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| author | Johan Hovold <johan@kernel.org> | 2021-07-05 10:20:11 +0200 |
|---|---|---|
| committer | Johan Hovold <johan@kernel.org> | 2021-07-30 17:19:31 +0200 |
| commit | ba4bbdabecd11530dca78dbae3ee7e51ffdc0a06 (patch) | |
| tree | 249f0f24d574f49cc45fdfa105b172e413a7ee4e /drivers/usb/serial | |
| parent | 2d9a00705910ccea2dc5d9cba5469ff2de72fc87 (diff) | |
| download | linux-ba4bbdabecd11530dca78dbae3ee7e51ffdc0a06.tar.gz linux-ba4bbdabecd11530dca78dbae3ee7e51ffdc0a06.tar.bz2 linux-ba4bbdabecd11530dca78dbae3ee7e51ffdc0a06.zip | |
USB: serial: cp210x: fix flow-control error handling
Make sure that the driver crtscts state is not updated in the unlikely
event that the flow-control request fails. Not doing so could break RTS
control.
Fixes: 5951b8508855 ("USB: serial: cp210x: suppress modem-control errors")
Cc: stable@vger.kernel.org # 5.11
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'drivers/usb/serial')
| -rw-r--r-- | drivers/usb/serial/cp210x.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/usb/serial/cp210x.c b/drivers/usb/serial/cp210x.c index ad6aeb44f3e6..d48bed5782a5 100644 --- a/drivers/usb/serial/cp210x.c +++ b/drivers/usb/serial/cp210x.c @@ -1190,6 +1190,7 @@ static void cp210x_set_flow_control(struct tty_struct *tty, struct cp210x_flow_ctl flow_ctl; u32 flow_repl; u32 ctl_hs; + bool crtscts; int ret; /* @@ -1249,14 +1250,14 @@ static void cp210x_set_flow_control(struct tty_struct *tty, flow_repl |= CP210X_SERIAL_RTS_FLOW_CTL; else flow_repl |= CP210X_SERIAL_RTS_INACTIVE; - port_priv->crtscts = true; + crtscts = true; } else { ctl_hs &= ~CP210X_SERIAL_CTS_HANDSHAKE; if (port_priv->rts) flow_repl |= CP210X_SERIAL_RTS_ACTIVE; else flow_repl |= CP210X_SERIAL_RTS_INACTIVE; - port_priv->crtscts = false; + crtscts = false; } if (I_IXOFF(tty)) { @@ -1279,8 +1280,12 @@ static void cp210x_set_flow_control(struct tty_struct *tty, flow_ctl.ulControlHandshake = cpu_to_le32(ctl_hs); flow_ctl.ulFlowReplace = cpu_to_le32(flow_repl); - cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl, + ret = cp210x_write_reg_block(port, CP210X_SET_FLOW, &flow_ctl, sizeof(flow_ctl)); + if (ret) + goto out_unlock; + + port_priv->crtscts = crtscts; out_unlock: mutex_unlock(&port_priv->mutex); } |