diff options
Diffstat (limited to 'drivers/usb/dwc3/core.c')
| -rw-r--r-- | drivers/usb/dwc3/core.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index d55d84db2be7..83e382b4ae28 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -63,6 +63,48 @@ static char *maximum_speed = "super"; module_param(maximum_speed, charp, 0); MODULE_PARM_DESC(maximum_speed, "Maximum supported speed."); +/* -------------------------------------------------------------------------- */ + +#define DWC3_DEVS_POSSIBLE 32 + +static DECLARE_BITMAP(dwc3_devs, DWC3_DEVS_POSSIBLE); + +int dwc3_get_device_id(void) +{ + int id; + +again: + id = find_first_zero_bit(dwc3_devs, DWC3_DEVS_POSSIBLE); + if (id < DWC3_DEVS_POSSIBLE) { + int old; + + old = test_and_set_bit(id, dwc3_devs); + if (old) + goto again; + } else { + pr_err("dwc3: no space for new device\n"); + id = -ENOMEM; + } + + return 0; +} +EXPORT_SYMBOL_GPL(dwc3_get_device_id); + +void dwc3_put_device_id(int id) +{ + int ret; + + if (id < 0) + return; + + ret = test_bit(id, dwc3_devs); + WARN(!ret, "dwc3: ID %d not in use\n", id); + clear_bit(id, dwc3_devs); +} +EXPORT_SYMBOL_GPL(dwc3_put_device_id); + +/* -------------------------------------------------------------------------- */ + /** * dwc3_core_soft_reset - Issues core soft reset and PHY reset * @dwc: pointer to our context structure |