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path: root/drivers/gpio/gpio-ep93xx.c
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Diffstat (limited to 'drivers/gpio/gpio-ep93xx.c')
-rw-r--r--drivers/gpio/gpio-ep93xx.c410
1 files changed, 410 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-ep93xx.c b/drivers/gpio/gpio-ep93xx.c
new file mode 100644
index 000000000000..415dce37b88c
--- /dev/null
+++ b/drivers/gpio/gpio-ep93xx.c
@@ -0,0 +1,410 @@
+/*
+ * linux/arch/arm/mach-ep93xx/gpio.c
+ *
+ * Generic EP93xx GPIO handling
+ *
+ * Copyright (c) 2008 Ryan Mallon <ryan@bluewatersys.com>
+ *
+ * Based on code originally from:
+ * linux/arch/arm/mach-ep93xx/core.c
+ *
+ * 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 pr_fmt(fmt) "ep93xx " KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/seq_file.h>
+#include <linux/io.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+
+#include <mach/hardware.h>
+
+/*************************************************************************
+ * Interrupt handling for EP93xx on-chip GPIOs
+ *************************************************************************/
+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 };
+
+static 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]));
+}
+
+static inline void ep93xx_gpio_int_mask(unsigned line)
+{
+ gpio_int_unmasked[line >> 3] &= ~(1 << (line & 7));
+}
+
+static void ep93xx_gpio_int_debounce(unsigned int irq, bool 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]));
+}
+
+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 continuous 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(struct irq_data *d)
+{
+ int line = irq_to_gpio(d->irq);
+ int port = line >> 3;
+ int port_mask = 1 << (line & 7);
+
+ if (irqd_get_trigger_type(d) == 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(struct irq_data *d)
+{
+ int line = irq_to_gpio(d->irq);
+ int port = line >> 3;
+ int port_mask = 1 << (line & 7);
+
+ if (irqd_get_trigger_type(d) == 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(struct irq_data *d)
+{
+ int line = irq_to_gpio(d->irq);
+ int port = line >> 3;
+
+ gpio_int_unmasked[port] &= ~(1 << (line & 7));
+ ep93xx_gpio_update_int_params(port);
+}
+
+static void ep93xx_gpio_irq_unmask(struct irq_data *d)
+{
+ int line = irq_to_gpio(d->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(struct irq_data *d, unsigned int type)
+{
+ const int gpio = irq_to_gpio(d->irq);
+ const int port = gpio >> 3;
+ const int port_mask = 1 << (gpio & 7);
+ irq_flow_handler_t handler;
+
+ gpio_direction_input(gpio);
+
+ switch (type) {
+ case IRQ_TYPE_EDGE_RISING:
+ gpio_int_type1[port] |= port_mask;
+ gpio_int_type2[port] |= port_mask;
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ gpio_int_type1[port] |= port_mask;
+ gpio_int_type2[port] &= ~port_mask;
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ gpio_int_type1[port] &= ~port_mask;
+ gpio_int_type2[port] |= port_mask;
+ handler = handle_level_irq;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ gpio_int_type1[port] &= ~port_mask;
+ gpio_int_type2[port] &= ~port_mask;
+ handler = 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 */
+ handler = handle_edge_irq;
+ break;
+ default:
+ pr_err("failed to set irq type %d for gpio %d\n", type, gpio);
+ return -EINVAL;
+ }
+
+ __irq_set_handler_locked(d->irq, handler);
+
+ gpio_int_enabled[port] |= port_mask;
+
+ ep93xx_gpio_update_int_params(port);
+
+ return 0;
+}
+
+static struct irq_chip ep93xx_gpio_irq_chip = {
+ .name = "GPIO",
+ .irq_ack = ep93xx_gpio_irq_ack,
+ .irq_mask_ack = ep93xx_gpio_irq_mask_ack,
+ .irq_mask = ep93xx_gpio_irq_mask,
+ .irq_unmask = ep93xx_gpio_irq_unmask,
+ .irq_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) {
+ irq_set_chip_and_handler(gpio_irq, &ep93xx_gpio_irq_chip,
+ handle_level_irq);
+ set_irq_flags(gpio_irq, IRQF_VALID);
+ }
+
+ irq_set_chained_handler(IRQ_EP93XX_GPIO_AB,
+ ep93xx_gpio_ab_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO0MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO1MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO2MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO3MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO4MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO5MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_chained_handler(IRQ_EP93XX_GPIO6MUX,
+ ep93xx_gpio_f_irq_handler);
+ irq_set_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;
+
+ void __iomem *data_reg;
+ void __iomem *data_dir_reg;
+};
+
+#define to_ep93xx_gpio_chip(c) container_of(c, struct ep93xx_gpio_chip, chip)
+
+static int ep93xx_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+ unsigned long flags;
+ u8 v;
+
+ local_irq_save(flags);
+ v = __raw_readb(ep93xx_chip->data_dir_reg);
+ v &= ~(1 << offset);
+ __raw_writeb(v, ep93xx_chip->data_dir_reg);
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static int ep93xx_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int val)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+ unsigned long flags;
+ int line;
+ u8 v;
+
+ local_irq_save(flags);
+
+ /* Set the value */
+ v = __raw_readb(ep93xx_chip->data_reg);
+ if (val)
+ v |= (1 << offset);
+ else
+ v &= ~(1 << offset);
+ __raw_writeb(v, ep93xx_chip->data_reg);
+
+ /* Drive as an output */
+ line = chip->base + offset;
+ if (line <= EP93XX_GPIO_LINE_MAX_IRQ) {
+ /* Ports A/B/F */
+ ep93xx_gpio_int_mask(line);
+ ep93xx_gpio_update_int_params(line >> 3);
+ }
+
+ v = __raw_readb(ep93xx_chip->data_dir_reg);
+ v |= (1 << offset);
+ __raw_writeb(v, ep93xx_chip->data_dir_reg);
+
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static int ep93xx_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+
+ return !!(__raw_readb(ep93xx_chip->data_reg) & (1 << offset));
+}
+
+static void ep93xx_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
+{
+ struct ep93xx_gpio_chip *ep93xx_chip = to_ep93xx_gpio_chip(chip);
+ unsigned long flags;
+ u8 v;
+
+ local_irq_save(flags);
+ v = __raw_readb(ep93xx_chip->data_reg);
+ if (val)
+ v |= (1 << offset);
+ else
+ v &= ~(1 << offset);
+ __raw_writeb(v, ep93xx_chip->data_reg);
+ local_irq_restore(flags);
+}
+
+static int ep93xx_gpio_set_debounce(struct gpio_chip *chip,
+ unsigned offset, unsigned debounce)
+{
+ int gpio = chip->base + offset;
+ int irq = gpio_to_irq(gpio);
+
+ if (irq < 0)
+ return -EINVAL;
+
+ ep93xx_gpio_int_debounce(irq, debounce ? true : false);
+
+ return 0;
+}
+
+#define EP93XX_GPIO_BANK(name, dr, ddr, base_gpio) \
+ { \
+ .chip = { \
+ .label = name, \
+ .direction_input = ep93xx_gpio_direction_input, \
+ .direction_output = ep93xx_gpio_direction_output, \
+ .get = ep93xx_gpio_get, \
+ .set = ep93xx_gpio_set, \
+ .base = base_gpio, \
+ .ngpio = 8, \
+ }, \
+ .data_reg = EP93XX_GPIO_REG(dr), \
+ .data_dir_reg = EP93XX_GPIO_REG(ddr), \
+ }
+
+static struct ep93xx_gpio_chip ep93xx_gpio_banks[] = {
+ EP93XX_GPIO_BANK("A", 0x00, 0x10, 0),
+ EP93XX_GPIO_BANK("B", 0x04, 0x14, 8),
+ EP93XX_GPIO_BANK("C", 0x08, 0x18, 40),
+ EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 24),
+ EP93XX_GPIO_BANK("E", 0x20, 0x24, 32),
+ EP93XX_GPIO_BANK("F", 0x30, 0x34, 16),
+ EP93XX_GPIO_BANK("G", 0x38, 0x3c, 48),
+ EP93XX_GPIO_BANK("H", 0x40, 0x44, 56),
+};
+
+void __init ep93xx_gpio_init(void)
+{
+ int i;
+
+ /* Set Ports C, D, E, G, and H for GPIO use */
+ ep93xx_devcfg_set_bits(EP93XX_SYSCON_DEVCFG_KEYS |
+ EP93XX_SYSCON_DEVCFG_GONK |
+ EP93XX_SYSCON_DEVCFG_EONIDE |
+ EP93XX_SYSCON_DEVCFG_GONIDE |
+ EP93XX_SYSCON_DEVCFG_HONIDE);
+
+ for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
+ struct gpio_chip *chip = &ep93xx_gpio_banks[i].chip;
+
+ /*
+ * Ports A, B, and F support input debouncing when
+ * used as interrupts.
+ */
+ if (!strcmp(chip->label, "A") ||
+ !strcmp(chip->label, "B") ||
+ !strcmp(chip->label, "F"))
+ chip->set_debounce = ep93xx_gpio_set_debounce;
+
+ gpiochip_add(chip);
+ }
+}