diff options
Diffstat (limited to 'drivers/usb/host/ehci-sysfs.c')
| -rw-r--r-- | drivers/usb/host/ehci-sysfs.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-sysfs.c b/drivers/usb/host/ehci-sysfs.c new file mode 100644 index 0000000000..8f75cb7b19 --- /dev/null +++ b/drivers/usb/host/ehci-sysfs.c @@ -0,0 +1,174 @@ +// 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); +} |