1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Cadence USBSS PCI Glue driver
4  *
5  * Copyright (C) 2018-2019 Cadence.
6  *
7  * Author: Pawel Laszczak <pawell@cadence.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/pci.h>
13 #include <linux/platform_device.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/slab.h>
16 
17 struct cdns3_wrap {
18 	struct platform_device *plat_dev;
19 	struct resource dev_res[6];
20 	int devfn;
21 };
22 
23 #define RES_IRQ_HOST_ID		0
24 #define RES_IRQ_PERIPHERAL_ID	1
25 #define RES_IRQ_OTG_ID		2
26 #define RES_HOST_ID		3
27 #define RES_DEV_ID		4
28 #define RES_DRD_ID		5
29 
30 #define PCI_BAR_HOST		0
31 #define PCI_BAR_DEV		2
32 #define PCI_BAR_OTG		0
33 
34 #define PCI_DEV_FN_HOST_DEVICE	0
35 #define PCI_DEV_FN_OTG		1
36 
37 #define PCI_DRIVER_NAME		"cdns3-pci-usbss"
38 #define PLAT_DRIVER_NAME	"cdns-usb3"
39 
40 #define CDNS_VENDOR_ID		0x17cd
41 #define CDNS_DEVICE_ID		0x0100
42 
cdns3_get_second_fun(struct pci_dev * pdev)43 static struct pci_dev *cdns3_get_second_fun(struct pci_dev *pdev)
44 {
45 	struct pci_dev *func;
46 
47 	/*
48 	 * Gets the second function.
49 	 * It's little tricky, but this platform has two function.
50 	 * The fist keeps resources for Host/Device while the second
51 	 * keeps resources for DRD/OTG.
52 	 */
53 	func = pci_get_device(pdev->vendor, pdev->device, NULL);
54 	if (unlikely(!func))
55 		return NULL;
56 
57 	if (func->devfn == pdev->devfn) {
58 		func = pci_get_device(pdev->vendor, pdev->device, func);
59 		if (unlikely(!func))
60 			return NULL;
61 	}
62 
63 	return func;
64 }
65 
cdns3_pci_probe(struct pci_dev * pdev,const struct pci_device_id * id)66 static int cdns3_pci_probe(struct pci_dev *pdev,
67 			   const struct pci_device_id *id)
68 {
69 	struct platform_device_info plat_info;
70 	struct cdns3_wrap *wrap;
71 	struct resource *res;
72 	struct pci_dev *func;
73 	int err;
74 
75 	/*
76 	 * for GADGET/HOST PCI (devfn) function number is 0,
77 	 * for OTG PCI (devfn) function number is 1
78 	 */
79 	if (!id || (pdev->devfn != PCI_DEV_FN_HOST_DEVICE &&
80 		    pdev->devfn != PCI_DEV_FN_OTG))
81 		return -EINVAL;
82 
83 	func = cdns3_get_second_fun(pdev);
84 	if (unlikely(!func))
85 		return -EINVAL;
86 
87 	err = pcim_enable_device(pdev);
88 	if (err) {
89 		dev_err(&pdev->dev, "Enabling PCI device has failed %d\n", err);
90 		return err;
91 	}
92 
93 	pci_set_master(pdev);
94 
95 	if (pci_is_enabled(func)) {
96 		wrap = pci_get_drvdata(func);
97 	} else {
98 		wrap = kzalloc(sizeof(*wrap), GFP_KERNEL);
99 		if (!wrap) {
100 			pci_disable_device(pdev);
101 			return -ENOMEM;
102 		}
103 	}
104 
105 	res = wrap->dev_res;
106 
107 	if (pdev->devfn == PCI_DEV_FN_HOST_DEVICE) {
108 		/* function 0: host(BAR_0) + device(BAR_1).*/
109 		dev_dbg(&pdev->dev, "Initialize Device resources\n");
110 		res[RES_DEV_ID].start = pci_resource_start(pdev, PCI_BAR_DEV);
111 		res[RES_DEV_ID].end =   pci_resource_end(pdev, PCI_BAR_DEV);
112 		res[RES_DEV_ID].name = "dev";
113 		res[RES_DEV_ID].flags = IORESOURCE_MEM;
114 		dev_dbg(&pdev->dev, "USBSS-DEV physical base addr: %pa\n",
115 			&res[RES_DEV_ID].start);
116 
117 		res[RES_HOST_ID].start = pci_resource_start(pdev, PCI_BAR_HOST);
118 		res[RES_HOST_ID].end = pci_resource_end(pdev, PCI_BAR_HOST);
119 		res[RES_HOST_ID].name = "xhci";
120 		res[RES_HOST_ID].flags = IORESOURCE_MEM;
121 		dev_dbg(&pdev->dev, "USBSS-XHCI physical base addr: %pa\n",
122 			&res[RES_HOST_ID].start);
123 
124 		/* Interrupt for XHCI */
125 		wrap->dev_res[RES_IRQ_HOST_ID].start = pdev->irq;
126 		wrap->dev_res[RES_IRQ_HOST_ID].name = "host";
127 		wrap->dev_res[RES_IRQ_HOST_ID].flags = IORESOURCE_IRQ;
128 
129 		/* Interrupt device. It's the same as for HOST. */
130 		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].start = pdev->irq;
131 		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].name = "peripheral";
132 		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].flags = IORESOURCE_IRQ;
133 	} else {
134 		res[RES_DRD_ID].start = pci_resource_start(pdev, PCI_BAR_OTG);
135 		res[RES_DRD_ID].end =   pci_resource_end(pdev, PCI_BAR_OTG);
136 		res[RES_DRD_ID].name = "otg";
137 		res[RES_DRD_ID].flags = IORESOURCE_MEM;
138 		dev_dbg(&pdev->dev, "USBSS-DRD physical base addr: %pa\n",
139 			&res[RES_DRD_ID].start);
140 
141 		/* Interrupt for OTG/DRD. */
142 		wrap->dev_res[RES_IRQ_OTG_ID].start = pdev->irq;
143 		wrap->dev_res[RES_IRQ_OTG_ID].name = "otg";
144 		wrap->dev_res[RES_IRQ_OTG_ID].flags = IORESOURCE_IRQ;
145 	}
146 
147 	if (pci_is_enabled(func)) {
148 		/* set up platform device info */
149 		memset(&plat_info, 0, sizeof(plat_info));
150 		plat_info.parent = &pdev->dev;
151 		plat_info.fwnode = pdev->dev.fwnode;
152 		plat_info.name = PLAT_DRIVER_NAME;
153 		plat_info.id = pdev->devfn;
154 		wrap->devfn  = pdev->devfn;
155 		plat_info.res = wrap->dev_res;
156 		plat_info.num_res = ARRAY_SIZE(wrap->dev_res);
157 		plat_info.dma_mask = pdev->dma_mask;
158 		/* register platform device */
159 		wrap->plat_dev = platform_device_register_full(&plat_info);
160 		if (IS_ERR(wrap->plat_dev)) {
161 			pci_disable_device(pdev);
162 			err = PTR_ERR(wrap->plat_dev);
163 			kfree(wrap);
164 			return err;
165 		}
166 	}
167 
168 	pci_set_drvdata(pdev, wrap);
169 	return err;
170 }
171 
cdns3_pci_remove(struct pci_dev * pdev)172 static void cdns3_pci_remove(struct pci_dev *pdev)
173 {
174 	struct cdns3_wrap *wrap;
175 	struct pci_dev *func;
176 
177 	func = cdns3_get_second_fun(pdev);
178 
179 	wrap = (struct cdns3_wrap *)pci_get_drvdata(pdev);
180 	if (wrap->devfn == pdev->devfn)
181 		platform_device_unregister(wrap->plat_dev);
182 
183 	if (!pci_is_enabled(func))
184 		kfree(wrap);
185 }
186 
187 static const struct pci_device_id cdns3_pci_ids[] = {
188 	{ PCI_DEVICE(CDNS_VENDOR_ID, CDNS_DEVICE_ID), },
189 	{ 0, }
190 };
191 
192 static struct pci_driver cdns3_pci_driver = {
193 	.name = PCI_DRIVER_NAME,
194 	.id_table = cdns3_pci_ids,
195 	.probe = cdns3_pci_probe,
196 	.remove = cdns3_pci_remove,
197 };
198 
199 module_pci_driver(cdns3_pci_driver);
200 MODULE_DEVICE_TABLE(pci, cdns3_pci_ids);
201 
202 MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
203 MODULE_LICENSE("GPL v2");
204 MODULE_DESCRIPTION("Cadence USBSS PCI wrapper");
205