1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Greybus Camera protocol driver. 4 * 5 * Copyright 2015 Google Inc. 6 */ 7 #ifndef __GB_CAMERA_H 8 #define __GB_CAMERA_H 9 10 #include <linux/v4l2-mediabus.h> 11 12 /* Input flags need to be set from the caller */ 13 #define GB_CAMERA_IN_FLAG_TEST (1 << 0) 14 /* Output flags returned */ 15 #define GB_CAMERA_OUT_FLAG_ADJUSTED (1 << 0) 16 17 /** 18 * struct gb_camera_stream - Represents greybus camera stream. 19 * @width: Stream width in pixels. 20 * @height: Stream height in pixels. 21 * @pixel_code: Media bus pixel code. 22 * @vc: MIPI CSI virtual channel. 23 * @dt: MIPI CSI data types. Most formats use a single data type, in which case 24 * the second element will be ignored. 25 * @max_size: Maximum size of a frame in bytes. The camera module guarantees 26 * that all data between the Frame Start and Frame End packet for 27 * the associated virtual channel and data type(s) will not exceed 28 * this size. 29 */ 30 struct gb_camera_stream { 31 unsigned int width; 32 unsigned int height; 33 enum v4l2_mbus_pixelcode pixel_code; 34 unsigned int vc; 35 unsigned int dt[2]; 36 unsigned int max_size; 37 }; 38 39 /** 40 * struct gb_camera_csi_params - CSI configuration parameters 41 * @num_lanes: number of CSI data lanes 42 * @clk_freq: CSI clock frequency in Hz 43 */ 44 struct gb_camera_csi_params { 45 unsigned int num_lanes; 46 unsigned int clk_freq; 47 }; 48 49 /** 50 * struct gb_camera_ops - Greybus camera operations, used by the Greybus camera 51 * driver to expose operations to the host camera driver. 52 * @capabilities: Retrieve camera capabilities and store them in the buffer 53 * 'buf' capabilities. The buffer maximum size is specified by 54 * the caller in the 'size' parameter, and the effective 55 * capabilities size is returned from the function. If the buffer 56 * size is too small to hold the capabilities an error is 57 * returned and the buffer is left untouched. 58 * 59 * @configure_streams: Negotiate configuration and prepare the module for video 60 * capture. The caller specifies the number of streams it 61 * requests in the 'nstreams' argument and the associated 62 * streams configurations in the 'streams' argument. The 63 * GB_CAMERA_IN_FLAG_TEST 'flag' can be set to test a 64 * configuration without applying it, otherwise the 65 * configuration is applied by the module. The module can 66 * decide to modify the requested configuration, including 67 * using a different number of streams. In that case the 68 * modified configuration won't be applied, the 69 * GB_CAMERA_OUT_FLAG_ADJUSTED 'flag' will be set upon 70 * return, and the modified configuration and number of 71 * streams stored in 'streams' and 'array'. The module 72 * returns its CSI-2 bus parameters in the 'csi_params' 73 * structure in all cases. 74 * 75 * @capture: Submit a capture request. The supplied 'request_id' must be unique 76 * and higher than the IDs of all the previously submitted requests. 77 * The 'streams' argument specifies which streams are affected by the 78 * request in the form of a bitmask, with bits corresponding to the 79 * configured streams indexes. If the request contains settings, the 80 * 'settings' argument points to the settings buffer and its size is 81 * specified by the 'settings_size' argument. Otherwise the 'settings' 82 * argument should be set to NULL and 'settings_size' to 0. 83 * 84 * @flush: Flush the capture requests queue. Return the ID of the last request 85 * that will processed by the device before it stops transmitting video 86 * frames. All queued capture requests with IDs higher than the returned 87 * ID will be dropped without being processed. 88 */ 89 struct gb_camera_ops { 90 ssize_t (*capabilities)(void *priv, char *buf, size_t len); 91 int (*configure_streams)(void *priv, unsigned int *nstreams, 92 unsigned int *flags, struct gb_camera_stream *streams, 93 struct gb_camera_csi_params *csi_params); 94 int (*capture)(void *priv, u32 request_id, 95 unsigned int streams, unsigned int num_frames, 96 size_t settings_size, const void *settings); 97 int (*flush)(void *priv, u32 *request_id); 98 }; 99 100 /** 101 * struct gb_camera_module - Represents greybus camera module. 102 * @priv: Module private data, passed to all camera operations. 103 * @ops: Greybus camera operation callbacks. 104 * @interface_id: Interface id of the module. 105 * @refcount: Reference counting object. 106 * @release: Module release function. 107 * @list: List entry in the camera modules list. 108 */ 109 struct gb_camera_module { 110 void *priv; 111 const struct gb_camera_ops *ops; 112 113 unsigned int interface_id; 114 struct kref refcount; 115 void (*release)(struct kref *kref); 116 struct list_head list; /* Global list */ 117 }; 118 119 #define gb_camera_call(f, op, args...) \ 120 (!(f) ? -ENODEV : (((f)->ops->op) ? \ 121 (f)->ops->op((f)->priv, ##args) : -ENOIOCTLCMD)) 122 123 int gb_camera_register(struct gb_camera_module *module); 124 int gb_camera_unregister(struct gb_camera_module *module); 125 126 #endif /* __GB_CAMERA_H */ 127