1 // SPDX-License-Identifier: GPL-2.0 2 /** 3 * dwc3-keystone.c - Keystone Specific Glue layer 4 * 5 * Copyright (C) 2010-2013 Texas Instruments Incorporated - http://www.ti.com 6 * 7 * Author: WingMan Kwok <w-kwok2@ti.com> 8 */ 9 10 #include <linux/module.h> 11 #include <linux/kernel.h> 12 #include <linux/interrupt.h> 13 #include <linux/platform_device.h> 14 #include <linux/dma-mapping.h> 15 #include <linux/io.h> 16 #include <linux/of_platform.h> 17 #include <linux/pm_runtime.h> 18 19 /* USBSS register offsets */ 20 #define USBSS_REVISION 0x0000 21 #define USBSS_SYSCONFIG 0x0010 22 #define USBSS_IRQ_EOI 0x0018 23 #define USBSS_IRQSTATUS_RAW_0 0x0020 24 #define USBSS_IRQSTATUS_0 0x0024 25 #define USBSS_IRQENABLE_SET_0 0x0028 26 #define USBSS_IRQENABLE_CLR_0 0x002c 27 28 /* IRQ register bits */ 29 #define USBSS_IRQ_EOI_LINE(n) BIT(n) 30 #define USBSS_IRQ_EVENT_ST BIT(0) 31 #define USBSS_IRQ_COREIRQ_EN BIT(0) 32 #define USBSS_IRQ_COREIRQ_CLR BIT(0) 33 34 struct dwc3_keystone { 35 struct device *dev; 36 void __iomem *usbss; 37 }; 38 39 static inline u32 kdwc3_readl(void __iomem *base, u32 offset) 40 { 41 return readl(base + offset); 42 } 43 44 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value) 45 { 46 writel(value, base + offset); 47 } 48 49 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc) 50 { 51 u32 val; 52 53 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0); 54 val |= USBSS_IRQ_COREIRQ_EN; 55 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val); 56 } 57 58 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc) 59 { 60 u32 val; 61 62 val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0); 63 val &= ~USBSS_IRQ_COREIRQ_EN; 64 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val); 65 } 66 67 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc) 68 { 69 struct dwc3_keystone *kdwc = _kdwc; 70 71 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR); 72 kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST); 73 kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN); 74 kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0)); 75 76 return IRQ_HANDLED; 77 } 78 79 static int kdwc3_probe(struct platform_device *pdev) 80 { 81 struct device *dev = &pdev->dev; 82 struct device_node *node = pdev->dev.of_node; 83 struct dwc3_keystone *kdwc; 84 int error, irq; 85 86 kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL); 87 if (!kdwc) 88 return -ENOMEM; 89 90 platform_set_drvdata(pdev, kdwc); 91 92 kdwc->dev = dev; 93 94 kdwc->usbss = devm_platform_ioremap_resource(pdev, 0); 95 if (IS_ERR(kdwc->usbss)) 96 return PTR_ERR(kdwc->usbss); 97 98 pm_runtime_enable(kdwc->dev); 99 100 error = pm_runtime_get_sync(kdwc->dev); 101 if (error < 0) { 102 dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n", 103 error); 104 goto err_irq; 105 } 106 107 /* IRQ processing not required currently for AM65 */ 108 if (of_device_is_compatible(node, "ti,am654-dwc3")) 109 goto skip_irq; 110 111 irq = platform_get_irq(pdev, 0); 112 if (irq < 0) { 113 error = irq; 114 goto err_irq; 115 } 116 117 error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED, 118 dev_name(dev), kdwc); 119 if (error) { 120 dev_err(dev, "failed to request IRQ #%d --> %d\n", 121 irq, error); 122 goto err_irq; 123 } 124 125 kdwc3_enable_irqs(kdwc); 126 127 skip_irq: 128 error = of_platform_populate(node, NULL, NULL, dev); 129 if (error) { 130 dev_err(&pdev->dev, "failed to create dwc3 core\n"); 131 goto err_core; 132 } 133 134 return 0; 135 136 err_core: 137 kdwc3_disable_irqs(kdwc); 138 err_irq: 139 pm_runtime_put_sync(kdwc->dev); 140 pm_runtime_disable(kdwc->dev); 141 142 return error; 143 } 144 145 static int kdwc3_remove_core(struct device *dev, void *c) 146 { 147 struct platform_device *pdev = to_platform_device(dev); 148 149 platform_device_unregister(pdev); 150 151 return 0; 152 } 153 154 static int kdwc3_remove(struct platform_device *pdev) 155 { 156 struct dwc3_keystone *kdwc = platform_get_drvdata(pdev); 157 struct device_node *node = pdev->dev.of_node; 158 159 if (!of_device_is_compatible(node, "ti,am654-dwc3")) 160 kdwc3_disable_irqs(kdwc); 161 162 device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core); 163 pm_runtime_put_sync(kdwc->dev); 164 pm_runtime_disable(kdwc->dev); 165 166 platform_set_drvdata(pdev, NULL); 167 168 return 0; 169 } 170 171 static const struct of_device_id kdwc3_of_match[] = { 172 { .compatible = "ti,keystone-dwc3", }, 173 { .compatible = "ti,am654-dwc3" }, 174 {}, 175 }; 176 MODULE_DEVICE_TABLE(of, kdwc3_of_match); 177 178 static struct platform_driver kdwc3_driver = { 179 .probe = kdwc3_probe, 180 .remove = kdwc3_remove, 181 .driver = { 182 .name = "keystone-dwc3", 183 .of_match_table = kdwc3_of_match, 184 }, 185 }; 186 187 module_platform_driver(kdwc3_driver); 188 189 MODULE_ALIAS("platform:keystone-dwc3"); 190 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>"); 191 MODULE_LICENSE("GPL v2"); 192 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer"); 193