From 0debed5b117d11e33cba52870c4dcb64f5911891 Mon Sep 17 00:00:00 2001 From: ChiYuan Huang Date: Wed, 14 Dec 2022 09:37:11 +0800 Subject: regulator: core: Fix resolve supply lookup issue From Marek's log, the previous change modify the parent of rdev. https://lore.kernel.org/all/58b92e75-f373-dae7-7031-8abd465bb874@samsung.com/ In 'regulator_resolve_supply', it uses the parent DT node of rdev as the DT-lookup starting node. But the parent DT node may not exist. This will cause the NULL supply issue. This patch modify the parent of rdev back to the device that provides from 'regulator_config' in 'regulator_register'. Fixes: 8f3cbcd6b440 ("regulator: core: Use different devices for resource allocation and DT lookup") Reported-by: Marek Szyprowski Tested-by: Marek Szyprowski Signed-off-by: ChiYuan Huang Link: https://lore.kernel.org/r/1670981831-12583-1-git-send-email-u0084500@gmail.com Signed-off-by: Mark Brown --- drivers/regulator/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index c84e8d78dc7e..35a7785c53f6 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -5539,7 +5539,7 @@ regulator_register(struct device *dev, /* register with sysfs */ rdev->dev.class = ®ulator_class; - rdev->dev.parent = dev; + rdev->dev.parent = config->dev; dev_set_name(&rdev->dev, "regulator.%lu", (unsigned long) atomic_inc_return(®ulator_no)); dev_set_drvdata(&rdev->dev, rdev); -- cgit v1.2.3 From cb3543cff90a4448ed560ac86c98033ad5fecda9 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Thu, 15 Dec 2022 11:46:46 +0100 Subject: regulator: core: fix deadlock on regulator enable When updating the operating mode as part of regulator enable, the caller has already locked the regulator tree and drms_uA_update() must not try to do the same in order not to trigger a deadlock. The lock inversion is reported by lockdep as: ====================================================== WARNING: possible circular locking dependency detected 6.1.0-next-20221215 #142 Not tainted ------------------------------------------------------ udevd/154 is trying to acquire lock: ffffc11f123d7e50 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x280 but task is already holding lock: ffff80000e4c36e8 (regulator_ww_class_acquire){+.+.}-{0:0}, at: regulator_enable+0x34/0x80 which lock already depends on the new lock. ... Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(regulator_ww_class_acquire); lock(regulator_list_mutex); lock(regulator_ww_class_acquire); lock(regulator_list_mutex); *** DEADLOCK *** just before probe of a Qualcomm UFS controller (occasionally) deadlocks when enabling one of its regulators. Fixes: 9243a195be7a ("regulator: core: Change voltage setting path") Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking") Cc: stable@vger.kernel.org # 5.0 Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20221215104646.19818-1-johan+linaro@kernel.org Signed-off-by: Mark Brown --- drivers/regulator/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c index 35a7785c53f6..c661be129818 100644 --- a/drivers/regulator/core.c +++ b/drivers/regulator/core.c @@ -1002,7 +1002,7 @@ static int drms_uA_update(struct regulator_dev *rdev) /* get input voltage */ input_uV = 0; if (rdev->supply) - input_uV = regulator_get_voltage(rdev->supply); + input_uV = regulator_get_voltage_rdev(rdev->supply->rdev); if (input_uV <= 0) input_uV = rdev->constraints->input_uV; -- cgit v1.2.3