| 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
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| 2 | /* |
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| 3 | * v4l2-spi - SPI helpers for Video4Linux2 |
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| 4 | */ |
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| 5 | |
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| 6 | #include <linux/module.h> |
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| 7 | #include <linux/spi/spi.h> |
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| 8 | #include <media/v4l2-common.h> |
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| 9 | #include <media/v4l2-device.h> |
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| 10 | |
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| 11 | void v4l2_spi_subdev_unregister(struct v4l2_subdev *sd) |
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| 12 | { |
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| 13 | struct spi_device *spi = v4l2_get_subdevdata(sd); |
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| 14 | |
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| 15 | if (spi && !spi->dev.of_node && !spi->dev.fwnode) |
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| 16 | spi_unregister_device(spi); |
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| 17 | } |
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| 18 | |
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| 19 | void v4l2_spi_subdev_init(struct v4l2_subdev *sd, struct spi_device *spi, |
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| 20 | const struct v4l2_subdev_ops *ops) |
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| 21 | { |
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| 22 | v4l2_subdev_init(sd, ops); |
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| 23 | sd->flags |= V4L2_SUBDEV_FL_IS_SPI; |
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| 24 | /* the owner is the same as the spi_device's driver owner */ |
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| 25 | sd->owner = spi->dev.driver->owner; |
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| 26 | sd->dev = &spi->dev; |
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| 27 | /* spi_device and v4l2_subdev point to one another */ |
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| 28 | v4l2_set_subdevdata(sd, p: spi); |
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| 29 | spi_set_drvdata(spi, data: sd); |
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| 30 | /* initialize name */ |
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| 31 | snprintf(buf: sd->name, size: sizeof(sd->name), fmt: "%s %s" , |
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| 32 | spi->dev.driver->name, dev_name(dev: &spi->dev)); |
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| 33 | } |
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| 34 | EXPORT_SYMBOL_GPL(v4l2_spi_subdev_init); |
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| 35 | |
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| 36 | struct v4l2_subdev *v4l2_spi_new_subdev(struct v4l2_device *v4l2_dev, |
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| 37 | struct spi_controller *ctlr, |
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| 38 | struct spi_board_info *info) |
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| 39 | { |
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| 40 | struct v4l2_subdev *sd = NULL; |
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| 41 | struct spi_device *spi = NULL; |
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| 42 | |
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| 43 | if (!v4l2_dev) |
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| 44 | return NULL; |
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| 45 | if (info->modalias[0]) |
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| 46 | request_module(info->modalias); |
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| 47 | |
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| 48 | spi = spi_new_device(ctlr, info); |
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| 49 | |
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| 50 | if (!spi || !spi->dev.driver) |
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| 51 | goto error; |
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| 52 | |
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| 53 | if (!try_module_get(module: spi->dev.driver->owner)) |
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| 54 | goto error; |
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| 55 | |
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| 56 | sd = spi_get_drvdata(spi); |
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| 57 | |
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| 58 | /* |
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| 59 | * Register with the v4l2_device which increases the module's |
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| 60 | * use count as well. |
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| 61 | */ |
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| 62 | if (v4l2_device_register_subdev(v4l2_dev, sd)) |
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| 63 | sd = NULL; |
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| 64 | |
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| 65 | /* Decrease the module use count to match the first try_module_get. */ |
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| 66 | module_put(module: spi->dev.driver->owner); |
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| 67 | |
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| 68 | error: |
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| 69 | /* |
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| 70 | * If we have a client but no subdev, then something went wrong and |
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| 71 | * we must unregister the client. |
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| 72 | */ |
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| 73 | if (!sd) |
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| 74 | spi_unregister_device(spi); |
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| 75 | |
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| 76 | return sd; |
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| 77 | } |
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| 78 | EXPORT_SYMBOL_GPL(v4l2_spi_new_subdev); |
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| 79 | |
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