4.16-stable review patch. If anyone has any objections, please let me know.
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From: Richard Fitzgerald rf@opensource.cirrus.com
[ Upstream commit b89405b6102fcc3746f43697b826028caa94c823 ]
When dt_to_map_one_config() is called with a pinctrl_dev passed in, it should only be using this if the node being looked up is a hog. The code was always using the passed pinctrl_dev without checking whether the dt node referred to it.
A pin controller can have pinctrl-n dependencies on other pin controllers in these cases:
- the pin controller hardware is external, for example I2C, so needs other pin controller(s) to be setup to communicate with the hardware device.
- it is a child of a composite MFD so its of_node is shared with the parent MFD and other children of that MFD. Any part of that MFD could have dependencies on other pin controllers.
Because of this, dt_to_map_one_config() can't assume that if it has a pinctrl_dev passed in then the node it looks up must be a hog. It could be a reference to some other pin controller.
Signed-off-by: Richard Fitzgerald rf@opensource.cirrus.com Signed-off-by: Linus Walleij linus.walleij@linaro.org Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/pinctrl/devicetree.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/drivers/pinctrl/devicetree.c +++ b/drivers/pinctrl/devicetree.c @@ -122,8 +122,10 @@ static int dt_to_map_one_config(struct p /* OK let's just assume this will appear later then */ return -EPROBE_DEFER; } - if (!pctldev) - pctldev = get_pinctrl_dev_from_of_node(np_pctldev); + /* If we're creating a hog we can use the passed pctldev */ + if (pctldev && (np_pctldev == p->dev->of_node)) + break; + pctldev = get_pinctrl_dev_from_of_node(np_pctldev); if (pctldev) break; /* Do not defer probing of hogs (circular loop) */