1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Generic UHCI HCD (Host Controller Driver) for Platform Devices
  4 *
  5 * Copyright (c) 2011 Tony Prisk <linux@prisktech.co.nz>
  6 *
  7 * This file is based on uhci-grlib.c
  8 * (C) Copyright 2004-2007 Alan Stern, stern@rowland.harvard.edu
  9 */
 10
 11#include <linux/of.h>
 12#include <linux/device.h>
 13#include <linux/platform_device.h>
 14
 15static int uhci_platform_init(struct usb_hcd *hcd)
 16{
 17	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
 18
 19	/* Probe number of ports if not already provided by DT */
 20	if (!uhci->rh_numports)
 21		uhci->rh_numports = uhci_count_ports(hcd);
 22
 23	/* Set up pointers to to generic functions */
 24	uhci->reset_hc = uhci_generic_reset_hc;
 25	uhci->check_and_reset_hc = uhci_generic_check_and_reset_hc;
 26
 27	/* No special actions need to be taken for the functions below */
 28	uhci->configure_hc = NULL;
 29	uhci->resume_detect_interrupts_are_broken = NULL;
 30	uhci->global_suspend_mode_is_broken = NULL;
 31
 32	/* Reset if the controller isn't already safely quiescent. */
 33	check_and_reset_hc(uhci);
 34	return 0;
 35}
 36
 37static const struct hc_driver uhci_platform_hc_driver = {
 38	.description =		hcd_name,
 39	.product_desc =		"Generic UHCI Host Controller",
 40	.hcd_priv_size =	sizeof(struct uhci_hcd),
 41
 42	/* Generic hardware linkage */
 43	.irq =			uhci_irq,
 44	.flags =		HCD_MEMORY | HCD_DMA | HCD_USB11,
 45
 46	/* Basic lifecycle operations */
 47	.reset =		uhci_platform_init,
 48	.start =		uhci_start,
 49#ifdef CONFIG_PM
 50	.pci_suspend =		NULL,
 51	.pci_resume =		NULL,
 52	.bus_suspend =		uhci_rh_suspend,
 53	.bus_resume =		uhci_rh_resume,
 54#endif
 55	.stop =			uhci_stop,
 56
 57	.urb_enqueue =		uhci_urb_enqueue,
 58	.urb_dequeue =		uhci_urb_dequeue,
 59
 60	.endpoint_disable =	uhci_hcd_endpoint_disable,
 61	.get_frame_number =	uhci_hcd_get_frame_number,
 62
 63	.hub_status_data =	uhci_hub_status_data,
 64	.hub_control =		uhci_hub_control,
 65};
 66
 67static int uhci_hcd_platform_probe(struct platform_device *pdev)
 68{
 69	struct device_node *np = pdev->dev.of_node;
 70	struct usb_hcd *hcd;
 71	struct uhci_hcd	*uhci;
 72	struct resource *res;
 73	int ret;
 74
 75	if (usb_disabled())
 76		return -ENODEV;
 77
 78	/*
 79	 * Right now device-tree probed devices don't get dma_mask set.
 80	 * Since shared usb code relies on it, set it here for now.
 81	 * Once we have dma capability bindings this can go away.
 82	 */
 83	ret = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
 84	if (ret)
 85		return ret;
 86
 87	hcd = usb_create_hcd(&uhci_platform_hc_driver, &pdev->dev,
 88			pdev->name);
 89	if (!hcd)
 90		return -ENOMEM;
 91
 92	uhci = hcd_to_uhci(hcd);
 93
 94	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 95	hcd->regs = devm_ioremap_resource(&pdev->dev, res);
 96	if (IS_ERR(hcd->regs)) {
 97		ret = PTR_ERR(hcd->regs);
 98		goto err_rmr;
 99	}
100	hcd->rsrc_start = res->start;
101	hcd->rsrc_len = resource_size(res);
102
103	uhci->regs = hcd->regs;
104
105	/* Grab some things from the device-tree */
106	if (np) {
107		u32 num_ports;
108
109		if (of_property_read_u32(np, "#ports", &num_ports) == 0) {
110			uhci->rh_numports = num_ports;
111			dev_info(&pdev->dev,
112				"Detected %d ports from device-tree\n",
113				num_ports);
114		}
115		if (of_device_is_compatible(np, "aspeed,ast2400-uhci") ||
116		    of_device_is_compatible(np, "aspeed,ast2500-uhci") ||
117		    of_device_is_compatible(np, "aspeed,ast2600-uhci")) {
118			uhci->is_aspeed = 1;
119			dev_info(&pdev->dev,
120				 "Enabled Aspeed implementation workarounds\n");
121		}
122	}
123
124	/* Get and enable clock if any specified */
125	uhci->clk = devm_clk_get(&pdev->dev, NULL);
126	if (IS_ERR(uhci->clk)) {
127		ret = PTR_ERR(uhci->clk);
128		goto err_rmr;
129	}
130	ret = clk_prepare_enable(uhci->clk);
131	if (ret) {
132		dev_err(&pdev->dev, "Error couldn't enable clock (%d)\n", ret);
133		goto err_rmr;
134	}
135
136	ret = platform_get_irq(pdev, 0);
137	if (ret < 0)
138		goto err_clk;
139
140	ret = usb_add_hcd(hcd, ret, IRQF_SHARED);
141	if (ret)
142		goto err_clk;
143
144	device_wakeup_enable(hcd->self.controller);
145	return 0;
146
147err_clk:
148	clk_disable_unprepare(uhci->clk);
149err_rmr:
150	usb_put_hcd(hcd);
151
152	return ret;
153}
154
155static int uhci_hcd_platform_remove(struct platform_device *pdev)
156{
157	struct usb_hcd *hcd = platform_get_drvdata(pdev);
158	struct uhci_hcd *uhci = hcd_to_uhci(hcd);
159
160	clk_disable_unprepare(uhci->clk);
161	usb_remove_hcd(hcd);
162	usb_put_hcd(hcd);
163
164	return 0;
165}
166
167/* Make sure the controller is quiescent and that we're not using it
168 * any more.  This is mainly for the benefit of programs which, like kexec,
169 * expect the hardware to be idle: not doing DMA or generating IRQs.
170 *
171 * This routine may be called in a damaged or failing kernel.  Hence we
172 * do not acquire the spinlock before shutting down the controller.
173 */
174static void uhci_hcd_platform_shutdown(struct platform_device *op)
175{
176	struct usb_hcd *hcd = platform_get_drvdata(op);
177
178	uhci_hc_died(hcd_to_uhci(hcd));
179}
180
181static const struct of_device_id platform_uhci_ids[] = {
182	{ .compatible = "generic-uhci", },
183	{ .compatible = "platform-uhci", },
184	{}
185};
186MODULE_DEVICE_TABLE(of, platform_uhci_ids);
187
188static struct platform_driver uhci_platform_driver = {
189	.probe		= uhci_hcd_platform_probe,
190	.remove		= uhci_hcd_platform_remove,
191	.shutdown	= uhci_hcd_platform_shutdown,
192	.driver = {
193		.name = "platform-uhci",
194		.of_match_table = platform_uhci_ids,
195	},
196};