diff options
Diffstat (limited to 'drivers/thunderbolt/usb4.c')
| -rw-r--r-- | drivers/thunderbolt/usb4.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index f8f0d24ff6e4..4b35898aa216 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -1113,6 +1113,45 @@ int usb4_port_hotplug_enable(struct tb_port *port) return tb_port_write(port, &val, TB_CFG_PORT, ADP_CS_5, 1); } +/** + * usb4_port_reset() - Issue downstream port reset + * @port: USB4 port to reset + * + * Issues downstream port reset to @port. + */ +int usb4_port_reset(struct tb_port *port) +{ + int ret; + u32 val; + + if (!port->cap_usb4) + return -EINVAL; + + ret = tb_port_read(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + val |= PORT_CS_19_DPR; + + ret = tb_port_write(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + fsleep(10000); + + ret = tb_port_read(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); + if (ret) + return ret; + + val &= ~PORT_CS_19_DPR; + + return tb_port_write(port, &val, TB_CFG_PORT, + port->cap_usb4 + PORT_CS_19, 1); +} + static int usb4_port_set_configured(struct tb_port *port, bool configured) { int ret; |