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Release 4.14 drivers/gpio/gpio-amdpt.c

Directory: drivers/gpio
/*
 * AMD Promontory GPIO driver
 *
 * Copyright (C) 2015 ASMedia Technology Inc.
 * Author: YD Tseng <yd_tseng@asmedia.com.tw>
 *
 * 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.
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gpio/driver.h>
#include <linux/spinlock.h>
#include <linux/acpi.h>
#include <linux/platform_device.h>


#define PT_TOTAL_GPIO 8

/* PCI-E MMIO register offsets */

#define PT_DIRECTION_REG   0x00

#define PT_INPUTDATA_REG   0x04

#define PT_OUTPUTDATA_REG  0x08

#define PT_CLOCKRATE_REG   0x0C

#define PT_SYNC_REG        0x28


struct pt_gpio_chip {
	
struct gpio_chip         gc;
	
void __iomem             *reg_base;
};


static int pt_gpio_request(struct gpio_chip *gc, unsigned offset) { struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc); unsigned long flags; u32 using_pins; dev_dbg(gc->parent, "pt_gpio_request offset=%x\n", offset); spin_lock_irqsave(&gc->bgpio_lock, flags); using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG); if (using_pins & BIT(offset)) { dev_warn(gc->parent, "PT GPIO pin %x reconfigured\n", offset); spin_unlock_irqrestore(&gc->bgpio_lock, flags); return -EINVAL; } writel(using_pins | BIT(offset), pt_gpio->reg_base + PT_SYNC_REG); spin_unlock_irqrestore(&gc->bgpio_lock, flags); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
YD Tseng7961.72%125.00%
Axel Lin4736.72%125.00%
Linus Walleij21.56%250.00%
Total128100.00%4100.00%


static void pt_gpio_free(struct gpio_chip *gc, unsigned offset) { struct pt_gpio_chip *pt_gpio = gpiochip_get_data(gc); unsigned long flags; u32 using_pins; spin_lock_irqsave(&gc->bgpio_lock, flags); using_pins = readl(pt_gpio->reg_base + PT_SYNC_REG); using_pins &= ~BIT(offset); writel(using_pins, pt_gpio->reg_base + PT_SYNC_REG); spin_unlock_irqrestore(&gc->bgpio_lock, flags); dev_dbg(gc->parent, "pt_gpio_free offset=%x\n", offset); }

Contributors

PersonTokensPropCommitsCommitProp
YD Tseng7076.09%133.33%
Axel Lin2122.83%133.33%
Linus Walleij11.09%133.33%
Total92100.00%3100.00%


static int pt_gpio_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct acpi_device *acpi_dev; acpi_handle handle = ACPI_HANDLE(dev); struct pt_gpio_chip *pt_gpio; struct resource *res_mem; int ret = 0; if (acpi_bus_get_device(handle, &acpi_dev)) { dev_err(dev, "PT GPIO device node not found\n"); return -ENODEV; } pt_gpio = devm_kzalloc(dev, sizeof(struct pt_gpio_chip), GFP_KERNEL); if (!pt_gpio) return -ENOMEM; res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res_mem) { dev_err(&pdev->dev, "Failed to get MMIO resource for PT GPIO.\n"); return -EINVAL; } pt_gpio->reg_base = devm_ioremap_resource(dev, res_mem); if (IS_ERR(pt_gpio->reg_base)) { dev_err(&pdev->dev, "Failed to map MMIO resource for PT GPIO.\n"); return PTR_ERR(pt_gpio->reg_base); } ret = bgpio_init(&pt_gpio->gc, dev, 4, pt_gpio->reg_base + PT_INPUTDATA_REG, pt_gpio->reg_base + PT_OUTPUTDATA_REG, NULL, pt_gpio->reg_base + PT_DIRECTION_REG, NULL, BGPIOF_READ_OUTPUT_REG_SET); if (ret) { dev_err(&pdev->dev, "bgpio_init failed\n"); return ret; } pt_gpio->gc.owner = THIS_MODULE; pt_gpio->gc.request = pt_gpio_request; pt_gpio->gc.free = pt_gpio_free; pt_gpio->gc.ngpio = PT_TOTAL_GPIO; #if defined(CONFIG_OF_GPIO) pt_gpio->gc.of_node = pdev->dev.of_node; #endif ret = gpiochip_add_data(&pt_gpio->gc, pt_gpio); if (ret) { dev_err(&pdev->dev, "Failed to register GPIO lib\n"); return ret; } platform_set_drvdata(pdev, pt_gpio); /* initialize register setting */ writel(0, pt_gpio->reg_base + PT_SYNC_REG); writel(0, pt_gpio->reg_base + PT_CLOCKRATE_REG); dev_dbg(&pdev->dev, "PT GPIO driver loaded\n"); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
YD Tseng30085.47%133.33%
Axel Lin4813.68%133.33%
Linus Walleij30.85%133.33%
Total351100.00%3100.00%


static int pt_gpio_remove(struct platform_device *pdev) { struct pt_gpio_chip *pt_gpio = platform_get_drvdata(pdev); gpiochip_remove(&pt_gpio->gc); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
YD Tseng32100.00%1100.00%
Total32100.00%1100.00%

static const struct acpi_device_id pt_gpio_acpi_match[] = { { "AMDF030", 0 }, { "AMDIF030", 0 }, { }, }; MODULE_DEVICE_TABLE(acpi, pt_gpio_acpi_match); static struct platform_driver pt_gpio_driver = { .driver = { .name = "pt-gpio", .acpi_match_table = ACPI_PTR(pt_gpio_acpi_match), }, .probe = pt_gpio_probe, .remove = pt_gpio_remove, }; module_platform_driver(pt_gpio_driver); MODULE_LICENSE("GPL"); MODULE_AUTHOR("YD Tseng <yd_tseng@asmedia.com.tw>"); MODULE_DESCRIPTION("AMD Promontory GPIO Driver");

Overall Contributors

PersonTokensPropCommitsCommitProp
YD Tseng62383.51%240.00%
Axel Lin11715.68%120.00%
Linus Walleij60.80%240.00%
Total746100.00%5100.00%
Directory: drivers/gpio
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