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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * v4l2-spi - SPI helpers for Video4Linux24 */5 6#include <linux/module.h>7#include <linux/spi/spi.h>8#include <media/v4l2-common.h>9#include <media/v4l2-device.h>10 11void v4l2_spi_subdev_unregister(struct v4l2_subdev *sd)12{13 struct spi_device *spi = v4l2_get_subdevdata(sd);14 15 if (spi && !spi->dev.of_node && !spi->dev.fwnode)16 spi_unregister_device(spi);17}18 19void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi,20 const struct v4l2_subdev_ops *ops)21{22 v4l2_subdev_init(sd, ops);23 sd->flags |= V4L2_SUBDEV_FL_IS_SPI;24 /* the owner is the same as the spi_device's driver owner */25 sd->owner = spi->dev.driver->owner;26 sd->dev = &spi->dev;27 /* spi_device and v4l2_subdev point to one another */28 v4l2_set_subdevdata(sd, spi);29 spi_set_drvdata(spi, sd);30 /* initialize name */31 snprintf(sd->name, sizeof(sd->name), "%s %s",32 spi->dev.driver->name, dev_name(&spi->dev));33}34EXPORT_SYMBOL_GPL(v4l2_spi_subdev_init);35 36struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev,37 struct spi_controller *ctlr,38 struct spi_board_info *info)39{40 struct v4l2_subdev *sd = NULL;41 struct spi_device *spi = NULL;42 43 if (!v4l2_dev)44 return NULL;45 if (info->modalias[0])46 request_module(info->modalias);47 48 spi = spi_new_device(ctlr, info);49 50 if (!spi || !spi->dev.driver)51 goto error;52 53 if (!try_module_get(spi->dev.driver->owner))54 goto error;55 56 sd = spi_get_drvdata(spi);57 58 /*59 * Register with the v4l2_device which increases the module's60 * use count as well.61 */62 if (__v4l2_device_register_subdev(v4l2_dev, sd, sd->owner))63 sd = NULL;64 65 /* Decrease the module use count to match the first try_module_get. */66 module_put(spi->dev.driver->owner);67 68error:69 /*70 * If we have a client but no subdev, then something went wrong and71 * we must unregister the client.72 */73 if (!sd)74 spi_unregister_device(spi);75 76 return sd;77}78EXPORT_SYMBOL_GPL(v4l2_spi_new_subdev);79