// SPDX-License-Identifier: GPL-2.0
/*
* Generic EP93xx GPIO handling
*
* Copyright (c) 2008 Ryan Mallon
* Copyright (c) 2011 H Hartley Sweeten <[email protected]>
*
* Based on code originally from:
* linux/arch/arm/mach-ep93xx/core.c
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/slab.h>
#include <linux/gpio/driver.h>
#include <linux/bitops.h>
#include <linux/seq_file.h>
#define EP93XX_GPIO_F_INT_STATUS 0x5c
#define EP93XX_GPIO_A_INT_STATUS 0xa0
#define EP93XX_GPIO_B_INT_STATUS 0xbc
/* Maximum value for gpio line identifiers */
#define EP93XX_GPIO_LINE_MAX 63
/* Number of GPIO chips in EP93XX */
#define EP93XX_GPIO_CHIP_NUM 8
/* Maximum value for irq capable line identifiers */
#define EP93XX_GPIO_LINE_MAX_IRQ 23
#define EP93XX_GPIO_A_IRQ_BASE 64
#define EP93XX_GPIO_B_IRQ_BASE 72
/*
* Static mapping of GPIO bank F IRQS:
* F0..F7 (16..24) to irq 80..87.
*/
#define EP93XX_GPIO_F_IRQ_BASE 80
struct ep93xx_gpio_irq_chip {
u8 irq_offset;
u8 int_unmasked;
u8 int_enabled;
u8 int_type1;
u8 int_type2;
u8 int_debounce;
};
struct ep93xx_gpio_chip {
struct gpio_chip gc;
struct ep93xx_gpio_irq_chip *eic;
};
struct ep93xx_gpio {
void __iomem *base;
struct ep93xx_gpio_chip gc[EP93XX_GPIO_CHIP_NUM];
};
#define to_ep93xx_gpio_chip(x) container_of(x, struct ep93xx_gpio_chip, gc)
static struct ep93xx_gpio_irq_chip *to_ep93xx_gpio_irq_chip(struct gpio_chip *gc)
{
struct ep93xx_gpio_chip *egc = to_ep93xx_gpio_chip(gc);
return egc->eic;
}
/*************************************************************************
* Interrupt handling for EP93xx on-chip GPIOs
*************************************************************************/
#define EP93XX_INT_TYPE1_OFFSET 0x00
#define EP93XX_INT_TYPE2_OFFSET 0x04
#define EP93XX_INT_EOI_OFFSET 0x08
#define EP93XX_INT_EN_OFFSET 0x0c
#define EP93XX_INT_STATUS_OFFSET 0x10
#define EP93XX_INT_RAW_STATUS_OFFSET 0x14
#define EP93XX_INT_DEBOUNCE_OFFSET 0x18
static void ep93xx_gpio_update_int_params(struct ep93xx_gpio *epg,
struct ep93xx_gpio_irq_chip *eic)
{
writeb_relaxed(0, epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET);
writeb_relaxed(eic->int_type2,
epg->base + eic->irq_offset + EP93XX_INT_TYPE2_OFFSET);
writeb_relaxed(eic->int_type1,
epg->base + eic->irq_offset + EP93XX_INT_TYPE1_OFFSET);
writeb_relaxed(eic->int_unmasked & eic->int_enabled,
epg->base + eic->irq_offset + EP93XX_INT_EN_OFFSET);
}
static void ep93xx_gpio_int_debounce(struct gpio_chip *gc,
unsigned int offset, bool enable)
{
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
int port_mask = BIT(offset);
if (enable)
eic->int_debounce |= port_mask;
else
eic->int_debounce &= ~port_mask;
writeb(eic->int_debounce,
epg->base + eic->irq_offset + EP93XX_INT_DEBOUNCE_OFFSET);
}
static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc)
{
struct gpio_chip *gc = irq_desc_get_handler_data(desc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
struct irq_chip *irqchip = irq_desc_get_chip(desc);
unsigned long stat;
int offset;
chained_irq_enter(irqchip, desc);
/*
* Dispatch the IRQs to the irqdomain of each A and B
* gpiochip irqdomains depending on what has fired.
* The tricky part is that the IRQ line is shared
* between bank A and B and each has their own gpiochip.
*/
stat = readb(epg->base + EP93XX_GPIO_A_INT_STATUS);
for_each_set_bit(offset, &stat, 8)
generic_handle_domain_irq(epg->gc[0].gc.irq.domain,
offset);
stat = readb(epg->base + EP93XX_GPIO_B_INT_STATUS);
for_each_set_bit(offset, &stat, 8)
generic_handle_domain_irq(epg->gc[1].gc.irq.domain,
offset);
chained_irq_exit(irqchip, desc);
}
static void ep93xx_gpio_f_irq_handler(struct irq_desc *desc)
{
/*
* map discontiguous hw irq range to continuous sw irq range:
*
* IRQ_EP93XX_GPIO{0..7}MUX -> EP93XX_GPIO_LINE_F{0..7}
*/
struct irq_chip *irqchip = irq_desc_get_chip(desc);
unsigned int irq = irq_desc_get_irq(desc);
int port_f_idx = (irq & 7) ^ 4; /* {20..23,48..51} -> {0..7} */
int gpio_irq = EP93XX_GPIO_F_IRQ_BASE + port_f_idx;
chained_irq_enter(irqchip, desc);
generic_handle_irq(gpio_irq);
chained_irq_exit(irqchip, desc);
}
static void ep93xx_gpio_irq_ack(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
int port_mask = BIT(d->irq & 7);
if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH) {
eic->int_type2 ^= port_mask; /* switch edge direction */
ep93xx_gpio_update_int_params(epg, eic);
}
writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
}
static void ep93xx_gpio_irq_mask_ack(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
int port_mask = BIT(d->irq & 7);
if (irqd_get_trigger_type(d) == IRQ_TYPE_EDGE_BOTH)
eic->int_type2 ^= port_mask; /* switch edge direction */
eic->int_unmasked &= ~port_mask;
ep93xx_gpio_update_int_params(epg, eic);
writeb(port_mask, epg->base + eic->irq_offset + EP93XX_INT_EOI_OFFSET);
gpiochip_disable_irq(gc, irqd_to_hwirq(d));
}
static void ep93xx_gpio_irq_mask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
eic->int_unmasked &= ~BIT(d->irq & 7);
ep93xx_gpio_update_int_params(epg, eic);
gpiochip_disable_irq(gc, irqd_to_hwirq(d));
}
static void ep93xx_gpio_irq_unmask(struct irq_data *d)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
gpiochip_enable_irq(gc, irqd_to_hwirq(d));
eic->int_unmasked |= BIT(d->irq & 7);
ep93xx_gpio_update_int_params(epg, eic);
}
/*
* 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)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
struct ep93xx_gpio *epg = gpiochip_get_data(gc);
int offset = d->irq & 7;
int port_mask = BIT(offset);
irq_flow_handler_t handler;
gc->direction_input(gc, offset);
switch (type) {
case IRQ_TYPE_EDGE_RISING:
eic->int_type1 |= port_mask;
eic->int_type2 |= port_mask;
handler = handle_edge_irq;
break;
case IRQ_TYPE_EDGE_FALLING:
eic->int_type1 |= port_mask;
eic->int_type2 &= ~port_mask;
handler = handle_edge_irq;
break;
case IRQ_TYPE_LEVEL_HIGH:
eic->int_type1 &= ~port_mask;
eic->int_type2 |= port_mask;
handler = handle_level_irq;
break;
case IRQ_TYPE_LEVEL_LOW:
eic->int_type1 &= ~port_mask;
eic->int_type2 &= ~port_mask;
handler = handle_level_irq;
break;
case IRQ_TYPE_EDGE_BOTH:
eic->int_type1 |= port_mask;
/* set initial polarity based on current input level */
if (gc->get(gc, offset))
eic->int_type2 &= ~port_mask; /* falling */
else
eic->int_type2 |= port_mask; /* rising */
handler = handle_edge_irq;
break;
default:
return -EINVAL;
}
irq_set_handler_locked(d, handler);
eic->int_enabled |= port_mask;
ep93xx_gpio_update_int_params(epg, eic);
return 0;
}
/*************************************************************************
* gpiolib interface for EP93xx on-chip GPIOs
*************************************************************************/
struct ep93xx_gpio_bank {
const char *label;
int data;
int dir;
int irq;
int base;
bool has_irq;
bool has_hierarchical_irq;
unsigned int irq_base;
};
#define EP93XX_GPIO_BANK(_label, _data, _dir, _irq, _base, _has_irq, _has_hier, _irq_base) \
{ \
.label = _label, \
.data = _data, \
.dir = _dir, \
.irq = _irq, \
.base = _base, \
.has_irq = _has_irq, \
.has_hierarchical_irq = _has_hier, \
.irq_base = _irq_base, \
}
static struct ep93xx_gpio_bank ep93xx_gpio_banks[] = {
/* Bank A has 8 IRQs */
EP93XX_GPIO_BANK("A", 0x00, 0x10, 0x90, 0, true, false, EP93XX_GPIO_A_IRQ_BASE),
/* Bank B has 8 IRQs */
EP93XX_GPIO_BANK("B", 0x04, 0x14, 0xac, 8, true, false, EP93XX_GPIO_B_IRQ_BASE),
EP93XX_GPIO_BANK("C", 0x08, 0x18, 0x00, 40, false, false, 0),
EP93XX_GPIO_BANK("D", 0x0c, 0x1c, 0x00, 24, false, false, 0),
EP93XX_GPIO_BANK("E", 0x20, 0x24, 0x00, 32, false, false, 0),
/* Bank F has 8 IRQs */
EP93XX_GPIO_BANK("F", 0x30, 0x34, 0x4c, 16, false, true, EP93XX_GPIO_F_IRQ_BASE),
EP93XX_GPIO_BANK("G", 0x38, 0x3c, 0x00, 48, false, false, 0),
EP93XX_GPIO_BANK("H", 0x40, 0x44, 0x00, 56, false, false, 0),
};
static int ep93xx_gpio_set_config(struct gpio_chip *gc, unsigned offset,
unsigned long config)
{
u32 debounce;
if (pinconf_to_config_param(config) != PIN_CONFIG_INPUT_DEBOUNCE)
return -ENOTSUPP;
debounce = pinconf_to_config_argument(config);
ep93xx_gpio_int_debounce(gc, offset, debounce ? true : false);
return 0;
}
static void ep93xx_irq_print_chip(struct irq_data *data, struct seq_file *p)
{
struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
seq_printf(p, dev_name(gc->parent));
}
static const struct irq_chip gpio_eic_irq_chip = {
.name = "ep93xx-gpio-eic",
.irq_ack = ep93xx_gpio_irq_ack,
.irq_mask = ep93xx_gpio_irq_mask,
.irq_unmask = ep93xx_gpio_irq_unmask,
.irq_mask_ack = ep93xx_gpio_irq_mask_ack,
.irq_set_type = ep93xx_gpio_irq_type,
.irq_print_chip = ep93xx_irq_print_chip,
.flags = IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static int ep93xx_gpio_add_bank(struct ep93xx_gpio_chip *egc,
struct platform_device *pdev,
struct ep93xx_gpio *epg,
struct ep93xx_gpio_bank *bank)
{
void __iomem *data = epg->base + bank->data;
void __iomem *dir = epg->base + bank->dir;
struct gpio_chip *gc = &egc->gc;
struct device *dev = &pdev->dev;
struct gpio_irq_chip *girq;
int err;
err = bgpio_init(gc, dev, 1, data, NULL, NULL, dir, NULL, 0);
if (err)
return err;
gc->label = bank->label;
gc->base = bank->base;
girq = &gc->irq;
if (bank->has_irq || bank->has_hierarchical_irq) {
gc->set_config = ep93xx_gpio_set_config;
egc->eic = devm_kcalloc(dev, 1,
sizeof(*egc->eic),
GFP_KERNEL);
if (!egc->eic)
return -ENOMEM;
egc->eic->irq_offset = bank->irq;
gpio_irq_chip_set_chip(girq, &gpio_eic_irq_chip);
}
if (bank->has_irq) {
int ab_parent_irq = platform_get_irq(pdev, 0);
girq->parent_handler = ep93xx_gpio_ab_irq_handler;
girq->num_parents = 1;
girq->parents = devm_kcalloc(dev, girq->num_parents,
sizeof(*girq->parents),
GFP_KERNEL);
if (!girq->parents)
return -ENOMEM;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_level_irq;
girq->parents[0] = ab_parent_irq;
girq->first = bank->irq_base;
}
/* Only bank F has especially funky IRQ handling */
if (bank->has_hierarchical_irq) {
int gpio_irq;
int i;
/*
* FIXME: convert this to use hierarchical IRQ support!
* this requires fixing the root irqchip to be hierarchical.
*/
girq->parent_handler = ep93xx_gpio_f_irq_handler;
girq->num_parents = 8;
girq->parents = devm_kcalloc(dev, girq->num_parents,
sizeof(*girq->parents),
GFP_KERNEL);
if (!girq->parents)
return -ENOMEM;
/* Pick resources 1..8 for these IRQs */
for (i = 0; i < girq->num_parents; i++) {
girq->parents[i] = platform_get_irq(pdev, i + 1);
gpio_irq = bank->irq_base + i;
irq_set_chip_data(gpio_irq, &epg->gc[5]);
irq_set_chip_and_handler(gpio_irq,
girq->chip,
handle_level_irq);
irq_clear_status_flags(gpio_irq, IRQ_NOREQUEST);
}
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_level_irq;
girq->first = bank->irq_base;
}
return devm_gpiochip_add_data(dev, gc, epg);
}
static int ep93xx_gpio_probe(struct platform_device *pdev)
{
struct ep93xx_gpio *epg;
int i;
epg = devm_kzalloc(&pdev->dev, sizeof(*epg), GFP_KERNEL);
if (!epg)
return -ENOMEM;
epg->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(epg->base))
return PTR_ERR(epg->base);
for (i = 0; i < ARRAY_SIZE(ep93xx_gpio_banks); i++) {
struct ep93xx_gpio_chip *gc = &epg->gc[i];
struct ep93xx_gpio_bank *bank = &ep93xx_gpio_banks[i];
if (ep93xx_gpio_add_bank(gc, pdev, epg, bank))
dev_warn(&pdev->dev, "Unable to add gpio bank %s\n",
bank->label);
}
return 0;
}
static struct platform_driver ep93xx_gpio_driver = {
.driver = {
.name = "gpio-ep93xx",
},
.probe = ep93xx_gpio_probe,
};
static int __init ep93xx_gpio_init(void)
{
return platform_driver_register(&ep93xx_gpio_driver);
}
postcore_initcall(ep93xx_gpio_init);
MODULE_AUTHOR("Ryan Mallon <[email protected]> "
"H Hartley Sweeten <[email protected]>");
MODULE_DESCRIPTION("EP93XX GPIO driver");
MODULE_LICENSE("GPL");
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