usb/dwc3/dwc3-keystone.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * dwc3-keystone.c - Keystone Specific Glue layer
0004  *
0005  * Copyright (C) 2010-2013 Texas Instruments Incorporated - https://www.ti.com
0006  *
0007  * Author: WingMan Kwok <w-kwok2@ti.com>
0008  */
0009
0010 #include <linux/module.h>
0011 #include <linux/kernel.h>
0012 #include <linux/interrupt.h>
0013 #include <linux/platform_device.h>
0014 #include <linux/dma-mapping.h>
0015 #include <linux/io.h>
0016 #include <linux/of_platform.h>
0017 #include <linux/phy/phy.h>
0018 #include <linux/pm_runtime.h>
0019
0020 /* USBSS register offsets */
0021 #define USBSS_REVISION      0x0000
0022 #define USBSS_SYSCONFIG     0x0010
0023 #define USBSS_IRQ_EOI       0x0018
0024 #define USBSS_IRQSTATUS_RAW_0   0x0020
0025 #define USBSS_IRQSTATUS_0   0x0024
0026 #define USBSS_IRQENABLE_SET_0   0x0028
0027 #define USBSS_IRQENABLE_CLR_0   0x002c
0028
0029 /* IRQ register bits */
0030 #define USBSS_IRQ_EOI_LINE(n)   BIT(n)
0031 #define USBSS_IRQ_EVENT_ST  BIT(0)
0032 #define USBSS_IRQ_COREIRQ_EN    BIT(0)
0033 #define USBSS_IRQ_COREIRQ_CLR   BIT(0)
0034
0035 struct dwc3_keystone {
0036     struct device           *dev;
0037     void __iomem            *usbss;
0038     struct phy          *usb3_phy;
0039 };
0040
0041 static inline u32 kdwc3_readl(void __iomem *base, u32 offset)
0042 {
0043     return readl(base + offset);
0044 }
0045
0046 static inline void kdwc3_writel(void __iomem *base, u32 offset, u32 value)
0047 {
0048     writel(value, base + offset);
0049 }
0050
0051 static void kdwc3_enable_irqs(struct dwc3_keystone *kdwc)
0052 {
0053     u32 val;
0054
0055     val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
0056     val |= USBSS_IRQ_COREIRQ_EN;
0057     kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
0058 }
0059
0060 static void kdwc3_disable_irqs(struct dwc3_keystone *kdwc)
0061 {
0062     u32 val;
0063
0064     val = kdwc3_readl(kdwc->usbss, USBSS_IRQENABLE_SET_0);
0065     val &= ~USBSS_IRQ_COREIRQ_EN;
0066     kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, val);
0067 }
0068
0069 static irqreturn_t dwc3_keystone_interrupt(int irq, void *_kdwc)
0070 {
0071     struct dwc3_keystone    *kdwc = _kdwc;
0072
0073     kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_CLR_0, USBSS_IRQ_COREIRQ_CLR);
0074     kdwc3_writel(kdwc->usbss, USBSS_IRQSTATUS_0, USBSS_IRQ_EVENT_ST);
0075     kdwc3_writel(kdwc->usbss, USBSS_IRQENABLE_SET_0, USBSS_IRQ_COREIRQ_EN);
0076     kdwc3_writel(kdwc->usbss, USBSS_IRQ_EOI, USBSS_IRQ_EOI_LINE(0));
0077
0078     return IRQ_HANDLED;
0079 }
0080
0081 static int kdwc3_probe(struct platform_device *pdev)
0082 {
0083     struct device       *dev = &pdev->dev;
0084     struct device_node  *node = pdev->dev.of_node;
0085     struct dwc3_keystone    *kdwc;
0086     int         error, irq;
0087
0088     kdwc = devm_kzalloc(dev, sizeof(*kdwc), GFP_KERNEL);
0089     if (!kdwc)
0090         return -ENOMEM;
0091
0092     platform_set_drvdata(pdev, kdwc);
0093
0094     kdwc->dev = dev;
0095
0096     kdwc->usbss = devm_platform_ioremap_resource(pdev, 0);
0097     if (IS_ERR(kdwc->usbss))
0098         return PTR_ERR(kdwc->usbss);
0099
0100     /* PSC dependency on AM65 needs SERDES0 to be powered before USB0 */
0101     kdwc->usb3_phy = devm_phy_optional_get(dev, "usb3-phy");
0102     if (IS_ERR(kdwc->usb3_phy))
0103         return dev_err_probe(dev, PTR_ERR(kdwc->usb3_phy), "couldn't get usb3 phy\n");
0104
0105     phy_pm_runtime_get_sync(kdwc->usb3_phy);
0106
0107     error = phy_reset(kdwc->usb3_phy);
0108     if (error < 0) {
0109         dev_err(dev, "usb3 phy reset failed: %d\n", error);
0110         return error;
0111     }
0112
0113     error = phy_init(kdwc->usb3_phy);
0114     if (error < 0) {
0115         dev_err(dev, "usb3 phy init failed: %d\n", error);
0116         return error;
0117     }
0118
0119     error = phy_power_on(kdwc->usb3_phy);
0120     if (error < 0) {
0121         dev_err(dev, "usb3 phy power on failed: %d\n", error);
0122         phy_exit(kdwc->usb3_phy);
0123         return error;
0124     }
0125
0126     pm_runtime_enable(kdwc->dev);
0127     error = pm_runtime_get_sync(kdwc->dev);
0128     if (error < 0) {
0129         dev_err(kdwc->dev, "pm_runtime_get_sync failed, error %d\n",
0130             error);
0131         goto err_irq;
0132     }
0133
0134     /* IRQ processing not required currently for AM65 */
0135     if (of_device_is_compatible(node, "ti,am654-dwc3"))
0136         goto skip_irq;
0137
0138     irq = platform_get_irq(pdev, 0);
0139     if (irq < 0) {
0140         error = irq;
0141         goto err_irq;
0142     }
0143
0144     error = devm_request_irq(dev, irq, dwc3_keystone_interrupt, IRQF_SHARED,
0145             dev_name(dev), kdwc);
0146     if (error) {
0147         dev_err(dev, "failed to request IRQ #%d --> %d\n",
0148                 irq, error);
0149         goto err_irq;
0150     }
0151
0152     kdwc3_enable_irqs(kdwc);
0153
0154 skip_irq:
0155     error = of_platform_populate(node, NULL, NULL, dev);
0156     if (error) {
0157         dev_err(&pdev->dev, "failed to create dwc3 core\n");
0158         goto err_core;
0159     }
0160
0161     return 0;
0162
0163 err_core:
0164     kdwc3_disable_irqs(kdwc);
0165 err_irq:
0166     pm_runtime_put_sync(kdwc->dev);
0167     pm_runtime_disable(kdwc->dev);
0168     phy_power_off(kdwc->usb3_phy);
0169     phy_exit(kdwc->usb3_phy);
0170     phy_pm_runtime_put_sync(kdwc->usb3_phy);
0171
0172     return error;
0173 }
0174
0175 static int kdwc3_remove_core(struct device *dev, void *c)
0176 {
0177     struct platform_device *pdev = to_platform_device(dev);
0178
0179     platform_device_unregister(pdev);
0180
0181     return 0;
0182 }
0183
0184 static int kdwc3_remove(struct platform_device *pdev)
0185 {
0186     struct dwc3_keystone *kdwc = platform_get_drvdata(pdev);
0187     struct device_node *node = pdev->dev.of_node;
0188
0189     if (!of_device_is_compatible(node, "ti,am654-dwc3"))
0190         kdwc3_disable_irqs(kdwc);
0191
0192     device_for_each_child(&pdev->dev, NULL, kdwc3_remove_core);
0193     pm_runtime_put_sync(kdwc->dev);
0194     pm_runtime_disable(kdwc->dev);
0195
0196     phy_power_off(kdwc->usb3_phy);
0197     phy_exit(kdwc->usb3_phy);
0198     phy_pm_runtime_put_sync(kdwc->usb3_phy);
0199
0200     platform_set_drvdata(pdev, NULL);
0201
0202     return 0;
0203 }
0204
0205 static const struct of_device_id kdwc3_of_match[] = {
0206     { .compatible = "ti,keystone-dwc3", },
0207     { .compatible = "ti,am654-dwc3" },
0208     {},
0209 };
0210 MODULE_DEVICE_TABLE(of, kdwc3_of_match);
0211
0212 static struct platform_driver kdwc3_driver = {
0213     .probe      = kdwc3_probe,
0214     .remove     = kdwc3_remove,
0215     .driver     = {
0216         .name   = "keystone-dwc3",
0217         .of_match_table = kdwc3_of_match,
0218     },
0219 };
0220
0221 module_platform_driver(kdwc3_driver);
0222
0223 MODULE_ALIAS("platform:keystone-dwc3");
0224 MODULE_AUTHOR("WingMan Kwok <w-kwok2@ti.com>");
0225 MODULE_LICENSE("GPL v2");
0226 MODULE_DESCRIPTION("DesignWare USB3 KEYSTONE Glue Layer");