[PATCH] pinctrl: rockchip: Enhance support for IRQ_TYPE_EDGE_BOTH

[PATCH] pinctrl: rockchip: Enhance support for IRQ_TYPE_EDGE_BOTH

[João H. Spies]

Switching between falling/rising edges for IRQ_TYPE_EDGE_BOTH on pins that
require debounce can cause the device to lose events due to a desync
between pin state and irq type.

This problem is resolved by switching between IRQ_TYPE_LEVEL_LOW and
IRQ_TYPE_LEVEL_HIGH instead.

Fixes: 936ee26 ("gpio/rockchip: add driver for rockchip gpio")
Signed-off-by: João H. Spies <jhlspies@gmail.com>
---
 drivers/gpio/gpio-rockchip.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c
index 099e358d2491..48b948723077 100644
--- a/drivers/gpio/gpio-rockchip.c
+++ b/drivers/gpio/gpio-rockchip.c
@@ -417,11 +417,11 @@ static int rockchip_irq_set_type(struct irq_data *d, unsigned int type)
 			goto out;
 		} else {
 			bank->toggle_edge_mode |= mask;
-			level |= mask;
+			level &= ~mask;
 
 			/*
 			 * Determine gpio state. If 1 next interrupt should be
-			 * falling otherwise rising.
+			 * low otherwise high.
 			 */
 			data = readl(bank->reg_base + bank->gpio_regs->ext_port);
 			if (data & mask)
-- 
2.30.2

Re: [PATCH] pinctrl: rockchip: Enhance support for IRQ_TYPE_EDGE_BOTH

[Linus Walleij]

On Mon, Aug 8, 2022 at 4:53 AM João H. Spies <jhlspies@gmail.com> wrote:

> Switching between falling/rising edges for IRQ_TYPE_EDGE_BOTH on pins that
> require debounce can cause the device to lose events due to a desync
> between pin state and irq type.
>
> This problem is resolved by switching between IRQ_TYPE_LEVEL_LOW and
> IRQ_TYPE_LEVEL_HIGH instead.
>
> Fixes: 936ee26 ("gpio/rockchip: add driver for rockchip gpio")
> Signed-off-by: João H. Spies <jhlspies@gmail.com>

No reaction from maintainers so I'm just gonna assume this fix is
correct and applied for fixes.

Yours,
Linus Walleij

Re: [PATCH] pinctrl: rockchip: Enhance support for IRQ_TYPE_EDGE_BOTH

[Heiko Stübner]

Am Montag, 22. August 2022, 11:03:08 CEST schrieb Linus Walleij:
> On Mon, Aug 8, 2022 at 4:53 AM João H. Spies <jhlspies@gmail.com> wrote:
> 
> > Switching between falling/rising edges for IRQ_TYPE_EDGE_BOTH on pins that
> > require debounce can cause the device to lose events due to a desync
> > between pin state and irq type.
> >
> > This problem is resolved by switching between IRQ_TYPE_LEVEL_LOW and
> > IRQ_TYPE_LEVEL_HIGH instead.
> >
> > Fixes: 936ee26 ("gpio/rockchip: add driver for rockchip gpio")
> > Signed-off-by: João H. Spies <jhlspies@gmail.com>
> 
> No reaction from maintainers so I'm just gonna assume this fix is
> correct and applied for fixes.

This plays with behavioral peculiarities of the gpio controller
(using the level setting to hopefully prevent missing edge irqs),
so doesn't follow

So I guess it really is more of a wait-and-see. And I guess as João
seems to have experienced that issue, that will hopefully work
for others too.

Heiko