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Message-ID: <1cfa6656-8130-ce1d-e28e-3665f12cc76a@quicinc.com>
Date:   Mon, 31 Jul 2023 11:05:28 +0530
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Subject: Re: [PATCH v4 3/9] PCI: epf-mhi: Add support for handling D-state
 notify from EPC
Content-Language: en-US
To:     Manivannan Sadhasivam <mani@kernel.org>
CC:     <manivannan.sadhasivam@linaro.org>, <helgaas@kernel.org>,
        <linux-pci@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <quic_vbadigan@quicinc.com>,
        <quic_nitegupt@quicinc.com>, <quic_skananth@quicinc.com>,
        <quic_ramkri@quicinc.com>, <krzysztof.kozlowski@linaro.org>,
        "Lorenzo Pieralisi" <lpieralisi@kernel.org>,
        =?UTF-8?Q?Krzysztof_Wilczy=c5=84ski?= <kw@linux.com>,
        Kishon Vijay Abraham I <kishon@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Jeffrey Hugo <quic_jhugo@quicinc.com>,
        "open list:MHI BUS" <mhi@lists.linux.dev>
References: <1689232218-28265-1-git-send-email-quic_krichai@quicinc.com>
 <1689232218-28265-4-git-send-email-quic_krichai@quicinc.com>
 <20230728040949.GF4433@thinkpad>
From:   Krishna Chaitanya Chundru <quic_krichai@quicinc.com>
In-Reply-To: <20230728040949.GF4433@thinkpad>
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On 7/28/2023 9:39 AM, Manivannan Sadhasivam wrote:
> On Thu, Jul 13, 2023 at 12:40:12PM +0530, Krishna chaitanya chundru wrote:
>> Add support for handling D-state notify for MHI EPF.
>>
>> Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
>> ---
>>   drivers/pci/endpoint/functions/pci-epf-mhi.c | 11 +++++++++++
>>   include/linux/mhi_ep.h                       |  3 +++
>>   2 files changed, 14 insertions(+)
>>
>> diff --git a/drivers/pci/endpoint/functions/pci-epf-mhi.c b/drivers/pci/endpoint/functions/pci-epf-mhi.c
>> index 9c1f5a1..ee91bfc 100644
>> --- a/drivers/pci/endpoint/functions/pci-epf-mhi.c
>> +++ b/drivers/pci/endpoint/functions/pci-epf-mhi.c
>> @@ -339,6 +339,16 @@ static int pci_epf_mhi_bme(struct pci_epf *epf)
>>   	return 0;
>>   }
>>   
>> +static int pci_epf_mhi_dstate_notify(struct pci_epf *epf, pci_power_t state)
>> +{
>> +	struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
>> +	struct mhi_ep_cntrl *mhi_cntrl = &epf_mhi->mhi_cntrl;
>> +
>> +	mhi_cntrl->dstate = state;
> Where is this variable being used? Also, don't we need any locking?
>
> - Mani

we are using this variable in wakeup host op which is introduced on 
patch [PATCH v4 8/9] PCI: epf-mhi: Add wakeup host op

I will add lock in my next series.

- KC

>
>> +
>> +	return 0;
>> +}
>> +
>>   static int pci_epf_mhi_bind(struct pci_epf *epf)
>>   {
>>   	struct pci_epf_mhi *epf_mhi = epf_get_drvdata(epf);
>> @@ -394,6 +404,7 @@ static struct pci_epc_event_ops pci_epf_mhi_event_ops = {
>>   	.link_up = pci_epf_mhi_link_up,
>>   	.link_down = pci_epf_mhi_link_down,
>>   	.bme = pci_epf_mhi_bme,
>> +	.dstate_notify = pci_epf_mhi_dstate_notify,
>>   };
>>   
>>   static int pci_epf_mhi_probe(struct pci_epf *epf,
>> diff --git a/include/linux/mhi_ep.h b/include/linux/mhi_ep.h
>> index f198a8a..c3a0685 100644
>> --- a/include/linux/mhi_ep.h
>> +++ b/include/linux/mhi_ep.h
>> @@ -8,6 +8,7 @@
>>   
>>   #include <linux/dma-direction.h>
>>   #include <linux/mhi.h>
>> +#include <linux/pci.h>
>>   
>>   #define MHI_EP_DEFAULT_MTU 0x8000
>>   
>> @@ -139,6 +140,8 @@ struct mhi_ep_cntrl {
>>   
>>   	enum mhi_state mhi_state;
>>   
>> +	pci_power_t dstate;
>> +
>>   	u32 max_chan;
>>   	u32 mru;
>>   	u32 event_rings;
>> -- 
>> 2.7.4
>>