diff options
Diffstat (limited to 'include/linux/scx200_gpio.h')
| -rw-r--r-- | include/linux/scx200_gpio.h | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/include/linux/scx200_gpio.h b/include/linux/scx200_gpio.h new file mode 100644 index 000000000..6386ddbb6 --- /dev/null +++ b/include/linux/scx200_gpio.h @@ -0,0 +1,89 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +u32 scx200_gpio_configure(unsigned index, u32 set, u32 clear); + +extern unsigned scx200_gpio_base; +extern unsigned long scx200_gpio_shadow[2]; +extern struct nsc_gpio_ops scx200_gpio_ops; + +#define scx200_gpio_present() (scx200_gpio_base!=0) + +/* Definitions to make sure I do the same thing in all functions */ +#define __SCx200_GPIO_BANK unsigned bank = index>>5 +#define __SCx200_GPIO_IOADDR unsigned short ioaddr = scx200_gpio_base+0x10*bank +#define __SCx200_GPIO_SHADOW unsigned long *shadow = scx200_gpio_shadow+bank +#define __SCx200_GPIO_INDEX index &= 31 + +#define __SCx200_GPIO_OUT __asm__ __volatile__("outsl":"=mS" (shadow):"d" (ioaddr), "0" (shadow)) + +/* returns the value of the GPIO pin */ + +static inline int scx200_gpio_get(unsigned index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR + 0x04; + __SCx200_GPIO_INDEX; + + return (inl(ioaddr) & (1<<index)) ? 1 : 0; +} + +/* return the value driven on the GPIO signal (the value that will be + driven if the GPIO is configured as an output, it might not be the + state of the GPIO right now if the GPIO is configured as an input) */ + +static inline int scx200_gpio_current(unsigned index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_INDEX; + + return (scx200_gpio_shadow[bank] & (1<<index)) ? 1 : 0; +} + +/* drive the GPIO signal high */ + +static inline void scx200_gpio_set_high(unsigned index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + set_bit(index, shadow); /* __set_bit()? */ + __SCx200_GPIO_OUT; +} + +/* drive the GPIO signal low */ + +static inline void scx200_gpio_set_low(unsigned index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + clear_bit(index, shadow); /* __clear_bit()? */ + __SCx200_GPIO_OUT; +} + +/* drive the GPIO signal to state */ + +static inline void scx200_gpio_set(unsigned index, int state) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + if (state) + set_bit(index, shadow); + else + clear_bit(index, shadow); + __SCx200_GPIO_OUT; +} + +/* toggle the GPIO signal */ +static inline void scx200_gpio_change(unsigned index) { + __SCx200_GPIO_BANK; + __SCx200_GPIO_IOADDR; + __SCx200_GPIO_SHADOW; + __SCx200_GPIO_INDEX; + change_bit(index, shadow); + __SCx200_GPIO_OUT; +} + +#undef __SCx200_GPIO_BANK +#undef __SCx200_GPIO_IOADDR +#undef __SCx200_GPIO_SHADOW +#undef __SCx200_GPIO_INDEX +#undef __SCx200_GPIO_OUT |