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authorBrian Masney <masneyb@onstation.org>2018-10-31 20:11:47 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-11-28 18:26:09 +0100
commit14d1265f7dc89047a0da98e8926ffd8c584b80ad (patch)
tree25b0d8e16994007b013c14a8dd29f100c58c2eed /drivers/pinctrl
parent4c5ce7ca90e00164f954d727215fc227addc467c (diff)
pinctrl: qcom: spmi-gpio: fix gpio-hog related boot issues
[ 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 <masneyb@onstation.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/pinctrl')
-rw-r--r--drivers/pinctrl/qcom/pinctrl-spmi-gpio.c21
1 files changed, 17 insertions, 4 deletions
diff --git a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
index 4ea810cafaac..913b2604d345 100644
--- a/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
+++ b/drivers/pinctrl/qcom/pinctrl-spmi-gpio.c
@@ -793,10 +793,23 @@ static int pmic_gpio_probe(struct platform_device *pdev)
goto err_chip;
}
- 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;