/** * dwc3-keystone.c - Keystone Specific Glue layer * * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com * * Author: WingMan Kwok <w-kwok2@ti.com> * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 of * the License as published by the Free Software Foundation. * * 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. */ #include <linux/clk.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/interrupt.h> #include <linux/platform_device.h> #include <linux/dma-mapping.h> #include <linux/io.h> #include <linux/of_platform.h> /* USBSS register offsets */ #define USBSS_REVISION 0x0000 #define USBSS_SYSCONFIG 0x0010 #define USBSS_IRQ_EOI 0x0018 #define USBSS_IRQSTATUS_RAW_0 0x0020 #define USBSS_IRQSTATUS_0 0x0024 #define USBSS_IRQENABLE_SET_0 0x0028 #define USBSS_IRQENABLE_CLR_0 0x002c /* IRQ register bits */ #define USBSS_IRQ_EOI_LINE(n) BIT(n) #define USBSS_IRQ_EVENT_ST BIT(0) #define USBSS_IRQ_COREIRQ_EN BIT(0) #define USBSS_IRQ_COREIRQ_CLR BIT(0) struct dwc3_keystone { struct device *dev; struct clk *clk; void __iomem *usbss; }; static inline u32 kdwc3_readl(void __iomem *base, u32 offset) { return readl(base + offset); } static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value) { writel(value, base + offset); } static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc) { u32 val; val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0); val |= USBSS_IRQ_COREIRQ_EN; kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val); } static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc) { u32 val; val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0); val &= ~USBSS_IRQ_COREIRQ_EN; kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val); } static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc) { struct dwc3_keystone *kdwc = _kdwc; kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR); kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST); kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN); kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0)); return IRQ_HANDLED; } static int kdwc3_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *node = pdev->dev.of_node; struct dwc3_keystone *kdwc; struct resource *res; int error, irq; kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL); if (!kdwc) return -ENOMEM; platform_set_drvdata(pdev, kdwc); kdwc->dev = dev; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); kdwc->usbss = devm_ioremap_resource(dev, res); if (IS_ERR(kdwc->usbss)) return PTR_ERR(kdwc->usbss); kdwc->clk = devm_clk_get(kdwc->dev, "usb"); error = clk_prepare_enable(kdwc->clk); if (error < 0) { dev_err(kdwc->dev, "unable to enable usb clock, error %d\n", error); return error; } irq = platform_get_irq(pdev, 0); if (irq < 0) { dev_err(&pdev->dev, "missing irq\n"); error = irq; goto err_irq; } error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED, dev_name(dev), kdwc); if (error) { dev_err(dev, "failed to request IRQ #%d --> %d\n", irq, error); goto err_irq; } kdwc3_enable_irqs(kdwc); error = of_platform_populate(node, NULL, NULL, dev); if (error) { dev_err(&pdev->dev, "failed to create dwc3 core\n"); goto err_core; } return 0; err_core: kdwc3_disable_irqs(kdwc); err_irq: clk_disable_unprepare(kdwc->clk); return error; } static int kdwc3_remove_core(struct device *dev, void *c) { struct platform_device *pdev = to_platform_device(dev); platform_device_unregister(pdev); return 0; } static int kdwc3_remove(struct platform_device *pdev) { struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); kdwc3_disable_irqs(kdwc); device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core); clk_disable_unprepare(kdwc->clk); platform_set_drvdata(pdev, NULL); return 0; } static const struct of_device_id kdwc3_of_match[] = { { .compatible = "ti,keystone-dwc3", }, {}, }; MODULE_DEVICE_TABLE(of, kdwc3_of_match); static struct platform_driver kdwc3_driver = { .probe = kdwc3_probe, .remove = kdwc3_remove, .driver = { .name = "keystone-dwc3", .of_match_table = kdwc3_of_match, }, }; module_platform_driver(kdwc3_driver); MODULE_ALIAS("platform:keystone-dwc3"); MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>"); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");