diff options
Diffstat (limited to 'target/linux/rdc/files-2.6.30/arch/x86/mach-rdc321x/gpio.c')
| -rw-r--r-- | target/linux/rdc/files-2.6.30/arch/x86/mach-rdc321x/gpio.c | 198 |
1 files changed, 198 insertions, 0 deletions
diff --git a/target/linux/rdc/files-2.6.30/arch/x86/mach-rdc321x/gpio.c b/target/linux/rdc/files-2.6.30/arch/x86/mach-rdc321x/gpio.c new file mode 100644 index 000000000..c7eff5d2c --- /dev/null +++ b/target/linux/rdc/files-2.6.30/arch/x86/mach-rdc321x/gpio.c @@ -0,0 +1,198 @@ +/* + * GPIO support for RDC SoC R3210/R8610 + * + * Copyright (C) 2007, Florian Fainelli <florian@openwrt.org> + * Copyright (C) 2008, Volker Weiss <dev@tintuc.de> + * + * 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, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + */ + + +#include <linux/spinlock.h> +#include <linux/io.h> +#include <linux/types.h> +#include <linux/module.h> + +#include <asm/mach-rdc321x/gpio.h> +#include <asm/mach-rdc321x/rdc321x_defs.h> + + +/* spin lock to protect our private copy of GPIO data register plus + the access to PCI conf registers. */ +static DEFINE_SPINLOCK(gpio_lock); + +/* copy of GPIO data registers */ +static u32 gpio_data_reg1; +static u32 gpio_data_reg2; + +static u32 gpio_request_data[2]; + + +static inline void rdc321x_conf_write(unsigned addr, u32 value) +{ + outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR); + outl(value, RDC3210_CFGREG_DATA); +} + +static inline void rdc321x_conf_or(unsigned addr, u32 value) +{ + outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR); + value |= inl(RDC3210_CFGREG_DATA); + outl(value, RDC3210_CFGREG_DATA); +} + +static inline u32 rdc321x_conf_read(unsigned addr) +{ + outl((1 << 31) | (7 << 11) | addr, RDC3210_CFGREG_ADDR); + + return inl(RDC3210_CFGREG_DATA); +} + +/* configure pin as GPIO */ +static void rdc321x_configure_gpio(unsigned gpio) +{ + unsigned long flags; + + spin_lock_irqsave(&gpio_lock, flags); + rdc321x_conf_or(gpio < 32 + ? RDC321X_GPIO_CTRL_REG1 : RDC321X_GPIO_CTRL_REG2, + 1 << (gpio & 0x1f)); + spin_unlock_irqrestore(&gpio_lock, flags); +} + +/* initially setup the 2 copies of the gpio data registers. + This function is called before the platform setup code. */ +static int __init rdc321x_gpio_setup(void) +{ + /* this might not be, what others (BIOS, bootloader, etc.) + wrote to these registers before, but it's a good guess. Still + better than just using 0xffffffff. */ + + gpio_data_reg1 = rdc321x_conf_read(RDC321X_GPIO_DATA_REG1); + gpio_data_reg2 = rdc321x_conf_read(RDC321X_GPIO_DATA_REG2); + + return 0; +} + +/* determine, if gpio number is valid */ +static inline int rdc321x_is_gpio(unsigned gpio) +{ + return gpio <= RDC321X_MAX_GPIO; +} + +/* request GPIO */ +int rdc_gpio_request(unsigned gpio, const char *label) +{ + unsigned long flags; + + if (!rdc321x_is_gpio(gpio)) + return -EINVAL; + + spin_lock_irqsave(&gpio_lock, flags); + if (gpio_request_data[(gpio & 0x20) ? 1 : 0] & (1 << (gpio & 0x1f))) + goto inuse; + gpio_request_data[(gpio & 0x20) ? 1 : 0] |= (1 << (gpio & 0x1f)); + spin_unlock_irqrestore(&gpio_lock, flags); + + return 0; +inuse: + spin_unlock_irqrestore(&gpio_lock, flags); + return -EINVAL; +} +EXPORT_SYMBOL(rdc_gpio_request); + +/* release previously-claimed GPIO */ +void rdc_gpio_free(unsigned gpio) +{ + unsigned long flags; + + if (!rdc321x_is_gpio(gpio)) + return; + + spin_lock_irqsave(&gpio_lock, flags); + gpio_request_data[(gpio & 0x20) ? 1 : 0] &= ~(1 << (gpio & 0x1f)); + spin_unlock_irqrestore(&gpio_lock, flags); +} +EXPORT_SYMBOL(rdc_gpio_free); + +/* read GPIO pin */ +int rdc_gpio_get_value(unsigned gpio) +{ + u32 reg; + unsigned long flags; + + spin_lock_irqsave(&gpio_lock, flags); + reg = rdc321x_conf_read(gpio < 32 + ? RDC321X_GPIO_DATA_REG1 : RDC321X_GPIO_DATA_REG2); + spin_unlock_irqrestore(&gpio_lock, flags); + + return (1 << (gpio & 0x1f)) & reg ? 1 : 0; +} +EXPORT_SYMBOL(rdc_gpio_get_value); + +/* set GPIO pin to value */ +void rdc_gpio_set_value(unsigned gpio, int value) +{ + unsigned long flags; + u32 reg; + + reg = 1 << (gpio & 0x1f); + if (gpio < 32) { + spin_lock_irqsave(&gpio_lock, flags); + if (value) + gpio_data_reg1 |= reg; + else + gpio_data_reg1 &= ~reg; + rdc321x_conf_write(RDC321X_GPIO_DATA_REG1, gpio_data_reg1); + spin_unlock_irqrestore(&gpio_lock, flags); + } else { + spin_lock_irqsave(&gpio_lock, flags); + if (value) + gpio_data_reg2 |= reg; + else + gpio_data_reg2 &= ~reg; + rdc321x_conf_write(RDC321X_GPIO_DATA_REG2, gpio_data_reg2); + spin_unlock_irqrestore(&gpio_lock, flags); + } +} +EXPORT_SYMBOL(rdc_gpio_set_value); + +/* configure GPIO pin as input */ +int rdc_gpio_direction_input(unsigned gpio) +{ + if (!rdc321x_is_gpio(gpio)) + return -EINVAL; + + rdc321x_configure_gpio(gpio); + + return 0; +} +EXPORT_SYMBOL(rdc_gpio_direction_input); + +/* configure GPIO pin as output and set value */ +int rdc_gpio_direction_output(unsigned gpio, int value) +{ + if (!rdc321x_is_gpio(gpio)) + return -EINVAL; + + gpio_set_value(gpio, value); + rdc321x_configure_gpio(gpio); + + return 0; +} +EXPORT_SYMBOL(rdc_gpio_direction_output); + +arch_initcall(rdc321x_gpio_setup); |