Since it is pretty common for only some of the CBUS lines to be valid as GPIO lines, let's report such validity to the rest of the kernel. Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> --- drivers/usb/serial/ftdi_sio.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c index e0f4c3d9649c..13e575f16bcd 100644 --- a/drivers/usb/serial/ftdi_sio.c +++ b/drivers/usb/serial/ftdi_sio.c @@ -2002,6 +2002,19 @@ static int ftdi_gpio_direction_output(struct gpio_chip *gc, unsigned int gpio, return result; } +static int ftdi_gpio_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, + unsigned int ngpios) +{ + struct usb_serial_port *port = gpiochip_get_data(gc); + struct ftdi_private *priv = usb_get_serial_port_data(port); + unsigned long map = priv->gpio_altfunc; + + bitmap_complement(valid_mask, &map, ngpios); + + return 0; +} + static int ftdi_read_eeprom(struct usb_serial *serial, void *dst, u16 addr, u16 nbytes) { @@ -2173,6 +2186,7 @@ static int ftdi_gpio_init(struct usb_serial_port *port) priv->gc.get_direction = ftdi_gpio_direction_get; priv->gc.direction_input = ftdi_gpio_direction_input; priv->gc.direction_output = ftdi_gpio_direction_output; + priv->gc.init_valid_mask = ftdi_gpio_init_valid_mask; priv->gc.get = ftdi_gpio_get; priv->gc.set = ftdi_gpio_set; priv->gc.get_multiple = ftdi_gpio_get_multiple; -- 2.28.0