1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * OMAP OTG controller driver 4 * 5 * Based on code from tahvo-usb.c and isp1301_omap.c drivers. 6 * 7 * Copyright (C) 2005-2006 Nokia Corporation 8 * Copyright (C) 2004 Texas Instruments 9 * Copyright (C) 2004 David Brownell 10 */ 11 12 #include <linux/io.h> 13 #include <linux/err.h> 14 #include <linux/extcon.h> 15 #include <linux/kernel.h> 16 #include <linux/module.h> 17 #include <linux/interrupt.h> 18 #include <linux/platform_device.h> 19 #include <linux/platform_data/usb-omap1.h> 20 21 struct otg_device { 22 void __iomem *base; 23 bool id; 24 bool vbus; 25 struct extcon_dev *extcon; 26 struct notifier_block vbus_nb; 27 struct notifier_block id_nb; 28 }; 29 30 #define OMAP_OTG_CTRL 0x0c 31 #define OMAP_OTG_ASESSVLD (1 << 20) 32 #define OMAP_OTG_BSESSEND (1 << 19) 33 #define OMAP_OTG_BSESSVLD (1 << 18) 34 #define OMAP_OTG_VBUSVLD (1 << 17) 35 #define OMAP_OTG_ID (1 << 16) 36 #define OMAP_OTG_XCEIV_OUTPUTS \ 37 (OMAP_OTG_ASESSVLD | OMAP_OTG_BSESSEND | OMAP_OTG_BSESSVLD | \ 38 OMAP_OTG_VBUSVLD | OMAP_OTG_ID) 39 40 static void omap_otg_ctrl(struct otg_device *otg_dev, u32 outputs) 41 { 42 u32 l; 43 44 l = readl(otg_dev->base + OMAP_OTG_CTRL); 45 l &= ~OMAP_OTG_XCEIV_OUTPUTS; 46 l |= outputs; 47 writel(l, otg_dev->base + OMAP_OTG_CTRL); 48 } 49 50 static void omap_otg_set_mode(struct otg_device *otg_dev) 51 { 52 if (!otg_dev->id && otg_dev->vbus) 53 /* Set B-session valid. */ 54 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSVLD); 55 else if (otg_dev->vbus) 56 /* Set A-session valid. */ 57 omap_otg_ctrl(otg_dev, OMAP_OTG_ASESSVLD); 58 else if (!otg_dev->id) 59 /* Set B-session end to indicate no VBUS. */ 60 omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSEND); 61 } 62 63 static int omap_otg_id_notifier(struct notifier_block *nb, 64 unsigned long event, void *ptr) 65 { 66 struct otg_device *otg_dev = container_of(nb, struct otg_device, id_nb); 67 68 otg_dev->id = event; 69 omap_otg_set_mode(otg_dev); 70 71 return NOTIFY_DONE; 72 } 73 74 static int omap_otg_vbus_notifier(struct notifier_block *nb, 75 unsigned long event, void *ptr) 76 { 77 struct otg_device *otg_dev = container_of(nb, struct otg_device, 78 vbus_nb); 79 80 otg_dev->vbus = event; 81 omap_otg_set_mode(otg_dev); 82 83 return NOTIFY_DONE; 84 } 85 86 static int omap_otg_probe(struct platform_device *pdev) 87 { 88 const struct omap_usb_config *config = pdev->dev.platform_data; 89 struct otg_device *otg_dev; 90 struct extcon_dev *extcon; 91 int ret; 92 u32 rev; 93 94 if (!config || !config->extcon) 95 return -ENODEV; 96 97 extcon = extcon_get_extcon_dev(config->extcon); 98 if (!extcon) 99 return -EPROBE_DEFER; 100 101 otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL); 102 if (!otg_dev) 103 return -ENOMEM; 104 105 otg_dev->base = devm_ioremap_resource(&pdev->dev, &pdev->resource[0]); 106 if (IS_ERR(otg_dev->base)) 107 return PTR_ERR(otg_dev->base); 108 109 otg_dev->extcon = extcon; 110 otg_dev->id_nb.notifier_call = omap_otg_id_notifier; 111 otg_dev->vbus_nb.notifier_call = omap_otg_vbus_notifier; 112 113 ret = devm_extcon_register_notifier(&pdev->dev, extcon, 114 EXTCON_USB_HOST, &otg_dev->id_nb); 115 if (ret) 116 return ret; 117 118 ret = devm_extcon_register_notifier(&pdev->dev, extcon, 119 EXTCON_USB, &otg_dev->vbus_nb); 120 if (ret) { 121 return ret; 122 } 123 124 otg_dev->id = extcon_get_state(extcon, EXTCON_USB_HOST); 125 otg_dev->vbus = extcon_get_state(extcon, EXTCON_USB); 126 omap_otg_set_mode(otg_dev); 127 128 rev = readl(otg_dev->base); 129 130 dev_info(&pdev->dev, 131 "OMAP USB OTG controller rev %d.%d (%s, id=%d, vbus=%d)\n", 132 (rev >> 4) & 0xf, rev & 0xf, config->extcon, otg_dev->id, 133 otg_dev->vbus); 134 135 platform_set_drvdata(pdev, otg_dev); 136 137 return 0; 138 } 139 140 static struct platform_driver omap_otg_driver = { 141 .probe = omap_otg_probe, 142 .driver = { 143 .name = "omap_otg", 144 }, 145 }; 146 module_platform_driver(omap_otg_driver); 147 148 MODULE_DESCRIPTION("OMAP USB OTG controller driver"); 149 MODULE_LICENSE("GPL"); 150 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>"); 151