Messages in this thread | | | Date | Wed, 23 Jul 2014 17:03:14 +0100 | From | One Thousand Gnomes <> | Subject | Re: [PATCH v2] usb:serial:pl2303: add GPIOs interface on PL2303 |
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> --- a/drivers/usb/serial/pl2303.c > +++ b/drivers/usb/serial/pl2303.c > @@ -28,6 +28,9 @@ > #include <linux/usb.h> > #include <linux/usb/serial.h> > #include <asm/unaligned.h> > +#ifdef CONFIG_USB_SERIAL_PL2303_GPIO > +#include <linux/gpio.h> > +#endif > #include "pl2303.h"
Just include the file anyway it does no harm
> > > @@ -143,9 +146,27 @@ struct pl2303_type_data { > unsigned long quirks; > }; > > +#ifdef CONFIG_USB_SERIAL_PL2303_GPIO > +struct pl2303_gpio { > + /* > + * 0..3: unknown (zero) > + * 4: gp0 output enable (1: gp0 pin is output, 0: gp0 pin is input) > + * 5: gp1 output enable (1: gp1 pin is output, 0: gp1 pin is input) > + * 6: gp0 pin value > + * 7: gp1 pin value > + */ > + u8 index; > + struct usb_serial *serial; > + struct gpio_chip gpio_chip; > +}; > +#endif
Declaring the struct anyway does no harm
> struct pl2303_serial_private *spriv = usb_get_serial_data(serial); > > +#ifdef CONFIG_USB_SERIAL_PL2303_GPIO > + if (spriv && spriv->gpio) {
Can spriv ever be NULL - how would that occur?
> + if (gpiochip_remove(&spriv->gpio->gpio_chip)) > + dev_err(&serial->interface->dev, "unable to remove gpio_chip?\n"); > + kfree(spriv->gpio); > + } > +#endif > kfree(spriv);
Only other question I have - if I have multiple PL2303HX adapters how will I work out which GPIO lines belong to which /dev/ttyUSB* interface ?
Do we need a way to actually ask the serial port for its GPIO range ?
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