https://github.com/torvalds/linux
Tip revision: 92bf22614b21a2706f4993b278017e437f7785b3 authored by Linus Torvalds on 07 February 2021, 21:57:38 UTC
Linux 5.11-rc7
Linux 5.11-rc7
Tip revision: 92bf226
gpio-pcie-idio-24.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* GPIO driver for the ACCES PCIe-IDIO-24 family
* Copyright (C) 2018 William Breathitt Gray
*
* 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.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* This driver supports the following ACCES devices: PCIe-IDIO-24,
* PCIe-IDI-24, PCIe-IDO-24, and PCIe-IDIO-12.
*/
#include <linux/bitmap.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/irqdesc.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/spinlock.h>
#include <linux/types.h>
/*
* PLX PEX8311 PCI LCS_INTCSR Interrupt Control/Status
*
* Bit: Description
* 0: Enable Interrupt Sources (Bit 0)
* 1: Enable Interrupt Sources (Bit 1)
* 2: Generate Internal PCI Bus Internal SERR# Interrupt
* 3: Mailbox Interrupt Enable
* 4: Power Management Interrupt Enable
* 5: Power Management Interrupt
* 6: Slave Read Local Data Parity Check Error Enable
* 7: Slave Read Local Data Parity Check Error Status
* 8: Internal PCI Wire Interrupt Enable
* 9: PCI Express Doorbell Interrupt Enable
* 10: PCI Abort Interrupt Enable
* 11: Local Interrupt Input Enable
* 12: Retry Abort Enable
* 13: PCI Express Doorbell Interrupt Active
* 14: PCI Abort Interrupt Active
* 15: Local Interrupt Input Active
* 16: Local Interrupt Output Enable
* 17: Local Doorbell Interrupt Enable
* 18: DMA Channel 0 Interrupt Enable
* 19: DMA Channel 1 Interrupt Enable
* 20: Local Doorbell Interrupt Active
* 21: DMA Channel 0 Interrupt Active
* 22: DMA Channel 1 Interrupt Active
* 23: Built-In Self-Test (BIST) Interrupt Active
* 24: Direct Master was the Bus Master during a Master or Target Abort
* 25: DMA Channel 0 was the Bus Master during a Master or Target Abort
* 26: DMA Channel 1 was the Bus Master during a Master or Target Abort
* 27: Target Abort after internal 256 consecutive Master Retrys
* 28: PCI Bus wrote data to LCS_MBOX0
* 29: PCI Bus wrote data to LCS_MBOX1
* 30: PCI Bus wrote data to LCS_MBOX2
* 31: PCI Bus wrote data to LCS_MBOX3
*/
#define PLX_PEX8311_PCI_LCS_INTCSR 0x68
#define INTCSR_INTERNAL_PCI_WIRE BIT(8)
#define INTCSR_LOCAL_INPUT BIT(11)
/**
* struct idio_24_gpio_reg - GPIO device registers structure
* @out0_7: Read: FET Outputs 0-7
* Write: FET Outputs 0-7
* @out8_15: Read: FET Outputs 8-15
* Write: FET Outputs 8-15
* @out16_23: Read: FET Outputs 16-23
* Write: FET Outputs 16-23
* @ttl_out0_7: Read: TTL/CMOS Outputs 0-7
* Write: TTL/CMOS Outputs 0-7
* @in0_7: Read: Isolated Inputs 0-7
* Write: Reserved
* @in8_15: Read: Isolated Inputs 8-15
* Write: Reserved
* @in16_23: Read: Isolated Inputs 16-23
* Write: Reserved
* @ttl_in0_7: Read: TTL/CMOS Inputs 0-7
* Write: Reserved
* @cos0_7: Read: COS Status Inputs 0-7
* Write: COS Clear Inputs 0-7
* @cos8_15: Read: COS Status Inputs 8-15
* Write: COS Clear Inputs 8-15
* @cos16_23: Read: COS Status Inputs 16-23
* Write: COS Clear Inputs 16-23
* @cos_ttl0_7: Read: COS Status TTL/CMOS 0-7
* Write: COS Clear TTL/CMOS 0-7
* @ctl: Read: Control Register
* Write: Control Register
* @reserved: Read: Reserved
* Write: Reserved
* @cos_enable: Read: COS Enable
* Write: COS Enable
* @soft_reset: Read: IRQ Output Pin Status
* Write: Software Board Reset
*/
struct idio_24_gpio_reg {
u8 out0_7;
u8 out8_15;
u8 out16_23;
u8 ttl_out0_7;
u8 in0_7;
u8 in8_15;
u8 in16_23;
u8 ttl_in0_7;
u8 cos0_7;
u8 cos8_15;
u8 cos16_23;
u8 cos_ttl0_7;
u8 ctl;
u8 reserved;
u8 cos_enable;
u8 soft_reset;
};
/**
* struct idio_24_gpio - GPIO device private data structure
* @chip: instance of the gpio_chip
* @lock: synchronization lock to prevent I/O race conditions
* @reg: I/O address offset for the GPIO device registers
* @irq_mask: I/O bits affected by interrupts
*/
struct idio_24_gpio {
struct gpio_chip chip;
raw_spinlock_t lock;
__u8 __iomem *plx;
struct idio_24_gpio_reg __iomem *reg;
unsigned long irq_mask;
};
static int idio_24_gpio_get_direction(struct gpio_chip *chip,
unsigned int offset)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
const unsigned long out_mode_mask = BIT(1);
/* FET Outputs */
if (offset < 24)
return GPIO_LINE_DIRECTION_OUT;
/* Isolated Inputs */
if (offset < 48)
return GPIO_LINE_DIRECTION_IN;
/* TTL/CMOS I/O */
/* OUT MODE = 1 when TTL/CMOS Output Mode is set */
if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
static int idio_24_gpio_direction_input(struct gpio_chip *chip,
unsigned int offset)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
unsigned long flags;
unsigned int ctl_state;
const unsigned long out_mode_mask = BIT(1);
/* TTL/CMOS I/O */
if (offset > 47) {
raw_spin_lock_irqsave(&idio24gpio->lock, flags);
/* Clear TTL/CMOS Output Mode */
ctl_state = ioread8(&idio24gpio->reg->ctl) & ~out_mode_mask;
iowrite8(ctl_state, &idio24gpio->reg->ctl);
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
return 0;
}
static int idio_24_gpio_direction_output(struct gpio_chip *chip,
unsigned int offset, int value)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
unsigned long flags;
unsigned int ctl_state;
const unsigned long out_mode_mask = BIT(1);
/* TTL/CMOS I/O */
if (offset > 47) {
raw_spin_lock_irqsave(&idio24gpio->lock, flags);
/* Set TTL/CMOS Output Mode */
ctl_state = ioread8(&idio24gpio->reg->ctl) | out_mode_mask;
iowrite8(ctl_state, &idio24gpio->reg->ctl);
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
chip->set(chip, offset, value);
return 0;
}
static int idio_24_gpio_get(struct gpio_chip *chip, unsigned int offset)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
const unsigned long offset_mask = BIT(offset % 8);
const unsigned long out_mode_mask = BIT(1);
/* FET Outputs */
if (offset < 8)
return !!(ioread8(&idio24gpio->reg->out0_7) & offset_mask);
if (offset < 16)
return !!(ioread8(&idio24gpio->reg->out8_15) & offset_mask);
if (offset < 24)
return !!(ioread8(&idio24gpio->reg->out16_23) & offset_mask);
/* Isolated Inputs */
if (offset < 32)
return !!(ioread8(&idio24gpio->reg->in0_7) & offset_mask);
if (offset < 40)
return !!(ioread8(&idio24gpio->reg->in8_15) & offset_mask);
if (offset < 48)
return !!(ioread8(&idio24gpio->reg->in16_23) & offset_mask);
/* TTL/CMOS Outputs */
if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
return !!(ioread8(&idio24gpio->reg->ttl_out0_7) & offset_mask);
/* TTL/CMOS Inputs */
return !!(ioread8(&idio24gpio->reg->ttl_in0_7) & offset_mask);
}
static int idio_24_gpio_get_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
unsigned long offset;
unsigned long gpio_mask;
void __iomem *ports[] = {
&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
&idio24gpio->reg->out16_23, &idio24gpio->reg->in0_7,
&idio24gpio->reg->in8_15, &idio24gpio->reg->in16_23,
};
size_t index;
unsigned long port_state;
const unsigned long out_mode_mask = BIT(1);
/* clear bits array to a clean slate */
bitmap_zero(bits, chip->ngpio);
for_each_set_clump8(offset, gpio_mask, mask, ARRAY_SIZE(ports) * 8) {
index = offset / 8;
/* read bits from current gpio port (port 6 is TTL GPIO) */
if (index < 6)
port_state = ioread8(ports[index]);
else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask)
port_state = ioread8(&idio24gpio->reg->ttl_out0_7);
else
port_state = ioread8(&idio24gpio->reg->ttl_in0_7);
port_state &= gpio_mask;
bitmap_set_value8(bits, port_state, offset);
}
return 0;
}
static void idio_24_gpio_set(struct gpio_chip *chip, unsigned int offset,
int value)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
const unsigned long out_mode_mask = BIT(1);
void __iomem *base;
const unsigned int mask = BIT(offset % 8);
unsigned long flags;
unsigned int out_state;
/* Isolated Inputs */
if (offset > 23 && offset < 48)
return;
/* TTL/CMOS Inputs */
if (offset > 47 && !(ioread8(&idio24gpio->reg->ctl) & out_mode_mask))
return;
/* TTL/CMOS Outputs */
if (offset > 47)
base = &idio24gpio->reg->ttl_out0_7;
/* FET Outputs */
else if (offset > 15)
base = &idio24gpio->reg->out16_23;
else if (offset > 7)
base = &idio24gpio->reg->out8_15;
else
base = &idio24gpio->reg->out0_7;
raw_spin_lock_irqsave(&idio24gpio->lock, flags);
if (value)
out_state = ioread8(base) | mask;
else
out_state = ioread8(base) & ~mask;
iowrite8(out_state, base);
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
static void idio_24_gpio_set_multiple(struct gpio_chip *chip,
unsigned long *mask, unsigned long *bits)
{
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
unsigned long offset;
unsigned long gpio_mask;
void __iomem *ports[] = {
&idio24gpio->reg->out0_7, &idio24gpio->reg->out8_15,
&idio24gpio->reg->out16_23
};
size_t index;
unsigned long bitmask;
unsigned long flags;
unsigned long out_state;
const unsigned long out_mode_mask = BIT(1);
for_each_set_clump8(offset, gpio_mask, mask, ARRAY_SIZE(ports) * 8) {
index = offset / 8;
bitmask = bitmap_get_value8(bits, offset) & gpio_mask;
raw_spin_lock_irqsave(&idio24gpio->lock, flags);
/* read bits from current gpio port (port 6 is TTL GPIO) */
if (index < 6) {
out_state = ioread8(ports[index]);
} else if (ioread8(&idio24gpio->reg->ctl) & out_mode_mask) {
out_state = ioread8(&idio24gpio->reg->ttl_out0_7);
} else {
/* skip TTL GPIO if set for input */
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
continue;
}
/* set requested bit states */
out_state &= ~gpio_mask;
out_state |= bitmask;
/* write bits for current gpio port (port 6 is TTL GPIO) */
if (index < 6)
iowrite8(out_state, ports[index]);
else
iowrite8(out_state, &idio24gpio->reg->ttl_out0_7);
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
}
static void idio_24_irq_ack(struct irq_data *data)
{
}
static void idio_24_irq_mask(struct irq_data *data)
{
struct gpio_chip *const chip = irq_data_get_irq_chip_data(data);
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
unsigned long flags;
const unsigned long bit_offset = irqd_to_hwirq(data) - 24;
unsigned char new_irq_mask;
const unsigned long bank_offset = bit_offset / 8;
unsigned char cos_enable_state;
raw_spin_lock_irqsave(&idio24gpio->lock, flags);
idio24gpio->irq_mask &= ~BIT(bit_offset);
new_irq_mask = idio24gpio->irq_mask >> bank_offset * 8;
if (!new_irq_mask) {
cos_enable_state = ioread8(&idio24gpio->reg->cos_enable);
/* Disable Rising Edge detection */
cos_enable_state &= ~BIT(bank_offset);
/* Disable Falling Edge detection */
cos_enable_state &= ~BIT(bank_offset + 4);
iowrite8(cos_enable_state, &idio24gpio->reg->cos_enable);
}
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
static void idio_24_irq_unmask(struct irq_data *data)
{
struct gpio_chip *const chip = irq_data_get_irq_chip_data(data);
struct idio_24_gpio *const idio24gpio = gpiochip_get_data(chip);
unsigned long flags;
unsigned char prev_irq_mask;
const unsigned long bit_offset = irqd_to_hwirq(data) - 24;
const unsigned long bank_offset = bit_offset / 8;
unsigned char cos_enable_state;
raw_spin_lock_irqsave(&idio24gpio->lock, flags);
prev_irq_mask = idio24gpio->irq_mask >> bank_offset * 8;
idio24gpio->irq_mask |= BIT(bit_offset);
if (!prev_irq_mask) {
cos_enable_state = ioread8(&idio24gpio->reg->cos_enable);
/* Enable Rising Edge detection */
cos_enable_state |= BIT(bank_offset);
/* Enable Falling Edge detection */
cos_enable_state |= BIT(bank_offset + 4);
iowrite8(cos_enable_state, &idio24gpio->reg->cos_enable);
}
raw_spin_unlock_irqrestore(&idio24gpio->lock, flags);
}
static int idio_24_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 struct irq_chip idio_24_irqchip = {
.name = "pcie-idio-24",
.irq_ack = idio_24_irq_ack,
.irq_mask = idio_24_irq_mask,
.irq_unmask = idio_24_irq_unmask,
.irq_set_type = idio_24_irq_set_type
};
static irqreturn_t idio_24_irq_handler(int irq, void *dev_id)
{
struct idio_24_gpio *const idio24gpio = dev_id;
unsigned long irq_status;
struct gpio_chip *const chip = &idio24gpio->chip;
unsigned long irq_mask;
int gpio;
raw_spin_lock(&idio24gpio->lock);
/* Read Change-Of-State status */
irq_status = ioread32(&idio24gpio->reg->cos0_7);
raw_spin_unlock(&idio24gpio->lock);
/* Make sure our device generated IRQ */
if (!irq_status)
return IRQ_NONE;
/* Handle only unmasked IRQ */
irq_mask = idio24gpio->irq_mask & irq_status;
for_each_set_bit(gpio, &irq_mask, chip->ngpio - 24)
generic_handle_irq(irq_find_mapping(chip->irq.domain,
gpio + 24));
raw_spin_lock(&idio24gpio->lock);
/* Clear Change-Of-State status */
iowrite32(irq_status, &idio24gpio->reg->cos0_7);
raw_spin_unlock(&idio24gpio->lock);
return IRQ_HANDLED;
}
#define IDIO_24_NGPIO 56
static const char *idio_24_names[IDIO_24_NGPIO] = {
"OUT0", "OUT1", "OUT2", "OUT3", "OUT4", "OUT5", "OUT6", "OUT7",
"OUT8", "OUT9", "OUT10", "OUT11", "OUT12", "OUT13", "OUT14", "OUT15",
"OUT16", "OUT17", "OUT18", "OUT19", "OUT20", "OUT21", "OUT22", "OUT23",
"IIN0", "IIN1", "IIN2", "IIN3", "IIN4", "IIN5", "IIN6", "IIN7",
"IIN8", "IIN9", "IIN10", "IIN11", "IIN12", "IIN13", "IIN14", "IIN15",
"IIN16", "IIN17", "IIN18", "IIN19", "IIN20", "IIN21", "IIN22", "IIN23",
"TTL0", "TTL1", "TTL2", "TTL3", "TTL4", "TTL5", "TTL6", "TTL7"
};
static int idio_24_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
struct device *const dev = &pdev->dev;
struct idio_24_gpio *idio24gpio;
int err;
const size_t pci_plx_bar_index = 1;
const size_t pci_bar_index = 2;
const char *const name = pci_name(pdev);
struct gpio_irq_chip *girq;
idio24gpio = devm_kzalloc(dev, sizeof(*idio24gpio), GFP_KERNEL);
if (!idio24gpio)
return -ENOMEM;
err = pcim_enable_device(pdev);
if (err) {
dev_err(dev, "Failed to enable PCI device (%d)\n", err);
return err;
}
err = pcim_iomap_regions(pdev, BIT(pci_plx_bar_index) | BIT(pci_bar_index), name);
if (err) {
dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err);
return err;
}
idio24gpio->plx = pcim_iomap_table(pdev)[pci_plx_bar_index];
idio24gpio->reg = pcim_iomap_table(pdev)[pci_bar_index];
idio24gpio->chip.label = name;
idio24gpio->chip.parent = dev;
idio24gpio->chip.owner = THIS_MODULE;
idio24gpio->chip.base = -1;
idio24gpio->chip.ngpio = IDIO_24_NGPIO;
idio24gpio->chip.names = idio_24_names;
idio24gpio->chip.get_direction = idio_24_gpio_get_direction;
idio24gpio->chip.direction_input = idio_24_gpio_direction_input;
idio24gpio->chip.direction_output = idio_24_gpio_direction_output;
idio24gpio->chip.get = idio_24_gpio_get;
idio24gpio->chip.get_multiple = idio_24_gpio_get_multiple;
idio24gpio->chip.set = idio_24_gpio_set;
idio24gpio->chip.set_multiple = idio_24_gpio_set_multiple;
girq = &idio24gpio->chip.irq;
girq->chip = &idio_24_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;
raw_spin_lock_init(&idio24gpio->lock);
/* Software board reset */
iowrite8(0, &idio24gpio->reg->soft_reset);
/*
* enable PLX PEX8311 internal PCI wire interrupt and local interrupt
* input
*/
iowrite8((INTCSR_INTERNAL_PCI_WIRE | INTCSR_LOCAL_INPUT) >> 8,
idio24gpio->plx + PLX_PEX8311_PCI_LCS_INTCSR + 1);
err = devm_gpiochip_add_data(dev, &idio24gpio->chip, idio24gpio);
if (err) {
dev_err(dev, "GPIO registering failed (%d)\n", err);
return err;
}
err = devm_request_irq(dev, pdev->irq, idio_24_irq_handler, IRQF_SHARED,
name, idio24gpio);
if (err) {
dev_err(dev, "IRQ handler registering failed (%d)\n", err);
return err;
}
return 0;
}
static const struct pci_device_id idio_24_pci_dev_id[] = {
{ PCI_DEVICE(0x494F, 0x0FD0) }, { PCI_DEVICE(0x494F, 0x0BD0) },
{ PCI_DEVICE(0x494F, 0x07D0) }, { PCI_DEVICE(0x494F, 0x0FC0) },
{ 0 }
};
MODULE_DEVICE_TABLE(pci, idio_24_pci_dev_id);
static struct pci_driver idio_24_driver = {
.name = "pcie-idio-24",
.id_table = idio_24_pci_dev_id,
.probe = idio_24_probe
};
module_pci_driver(idio_24_driver);
MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
MODULE_DESCRIPTION("ACCES PCIe-IDIO-24 GPIO driver");
MODULE_LICENSE("GPL v2");