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[Bug 1001437] New: ADC HW drivers have race condition incyg_io_set_config(CYG_IO_SET_CONFIG_ADC_[EN|DIS]ABLE)

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           Summary: ADC HW drivers have race condition in
           Product: eCos
           Version: CVS
          Platform: All
        OS/Version: All
            Status: UNCONFIRMED
          Severity: major
          Priority: low
         Component: ADC
             Class: Advice Request


While looking at the source code of the LPC2XXX ADC driver, and after having
checked other ADC hardware drivers, it seems that all of these drivers, when
the following processing:

xxx_adc_disable(cyg_adc_channel *chan)
  xxx_adc_info *info=chan->device->dev_priv;


  info->chan_mask &= [some code to get bit value for concerned channel];

The opposite, for xxx_adc_enable(), is done with "info->chan_mask |= ..."

In multi-thread, if more than one thread handle ADC channels, since
info->chan_mask points, for all channels, to the same data area, then a thread
may be interrupted in the middle of the read-modify-write operation to update
the bit/channel field. Another thread can be scheduled and do its own
read-modify-write op on the same area.

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