From 0ff0705a2ef2929e9326c95df48bdbebb0dafaad Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 9 Aug 2020 16:19:01 +0200 Subject: usb: typec: ucsi: Fix AB BA lock inversion Lockdep reports an AB BA lock inversion between ucsi_init() and ucsi_handle_connector_change(): AB order: 1. ucsi_init takes ucsi->ppm_lock (it runs with that locked for the duration of the function) 2. usci_init eventually end up calling ucsi_register_displayport, which takes ucsi_connector->lock BA order: 1. ucsi_handle_connector_change work is started, takes ucsi_connector->lock 2. ucsi_handle_connector_change calls ucsi_send_command which takes ucsi->ppm_lock The ppm_lock really only needs to be hold during 2 functions: ucsi_reset_ppm() and ucsi_run_command(). This commit fixes the AB BA lock inversion by making ucsi_init drop the ucsi->ppm_lock before it starts registering ports; and replacing any ucsi_run_command() calls after this point with ucsi_send_command() (which is a wrapper around run_command taking the lock while handling the command). Some of the replacing of ucsi_run_command with ucsi_send_command in the helpers used during port registration also fixes a number of code paths after registration which call ucsi_run_command() without holding the ppm_lock: 1. ucsi_altmode_update_active() call in ucsi/displayport.c 2. ucsi_register_altmodes() call from ucsi_handle_connector_change() (through ucsi_partner_change()) Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede Acked-by: Heikki Krogerus Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200809141904.4317-2-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/ucsi/ucsi.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-) (limited to 'drivers/usb/typec') diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index affd024190c9..05babc09f3a8 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -205,7 +205,7 @@ void ucsi_altmode_update_active(struct ucsi_connector *con) int i; command = UCSI_GET_CURRENT_CAM | UCSI_CONNECTOR_NUMBER(con->num); - ret = ucsi_run_command(con->ucsi, command, &cur, sizeof(cur)); + ret = ucsi_send_command(con->ucsi, command, &cur, sizeof(cur)); if (ret < 0) { if (con->ucsi->version > 0x0100) { dev_err(con->ucsi->dev, @@ -354,7 +354,7 @@ ucsi_register_altmodes_nvidia(struct ucsi_connector *con, u8 recipient) command |= UCSI_GET_ALTMODE_RECIPIENT(recipient); command |= UCSI_GET_ALTMODE_CONNECTOR_NUMBER(con->num); command |= UCSI_GET_ALTMODE_OFFSET(i); - len = ucsi_run_command(con->ucsi, command, &alt, sizeof(alt)); + len = ucsi_send_command(con->ucsi, command, &alt, sizeof(alt)); /* * We are collecting all altmodes first and then registering. * Some type-C device will return zero length data beyond last @@ -431,7 +431,7 @@ static int ucsi_register_altmodes(struct ucsi_connector *con, u8 recipient) command |= UCSI_GET_ALTMODE_RECIPIENT(recipient); command |= UCSI_GET_ALTMODE_CONNECTOR_NUMBER(con->num); command |= UCSI_GET_ALTMODE_OFFSET(i); - len = ucsi_run_command(con->ucsi, command, alt, sizeof(alt)); + len = ucsi_send_command(con->ucsi, command, alt, sizeof(alt)); if (len <= 0) return len; @@ -904,7 +904,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) /* Get connector capability */ command = UCSI_GET_CONNECTOR_CAPABILITY; command |= UCSI_CONNECTOR_NUMBER(con->num); - ret = ucsi_run_command(ucsi, command, &con->cap, sizeof(con->cap)); + ret = ucsi_send_command(ucsi, command, &con->cap, sizeof(con->cap)); if (ret < 0) return ret; @@ -953,8 +953,7 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) /* Get the status */ command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num); - ret = ucsi_run_command(ucsi, command, &con->status, - sizeof(con->status)); + ret = ucsi_send_command(ucsi, command, &con->status, sizeof(con->status)); if (ret < 0) { dev_err(ucsi->dev, "con%d: failed to get status\n", con->num); return 0; @@ -1044,6 +1043,8 @@ static int ucsi_init(struct ucsi *ucsi) goto err_reset; } + mutex_unlock(&ucsi->ppm_lock); + /* Register all connectors */ for (i = 0; i < ucsi->cap.num_connectors; i++) { ret = ucsi_register_port(ucsi, i); @@ -1054,12 +1055,10 @@ static int ucsi_init(struct ucsi *ucsi) /* Enable all notifications */ ucsi->ntfy = UCSI_ENABLE_NTFY_ALL; command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy; - ret = ucsi_run_command(ucsi, command, NULL, 0); + ret = ucsi_send_command(ucsi, command, NULL, 0); if (ret < 0) goto err_unregister; - mutex_unlock(&ucsi->ppm_lock); - return 0; err_unregister: @@ -1071,6 +1070,7 @@ err_unregister: con->port = NULL; } + mutex_lock(&ucsi->ppm_lock); err_reset: ucsi_reset_ppm(ucsi); err: -- cgit v1.2.3 From 7e90057f125c8c852940b848e06e7a72f050fc6f Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 9 Aug 2020 16:19:02 +0200 Subject: usb: typec: ucsi: Fix 2 unlocked ucsi_run_command calls Fix 2 unlocked ucsi_run_command calls: 1. ucsi_handle_connector_change() contains one ucsi_send_command() call, which takes the ppm_lock for it; and one ucsi_run_command() call which relies on the caller have taking the ppm_lock. ucsi_handle_connector_change() does not take the lock, so the second (ucsi_run_command) calls should also be ucsi_send_command(). 2. ucsi_get_pdos() gets called from ucsi_handle_connector_change() which does not hold the ppm_lock, so it also must use ucsi_send_command(). This commit also adds a WARN_ON(!mutex_is_locked(&ucsi->ppm_lock)); to ucsi_run_command() to avoid similar problems getting re-introduced in the future. Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede Acked-by: Heikki Krogerus Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200809141904.4317-3-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/ucsi/ucsi.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'drivers/usb/typec') diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 05babc09f3a8..3b208ea59a50 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -152,6 +152,8 @@ static int ucsi_run_command(struct ucsi *ucsi, u64 command, u8 length; int ret; + WARN_ON(!mutex_is_locked(&ucsi->ppm_lock)); + ret = ucsi_exec_command(ucsi, command); if (ret < 0) return ret; @@ -502,7 +504,7 @@ static void ucsi_get_pdos(struct ucsi_connector *con, int is_partner) command |= UCSI_GET_PDOS_PARTNER_PDO(is_partner); command |= UCSI_GET_PDOS_NUM_PDOS(UCSI_MAX_PDOS - 1); command |= UCSI_GET_PDOS_SRC_PDOS; - ret = ucsi_run_command(ucsi, command, con->src_pdos, + ret = ucsi_send_command(ucsi, command, con->src_pdos, sizeof(con->src_pdos)); if (ret < 0) { dev_err(ucsi->dev, "UCSI_GET_PDOS failed (%d)\n", ret); @@ -681,7 +683,7 @@ static void ucsi_handle_connector_change(struct work_struct *work) */ command = UCSI_GET_CAM_SUPPORTED; command |= UCSI_CONNECTOR_NUMBER(con->num); - ucsi_run_command(con->ucsi, command, NULL, 0); + ucsi_send_command(con->ucsi, command, NULL, 0); } if (con->status.change & UCSI_CONSTAT_PARTNER_CHANGE) -- cgit v1.2.3 From 25794e3079d2a98547b6bf5764ef0240aa89b798 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 9 Aug 2020 16:19:03 +0200 Subject: usb: typec: ucsi: Rework ppm_lock handling The ppm_lock really only needs to be hold during 2 functions: ucsi_reset_ppm() and ucsi_run_command(). Push the taking of the lock down into these 2 functions, renaming ucsi_run_command() to ucsi_send_command() which was an existing wrapper already taking the lock for its callers. This simplifies things for the callers and removes the difference between ucsi_send_command() and ucsi_run_command() which has led to various locking bugs in the past. Cc: stable@vger.kernel.org Signed-off-by: Hans de Goede Acked-by: Heikki Krogerus Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200809141904.4317-4-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/ucsi/ucsi.c | 56 +++++++++++++++++-------------------------- 1 file changed, 22 insertions(+), 34 deletions(-) (limited to 'drivers/usb/typec') diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 3b208ea59a50..8a35144211e5 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -146,42 +146,33 @@ static int ucsi_exec_command(struct ucsi *ucsi, u64 cmd) return UCSI_CCI_LENGTH(cci); } -static int ucsi_run_command(struct ucsi *ucsi, u64 command, - void *data, size_t size) +int ucsi_send_command(struct ucsi *ucsi, u64 command, + void *data, size_t size) { u8 length; int ret; - WARN_ON(!mutex_is_locked(&ucsi->ppm_lock)); + mutex_lock(&ucsi->ppm_lock); ret = ucsi_exec_command(ucsi, command); if (ret < 0) - return ret; + goto out; length = ret; if (data) { ret = ucsi->ops->read(ucsi, UCSI_MESSAGE_IN, data, size); if (ret) - return ret; + goto out; } ret = ucsi_acknowledge_command(ucsi); if (ret) - return ret; - - return length; -} + goto out; -int ucsi_send_command(struct ucsi *ucsi, u64 command, - void *retval, size_t size) -{ - int ret; - - mutex_lock(&ucsi->ppm_lock); - ret = ucsi_run_command(ucsi, command, retval, size); + ret = length; +out: mutex_unlock(&ucsi->ppm_lock); - return ret; } EXPORT_SYMBOL_GPL(ucsi_send_command); @@ -738,20 +729,24 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) u32 cci; int ret; + mutex_lock(&ucsi->ppm_lock); + ret = ucsi->ops->async_write(ucsi, UCSI_CONTROL, &command, sizeof(command)); if (ret < 0) - return ret; + goto out; tmo = jiffies + msecs_to_jiffies(UCSI_TIMEOUT_MS); do { - if (time_is_before_jiffies(tmo)) - return -ETIMEDOUT; + if (time_is_before_jiffies(tmo)) { + ret = -ETIMEDOUT; + goto out; + } ret = ucsi->ops->read(ucsi, UCSI_CCI, &cci, sizeof(cci)); if (ret) - return ret; + goto out; /* If the PPM is still doing something else, reset it again. */ if (cci & ~UCSI_CCI_RESET_COMPLETE) { @@ -759,13 +754,15 @@ static int ucsi_reset_ppm(struct ucsi *ucsi) &command, sizeof(command)); if (ret < 0) - return ret; + goto out; } msleep(20); } while (!(cci & UCSI_CCI_RESET_COMPLETE)); - return 0; +out: + mutex_unlock(&ucsi->ppm_lock); + return ret; } static int ucsi_role_cmd(struct ucsi_connector *con, u64 command) @@ -777,9 +774,7 @@ static int ucsi_role_cmd(struct ucsi_connector *con, u64 command) u64 c; /* PPM most likely stopped responding. Resetting everything. */ - mutex_lock(&con->ucsi->ppm_lock); ucsi_reset_ppm(con->ucsi); - mutex_unlock(&con->ucsi->ppm_lock); c = UCSI_SET_NOTIFICATION_ENABLE | con->ucsi->ntfy; ucsi_send_command(con->ucsi, c, NULL, 0); @@ -1010,8 +1005,6 @@ static int ucsi_init(struct ucsi *ucsi) int ret; int i; - mutex_lock(&ucsi->ppm_lock); - /* Reset the PPM */ ret = ucsi_reset_ppm(ucsi); if (ret) { @@ -1022,13 +1015,13 @@ static int ucsi_init(struct ucsi *ucsi) /* Enable basic notifications */ ucsi->ntfy = UCSI_ENABLE_NTFY_CMD_COMPLETE | UCSI_ENABLE_NTFY_ERROR; command = UCSI_SET_NOTIFICATION_ENABLE | ucsi->ntfy; - ret = ucsi_run_command(ucsi, command, NULL, 0); + ret = ucsi_send_command(ucsi, command, NULL, 0); if (ret < 0) goto err_reset; /* Get PPM capabilities */ command = UCSI_GET_CAPABILITY; - ret = ucsi_run_command(ucsi, command, &ucsi->cap, sizeof(ucsi->cap)); + ret = ucsi_send_command(ucsi, command, &ucsi->cap, sizeof(ucsi->cap)); if (ret < 0) goto err_reset; @@ -1045,8 +1038,6 @@ static int ucsi_init(struct ucsi *ucsi) goto err_reset; } - mutex_unlock(&ucsi->ppm_lock); - /* Register all connectors */ for (i = 0; i < ucsi->cap.num_connectors; i++) { ret = ucsi_register_port(ucsi, i); @@ -1072,12 +1063,9 @@ err_unregister: con->port = NULL; } - mutex_lock(&ucsi->ppm_lock); err_reset: ucsi_reset_ppm(ucsi); err: - mutex_unlock(&ucsi->ppm_lock); - return ret; } -- cgit v1.2.3 From bed97b30968ba354035a020989df0623e52b5536 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Sun, 9 Aug 2020 16:19:04 +0200 Subject: usb: typec: ucsi: Hold con->lock for the entire duration of ucsi_register_port() Commit 081da1325d35 ("usb: typec: ucsi: displayport: Fix a potential race during registration") made the ucsi code hold con->lock in ucsi_register_displayport(). But we really don't want any interactions with the connector to run before the port-registration process is fully complete. This commit moves the taking of con->lock from ucsi_register_displayport() into ucsi_register_port() to achieve this. Cc: stable@vger.kernel.org Fixes: 081da1325d35 ("usb: typec: ucsi: displayport: Fix a potential race during registration") Signed-off-by: Hans de Goede Acked-by: Heikki Krogerus Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20200809141904.4317-5-hdegoede@redhat.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/ucsi/displayport.c | 9 +-------- drivers/usb/typec/ucsi/ucsi.c | 31 ++++++++++++++++++++++--------- 2 files changed, 23 insertions(+), 17 deletions(-) (limited to 'drivers/usb/typec') diff --git a/drivers/usb/typec/ucsi/displayport.c b/drivers/usb/typec/ucsi/displayport.c index 048381c058a5..261131c9e37c 100644 --- a/drivers/usb/typec/ucsi/displayport.c +++ b/drivers/usb/typec/ucsi/displayport.c @@ -288,8 +288,6 @@ struct typec_altmode *ucsi_register_displayport(struct ucsi_connector *con, struct typec_altmode *alt; struct ucsi_dp *dp; - mutex_lock(&con->lock); - /* We can't rely on the firmware with the capabilities. */ desc->vdo |= DP_CAP_DP_SIGNALING | DP_CAP_RECEPTACLE; @@ -298,15 +296,12 @@ struct typec_altmode *ucsi_register_displayport(struct ucsi_connector *con, desc->vdo |= all_assignments << 16; alt = typec_port_register_altmode(con->port, desc); - if (IS_ERR(alt)) { - mutex_unlock(&con->lock); + if (IS_ERR(alt)) return alt; - } dp = devm_kzalloc(&alt->dev, sizeof(*dp), GFP_KERNEL); if (!dp) { typec_unregister_altmode(alt); - mutex_unlock(&con->lock); return ERR_PTR(-ENOMEM); } @@ -319,7 +314,5 @@ struct typec_altmode *ucsi_register_displayport(struct ucsi_connector *con, alt->ops = &ucsi_displayport_ops; typec_altmode_set_drvdata(alt, dp); - mutex_unlock(&con->lock); - return alt; } diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 8a35144211e5..e680fcfdee60 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -898,12 +898,15 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) con->num = index + 1; con->ucsi = ucsi; + /* Delay other interactions with the con until registration is complete */ + mutex_lock(&con->lock); + /* Get connector capability */ command = UCSI_GET_CONNECTOR_CAPABILITY; command |= UCSI_CONNECTOR_NUMBER(con->num); ret = ucsi_send_command(ucsi, command, &con->cap, sizeof(con->cap)); if (ret < 0) - return ret; + goto out; if (con->cap.op_mode & UCSI_CONCAP_OPMODE_DRP) cap->data = TYPEC_PORT_DRD; @@ -935,26 +938,32 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) ret = ucsi_register_port_psy(con); if (ret) - return ret; + goto out; /* Register the connector */ con->port = typec_register_port(ucsi->dev, cap); - if (IS_ERR(con->port)) - return PTR_ERR(con->port); + if (IS_ERR(con->port)) { + ret = PTR_ERR(con->port); + goto out; + } /* Alternate modes */ ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_CON); - if (ret) + if (ret) { dev_err(ucsi->dev, "con%d: failed to register alt modes\n", con->num); + goto out; + } /* Get the status */ command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num); ret = ucsi_send_command(ucsi, command, &con->status, sizeof(con->status)); if (ret < 0) { dev_err(ucsi->dev, "con%d: failed to get status\n", con->num); - return 0; + ret = 0; + goto out; } + ret = 0; /* ucsi_send_command() returns length on success */ switch (UCSI_CONSTAT_PARTNER_TYPE(con->status.flags)) { case UCSI_CONSTAT_PARTNER_TYPE_UFP: @@ -979,17 +988,21 @@ static int ucsi_register_port(struct ucsi *ucsi, int index) if (con->partner) { ret = ucsi_register_altmodes(con, UCSI_RECIPIENT_SOP); - if (ret) + if (ret) { dev_err(ucsi->dev, "con%d: failed to register alternate modes\n", con->num); - else + ret = 0; + } else { ucsi_altmode_update_active(con); + } } trace_ucsi_register_port(con->num, &con->status); - return 0; +out: + mutex_unlock(&con->lock); + return ret; } /** -- cgit v1.2.3 From 23e26d0577535f5ffe4ff8ed6d06e009553c0bca Mon Sep 17 00:00:00 2001 From: Badhri Jagan Sridharan Date: Mon, 17 Aug 2020 11:46:01 -0700 Subject: usb: typec: tcpm: Fix Fix source hard reset response for TDA 2.3.1.1 and TDA 2.3.1.2 failures The patch addresses the compliance test failures while running TDA 2.3.1.1 and TDA 2.3.1.2 of the "PD Communications Engine USB PD Compliance MOI" test plan published in https://www.usb.org/usbc. For a product to be Type-C compliant, it's expected that these tests are run on usb.org certified Type-C compliance tester as mentioned in https://www.usb.org/usbc. While the purpose of TDA 2.3.1.1 and TDA 2.3.1.2 is to verify that the static and dynamic electrical capabilities of a Source meet the requirements for each PDO offered, while doing so, the tests also monitor that the timing of the VBUS waveform versus the messages meets the requirements for Hard Reset defined in PROT-PROC-HR-TSTR as mentioned in step 11 of TDA.2.3.1.1 and step 15 of TDA.2.3.1.2. TDB.2.2.13.1: PROT-PROC-HR-TSTR Procedure and Checks for Tester Originated Hard Reset Purpose: To perform the appropriate protocol checks relating to any circumstance in which the Hard Reset signal is sent by the Tester. UUT is behaving as source: The Tester sends a Hard Reset signal. 1. Check VBUS stays within present valid voltage range for tPSHardReset min (25ms) after last bit of Hard Reset signal. [PROT_PROC_HR_TSTR_1] 2. Check that VBUS starts to fall below present valid voltage range by tPSHardReset max (35ms). [PROT_PROC_HR_TSTR_2] 3. Check that VBUS reaches vSafe0V within tSafe0v max (650 ms). [PROT_PROC_HR_TSTR_3] 4. Check that VBUS starts rising to vSafe5V after a delay of tSrcRecover (0.66s - 1s) from reaching vSafe0V. [PROT_PROC_HR_TSTR_4] 5. Check that VBUS reaches vSafe5V within tSrcTurnOn max (275ms) of rising above vSafe0v max (0.8V). [PROT_PROC_HR_TSTR_5] Power Delivery Compliance Plan 139 6. Check that Source Capabilities are finished sending within tFirstSourceCap max (250ms) of VBUS reaching vSafe5v min. [PROT_PROC_HR_TSTR_6]. This is in line with 7.1.5 Response to Hard Resets of the USB Power Delivery Specification Revision 3.0, Version 1.2, "Hard Reset Signaling indicates a communication failure has occurred and the Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall drive VBUS to vSafe0V as shown in Figure 7-9. The USB connection May reset during a Hard Reset since the VBUS voltage will be less than vSafe5V for an extended period of time. After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. A Source Shall conform to the VCONN timing as specified in [USB Type-C 1.3]." With the above guidelines from the spec in mind, TCPM does not turn off VCONN while entering SRC_HARD_RESET_VBUS_OFF. The patch makes TCPM turn off VCONN while entering SRC_HARD_RESET_VBUS_OFF and turn it back on while entering SRC_HARD_RESET_VBUS_ON along with vbus instead of having VCONN on through hardreset. Also, the spec clearly states that "After establishing the vSafe0V voltage condition on VBUS", the Source Shall wait tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. TCPM does not conform to this requirement. If the TCPC driver calls tcpm_vbus_change with vbus off signal, TCPM right away enters SRC_HARD_RESET_VBUS_ON without waiting for tSrcRecover. For TCPC's which are buggy/does not call tcpm_vbus_change, TCPM assumes that the vsafe0v is instantaneous as TCPM only waits tSrcRecover instead of waiting for tSafe0v + tSrcRecover. This patch also fixes this behavior by making sure that TCPM waits for tSrcRecover before transitioning into SRC_HARD_RESET_VBUS_ON when tcpm_vbus_change is called by TCPC. When TCPC does not call tcpm_vbus_change, TCPM assumes the worst case i.e. tSafe0v + tSrcRecover before transitioning into SRC_HARD_RESET_VBUS_ON. Signed-off-by: Badhri Jagan Sridharan Reviewed-by: Guenter Roeck Reviewed-by: Heikki Krogerus Cc: stable Link: https://lore.kernel.org/r/20200817184601.1899929-1-badhri@google.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/typec/tcpm/tcpm.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) (limited to 'drivers/usb/typec') diff --git a/drivers/usb/typec/tcpm/tcpm.c b/drivers/usb/typec/tcpm/tcpm.c index 3ef37202ee37..a48e3f90d196 100644 --- a/drivers/usb/typec/tcpm/tcpm.c +++ b/drivers/usb/typec/tcpm/tcpm.c @@ -3372,13 +3372,31 @@ static void run_state_machine(struct tcpm_port *port) tcpm_set_state(port, SNK_HARD_RESET_SINK_OFF, 0); break; case SRC_HARD_RESET_VBUS_OFF: - tcpm_set_vconn(port, true); + /* + * 7.1.5 Response to Hard Resets + * Hard Reset Signaling indicates a communication failure has occurred and the + * Source Shall stop driving VCONN, Shall remove Rp from the VCONN pin and Shall + * drive VBUS to vSafe0V as shown in Figure 7-9. + */ + tcpm_set_vconn(port, false); tcpm_set_vbus(port, false); tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE, tcpm_data_role_for_source(port)); - tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER); + /* + * If tcpc fails to notify vbus off, TCPM will wait for PD_T_SAFE_0V + + * PD_T_SRC_RECOVER before turning vbus back on. + * From Table 7-12 Sequence Description for a Source Initiated Hard Reset: + * 4. Policy Engine waits tPSHardReset after sending Hard Reset Signaling and then + * tells the Device Policy Manager to instruct the power supply to perform a + * Hard Reset. The transition to vSafe0V Shall occur within tSafe0V (t2). + * 5. After tSrcRecover the Source applies power to VBUS in an attempt to + * re-establish communication with the Sink and resume USB Default Operation. + * The transition to vSafe5V Shall occur within tSrcTurnOn(t4). + */ + tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SAFE_0V + PD_T_SRC_RECOVER); break; case SRC_HARD_RESET_VBUS_ON: + tcpm_set_vconn(port, true); tcpm_set_vbus(port, true); port->tcpc->set_pd_rx(port->tcpc, true); tcpm_set_attached_state(port, true); @@ -3944,7 +3962,11 @@ static void _tcpm_pd_vbus_off(struct tcpm_port *port) tcpm_set_state(port, SNK_HARD_RESET_WAIT_VBUS, 0); break; case SRC_HARD_RESET_VBUS_OFF: - tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, 0); + /* + * After establishing the vSafe0V voltage condition on VBUS, the Source Shall wait + * tSrcRecover before re-applying VCONN and restoring VBUS to vSafe5V. + */ + tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER); break; case HARD_RESET_SEND: break; -- cgit v1.2.3