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Diffstat (limited to 'drivers/staging/greybus/gb-camera.h')
| -rw-r--r-- | drivers/staging/greybus/gb-camera.h | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/drivers/staging/greybus/gb-camera.h b/drivers/staging/greybus/gb-camera.h new file mode 100644 index 000000000000..d45dabc5b367 --- /dev/null +++ b/drivers/staging/greybus/gb-camera.h @@ -0,0 +1,127 @@ +/* + * Greybus Camera protocol driver. + * + * Copyright 2015 Google Inc. + * + * Released under the GPLv2 only. + */ +#ifndef __GB_CAMERA_H +#define __GB_CAMERA_H + +#include <linux/v4l2-mediabus.h> + +/* Input flags need to be set from the caller */ +#define GB_CAMERA_IN_FLAG_TEST (1 << 0) +/* Output flags returned */ +#define GB_CAMERA_OUT_FLAG_ADJUSTED (1 << 0) + +/** + * struct gb_camera_stream - Represents greybus camera stream. + * @width: Stream width in pixels. + * @height: Stream height in pixels. + * @pixel_code: Media bus pixel code. + * @vc: MIPI CSI virtual channel. + * @dt: MIPI CSI data types. Most formats use a single data type, in which case + * the second element will be ignored. + * @max_size: Maximum size of a frame in bytes. The camera module guarantees + * that all data between the Frame Start and Frame End packet for + * the associated virtual channel and data type(s) will not exceed + * this size. + */ +struct gb_camera_stream { + unsigned int width; + unsigned int height; + enum v4l2_mbus_pixelcode pixel_code; + unsigned int vc; + unsigned int dt[2]; + unsigned int max_size; +}; + +/** + * struct gb_camera_csi_params - CSI configuration parameters + * @num_lanes: number of CSI data lanes + * @clk_freq: CSI clock frequency in Hz + */ +struct gb_camera_csi_params { + unsigned int num_lanes; + unsigned int clk_freq; +}; + +/** + * struct gb_camera_ops - Greybus camera operations, used by the Greybus camera + * driver to expose operations to the host camera driver. + * @capabilities: Retrieve camera capabilities and store them in the buffer + * 'buf' capabilities. The buffer maximum size is specified by + * the caller in the 'size' parameter, and the effective + * capabilities size is returned from the function. If the buffer + * size is too small to hold the capabilities an error is + * returned and the buffer is left untouched. + * + * @configure_streams: Negotiate configuration and prepare the module for video + * capture. The caller specifies the number of streams it + * requests in the 'nstreams' argument and the associated + * streams configurations in the 'streams' argument. The + * GB_CAMERA_IN_FLAG_TEST 'flag' can be set to test a + * configuration without applying it, otherwise the + * configuration is applied by the module. The module can + * decide to modify the requested configuration, including + * using a different number of streams. In that case the + * modified configuration won't be applied, the + * GB_CAMERA_OUT_FLAG_ADJUSTED 'flag' will be set upon + * return, and the modified configuration and number of + * streams stored in 'streams' and 'array'. The module + * returns its CSI-2 bus parameters in the 'csi_params' + * structure in all cases. + * + * @capture: Submit a capture request. The supplied 'request_id' must be unique + * and higher than the IDs of all the previously submitted requests. + * The 'streams' argument specifies which streams are affected by the + * request in the form of a bitmask, with bits corresponding to the + * configured streams indexes. If the request contains settings, the + * 'settings' argument points to the settings buffer and its size is + * specified by the 'settings_size' argument. Otherwise the 'settings' + * argument should be set to NULL and 'settings_size' to 0. + * + * @flush: Flush the capture requests queue. Return the ID of the last request + * that will processed by the device before it stops transmitting video + * frames. All queued capture requests with IDs higher than the returned + * ID will be dropped without being processed. + */ +struct gb_camera_ops { + ssize_t (*capabilities)(void *priv, char *buf, size_t len); + int (*configure_streams)(void *priv, unsigned int *nstreams, + unsigned int *flags, struct gb_camera_stream *streams, + struct gb_camera_csi_params *csi_params); + int (*capture)(void *priv, u32 request_id, + unsigned int streams, unsigned int num_frames, + size_t settings_size, const void *settings); + int (*flush)(void *priv, u32 *request_id); +}; + +/** + * struct gb_camera_module - Represents greybus camera module. + * @priv: Module private data, passed to all camera operations. + * @ops: Greybus camera operation callbacks. + * @interface_id: Interface id of the module. + * @refcount: Reference counting object. + * @release: Module release function. + * @list: List entry in the camera modules list. + */ +struct gb_camera_module { + void *priv; + const struct gb_camera_ops *ops; + + unsigned int interface_id; + struct kref refcount; + void (*release)(struct kref *kref); + struct list_head list; /* Global list */ +}; + +#define gb_camera_call(f, op, args...) \ + (!(f) ? -ENODEV : (((f)->ops->op) ? \ + (f)->ops->op((f)->priv, ##args) : -ENOIOCTLCMD)) + +int gb_camera_register(struct gb_camera_module *module); +int gb_camera_unregister(struct gb_camera_module *module); + +#endif /* __GB_CAMERA_H */ |