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Linux SDK am335x-evm-05.06.00.00 suspect delay in touch screen driver interrupt

In reviewing the touch screen driver (board-support/linux-3.2.0-psp05.06.00.00/drivers/input/touchscreen/ti_tsc.c) I have found a 350 usec delay "udelay(350)" in the interrupt handler "static irqreturn_t tscadc_interrupt()" at line 252.

It would seam to me that a delay like this in an interrupt is gererally not good practice as it would hinder cpu cycles being spent on anything except a higher priority interrupt that could preempt the touchscreen interrupt.

Though a deprecated feature, the irq is registered with the IRQF_DISABLED options which, if I interpret that correctly, disables preemption while handling the tscadc_interrupt().

Is this a simple oversight, or an intentional delay that can be rationalized?

Thanks,

Stuart