1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright (C) 2007 by Alan Stern
6 /* this file is part of ehci-hcd.c */
9 /* Display the ports dedicated to the companion controller */
10 static ssize_t companion_show(struct device *dev,
11 struct device_attribute *attr,
14 struct ehci_hcd *ehci;
16 int count = PAGE_SIZE;
19 ehci = hcd_to_ehci(dev_get_drvdata(dev));
20 nports = HCS_N_PORTS(ehci->hcs_params);
22 for (index = 0; index < nports; ++index) {
23 if (test_bit(index, &ehci->companion_ports)) {
24 n = scnprintf(ptr, count, "%d\n", index + 1);
33 * Dedicate or undedicate a port to the companion controller.
34 * Syntax is "[-]portnum", where a leading '-' sign means
35 * return control of the port to the EHCI controller.
37 static ssize_t companion_store(struct device *dev,
38 struct device_attribute *attr,
39 const char *buf, size_t count)
41 struct ehci_hcd *ehci;
42 int portnum, new_owner;
44 ehci = hcd_to_ehci(dev_get_drvdata(dev));
45 new_owner = PORT_OWNER; /* Owned by companion */
46 if (sscanf(buf, "%d", &portnum) != 1)
50 new_owner = 0; /* Owned by EHCI */
52 if (portnum <= 0 || portnum > HCS_N_PORTS(ehci->hcs_params))
56 set_bit(portnum, &ehci->companion_ports);
58 clear_bit(portnum, &ehci->companion_ports);
59 set_owner(ehci, portnum, new_owner);
62 static DEVICE_ATTR_RW(companion);
66 * Display / Set uframe_periodic_max
68 static ssize_t uframe_periodic_max_show(struct device *dev,
69 struct device_attribute *attr,
72 struct ehci_hcd *ehci;
75 ehci = hcd_to_ehci(dev_get_drvdata(dev));
76 n = scnprintf(buf, PAGE_SIZE, "%d\n", ehci->uframe_periodic_max);
81 static ssize_t uframe_periodic_max_store(struct device *dev,
82 struct device_attribute *attr,
83 const char *buf, size_t count)
85 struct ehci_hcd *ehci;
86 unsigned uframe_periodic_max;
91 ehci = hcd_to_ehci(dev_get_drvdata(dev));
92 if (kstrtouint(buf, 0, &uframe_periodic_max) < 0)
95 if (uframe_periodic_max < 100 || uframe_periodic_max >= 125) {
96 ehci_info(ehci, "rejecting invalid request for "
97 "uframe_periodic_max=%u\n", uframe_periodic_max);
104 * lock, so that our checking does not race with possible periodic
105 * bandwidth allocation through submitting new urbs.
107 spin_lock_irqsave (&ehci->lock, flags);
110 * for request to decrease max periodic bandwidth, we have to check
111 * to see whether the decrease is possible.
113 if (uframe_periodic_max < ehci->uframe_periodic_max) {
114 u8 allocated_max = 0;
116 for (uframe = 0; uframe < EHCI_BANDWIDTH_SIZE; ++uframe)
117 allocated_max = max(allocated_max,
118 ehci->bandwidth[uframe]);
120 if (allocated_max > uframe_periodic_max) {
122 "cannot decrease uframe_periodic_max because "
123 "periodic bandwidth is already allocated "
125 allocated_max, uframe_periodic_max);
130 /* increasing is always ok */
132 ehci_info(ehci, "setting max periodic bandwidth to %u%% "
133 "(== %u usec/uframe)\n",
134 100*uframe_periodic_max/125, uframe_periodic_max);
136 if (uframe_periodic_max != 100)
137 ehci_warn(ehci, "max periodic bandwidth set is non-standard\n");
139 ehci->uframe_periodic_max = uframe_periodic_max;
143 spin_unlock_irqrestore (&ehci->lock, flags);
146 static DEVICE_ATTR_RW(uframe_periodic_max);
149 static inline int create_sysfs_files(struct ehci_hcd *ehci)
151 struct device *controller = ehci_to_hcd(ehci)->self.controller;
154 /* with integrated TT there is no companion! */
155 if (!ehci_is_TDI(ehci))
156 i = device_create_file(controller, &dev_attr_companion);
160 i = device_create_file(controller, &dev_attr_uframe_periodic_max);
165 static inline void remove_sysfs_files(struct ehci_hcd *ehci)
167 struct device *controller = ehci_to_hcd(ehci)->self.controller;
169 /* with integrated TT there is no companion! */
170 if (!ehci_is_TDI(ehci))
171 device_remove_file(controller, &dev_attr_companion);
173 device_remove_file(controller, &dev_attr_uframe_periodic_max);