linuxdebug/drivers/gpio/gpio-104-idio-16.c

346 lines
9.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* GPIO driver for the ACCES 104-IDIO-16 family
* Copyright (C) 2015 William Breathitt Gray
*
* This driver supports the following ACCES devices: 104-IDIO-16,
* 104-IDIO-16E, 104-IDO-16, 104-IDIO-8, 104-IDIO-8E, and 104-IDO-8.
*/
#include <linux/bits.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#define IDIO_16_EXTENT 8
#define MAX_NUM_IDIO_16 max_num_isa_dev(IDIO_16_EXTENT)
static unsigned int base[MAX_NUM_IDIO_16];
static unsigned int num_idio_16;
module_param_hw_array(base, uint, ioport, &num_idio_16, 0);
MODULE_PARM_DESC(base, "ACCES 104-IDIO-16 base addresses");
static unsigned int irq[MAX_NUM_IDIO_16];
static unsigned int num_irq;
module_param_hw_array(irq, uint, irq, &num_irq, 0);
MODULE_PARM_DESC(irq, "ACCES 104-IDIO-16 interrupt line numbers");
/**
* struct idio_16_reg - device registers structure
* @out0_7: Read: N/A
* Write: FET Drive Outputs 0-7
* @in0_7: Read: Isolated Inputs 0-7
* Write: Clear Interrupt
* @irq_ctl: Read: Enable IRQ
* Write: Disable IRQ
* @unused: N/A
* @out8_15: Read: N/A
* Write: FET Drive Outputs 8-15
* @in8_15: Read: Isolated Inputs 8-15
* Write: N/A
*/
struct idio_16_reg {
u8 out0_7;
u8 in0_7;
u8 irq_ctl;
u8 unused;
u8 out8_15;
u8 in8_15;
};
/**
* struct idio_16_gpio - GPIO device private data structure
* @chip: instance of the gpio_chip
* @lock: synchronization lock to prevent I/O race conditions
* @irq_mask: I/O bits affected by interrupts
* @reg: I/O address offset for the device registers
* @out_state: output bits state
*/
struct idio_16_gpio {
struct gpio_chip chip;
raw_spinlock_t lock;
unsigned long irq_mask;
struct idio_16_reg __iomem *reg;
unsigned int out_state;
};
static int idio_16_gpio_get_direction(struct gpio_chip *chip,
unsigned int offset)
{
if (offset > 15)
return GPIO_LINE_DIRECTION_IN;
return GPIO_LINE_DIRECTION_OUT;
}
static int idio_16_gpio_direction_input(struct gpio_chip *chip,
unsigned int offset)
{
return 0;
}
static int idio_16_gpio_direction_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
chip->set(chip, offset, value);
return 0;
}
static int idio_16_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
const unsigned int mask = BIT(offset-16);
if (offset < 16)
return -EINVAL;
if (offset < 24)
return !!(ioread8(&idio16gpio->reg->in0_7) & mask);
return !!(ioread8(&idio16gpio->reg->in8_15) & (mask>>8));
}
static int idio_16_gpio_get_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
*bits = 0;
if (*mask & GENMASK(23, 16))
*bits |= (unsigned long)ioread8(&idio16gpio->reg->in0_7) << 16;
if (*mask & GENMASK(31, 24))
*bits |= (unsigned long)ioread8(&idio16gpio->reg->in8_15) << 24;
return 0;
}
static void idio_16_gpio_set(struct gpio_chip *chip, unsigned int offset,
int value)
{
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
const unsigned int mask = BIT(offset);
unsigned long flags;
if (offset > 15)
return;
raw_spin_lock_irqsave(&idio16gpio->lock, flags);
if (value)
idio16gpio->out_state |= mask;
else
idio16gpio->out_state &= ~mask;
if (offset > 7)
iowrite8(idio16gpio->out_state >> 8, &idio16gpio->reg->out8_15);
else
iowrite8(idio16gpio->out_state, &idio16gpio->reg->out0_7);
raw_spin_unlock_irqrestore(&idio16gpio->lock, flags);
}
static void idio_16_gpio_set_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
unsigned long flags;
raw_spin_lock_irqsave(&idio16gpio->lock, flags);
idio16gpio->out_state &= ~*mask;
idio16gpio->out_state |= *mask & *bits;
if (*mask & 0xFF)
iowrite8(idio16gpio->out_state, &idio16gpio->reg->out0_7);
if ((*mask >> 8) & 0xFF)
iowrite8(idio16gpio->out_state >> 8, &idio16gpio->reg->out8_15);
raw_spin_unlock_irqrestore(&idio16gpio->lock, flags);
}
static void idio_16_irq_ack(struct irq_data *data)
{
}
static void idio_16_irq_mask(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
const unsigned long offset = irqd_to_hwirq(data);
unsigned long flags;
idio16gpio->irq_mask &= ~BIT(offset);
gpiochip_disable_irq(chip, offset);
if (!idio16gpio->irq_mask) {
raw_spin_lock_irqsave(&idio16gpio->lock, flags);
iowrite8(0, &idio16gpio->reg->irq_ctl);
raw_spin_unlock_irqrestore(&idio16gpio->lock, flags);
}
}
static void idio_16_irq_unmask(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(chip);
const unsigned long offset = irqd_to_hwirq(data);
const unsigned long prev_irq_mask = idio16gpio->irq_mask;
unsigned long flags;
gpiochip_enable_irq(chip, offset);
idio16gpio->irq_mask |= BIT(offset);
if (!prev_irq_mask) {
raw_spin_lock_irqsave(&idio16gpio->lock, flags);
ioread8(&idio16gpio->reg->irq_ctl);
raw_spin_unlock_irqrestore(&idio16gpio->lock, flags);
}
}
static int idio_16_irq_set_type(struct irq_data *data, unsigned int flow_type)
{
/* The only valid irq types are none and both-edges */
if (flow_type != IRQ_TYPE_NONE &&
(flow_type & IRQ_TYPE_EDGE_BOTH) != IRQ_TYPE_EDGE_BOTH)
return -EINVAL;
return 0;
}
static const struct irq_chip idio_16_irqchip = {
.name = "104-idio-16",
.irq_ack = idio_16_irq_ack,
.irq_mask = idio_16_irq_mask,
.irq_unmask = idio_16_irq_unmask,
.irq_set_type = idio_16_irq_set_type,
.flags = IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static irqreturn_t idio_16_irq_handler(int irq, void *dev_id)
{
struct idio_16_gpio *const idio16gpio = dev_id;
struct gpio_chip *const chip = &idio16gpio->chip;
int gpio;
for_each_set_bit(gpio, &idio16gpio->irq_mask, chip->ngpio)
generic_handle_domain_irq(chip->irq.domain, gpio);
raw_spin_lock(&idio16gpio->lock);
iowrite8(0, &idio16gpio->reg->in0_7);
raw_spin_unlock(&idio16gpio->lock);
return IRQ_HANDLED;
}
#define IDIO_16_NGPIO 32
static const char *idio_16_names[IDIO_16_NGPIO] = {
"OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7",
"OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15",
"IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7",
"IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15"
};
static int idio_16_irq_init_hw(struct gpio_chip *gc)
{
struct idio_16_gpio *const idio16gpio = gpiochip_get_data(gc);
/* Disable IRQ by default */
iowrite8(0, &idio16gpio->reg->irq_ctl);
iowrite8(0, &idio16gpio->reg->in0_7);
return 0;
}
static int idio_16_probe(struct device *dev, unsigned int id)
{
struct idio_16_gpio *idio16gpio;
const char *const name = dev_name(dev);
struct gpio_irq_chip *girq;
int err;
idio16gpio = devm_kzalloc(dev, sizeof(*idio16gpio), GFP_KERNEL);
if (!idio16gpio)
return -ENOMEM;
if (!devm_request_region(dev, base[id], IDIO_16_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
base[id], base[id] + IDIO_16_EXTENT);
return -EBUSY;
}
idio16gpio->reg = devm_ioport_map(dev, base[id], IDIO_16_EXTENT);
if (!idio16gpio->reg)
return -ENOMEM;
idio16gpio->chip.label = name;
idio16gpio->chip.parent = dev;
idio16gpio->chip.owner = THIS_MODULE;
idio16gpio->chip.base = -1;
idio16gpio->chip.ngpio = IDIO_16_NGPIO;
idio16gpio->chip.names = idio_16_names;
idio16gpio->chip.get_direction = idio_16_gpio_get_direction;
idio16gpio->chip.direction_input = idio_16_gpio_direction_input;
idio16gpio->chip.direction_output = idio_16_gpio_direction_output;
idio16gpio->chip.get = idio_16_gpio_get;
idio16gpio->chip.get_multiple = idio_16_gpio_get_multiple;
idio16gpio->chip.set = idio_16_gpio_set;
idio16gpio->chip.set_multiple = idio_16_gpio_set_multiple;
idio16gpio->out_state = 0xFFFF;
girq = &idio16gpio->chip.irq;
gpio_irq_chip_set_chip(girq, &idio_16_irqchip);
/* This will let us handle the parent IRQ in the driver */
girq->parent_handler = NULL;
girq->num_parents = 0;
girq->parents = NULL;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_edge_irq;
girq->init_hw = idio_16_irq_init_hw;
raw_spin_lock_init(&idio16gpio->lock);
err = devm_gpiochip_add_data(dev, &idio16gpio->chip, idio16gpio);
if (err) {
dev_err(dev, "GPIO registering failed (%d)\n", err);
return err;
}
err = devm_request_irq(dev, irq[id], idio_16_irq_handler, 0, name,
idio16gpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
return err;
}
return 0;
}
static struct isa_driver idio_16_driver = {
.probe = idio_16_probe,
.driver = {
.name = "104-idio-16"
},
};
module_isa_driver_with_irq(idio_16_driver, num_idio_16, num_irq);
MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
MODULE_DESCRIPTION("ACCES 104-IDIO-16 GPIO driver");
MODULE_LICENSE("GPL v2");