This patch adds support for the GPIO extension bus found on some LaCie boards (as the 2Big/5Big Network v2 and the 2Big NAS). This bus allows to configure the devices (mostly the LEDs) connected to a CPLD via two GPIO-based registers (address and data).
Signed-off-by: Simon Guinot simon.guinot@sequanux.org --- board/LaCie/common/gpio-ext.c | 47 +++++++++++++++++++++++++++++++++++++++++ board/LaCie/common/gpio-ext.h | 24 +++++++++++++++++++++ 2 files changed, 71 insertions(+) create mode 100644 board/LaCie/common/gpio-ext.c create mode 100644 board/LaCie/common/gpio-ext.h
diff --git a/board/LaCie/common/gpio-ext.c b/board/LaCie/common/gpio-ext.c new file mode 100644 index 0000000..1e1b7ff --- /dev/null +++ b/board/LaCie/common/gpio-ext.c @@ -0,0 +1,47 @@ +/* + * gpio-ext.c: provides support for the GPIO extension bus found on some + * LaCie boards (as the 2Big/5Big Network v2 and the 2Big NAS). This bus + * allows to configure the devices (mostly the LEDs) connected to a CPLD + * via two GPIO-based registers (address and data). + * + * Copyright (C) 2013 Simon Guinot simon.guinot@sequanux.org + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + */ + +#include <asm/arch/gpio.h> +#include "gpio-ext.h" + +static void gpio_ext_set_addr(struct gpio_ext *gpio_ext, unsigned addr) +{ + int pin; + + for (pin = 0; pin < gpio_ext->num_addr; pin++) + kw_gpio_set_value(gpio_ext->addr[pin], (addr >> pin) & 1); +} + +static void gpio_ext_set_data(struct gpio_ext *gpio_ext, unsigned data) +{ + int pin; + + for (pin = 0; pin < gpio_ext->num_data; pin++) + kw_gpio_set_value(gpio_ext->data[pin], (data >> pin) & 1); +} + +static void gpio_ext_enable_select(struct gpio_ext *gpio_ext) +{ + /* The transfer is enabled on the raising edge. */ + kw_gpio_set_value(gpio_ext->enable, 0); + kw_gpio_set_value(gpio_ext->enable, 1); +} + +void gpio_ext_set_value(struct gpio_ext *gpio_ext, + unsigned addr, unsigned value) +{ + gpio_ext_set_addr(gpio_ext, addr); + gpio_ext_set_data(gpio_ext, value); + gpio_ext_enable_select(gpio_ext); +} diff --git a/board/LaCie/common/gpio-ext.h b/board/LaCie/common/gpio-ext.h new file mode 100644 index 0000000..09fa271 --- /dev/null +++ b/board/LaCie/common/gpio-ext.h @@ -0,0 +1,24 @@ +/* + * Copyright (C) 2013 Simon Guinot simon.guinot@sequanux.org + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + */ + +#ifndef _LACIE_GPIO_EXT_H +#define _LACIE_GPIO_EXT_H + +struct gpio_ext { + unsigned *addr; + unsigned num_addr; + unsigned *data; + unsigned num_data; + unsigned enable; +}; + +void gpio_ext_set_value(struct gpio_ext *gpio_ext, + unsigned addr, unsigned value); + +#endif /* _LACIE_GPIO_EXT_H */