linux-kernel - [PATCH 1/2] gpio: max77620: Fixup debounce delays

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Date:   Fri,  8 Nov 2019 17:07:46 +0100
From:   Thierry Reding <thierry.reding@...il.com>
To:     Linus Walleij <linus.walleij@...aro.org>,
        Bartosz Golaszewski <bgolaszewski@...libre.com>
Cc:     Pavel Machek <pavel@...x.de>, linux-gpio@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH 1/2] gpio: max77620: Fixup debounce delays

From: Thierry Reding <treding@...dia.com>

When converting milliseconds to microseconds in commit fffa6af94894
("gpio: max77620: Use correct unit for debounce times") some ~1 ms gaps
were introduced between the various ranges supported by the controller.
Fix this by changing the start of each range to the value immediately
following the end of the previous range. This way a debounce time of,
say 8250 us will translate into 16 ms instead of returning an -EINVAL
error.

Typically the debounce delay is only ever set through device tree and
specified in milliseconds, so we can never really hit this issue because
debounce times are always a multiple of 1000 us.

The only notable exception for this is drivers/mmc/host/mmc-spi.c where
the CD GPIO is requested, which passes a 1 us debounce time. According
to a comment preceeding that code this should actually be 1 ms (i.e.
1000 us).

Reported-by: Pavel Machek <pavel@...x.de>
Signed-off-by: Thierry Reding <treding@...dia.com>
---
 drivers/gpio/gpio-max77620.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpio-max77620.c b/drivers/gpio/gpio-max77620.c
index c5b64a4ac172..313bd02dd893 100644
--- a/drivers/gpio/gpio-max77620.c
+++ b/drivers/gpio/gpio-max77620.c
@@ -198,13 +198,13 @@ static int max77620_gpio_set_debounce(struct max77620_gpio *mgpio,
 	case 0:
 		val = MAX77620_CNFG_GPIO_DBNC_None;
 		break;
-	case 1000 ... 8000:
+	case 1 ... 8000:
 		val = MAX77620_CNFG_GPIO_DBNC_8ms;
 		break;
-	case 9000 ... 16000:
+	case 8001 ... 16000:
 		val = MAX77620_CNFG_GPIO_DBNC_16ms;
 		break;
-	case 17000 ... 32000:
+	case 16001 ... 32000:
 		val = MAX77620_CNFG_GPIO_DBNC_32ms;
 		break;
 	default:
-- 
2.23.0