diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c index 310b5caeb05a..dff93fbd2dd6 100644 --- a/drivers/usb/typec/ucsi/ucsi.c +++ b/drivers/usb/typec/ucsi/ucsi.c @@ -53,7 +53,7 @@ static int ucsi_acknowledge_connector_change(struct ucsi *ucsi) ctrl = UCSI_ACK_CC_CI; ctrl |= UCSI_ACK_CONNECTOR_CHANGE; - return ucsi->ops->async_write(ucsi, UCSI_CONTROL, &ctrl, sizeof(ctrl)); + return ucsi->ops->sync_write(ucsi, UCSI_CONTROL, &ctrl, sizeof(ctrl)); } static int ucsi_exec_command(struct ucsi *ucsi, u64 command); @@ -648,20 +648,112 @@ static void ucsi_handle_connector_change(struct work_struct *work) struct ucsi_connector *con = container_of(work, struct ucsi_connector, work); struct ucsi *ucsi = con->ucsi; + struct ucsi_connector_status pre_ack_status; + struct ucsi_connector_status post_ack_status; enum typec_role role; + u16 inferred_changes; + u16 changed_flags; u64 command; int ret; mutex_lock(&con->lock); + /* + * Some/many PPMs have an issue where all fields in the change bitfield + * are cleared when an ACK is send. This will causes any change + * between GET_CONNECTOR_STATUS and ACK to be lost. + * + * We work around this by re-fetching the connector status afterwards. + * We then infer any changes that we see have happened but that may not + * be represented in the change bitfield. + * + * Also, even though we don't need to know the currently supported alt + * modes, we run the GET_CAM_SUPPORTED command to ensure the PPM does + * not get stuck in case it assumes we do. + * Always do this, rather than relying on UCSI_CONSTAT_CAM_CHANGE to be + * set in the change bitfield. + * + * We end up with the following actions: + * 1. UCSI_GET_CONNECTOR_STATUS, store result, update unprocessed_changes + * 2. UCSI_GET_CAM_SUPPORTED, discard result + * 3. ACK connector change + * 4. UCSI_GET_CONNECTOR_STATUS, store result + * 5. Infere lost changes by comparing UCSI_GET_CONNECTOR_STATUS results + * 6. If PPM reported a new change, then restart in order to ACK + * 7. Process everything as usual. + * + * We may end up seeing a change twice, but we can only miss extremely + * short transitional changes. + */ + + /* 1. First UCSI_GET_CONNECTOR_STATUS */ command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num); - ret = ucsi_send_command(ucsi, command, &con->status, - sizeof(con->status)); + ret = ucsi_send_command(ucsi, command, &pre_ack_status, + sizeof(pre_ack_status)); if (ret < 0) { dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n", __func__, ret); goto out_unlock; } + con->unprocessed_changes |= pre_ack_status.change; + + /* 2. Run UCSI_GET_CAM_SUPPORTED and discard the result. */ + command = UCSI_GET_CAM_SUPPORTED; + command |= UCSI_CONNECTOR_NUMBER(con->num); + ucsi_send_command(con->ucsi, command, NULL, 0); + + /* 3. ACK connector change */ + clear_bit(EVENT_PENDING, &ucsi->flags); + ret = ucsi_acknowledge_connector_change(ucsi); + if (ret) { + dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret); + goto out_unlock; + } + + /* 4. Second UCSI_GET_CONNECTOR_STATUS */ + command = UCSI_GET_CONNECTOR_STATUS | UCSI_CONNECTOR_NUMBER(con->num); + ret = ucsi_send_command(ucsi, command, &post_ack_status, + sizeof(post_ack_status)); + if (ret < 0) { + dev_err(ucsi->dev, "%s: GET_CONNECTOR_STATUS failed (%d)\n", + __func__, ret); + goto out_unlock; + } + + /* 5. Inferre any missing changes */ + changed_flags = pre_ack_status.flags ^ post_ack_status.flags; + inferred_changes = 0; + if (UCSI_CONSTAT_PWR_OPMODE(changed_flags) != 0) + inferred_changes |= UCSI_CONSTAT_POWER_OPMODE_CHANGE; + + if (changed_flags & UCSI_CONSTAT_CONNECTED) + inferred_changes |= UCSI_CONSTAT_CONNECT_CHANGE; + + if (changed_flags & UCSI_CONSTAT_PWR_DIR) + inferred_changes |= UCSI_CONSTAT_POWER_DIR_CHANGE; + + if (UCSI_CONSTAT_PARTNER_FLAGS(changed_flags) != 0) + inferred_changes |= UCSI_CONSTAT_PARTNER_CHANGE; + + if (UCSI_CONSTAT_PARTNER_TYPE(changed_flags) != 0) + inferred_changes |= UCSI_CONSTAT_PARTNER_CHANGE; + + /* Mask out anything that was correctly notified in the later call. */ + inferred_changes &= ~post_ack_status.change; + if (inferred_changes) + dev_dbg(ucsi->dev, "%s: Inferred changes that would have been lost: 0x%04x\n", + __func__, inferred_changes); + + con->unprocessed_changes |= inferred_changes; + + /* 6. If PPM reported a new change, then restart in order to ACK */ + if (post_ack_status.change) + goto out_unlock; + + /* 7. Continue as if nothing happened */ + con->status = post_ack_status; + con->status.change = con->unprocessed_changes; + con->unprocessed_changes = 0; role = !!(con->status.flags & UCSI_CONSTAT_PWR_DIR); @@ -703,28 +795,19 @@ static void ucsi_handle_connector_change(struct work_struct *work) ucsi_port_psy_changed(con); } - if (con->status.change & UCSI_CONSTAT_CAM_CHANGE) { - /* - * We don't need to know the currently supported alt modes here. - * Running GET_CAM_SUPPORTED command just to make sure the PPM - * does not get stuck in case it assumes we do so. - */ - command = UCSI_GET_CAM_SUPPORTED; - command |= UCSI_CONNECTOR_NUMBER(con->num); - ucsi_send_command(con->ucsi, command, NULL, 0); - } - if (con->status.change & UCSI_CONSTAT_PARTNER_CHANGE) ucsi_partner_change(con); - ret = ucsi_acknowledge_connector_change(ucsi); - if (ret) - dev_err(ucsi->dev, "%s: ACK failed (%d)", __func__, ret); - trace_ucsi_connector_change(con->num, &con->status); out_unlock: - clear_bit(EVENT_PENDING, &ucsi->flags); + if (test_and_clear_bit(EVENT_PENDING, &ucsi->flags)) { + schedule_work(&con->work); + mutex_unlock(&con->lock); + return; + } + + clear_bit(EVENT_PROCESSING, &ucsi->flags); mutex_unlock(&con->lock); } @@ -742,7 +825,9 @@ void ucsi_connector_change(struct ucsi *ucsi, u8 num) return; } - if (!test_and_set_bit(EVENT_PENDING, &ucsi->flags)) + set_bit(EVENT_PENDING, &ucsi->flags); + + if (!test_and_set_bit(EVENT_PROCESSING, &ucsi->flags)) schedule_work(&con->work); } EXPORT_SYMBOL_GPL(ucsi_connector_change); diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h index 047e17c4b492..fce23ad16c6d 100644 --- a/drivers/usb/typec/ucsi/ucsi.h +++ b/drivers/usb/typec/ucsi/ucsi.h @@ -299,6 +299,7 @@ struct ucsi { #define EVENT_PENDING 0 #define COMMAND_PENDING 1 #define ACK_PENDING 2 +#define EVENT_PROCESSING 3 }; #define UCSI_MAX_SVID 5 @@ -324,6 +325,7 @@ struct ucsi_connector { struct typec_capability typec_cap; + u16 unprocessed_changes; struct ucsi_connector_status status; struct ucsi_connector_capability cap; struct power_supply *psy;