Messages in this thread | | | Date | Wed, 02 Dec 2020 18:16:30 +0800 | From | Can Guo <> | Subject | Re: [PATCH v3] scsi: ufs: Remove pre-defined initial voltage values of device powers |
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On 2020-12-02 17:18, Stanley Chu wrote: > UFS specficication allows different VCC configurations for UFS devices, > for example, > (1). 2.70V - 3.60V (Activated by default in UFS core driver) > (2). 1.70V - 1.95V (Activated if "vcc-supply-1p8" is declared in > device tree) > (3). 2.40V - 2.70V (Supported since UFS 3.x) > > With the introduction of UFS 3.x products, an issue is happening that > UFS driver will use wrong "min_uV-max_uV" values to configure the > voltage of VCC regulator on UFU 3.x products with the configuration (3) > used. > > To solve this issue, we simply remove pre-defined initial VCC voltage > values in UFS core driver with below reasons, > > 1. UFS specifications do not define how to detect the VCC configuration > supported by attached device. > > 2. Device tree already supports standard regulator properties. > > Therefore VCC voltage shall be defined correctly in device tree, and > shall not changed by UFS driver. What UFS driver needs to do is simply > enable or disable the VCC regulator only. > > Similar change is applied to VCCQ and VCCQ2 as well. > > Note that we keep struct ufs_vreg unchanged. This allows vendors to > configure proper min_uV and max_uV of any regulators to make > regulator_set_voltage() works during regulator toggling flow in the > future. Without specific vendor configurations, min_uV and max_uV will > be NULL by default and UFS core driver will enable or disable the > regulator only without adjusting its voltage. > > Acked-by: Avri Altman <avri.altman@wdc.com> > Reviewed-by: Asutosh Das <asutoshd@codeaurora.org> > Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
> Signed-off-by: Stanley Chu <stanley.chu@mediatek.com> > --- > drivers/scsi/ufs/ufshcd-pltfrm.c | 19 ------------------- > 1 file changed, 19 deletions(-) > > diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c > b/drivers/scsi/ufs/ufshcd-pltfrm.c > index 0619cfbfbdbb..1a69949a4ea1 100644 > --- a/drivers/scsi/ufs/ufshcd-pltfrm.c > +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c > @@ -134,25 +134,6 @@ static int ufshcd_populate_vreg(struct device > *dev, const char *name, > dev_info(dev, "%s: unable to find %s\n", __func__, prop_name); > vreg->max_uA = 0; > } > - > - if (!strcmp(name, "vcc")) { > - if (of_property_read_bool(np, "vcc-supply-1p8")) { > - vreg->min_uV = UFS_VREG_VCC_1P8_MIN_UV; > - vreg->max_uV = UFS_VREG_VCC_1P8_MAX_UV; > - } else { > - vreg->min_uV = UFS_VREG_VCC_MIN_UV; > - vreg->max_uV = UFS_VREG_VCC_MAX_UV; > - } > - } else if (!strcmp(name, "vccq")) { > - vreg->min_uV = UFS_VREG_VCCQ_MIN_UV; > - vreg->max_uV = UFS_VREG_VCCQ_MAX_UV; > - } else if (!strcmp(name, "vccq2")) { > - vreg->min_uV = UFS_VREG_VCCQ2_MIN_UV; > - vreg->max_uV = UFS_VREG_VCCQ2_MAX_UV; > - } > - > - goto out; > - > out: > if (!ret) > *out_vreg = vreg;
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