[PATCH AUTOSEL 4.14 142/150] pinctrl: qcom: spmi-gpio: fix gpio-hog related boot issues
From: Sasha Levin <sashal@kernel.org>
Date: 2019-11-16 15:51:09
Also in:
linux-arm-msm, lkml, stable
Subsystem:
arm/qualcomm mailing list, pin control subsystem, pin controller - qualcomm, the rest · Maintainers:
Linus Walleij, Bjorn Andersson, Linus Torvalds
From: Brian Masney <redacted>
[ Upstream commit 149a96047237574b756d872007c006acd0cc6687 ]
When attempting to setup up a gpio hog, device probing would repeatedly
fail with -EPROBE_DEFERED errors. It was caused by a circular dependency
between the gpio and pinctrl frameworks. If the gpio-ranges property is
present in device tree, then the gpio framework will handle the gpio pin
registration and eliminate the circular dependency.
See Christian Lamparter's commit a86caa9ba5d7 ("pinctrl: msm: fix
gpio-hog related boot issues") for a detailed commit message that
explains the issue in much more detail. The code comment in this commit
came from Christian's commit.
Signed-off-by: Brian Masney <redacted>
Signed-off-by: Linus Walleij <redacted>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/pinctrl/qcom/pinctrl-spmi-gpio.c | 21 +++++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)
diff --git a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
index 22aaf4375fac0..0f0049dfaa3a1 100644
--- a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
+++ b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c@@ -1023,10 +1023,23 @@ static int pmic_gpio_probe(struct platform_device *pdev) return ret; } - ret = gpiochip_add_pin_range(&state->chip, dev_name(dev), 0, 0, npins); - if (ret) { - dev_err(dev, "failed to add pin range\n"); - goto err_range; + /* + * For DeviceTree-supported systems, the gpio core checks the + * pinctrl's device node for the "gpio-ranges" property. + * If it is present, it takes care of adding the pin ranges + * for the driver. In this case the driver can skip ahead. + * + * In order to remain compatible with older, existing DeviceTree + * files which don't set the "gpio-ranges" property or systems that + * utilize ACPI the driver has to call gpiochip_add_pin_range(). + */ + if (!of_property_read_bool(dev->of_node, "gpio-ranges")) { + ret = gpiochip_add_pin_range(&state->chip, dev_name(dev), 0, 0, + npins); + if (ret) { + dev_err(dev, "failed to add pin range\n"); + goto err_range; + } } return 0;
--
2.20.1