From fc7a90686777e7d2da7a08cf0202c21f3b96febb Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Thu, 1 Jun 2017 14:18:26 +0200 Subject: [PATCH] gpio: mvebu: fix gpio bank registration when pwm is used If more than one gpio bank has the "pwm" property, only one will be registered successfully, all the others will fail with: mvebu-gpio: probe of f1018140.gpio failed with error -17 That's because in alloc_pwms(), the chip->base (aka "int pwm"), was not set (thus, ==0) ; and 0 is a meaningful start value in alloc_pwm(). What was intended is mvpwm->chip->base = -1. Like that, the numbering will be done auto-magically Moreover, as the region might be already occupied by another pwm, we shouldn't force: mvpwm->chip->base = 0 nor mvpwm->chip->base = id * MVEBU_MAX_GPIO_PER_BANK; Tested on clearfog-pro (Marvell 88F6828) Fixes: 757642f9a584 ("gpio: mvebu: Add limited PWM support") Signed-off-by: Richard Genoud Reviewed-by: Gregory CLEMENT Signed-off-by: Linus Walleij --- drivers/gpio/gpio-mvebu.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/gpio/gpio-mvebu.c b/drivers/gpio/gpio-mvebu.c index cdef2c78cb3b..5104b6398139 100644 --- a/drivers/gpio/gpio-mvebu.c +++ b/drivers/gpio/gpio-mvebu.c @@ -768,6 +768,13 @@ static int mvebu_pwm_probe(struct platform_device *pdev, mvpwm->chip.dev = dev; mvpwm->chip.ops = &mvebu_pwm_ops; mvpwm->chip.npwm = mvchip->chip.ngpio; + /* + * There may already be some PWM allocated, so we can't force + * mvpwm->chip.base to a fixed point like mvchip->chip.base. + * So, we let pwmchip_add() do the numbering and take the next free + * region. + */ + mvpwm->chip.base = -1; spin_lock_init(&mvpwm->lock);