On Thu, May 18, 2017 at 5:59 PM, Jan Kiszka <jan.kis...@siemens.com> wrote: > On the SIMATIC, IOT2040 only a single pin is exportable as GPIO, the > rest is required to operate the UART. To allow modeling this case, > expand the platform device data structure to specify a (consecutive) pin > subset for exporting by the gpio-exar driver.
> + unsigned int first_gpio; Perhaps pin? Or shift? Because first_gpio a bit confusing with Linux side of GPIO. > - unsigned int bank = offset / 8; > - unsigned int addr; > + struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip); > + unsigned int bank, addr; > > + offset += exar_gpio->first_gpio; > + bank = offset / 8; Can't we instead do something like the following: struct exar_gpio_chip *exar_gpio = gpiochip_get_data(chip); unsigned int bank = (offset + exar_gpio->pin) / 8; unsigned int line = (offset + exar_gpio->pin) % 8; > + pdata.first_gpio = first_gpio; > + pdata.ngpio = ngpio; Still thinking about device properties ("ngpios" and something like "exar8250,gpio-start"). > + unsigned int first_gpio; > + unsigned int ngpio; u16 ? -- With Best Regards, Andy Shevchenko