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Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and FFCN are provided

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Hi All,

>> The current driver uses input clock source frequency to calculate
>> values for [SS|FS]_[HC|LC] registers. However, when booting ACPI, we do not
>> currently have a good way to provide the frequency information.
>> Instead, we can leverage the SSCN and FFCN ACPI methods, which can be used
>> to directly provide these values. So, the clock information should
>> no longer be required during probing.
>>
>> However, since clk can be invalid, additional checks must be done where
>> we are making use of it.
>>
>> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
>> Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
>> Tested-by: Loc Ho <lho@apm.com>
>> ---
>>
>> Note: This has been tested on AMD Seattle RevB for both DT and ACPI.
>>
>> Changes from V3 (https://lkml.org/lkml/2015/12/22/596):
>>     * Add i2c_dw_plat_prepare_clk() per Andy's suggestion
>>     * Add tested-by Loc Ho.
>
> The changes from V3 are big enough that I'd appreciate a new Tested-by
> tag.

I had tested this via this mixes of test cases:

a. NO APD driver + this patch ==> HCNT/LCNT as expected
b. with APD driver + this patch ==> HCNT/LCNT as expected
c. with APD driver + this patch + double the frequency APD driver ==>
HCNT/LCNT as expected
d. with APD driver + this patch + double the frequency APD driver +
comment out the ACPI parameter retrieve ==> HCNT/LCNT changed as
expected

Therefore, you can add my - Tested-by: Loc Ho <lho@apm.com>

-Loc
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[PATCH v4] i2c: designware: Do not require clock when SSCN and FFCN are provided Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> - 2016-01-04 16:20 +0100
  Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and  FFCN are provided Wolfram Sang <wsa@the-dreams.de> - 2016-01-04 17:20 +0100
    Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and  FFCN are provided Loc Ho <lho@apm.com> - 2016-01-05 21:00 +0100
    Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and  FFCN are provided Loc Ho <lho@apm.com> - 2016-01-07 01:40 +0100
  Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and  FFCN are provided Wolfram Sang <wsa@the-dreams.de> - 2016-01-10 09:40 +0100
    Re: [PATCH v4] i2c: designware: Do not require clock when SSCN and  FFCN are provided Suravee Suthikulanit <suravee.suthikulpanit@amd.com> - 2016-01-13 23:50 +0100

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