static int cs_hsi_write_on_control()

in clients/cmt_speech.c [526:571]

• 35 lines of code
• 5 McCabe index (conditional complexity)

static int cs_hsi_write_on_control(struct cs_hsi_iface *hi, u32 message)
{
	struct hsi_msg *msg;
	int ret;

	spin_lock(&hi->lock);
	if (hi->control_state & SSI_CHANNEL_STATE_ERROR) {
		spin_unlock(&hi->lock);
		return -EIO;
	}
	if (hi->control_state & SSI_CHANNEL_STATE_WRITING) {
		dev_err(&hi->cl->device,
			"Write still pending on control channel.\n");
		spin_unlock(&hi->lock);
		return -EBUSY;
	}
	hi->control_state |= SSI_CHANNEL_STATE_WRITING;
	msg = cs_claim_cmd(hi);
	spin_unlock(&hi->lock);

	cs_set_cmd(msg, message);
	msg->sgt.nents = 1;
	msg->complete = cs_hsi_write_on_control_complete;
	dev_dbg(&hi->cl->device,
		"Sending control message %08X\n", message);
	ret = hsi_async_write(hi->cl, msg);
	if (ret) {
		dev_err(&hi->cl->device,
			"async_write failed with %d\n", ret);
		cs_hsi_control_write_error(hi, msg);
	}

	/*
	 * Make sure control read is always pending when issuing
	 * new control writes. This is needed as the controller
	 * may flush our messages if e.g. the peer device reboots
	 * unexpectedly (and we cannot directly resubmit a new read from
	 * the message destructor; see cs_cmd_destructor()).
	 */
	if (!(hi->control_state & SSI_CHANNEL_STATE_READING)) {
		dev_err(&hi->cl->device, "Restarting control reads\n");
		cs_hsi_read_on_control(hi);
	}

	return 0;
}