diff options
| author | Mika Westerberg <mika.westerberg@linux.intel.com> | 2022-12-27 12:55:26 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-04-05 12:23:37 +0300 |
| commit | 06e04b450bb49f34d859f49c50d6609dd2008f2f (patch) | |
| tree | 164063980d6f76de4e375dff3701db5fb8dc2c7e | |
| parent | 32fa53c27ea36b62e4444e7e859a5d03f6189d9e (diff) | |
| download | linux-06e04b450bb49f34d859f49c50d6609dd2008f2f.tar.xz | |
thunderbolt: Use scale field when allocating USB3 bandwidth
commit c82510b1d87bdebfe916048857d2ef46f1778aa5 upstream.
When tunneling aggregated USB3 (20 Gb/s) the bandwidth values that are
programmed to the ADP_USB3_CS_2 go higher than 4096 and that does not
fit anymore to the 12-bit field. Fix this by scaling the value using
the scale field accordingly.
Fixes: 3b1d8d577ca8 ("thunderbolt: Implement USB3 bandwidth negotiation routines")
Cc: stable@vger.kernel.org
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/thunderbolt/usb4.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/thunderbolt/usb4.c b/drivers/thunderbolt/usb4.c index 0b3a77ade04d..5b45c45e7c5b 100644 --- a/drivers/thunderbolt/usb4.c +++ b/drivers/thunderbolt/usb4.c @@ -1636,18 +1636,30 @@ static int usb4_usb3_port_write_allocated_bandwidth(struct tb_port *port, int downstream_bw) { u32 val, ubw, dbw, scale; - int ret; + int ret, max_bw; - /* Read the used scale, hardware default is 0 */ - ret = tb_port_read(port, &scale, TB_CFG_PORT, - port->cap_adap + ADP_USB3_CS_3, 1); + /* Figure out suitable scale */ + scale = 0; + max_bw = max(upstream_bw, downstream_bw); + while (scale < 64) { + if (mbps_to_usb3_bw(max_bw, scale) < 4096) + break; + scale++; + } + + if (WARN_ON(scale >= 64)) + return -EINVAL; + + ret = tb_port_write(port, &scale, TB_CFG_PORT, + port->cap_adap + ADP_USB3_CS_3, 1); if (ret) return ret; - scale &= ADP_USB3_CS_3_SCALE_MASK; ubw = mbps_to_usb3_bw(upstream_bw, scale); dbw = mbps_to_usb3_bw(downstream_bw, scale); + tb_port_dbg(port, "scaled bandwidth %u/%u, scale %u\n", ubw, dbw, scale); + ret = tb_port_read(port, &val, TB_CFG_PORT, port->cap_adap + ADP_USB3_CS_2, 1); if (ret) |