static int do_bank_switch()

in stream.c [760:866]

• 76 lines of code
• 15 McCabe index (conditional complexity)

static int do_bank_switch(struct sdw_stream_runtime *stream)
{
	struct sdw_master_runtime *m_rt;
	const struct sdw_master_ops *ops;
	struct sdw_bus *bus;
	bool multi_link = false;
	int m_rt_count;
	int ret = 0;

	m_rt_count = stream->m_rt_count;

	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
		bus = m_rt->bus;
		ops = bus->ops;

		if (bus->multi_link && m_rt_count >= bus->hw_sync_min_links) {
			multi_link = true;
			mutex_lock(&bus->msg_lock);
		}

		/* Pre-bank switch */
		if (ops->pre_bank_switch) {
			ret = ops->pre_bank_switch(bus);
			if (ret < 0) {
				dev_err(bus->dev,
					"Pre bank switch op failed: %d\n", ret);
				goto msg_unlock;
			}
		}

		/*
		 * Perform Bank switch operation.
		 * For multi link cases, the actual bank switch is
		 * synchronized across all Masters and happens later as a
		 * part of post_bank_switch ops.
		 */
		ret = sdw_bank_switch(bus, m_rt_count);
		if (ret < 0) {
			dev_err(bus->dev, "Bank switch failed: %d\n", ret);
			goto error;
		}
	}

	/*
	 * For multi link cases, it is expected that the bank switch is
	 * triggered by the post_bank_switch for the first Master in the list
	 * and for the other Masters the post_bank_switch() should return doing
	 * nothing.
	 */
	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
		bus = m_rt->bus;
		ops = bus->ops;

		/* Post-bank switch */
		if (ops->post_bank_switch) {
			ret = ops->post_bank_switch(bus);
			if (ret < 0) {
				dev_err(bus->dev,
					"Post bank switch op failed: %d\n",
					ret);
				goto error;
			}
		} else if (multi_link) {
			dev_err(bus->dev,
				"Post bank switch ops not implemented\n");
			goto error;
		}

		/* Set the bank switch timeout to default, if not set */
		if (!bus->bank_switch_timeout)
			bus->bank_switch_timeout = DEFAULT_BANK_SWITCH_TIMEOUT;

		/* Check if bank switch was successful */
		ret = sdw_ml_sync_bank_switch(bus);
		if (ret < 0) {
			dev_err(bus->dev,
				"multi link bank switch failed: %d\n", ret);
			goto error;
		}

		if (multi_link)
			mutex_unlock(&bus->msg_lock);
	}

	return ret;

error:
	list_for_each_entry(m_rt, &stream->master_list, stream_node) {
		bus = m_rt->bus;
		if (bus->defer_msg.msg) {
			kfree(bus->defer_msg.msg->buf);
			kfree(bus->defer_msg.msg);
		}
	}

msg_unlock:

	if (multi_link) {
		list_for_each_entry(m_rt, &stream->master_list, stream_node) {
			bus = m_rt->bus;
			if (mutex_is_locked(&bus->msg_lock))
				mutex_unlock(&bus->msg_lock);
		}
	}

	return ret;
}