diff options
Diffstat (limited to 'arch/arm/mach-ep93xx/gpio.c')
| -rw-r--r-- | arch/arm/mach-ep93xx/gpio.c | 235 |
1 files changed, 231 insertions, 4 deletions
diff --git a/arch/arm/mach-ep93xx/gpio.c b/arch/arm/mach-ep93xx/gpio.c index 1ea8871e03a..cc377ae8c42 100644 --- a/arch/arm/mach-ep93xx/gpio.c +++ b/arch/arm/mach-ep93xx/gpio.c @@ -13,6 +13,8 @@ * published by the Free Software Foundation. */ +#define pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt + #include <linux/init.h> #include <linux/module.h> #include <linux/seq_file.h> @@ -22,6 +24,235 @@ #include <mach/hardware.h> +/************************************************************************* + * GPIO handling for EP93xx + *************************************************************************/ +static unsigned char gpio_int_unmasked[3]; +static unsigned char gpio_int_enabled[3]; +static unsigned char gpio_int_type1[3]; +static unsigned char gpio_int_type2[3]; +static unsigned char gpio_int_debounce[3]; + +/* Port ordering is: A B F */ +static const u8 int_type1_register_offset[3] = { 0x90, 0xac, 0x4c }; +static const u8 int_type2_register_offset[3] = { 0x94, 0xb0, 0x50 }; +static const u8 eoi_register_offset[3] = { 0x98, 0xb4, 0x54 }; +static const u8 int_en_register_offset[3] = { 0x9c, 0xb8, 0x58 }; +static const u8 int_debounce_register_offset[3] = { 0xa8, 0xc4, 0x64 }; + +void ep93xx_gpio_update_int_params(unsigned port) +{ + BUG_ON(port > 2); + + __raw_writeb(0, EP93XX_GPIO_REG(int_en_register_offset[port])); + + __raw_writeb(gpio_int_type2[port], + EP93XX_GPIO_REG(int_type2_register_offset[port])); + + __raw_writeb(gpio_int_type1[port], + EP93XX_GPIO_REG(int_type1_register_offset[port])); + + __raw_writeb(gpio_int_unmasked[port] & gpio_int_enabled[port], + EP93XX_GPIO_REG(int_en_register_offset[port])); +} + +void ep93xx_gpio_int_mask(unsigned line) +{ + gpio_int_unmasked[line >> 3] &= ~(1 << (line & 7)); +} + +void ep93xx_gpio_int_debounce(unsigned int irq, int enable) +{ + int line = irq_to_gpio(irq); + int port = line >> 3; + int port_mask = 1 << (line & 7); + + if (enable) + gpio_int_debounce[port] |= port_mask; + else + gpio_int_debounce[port] &= ~port_mask; + + __raw_writeb(gpio_int_debounce[port], + EP93XX_GPIO_REG(int_debounce_register_offset[port])); +} +EXPORT_SYMBOL(ep93xx_gpio_int_debounce); + +static void ep93xx_gpio_ab_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + unsigned char status; + int i; + + status = __raw_readb(EP93XX_GPIO_A_INT_STATUS); + for (i = 0; i < 8; i++) { + if (status & (1 << i)) { + int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_A(0)) + i; + generic_handle_irq(gpio_irq); + } + } + + status = __raw_readb(EP93XX_GPIO_B_INT_STATUS); + for (i = 0; i < 8; i++) { + if (status & (1 << i)) { + int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_B(0)) + i; + generic_handle_irq(gpio_irq); + } + } +} + +static void ep93xx_gpio_f_irq_handler(unsigned int irq, struct irq_desc *desc) +{ + /* + * map discontiguous hw irq range to continous sw irq range: + * + * IRQ_EP93XX_GPIO{0..7}MUX -> gpio_to_irq(EP93XX_GPIO_LINE_F({0..7}) + */ + int port_f_idx = ((irq + 1) & 7) ^ 4; /* {19..22,47..50} -> {0..7} */ + int gpio_irq = gpio_to_irq(EP93XX_GPIO_LINE_F(0)) + port_f_idx; + + generic_handle_irq(gpio_irq); +} + +static void ep93xx_gpio_irq_ack(unsigned int irq) +{ + int line = irq_to_gpio(irq); + int port = line >> 3; + int port_mask = 1 << (line & 7); + + if ((irq_desc[irq].status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) { + gpio_int_type2[port] ^= port_mask; /* switch edge direction */ + ep93xx_gpio_update_int_params(port); + } + + __raw_writeb(port_mask, EP93XX_GPIO_REG(eoi_register_offset[port])); +} + +static void ep93xx_gpio_irq_mask_ack(unsigned int irq) +{ + int line = irq_to_gpio(irq); + int port = line >> 3; + int port_mask = 1 << (line & 7); + + if ((irq_desc[irq].status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) + gpio_int_type2[port] ^= port_mask; /* switch edge direction */ + + gpio_int_unmasked[port] &= ~port_mask; + ep93xx_gpio_update_int_params(port); + + __raw_writeb(port_mask, EP93XX_GPIO_REG(eoi_register_offset[port])); +} + +static void ep93xx_gpio_irq_mask(unsigned int irq) +{ + int line = irq_to_gpio(irq); + int port = line >> 3; + + gpio_int_unmasked[port] &= ~(1 << (line & 7)); + ep93xx_gpio_update_int_params(port); +} + +static void ep93xx_gpio_irq_unmask(unsigned int irq) +{ + int line = irq_to_gpio(irq); + int port = line >> 3; + + gpio_int_unmasked[port] |= 1 << (line & 7); + ep93xx_gpio_update_int_params(port); +} + +/* + * gpio_int_type1 controls whether the interrupt is level (0) or + * edge (1) triggered, while gpio_int_type2 controls whether it + * triggers on low/falling (0) or high/rising (1). + */ +static int ep93xx_gpio_irq_type(unsigned int irq, unsigned int type) +{ + struct irq_desc *desc = irq_desc + irq; + const int gpio = irq_to_gpio(irq); + const int port = gpio >> 3; + const int port_mask = 1 << (gpio & 7); + + gpio_direction_input(gpio); + + switch (type) { + case IRQ_TYPE_EDGE_RISING: + gpio_int_type1[port] |= port_mask; + gpio_int_type2[port] |= port_mask; + desc->handle_irq = handle_edge_irq; + break; + case IRQ_TYPE_EDGE_FALLING: + gpio_int_type1[port] |= port_mask; + gpio_int_type2[port] &= ~port_mask; + desc->handle_irq = handle_edge_irq; + break; + case IRQ_TYPE_LEVEL_HIGH: + gpio_int_type1[port] &= ~port_mask; + gpio_int_type2[port] |= port_mask; + desc->handle_irq = handle_level_irq; + break; + case IRQ_TYPE_LEVEL_LOW: + gpio_int_type1[port] &= ~port_mask; + gpio_int_type2[port] &= ~port_mask; + desc->handle_irq = handle_level_irq; + break; + case IRQ_TYPE_EDGE_BOTH: + gpio_int_type1[port] |= port_mask; + /* set initial polarity based on current input level */ + if (gpio_get_value(gpio)) + gpio_int_type2[port] &= ~port_mask; /* falling */ + else + gpio_int_type2[port] |= port_mask; /* rising */ + desc->handle_irq = handle_edge_irq; + break; + default: + pr_err("failed to set irq type %d for gpio %d\n", type, gpio); + return -EINVAL; + } + + gpio_int_enabled[port] |= port_mask; + + desc->status &= ~IRQ_TYPE_SENSE_MASK; + desc->status |= type & IRQ_TYPE_SENSE_MASK; + + ep93xx_gpio_update_int_params(port); + + return 0; +} + +static struct irq_chip ep93xx_gpio_irq_chip = { + .name = "GPIO", + .ack = ep93xx_gpio_irq_ack, + .mask_ack = ep93xx_gpio_irq_mask_ack, + .mask = ep93xx_gpio_irq_mask, + .unmask = ep93xx_gpio_irq_unmask, + .set_type = ep93xx_gpio_irq_type, +}; + +void __init ep93xx_gpio_init_irq(void) +{ + int gpio_irq; + + for (gpio_irq = gpio_to_irq(0); + gpio_irq <= gpio_to_irq(EP93XX_GPIO_LINE_MAX_IRQ); ++gpio_irq) { + set_irq_chip(gpio_irq, &ep93xx_gpio_irq_chip); + set_irq_handler(gpio_irq, handle_level_irq); + set_irq_flags(gpio_irq, IRQF_VALID); + } + + set_irq_chained_handler(IRQ_EP93XX_GPIO_AB, ep93xx_gpio_ab_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO0MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO1MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO2MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO3MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO4MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO5MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO6MUX, ep93xx_gpio_f_irq_handler); + set_irq_chained_handler(IRQ_EP93XX_GPIO7MUX, ep93xx_gpio_f_irq_handler); +} + + +/************************************************************************* + * gpiolib interface for EP93xx on-chip GPIOs + *************************************************************************/ struct ep93xx_gpio_chip { struct gpio_chip chip; @@ -31,10 +262,6 @@ struct ep93xx_gpio_chip { #define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip) -/* From core.c */ -extern void ep93xx_gpio_int_mask(unsigned line); -extern void ep93xx_gpio_update_int_params(unsigned port); - static int ep93xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset) { struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip); |