diff options
Diffstat (limited to 'arch/blackfin/mach-bf548/gpio.c')
-rw-r--r-- | arch/blackfin/mach-bf548/gpio.c | 323 |
1 files changed, 323 insertions, 0 deletions
diff --git a/arch/blackfin/mach-bf548/gpio.c b/arch/blackfin/mach-bf548/gpio.c new file mode 100644 index 00000000000..0da5f0003b8 --- /dev/null +++ b/arch/blackfin/mach-bf548/gpio.c @@ -0,0 +1,323 @@ +/* + * File: arch/blackfin/mach-bf548/gpio.c + * Based on: + * Author: Michael Hennerich (hennerich@blackfin.uclinux.org) + * + * Created: + * Description: GPIO Abstraction Layer + * + * Modified: + * Copyright 2007 Analog Devices Inc. + * + * Bugs: Enter bugs at http://blackfin.uclinux.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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see the file COPYING, or write + * to the Free Software Foundation, Inc., + * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <linux/module.h> +#include <linux/err.h> +#include <asm/blackfin.h> +#include <asm/gpio.h> +#include <asm/portmux.h> +#include <linux/irq.h> + +static struct gpio_port_t *gpio_array[gpio_bank(MAX_BLACKFIN_GPIOS)] = { + (struct gpio_port_t *)PORTA_FER, + (struct gpio_port_t *)PORTB_FER, + (struct gpio_port_t *)PORTC_FER, + (struct gpio_port_t *)PORTD_FER, + (struct gpio_port_t *)PORTE_FER, + (struct gpio_port_t *)PORTF_FER, + (struct gpio_port_t *)PORTG_FER, + (struct gpio_port_t *)PORTH_FER, + (struct gpio_port_t *)PORTI_FER, + (struct gpio_port_t *)PORTJ_FER, +}; + +static unsigned short reserved_gpio_map[gpio_bank(MAX_BLACKFIN_GPIOS)]; +static unsigned short reserved_peri_map[gpio_bank(MAX_BLACKFIN_GPIOS)]; + +inline int check_gpio(unsigned short gpio) +{ + if (gpio == GPIO_PB15 || gpio == GPIO_PC14 || gpio == GPIO_PC15 + || gpio == GPIO_PH14 || gpio == GPIO_PH15 + || gpio == GPIO_PJ14 || gpio == GPIO_PJ15 + || gpio > MAX_BLACKFIN_GPIOS) + return -EINVAL; + return 0; +} + +inline void portmux_setup(unsigned short portno, unsigned short function) +{ + u32 pmux; + + pmux = gpio_array[gpio_bank(portno)]->port_mux; + + pmux &= ~(0x3 << (2 * gpio_sub_n(portno))); + pmux |= (function & 0x3) << (2 * gpio_sub_n(portno)); + + gpio_array[gpio_bank(portno)]->port_mux = pmux; + +} + +inline u16 get_portmux(unsigned short portno) +{ + u32 pmux; + + pmux = gpio_array[gpio_bank(portno)]->port_mux; + + return (pmux >> (2 * gpio_sub_n(portno)) & 0x3); + +} + +static void port_setup(unsigned short gpio, unsigned short usage) +{ + if (usage == GPIO_USAGE) { + if (gpio_array[gpio_bank(gpio)]->port_fer & gpio_bit(gpio)) + printk(KERN_WARNING + "bfin-gpio: Possible Conflict with Peripheral " + "usage and GPIO %d detected!\n", gpio); + gpio_array[gpio_bank(gpio)]->port_fer &= ~gpio_bit(gpio); + } else + gpio_array[gpio_bank(gpio)]->port_fer |= gpio_bit(gpio); + SSYNC(); +} + +static int __init bfin_gpio_init(void) +{ + printk(KERN_INFO "Blackfin GPIO Controller\n"); + + return 0; +} + +arch_initcall(bfin_gpio_init); + +int peripheral_request(unsigned short per, const char *label) +{ + unsigned long flags; + unsigned short ident = P_IDENT(per); + + if (!(per & P_DEFINED)) + return -ENODEV; + + if (check_gpio(ident) < 0) + return -EINVAL; + + local_irq_save(flags); + + if (unlikely(reserved_gpio_map[gpio_bank(ident)] & gpio_bit(ident))) { + printk(KERN_ERR + "%s: Peripheral %d is already reserved as GPIO!\n", + __FUNCTION__, per); + dump_stack(); + local_irq_restore(flags); + return -EBUSY; + } + + if (unlikely(reserved_peri_map[gpio_bank(ident)] & gpio_bit(ident))) { + + u16 funct = get_portmux(ident); + + if (!((per & P_MAYSHARE) && (funct == P_FUNCT2MUX(per)))) { + printk(KERN_ERR + "%s: Peripheral %d is already reserved!\n", + __FUNCTION__, per); + dump_stack(); + local_irq_restore(flags); + return -EBUSY; + } + } + + reserved_peri_map[gpio_bank(ident)] |= gpio_bit(ident); + + portmux_setup(ident, P_FUNCT2MUX(per)); + port_setup(ident, PERIPHERAL_USAGE); + + local_irq_restore(flags); + + return 0; +} +EXPORT_SYMBOL(peripheral_request); + +int peripheral_request_list(unsigned short per[], const char *label) +{ + + u16 cnt; + int ret; + + for (cnt = 0; per[cnt] != 0; cnt++) { + ret = peripheral_request(per[cnt], label); + if (ret < 0) + return ret; + } + + return 0; +} +EXPORT_SYMBOL(peripheral_request_list); + +void peripheral_free(unsigned short per) +{ + unsigned long flags; + unsigned short ident = P_IDENT(per); + + if (!(per & P_DEFINED)) + return; + + if (check_gpio(ident) < 0) + return; + + local_irq_save(flags); + + if (unlikely(!(reserved_peri_map[gpio_bank(ident)] & gpio_bit(ident)))) { + printk(KERN_ERR "bfin-gpio: Peripheral %d wasn't reserved!\n", per); + dump_stack(); + local_irq_restore(flags); + return; + } + + if (!(per & P_MAYSHARE)) { + port_setup(ident, GPIO_USAGE); + } + + reserved_peri_map[gpio_bank(ident)] &= ~gpio_bit(ident); + + local_irq_restore(flags); +} +EXPORT_SYMBOL(peripheral_free); + +void peripheral_free_list(unsigned short per[]) +{ + u16 cnt; + + for (cnt = 0; per[cnt] != 0; cnt++) { + peripheral_free(per[cnt]); + } + +} +EXPORT_SYMBOL(peripheral_free_list); + +/*********************************************************** +* +* FUNCTIONS: Blackfin GPIO Driver +* +* INPUTS/OUTPUTS: +* gpio - GPIO Number between 0 and MAX_BLACKFIN_GPIOS +* +* +* DESCRIPTION: Blackfin GPIO Driver API +* +* CAUTION: +************************************************************* +* MODIFICATION HISTORY : +**************************************************************/ + +int gpio_request(unsigned short gpio, const char *label) +{ + unsigned long flags; + + if (check_gpio(gpio) < 0) + return -EINVAL; + + local_irq_save(flags); + + if (unlikely(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio))) { + printk(KERN_ERR "bfin-gpio: GPIO %d is already reserved!\n", gpio); + dump_stack(); + local_irq_restore(flags); + return -EBUSY; + } + + if (unlikely(reserved_peri_map[gpio_bank(gpio)] & gpio_bit(gpio))) { + printk(KERN_ERR + "bfin-gpio: GPIO %d is already reserved as Peripheral!\n", gpio); + dump_stack(); + local_irq_restore(flags); + return -EBUSY; + } + + reserved_gpio_map[gpio_bank(gpio)] |= gpio_bit(gpio); + + local_irq_restore(flags); + + port_setup(gpio, GPIO_USAGE); + + return 0; +} +EXPORT_SYMBOL(gpio_request); + +void gpio_free(unsigned short gpio) +{ + unsigned long flags; + + if (check_gpio(gpio) < 0) + return; + + local_irq_save(flags); + + if (unlikely(!(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio)))) { + printk(KERN_ERR "bfin-gpio: GPIO %d wasn't reserved!\n", gpio); + dump_stack(); + local_irq_restore(flags); + return; + } + + reserved_gpio_map[gpio_bank(gpio)] &= ~gpio_bit(gpio); + + local_irq_restore(flags); +} +EXPORT_SYMBOL(gpio_free); + +void gpio_direction_input(unsigned short gpio) +{ + unsigned long flags; + + BUG_ON(!(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio))); + + local_irq_save(flags); + gpio_array[gpio_bank(gpio)]->port_dir_clear = gpio_bit(gpio); + gpio_array[gpio_bank(gpio)]->port_inen |= gpio_bit(gpio); + local_irq_restore(flags); +} +EXPORT_SYMBOL(gpio_direction_input); + +void gpio_direction_output(unsigned short gpio) +{ + unsigned long flags; + + BUG_ON(!(reserved_gpio_map[gpio_bank(gpio)] & gpio_bit(gpio))); + + local_irq_save(flags); + gpio_array[gpio_bank(gpio)]->port_inen &= ~gpio_bit(gpio); + gpio_array[gpio_bank(gpio)]->port_dir_set = gpio_bit(gpio); + local_irq_restore(flags); +} +EXPORT_SYMBOL(gpio_direction_output); + +void gpio_set_value(unsigned short gpio, unsigned short arg) +{ + if (arg) + gpio_array[gpio_bank(gpio)]->port_set = gpio_bit(gpio); + else + gpio_array[gpio_bank(gpio)]->port_clear = gpio_bit(gpio); + +} +EXPORT_SYMBOL(gpio_set_value); + +unsigned short gpio_get_value(unsigned short gpio) +{ + return (1 & (gpio_array[gpio_bank(gpio)]->port_data >> gpio_sub_n(gpio))); +} +EXPORT_SYMBOL(gpio_get_value); |