diff options
Diffstat (limited to 'drivers/platform/x86/intel_int0002_vgpio.c')
| -rw-r--r-- | drivers/platform/x86/intel_int0002_vgpio.c | 228 |
1 files changed, 0 insertions, 228 deletions
diff --git a/drivers/platform/x86/intel_int0002_vgpio.c b/drivers/platform/x86/intel_int0002_vgpio.c deleted file mode 100644 index 4b8f7305fc8a..000000000000 --- a/drivers/platform/x86/intel_int0002_vgpio.c +++ /dev/null @@ -1,228 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Intel INT0002 "Virtual GPIO" driver - * - * Copyright (C) 2017 Hans de Goede <hdegoede@redhat.com> - * - * Loosely based on android x86 kernel code which is: - * - * Copyright (c) 2014, Intel Corporation. - * - * Author: Dyut Kumar Sil <dyut.k.sil@intel.com> - * - * Some peripherals on Bay Trail and Cherry Trail platforms signal a Power - * Management Event (PME) to the Power Management Controller (PMC) to wakeup - * the system. When this happens software needs to clear the PME bus 0 status - * bit in the GPE0a_STS register to avoid an IRQ storm on IRQ 9. - * - * This is modelled in ACPI through the INT0002 ACPI device, which is - * called a "Virtual GPIO controller" in ACPI because it defines the event - * handler to call when the PME triggers through _AEI and _L02 / _E02 - * methods as would be done for a real GPIO interrupt in ACPI. Note this - * is a hack to define an AML event handler for the PME while using existing - * ACPI mechanisms, this is not a real GPIO at all. - * - * This driver will bind to the INT0002 device, and register as a GPIO - * controller, letting gpiolib-acpi.c call the _L02 handler as it would - * for a real GPIO controller. - */ - -#include <linux/acpi.h> -#include <linux/bitmap.h> -#include <linux/gpio/driver.h> -#include <linux/interrupt.h> -#include <linux/io.h> -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/platform_device.h> -#include <linux/slab.h> -#include <linux/suspend.h> - -#include <asm/cpu_device_id.h> -#include <asm/intel-family.h> - -#define DRV_NAME "INT0002 Virtual GPIO" - -/* For some reason the virtual GPIO pin tied to the GPE is numbered pin 2 */ -#define GPE0A_PME_B0_VIRT_GPIO_PIN 2 - -#define GPE0A_PME_B0_STS_BIT BIT(13) -#define GPE0A_PME_B0_EN_BIT BIT(13) -#define GPE0A_STS_PORT 0x420 -#define GPE0A_EN_PORT 0x428 - -#define ICPU(model) { X86_VENDOR_INTEL, 6, model, X86_FEATURE_ANY, } - -static const struct x86_cpu_id int0002_cpu_ids[] = { - ICPU(INTEL_FAM6_ATOM_SILVERMONT), /* Valleyview, Bay Trail */ - ICPU(INTEL_FAM6_ATOM_AIRMONT), /* Braswell, Cherry Trail */ - {} -}; - -/* - * As this is not a real GPIO at all, but just a hack to model an event in - * ACPI the get / set functions are dummy functions. - */ - -static int int0002_gpio_get(struct gpio_chip *chip, unsigned int offset) -{ - return 0; -} - -static void int0002_gpio_set(struct gpio_chip *chip, unsigned int offset, - int value) -{ -} - -static int int0002_gpio_direction_output(struct gpio_chip *chip, - unsigned int offset, int value) -{ - return 0; -} - -static void int0002_irq_ack(struct irq_data *data) -{ - outl(GPE0A_PME_B0_STS_BIT, GPE0A_STS_PORT); -} - -static void int0002_irq_unmask(struct irq_data *data) -{ - u32 gpe_en_reg; - - gpe_en_reg = inl(GPE0A_EN_PORT); - gpe_en_reg |= GPE0A_PME_B0_EN_BIT; - outl(gpe_en_reg, GPE0A_EN_PORT); -} - -static void int0002_irq_mask(struct irq_data *data) -{ - u32 gpe_en_reg; - - gpe_en_reg = inl(GPE0A_EN_PORT); - gpe_en_reg &= ~GPE0A_PME_B0_EN_BIT; - outl(gpe_en_reg, GPE0A_EN_PORT); -} - -static int int0002_irq_set_wake(struct irq_data *data, unsigned int on) -{ - struct gpio_chip *chip = irq_data_get_irq_chip_data(data); - struct platform_device *pdev = to_platform_device(chip->parent); - int irq = platform_get_irq(pdev, 0); - - /* Propagate to parent irq */ - if (on) - enable_irq_wake(irq); - else - disable_irq_wake(irq); - - return 0; -} - -static irqreturn_t int0002_irq(int irq, void *data) -{ - struct gpio_chip *chip = data; - u32 gpe_sts_reg; - - gpe_sts_reg = inl(GPE0A_STS_PORT); - if (!(gpe_sts_reg & GPE0A_PME_B0_STS_BIT)) - return IRQ_NONE; - - generic_handle_irq(irq_find_mapping(chip->irq.domain, - GPE0A_PME_B0_VIRT_GPIO_PIN)); - - pm_system_wakeup(); - - return IRQ_HANDLED; -} - -static struct irq_chip int0002_irqchip = { - .name = DRV_NAME, - .irq_ack = int0002_irq_ack, - .irq_mask = int0002_irq_mask, - .irq_unmask = int0002_irq_unmask, - .irq_set_wake = int0002_irq_set_wake, -}; - -static int int0002_probe(struct platform_device *pdev) -{ - struct device *dev = &pdev->dev; - const struct x86_cpu_id *cpu_id; - struct gpio_chip *chip; - int irq, ret; - - /* Menlow has a different INT0002 device? <sigh> */ - cpu_id = x86_match_cpu(int0002_cpu_ids); - if (!cpu_id) - return -ENODEV; - - irq = platform_get_irq(pdev, 0); - if (irq < 0) { - dev_err(dev, "Error getting IRQ: %d\n", irq); - return irq; - } - - chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL); - if (!chip) - return -ENOMEM; - - chip->label = DRV_NAME; - chip->parent = dev; - chip->owner = THIS_MODULE; - chip->get = int0002_gpio_get; - chip->set = int0002_gpio_set; - chip->direction_input = int0002_gpio_get; - chip->direction_output = int0002_gpio_direction_output; - chip->base = -1; - chip->ngpio = GPE0A_PME_B0_VIRT_GPIO_PIN + 1; - chip->irq.need_valid_mask = true; - - ret = devm_gpiochip_add_data(&pdev->dev, chip, NULL); - if (ret) { - dev_err(dev, "Error adding gpio chip: %d\n", ret); - return ret; - } - - bitmap_clear(chip->irq.valid_mask, 0, GPE0A_PME_B0_VIRT_GPIO_PIN); - - /* - * We manually request the irq here instead of passing a flow-handler - * to gpiochip_set_chained_irqchip, because the irq is shared. - */ - ret = devm_request_irq(dev, irq, int0002_irq, - IRQF_SHARED, "INT0002", chip); - if (ret) { - dev_err(dev, "Error requesting IRQ %d: %d\n", irq, ret); - return ret; - } - - ret = gpiochip_irqchip_add(chip, &int0002_irqchip, 0, handle_edge_irq, - IRQ_TYPE_NONE); - if (ret) { - dev_err(dev, "Error adding irqchip: %d\n", ret); - return ret; - } - - gpiochip_set_chained_irqchip(chip, &int0002_irqchip, irq, NULL); - - return 0; -} - -static const struct acpi_device_id int0002_acpi_ids[] = { - { "INT0002", 0 }, - { }, -}; -MODULE_DEVICE_TABLE(acpi, int0002_acpi_ids); - -static struct platform_driver int0002_driver = { - .driver = { - .name = DRV_NAME, - .acpi_match_table = int0002_acpi_ids, - }, - .probe = int0002_probe, -}; - -module_platform_driver(int0002_driver); - -MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); -MODULE_DESCRIPTION("Intel INT0002 Virtual GPIO driver"); -MODULE_LICENSE("GPL v2"); |