YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 1 | /* |
| 2 | * AMD Promontory GPIO driver |
| 3 | * |
| 4 | * Copyright (C) 2015 ASMedia Technology Inc. |
| 5 | * Author: YD Tseng <yd_tseng@asmedia.com.tw> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/kernel.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/gpio/driver.h> |
| 15 | #include <linux/spinlock.h> |
| 16 | #include <linux/acpi.h> |
| 17 | #include <linux/platform_device.h> |
| 18 | |
| 19 | #define PT_TOTAL_GPIO 8 |
| 20 | |
| 21 | /* PCI-E MMIO register offsets */ |
| 22 | #define PT_DIRECTION_REG 0x00 |
| 23 | #define PT_INPUTDATA_REG 0x04 |
| 24 | #define PT_OUTPUTDATA_REG 0x08 |
| 25 | #define PT_CLOCKRATE_REG 0x0C |
| 26 | #define PT_SYNC_REG 0x28 |
| 27 | |
| 28 | struct pt_gpio_chip { |
| 29 | struct gpio_chip gc; |
| 30 | void __iomem *reg_base; |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 31 | }; |
| 32 | |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 33 | static int pt_gpio_request(struct gpio_chip *gc, unsigned offset) |
| 34 | { |
Linus Walleij | fb72288 | 2015-12-04 15:29:41 +0100 | [diff] [blame] | 35 | struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 36 | unsigned long flags; |
| 37 | u32 using_pins; |
| 38 | |
Linus Walleij | 58383c78 | 2015-11-04 09:56:26 +0100 | [diff] [blame] | 39 | dev_dbg(gc->parent, "pt_gpio_request offset=%x\n", offset); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 40 | |
Axel Lin | 574b782 | 2016-02-29 22:00:01 +0800 | [diff] [blame] | 41 | spin_lock_irqsave(&gc->bgpio_lock, flags); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 42 | |
| 43 | using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG); |
| 44 | if (using_pins & BIT(offset)) { |
Linus Walleij | 58383c78 | 2015-11-04 09:56:26 +0100 | [diff] [blame] | 45 | dev_warn(gc->parent, "PT GPIO pin %x reconfigured\n", |
| 46 | offset); |
Axel Lin | 574b782 | 2016-02-29 22:00:01 +0800 | [diff] [blame] | 47 | spin_unlock_irqrestore(&gc->bgpio_lock, flags); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 48 | return -EINVAL; |
| 49 | } |
| 50 | |
| 51 | writel(using_pins | BIT(offset), pt_gpio->reg_base + PT_SYNC_REG); |
| 52 | |
Axel Lin | 574b782 | 2016-02-29 22:00:01 +0800 | [diff] [blame] | 53 | spin_unlock_irqrestore(&gc->bgpio_lock, flags); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 54 | |
| 55 | return 0; |
| 56 | } |
| 57 | |
| 58 | static void pt_gpio_free(struct gpio_chip *gc, unsigned offset) |
| 59 | { |
Linus Walleij | fb72288 | 2015-12-04 15:29:41 +0100 | [diff] [blame] | 60 | struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 61 | unsigned long flags; |
| 62 | u32 using_pins; |
| 63 | |
Axel Lin | 574b782 | 2016-02-29 22:00:01 +0800 | [diff] [blame] | 64 | spin_lock_irqsave(&gc->bgpio_lock, flags); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 65 | |
| 66 | using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG); |
| 67 | using_pins &= ~BIT(offset); |
| 68 | writel(using_pins, pt_gpio->reg_base + PT_SYNC_REG); |
| 69 | |
Axel Lin | 574b782 | 2016-02-29 22:00:01 +0800 | [diff] [blame] | 70 | spin_unlock_irqrestore(&gc->bgpio_lock, flags); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 71 | |
Linus Walleij | 58383c78 | 2015-11-04 09:56:26 +0100 | [diff] [blame] | 72 | dev_dbg(gc->parent, "pt_gpio_free offset=%x\n", offset); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 73 | } |
| 74 | |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 75 | static int pt_gpio_probe(struct platform_device *pdev) |
| 76 | { |
| 77 | struct device *dev = &pdev->dev; |
| 78 | struct acpi_device *acpi_dev; |
| 79 | acpi_handle handle = ACPI_HANDLE(dev); |
| 80 | struct pt_gpio_chip *pt_gpio; |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 81 | int ret = 0; |
| 82 | |
| 83 | if (acpi_bus_get_device(handle, &acpi_dev)) { |
| 84 | dev_err(dev, "PT GPIO device node not found\n"); |
| 85 | return -ENODEV; |
| 86 | } |
| 87 | |
| 88 | pt_gpio = devm_kzalloc(dev, sizeof(struct pt_gpio_chip), GFP_KERNEL); |
| 89 | if (!pt_gpio) |
| 90 | return -ENOMEM; |
| 91 | |
Enrico Weigelt, metux IT consult | bb17a27 | 2019-03-11 19:54:41 +0100 | [diff] [blame] | 92 | pt_gpio->reg_base = devm_platform_ioremap_resource(pdev, 0); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 93 | if (IS_ERR(pt_gpio->reg_base)) { |
| 94 | dev_err(&pdev->dev, "Failed to map MMIO resource for PT GPIO.\n"); |
| 95 | return PTR_ERR(pt_gpio->reg_base); |
| 96 | } |
| 97 | |
Axel Lin | 574b782 | 2016-02-29 22:00:01 +0800 | [diff] [blame] | 98 | ret = bgpio_init(&pt_gpio->gc, dev, 4, |
| 99 | pt_gpio->reg_base + PT_INPUTDATA_REG, |
| 100 | pt_gpio->reg_base + PT_OUTPUTDATA_REG, NULL, |
| 101 | pt_gpio->reg_base + PT_DIRECTION_REG, NULL, |
| 102 | BGPIOF_READ_OUTPUT_REG_SET); |
| 103 | if (ret) { |
| 104 | dev_err(&pdev->dev, "bgpio_init failed\n"); |
| 105 | return ret; |
| 106 | } |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 107 | |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 108 | pt_gpio->gc.owner = THIS_MODULE; |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 109 | pt_gpio->gc.request = pt_gpio_request; |
| 110 | pt_gpio->gc.free = pt_gpio_free; |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 111 | pt_gpio->gc.ngpio = PT_TOTAL_GPIO; |
| 112 | #if defined(CONFIG_OF_GPIO) |
| 113 | pt_gpio->gc.of_node = pdev->dev.of_node; |
| 114 | #endif |
Linus Walleij | fb72288 | 2015-12-04 15:29:41 +0100 | [diff] [blame] | 115 | ret = gpiochip_add_data(&pt_gpio->gc, pt_gpio); |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 116 | if (ret) { |
| 117 | dev_err(&pdev->dev, "Failed to register GPIO lib\n"); |
| 118 | return ret; |
| 119 | } |
| 120 | |
| 121 | platform_set_drvdata(pdev, pt_gpio); |
| 122 | |
| 123 | /* initialize register setting */ |
| 124 | writel(0, pt_gpio->reg_base + PT_SYNC_REG); |
| 125 | writel(0, pt_gpio->reg_base + PT_CLOCKRATE_REG); |
| 126 | |
| 127 | dev_dbg(&pdev->dev, "PT GPIO driver loaded\n"); |
| 128 | return ret; |
| 129 | } |
| 130 | |
| 131 | static int pt_gpio_remove(struct platform_device *pdev) |
| 132 | { |
| 133 | struct pt_gpio_chip *pt_gpio = platform_get_drvdata(pdev); |
| 134 | |
| 135 | gpiochip_remove(&pt_gpio->gc); |
| 136 | |
| 137 | return 0; |
| 138 | } |
| 139 | |
| 140 | static const struct acpi_device_id pt_gpio_acpi_match[] = { |
| 141 | { "AMDF030", 0 }, |
YD Tseng | ca27379 | 2016-03-17 11:35:57 +0800 | [diff] [blame] | 142 | { "AMDIF030", 0 }, |
YD Tseng | 6057d40 | 2015-10-19 11:07:37 +0800 | [diff] [blame] | 143 | { }, |
| 144 | }; |
| 145 | MODULE_DEVICE_TABLE(acpi, pt_gpio_acpi_match); |
| 146 | |
| 147 | static struct platform_driver pt_gpio_driver = { |
| 148 | .driver = { |
| 149 | .name = "pt-gpio", |
| 150 | .acpi_match_table = ACPI_PTR(pt_gpio_acpi_match), |
| 151 | }, |
| 152 | .probe = pt_gpio_probe, |
| 153 | .remove = pt_gpio_remove, |
| 154 | }; |
| 155 | |
| 156 | module_platform_driver(pt_gpio_driver); |
| 157 | |
| 158 | MODULE_LICENSE("GPL"); |
| 159 | MODULE_AUTHOR("YD Tseng <yd_tseng@asmedia.com.tw>"); |
| 160 | MODULE_DESCRIPTION("AMD Promontory GPIO Driver"); |