From 40d7d6b3abc74d77fc7bba4977226ff4aa7721e9 Mon Sep 17 00:00:00 2001 From: "Bao D. Nguyen" Date: Mon, 11 Sep 2017 12:08:26 -0700 Subject: [PATCH] scsi: ufs: Read device tree to find UFS's Vcc voltage level This change allows selecting the UFS Vcc voltage level by setting the UFS's entry vcc-voltage-level in the device tree. If UFS's Vcc voltage level setting is not found in the device tree, use default values provided by the driver. Change-Id: Ifc6856d63b672ed6b178f45fd5f139cb2fa56f15 Signed-off-by: Bao D. Nguyen --- drivers/scsi/ufs/ufshcd-pltfrm.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c index 5e48e6029257..c91023e57194 100644 --- a/drivers/scsi/ufs/ufshcd-pltfrm.c +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c @@ -129,10 +129,11 @@ out: static int ufshcd_populate_vreg(struct device *dev, const char *name, struct ufs_vreg **out_vreg) { - int ret = 0; + int len, ret = 0; char prop_name[MAX_PROP_SIZE]; struct ufs_vreg *vreg = NULL; struct device_node *np = dev->of_node; + const __be32 *prop; if (!np) { dev_err(dev, "%s: non DT initialization\n", __func__); @@ -162,8 +163,16 @@ static int ufshcd_populate_vreg(struct device *dev, const char *name, 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; + prop = of_get_property(np, "vcc-voltage-level", &len); + if (!prop || (len != (2 * sizeof(__be32)))) { + dev_warn(dev, "%s vcc-voltage-level property.\n", + prop ? "invalid format" : "no"); + vreg->min_uV = UFS_VREG_VCC_MIN_UV; + vreg->max_uV = UFS_VREG_VCC_MAX_UV; + } else { + vreg->min_uV = be32_to_cpup(&prop[0]); + vreg->max_uV = be32_to_cpup(&prop[1]); + } } } else if (!strcmp(name, "vccq")) { vreg->min_uV = UFS_VREG_VCCQ_MIN_UV;