linux-kernel - Re: [PATCH v3] mmc: sdhci-msm: Correctly set the load for the regulator

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Message-ID: <5q4wxz52mq6b73chi3o3xtspqbczycboeqiqsqnse6qg3vvbya@ih5rac2jqsrb>
Date: Thu, 26 Dec 2024 23:04:11 +0200
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Yuanjie Yang <quic_yuanjiey@...cinc.com>
Cc: adrian.hunter@...el.com, ulf.hansson@...aro.org, 
	linux-arm-msm@...r.kernel.org, linux-mmc@...r.kernel.org, linux-kernel@...r.kernel.org, 
	andersson@...nel.org, quic_tingweiz@...cinc.com, quic_zhgao@...cinc.com
Subject: Re: [PATCH v3] mmc: sdhci-msm: Correctly set the load for the
 regulator

On Thu, Dec 26, 2024 at 11:18:45AM +0800, Yuanjie Yang wrote:
> Qualcomm regulator supports two power supply modes: HPM and LPM.
> Currently, the sdhci-msm.c driver does not set the load to adjust
> the current for eMMC and SD. If the regulator dont't set correct
> load in LPM state, it will lead to the inability to properly
> initialize eMMC and SD.
> 
> Set the correct regulator current for eMMC and SD to ensure that the
> device can work normally even when the regulator is in LPM.
> 
> Signed-off-by: Yuanjie Yang <quic_yuanjiey@...cinc.com>
> ---
> Changes in v3:
> - Optimize the code logic and separate code for regulator vmmc and vqmmc
> - Rebase on tag: next-20241217

10 days old branch

> - Link to v2: https://lore.kernel.org/all/20241127095029.3918290-1-quic_yuanjiey@quicinc.com/
> 
> Changes in v2:
> - Add enum msm_reg_type to optimize the code
> - Delete redundant emmc type judgment
> - Link to v1: https://lore.kernel.org/linux-arm-msm/20241122075048.2006894-1-quic_yuanjiey@quicinc.com/
> 
> ---
>  drivers/mmc/host/sdhci-msm.c | 64 ++++++++++++++++++++++++++++++++++--
>  1 file changed, 62 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index e00208535bd1..22811964ba61 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -134,9 +134,18 @@
>  /* Timeout value to avoid infinite waiting for pwr_irq */
>  #define MSM_PWR_IRQ_TIMEOUT_MS 5000
>  
> +/* Max load for eMMC Vdd supply */
> +#define MMC_VMMC_MAX_LOAD_UA	570000
> +
>  /* Max load for eMMC Vdd-io supply */
>  #define MMC_VQMMC_MAX_LOAD_UA	325000
>  
> +/* Max load for SD Vdd supply */
> +#define SD_VMMC_MAX_LOAD_UA	800000
> +
> +/* Max load for SD Vdd-io supply */
> +#define SD_VQMMC_MAX_LOAD_UA	22000
> +
>  #define msm_host_readl(msm_host, host, offset) \
>  	msm_host->var_ops->msm_readl_relaxed(host, offset)
>  
> @@ -1403,11 +1412,59 @@ static int sdhci_msm_set_pincfg(struct sdhci_msm_host *msm_host, bool level)
>  	return ret;
>  }
>  
> -static int sdhci_msm_set_vmmc(struct mmc_host *mmc)
> +static void msm_config_vmmc_regulator(struct mmc_host *mmc, bool hpm)
> +{
> +	int load;
> +
> +	if (!mmc->card) {
> +		regulator_set_mode(mmc->supply.vmmc,
> +				   hpm ? REGULATOR_MODE_NORMAL : REGULATOR_MODE_IDLE);

Can there be other users of the regulator or is it an exclusive one?
Because if there can be other users, you could have pulled the power
from them.

> +		return;
> +	}
> +
> +	if (!mmc_card_mmc(mmc->card) &&
> +	    !mmc_card_sd(mmc->card))
> +		return;
> +
> +	if (mmc_card_mmc(mmc->card))
> +		load = MMC_VMMC_MAX_LOAD_UA;
> +	else if (mmc_card_sd(mmc->card))
> +		load =  SD_VMMC_MAX_LOAD_UA;

if (mmc_card_mmc(mmc->card) ||
    mmc_card_sd(mmc->card))

> +	load = hpm ? load : 0;
> +
> +	regulator_set_load(mmc->supply.vmmc, load);
> +
> +	return;
> +}
> +
> +static void msm_config_vqmmc_regulator(struct mmc_host *mmc, bool hpm)
> +{
> +	int load;
> +
> +	if (!mmc->card) {
> +		regulator_set_mode(mmc->supply.vqmmc,
> +				   hpm ? REGULATOR_MODE_NORMAL : REGULATOR_MODE_IDLE);
> +		return;
> +	}
> +
> +	if (!mmc_card_sd(mmc->card))
> +		return;
> +
> +	load =  hpm ? SD_VQMMC_MAX_LOAD_UA : 0;
> +
> +	regulator_set_load(mmc->supply.vqmmc, load);
> +
> +	return;
> +}
> +
> +static int sdhci_msm_set_vmmc(struct sdhci_msm_host *msm_host,
> +			      struct mmc_host *mmc, bool hpm)
>  {
>  	if (IS_ERR(mmc->supply.vmmc))
>  		return 0;
>  
> +	msm_config_vmmc_regulator(mmc, hpm);
> +
>  	return mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd);
>  }
>  
> @@ -1420,6 +1477,8 @@ static int msm_toggle_vqmmc(struct sdhci_msm_host *msm_host,
>  	if (msm_host->vqmmc_enabled == level)
>  		return 0;
>  
> +	msm_config_vqmmc_regulator(mmc, level);
> +
>  	if (level) {
>  		/* Set the IO voltage regulator to default voltage level */
>  		if (msm_host->caps_0 & CORE_3_0V_SUPPORT)
> @@ -1642,7 +1701,8 @@ static void sdhci_msm_handle_pwr_irq(struct sdhci_host *host, int irq)
>  	}
>  
>  	if (pwr_state) {
> -		ret = sdhci_msm_set_vmmc(mmc);
> +		ret = sdhci_msm_set_vmmc(msm_host, mmc,
> +					 pwr_state & REQ_BUS_ON);
>  		if (!ret)
>  			ret = sdhci_msm_set_vqmmc(msm_host, mmc,
>  					pwr_state & REQ_BUS_ON);
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry