linux-stable/include/linux/usb/tcpm.h
Badhri Jagan Sridharan 599f008c25 usb: typec: tcpm: Add callbacks to mitigate wakeups due to contaminant
On some of the TCPC implementations, when the Type-C port is exposed
to contaminants, such as water, TCPC stops toggling while reporting OPEN
either by the time TCPM reads CC pin status or during CC debounce
window. This causes TCPM to be stuck in TOGGLING state. If TCPM is made
to restart toggling, the behavior recurs causing redundant CPU wakeups
till the USB-C port is free of contaminant.

[206199.287817] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[206199.640337] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[206199.985789] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]

(or)

[ 7853.867577] Start toggling
[ 7853.889921] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[ 7855.698765] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected]
[ 7855.698790] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS]
[ 7855.698826] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS]
[ 7855.703559] CC1: 0 -> 0, CC2: 5 -> 5 [state SNK_ATTACH_WAIT, polarity 0, connected]
[ 7855.856555] CC1: 0 -> 0, CC2: 5 -> 0 [state SNK_ATTACH_WAIT, polarity 0, disconnected]
[ 7855.856581] state change SNK_ATTACH_WAIT -> SNK_ATTACH_WAIT [rev3 NONE_AMS]
[ 7855.856613] pending state change SNK_ATTACH_WAIT -> SNK_UNATTACHED @ 170 ms [rev3 NONE_AMS]
[ 7856.027744] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [delayed 170 ms]
[ 7856.181949] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[ 7856.187896] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[ 7857.645630] CC1: 0 -> 0, CC2: 0 -> 0 [state TOGGLING, polarity 0, disconnected]
[ 7857.647291] CC1: 0 -> 0, CC2: 0 -> 5 [state TOGGLING, polarity 0, connected]
[ 7857.647298] state change TOGGLING -> SNK_ATTACH_WAIT [rev3 NONE_AMS]
[ 7857.647310] pending state change SNK_ATTACH_WAIT -> SNK_DEBOUNCED @ 170 ms [rev3 NONE_AMS]
[ 7857.808106] CC1: 0 -> 0, CC2: 5 -> 0 [state SNK_ATTACH_WAIT, polarity 0, disconnected]
[ 7857.808123] state change SNK_ATTACH_WAIT -> SNK_ATTACH_WAIT [rev3 NONE_AMS]
[ 7857.808150] pending state change SNK_ATTACH_WAIT -> SNK_UNATTACHED @ 170 ms [rev3 NONE_AMS]
[ 7857.978727] state change SNK_ATTACH_WAIT -> SNK_UNATTACHED [delayed 170 ms]

To mitigate redundant TCPM wakeups, TCPCs which do have the needed hardware
can implement the check_contaminant callback which is invoked by TCPM
to evaluate for presence of contaminant. Lower level TCPC driver can
restart toggling through TCPM_PORT_CLEAN event when the driver detects
that USB-C port is free of contaminant. check_contaminant callback also
passes the disconnect_while_debounce flag which when true denotes that
the CC pins transitioned to OPEN state during the CC debounce window.

Signed-off-by: Badhri Jagan Sridharan <badhri@google.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20230114093246.1933321-1-badhri@google.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-17 17:29:23 +01:00

177 lines
6.8 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright 2015-2017 Google, Inc
*/
#ifndef __LINUX_USB_TCPM_H
#define __LINUX_USB_TCPM_H
#include <linux/bitops.h>
#include <linux/usb/typec.h>
#include "pd.h"
enum typec_cc_status {
TYPEC_CC_OPEN,
TYPEC_CC_RA,
TYPEC_CC_RD,
TYPEC_CC_RP_DEF,
TYPEC_CC_RP_1_5,
TYPEC_CC_RP_3_0,
};
/* Collision Avoidance */
#define SINK_TX_NG TYPEC_CC_RP_1_5
#define SINK_TX_OK TYPEC_CC_RP_3_0
enum typec_cc_polarity {
TYPEC_POLARITY_CC1,
TYPEC_POLARITY_CC2,
};
/* Time to wait for TCPC to complete transmit */
#define PD_T_TCPC_TX_TIMEOUT 100 /* in ms */
#define PD_ROLE_SWAP_TIMEOUT (MSEC_PER_SEC * 10)
#define PD_PPS_CTRL_TIMEOUT (MSEC_PER_SEC * 10)
enum tcpm_transmit_status {
TCPC_TX_SUCCESS = 0,
TCPC_TX_DISCARDED = 1,
TCPC_TX_FAILED = 2,
};
enum tcpm_transmit_type {
TCPC_TX_SOP = 0,
TCPC_TX_SOP_PRIME = 1,
TCPC_TX_SOP_PRIME_PRIME = 2,
TCPC_TX_SOP_DEBUG_PRIME = 3,
TCPC_TX_SOP_DEBUG_PRIME_PRIME = 4,
TCPC_TX_HARD_RESET = 5,
TCPC_TX_CABLE_RESET = 6,
TCPC_TX_BIST_MODE_2 = 7
};
/* Mux state attributes */
#define TCPC_MUX_USB_ENABLED BIT(0) /* USB enabled */
#define TCPC_MUX_DP_ENABLED BIT(1) /* DP enabled */
#define TCPC_MUX_POLARITY_INVERTED BIT(2) /* Polarity inverted */
/**
* struct tcpc_dev - Port configuration and callback functions
* @fwnode: Pointer to port fwnode
* @get_vbus: Called to read current VBUS state
* @get_current_limit:
* Optional; called by the tcpm core when configured as a snk
* and cc=Rp-def. This allows the tcpm to provide a fallback
* current-limit detection method for the cc=Rp-def case.
* For example, some tcpcs may include BC1.2 charger detection
* and use that in this case.
* @set_cc: Called to set value of CC pins
* @apply_rc: Optional; Needed to move TCPCI based chipset to APPLY_RC state
* as stated by the TCPCI specification.
* @get_cc: Called to read current CC pin values
* @set_polarity:
* Called to set polarity
* @set_vconn: Called to enable or disable VCONN
* @set_vbus: Called to enable or disable VBUS
* @set_current_limit:
* Optional; called to set current limit as negotiated
* with partner.
* @set_pd_rx: Called to enable or disable reception of PD messages
* @set_roles: Called to set power and data roles
* @start_toggling:
* Optional; if supported by hardware, called to start dual-role
* toggling or single-role connection detection. Toggling stops
* automatically if a connection is established.
* @try_role: Optional; called to set a preferred role
* @pd_transmit:Called to transmit PD message
* @set_bist_data: Turn on/off bist data mode for compliance testing
* @enable_frs:
* Optional; Called to enable/disable PD 3.0 fast role swap.
* Enabling frs is accessory dependent as not all PD3.0
* accessories support fast role swap.
* @frs_sourcing_vbus:
* Optional; Called to notify that vbus is now being sourced.
* Low level drivers can perform chip specific operations, if any.
* @enable_auto_vbus_discharge:
* Optional; TCPCI spec based TCPC implementations can optionally
* support hardware to autonomously dischrge vbus upon disconnecting
* as sink or source. TCPM signals TCPC to enable the mechanism upon
* entering connected state and signals disabling upon disconnect.
* @set_auto_vbus_discharge_threshold:
* Mandatory when enable_auto_vbus_discharge is implemented. TCPM
* calls this function to allow lower levels drivers to program the
* vbus threshold voltage below which the vbus discharge circuit
* will be turned on. requested_vbus_voltage is set to 0 when vbus
* is going to disappear knowingly i.e. during PR_SWAP and
* HARD_RESET etc.
* @is_vbus_vsafe0v:
* Optional; TCPCI spec based TCPC implementations are expected to
* detect VSAFE0V voltage level at vbus. When detection of VSAFE0V
* is supported by TCPC, set this callback for TCPM to query
* whether vbus is at VSAFE0V when needed.
* Returns true when vbus is at VSAFE0V, false otherwise.
* @set_partner_usb_comm_capable:
* Optional; The USB Communications Capable bit indicates if port
* partner is capable of communication over the USB data lines
* (e.g. D+/- or SS Tx/Rx). Called to notify the status of the bit.
* @check_contaminant:
* Optional; The callback is called when CC pins report open status
* at the end of the deboumce period or when the port is still
* toggling. Chip level drivers are expected to check for contaminant
* and call tcpm_clean_port when the port is clean.
*/
struct tcpc_dev {
struct fwnode_handle *fwnode;
int (*init)(struct tcpc_dev *dev);
int (*get_vbus)(struct tcpc_dev *dev);
int (*get_current_limit)(struct tcpc_dev *dev);
int (*set_cc)(struct tcpc_dev *dev, enum typec_cc_status cc);
int (*apply_rc)(struct tcpc_dev *dev, enum typec_cc_status cc,
enum typec_cc_polarity polarity);
int (*get_cc)(struct tcpc_dev *dev, enum typec_cc_status *cc1,
enum typec_cc_status *cc2);
int (*set_polarity)(struct tcpc_dev *dev,
enum typec_cc_polarity polarity);
int (*set_vconn)(struct tcpc_dev *dev, bool on);
int (*set_vbus)(struct tcpc_dev *dev, bool on, bool charge);
int (*set_current_limit)(struct tcpc_dev *dev, u32 max_ma, u32 mv);
int (*set_pd_rx)(struct tcpc_dev *dev, bool on);
int (*set_roles)(struct tcpc_dev *dev, bool attached,
enum typec_role role, enum typec_data_role data);
int (*start_toggling)(struct tcpc_dev *dev,
enum typec_port_type port_type,
enum typec_cc_status cc);
int (*try_role)(struct tcpc_dev *dev, int role);
int (*pd_transmit)(struct tcpc_dev *dev, enum tcpm_transmit_type type,
const struct pd_message *msg, unsigned int negotiated_rev);
int (*set_bist_data)(struct tcpc_dev *dev, bool on);
int (*enable_frs)(struct tcpc_dev *dev, bool enable);
void (*frs_sourcing_vbus)(struct tcpc_dev *dev);
int (*enable_auto_vbus_discharge)(struct tcpc_dev *dev, bool enable);
int (*set_auto_vbus_discharge_threshold)(struct tcpc_dev *dev, enum typec_pwr_opmode mode,
bool pps_active, u32 requested_vbus_voltage);
bool (*is_vbus_vsafe0v)(struct tcpc_dev *dev);
void (*set_partner_usb_comm_capable)(struct tcpc_dev *dev, bool enable);
void (*check_contaminant)(struct tcpc_dev *dev);
};
struct tcpm_port;
struct tcpm_port *tcpm_register_port(struct device *dev, struct tcpc_dev *tcpc);
void tcpm_unregister_port(struct tcpm_port *port);
void tcpm_vbus_change(struct tcpm_port *port);
void tcpm_cc_change(struct tcpm_port *port);
void tcpm_sink_frs(struct tcpm_port *port);
void tcpm_sourcing_vbus(struct tcpm_port *port);
void tcpm_pd_receive(struct tcpm_port *port,
const struct pd_message *msg);
void tcpm_pd_transmit_complete(struct tcpm_port *port,
enum tcpm_transmit_status status);
void tcpm_pd_hard_reset(struct tcpm_port *port);
void tcpm_tcpc_reset(struct tcpm_port *port);
void tcpm_port_clean(struct tcpm_port *port);
bool tcpm_port_is_toggling(struct tcpm_port *port);
#endif /* __LINUX_USB_TCPM_H */