[PATCH 3/4] bcm2835-gpio-exp: Driver for GPIO expander via mailbox service
Linus Walleij
linus.walleij at linaro.org
Wed Jan 3 02:08:15 PST 2018
On Tue, Jan 2, 2018 at 2:19 PM, Baruch Siach <baruch at tkos.co.il> wrote:
> +config GPIO_BCM_EXP
> + bool "Broadcom Exp GPIO"
> + depends on OF_GPIO && RASPBERRYPI_FIRMWARE && (ARCH_BCM2835 || COMPILE_TEST)
> + help
> + Turn on GPIO support for Broadcom chips using the firmware mailbox
> + to communicate with VideoCore on BCM283x chips.
Should this be
default RASPBERRYPI_FIRMWARE
So it is always available if the firmware interface is there?
> +#include <linux/err.h>
> +#include <linux/gpio.h>
Just use
#include <linux/driver.h>
> +#define MODULE_NAME "brcmexp-gpio"
> +#define NUM_GPIO 8
> +
> +struct brcmexp_gpio {
> + struct gpio_chip gc;
> + struct device *dev;
> + struct rpi_firmware *fw;
> +};
> +
> +struct gpio_set_config {
> + u32 gpio, direction, polarity, term_en, term_pull_up, state;
> +};
> +
> +struct gpio_get_config {
> + u32 gpio, direction, polarity, term_en, term_pull_up;
> +};
Seems to support some pin control stuff, hm?
The pull ups seems unused though so OK.
Yours,
Linus Walleij
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