1 /** 2 * dwc3-keystone.c - Keystone Specific Glue layer 3 * 4 * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com 5 * 6 * Author: WingMan Kwok <w-kwok2@ti.com> 7 * 8 * This program is free software: you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 of 10 * the License as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 */ 17 18 #include <linux/module.h> 19 #include <linux/kernel.h> 20 #include <linux/interrupt.h> 21 #include <linux/platform_device.h> 22 #include <linux/dma-mapping.h> 23 #include <linux/io.h> 24 #include <linux/of_platform.h> 25 #include <linux/pm_runtime.h> 26 27 /* USBSS register offsets */ 28 #define USBSS_REVISION 0x0000 29 #define USBSS_SYSCONFIG 0x0010 30 #define USBSS_IRQ_EOI 0x0018 31 #define USBSS_IRQSTATUS_RAW_0 0x0020 32 #define USBSS_IRQSTATUS_0 0x0024 33 #define USBSS_IRQENABLE_SET_0 0x0028 34 #define USBSS_IRQENABLE_CLR_0 0x002c 35 36 /* IRQ register bits */ 37 #define USBSS_IRQ_EOI_LINE(n) BIT(n) 38 #define USBSS_IRQ_EVENT_ST BIT(0) 39 #define USBSS_IRQ_COREIRQ_EN BIT(0) 40 #define USBSS_IRQ_COREIRQ_CLR BIT(0) 41 42 struct dwc3_keystone { 43 struct device *dev; 44 void __iomem *usbss; 45 }; 46 47 static inline u32 kdwc3_readl(void __iomem *base, u32 offset) 48 { 49 return readl(base + offset); 50 } 51 52 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value) 53 { 54 writel(value, base + offset); 55 } 56 57 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc) 58 { 59 u32 val; 60 61 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0); 62 val |= USBSS_IRQ_COREIRQ_EN; 63 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val); 64 } 65 66 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc) 67 { 68 u32 val; 69 70 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0); 71 val &= ~USBSS_IRQ_COREIRQ_EN; 72 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val); 73 } 74 75 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc) 76 { 77 struct dwc3_keystone *kdwc = _kdwc; 78 79 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR); 80 kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST); 81 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN); 82 kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0)); 83 84 return IRQ_HANDLED; 85 } 86 87 static int kdwc3_probe(struct platform_device *pdev) 88 { 89 struct device *dev = &pdev->dev; 90 struct device_node *node = pdev->dev.of_node; 91 struct dwc3_keystone *kdwc; 92 struct resource *res; 93 int error, irq; 94 95 kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL); 96 if (!kdwc) 97 return -ENOMEM; 98 99 platform_set_drvdata(pdev, kdwc); 100 101 kdwc->dev = dev; 102 103 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 104 kdwc->usbss = devm_ioremap_resource(dev, res); 105 if (IS_ERR(kdwc->usbss)) 106 return PTR_ERR(kdwc->usbss); 107 108 pm_runtime_enable(kdwc->dev); 109 110 error = pm_runtime_get_sync(kdwc->dev); 111 if (error < 0) { 112 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n", 113 error); 114 goto err_irq; 115 } 116 117 irq = platform_get_irq(pdev, 0); 118 if (irq < 0) { 119 dev_err(&pdev->dev, "missing irq\n"); 120 error = irq; 121 goto err_irq; 122 } 123 124 error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED, 125 dev_name(dev), kdwc); 126 if (error) { 127 dev_err(dev, "failed to request IRQ #%d --> %d\n", 128 irq, error); 129 goto err_irq; 130 } 131 132 kdwc3_enable_irqs(kdwc); 133 134 error = of_platform_populate(node, NULL, NULL, dev); 135 if (error) { 136 dev_err(&pdev->dev, "failed to create dwc3 core\n"); 137 goto err_core; 138 } 139 140 return 0; 141 142 err_core: 143 kdwc3_disable_irqs(kdwc); 144 err_irq: 145 pm_runtime_put_sync(kdwc->dev); 146 pm_runtime_disable(kdwc->dev); 147 148 return error; 149 } 150 151 static int kdwc3_remove_core(struct device *dev, void *c) 152 { 153 struct platform_device *pdev = to_platform_device(dev); 154 155 platform_device_unregister(pdev); 156 157 return 0; 158 } 159 160 static int kdwc3_remove(struct platform_device *pdev) 161 { 162 struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); 163 164 kdwc3_disable_irqs(kdwc); 165 device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core); 166 pm_runtime_put_sync(kdwc->dev); 167 pm_runtime_disable(kdwc->dev); 168 169 platform_set_drvdata(pdev, NULL); 170 171 return 0; 172 } 173 174 static const struct of_device_id kdwc3_of_match[] = { 175 { .compatible = "ti,keystone-dwc3", }, 176 {}, 177 }; 178 MODULE_DEVICE_TABLE(of, kdwc3_of_match); 179 180 static struct platform_driver kdwc3_driver = { 181 .probe = kdwc3_probe, 182 .remove = kdwc3_remove, 183 .driver = { 184 .name = "keystone-dwc3", 185 .of_match_table = kdwc3_of_match, 186 }, 187 }; 188 189 module_platform_driver(kdwc3_driver); 190 191 MODULE_ALIAS("platform:keystone-dwc3"); 192 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>"); 193 MODULE_LICENSE("GPL v2"); 194 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer"); 195