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
17struct 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
43static 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	if (func->devfn != PCI_DEV_FN_HOST_DEVICE &&
64	    func->devfn != PCI_DEV_FN_OTG) {
65		return NULL;
66	}
67
68	return func;
69}
70
71static int cdns3_pci_probe(struct pci_dev *pdev,
72			   const struct pci_device_id *id)
73{
74	struct platform_device_info plat_info;
75	struct cdns3_wrap *wrap;
76	struct resource *res;
77	struct pci_dev *func;
78	int err;
79
80	/*
81	 * for GADGET/HOST PCI (devfn) function number is 0,
82	 * for OTG PCI (devfn) function number is 1
83	 */
84	if (!id || (pdev->devfn != PCI_DEV_FN_HOST_DEVICE &&
85		    pdev->devfn != PCI_DEV_FN_OTG))
86		return -EINVAL;
87
88	func = cdns3_get_second_fun(pdev);
89	if (unlikely(!func))
90		return -EINVAL;
91
92	err = pcim_enable_device(pdev);
93	if (err) {
94		dev_err(&pdev->dev, "Enabling PCI device has failed %d\n", err);
95		return err;
96	}
97
98	pci_set_master(pdev);
99
100	if (pci_is_enabled(func)) {
101		wrap = pci_get_drvdata(func);
102	} else {
103		wrap = kzalloc(sizeof(*wrap), GFP_KERNEL);
104		if (!wrap) {
105			pci_disable_device(pdev);
106			return -ENOMEM;
107		}
108	}
109
110	res = wrap->dev_res;
111
112	if (pdev->devfn == PCI_DEV_FN_HOST_DEVICE) {
113		/* function 0: host(BAR_0) + device(BAR_1).*/
114		dev_dbg(&pdev->dev, "Initialize Device resources\n");
115		res[RES_DEV_ID].start = pci_resource_start(pdev, PCI_BAR_DEV);
116		res[RES_DEV_ID].end =   pci_resource_end(pdev, PCI_BAR_DEV);
117		res[RES_DEV_ID].name = "dev";
118		res[RES_DEV_ID].flags = IORESOURCE_MEM;
119		dev_dbg(&pdev->dev, "USBSS-DEV physical base addr: %pa\n",
120			&res[RES_DEV_ID].start);
121
122		res[RES_HOST_ID].start = pci_resource_start(pdev, PCI_BAR_HOST);
123		res[RES_HOST_ID].end = pci_resource_end(pdev, PCI_BAR_HOST);
124		res[RES_HOST_ID].name = "xhci";
125		res[RES_HOST_ID].flags = IORESOURCE_MEM;
126		dev_dbg(&pdev->dev, "USBSS-XHCI physical base addr: %pa\n",
127			&res[RES_HOST_ID].start);
128
129		/* Interrupt for XHCI */
130		wrap->dev_res[RES_IRQ_HOST_ID].start = pdev->irq;
131		wrap->dev_res[RES_IRQ_HOST_ID].name = "host";
132		wrap->dev_res[RES_IRQ_HOST_ID].flags = IORESOURCE_IRQ;
133
134		/* Interrupt device. It's the same as for HOST. */
135		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].start = pdev->irq;
136		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].name = "peripheral";
137		wrap->dev_res[RES_IRQ_PERIPHERAL_ID].flags = IORESOURCE_IRQ;
138	} else {
139		res[RES_DRD_ID].start = pci_resource_start(pdev, PCI_BAR_OTG);
140		res[RES_DRD_ID].end =   pci_resource_end(pdev, PCI_BAR_OTG);
141		res[RES_DRD_ID].name = "otg";
142		res[RES_DRD_ID].flags = IORESOURCE_MEM;
143		dev_dbg(&pdev->dev, "USBSS-DRD physical base addr: %pa\n",
144			&res[RES_DRD_ID].start);
145
146		/* Interrupt for OTG/DRD. */
147		wrap->dev_res[RES_IRQ_OTG_ID].start = pdev->irq;
148		wrap->dev_res[RES_IRQ_OTG_ID].name = "otg";
149		wrap->dev_res[RES_IRQ_OTG_ID].flags = IORESOURCE_IRQ;
150	}
151
152	if (pci_is_enabled(func)) {
153		/* set up platform device info */
154		memset(&plat_info, 0, sizeof(plat_info));
155		plat_info.parent = &pdev->dev;
156		plat_info.fwnode = pdev->dev.fwnode;
157		plat_info.name = PLAT_DRIVER_NAME;
158		plat_info.id = pdev->devfn;
159		wrap->devfn  = pdev->devfn;
160		plat_info.res = wrap->dev_res;
161		plat_info.num_res = ARRAY_SIZE(wrap->dev_res);
162		plat_info.dma_mask = pdev->dma_mask;
163		/* register platform device */
164		wrap->plat_dev = platform_device_register_full(&plat_info);
165		if (IS_ERR(wrap->plat_dev)) {
166			pci_disable_device(pdev);
167			err = PTR_ERR(wrap->plat_dev);
168			kfree(wrap);
169			return err;
170		}
171	}
172
173	pci_set_drvdata(pdev, wrap);
174	return err;
175}
176
177static void cdns3_pci_remove(struct pci_dev *pdev)
178{
179	struct cdns3_wrap *wrap;
180	struct pci_dev *func;
181
182	func = cdns3_get_second_fun(pdev);
183
184	wrap = (struct cdns3_wrap *)pci_get_drvdata(pdev);
185	if (wrap->devfn == pdev->devfn)
186		platform_device_unregister(wrap->plat_dev);
187
188	if (!pci_is_enabled(func))
189		kfree(wrap);
190}
191
192static const struct pci_device_id cdns3_pci_ids[] = {
193	{ PCI_DEVICE(CDNS_VENDOR_ID, CDNS_DEVICE_ID), },
194	{ 0, }
195};
196
197static struct pci_driver cdns3_pci_driver = {
198	.name = PCI_DRIVER_NAME,
199	.id_table = cdns3_pci_ids,
200	.probe = cdns3_pci_probe,
201	.remove = cdns3_pci_remove,
202};
203
204module_pci_driver(cdns3_pci_driver);
205MODULE_DEVICE_TABLE(pci, cdns3_pci_ids);
206
207MODULE_AUTHOR("Pawel Laszczak <pawell@cadence.com>");
208MODULE_LICENSE("GPL v2");
209MODULE_DESCRIPTION("Cadence USBSS PCI wrapper");
210