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Diffstat (limited to 'arch/arm/mach-ep93xx/gpio.c')
-rw-r--r--arch/arm/mach-ep93xx/gpio.c235
1 files changed, 231 insertions, 4 deletions
diff --git a/arch/arm/mach-ep93xx/gpio.c b/arch/arm/mach-ep93xx/gpio.c
index 1ea8871e03a9..cc377ae8c428 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);
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