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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpio/gpio-sch.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | drivers/gpio/gpio-sch.c | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-sch.c b/drivers/gpio/gpio-sch.c new file mode 100644 index 000000000..8a83f7bf4 --- /dev/null +++ b/drivers/gpio/gpio-sch.c @@ -0,0 +1,416 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * GPIO interface for Intel Poulsbo SCH + * + * Copyright (c) 2010 CompuLab Ltd + * Author: Denis Turischev <denis@compulab.co.il> + */ + +#include <linux/acpi.h> +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/gpio/driver.h> +#include <linux/io.h> +#include <linux/irq.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/pci_ids.h> +#include <linux/platform_device.h> +#include <linux/types.h> + +#define GEN 0x00 +#define GIO 0x04 +#define GLV 0x08 +#define GTPE 0x0c +#define GTNE 0x10 +#define GGPE 0x14 +#define GSMI 0x18 +#define GTS 0x1c + +#define CORE_BANK_OFFSET 0x00 +#define RESUME_BANK_OFFSET 0x20 + +/* + * iLB datasheet describes GPE0BLK registers, in particular GPE0E.GPIO bit. + * Document Number: 328195-001 + */ +#define GPE0E_GPIO 14 + +struct sch_gpio { + struct gpio_chip chip; + spinlock_t lock; + unsigned short iobase; + unsigned short resume_base; + + /* GPE handling */ + u32 gpe; + acpi_gpe_handler gpe_handler; +}; + +static unsigned int sch_gpio_offset(struct sch_gpio *sch, unsigned int gpio, + unsigned int reg) +{ + unsigned int base = CORE_BANK_OFFSET; + + if (gpio >= sch->resume_base) { + gpio -= sch->resume_base; + base = RESUME_BANK_OFFSET; + } + + return base + reg + gpio / 8; +} + +static unsigned int sch_gpio_bit(struct sch_gpio *sch, unsigned int gpio) +{ + if (gpio >= sch->resume_base) + gpio -= sch->resume_base; + return gpio % 8; +} + +static int sch_gpio_reg_get(struct sch_gpio *sch, unsigned int gpio, unsigned int reg) +{ + unsigned short offset, bit; + u8 reg_val; + + offset = sch_gpio_offset(sch, gpio, reg); + bit = sch_gpio_bit(sch, gpio); + + reg_val = !!(inb(sch->iobase + offset) & BIT(bit)); + + return reg_val; +} + +static void sch_gpio_reg_set(struct sch_gpio *sch, unsigned int gpio, unsigned int reg, + int val) +{ + unsigned short offset, bit; + u8 reg_val; + + offset = sch_gpio_offset(sch, gpio, reg); + bit = sch_gpio_bit(sch, gpio); + + reg_val = inb(sch->iobase + offset); + + if (val) + outb(reg_val | BIT(bit), sch->iobase + offset); + else + outb((reg_val & ~BIT(bit)), sch->iobase + offset); +} + +static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned int gpio_num) +{ + struct sch_gpio *sch = gpiochip_get_data(gc); + unsigned long flags; + + spin_lock_irqsave(&sch->lock, flags); + sch_gpio_reg_set(sch, gpio_num, GIO, 1); + spin_unlock_irqrestore(&sch->lock, flags); + return 0; +} + +static int sch_gpio_get(struct gpio_chip *gc, unsigned int gpio_num) +{ + struct sch_gpio *sch = gpiochip_get_data(gc); + + return sch_gpio_reg_get(sch, gpio_num, GLV); +} + +static void sch_gpio_set(struct gpio_chip *gc, unsigned int gpio_num, int val) +{ + struct sch_gpio *sch = gpiochip_get_data(gc); + unsigned long flags; + + spin_lock_irqsave(&sch->lock, flags); + sch_gpio_reg_set(sch, gpio_num, GLV, val); + spin_unlock_irqrestore(&sch->lock, flags); +} + +static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned int gpio_num, + int val) +{ + struct sch_gpio *sch = gpiochip_get_data(gc); + unsigned long flags; + + spin_lock_irqsave(&sch->lock, flags); + sch_gpio_reg_set(sch, gpio_num, GIO, 0); + spin_unlock_irqrestore(&sch->lock, flags); + + /* + * according to the datasheet, writing to the level register has no + * effect when GPIO is programmed as input. + * Actually the level register is read-only when configured as input. + * Thus presetting the output level before switching to output is _NOT_ possible. + * Hence we set the level after configuring the GPIO as output. + * But we cannot prevent a short low pulse if direction is set to high + * and an external pull-up is connected. + */ + sch_gpio_set(gc, gpio_num, val); + return 0; +} + +static int sch_gpio_get_direction(struct gpio_chip *gc, unsigned int gpio_num) +{ + struct sch_gpio *sch = gpiochip_get_data(gc); + + if (sch_gpio_reg_get(sch, gpio_num, GIO)) + return GPIO_LINE_DIRECTION_IN; + + return GPIO_LINE_DIRECTION_OUT; +} + +static const struct gpio_chip sch_gpio_chip = { + .label = "sch_gpio", + .owner = THIS_MODULE, + .direction_input = sch_gpio_direction_in, + .get = sch_gpio_get, + .direction_output = sch_gpio_direction_out, + .set = sch_gpio_set, + .get_direction = sch_gpio_get_direction, +}; + +static int sch_irq_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct sch_gpio *sch = gpiochip_get_data(gc); + irq_hw_number_t gpio_num = irqd_to_hwirq(d); + unsigned long flags; + int rising, falling; + + switch (type & IRQ_TYPE_SENSE_MASK) { + case IRQ_TYPE_EDGE_RISING: + rising = 1; + falling = 0; + break; + case IRQ_TYPE_EDGE_FALLING: + rising = 0; + falling = 1; + break; + case IRQ_TYPE_EDGE_BOTH: + rising = 1; + falling = 1; + break; + default: + return -EINVAL; + } + + spin_lock_irqsave(&sch->lock, flags); + + sch_gpio_reg_set(sch, gpio_num, GTPE, rising); + sch_gpio_reg_set(sch, gpio_num, GTNE, falling); + + irq_set_handler_locked(d, handle_edge_irq); + + spin_unlock_irqrestore(&sch->lock, flags); + + return 0; +} + +static void sch_irq_ack(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct sch_gpio *sch = gpiochip_get_data(gc); + irq_hw_number_t gpio_num = irqd_to_hwirq(d); + unsigned long flags; + + spin_lock_irqsave(&sch->lock, flags); + sch_gpio_reg_set(sch, gpio_num, GTS, 1); + spin_unlock_irqrestore(&sch->lock, flags); +} + +static void sch_irq_mask_unmask(struct gpio_chip *gc, irq_hw_number_t gpio_num, int val) +{ + struct sch_gpio *sch = gpiochip_get_data(gc); + unsigned long flags; + + spin_lock_irqsave(&sch->lock, flags); + sch_gpio_reg_set(sch, gpio_num, GGPE, val); + spin_unlock_irqrestore(&sch->lock, flags); +} + +static void sch_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + irq_hw_number_t gpio_num = irqd_to_hwirq(d); + + sch_irq_mask_unmask(gc, gpio_num, 0); + gpiochip_disable_irq(gc, gpio_num); +} + +static void sch_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + irq_hw_number_t gpio_num = irqd_to_hwirq(d); + + gpiochip_enable_irq(gc, gpio_num); + sch_irq_mask_unmask(gc, gpio_num, 1); +} + +static const struct irq_chip sch_irqchip = { + .name = "sch_gpio", + .irq_ack = sch_irq_ack, + .irq_mask = sch_irq_mask, + .irq_unmask = sch_irq_unmask, + .irq_set_type = sch_irq_type, + .flags = IRQCHIP_IMMUTABLE, + GPIOCHIP_IRQ_RESOURCE_HELPERS, +}; + +static u32 sch_gpio_gpe_handler(acpi_handle gpe_device, u32 gpe, void *context) +{ + struct sch_gpio *sch = context; + struct gpio_chip *gc = &sch->chip; + unsigned long core_status, resume_status; + unsigned long pending; + unsigned long flags; + int offset; + u32 ret; + + spin_lock_irqsave(&sch->lock, flags); + + core_status = inl(sch->iobase + CORE_BANK_OFFSET + GTS); + resume_status = inl(sch->iobase + RESUME_BANK_OFFSET + GTS); + + spin_unlock_irqrestore(&sch->lock, flags); + + pending = (resume_status << sch->resume_base) | core_status; + for_each_set_bit(offset, &pending, sch->chip.ngpio) + generic_handle_domain_irq(gc->irq.domain, offset); + + /* Set returning value depending on whether we handled an interrupt */ + ret = pending ? ACPI_INTERRUPT_HANDLED : ACPI_INTERRUPT_NOT_HANDLED; + + /* Acknowledge GPE to ACPICA */ + ret |= ACPI_REENABLE_GPE; + + return ret; +} + +static void sch_gpio_remove_gpe_handler(void *data) +{ + struct sch_gpio *sch = data; + + acpi_disable_gpe(NULL, sch->gpe); + acpi_remove_gpe_handler(NULL, sch->gpe, sch->gpe_handler); +} + +static int sch_gpio_install_gpe_handler(struct sch_gpio *sch) +{ + struct device *dev = sch->chip.parent; + acpi_status status; + + status = acpi_install_gpe_handler(NULL, sch->gpe, ACPI_GPE_LEVEL_TRIGGERED, + sch->gpe_handler, sch); + if (ACPI_FAILURE(status)) { + dev_err(dev, "Failed to install GPE handler for %u: %s\n", + sch->gpe, acpi_format_exception(status)); + return -ENODEV; + } + + status = acpi_enable_gpe(NULL, sch->gpe); + if (ACPI_FAILURE(status)) { + dev_err(dev, "Failed to enable GPE handler for %u: %s\n", + sch->gpe, acpi_format_exception(status)); + acpi_remove_gpe_handler(NULL, sch->gpe, sch->gpe_handler); + return -ENODEV; + } + + return devm_add_action_or_reset(dev, sch_gpio_remove_gpe_handler, sch); +} + +static int sch_gpio_probe(struct platform_device *pdev) +{ + struct gpio_irq_chip *girq; + struct sch_gpio *sch; + struct resource *res; + int ret; + + sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL); + if (!sch) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_IO, 0); + if (!res) + return -EBUSY; + + if (!devm_request_region(&pdev->dev, res->start, resource_size(res), + pdev->name)) + return -EBUSY; + + spin_lock_init(&sch->lock); + sch->iobase = res->start; + sch->chip = sch_gpio_chip; + sch->chip.label = dev_name(&pdev->dev); + sch->chip.parent = &pdev->dev; + + switch (pdev->id) { + case PCI_DEVICE_ID_INTEL_SCH_LPC: + sch->resume_base = 10; + sch->chip.ngpio = 14; + + /* + * GPIO[6:0] enabled by default + * GPIO7 is configured by the CMC as SLPIOVR + * Enable GPIO[9:8] core powered gpios explicitly + */ + sch_gpio_reg_set(sch, 8, GEN, 1); + sch_gpio_reg_set(sch, 9, GEN, 1); + /* + * SUS_GPIO[2:0] enabled by default + * Enable SUS_GPIO3 resume powered gpio explicitly + */ + sch_gpio_reg_set(sch, 13, GEN, 1); + break; + + case PCI_DEVICE_ID_INTEL_ITC_LPC: + sch->resume_base = 5; + sch->chip.ngpio = 14; + break; + + case PCI_DEVICE_ID_INTEL_CENTERTON_ILB: + sch->resume_base = 21; + sch->chip.ngpio = 30; + break; + + case PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB: + sch->resume_base = 2; + sch->chip.ngpio = 8; + break; + + default: + return -ENODEV; + } + + platform_set_drvdata(pdev, sch); + + girq = &sch->chip.irq; + gpio_irq_chip_set_chip(girq, &sch_irqchip); + girq->num_parents = 0; + girq->parents = NULL; + girq->parent_handler = NULL; + girq->default_type = IRQ_TYPE_NONE; + girq->handler = handle_bad_irq; + + /* GPE setup is optional */ + sch->gpe = GPE0E_GPIO; + sch->gpe_handler = sch_gpio_gpe_handler; + + ret = sch_gpio_install_gpe_handler(sch); + if (ret) + dev_warn(&pdev->dev, "Can't setup GPE, no IRQ support\n"); + + return devm_gpiochip_add_data(&pdev->dev, &sch->chip, sch); +} + +static struct platform_driver sch_gpio_driver = { + .driver = { + .name = "sch_gpio", + }, + .probe = sch_gpio_probe, +}; + +module_platform_driver(sch_gpio_driver); + +MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>"); +MODULE_DESCRIPTION("GPIO interface for Intel Poulsbo SCH"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:sch_gpio"); |