On Thu, Jun 10, 2021 at 03:28:44PM +0200, Johan Hovold wrote: > From: Pho Tran <pho.tran@xxxxxxxxxx> > > Similar to some other CP210x device types, CP2108 has a number of GPIO > pins that can be exposed through gpiolib. > > CP2108 has four serial interfaces but only one set of GPIO pins, which > is modelled as a single gpio chip and registered as a child of the first > interface. > > CP2108 has 16 GPIOs so the width of the state variables needs to be > extended to 16 bits and this is also reflected in the control requests. > > Like CP2104, CP2108 have GPIO pins with configurable alternate > functions and pins unavailable for GPIO use are determined and reported > to gpiolib at probe. > > Signed-off-by: Pho Tran <pho.tran@xxxxxxxxxx> > Co-developed-by: Tung Pham <tung.pham@xxxxxxxxxx> > Signed-off-by: Tung Pham <tung.pham@xxxxxxxxxx> > [ johan: rewrite gpio get() and set(); misc cleanups; amend commit > message ] > Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> > --- > > Tested using CP2108 and CP2102N. > > Changes in v13 > - rewrite cp210x_gpio_get() using a shared 16 bit mask and > le16_to_cpus() > - rewrite cp210x_gpio_set() using shared 16-bit mask and state > variables > - drop pointless no-op shift and mask operations during initialisation > - reorder defines > - reword some comments > - fix some style issues > - amend commit message > > v12 can be found here: > - https://lore.kernel.org/r/20210426091244.19994-1-tupham@xxxxxxxxxx > > > drivers/usb/serial/cp210x.c | 189 ++++++++++++++++++++++++++++++++---- > 1 file changed, 170 insertions(+), 19 deletions(-) > @@ -1414,52 +1468,84 @@ static int cp210x_gpio_get(struct gpio_chip *gc, unsigned int gpio) > { > struct usb_serial *serial = gpiochip_get_data(gc); > struct cp210x_serial_private *priv = usb_get_serial_data(serial); > - u8 req_type = REQTYPE_DEVICE_TO_HOST; > + u8 req_type; > + u16 mask; > int result; > - u8 buf; > - > - if (priv->partnum == CP210X_PARTNUM_CP2105) > - req_type = REQTYPE_INTERFACE_TO_HOST; > + int len; > > result = usb_autopm_get_interface(serial->interface); > if (result) > return result; > > - result = cp210x_read_vendor_block(serial, req_type, > - CP210X_READ_LATCH, &buf, sizeof(buf)); > + switch (priv->partnum) { > + case CP210X_PARTNUM_CP2105: > + req_type = REQTYPE_INTERFACE_TO_HOST; > + len = 1; > + break; > + case CP210X_PARTNUM_CP2108: > + req_type = REQTYPE_INTERFACE_TO_HOST; > + len = 2; > + break; > + default: > + req_type = REQTYPE_DEVICE_TO_HOST; > + len = 1; > + break; > + } > + > + mask = 0; > + result = cp210x_read_vendor_block(serial, req_type, CP210X_READ_LATCH, > + &mask, len); > + > usb_autopm_put_interface(serial->interface); > + > if (result < 0) > return result; > > - return !!(buf & BIT(gpio)); > + le16_to_cpus((__le16 *)&mask); Now applied after removing the (__le16 *) cast here. > + > + return !!(mask & BIT(gpio)); > } Johan
