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SubjectRe: [PATCH 1/4] mfd: mc13783: Take care of semantic inversion between read and write value of two bits in POWER_MISCELLANEUS register.
On Sat, Dec 12, 2009 at 05:48:43PM +0100, Alberto Panizzo wrote:
> MC13783_REGCTRL_PWGTnSPIEN controls the states of the corresponding
> PWGTn_DRV output.
> Reading 1 on the corresponding bit mean that the output is enabled
> Writing 1 on the corresponding bit disable that output!
>
> So, if not asked directly to modify those bits, write the inverted
> value.
Hmm, I'm not sure this completely right. The Spec has:

Bit PWGTxSPIEN | Pin PWGTxEN | PWGTxDRV | Read Back
0 = default | | | PWGTxSPIEN
---------------+-------------+----------+------------
1 | x | Low | 0
0 | 0 | High | 1
0 | 1 | Low | 0
So it looks a bit harder than just inverting the read bit.

Best regards
Uwe

--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | http://www.pengutronix.de/ |
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