diff options
Diffstat (limited to 'drivers/thunderbolt/switch.c')
-rw-r--r-- | drivers/thunderbolt/switch.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index 6d193a230cf4..b31b8cef301d 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -53,6 +53,92 @@ static void tb_dump_port(struct tb *tb, struct tb_regs_port_header *port) } /** + * tb_port_state() - get connectedness state of a port + * + * The port must have a TB_CAP_PHY (i.e. it should be a real port). + * + * Return: Returns an enum tb_port_state on success or an error code on failure. + */ +static int tb_port_state(struct tb_port *port) +{ + struct tb_cap_phy phy; + int res; + if (port->cap_phy == 0) { + tb_port_WARN(port, "does not have a PHY\n"); + return -EINVAL; + } + res = tb_port_read(port, &phy, TB_CFG_PORT, port->cap_phy, 2); + if (res) + return res; + return phy.state; +} + +/** + * tb_wait_for_port() - wait for a port to become ready + * + * Wait up to 1 second for a port to reach state TB_PORT_UP. If + * wait_if_unplugged is set then we also wait if the port is in state + * TB_PORT_UNPLUGGED (it takes a while for the device to be registered after + * switch resume). Otherwise we only wait if a device is registered but the link + * has not yet been established. + * + * Return: Returns an error code on failure. Returns 0 if the port is not + * connected or failed to reach state TB_PORT_UP within one second. Returns 1 + * if the port is connected and in state TB_PORT_UP. + */ +int tb_wait_for_port(struct tb_port *port, bool wait_if_unplugged) +{ + int retries = 10; + int state; + if (!port->cap_phy) { + tb_port_WARN(port, "does not have PHY\n"); + return -EINVAL; + } + if (tb_is_upstream_port(port)) { + tb_port_WARN(port, "is the upstream port\n"); + return -EINVAL; + } + + while (retries--) { + state = tb_port_state(port); + if (state < 0) + return state; + if (state == TB_PORT_DISABLED) { + tb_port_info(port, "is disabled (state: 0)\n"); + return 0; + } + if (state == TB_PORT_UNPLUGGED) { + if (wait_if_unplugged) { + /* used during resume */ + tb_port_info(port, + "is unplugged (state: 7), retrying...\n"); + msleep(100); + continue; + } + tb_port_info(port, "is unplugged (state: 7)\n"); + return 0; + } + if (state == TB_PORT_UP) { + tb_port_info(port, + "is connected, link is up (state: 2)\n"); + return 1; + } + + /* + * After plug-in the state is TB_PORT_CONNECTING. Give it some + * time. + */ + tb_port_info(port, + "is connected, link is not up (state: %d), retrying...\n", + state); + msleep(100); + } + tb_port_warn(port, + "failed to reach state TB_PORT_UP. Ignoring port...\n"); + return 0; +} + +/** * tb_init_port() - initialize a port * * This is a helper method for tb_switch_alloc. Does not check or initialize @@ -63,6 +149,7 @@ static void tb_dump_port(struct tb *tb, struct tb_regs_port_header *port) static int tb_init_port(struct tb_switch *sw, u8 port_nr) { int res; + int cap; struct tb_port *port = &sw->ports[port_nr]; port->sw = sw; port->port = port_nr; @@ -71,6 +158,16 @@ static int tb_init_port(struct tb_switch *sw, u8 port_nr) if (res) return res; + /* Port 0 is the switch itself and has no PHY. */ + if (port->config.type == TB_TYPE_PORT && port_nr != 0) { + cap = tb_find_cap(port, TB_CFG_PORT, TB_CAP_PHY); + + if (cap > 0) + port->cap_phy = cap; + else + tb_port_WARN(port, "non switch port without a PHY\n"); + } + tb_dump_port(sw->tb, &port->config); /* TODO: Read dual link port, DP port and more from EEPROM. */ |