/* * AppliedMicro X-Gene SoC GPIO-Standby Driver * * Copyright (c) 2014, Applied Micro Circuits Corporation * Author: Tin Huynh <tnhuynh@apm.com>. * Y Vo <yvo@apm.com>. * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. * * 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. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <linux/module.h> #include <linux/io.h> #include <linux/platform_device.h> #include <linux/of_gpio.h> #include <linux/gpio/driver.h> #include <linux/acpi.h> #include "gpiolib.h" #define XGENE_MAX_GPIO_DS 22 #define XGENE_MAX_GPIO_DS_IRQ 6 #define GPIO_MASK(x) (1U << ((x) % 32)) #define MPA_GPIO_INT_LVL 0x0290 #define MPA_GPIO_OE_ADDR 0x029c #define MPA_GPIO_OUT_ADDR 0x02a0 #define MPA_GPIO_IN_ADDR 0x02a4 #define MPA_GPIO_SEL_LO 0x0294 /** * struct xgene_gpio_sb - GPIO-Standby private data structure. * @gc: memory-mapped GPIO controllers. * @irq: Mapping GPIO pins and interrupt number * nirq: Number of GPIO pins that supports interrupt */ struct xgene_gpio_sb { struct gpio_chip gc; u32 *irq; u32 nirq; }; static void xgene_gpio_set_bit(struct gpio_chip *gc, void __iomem *reg, u32 gpio, int val) { u32 data; data = gc->read_reg(reg); if (val) data |= GPIO_MASK(gpio); else data &= ~GPIO_MASK(gpio); gc->write_reg(reg, data); } static int apm_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio) { struct xgene_gpio_sb *priv = gpiochip_get_data(gc); if (priv->irq[gpio]) return priv->irq[gpio]; return -ENXIO; } static int xgene_gpio_sb_probe(struct platform_device *pdev) { struct xgene_gpio_sb *priv; u32 ret, i; u32 default_lines[] = {0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0D}; struct resource *res; void __iomem *regs; priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); regs = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(regs)) return PTR_ERR(regs); ret = bgpio_init(&priv->gc, &pdev->dev, 4, regs + MPA_GPIO_IN_ADDR, regs + MPA_GPIO_OUT_ADDR, NULL, regs + MPA_GPIO_OE_ADDR, NULL, 0); if (ret) return ret; priv->gc.to_irq = apm_gpio_sb_to_irq; priv->gc.ngpio = XGENE_MAX_GPIO_DS; priv->nirq = XGENE_MAX_GPIO_DS_IRQ; priv->irq = devm_kzalloc(&pdev->dev, sizeof(u32) * XGENE_MAX_GPIO_DS, GFP_KERNEL); if (!priv->irq) return -ENOMEM; for (i = 0; i < priv->nirq; i++) { priv->irq[default_lines[i]] = platform_get_irq(pdev, i); xgene_gpio_set_bit(&priv->gc, regs + MPA_GPIO_SEL_LO, default_lines[i] * 2, 1); xgene_gpio_set_bit(&priv->gc, regs + MPA_GPIO_INT_LVL, i, 1); } platform_set_drvdata(pdev, priv); ret = gpiochip_add_data(&priv->gc, priv); if (ret) dev_err(&pdev->dev, "failed to register X-Gene GPIO Standby driver\n"); else dev_info(&pdev->dev, "X-Gene GPIO Standby driver registered\n"); if (priv->nirq > 0) { /* Register interrupt handlers for gpio signaled acpi events */ acpi_gpiochip_request_interrupts(&priv->gc); } return ret; } static int xgene_gpio_sb_remove(struct platform_device *pdev) { struct xgene_gpio_sb *priv = platform_get_drvdata(pdev); if (priv->nirq > 0) { acpi_gpiochip_free_interrupts(&priv->gc); } gpiochip_remove(&priv->gc); return 0; } static const struct of_device_id xgene_gpio_sb_of_match[] = { {.compatible = "apm,xgene-gpio-sb", }, {}, }; MODULE_DEVICE_TABLE(of, xgene_gpio_sb_of_match); #ifdef CONFIG_ACPI static const struct acpi_device_id xgene_gpio_sb_acpi_match[] = { {"APMC0D15", 0}, {}, }; MODULE_DEVICE_TABLE(acpi, xgene_gpio_sb_acpi_match); #endif static struct platform_driver xgene_gpio_sb_driver = { .driver = { .name = "xgene-gpio-sb", .of_match_table = xgene_gpio_sb_of_match, .acpi_match_table = ACPI_PTR(xgene_gpio_sb_acpi_match), }, .probe = xgene_gpio_sb_probe, .remove = xgene_gpio_sb_remove, }; module_platform_driver(xgene_gpio_sb_driver); MODULE_AUTHOR("AppliedMicro"); MODULE_DESCRIPTION("APM X-Gene GPIO Standby driver"); MODULE_LICENSE("GPL");