diff options
Diffstat (limited to 'arch/arm/plat-samsung/include/plat/gpio-core.h')
| -rw-r--r-- | arch/arm/plat-samsung/include/plat/gpio-core.h | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/arch/arm/plat-samsung/include/plat/gpio-core.h b/arch/arm/plat-samsung/include/plat/gpio-core.h new file mode 100644 index 000000000000..e358c7da8480 --- /dev/null +++ b/arch/arm/plat-samsung/include/plat/gpio-core.h @@ -0,0 +1,154 @@ +/* linux/arch/arm/plat-s3c/include/plat/gpio-core.h + * + * Copyright 2008 Simtec Electronics + * http://armlinux.simtec.co.uk/ + * Ben Dooks <ben@simtec.co.uk> + * + * S3C Platform - GPIO core + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. +*/ + +#define GPIOCON_OFF (0x00) +#define GPIODAT_OFF (0x04) + +#define con_4bit_shift(__off) ((__off) * 4) + +/* Define the core gpiolib support functions that the s3c platforms may + * need to extend or change depending on the hardware and the s3c chip + * selected at build or found at run time. + * + * These definitions are not intended for driver inclusion, there is + * nothing here that should not live outside the platform and core + * specific code. +*/ + +struct s3c_gpio_chip; + +/** + * struct s3c_gpio_pm - power management (suspend/resume) information + * @save: Routine to save the state of the GPIO block + * @resume: Routine to resume the GPIO block. + */ +struct s3c_gpio_pm { + void (*save)(struct s3c_gpio_chip *chip); + void (*resume)(struct s3c_gpio_chip *chip); +}; + +struct s3c_gpio_cfg; + +/** + * struct s3c_gpio_chip - wrapper for specific implementation of gpio + * @chip: The chip structure to be exported via gpiolib. + * @base: The base pointer to the gpio configuration registers. + * @config: special function and pull-resistor control information. + * @lock: Lock for exclusive access to this gpio bank. + * @pm_save: Save information for suspend/resume support. + * + * This wrapper provides the necessary information for the Samsung + * specific gpios being registered with gpiolib. + * + * The lock protects each gpio bank from multiple access of the shared + * configuration registers, or from reading of data whilst another thread + * is writing to the register set. + * + * Each chip has its own lock to avoid any contention between different + * CPU cores trying to get one lock for different GPIO banks, where each + * bank of GPIO has its own register space and configuration registers. + */ +struct s3c_gpio_chip { + struct gpio_chip chip; + struct s3c_gpio_cfg *config; + struct s3c_gpio_pm *pm; + void __iomem *base; + spinlock_t lock; +#ifdef CONFIG_PM + u32 pm_save[4]; +#endif +}; + +static inline struct s3c_gpio_chip *to_s3c_gpio(struct gpio_chip *gpc) +{ + return container_of(gpc, struct s3c_gpio_chip, chip); +} + +/** s3c_gpiolib_add() - add the s3c specific version of a gpio_chip. + * @chip: The chip to register + * + * This is a wrapper to gpiochip_add() that takes our specific gpio chip + * information and makes the necessary alterations for the platform and + * notes the information for use with the configuration systems and any + * other parts of the system. + */ +extern void s3c_gpiolib_add(struct s3c_gpio_chip *chip); + +/* CONFIG_S3C_GPIO_TRACK enables the tracking of the s3c specific gpios + * for use with the configuration calls, and other parts of the s3c gpiolib + * support code. + * + * Not all s3c support code will need this, as some configurations of cpu + * may only support one or two different configuration options and have an + * easy gpio to s3c_gpio_chip mapping function. If this is the case, then + * the machine support file should provide its own s3c_gpiolib_getchip() + * and any other necessary functions. + */ + +/** + * samsung_gpiolib_add_4bit_chips - 4bit single register GPIO config. + * @chip: The gpio chip that is being configured. + * @nr_chips: The no of chips (gpio ports) for the GPIO being configured. + * + * This helper deal with the GPIO cases where the control register has 4 bits + * of control per GPIO, generally in the form of: + * 0000 = Input + * 0001 = Output + * others = Special functions (dependant on bank) + * + * Note, since the code to deal with the case where there are two control + * registers instead of one, we do not have a separate set of function + * (samsung_gpiolib_add_4bit2_chips)for each case. + */ +extern void samsung_gpiolib_add_4bit_chips(struct s3c_gpio_chip *chip, + int nr_chips); +extern void samsung_gpiolib_add_4bit2_chips(struct s3c_gpio_chip *chip, + int nr_chips); + +extern void samsung_gpiolib_add_4bit(struct s3c_gpio_chip *chip); +extern void samsung_gpiolib_add_4bit2(struct s3c_gpio_chip *chip); + +/* exported for core SoC support to change */ +extern struct s3c_gpio_cfg s3c24xx_gpiocfg_default; + +#ifdef CONFIG_S3C_GPIO_TRACK +extern struct s3c_gpio_chip *s3c_gpios[S3C_GPIO_END]; + +static inline struct s3c_gpio_chip *s3c_gpiolib_getchip(unsigned int chip) +{ + return (chip < S3C_GPIO_END) ? s3c_gpios[chip] : NULL; +} +#else +/* machine specific code should provide s3c_gpiolib_getchip */ + +#include <mach/gpio-track.h> + +static inline void s3c_gpiolib_track(struct s3c_gpio_chip *chip) { } +#endif + +#ifdef CONFIG_PM +extern struct s3c_gpio_pm s3c_gpio_pm_1bit; +extern struct s3c_gpio_pm s3c_gpio_pm_2bit; +extern struct s3c_gpio_pm s3c_gpio_pm_4bit; +#define __gpio_pm(x) x +#else +#define s3c_gpio_pm_1bit NULL +#define s3c_gpio_pm_2bit NULL +#define s3c_gpio_pm_4bit NULL +#define __gpio_pm(x) NULL + +#endif /* CONFIG_PM */ + +/* locking wrappers to deal with multiple access to the same gpio bank */ +#define s3c_gpio_lock(_oc, _fl) spin_lock_irqsave(&(_oc)->lock, _fl) +#define s3c_gpio_unlock(_oc, _fl) spin_unlock_irqrestore(&(_oc)->lock, _fl) |