| Message ID | 20240320073927.1641788-6-lk@c--e.de |
|---|---|
| State | New |
| Headers | show |
| Series | Fix various races in UCSI | expand |
On Wed, Mar 20, 2024 at 08:39:26AM +0100, Christian A. Ehrhardt wrote: > Check the UCSI_CCI_RESET_COMPLETE complete flag before starting > another reset. Use a UCSI_SET_NOTIFICATION_ENABLE command to clear > the flag if it is set. > > Signed-off-by: Christian A. Ehrhardt <lk@c--e.de> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> > --- > drivers/usb/typec/ucsi/ucsi.c | 36 ++++++++++++++++++++++++++++++++++- > 1 file changed, 35 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c > index 63f340dbd867..85e507df7fa8 100644 > --- a/drivers/usb/typec/ucsi/ucsi.c > +++ b/drivers/usb/typec/ucsi/ucsi.c > @@ -1264,13 +1264,47 @@ static int ucsi_reset_connector(struct ucsi_connector *con, bool hard) > > static int ucsi_reset_ppm(struct ucsi *ucsi) > { > - u64 command = UCSI_PPM_RESET; > + u64 command; > unsigned long tmo; > u32 cci; > int ret; > > mutex_lock(&ucsi->ppm_lock); > > + ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci)); > + if (ret < 0) > + goto out; > + > + /* > + * If UCSI_CCI_RESET_COMPLETE is already set we must clear > + * the flag before we start another reset. Send a > + * UCSI_SET_NOTIFICATION_ENABLE command to achieve this. > + * Ignore a timeout and try the reset anyway if this fails. > + */ > + if (cci & UCSI_CCI_RESET_COMPLETE) { > + command = UCSI_SET_NOTIFICATION_ENABLE; > + ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command, > + sizeof(command)); > + if (ret < 0) > + goto out; > + > + tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS); > + do { > + ret = ucsi->ops->read(ucsi, UCSI_CCI, > + &cci, sizeof(cci)); > + if (ret < 0) > + goto out; > + if (cci & UCSI_CCI_COMMAND_COMPLETE) > + break; > + if (time_is_before_jiffies(tmo)) > + break; > + msleep(20); > + } while (1); > + > + WARN_ON(cci & UCSI_CCI_RESET_COMPLETE); > + } > + > + command = UCSI_PPM_RESET; > ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command, > sizeof(command)); > if (ret < 0) > -- > 2.40.1
diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 63f340dbd867..85e507df7fa8 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -1264,13 +1264,47 @@ static int ucsi_reset_connector(struct ucsi_connector *con, bool hard) static int ucsi_reset_ppm(struct ucsi *ucsi) { - u64 command = UCSI_PPM_RESET; + u64 command; unsigned long tmo; u32 cci; int ret; mutex_lock(&ucsi->ppm_lock); + ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci)); + if (ret < 0) + goto out; + + /* + * If UCSI_CCI_RESET_COMPLETE is already set we must clear + * the flag before we start another reset. Send a + * UCSI_SET_NOTIFICATION_ENABLE command to achieve this. + * Ignore a timeout and try the reset anyway if this fails. + */ + if (cci & UCSI_CCI_RESET_COMPLETE) { + command = UCSI_SET_NOTIFICATION_ENABLE; + ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command, + sizeof(command)); + if (ret < 0) + goto out; + + tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS); + do { + ret = ucsi->ops->read(ucsi, UCSI_CCI, + &cci, sizeof(cci)); + if (ret < 0) + goto out; + if (cci & UCSI_CCI_COMMAND_COMPLETE) + break; + if (time_is_before_jiffies(tmo)) + break; + msleep(20); + } while (1); + + WARN_ON(cci & UCSI_CCI_RESET_COMPLETE); + } + + command = UCSI_PPM_RESET; ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command, sizeof(command)); if (ret < 0)
Check the UCSI_CCI_RESET_COMPLETE complete flag before starting another reset. Use a UCSI_SET_NOTIFICATION_ENABLE command to clear the flag if it is set. Signed-off-by: Christian A. Ehrhardt <lk@c--e.de> --- drivers/usb/typec/ucsi/ucsi.c | 36 ++++++++++++++++++++++++++++++++++- 1 file changed, 35 insertions(+), 1 deletion(-)