diff options
Diffstat (limited to 'arch/arm/mach-pnx4008/gpio.c')
-rw-r--r-- | arch/arm/mach-pnx4008/gpio.c | 330 |
1 files changed, 330 insertions, 0 deletions
diff --git a/arch/arm/mach-pnx4008/gpio.c b/arch/arm/mach-pnx4008/gpio.c new file mode 100644 index 0000000..e1ce050 --- /dev/null +++ b/arch/arm/mach-pnx4008/gpio.c @@ -0,0 +1,330 @@ +/* + * arch/arm/mach-pnx4008/gpio.c + * + * PNX4008 GPIO driver + * + * Author: Dmitry Chigirev <source@mvista.com> + * + * Based on reference code by Iwo Mergler and Z.Tabaaloute from Philips: + * Copyright (c) 2005 Koninklijke Philips Electronics N.V. + * + * 2005 (c) MontaVista Software, Inc. This file is licensed under + * the terms of the GNU General Public License version 2. This program + * is licensed "as is" without any warranty of any kind, whether express + * or implied. + */ + +#include <linux/config.h> +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <asm/semaphore.h> +#include <asm/io.h> +#include <asm/arch/platform.h> +#include <asm/arch/gpio.h> + +/* register definitions */ +#define PIO_VA_BASE IO_ADDRESS(PNX4008_PIO_BASE) + +#define PIO_INP_STATE (0x00U) +#define PIO_OUTP_SET (0x04U) +#define PIO_OUTP_CLR (0x08U) +#define PIO_OUTP_STATE (0x0CU) +#define PIO_DRV_SET (0x10U) +#define PIO_DRV_CLR (0x14U) +#define PIO_DRV_STATE (0x18U) +#define PIO_SDINP_STATE (0x1CU) +#define PIO_SDOUTP_SET (0x20U) +#define PIO_SDOUTP_CLR (0x24U) +#define PIO_MUX_SET (0x28U) +#define PIO_MUX_CLR (0x2CU) +#define PIO_MUX_STATE (0x30U) + +static inline void gpio_lock(void) +{ + local_irq_disable(); +} + +static inline void gpio_unlock(void) +{ + local_irq_enable(); +} + +/* Inline functions */ +static inline int gpio_read_bit(u32 reg, int gpio) +{ + u32 bit, val; + int ret = -EFAULT; + + if (gpio < 0) + goto out; + + bit = GPIO_BIT(gpio); + if (bit) { + val = __raw_readl(PIO_VA_BASE + reg); + ret = (val & bit) ? 1 : 0; + } +out: + return ret; +} + +static inline int gpio_set_bit(u32 reg, int gpio) +{ + u32 bit, val; + int ret = -EFAULT; + + if (gpio < 0) + goto out; + + bit = GPIO_BIT(gpio); + if (bit) { + val = __raw_readl(PIO_VA_BASE + reg); + val |= bit; + __raw_writel(val, PIO_VA_BASE + reg); + ret = 0; + } +out: + return ret; +} + +/* Very simple access control, bitmap for allocated/free */ +static unsigned long access_map[4]; +#define INP_INDEX 0 +#define OUTP_INDEX 1 +#define GPIO_INDEX 2 +#define MUX_INDEX 3 + +/*GPIO to Input Mapping */ +static short gpio_to_inp_map[32] = { + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, 10, 11, 12, 13, 14, 24, -1 +}; + +/*GPIO to Mux Mapping */ +static short gpio_to_mux_map[32] = { + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, 0, 1, 4, 5, -1 +}; + +/*Output to Mux Mapping */ +static short outp_to_mux_map[32] = { + -1, -1, -1, 6, -1, -1, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1, + -1, -1, -1, -1, -1, 2, -1, -1, + -1, -1, -1, -1, -1, -1, -1, -1 +}; + +int pnx4008_gpio_register_pin(unsigned short pin) +{ + unsigned long bit = GPIO_BIT(pin); + int ret = -EBUSY; /* Already in use */ + + gpio_lock(); + + if (GPIO_ISBID(pin)) { + if (access_map[GPIO_INDEX] & bit) + goto out; + access_map[GPIO_INDEX] |= bit; + + } else if (GPIO_ISRAM(pin)) { + if (access_map[GPIO_INDEX] & bit) + goto out; + access_map[GPIO_INDEX] |= bit; + + } else if (GPIO_ISMUX(pin)) { + if (access_map[MUX_INDEX] & bit) + goto out; + access_map[MUX_INDEX] |= bit; + + } else if (GPIO_ISOUT(pin)) { + if (access_map[OUTP_INDEX] & bit) + goto out; + access_map[OUTP_INDEX] |= bit; + + } else if (GPIO_ISIN(pin)) { + if (access_map[INP_INDEX] & bit) + goto out; + access_map[INP_INDEX] |= bit; + } else + goto out; + ret = 0; + +out: + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_register_pin); + +int pnx4008_gpio_unregister_pin(unsigned short pin) +{ + unsigned long bit = GPIO_BIT(pin); + int ret = -EFAULT; /* Not registered */ + + gpio_lock(); + + if (GPIO_ISBID(pin)) { + if (~access_map[GPIO_INDEX] & bit) + goto out; + access_map[GPIO_INDEX] &= ~bit; + } else if (GPIO_ISRAM(pin)) { + if (~access_map[GPIO_INDEX] & bit) + goto out; + access_map[GPIO_INDEX] &= ~bit; + } else if (GPIO_ISMUX(pin)) { + if (~access_map[MUX_INDEX] & bit) + goto out; + access_map[MUX_INDEX] &= ~bit; + } else if (GPIO_ISOUT(pin)) { + if (~access_map[OUTP_INDEX] & bit) + goto out; + access_map[OUTP_INDEX] &= ~bit; + } else if (GPIO_ISIN(pin)) { + if (~access_map[INP_INDEX] & bit) + goto out; + access_map[INP_INDEX] &= ~bit; + } else + goto out; + ret = 0; + +out: + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_unregister_pin); + +unsigned long pnx4008_gpio_read_pin(unsigned short pin) +{ + unsigned long ret = -EFAULT; + int gpio = GPIO_BIT_MASK(pin); + gpio_lock(); + if (GPIO_ISOUT(pin)) { + ret = gpio_read_bit(PIO_OUTP_STATE, gpio); + } else if (GPIO_ISRAM(pin)) { + if (gpio_read_bit(PIO_DRV_STATE, gpio) == 0) { + ret = gpio_read_bit(PIO_SDINP_STATE, gpio); + } + } else if (GPIO_ISBID(pin)) { + ret = gpio_read_bit(PIO_DRV_STATE, gpio); + if (ret > 0) + ret = gpio_read_bit(PIO_OUTP_STATE, gpio); + else if (ret == 0) + ret = + gpio_read_bit(PIO_INP_STATE, gpio_to_inp_map[gpio]); + } else if (GPIO_ISIN(pin)) { + ret = gpio_read_bit(PIO_INP_STATE, gpio); + } + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_read_pin); + +/* Write Value to output */ +int pnx4008_gpio_write_pin(unsigned short pin, int output) +{ + int gpio = GPIO_BIT_MASK(pin); + int ret = -EFAULT; + + gpio_lock(); + if (GPIO_ISOUT(pin)) { + printk( "writing '%x' to '%x'\n", + gpio, output ? PIO_OUTP_SET : PIO_OUTP_CLR ); + ret = gpio_set_bit(output ? PIO_OUTP_SET : PIO_OUTP_CLR, gpio); + } else if (GPIO_ISRAM(pin)) { + if (gpio_read_bit(PIO_DRV_STATE, gpio) > 0) + ret = gpio_set_bit(output ? PIO_SDOUTP_SET : + PIO_SDOUTP_CLR, gpio); + } else if (GPIO_ISBID(pin)) { + if (gpio_read_bit(PIO_DRV_STATE, gpio) > 0) + ret = gpio_set_bit(output ? PIO_OUTP_SET : + PIO_OUTP_CLR, gpio); + } + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_write_pin); + +/* Value = 1 : Set GPIO pin as output */ +/* Value = 0 : Set GPIO pin as input */ +int pnx4008_gpio_set_pin_direction(unsigned short pin, int output) +{ + int gpio = GPIO_BIT_MASK(pin); + int ret = -EFAULT; + + gpio_lock(); + if (GPIO_ISBID(pin) || GPIO_ISRAM(pin)) { + ret = gpio_set_bit(output ? PIO_DRV_SET : PIO_DRV_CLR, gpio); + } + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_set_pin_direction); + +/* Read GPIO pin direction: 0= pin used as input, 1= pin used as output*/ +int pnx4008_gpio_read_pin_direction(unsigned short pin) +{ + int gpio = GPIO_BIT_MASK(pin); + int ret = -EFAULT; + + gpio_lock(); + if (GPIO_ISBID(pin) || GPIO_ISRAM(pin)) { + ret = gpio_read_bit(PIO_DRV_STATE, gpio); + } + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_read_pin_direction); + +/* Value = 1 : Set pin to muxed function */ +/* Value = 0 : Set pin as GPIO */ +int pnx4008_gpio_set_pin_mux(unsigned short pin, int output) +{ + int gpio = GPIO_BIT_MASK(pin); + int ret = -EFAULT; + + gpio_lock(); + if (GPIO_ISBID(pin)) { + ret = + gpio_set_bit(output ? PIO_MUX_SET : PIO_MUX_CLR, + gpio_to_mux_map[gpio]); + } else if (GPIO_ISOUT(pin)) { + ret = + gpio_set_bit(output ? PIO_MUX_SET : PIO_MUX_CLR, + outp_to_mux_map[gpio]); + } else if (GPIO_ISMUX(pin)) { + ret = gpio_set_bit(output ? PIO_MUX_SET : PIO_MUX_CLR, gpio); + } + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_set_pin_mux); + +/* Read pin mux function: 0= pin used as GPIO, 1= pin used for muxed function*/ +int pnx4008_gpio_read_pin_mux(unsigned short pin) +{ + int gpio = GPIO_BIT_MASK(pin); + int ret = -EFAULT; + + gpio_lock(); + if (GPIO_ISBID(pin)) { + ret = gpio_read_bit(PIO_MUX_STATE, gpio_to_mux_map[gpio]); + } else if (GPIO_ISOUT(pin)) { + ret = gpio_read_bit(PIO_MUX_STATE, outp_to_mux_map[gpio]); + } else if (GPIO_ISMUX(pin)) { + ret = gpio_read_bit(PIO_MUX_STATE, gpio); + } + gpio_unlock(); + return ret; +} + +EXPORT_SYMBOL(pnx4008_gpio_read_pin_mux); |