Difference between revisions of "TSC2102 Linux driver"

Revision as of 09:19, 18 November 2008

This page details the installation and the usage of the Linux drivers for the TSC2102 touchscreen & sound chip. Sound (ALSA) specific part can be found here.

Driver Installation

$ make linux-menuconfig

in Device Drivers  ---> Input device support  ---> select <*>   Event interface  as builtin
in Device Drivers  ---> Input device support  ---> [*]   Touchscreens  ---> select <M>   TSC 2102 based touchscreens as module

in Device Drivers  ---> SPI support  --->  select <M> Freescale iMX SPI controller as module
in Device Drivers  ---> SPI support  ---> --- TSC2102 codec support should be selected

in Device Drivers  ---> select <M> Hardware Monitoring support  ---> as module

$ make linux

Then reflash your Linux kernel and your Rootfs...

Architecture

Usage

• load all the needed drivers:

# modprobe spi_imx
# modprobe tsc2102_ts
TI TSC2102 driver initializing
input: TSC2102 Touchscreen as /class/input/input0
TSC2102 touchscreen driver initialized

• To check:

# lsmod
Module                  Size  Used by    Not tainted
tsc2102_ts              1188  0
tsc2102                10192  3 tsc2102_ts
hwmon                    916  1 tsc2102
spi_imx                 7136  0

Then, you can:

• get temperature and voltage with hwmon (Hardware Monitoring) interface. For example:

# cat /sys/class/hwmon/hwmon0/device/temp1_input    -- result in m°C

• play sounds through ALSA interface
• use touchscreen with Tslib

TSLib API Installation

Install the Tslib touchscreen API

Envt variables

• You should define some ENVT variables to use the touchscreen API (tslib):

export TSLIB_TSDEVICE=/dev/input/event0
export TSLIB_TSEVENTTYPE=INPUT
export TSLIB_CONFFILE=/etc/ts.conf
export TSLIB_CALIBFILE=/etc/pointercal

• you can add them to your /etc/profile:

# vi /etc/profile

Device file creation if not exist

• /dev/input/event0 is created from the infos got from:

# cat /sys/class/input/event0/dev
13:64
# mkdir /dev/input
# cd /dev/input/
# mknod event0 c 13 64
# ls -al
drwxr-xr-x    2 root     root            0 Jan  1 00:39 .
drwxr-xr-x    5 root     root            0 Jan  1 00:39 ..
crw-r--r--    1 root     root      13,  64 Jan  1 00:39 event0
#

Quick test

To quickly check driver fonctionnality, touch the screen and check that tsc2102 interrupts count is increasing:

# cat /proc/interrupts
          CPU0
26:          0         MPU  IMX-uart
29:         17         MPU  IMX-uart
30:         22         MPU  IMX-uart
35:         12         MPU  imx-mmc
39:         14         MPU  I2C_IMX
40:         16         MPU  imx-spi.2
41:          0         MPU  imx-spi.1
59:       3682         MPU  i.MX Timer Tick
60:          0         MPU  DMA
61:          0         MPU  DMA
110:         0        GPIO  eth0
168:         0        GPIO  tsc2102
Err:         0
#

or start the touchscreen calibration tool:

/usr/bin/ts_calibrate

Links

• http://source.mvista.com/git/gitweb.cgi?p=linux-omap-2.6.git;a=log;t=7 (search for TSC2102)
• http://osdir.com/ml/linux.ports.arm.omap/2006-08/msg00183.html
• Touchscreen usage on Blackfin
• Compiling TSlib
• http://www.opentom.org/Tslib
• http://www.openembedded.org/filebrowser/org.openembedded.packaged-staging/packages/tslib