From 0487fff76632ec023d394a05b82e87a971db8c03 Mon Sep 17 00:00:00 2001 From: Stanley Chu Date: Thu, 28 Mar 2019 17:16:25 +0800 Subject: scsi: ufs: Fix regulator load and icc-level configuration Currently if a regulator has "-fixed-regulator" property in device tree, it will skip current limit initialization. This lead to a zero "max_uA" value in struct ufs_vreg. However, "regulator_set_load" operation shall be required on regulators which have valid current limits, otherwise a zero "max_uA" set by "regulator_set_load" may cause unexpected behavior when this regulator is enabled or set as high power mode. Similarly, in device's icc_level configuration flow, the target icc_level shall be updated if regulator also has valid current limit, otherwise a wrong icc_level will be calculated by zero "max_uA" and thus causes unexpected results after it is written to device. Signed-off-by: Stanley Chu Reviewed-by: Avri Altman Acked-by: Alim Akhtar Signed-off-by: Martin K. Petersen --- drivers/scsi/ufs/ufshcd.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'drivers/scsi/ufs') diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 81d99aebb867..5ba49c8cd2a3 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -6294,19 +6294,19 @@ static u32 ufshcd_find_max_sup_active_icc_level(struct ufs_hba *hba, goto out; } - if (hba->vreg_info.vcc) + if (hba->vreg_info.vcc && hba->vreg_info.vcc->max_uA) icc_level = ufshcd_get_max_icc_level( hba->vreg_info.vcc->max_uA, POWER_DESC_MAX_ACTV_ICC_LVLS - 1, &desc_buf[PWR_DESC_ACTIVE_LVLS_VCC_0]); - if (hba->vreg_info.vccq) + if (hba->vreg_info.vccq && hba->vreg_info.vccq->max_uA) icc_level = ufshcd_get_max_icc_level( hba->vreg_info.vccq->max_uA, icc_level, &desc_buf[PWR_DESC_ACTIVE_LVLS_VCCQ_0]); - if (hba->vreg_info.vccq2) + if (hba->vreg_info.vccq2 && hba->vreg_info.vccq2->max_uA) icc_level = ufshcd_get_max_icc_level( hba->vreg_info.vccq2->max_uA, icc_level, @@ -7004,6 +7004,15 @@ static int ufshcd_config_vreg_load(struct device *dev, struct ufs_vreg *vreg, if (!vreg) return 0; + /* + * "set_load" operation shall be required on those regulators + * which specifically configured current limitation. Otherwise + * zero max_uA may cause unexpected behavior when regulator is + * enabled or set as high power mode. + */ + if (!vreg->max_uA) + return 0; + ret = regulator_set_load(vreg->reg, ua); if (ret < 0) { dev_err(dev, "%s: %s set load (ua=%d) failed, err=%d\n", -- cgit v1.2.3-59-g8ed1b