diff options
| -rw-r--r-- | payloads/libpayload/drivers/usb/ehci_rh.c | 39 |
1 files changed, 32 insertions, 7 deletions
diff --git a/payloads/libpayload/drivers/usb/ehci_rh.c b/payloads/libpayload/drivers/usb/ehci_rh.c index 5eaeeb690e..5f0db94b8d 100644 --- a/payloads/libpayload/drivers/usb/ehci_rh.c +++ b/payloads/libpayload/drivers/usb/ehci_rh.c @@ -54,14 +54,19 @@ static void ehci_rh_hand_over_port (usbdev_t *dev, int port) { volatile portsc_t *p = &(RH_INST(dev)->ports[port]); + volatile portsc_t tmp; printf("giving up port %x, it's USB1\n", port+1); /* Lowspeed device. Hand over to companion */ - p->port_owner = 1; + tmp = *p; + tmp.port_owner = 1; + *p = tmp; do {} while (!p->conn_status_change); /* RW/C register, so clear it by writing 1 */ - p->conn_status_change = 1; + tmp = *p; + tmp.conn_status_change = 1; + *p = tmp; return; } @@ -69,6 +74,7 @@ static void ehci_rh_scanport (usbdev_t *dev, int port) { volatile portsc_t *p = &(RH_INST(dev)->ports[port]); + volatile portsc_t tmp; if (RH_INST(dev)->devices[port]!=-1) { printf("Unregister device at port %x\n", port+1); usb_detach_device(dev->controller, RH_INST(dev)->devices[port]); @@ -81,10 +87,22 @@ ehci_rh_scanport (usbdev_t *dev, int port) ehci_rh_hand_over_port(dev, port); return; } - p->port_enable = 0; - p->port_reset = 1; + + /* Deassert enable, assert reset. These must change + * atomically. + */ + tmp = *p; + tmp.port_enable = 0; + tmp.port_reset = 1; + *p = tmp; + + /* Wait a bit while reset is active. */ mdelay(50); - p->port_reset = 0; + + /* Deassert reset. */ + tmp.port_reset = 0; + *p = tmp; + /* Wait for flag change to finish. The controller might take a while */ while (p->port_reset) ; if (!p->port_enable) { @@ -95,7 +113,9 @@ ehci_rh_scanport (usbdev_t *dev, int port) RH_INST(dev)->devices[port] = usb_attach_device(dev->controller, dev->address, port, 2); } /* RW/C register, so clear it by writing 1 */ - p->conn_status_change = 1; + tmp = *p; + tmp.conn_status_change = 1; + *p = tmp; } static int @@ -122,6 +142,8 @@ void ehci_rh_init (usbdev_t *dev) { int i; + volatile portsc_t *p; + volatile portsc_t tmp; dev->destroy = ehci_rh_destroy; dev->poll = ehci_rh_poll; @@ -135,8 +157,11 @@ ehci_rh_init (usbdev_t *dev) RH_INST(dev)->devices = malloc(RH_INST(dev)->n_ports * sizeof(int)); for (i=0; i < RH_INST(dev)->n_ports; i++) { + p = &(RH_INST(dev)->ports[i]); RH_INST(dev)->devices[i] = -1; - RH_INST(dev)->ports[i].pp = 1; + tmp = *p; + tmp.pp = 1; + *p = tmp; } dev->address = 0; |