libsigrok驱动开发结构解析

static struct sr_dev_driver demo_driver_info = {
    .name = "demo",
    .longname = "Demo driver and pattern generator",
    .api_version = 1,
    .init = std_init,
    .cleanup = std_cleanup,
    .scan = scan,
    .dev_list = std_dev_list,
    .dev_clear = dev_clear,
    .config_get = config_get,
    .config_set = config_set,
    .config_list = config_list,
    .dev_open = std_dummy_dev_open,
    .dev_close = std_dummy_dev_close,
    .dev_acquisition_start = dev_acquisition_start,
    .dev_acquisition_stop = dev_acquisition_stop,
    .context = NULL,
};

/** Called when driver is loaded, e.g. program startup. */
int (*init) (struct sr_dev_driver *driver, struct sr_context *sr_ctx);
/** Called before driver is unloaded.
 *  Driver must free all resources held by it. */
int (*cleanup) (const struct sr_dev_driver *driver);

/** Scan for devices. Driver should do all initialisation required.
 *  Can be called several times, e.g. with different port options.
 *  @retval NULL Error or no devices found.
 *  @retval other GSList of a struct sr_dev_inst for each device.
 *                Must be freed by caller!
 */
GSList *(*scan) (struct sr_dev_driver *driver, GSList *options);
/** Get list of device instances the driver knows about.
 *  @returns NULL or GSList of a struct sr_dev_inst for each device.
 *           Must not be freed by caller!
 */
GSList *(*dev_list) (const struct sr_dev_driver *driver);
/** Clear list of devices the driver knows about. */
int (*dev_clear) (const struct sr_dev_driver *driver);

/** Query value of a configuration key in driver or given device instance.
 *  @see sr_config_get().
 */
int (*config_get) (uint32_t key, GVariant **data,
        const struct sr_dev_inst *sdi,
        const struct sr_channel_group *cg);
/** Set value of a configuration key in driver or a given device instance.
 *  @see sr_config_set(). */
int (*config_set) (uint32_t key, GVariant *data,
        const struct sr_dev_inst *sdi,
        const struct sr_channel_group *cg);
/** List all possible values for a configuration key in a device instance.
 *  @see sr_config_list().
 */
int (*config_list) (uint32_t key, GVariant **data,
        const struct sr_dev_inst *sdi,
        const struct sr_channel_group *cg);

/** Open device */
int (*dev_open) (struct sr_dev_inst *sdi);
/** Close device */
int (*dev_close) (struct sr_dev_inst *sdi);

/** Begin data acquisition on the specified device. */
int (*dev_acquisition_start) (const struct sr_dev_inst *sdi);
/** End data acquisition on the specified device. */
int (*dev_acquisition_stop) (struct sr_dev_inst *sdi);

/**
 * Add an event source for a file descriptor.
 *
 * @param session The session to use. Must not be NULL.
 * @param fd The file descriptor, or a negative value to create a timer source.
 * @param events Events to check for.
 * @param timeout Max time in ms to wait before the callback is called,
 *                or -1 to wait indefinitely.
 * @param cb Callback function to add. Must not be NULL.
 * @param cb_data Data for the callback function. Can be NULL.
 *
 * @retval SR_OK Success.
 * @retval SR_ERR_ARG Invalid argument.
 *
 * @since 0.3.0
 * @private
 */
SR_PRIV int sr_session_source_add(struct sr_session *session, int fd,
        int events, int timeout, sr_receive_data_callback cb, void *cb_data)

/** Type definition for callback function for data reception. */
typedef int (*sr_receive_data_callback)(int fd, int revents, void *cb_data);

memset(devc->logic_data, 0x00, size);
for (i = 0; i < size; i += devc->logic_unitsize) {
    for (j = 0; j < devc->logic_unitsize; j++) {
        pat = pattern_sigrok[(devc->step + j) % sizeof(pattern_sigrok)] >> 1;
        devc->logic_data[i + j] = ~pat;
    }
    devc->step++;
}

static const uint8_t pattern_sigrok[] = {
    0x4c, 0x92, 0x92, 0x92, 0x64, 0x00, 0x00, 0x00,
    0x82, 0xfe, 0xfe, 0x82, 0x00, 0x00, 0x00, 0x00,
    0x7c, 0x82, 0x82, 0x92, 0x74, 0x00, 0x00, 0x00,
    0xfe, 0x12, 0x12, 0x32, 0xcc, 0x00, 0x00, 0x00,
    0x7c, 0x82, 0x82, 0x82, 0x7c, 0x00, 0x00, 0x00,
    0xfe, 0x10, 0x28, 0x44, 0x82, 0x00, 0x00, 0x00,
    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
    0xbe, 0xbe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};