]>
git.ipfire.org Git - people/ms/u-boot.git/blob - board/LaCie/common/cpld-gpio-bus.c
9b24dc535c04797a260a8604a24733ee62d81a44
2 * cpld-gpio-bus.c: provides support for the CPLD GPIO bus found on some LaCie
3 * boards (as the 2Big/5Big Network v2 and the 2Big NAS). This parallel GPIO
4 * bus exposes two registers (address and data). Each of this register is made
5 * up of several dedicated GPIOs. An extra GPIO is used to notify the CPLD that
6 * the registers have been updated.
8 * Mostly this bus is used to configure the LEDs on LaCie boards.
10 * Copyright (C) 2013 Simon Guinot <simon.guinot@sequanux.org>
12 * SPDX-License-Identifier: GPL-2.0+
15 #include <asm/arch/gpio.h>
16 #include "cpld-gpio-bus.h"
18 static void cpld_gpio_bus_set_addr(struct cpld_gpio_bus
*bus
, unsigned addr
)
22 for (pin
= 0; pin
< bus
->num_addr
; pin
++)
23 kw_gpio_set_value(bus
->addr
[pin
], (addr
>> pin
) & 1);
26 static void cpld_gpio_bus_set_data(struct cpld_gpio_bus
*bus
, unsigned data
)
30 for (pin
= 0; pin
< bus
->num_data
; pin
++)
31 kw_gpio_set_value(bus
->data
[pin
], (data
>> pin
) & 1);
34 static void cpld_gpio_bus_enable_select(struct cpld_gpio_bus
*bus
)
36 /* The transfer is enabled on the raising edge. */
37 kw_gpio_set_value(bus
->enable
, 0);
38 kw_gpio_set_value(bus
->enable
, 1);
41 void cpld_gpio_bus_write(struct cpld_gpio_bus
*bus
,
42 unsigned addr
, unsigned value
)
44 cpld_gpio_bus_set_addr(bus
, addr
);
45 cpld_gpio_bus_set_data(bus
, value
);
46 cpld_gpio_bus_enable_select(bus
);