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Input: adp5588-keys - cache GPIO state before registering the gpiochip

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So as not to clobber any pre-programmed GPIO state in the execution
of its gpiochip ops, the driver caches things during probe time.
However, since those ops can be called both during and immediately after
the call to devm_gpiochip_add_data(), it is imperative that things are
cached before that. That's not the case right now, so reorder the two
steps to prevent any clobbering.

In the concrete example which motivated this change, a bootloader was
preconfiguring an important GPIO output to HIGH before booting the
kernel. Linux would then inadvertently set that output to LOW while
configuring a GPIO hog on a discrete GPIO line within the same 8-bit
bank (because the cached value was 0=LOW).

Fixes: ba9f507a1b ("Input: adp5588-keys - export unused GPIO pins")
Signed-off-by: Alvin Šipraga <alvin.sipraga@analog.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://patch.msgid.link/20260818-adp5588-gpio-cache-v1-1-650a2674fc0d@analog.com
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
This commit is contained in:
Alvin Šipraga 2026-08-18 18:00:02 +02:00 committed by Dmitry Torokhov
parent b4d85f863e
commit 21efadc622
1 changed files with 6 additions and 6 deletions
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12
drivers/input/keyboard/adp5588-keys.c
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@ -446,12 +446,6 @@ static int adp5588_gpio_add(struct adp5588_kpad *kpad)
mutex_init(&kpad->gpio_lock);
error = devm_gpiochip_add_data(dev, &kpad->gc, kpad);
if (error) {
dev_err(dev, "gpiochip_add failed: %d\n", error);
return error;
}
for (i = 0; i <= ADP5588_BANK(ADP5588_MAXGPIO); i++) {
kpad->dat_out[i] = adp5588_read(kpad->client,
GPIO_DAT_OUT1 + i);
@ -459,6 +453,12 @@ static int adp5588_gpio_add(struct adp5588_kpad *kpad)
kpad->pull_dis[i] = adp5588_read(kpad->client, GPIO_PULL1 + i);
}
error = devm_gpiochip_add_data(dev, &kpad->gc, kpad);
if (error) {
dev_err(dev, "gpiochip_add failed: %d\n", error);
return error;
}
return 0;
}