xref: /kernel/linux/linux-5.10/Documentation/ABI/testing/sysfs-driver-hid-picolcd (revision 8c2ecf20)

What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/operation_mode
Date:		March 2010
Contact:	Bruno Prémont <bonbons@linux-vserver.org>
Description:	Make it possible to switch the PicoLCD device between LCD
		(firmware) and bootloader (flasher) operation modes.

		Reading: returns list of available modes, the active mode being
		enclosed in brackets ('[' and ']')

		Writing: causes operation mode switch. Permitted values are
		the non-active mode names listed when read.

		Note: when switching mode the current PicoLCD HID device gets
		disconnected and reconnects after above delay (see attribute
		operation_mode_delay for its value).


What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/operation_mode_delay
Date:		April 2010
Contact:	Bruno Prémont <bonbons@linux-vserver.org>
Description:	Delay PicoLCD waits before restarting in new mode when
		operation_mode has changed.

		Reading/Writing: It is expressed in ms and permitted range is
		0..30000ms.


What:		/sys/bus/usb/devices/<busnum>-<devnum>:<config num>.<interface num>/<hid-bus>:<vendor-id>:<product-id>.<num>/fb_update_rate
Date:		March 2010
Contact:	Bruno Prémont <bonbons@linux-vserver.org>
Description:	Make it possible to adjust defio refresh rate.

		Reading: returns list of available refresh rates (expressed in Hz),
		the active refresh rate being enclosed in brackets ('[' and ']')

		Writing: accepts new refresh rate expressed in integer Hz
		within permitted rates.

		Note: As device can barely do 2 complete refreshes a second
		it only makes sense to adjust this value if only one or two
		tiles get changed and it's not appropriate to expect the application
		to flush its tiny changes explicitly at higher than default rate.