Re: [PATCH V2 0/2] mmc: sdhci-sprd: Add SD HS mode online tuning

[Adrian Hunter]

On 15/08/23 13:55, Wenchao Chen wrote:
> On Tue, Aug 15, 2023 at 6:37 PM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>>
>> On 15/08/23 13:29, Wenchao Chen wrote:
>>> On Tue, Aug 15, 2023 at 2:21 PM Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>>>>
>>>> On 15/08/23 04:40, Wenchao Chen wrote:
>>>>> Change in v2:
>>>>> - add mmc_sd_switch() and mmc_send_status() to the header file
>>>>> - split up core changes from host driver changes
>>>>> - Use pr_debug instead of dev_info and dev_dbg
>>>>> - Optimize the best sampled value algorithm
>>>>
>>>> What about hooking ->set_ios() as Ulf suggested?
>>>>
>>>
>>> I've tried that, but it's not a good way to do it.
>>> We found that sdhci_runtime_resume_host() calls ->set_ios, but we
>>> don't want to do that.
>>
>> Given that sdhci_sprd_runtime_resume() calls sdhci_runtime_resume_host(),
>> it should be possible to determine when to tune, right?
>>
> 
> You mean like this? For example:
> static int sdhci_sprd_runtime_resume(struct device *dev)
> {
> ...
> sprd_host->need_hs_tuning = false;
> sdhci_runtime_resume_host(host, 1);
> sprd_host->need_hs_tuning = true;

Yes

> ...
> }
> 
>>> We just need SD HS mode tuning at mmc_sd_init_card().
>>>
>>>>>
>>>>> Wenchao Chen (2):
>>>>>   mmc: core: Add host specific tuning support for SD HS mode
>>>>>   mmc: sdhci-sprd: Add SD HS mode online tuning
>>>>>
>>>>>  drivers/mmc/core/sd.c         |  12 +++
>>>>>  drivers/mmc/core/sd_ops.c     |   1 +
>>>>>  drivers/mmc/host/sdhci-sprd.c | 152 ++++++++++++++++++++++++++++++++++
>>>>>  include/linux/mmc/host.h      |   8 ++
>>>>>  4 files changed, 173 insertions(+)
>>>>>
>>>>
>>