Subject: Re: [RFC PATCH 1/4] mmc: core: add cap-enhanced-strobe support
To: Jaehoon Chung <jh80.chung@samsung.com>,
        Shawn Lin <shawn.lin@rock-chips.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Ulf Hansson <ulf.hansson@linaro.org>
References: <1456972557-7994-1-git-send-email-shawn.lin@rock-chips.com>
 <1456972585-8036-1-git-send-email-shawn.lin@rock-chips.com>
 <56D82934.3040205@samsung.com>
Cc: Michal Simek <michal.simek@xilinx.com>, soren.brinkmann@xilinx.com,
        linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org
From: Shawn Lin <shawn.lin@rock-chips.com>
Message-ID: <56D8E74B.3010603@rock-chips.com>
Date: Fri, 4 Mar 2016 09:39:23 +0800
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:38.0) Gecko/20100101
 Thunderbird/38.6.0
MIME-Version: 1.0
In-Reply-To: <56D82934.3040205@samsung.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1769
Lines: 60

Hi Jaehoon,

On 2016/3/3 20:08, Jaehoon Chung wrote:
> Hi Shawn,
>
> On 03/03/2016 11:36 AM, Shawn Lin wrote:
>> This patch introduce cap-enhanced-strobe for platforms which
>> want to enable enhanced strobe function from DT if the mmc host
>> controller claims to support enhanced strobe.
>
> I don't know why need to add the capability and property.
>

 From my point, HS400-ES is a optional feature, so we should leave it
for people to decide whether to use it. Just as my controller supports 
hs400, but I can't force all the people using my platform to use hs400?
That's why we add mmc-hs400-* in DT.

But maybe I can change the name to mmc-hs400es-* ?


[...]

>>   #define MMC_CAP_DRIVER_TYPE_A	(1 << 23)	/* Host supports Driver Type A */
>>   #define MMC_CAP_DRIVER_TYPE_C	(1 << 24)	/* Host supports Driver Type C */
>>   #define MMC_CAP_DRIVER_TYPE_D	(1 << 25)	/* Host supports Driver Type D */
>> +#define MMC_CAP_ENHANCED_STROBE	(1 << 20)	/* Host supports enhanced strobe */
>
> Need to fix ordering.

yeah~~ good catch!

>
>>   #define MMC_CAP_CMD23		(1 << 30)	/* CMD23 supported. */
>>   #define MMC_CAP_HW_RESET	(1 << 31)	/* Hardware reset */
>>
>> @@ -469,6 +470,11 @@ static inline int mmc_host_uhs(struct mmc_host *host)
>>   		 MMC_CAP_UHS_DDR50);
>>   }
>>
>> +static inline int mmc_host_enhanced_strobe(struct mmc_host *host)
>> +{
>> +	return host->caps & MMC_CAP_ENHANCED_STROBE;
>> +}
>> +
>>   static inline int mmc_host_packed_wr(struct mmc_host *host)
>>   {
>>   	return host->caps2 & MMC_CAP2_PACKED_WR;
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>


-- 
Best Regards
Shawn Lin