Dear Todd Fischer, Nicolas Luna and Sekhar, hello group,
>Todd Fischer todd.fischer at ridgerun.com
>Thu Jul 29 06:43:10 CDT 2010
>
>Nicolas,
>
>Also, due to another hardware limitation, the touch screen driver using
>polling instead of interrupts. I heard a hardware change that will
>allow for interrupts to be used is planned as well. The polling
>overhead costs around 2% ARM CPU.
>
>Todd
By now there is new OMAPL-138 SOM hardware available,
SOMOMAPL138-10-1502QHCR or SOMOMAPL138-10-1602QHIR-A for example. Are
there plans to integrate an interrupt driven mode into the driver?
We have seen this issue on a 2.6.33_rc4 kernel. And after porting to
2.6.38 we can paralyse the i2c bus by action on the touchscreen
much faster.
In this state the SDA line is hold low and the driver gives repeatedly
the following messages:
tps6507x 1-0048: ADC result 1 read failed
i2c_davinci i2c_davinci.1: controller timed out
i2c_davinci i2c_davinci.1: initiating i2c bus recovery
i2c_davinci i2c_davinci.1: controller timed out
i2c_davinci i2c_davinci.1: initiating i2c bus recovery
tps6507x 1-0048: TSC mode read failed
i2c_davinci i2c_davinci.1: controller timed out
i2c_davinci i2c_davinci.1: initiating i2c bus recovery
i2c_davinci i2c_davinci.1: controller timed out
i2c_davinci i2c_davinci.1: initiating i2c bus recovery
tps6507x 1-0048: TSC mode read failed
[...]
Nicolas Luna have had similar problems and perhaps found a solution with a
davinci-i2c kernel Patch. (please see
http://e2e.ti.com/support/power_management/pmu/f/200/p/58632/208908.aspx#208908
and
http://www.mail-archive.com/davinci-linux-open-source@linux.davincidsp.com/msg19179.html
)
This patch mentioned above has been applied to our 2.6.38 kernel tree based on
kernelorg in commit 4bba0fd8d1c6d405df666e2573e1a1f917098be0 but we
still have problems with that issue.
Nicolas, please tell me in which kernel tree you were satisfied with the
touchscreen and i2c drivers.
Thank you,
regards,
Bastian Ruppert.
_______________________________________________
Davinci-linux-open-source mailing list
Davinci-linux-open-source@linux.davincidsp.com
http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
