From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stanley Chu Subject: [PATCH RESEND v3 5/5] scsi: ufs: Remove "-fixed-regulator" device tree property Date: Wed, 27 Mar 2019 17:58:27 +0800 Message-ID: <1553680707-28579-6-git-send-email-stanley.chu@mediatek.com> References: <1553680707-28579-1-git-send-email-stanley.chu@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1553680707-28579-1-git-send-email-stanley.chu-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+glpam-linux-mediatek=m.gmane.org-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org To: linux-scsi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, martin.petersen-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, avri.altman-Sjgp3cTcYWE@public.gmane.org, alim.akhtar-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org, pedrom.sousa-HKixBCOQz3hWk0Htik3J/w@public.gmane.org Cc: marc.w.gonzalez-GANU6spQydw@public.gmane.org, chun-hung.wu-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, kuohong.wang-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, linux-mediatek-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, peter.wang-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org, matthias.bgg-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Stanley Chu List-Id: linux-mediatek@lists.infradead.org "-fixed-regulator" device tree property can be safely removed because below things are fixed or resolved, 1. "-max-microamp" becomes optional property: Undefined "-max-microamp" will not cause initialization fail if "-fixed-regulator" is not defined. 2. Current switching operation (by regulator_set_load) now has rules: Regulators will have undefined current limit if "-fixed-regulator" is not defined. But this is safe because only regulator which has configured current limit from "-max-microamp" property is allowed to change its load. Although "-fixed-regulator" is not used in any dt-bindings in tree, this patch is still safe for regulators already defined "-fixed-regulator". To be more clear, if a regulator defined "-fixed-regulator" before, the behavior difference after this patch is, 1. "-max-microamp": If a regulator defined "-fixed-regulator", it is not necessary to define "-max-microamp" property in device tree and it is expected to have an undefined current limit, i.e., "max_uA" field is zero in struct ufs_vreg. This is exactly the same as patched. 2. "vcc-supply-1p8" or volatge range settings: * For vcc, vccq or vccq2, these three regulators shall not define "-fixed-regulator" because defining it will lead to undefined voltage range and thus voltage switching will be unexpected. * For other regulators with undefined voltage range, voltage range will be still undefined after patched. Therefore this patch is safe for all existed regulators with "-fixed-regulator" property already defined. Signed-off-by: Stanley Chu --- drivers/scsi/ufs/ufshcd-pltfrm.c | 5 ----- 1 file changed, 5 deletions(-) diff --git a/drivers/scsi/ufs/ufshcd-pltfrm.c b/drivers/scsi/ufs/ufshcd-pltfrm.c index 2420e6962219..7b404df965b2 100644 --- a/drivers/scsi/ufs/ufshcd-pltfrm.c +++ b/drivers/scsi/ufs/ufshcd-pltfrm.c @@ -151,11 +151,6 @@ static int ufshcd_populate_vreg(struct device *dev, const char *name, vreg->name = kstrdup(name, GFP_KERNEL); - /* if fixed regulator no need further initialization */ - snprintf(prop_name, MAX_PROP_SIZE, "%s-fixed-regulator", name); - if (of_property_read_bool(np, prop_name)) - goto out; - snprintf(prop_name, MAX_PROP_SIZE, "%s-max-microamp", name); if (of_property_read_u32(np, prop_name, &vreg->max_uA)) { dev_info(dev, "%s: unable to find %s\n", __func__, prop_name); -- 2.18.0