spike_queue_spi_write

gistfile1.txt

static int spike_queue_spi_write(void)
{
	int status;
	unsigned long flags;

	spi_message_init(&spike_ctl.msg);

	/* this gets called when the spi_message completes */
	spike_ctl.msg.complete = spike_completion_handler;
	spike_ctl.msg.context = NULL;

	/* write some toggling bit patterns, doesn't really matter */	
	spike_ctl.tx_buff[0] = 0xAA;
	spike_ctl.tx_buff[1] = 0x55;

	spike_ctl.transfer.tx_buf = spike_ctl.tx_buff;
	spike_ctl.transfer.rx_buf = NULL;
	spike_ctl.transfer.len = 2;

	spi_message_add_tail(&spike_ctl.transfer, &spike_ctl.msg);

	spin_lock_irqsave(&spike_dev.spi_lock, flags);

	if (spike_dev.spi_device)
		status = spi_async(spike_dev.spi_device, &spike_ctl.msg);
	else
		status = -ENODEV;

	spin_unlock_irqrestore(&spike_dev.spi_lock, flags);
	
	if (status == 0)
		spike_ctl.busy = 1;
	
	return status;	
}