#include <asm/unaligned.h>
#include <linux/platform_device.h>
#include <linux/workqueue.h>
+#include <linux/mutex.h>
#include <linux/usb.h>
}
}
-/* Check whether a new configuration or alt setting for an interface
- * will exceed the bandwidth for the bus (or the host controller resources).
- * Only pass in a non-NULL config or interface, not both!
- * Passing NULL for both new_config and new_intf means the device will be
- * de-configured by issuing a set configuration 0 command.
+/**
+ * Check whether a new bandwidth setting exceeds the bus bandwidth.
+ * @new_config: new configuration to install
+ * @cur_alt: the current alternate interface setting
+ * @new_alt: alternate interface setting that is being installed
+ *
+ * To change configurations, pass in the new configuration in new_config,
+ * and pass NULL for cur_alt and new_alt.
+ *
+ * To reset a device's configuration (put the device in the ADDRESSED state),
+ * pass in NULL for new_config, cur_alt, and new_alt.
+ *
+ * To change alternate interface settings, pass in NULL for new_config,
+ * pass in the current alternate interface setting in cur_alt,
+ * and pass in the new alternate interface setting in new_alt.
+ *
+ * Returns an error if the requested bandwidth change exceeds the
+ * bus bandwidth or host controller internal resources.
*/
-int usb_hcd_check_bandwidth(struct usb_device *udev,
+int usb_hcd_alloc_bandwidth(struct usb_device *udev,
struct usb_host_config *new_config,
- struct usb_interface *new_intf)
+ struct usb_host_interface *cur_alt,
+ struct usb_host_interface *new_alt)
{
int num_intfs, i, j;
struct usb_host_interface *alt = NULL;
return 0;
/* Configuration is being removed - set configuration 0 */
- if (!new_config && !new_intf) {
+ if (!new_config && !cur_alt) {
for (i = 1; i < 16; ++i) {
ep = udev->ep_out[i];
if (ep)
for (i = 0; i < num_intfs; ++i) {
/* Set up endpoints for alternate interface setting 0 */
alt = usb_find_alt_setting(new_config, i, 0);
- if (!alt) {
- printk(KERN_DEBUG "Did not find alt setting 0 for intf %d\n", i);
- continue;
- }
+ if (!alt)
+ /* No alt setting 0? Pick the first setting. */
+ alt = &new_config->intf_cache[i]->altsetting[0];
+
for (j = 0; j < alt->desc.bNumEndpoints; j++) {
ret = hcd->driver->add_endpoint(hcd, udev, &alt->endpoint[j]);
if (ret < 0)
}
}
}
+ if (cur_alt && new_alt) {
+ /* Drop all the endpoints in the current alt setting */
+ for (i = 0; i < cur_alt->desc.bNumEndpoints; i++) {
+ ret = hcd->driver->drop_endpoint(hcd, udev,
+ &cur_alt->endpoint[i]);
+ if (ret < 0)
+ goto reset;
+ }
+ /* Add all the endpoints in the new alt setting */
+ for (i = 0; i < new_alt->desc.bNumEndpoints; i++) {
+ ret = hcd->driver->add_endpoint(hcd, udev,
+ &new_alt->endpoint[i]);
+ if (ret < 0)
+ goto reset;
+ }
+ }
ret = hcd->driver->check_bandwidth(hcd, udev);
reset:
if (ret < 0)
#ifdef CONFIG_PM
INIT_WORK(&hcd->wakeup_work, hcd_resume_work);
#endif
+ mutex_init(&hcd->bandwidth_mutex);
hcd->driver = driver;
hcd->product_desc = (driver->product_desc) ? driver->product_desc :
u64 rsrc_len; /* memory/io resource length */
unsigned power_budget; /* in mA, 0 = no limit */
+ /* bandwidth_mutex should be taken before adding or removing
+ * any new bus bandwidth constraints:
+ * 1. Before adding a configuration for a new device.
+ * 2. Before removing the configuration to put the device into
+ * the addressed state.
+ * 3. Before selecting a different configuration.
+ * 4. Before selecting an alternate interface setting.
+ *
+ * bandwidth_mutex should be dropped after a successful control message
+ * to the device, or resetting the bandwidth after a failed attempt.
+ */
+ struct mutex bandwidth_mutex;
+
+
#define HCD_BUFFER_POOLS 4
struct dma_pool *pool [HCD_BUFFER_POOLS];
extern void usb_hcd_reset_endpoint(struct usb_device *udev,
struct usb_host_endpoint *ep);
extern void usb_hcd_synchronize_unlinks(struct usb_device *udev);
-extern int usb_hcd_check_bandwidth(struct usb_device *udev,
+extern int usb_hcd_alloc_bandwidth(struct usb_device *udev,
struct usb_host_config *new_config,
- struct usb_interface *new_intf);
+ struct usb_host_interface *old_alt,
+ struct usb_host_interface *new_alt);
extern int usb_hcd_get_frame_number(struct usb_device *udev);
extern struct usb_hcd *usb_create_hcd(const struct hc_driver *driver,
{
struct usb_device *parent_hdev = udev->parent;
struct usb_hub *parent_hub;
+ struct usb_hcd *hcd = bus_to_hcd(udev->bus);
struct usb_device_descriptor descriptor = udev->descriptor;
int i, ret = 0;
int port1 = udev->portnum;
/* Restore the device's previous configuration */
if (!udev->actconfig)
goto done;
+
+ mutex_lock(&hcd->bandwidth_mutex);
+ ret = usb_hcd_alloc_bandwidth(udev, udev->actconfig, NULL, NULL);
+ if (ret < 0) {
+ dev_warn(&udev->dev,
+ "Busted HC? Not enough HCD resources for "
+ "old configuration.\n");
+ mutex_unlock(&hcd->bandwidth_mutex);
+ goto re_enumerate;
+ }
ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
USB_REQ_SET_CONFIGURATION, 0,
udev->actconfig->desc.bConfigurationValue, 0,
dev_err(&udev->dev,
"can't restore configuration #%d (error=%d)\n",
udev->actconfig->desc.bConfigurationValue, ret);
+ mutex_unlock(&hcd->bandwidth_mutex);
goto re_enumerate;
}
+ mutex_unlock(&hcd->bandwidth_mutex);
usb_set_device_state(udev, USB_STATE_CONFIGURED);
/* Put interfaces back into the same altsettings as before.
* endpoint state.
*/
for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
- struct usb_interface *intf = udev->actconfig->interface[i];
+ struct usb_host_config *config = udev->actconfig;
+ struct usb_interface *intf = config->interface[i];
struct usb_interface_descriptor *desc;
desc = &intf->cur_altsetting->desc;
usb_enable_interface(udev, intf, true);
ret = 0;
} else {
+ /* We've just reset the device, so it will think alt
+ * setting 0 is installed. For usb_set_interface() to
+ * work properly, we need to set the current alternate
+ * interface setting to 0 (or the first alt setting, if
+ * the device doesn't have alt setting 0).
+ */
+ intf->cur_altsetting =
+ usb_find_alt_setting(config, i, 0);
+ if (!intf->cur_altsetting)
+ intf->cur_altsetting =
+ &config->intf_cache[i]->altsetting[0];
ret = usb_set_interface(udev, desc->bInterfaceNumber,
desc->bAlternateSetting);
}
{
struct usb_interface *iface;
struct usb_host_interface *alt;
+ struct usb_hcd *hcd = bus_to_hcd(dev->bus);
int ret;
int manual = 0;
unsigned int epaddr;
return -EINVAL;
}
+ /* Make sure we have enough bandwidth for this alternate interface.
+ * Remove the current alt setting and add the new alt setting.
+ */
+ mutex_lock(&hcd->bandwidth_mutex);
+ ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt);
+ if (ret < 0) {
+ dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n",
+ alternate);
+ mutex_unlock(&hcd->bandwidth_mutex);
+ return ret;
+ }
+
if (dev->quirks & USB_QUIRK_NO_SET_INTF)
ret = -EPIPE;
else
"manual set_interface for iface %d, alt %d\n",
interface, alternate);
manual = 1;
- } else if (ret < 0)
+ } else if (ret < 0) {
+ /* Re-instate the old alt setting */
+ usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting);
+ mutex_unlock(&hcd->bandwidth_mutex);
return ret;
+ }
+ mutex_unlock(&hcd->bandwidth_mutex);
/* FIXME drivers shouldn't need to replicate/bugfix the logic here
* when they implement async or easily-killable versions of this or
{
int i, retval;
struct usb_host_config *config;
+ struct usb_hcd *hcd = bus_to_hcd(dev->bus);
if (dev->state == USB_STATE_SUSPENDED)
return -EHOSTUNREACH;
}
config = dev->actconfig;
+ retval = 0;
+ mutex_lock(&hcd->bandwidth_mutex);
+ /* Make sure we have enough bandwidth for each alternate setting 0 */
+ for (i = 0; i < config->desc.bNumInterfaces; i++) {
+ struct usb_interface *intf = config->interface[i];
+ struct usb_host_interface *alt;
+
+ alt = usb_altnum_to_altsetting(intf, 0);
+ if (!alt)
+ alt = &intf->altsetting[0];
+ if (alt != intf->cur_altsetting)
+ retval = usb_hcd_alloc_bandwidth(dev, NULL,
+ intf->cur_altsetting, alt);
+ if (retval < 0)
+ break;
+ }
+ /* If not, reinstate the old alternate settings */
+ if (retval < 0) {
+reset_old_alts:
+ for (; i >= 0; i--) {
+ struct usb_interface *intf = config->interface[i];
+ struct usb_host_interface *alt;
+
+ alt = usb_altnum_to_altsetting(intf, 0);
+ if (!alt)
+ alt = &intf->altsetting[0];
+ if (alt != intf->cur_altsetting)
+ usb_hcd_alloc_bandwidth(dev, NULL,
+ alt, intf->cur_altsetting);
+ }
+ mutex_unlock(&hcd->bandwidth_mutex);
+ return retval;
+ }
retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
USB_REQ_SET_CONFIGURATION, 0,
config->desc.bConfigurationValue, 0,
NULL, 0, USB_CTRL_SET_TIMEOUT);
if (retval < 0)
- return retval;
+ goto reset_old_alts;
+ mutex_unlock(&hcd->bandwidth_mutex);
/* re-init hc/hcd interface/endpoint state */
for (i = 0; i < config->desc.bNumInterfaces; i++) {
int i, ret;
struct usb_host_config *cp = NULL;
struct usb_interface **new_interfaces = NULL;
+ struct usb_hcd *hcd = bus_to_hcd(dev->bus);
int n, nintf;
if (dev->authorized == 0 || configuration == -1)
* host controller will not allow submissions to dropped endpoints. If
* this call fails, the device state is unchanged.
*/
- if (cp)
- ret = usb_hcd_check_bandwidth(dev, cp, NULL);
- else
- ret = usb_hcd_check_bandwidth(dev, NULL, NULL);
+ mutex_lock(&hcd->bandwidth_mutex);
+ ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL);
if (ret < 0) {
usb_autosuspend_device(dev);
+ mutex_unlock(&hcd->bandwidth_mutex);
goto free_interfaces;
}
dev->actconfig = cp;
if (!cp) {
usb_set_device_state(dev, USB_STATE_ADDRESS);
- usb_hcd_check_bandwidth(dev, NULL, NULL);
+ usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
usb_autosuspend_device(dev);
+ mutex_unlock(&hcd->bandwidth_mutex);
goto free_interfaces;
}
+ mutex_unlock(&hcd->bandwidth_mutex);
usb_set_device_state(dev, USB_STATE_CONFIGURED);
/* Initialize the new interface structures and the