Re: [PATCH v1] mmc: sdhci-msm: Correctly set the load for the regulator

[Adrian Hunter <adrian.hunter@intel.com>]

On 22/11/24 09:50, 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. Therefore, if the regulator set 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@quicinc.com>
> ---
>  drivers/mmc/host/sdhci-msm.c | 91 +++++++++++++++++++++++++++++++++++-
>  1 file changed, 89 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
> index e00208535bd1..f2a2260d54c6 100644
> --- a/drivers/mmc/host/sdhci-msm.c
> +++ b/drivers/mmc/host/sdhci-msm.c
> @@ -134,9 +134,22 @@
>  /* 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 MAX_MMC_SD_VMMC_LOAD_UA  max(MMC_VMMC_MAX_LOAD_UA, SD_VMMC_MAX_LOAD_UA)
> +
> +#define MAX_MMC_SD_VQMMC_LOAD_UA max(MMC_VQMMC_MAX_LOAD_UA, SD_VQMMC_MAX_LOAD_UA)
> +
>  #define msm_host_readl(msm_host, host, offset) \
>  	msm_host->var_ops->msm_readl_relaxed(host, offset)
>  
> @@ -147,6 +160,11 @@
>  #define CQHCI_VENDOR_CFG1	0xA00
>  #define CQHCI_VENDOR_DIS_RST_ON_CQ_EN	(0x3 << 13)
>  
> +enum {

This could be a named type and used instead of 'int'
e.g.

enum msm_reg_type {

> +	VMMC_REGULATOR,
> +	VQMMC_REGULATOR,
> +};
> +
>  struct sdhci_msm_offset {
>  	u32 core_hc_mode;
>  	u32 core_mci_data_cnt;
> @@ -1403,11 +1421,70 @@ 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 int sdhci_msm_get_regulator_load(struct mmc_host *mmc, int max_current, int type)

Then 'int type' could be 'enum msm_reg_type type'

> +{
> +	int load = 0;
> +
> +	/*
> +	 * When eMMC and SD are powered on for the first time, select a higher
> +	 * current value from the corresponding current for eMMC and SD to
> +	 * ensure that the eMMC and SD cards start up properly and complete
> +	 * initialization. After the initialization process is finished, use
> +	 * the corresponding current to set the eMMC and SD to ensure the
> +	 * normal work of the device.
> +	 */
> +
> +	if (!mmc->card)
> +		return max_current;
> +
> +	if (mmc_card_is_removable(mmc) && mmc_card_mmc(mmc->card))

The comment mentions eMMC but here there is 'mmc_card_is_removable()'
whereas eMMC's are not removable.  If this is right it needs some
clarification.

> +		load = (type == VMMC_REGULATOR) ? MMC_VMMC_MAX_LOAD_UA : MMC_VQMMC_MAX_LOAD_UA;
> +	else if (mmc_card_sd(mmc->card))
> +		load = (type == VMMC_REGULATOR) ? SD_VMMC_MAX_LOAD_UA : SD_VQMMC_MAX_LOAD_UA;
> +
> +	return load;
> +}
> +
> +static int msm_config_regulator_load(struct sdhci_msm_host *msm_host, struct mmc_host *mmc,
> +				     bool hpm, int max_current, int type)

Again 'int type' could be 'enum msm_reg_type type'

> +{
> +	int ret;
> +	int load = 0;
> +
> +	/*
> +	 * After the initialization process is finished, Once the type of card
> +	 * is determined，only set the corresponding current for SD and eMMC.
> +	 */
> +
> +	if (mmc->card && !(mmc_card_mmc(mmc->card) || mmc_card_sd(mmc->card)))
> +		return 0;
> +
> +	if (hpm)
> +		load = sdhci_msm_get_regulator_load(mmc, max_current, type);
> +
> +	if (type == VMMC_REGULATOR)
> +		ret = regulator_set_load(mmc->supply.vmmc, load);
> +	else
> +		ret = regulator_set_load(mmc->supply.vqmmc, load);
> +	if (ret)
> +		dev_err(mmc_dev(mmc), "%s: set load failed: %d\n",
> +			mmc_hostname(mmc), ret);
> +	return ret;
> +}
> +
> +static int sdhci_msm_set_vmmc(struct sdhci_msm_host *msm_host,
> +			      struct mmc_host *mmc, bool hpm)
>  {
> +	int ret;
> +
>  	if (IS_ERR(mmc->supply.vmmc))
>  		return 0;
>  
> +	ret = msm_config_regulator_load(msm_host, mmc, hpm,
> +					MAX_MMC_SD_VMMC_LOAD_UA, VMMC_REGULATOR);
> +	if (ret)
> +		return ret;
> +
>  	return mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, mmc->ios.vdd);
>  }
>  
> @@ -1435,6 +1512,15 @@ static int msm_toggle_vqmmc(struct sdhci_msm_host *msm_host,
>  				goto out;
>  			}
>  		}
> +
> +		ret = msm_config_regulator_load(msm_host, mmc, level,
> +						MAX_MMC_SD_VQMMC_LOAD_UA, VQMMC_REGULATOR);
> +		if (ret < 0) {
> +			dev_err(mmc_dev(mmc), "%s: vqmmc set regulator load failed: %d\n",
> +				mmc_hostname(mmc), ret);
> +			goto out;
> +		}
> +
>  		ret = regulator_enable(mmc->supply.vqmmc);
>  	} else {
>  		ret = regulator_disable(mmc->supply.vqmmc);
> @@ -1642,7 +1728,8 @@ 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);