Re: [v4] rtc: pcf85363/pcf85263: fix error that failed to run hwclock -w
From: Nandor Han
Date: Tue Aug 27 2019 - 04:07:35 EST
On 8/27/19 7:37 AM, Biwen Li wrote:
- In drivers/rtc/rtc-pcf85363.c, CTRL_STOP_EN is 0x2e, but DT_100THS
is 0, max_regiter is 0x2f, then reg will be equal to 0x30,
'0x30 < 0x2f' is false,so regmap_writeable will return false.
- The pcf85363/pcf85263 has the capability of address wrapping
which means if you access a continuous address range across a
certain boundary(max_register of struct regmap_config) the
hardware actually wraps the access to a lower address. But the
address violation check of regmap rejects such access.
nitpick: This 2 paragraphs could be combined to clear up the issue:
The pcf85363/pcf85263 has the capability of address wrapping
which means if you access an address outside the allowed range
(0x00-0x2f) the hardware actually wraps the access to a lower address.
The rtc-pf85363 driver will use this feature to configure the time and
execute 2 actions in the same i2c write operation (stopping the clock
and configure the time). However the driver has also configured the
`regmap maxregister` protection mechanism that will block accessing
addresses outside valid range (0x00-0x2f).
nitpick: I would also use separate buffers for this actions. Up to you :)
Otherwise LGTM +1