diff options
Diffstat (limited to 'drivers/gpio/gpio-pcie-idio-24.c')
| -rw-r--r-- | drivers/gpio/gpio-pcie-idio-24.c | 447 |
1 files changed, 447 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-pcie-idio-24.c b/drivers/gpio/gpio-pcie-idio-24.c new file mode 100644 index 000000000000..f666e2e69074 --- /dev/null +++ b/drivers/gpio/gpio-pcie-idio-24.c @@ -0,0 +1,447 @@ +// 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/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> + +/** + * 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; + 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 0; + + /* Isolated Inputs */ + if (offset < 48) + return 1; + + /* TTL/CMOS I/O */ + /* OUT MODE = 1 when TTL/CMOS Output Mode is set */ + return !(ioread8(&idio24gpio->reg->ctl) & out_mode_mask); +} + +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 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_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 * 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; + + 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 * 8; + unsigned char cos_enable_state; + + raw_spin_lock_irqsave(&idio24gpio->lock, flags); + + prev_irq_mask = idio24gpio->irq_mask >> bank_offset; + 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_bar_index = 2; + const char *const name = pci_name(pdev); + + 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_bar_index), name); + if (err) { + dev_err(dev, "Unable to map PCI I/O addresses (%d)\n", err); + return err; + } + + 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.set = idio_24_gpio_set; + + raw_spin_lock_init(&idio24gpio->lock); + + /* Software board reset */ + iowrite8(0, &idio24gpio->reg->soft_reset); + + err = devm_gpiochip_add_data(dev, &idio24gpio->chip, idio24gpio); + if (err) { + dev_err(dev, "GPIO registering failed (%d)\n", err); + return err; + } + + err = gpiochip_irqchip_add(&idio24gpio->chip, &idio_24_irqchip, 0, + handle_edge_irq, IRQ_TYPE_NONE); + if (err) { + dev_err(dev, "Could not add irqchip (%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"); |