diff options
author | Mika Westerberg <mika.westerberg@linux.intel.com> | 2020-06-29 20:21:07 +0300 |
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committer | Mika Westerberg <mika.westerberg@linux.intel.com> | 2020-09-03 12:21:07 +0300 |
commit | 6de057ef915f167dc6518910de3675ab061d2a50 (patch) | |
tree | bb6e759ca6fd908e4d8aedbc7c08dcdab9ab6105 | |
parent | 3c8b228d4371d0556d3d333d63df90172c2c7355 (diff) | |
download | linux-6de057ef915f167dc6518910de3675ab061d2a50.tar.bz2 |
thunderbolt: Introduce tb_switch_next_cap()
This is similar to tb_port_next_cap() but instead allows walking
capability list of a switch (router). Convert tb_switch_find_cap() and
tb_switch_find_vse_cap() to use this as well.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/thunderbolt/cap.c | 93 | ||||
-rw-r--r-- | drivers/thunderbolt/tb.h | 1 |
2 files changed, 64 insertions, 30 deletions
diff --git a/drivers/thunderbolt/cap.c b/drivers/thunderbolt/cap.c index c45b3a488412..6f571e912cf2 100644 --- a/drivers/thunderbolt/cap.c +++ b/drivers/thunderbolt/cap.c @@ -133,6 +133,50 @@ int tb_port_find_cap(struct tb_port *port, enum tb_port_cap cap) } /** + * tb_switch_next_cap() - Return next capability in the linked list + * @sw: Switch to find the capability for + * @offset: Previous capability offset (%0 for start) + * + * Finds dword offset of the next capability in router config space + * capability list and returns it. Passing %0 returns the first entry in + * the capability list. If no next capability is found returns %0. In case + * of failure returns negative errno. + */ +int tb_switch_next_cap(struct tb_switch *sw, unsigned int offset) +{ + struct tb_cap_any header; + int ret; + + if (!offset) + return sw->config.first_cap_offset; + + ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 2); + if (ret) + return ret; + + switch (header.basic.cap) { + case TB_SWITCH_CAP_TMU: + ret = header.basic.next; + break; + + case TB_SWITCH_CAP_VSE: + if (!header.extended_short.length) + ret = header.extended_long.next; + else + ret = header.extended_short.next; + break; + + default: + tb_sw_dbg(sw, "unknown capability %#x at %#x\n", + header.basic.cap, offset); + ret = -EINVAL; + break; + } + + return ret >= VSE_CAP_OFFSET_MAX ? 0 : ret; +} + +/** * tb_switch_find_cap() - Find switch capability * @sw Switch to find the capability for * @cap: Capability to look @@ -143,21 +187,23 @@ int tb_port_find_cap(struct tb_port *port, enum tb_port_cap cap) */ int tb_switch_find_cap(struct tb_switch *sw, enum tb_switch_cap cap) { - int offset = sw->config.first_cap_offset; + int offset = 0; - while (offset > 0 && offset < CAP_OFFSET_MAX) { + do { struct tb_cap_any header; int ret; + offset = tb_switch_next_cap(sw, offset); + if (offset < 0) + return offset; + ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 1); if (ret) return ret; if (header.basic.cap == cap) return offset; - - offset = header.basic.next; - } + } while (offset); return -ENOENT; } @@ -174,37 +220,24 @@ int tb_switch_find_cap(struct tb_switch *sw, enum tb_switch_cap cap) */ int tb_switch_find_vse_cap(struct tb_switch *sw, enum tb_switch_vse_cap vsec) { - struct tb_cap_any header; - int offset; - - offset = tb_switch_find_cap(sw, TB_SWITCH_CAP_VSE); - if (offset < 0) - return offset; + int offset = 0; - while (offset > 0 && offset < VSE_CAP_OFFSET_MAX) { + do { + struct tb_cap_any header; int ret; - ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 2); + offset = tb_switch_next_cap(sw, offset); + if (offset < 0) + return offset; + + ret = tb_sw_read(sw, &header, TB_CFG_SWITCH, offset, 1); if (ret) return ret; - /* - * Extended vendor specific capabilities come in two - * flavors: short and long. The latter is used when - * offset is over 0xff. - */ - if (offset >= CAP_OFFSET_MAX) { - if (header.extended_long.vsec_id == vsec) - return offset; - offset = header.extended_long.next; - } else { - if (header.extended_short.vsec_id == vsec) - return offset; - if (!header.extended_short.length) - return -ENOENT; - offset = header.extended_short.next; - } - } + if (header.extended_short.cap == TB_SWITCH_CAP_VSE && + header.extended_short.vsec_id == vsec) + return offset; + } while (offset); return -ENOENT; } diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h index 54e8fad78bee..a1d5de53a349 100644 --- a/drivers/thunderbolt/tb.h +++ b/drivers/thunderbolt/tb.h @@ -822,6 +822,7 @@ int tb_port_get_link_speed(struct tb_port *port); int tb_switch_find_vse_cap(struct tb_switch *sw, enum tb_switch_vse_cap vsec); int tb_switch_find_cap(struct tb_switch *sw, enum tb_switch_cap cap); +int tb_switch_next_cap(struct tb_switch *sw, unsigned int offset); int tb_port_find_cap(struct tb_port *port, enum tb_port_cap cap); int tb_port_next_cap(struct tb_port *port, unsigned int offset); bool tb_port_is_enabled(struct tb_port *port); |