Wiki

Below is the source of this page. To edit this source as well as other pages on the wiki, you must login.
====== iio-trig-bfin-timer driver ======

===== Description =====

This driver allows any Blackfin system timer to be used as IIO trigger.
It supports trigger rates from 0 to 100kHz in Hz resolution.

<WRAP tip>
This driver depends on BLACKFIN
</WRAP>

====== Adding Linux driver support ======

Configure kernel with “make menuconfig” (alternatively use “make xconfig” or “make qconfig”) 

<code>
Linux Kernel Configuration
	Device Drivers  --->
		[*] Staging drivers  --->
			<*>     Industrial I/O support  --->
			    --- Industrial I/O support
			    -*-   Enable ring buffer support within IIO
			    -*-     Industrial I/O lock free software ring
			    -*-   Enable triggered sampling support
			    
			    [--snip--]
			    
			          *** Triggers - standalone ***
			    < >   Periodic RTC triggers
			    < >   GPIO trigger
			    < >   SYSFS trigger
			    <*>   Blackfin TIMER trigger
</code>

====== Example platform device initialization ======

One or multiple instances of this driver can be declared by adding appropriate platform device data.
An example is shown below:

<code c>
static struct resource iio_bfin_trigger_resources[] = {
	{
		.start = IRQ_TIMER3,
		.end = IRQ_TIMER3,
		.flags = IORESOURCE_IRQ,
	},
};

static struct platform_device iio_bfin_trigger = {
	.name		= "iio_bfin_tmr_trigger",
	.id		= 0,
	.num_resources	= ARRAY_SIZE(iio_bfin_trigger_resources),
	.resource	= iio_bfin_trigger_resources,
};
</code>

<code c>
static struct platform_device *board_devices[] __initdata = {
	&iio_bfin_trigger
};
</code>


<code c>
static int __init board_init(void)
{
	[--snip--]
	
	platform_add_devices(board_devices, ARRAY_SIZE(board_devices));
	
	[--snip--]

	return 0;
}
arch_initcall(board_init);
</code>

====== Driver testing ======

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/> **cd sys/bus/iio/devices/**
root:/sys/bus/iio/devices> **ls**
device0                  device0:buffer0:event0   device1:buffer0:access0
device0:buffer0          device1                  device1:buffer0:event0
device0:buffer0:access0  device1:buffer0          trigger0
</xterm></WRAP>


<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/bus/iio/devices> **cd trigger0**
root:/sys/devices/trigger0> **ls**
name         subsystem    frequency  uevent
</xterm></WRAP>

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/devices/trigger0> **cat name**
bfintmr3
</xterm></WRAP>

<WRAP box bggreen><wrap info>This specifies any shell prompt running on the target</wrap>
<xterm>
root:/sys/devices/trigger0> **echo 1000 > frequency**
root:/sys/devices/trigger0> **echo 0 > frequency**
</xterm></WRAP>
Analog Devices Wiki

Page Tools
