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| -rw-r--r-- | arch/powerpc/include/asm/mpc85xx_gpio.h | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/mpc85xx_gpio.h b/arch/powerpc/include/asm/mpc85xx_gpio.h new file mode 100644 index 0000000..5a608a5 --- /dev/null +++ b/arch/powerpc/include/asm/mpc85xx_gpio.h @@ -0,0 +1,123 @@ +/* + * Copyright 2010 eXMeritus, A Boeing Company + * + * 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., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#ifndef POWERPC_ASM_MPC85XX_GPIO_H_ +#define POWERPC_ASM_MPC85XX_GPIO_H_ + +# include <asm/immap_85xx.h> + +/* + * The following internal functions are an MPC85XX-specific GPIO API which + * allows setting and querying multiple GPIOs in a single operation. + * + * All of these look relatively large, but the arguments are almost always + * constants, so they compile down to just a few instructions and a + * memory-mapped IO operation or two. + */ +static inline void mpc85xx_gpio_set(unsigned int mask, + unsigned int dir, unsigned int val) +{ + ccsr_gpio_t *gpio = (void *)(CONFIG_SYS_MPC85xx_GPIO_ADDR + 0xc00); + + /* First mask off the unwanted parts of "dir" and "val" */ + dir &= mask; + val &= mask; + + /* Now read in the values we're supposed to preserve */ + dir |= (in_be32(&gpio->gpdir) & ~mask); + val |= (in_be32(&gpio->gpdat) & ~mask); + + /* + * Poke the new output values first, then set the direction. This + * helps to avoid transient data when switching from input to output + * and vice versa. + */ + out_be32(&gpio->gpdat, val); + out_be32(&gpio->gpdir, dir); +} + +static inline void mpc85xx_gpio_set_in(unsigned int gpios) +{ + mpc85xx_gpio_set(gpios, 0x00000000, 0x00000000); +} + +static inline void mpc85xx_gpio_set_low(unsigned int gpios) +{ + mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0x00000000); +} + +static inline void mpc85xx_gpio_set_high(unsigned int gpios) +{ + mpc85xx_gpio_set(gpios, 0xFFFFFFFF, 0xFFFFFFFF); +} + +static inline unsigned int mpc85xx_gpio_get(unsigned int mask) +{ + ccsr_gpio_t *gpio = (void *)(CONFIG_SYS_MPC85xx_GPIO_ADDR + 0xc00); + + /* Read the requested values */ + return in_be32(&gpio->gpdat) & mask; +} + +/* + * These implement the generic Linux GPIO API on top of the other functions + * in this header. + */ +static inline int gpio_request(unsigned gpio, const char *label) +{ + /* Compatibility shim */ + return 0; +} + +static inline void gpio_free(unsigned gpio) +{ + /* Compatibility shim */ +} + +static inline int gpio_direction_input(unsigned gpio) +{ + mpc85xx_gpio_set_in(1U << gpio); + return 0; +} + +static inline int gpio_direction_output(unsigned gpio, int value) +{ + mpc85xx_gpio_set_low(1U << gpio); + return 0; +} + +static inline int gpio_get_value(unsigned gpio) +{ + return !!mpc85xx_gpio_get(1U << gpio); +} + +static inline void gpio_set_value(unsigned gpio, int value) +{ + if (value) + mpc85xx_gpio_set_high(1U << gpio); + else + mpc85xx_gpio_set_low(1U << gpio); +} + +static inline int gpio_is_valid(int gpio) +{ + return (gpio >= 0) && (gpio < 32); +} + +#endif /* not POWERPC_ASM_MPC85XX_GPIO_H_ */ |