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Message-ID: <4697e12b-e9e3-100e-190c-7eece43b3a05@linaro.org>
Date:   Tue, 2 Aug 2022 12:59:30 +0200
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Subject: Re: [PATCH 2/3] drivers: bus: simple-pm-bus: Use clocks
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From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To:     Liu Ying <victor.liu@nxp.com>, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org,
        shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de,
        festevam@gmail.com, linux-imx@nxp.com, saravanak@google.com,
        gregkh@linuxfoundation.org, geert+renesas@glider.be
References: <20220802071310.2650864-1-victor.liu@nxp.com>
 <20220802071310.2650864-3-victor.liu@nxp.com>
 <7b0d5f68-491e-ace4-5970-92ef795ec5a7@linaro.org>
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On 02/08/2022 12:56, Krzysztof Kozlowski wrote:
> On 02/08/2022 09:13, Liu Ying wrote:
>> Simple Power-Managed bus controller may need functional clock(s)
>> to be enabled before child devices connected to the bus can be
>> accessed.  Get the clock(s) as a bulk and enable/disable the
>> clock(s) when the bus is being power managed.
>>
>> One example is that Freescale i.MX8qxp pixel link MSI bus controller
>> needs MSI clock and AHB clock to be enabled before accessing child
>> devices.
> 
> No, because it is not simple bus anymore.

Hm, actually I take back my no, as this pm-bus was done for such
purpose. Since we allow power domains, we should also allow clocks.

Best regards,
Krzysztof