL, fmd, - fimc_register_callback); - if (ret) - return ret; + if (!dev->driver || !try_module_get(dev->driver->owner)) + goto dev_unlock; - 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; + 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"); } /** @@ -939,7 +951,8 @@ 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;