Hi Francesco,
On 7/13/2026 2:07 AM, Francesco Dolcini wrote:
Hello Judith,
On Fri, Jul 10, 2026 at 06:04:09PM -0500, Judith Mendez wrote:
Some board designs have slow RC circuits on GPIO outputs controlled by
PCA953X I2C expanders. On some board designs, pin voltage transitions
can take significant time after I2C write command completes.
Add an optional "gpio-settle-delay-ms" device tree property for the
pca953x driver to add a delay after I2C write if specified, allowing to
compensate for slow RC circuits.
Signed-off-by: Judith Mendez <[email protected]>
---
drivers/gpio/pca953x_gpio.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/gpio/pca953x_gpio.c b/drivers/gpio/pca953x_gpio.c
index 965a5fcf30b..54b957069c9 100644
--- a/drivers/gpio/pca953x_gpio.c
+++ b/drivers/gpio/pca953x_gpio.c
@@ -333,6 +339,8 @@ static int pca953x_probe(struct udevice *dev)
info->bank_count = DIV_ROUND_UP(info->gpio_count, BANK_SZ);
+ info->settle_delay_ms = dev_read_u32_default(dev, "gpio-settle-delay-ms", 0);
Is this property supported also in Linux and defined in the Linux
binding? I do not think we should have U-Boot specific DT properties.
yea you are right. I guess we can use gpio-delay instead.
~ Judith
