// SPDX-License-Identifier: GPL-2.0-only
/*
* GPIO driver for the ACCES 104-DIO-48E series
* Copyright (C) 2016 William Breathitt Gray
*
* This driver supports the following ACCES devices: 104-DIO-48E and
* 104-DIO-24E.
*/
#include <linux/bits.h>
#include <linux/device.h>
#include <linux/err.h>
#include <linux/i8254.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/isa.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/regmap.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include "gpio-i8255.h"
MODULE_IMPORT_NS(I8255);
#define DIO48E_EXTENT 16
#define MAX_NUM_DIO48E max_num_isa_dev(DIO48E_EXTENT)
static unsigned int base[MAX_NUM_DIO48E];
static unsigned int num_dio48e;
module_param_hw_array(base, uint, ioport, &num_dio48e, 0);
MODULE_PARM_DESC(base, "ACCES 104-DIO-48E base addresses");
static unsigned int irq[MAX_NUM_DIO48E];
static unsigned int num_irq;
module_param_hw_array(irq, uint, irq, &num_irq, 0);
MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers");
#define DIO48E_ENABLE_INTERRUPT 0xB
#define DIO48E_DISABLE_INTERRUPT DIO48E_ENABLE_INTERRUPT
#define DIO48E_ENABLE_COUNTER_TIMER_ADDRESSING 0xD
#define DIO48E_DISABLE_COUNTER_TIMER_ADDRESSING DIO48E_ENABLE_COUNTER_TIMER_ADDRESSING
#define DIO48E_CLEAR_INTERRUPT 0xF
#define DIO48E_NUM_PPI 2
static const struct regmap_range dio48e_wr_ranges[] = {
regmap_reg_range(0x0, 0x9), regmap_reg_range(0xB, 0xB),
regmap_reg_range(0xD, 0xD), regmap_reg_range(0xF, 0xF),
};
static const struct regmap_range dio48e_rd_ranges[] = {
regmap_reg_range(0x0, 0x2), regmap_reg_range(0x4, 0x6),
regmap_reg_range(0xB, 0xB), regmap_reg_range(0xD, 0xD),
regmap_reg_range(0xF, 0xF),
};
static const struct regmap_range dio48e_volatile_ranges[] = {
i8255_volatile_regmap_range(0x0), i8255_volatile_regmap_range(0x4),
regmap_reg_range(0xB, 0xB), regmap_reg_range(0xD, 0xD),
regmap_reg_range(0xF, 0xF),
};
static const struct regmap_range dio48e_precious_ranges[] = {
regmap_reg_range(0xB, 0xB), regmap_reg_range(0xD, 0xD),
regmap_reg_range(0xF, 0xF),
};
static const struct regmap_access_table dio48e_wr_table = {
.yes_ranges = dio48e_wr_ranges,
.n_yes_ranges = ARRAY_SIZE(dio48e_wr_ranges),
};
static const struct regmap_access_table dio48e_rd_table = {
.yes_ranges = dio48e_rd_ranges,
.n_yes_ranges = ARRAY_SIZE(dio48e_rd_ranges),
};
static const struct regmap_access_table dio48e_volatile_table = {
.yes_ranges = dio48e_volatile_ranges,
.n_yes_ranges = ARRAY_SIZE(dio48e_volatile_ranges),
};
static const struct regmap_access_table dio48e_precious_table = {
.yes_ranges = dio48e_precious_ranges,
.n_yes_ranges = ARRAY_SIZE(dio48e_precious_ranges),
};
static const struct regmap_range pit_wr_ranges[] = {
regmap_reg_range(0x0, 0x3),
};
static const struct regmap_range pit_rd_ranges[] = {
regmap_reg_range(0x0, 0x2),
};
static const struct regmap_access_table pit_wr_table = {
.yes_ranges = pit_wr_ranges,
.n_yes_ranges = ARRAY_SIZE(pit_wr_ranges),
};
static const struct regmap_access_table pit_rd_table = {
.yes_ranges = pit_rd_ranges,
.n_yes_ranges = ARRAY_SIZE(pit_rd_ranges),
};
/* only bit 3 on each respective Port C supports interrupts */
#define DIO48E_REGMAP_IRQ(_ppi) \
[19 + (_ppi) * 24] = { \
.mask = BIT(_ppi), \
.type = { .types_supported = IRQ_TYPE_EDGE_RISING }, \
}
static const struct regmap_irq dio48e_regmap_irqs[] = {
DIO48E_REGMAP_IRQ(0), DIO48E_REGMAP_IRQ(1),
};
/**
* struct dio48e_gpio - GPIO device private data structure
* @lock: synchronization lock to prevent I/O race conditions
* @map: Regmap for the device
* @regs: virtual mapping for device registers
* @flags: IRQ flags saved during locking
* @irq_mask: Current IRQ mask state on the device
*/
struct dio48e_gpio {
raw_spinlock_t lock;
struct regmap *map;
void __iomem *regs;
unsigned long flags;
unsigned int irq_mask;
};
static void dio48e_regmap_lock(void *lock_arg) __acquires(&dio48egpio->lock)
{
struct dio48e_gpio *const dio48egpio = lock_arg;
unsigned long flags;
raw_spin_lock_irqsave(&dio48egpio->lock, flags);
dio48egpio->flags = flags;
}
static void dio48e_regmap_unlock(void *lock_arg) __releases(&dio48egpio->lock)
{
struct dio48e_gpio *const dio48egpio = lock_arg;
raw_spin_unlock_irqrestore(&dio48egpio->lock, dio48egpio->flags);
}
static void pit_regmap_lock(void *lock_arg) __acquires(&dio48egpio->lock)
{
struct dio48e_gpio *const dio48egpio = lock_arg;
unsigned long flags;
raw_spin_lock_irqsave(&dio48egpio->lock, flags);
dio48egpio->flags = flags;
iowrite8(0x00, dio48egpio->regs + DIO48E_ENABLE_COUNTER_TIMER_ADDRESSING);
}
static void pit_regmap_unlock(void *lock_arg) __releases(&dio48egpio->lock)
{
struct dio48e_gpio *const dio48egpio = lock_arg;
ioread8(dio48egpio->regs + DIO48E_DISABLE_COUNTER_TIMER_ADDRESSING);
raw_spin_unlock_irqrestore(&dio48egpio->lock, dio48egpio->flags);
}
static int dio48e_handle_mask_sync(const int index,
const unsigned int mask_buf_def,
const unsigned int mask_buf,
void *const irq_drv_data)
{
struct dio48e_gpio *const dio48egpio = irq_drv_data;
const unsigned int prev_mask = dio48egpio->irq_mask;
int err;
unsigned int val;
/* exit early if no change since the previous mask */
if (mask_buf == prev_mask)
return 0;
/* remember the current mask for the next mask sync */
dio48egpio->irq_mask = mask_buf;
/* if all previously masked, enable interrupts when unmasking */
if (prev_mask == mask_buf_def) {
err = regmap_write(dio48egpio->map, DIO48E_CLEAR_INTERRUPT, 0x00);
if (err)
return err;
return regmap_write(dio48egpio->map, DIO48E_ENABLE_INTERRUPT, 0x00);
}
/* if all are currently masked, disable interrupts */
if (mask_buf == mask_buf_def)
return regmap_read(dio48egpio->map, DIO48E_DISABLE_INTERRUPT, &val);
return 0;
}
#define DIO48E_NGPIO 48
static const char *dio48e_names[DIO48E_NGPIO] = {
"PPI Group 0 Port A 0", "PPI Group 0 Port A 1", "PPI Group 0 Port A 2",
"PPI Group 0 Port A 3", "PPI Group 0 Port A 4", "PPI Group 0 Port A 5",
"PPI Group 0 Port A 6", "PPI Group 0 Port A 7", "PPI Group 0 Port B 0",
"PPI Group 0 Port B 1", "PPI Group 0 Port B 2", "PPI Group 0 Port B 3",
"PPI Group 0 Port B 4", "PPI Group 0 Port B 5", "PPI Group 0 Port B 6",
"PPI Group 0 Port B 7", "PPI Group 0 Port C 0", "PPI Group 0 Port C 1",
"PPI Group 0 Port C 2", "PPI Group 0 Port C 3", "PPI Group 0 Port C 4",
"PPI Group 0 Port C 5", "PPI Group 0 Port C 6", "PPI Group 0 Port C 7",
"PPI Group 1 Port A 0", "PPI Group 1 Port A 1", "PPI Group 1 Port A 2",
"PPI Group 1 Port A 3", "PPI Group 1 Port A 4", "PPI Group 1 Port A 5",
"PPI Group 1 Port A 6", "PPI Group 1 Port A 7", "PPI Group 1 Port B 0",
"PPI Group 1 Port B 1", "PPI Group 1 Port B 2", "PPI Group 1 Port B 3",
"PPI Group 1 Port B 4", "PPI Group 1 Port B 5", "PPI Group 1 Port B 6",
"PPI Group 1 Port B 7", "PPI Group 1 Port C 0", "PPI Group 1 Port C 1",
"PPI Group 1 Port C 2", "PPI Group 1 Port C 3", "PPI Group 1 Port C 4",
"PPI Group 1 Port C 5", "PPI Group 1 Port C 6", "PPI Group 1 Port C 7"
};
static int dio48e_irq_init_hw(struct regmap *const map)
{
unsigned int val;
/* Disable IRQ by default */
return regmap_read(map, DIO48E_DISABLE_INTERRUPT, &val);
}
static int dio48e_probe(struct device *dev, unsigned int id)
{
const char *const name = dev_name(dev);
struct i8255_regmap_config config = {};
void __iomem *regs;
struct regmap *map;
struct regmap_config dio48e_regmap_config;
struct regmap_config pit_regmap_config;
struct i8254_regmap_config pit_config;
int err;
struct regmap_irq_chip *chip;
struct dio48e_gpio *dio48egpio;
struct regmap_irq_chip_data *chip_data;
if (!devm_request_region(dev, base[id], DIO48E_EXTENT, name)) {
dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
base[id], base[id] + DIO48E_EXTENT);
return -EBUSY;
}
dio48egpio = devm_kzalloc(dev, sizeof(*dio48egpio), GFP_KERNEL);
if (!dio48egpio)
return -ENOMEM;
regs = devm_ioport_map(dev, base[id], DIO48E_EXTENT);
if (!regs)
return -ENOMEM;
dio48egpio->regs = regs;
raw_spin_lock_init(&dio48egpio->lock);
dio48e_regmap_config = (struct regmap_config) {
.reg_bits = 8,
.reg_stride = 1,
.val_bits = 8,
.lock = dio48e_regmap_lock,
.unlock = dio48e_regmap_unlock,
.lock_arg = dio48egpio,
.io_port = true,
.wr_table = &dio48e_wr_table,
.rd_table = &dio48e_rd_table,
.volatile_table = &dio48e_volatile_table,
.precious_table = &dio48e_precious_table,
.cache_type = REGCACHE_FLAT,
};
map = devm_regmap_init_mmio(dev, regs, &dio48e_regmap_config);
if (IS_ERR(map))
return dev_err_probe(dev, PTR_ERR(map),
"Unable to initialize register map\n");
dio48egpio->map = map;
pit_regmap_config = (struct regmap_config) {
.name = "i8254",
.reg_bits = 8,
.reg_stride = 1,
.val_bits = 8,
.lock = pit_regmap_lock,
.unlock = pit_regmap_unlock,
.lock_arg = dio48egpio,
.io_port = true,
.wr_table = &pit_wr_table,
.rd_table = &pit_rd_table,
};
pit_config.map = devm_regmap_init_mmio(dev, regs, &pit_regmap_config);
if (IS_ERR(pit_config.map))
return dev_err_probe(dev, PTR_ERR(pit_config.map),
"Unable to initialize i8254 register map\n");
chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->name = name;
chip->mask_base = DIO48E_ENABLE_INTERRUPT;
chip->ack_base = DIO48E_CLEAR_INTERRUPT;
chip->no_status = true;
chip->num_regs = 1;
chip->irqs = dio48e_regmap_irqs;
chip->num_irqs = ARRAY_SIZE(dio48e_regmap_irqs);
chip->handle_mask_sync = dio48e_handle_mask_sync;
chip->irq_drv_data = dio48egpio;
/* Initialize to prevent spurious interrupts before we're ready */
err = dio48e_irq_init_hw(map);
if (err)
return err;
err = devm_regmap_add_irq_chip(dev, map, irq[id], 0, 0, chip, &chip_data);
if (err)
return dev_err_probe(dev, err, "IRQ registration failed\n");
pit_config.parent = dev;
err = devm_i8254_regmap_register(dev, &pit_config);
if (err)
return err;
config.parent = dev;
config.map = map;
config.num_ppi = DIO48E_NUM_PPI;
config.names = dio48e_names;
config.domain = regmap_irq_get_domain(chip_data);
return devm_i8255_regmap_register(dev, &config);
}
static struct isa_driver dio48e_driver = {
.probe = dio48e_probe,
.driver = {
.name = "104-dio-48e"
},
};
module_isa_driver_with_irq(dio48e_driver, num_dio48e, num_irq);
MODULE_AUTHOR("William Breathitt Gray <[email protected]>");
MODULE_DESCRIPTION("ACCES 104-DIO-48E GPIO driver");
MODULE_LICENSE("GPL v2");
MODULE_IMPORT_NS(I8254);
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