summaryrefslogtreecommitdiffstats
path: root/drivers/usb/host/ehci-sysfs.c
blob: 8f75cb7b197cbaee0567772a22681bc2c4b6a8aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright (C) 2007 by Alan Stern
 */

/* this file is part of ehci-hcd.c */


/* Display the ports dedicated to the companion controller */
static ssize_t companion_show(struct device *dev,
			      struct device_attribute *attr,
			      char *buf)
{
	struct ehci_hcd		*ehci;
	int			nports, index, n;
	int			count = PAGE_SIZE;
	char			*ptr = buf;

	ehci = hcd_to_ehci(dev_get_drvdata(dev));
	nports = HCS_N_PORTS(ehci->hcs_params);

	for (index = 0; index < nports; ++index) {
		if (test_bit(index, &ehci->companion_ports)) {
			n = scnprintf(ptr, count, "%d\n", index + 1);
			ptr += n;
			count -= n;
		}
	}
	return ptr - buf;
}

/*
 * Dedicate or undedicate a port to the companion controller.
 * Syntax is "[-]portnum", where a leading '-' sign means
 * return control of the port to the EHCI controller.
 */
static ssize_t companion_store(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t count)
{
	struct ehci_hcd		*ehci;
	int			portnum, new_owner;

	ehci = hcd_to_ehci(dev_get_drvdata(dev));
	new_owner = PORT_OWNER;		/* Owned by companion */
	if (sscanf(buf, "%d", &portnum) != 1)
		return -EINVAL;
	if (portnum < 0) {
		portnum = - portnum;
		new_owner = 0;		/* Owned by EHCI */
	}
	if (portnum <= 0 || portnum > HCS_N_PORTS(ehci->hcs_params))
		return -ENOENT;
	portnum--;
	if (new_owner)
		set_bit(portnum, &ehci->companion_ports);
	else
		clear_bit(portnum, &ehci->companion_ports);
	set_owner(ehci, portnum, new_owner);
	return count;
}
static DEVICE_ATTR_RW(companion);


/*
 * Display / Set uframe_periodic_max
 */
static ssize_t uframe_periodic_max_show(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct ehci_hcd		*ehci;
	int			n;

	ehci = hcd_to_ehci(dev_get_drvdata(dev));
	n = scnprintf(buf, PAGE_SIZE, "%d\n", ehci->uframe_periodic_max);
	return n;
}


static ssize_t uframe_periodic_max_store(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t count)
{
	struct ehci_hcd		*ehci;
	unsigned		uframe_periodic_max;
	unsigned		uframe;
	unsigned long		flags;
	ssize_t			ret;

	ehci = hcd_to_ehci(dev_get_drvdata(dev));
	if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
		return -EINVAL;

	if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) {
		ehci_info(ehci, "rejecting invalid request for "
				"uframe_periodic_max=%u\n", uframe_periodic_max);
		return -EINVAL;
	}

	ret = -EINVAL;

	/*
	 * lock, so that our checking does not race with possible periodic
	 * bandwidth allocation through submitting new urbs.
	 */
	spin_lock_irqsave (&ehci->lock, flags);

	/*
	 * for request to decrease max periodic bandwidth, we have to check
	 * to see whether the decrease is possible.
	 */
	if (uframe_periodic_max < ehci->uframe_periodic_max) {
		u8		allocated_max = 0;

		for (uframe = 0; uframe < EHCI_BANDWIDTH_SIZE; ++uframe)
			allocated_max = max(allocated_max,
					ehci->bandwidth[uframe]);

		if (allocated_max > uframe_periodic_max) {
			ehci_info(ehci,
				"cannot decrease uframe_periodic_max because "
				"periodic bandwidth is already allocated "
				"(%u > %u)\n",
				allocated_max, uframe_periodic_max);
			goto out_unlock;
		}
	}

	/* increasing is always ok */

	ehci_info(ehci, "setting max periodic bandwidth to %u%% "
			"(== %u usec/uframe)\n",
			100*uframe_periodic_max/125, uframe_periodic_max);

	if (uframe_periodic_max != 100)
		ehci_warn(ehci, "max periodic bandwidth set is non-standard\n");

	ehci->uframe_periodic_max = uframe_periodic_max;
	ret = count;

out_unlock:
	spin_unlock_irqrestore (&ehci->lock, flags);
	return ret;
}
static DEVICE_ATTR_RW(uframe_periodic_max);


static inline int create_sysfs_files(struct ehci_hcd *ehci)
{
	struct device	*controller = ehci_to_hcd(ehci)->self.controller;
	int	i = 0;

	/* with integrated TT there is no companion! */
	if (!ehci_is_TDI(ehci))
		i = device_create_file(controller, &dev_attr_companion);
	if (i)
		goto out;

	i = device_create_file(controller, &dev_attr_uframe_periodic_max);
out:
	return i;
}

static inline void remove_sysfs_files(struct ehci_hcd *ehci)
{
	struct device	*controller = ehci_to_hcd(ehci)->self.controller;

	/* with integrated TT there is no companion! */
	if (!ehci_is_TDI(ehci))
		device_remove_file(controller, &dev_attr_companion);

	device_remove_file(controller, &dev_attr_uframe_periodic_max);
}