2018-09-28 23:47:31

by Badhri Jagan Sridharan

[permalink] [raw]
Subject: [PATCH 1/3] [PATCH 1/3] dt-bindings: connector: Add self-powered property

From USB_PD_R3_0
7.1.5 Response to Hard Resets
Device operation during and after a Hard Reset is defined as follows:
Self-powered devices Should Not disconnect from USB during a Hard Reset
(see Section 9.1.2).
Bus powered devices will disconnect from USB during a Hard Reset due to the
loss of their power source.

Therefore it is necessary to know whether the port belongs to
a device which is self powered or bus powered. This change
adds "self-powered" flag to the connector class which present indicates
that the port belongs to a device that is self powered. Else it is
bus powered usb device.

Signed-off-by: Badhri Jagan Sridharan <[email protected]>
---
Documentation/devicetree/bindings/connector/usb-connector.txt | 2 ++
1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/connector/usb-connector.txt b/Documentation/devicetree/bindings/connector/usb-connector.txt
index 8855bfcfd7785..8f7a36ae29bf7 100644
--- a/Documentation/devicetree/bindings/connector/usb-connector.txt
+++ b/Documentation/devicetree/bindings/connector/usb-connector.txt
@@ -14,6 +14,8 @@ Optional properties:
- label: symbolic name for the connector,
- type: size of the connector, should be specified in case of USB-A, USB-B
non-fullsize connectors: "mini", "micro".
+- self-powered: Set this property if the usb device that has its own power
+ source.

Optional properties for usb-c-connector:
- power-role: should be one of "source", "sink" or "dual"(DRP) if typec
--
2.19.0.605.g01d371f741-goog



2018-09-28 23:47:44

by Badhri Jagan Sridharan

[permalink] [raw]
Subject: [PATCH 2/3] [PATCH v2 2/3] usb: typec: tcpm: Do not disconnect link for self powered devices

During HARD_RESET the data link is disconnected.
For self powered device, the spec is advising against doing that.

From USB_PD_R3_0
7.1.5 Response to Hard Resets
Device operation during and after a Hard Reset is defined as follows:
Self-powered devices Should Not disconnect from USB during a Hard Reset
(see Section 9.1.2).
Bus powered devices will disconnect from USB during a Hard Reset due to the
loss of their power source.

Tackle this by letting TCPM know whether the device is self or bus powered.

This overcomes unnecessary port disconnections from hard reset.
Also, speeds up the enumeration time when connected to Type-A ports.

Signed-off-by: Badhri Jagan Sridharan <[email protected]>
---------
Version history:

V2:
Based on feedback from [email protected]
- self_powered added to the struct tcpm_port which is populated from
a. "connector" node of the device tree in tcpm_fw_get_caps()
b. "self_powered" node of the tcpc_config in tcpm_copy_caps

Based on feedbase from [email protected]
- Code was refactored
- SRC_HARD_RESET_VBUS_OFF sets the link state to false based
on self_powered flag

V1 located here:
https://lkml.org/lkml/2018/9/13/94
---
drivers/usb/typec/tcpm.c | 12 ++++++++++--
include/linux/usb/tcpm.h | 1 +
2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
index 4f1f4215f3d6e..c3ac0e46106b4 100644
--- a/drivers/usb/typec/tcpm.c
+++ b/drivers/usb/typec/tcpm.c
@@ -317,6 +317,9 @@ struct tcpm_port {
/* Deadline in jiffies to exit src_try_wait state */
unsigned long max_wait;

+ /* port belongs to a self powered device */
+ bool self_powered;
+
#ifdef CONFIG_DEBUG_FS
struct dentry *dentry;
struct mutex logbuffer_lock; /* log buffer access lock */
@@ -3257,7 +3260,8 @@ static void run_state_machine(struct tcpm_port *port)
case SRC_HARD_RESET_VBUS_OFF:
tcpm_set_vconn(port, true);
tcpm_set_vbus(port, false);
- tcpm_set_roles(port, false, TYPEC_SOURCE, TYPEC_HOST);
+ tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE,
+ TYPEC_HOST);
tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER);
break;
case SRC_HARD_RESET_VBUS_ON:
@@ -3270,7 +3274,8 @@ static void run_state_machine(struct tcpm_port *port)
memset(&port->pps_data, 0, sizeof(port->pps_data));
tcpm_set_vconn(port, false);
tcpm_set_charge(port, false);
- tcpm_set_roles(port, false, TYPEC_SINK, TYPEC_DEVICE);
+ tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
+ TYPEC_DEVICE);
/*
* VBUS may or may not toggle, depending on the adapter.
* If it doesn't toggle, transition to SNK_HARD_RESET_SINK_ON
@@ -4409,6 +4414,8 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
return -EINVAL;
port->operating_snk_mw = mw / 1000;

+ port->self_powered = fwnode_property_read_bool(fwnode, "self-powered");
+
return 0;
}

@@ -4717,6 +4724,7 @@ static int tcpm_copy_caps(struct tcpm_port *port,
port->typec_caps.prefer_role = tcfg->default_role;
port->typec_caps.type = tcfg->type;
port->typec_caps.data = tcfg->data;
+ port->self_powered = port->tcpc->config->self_powered;

return 0;
}
diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
index 7e7fbfb84e8e3..50c74a77db55c 100644
--- a/include/linux/usb/tcpm.h
+++ b/include/linux/usb/tcpm.h
@@ -89,6 +89,7 @@ struct tcpc_config {
enum typec_port_data data;
enum typec_role default_role;
bool try_role_hw; /* try.{src,snk} implemented in hardware */
+ bool self_powered; /* port belongs to a self powered device */

const struct typec_altmode_desc *alt_modes;
};
--
2.19.0.605.g01d371f741-goog


2018-09-28 23:49:24

by Badhri Jagan Sridharan

[permalink] [raw]
Subject: [PATCH 3/3] [PATCH v2 3/3] usb: typec: tcpm: charge current handling for sink during hard reset

During the initial connect to a non-pd port, sink would hard reset
twice before deeming that the port partner is non-pd. TCPM sets the
the charge path to false during the hard reset. This causes unnecessary
connects/disconnects of charge path and makes port take longer to
charge from the non-pd ports. Avoid this by not setting the charge path
to false unless the partner has already identified to be pd capable.

When partner is a pd port, set the charge path to false in
SNK_HARD_RESET_SINK_OFF. Set the current limits to default value based
of CC pull up and resume the charge path when port enters
SNK_HARD_RESET_SINK_ON.

Signed-off-by: Badhri Jagan Sridharan <[email protected]>

--------
Changes in V2:
Based on feedback of [email protected]
- vsafe_5v_hard_reset flag from tcpc_config is removed
- Patch only differentiates between pd port partner and non-pd port
partner

V1 version of the patch is here:
https://lkml.org/lkml/2018/9/14/11
---
drivers/usb/typec/tcpm.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
index c3ac0e46106b4..c25a69922ee6a 100644
--- a/drivers/usb/typec/tcpm.c
+++ b/drivers/usb/typec/tcpm.c
@@ -3273,7 +3273,8 @@ static void run_state_machine(struct tcpm_port *port)
case SNK_HARD_RESET_SINK_OFF:
memset(&port->pps_data, 0, sizeof(port->pps_data));
tcpm_set_vconn(port, false);
- tcpm_set_charge(port, false);
+ if (port->pd_capable)
+ tcpm_set_charge(port, false);
tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
TYPEC_DEVICE);
/*
@@ -3305,6 +3306,12 @@ static void run_state_machine(struct tcpm_port *port)
* Similar, dual-mode ports in source mode should transition
* to PE_SNK_Transition_to_default.
*/
+ if (port->pd_capable) {
+ tcpm_set_current_limit(port,
+ tcpm_get_current_limit(port),
+ 5000);
+ tcpm_set_charge(port, true);
+ }
tcpm_set_attached_state(port, true);
tcpm_set_state(port, SNK_STARTUP, 0);
break;
--
2.19.0.605.g01d371f741-goog


2018-09-28 23:49:49

by Badhri Jagan Sridharan

[permalink] [raw]
Subject: Re: [PATCH 3/3] [PATCH v2 3/3] usb: typec: tcpm: charge current handling for sink during hard reset

+ [email protected]
On Fri, Sep 28, 2018 at 4:47 PM Badhri Jagan Sridharan
<[email protected]> wrote:
>
> During the initial connect to a non-pd port, sink would hard reset
> twice before deeming that the port partner is non-pd. TCPM sets the
> the charge path to false during the hard reset. This causes unnecessary
> connects/disconnects of charge path and makes port take longer to
> charge from the non-pd ports. Avoid this by not setting the charge path
> to false unless the partner has already identified to be pd capable.
>
> When partner is a pd port, set the charge path to false in
> SNK_HARD_RESET_SINK_OFF. Set the current limits to default value based
> of CC pull up and resume the charge path when port enters
> SNK_HARD_RESET_SINK_ON.
>
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>
>
> --------
> Changes in V2:
> Based on feedback of [email protected]
> - vsafe_5v_hard_reset flag from tcpc_config is removed
> - Patch only differentiates between pd port partner and non-pd port
> partner
>
> V1 version of the patch is here:
> https://lkml.org/lkml/2018/9/14/11
> ---
> drivers/usb/typec/tcpm.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index c3ac0e46106b4..c25a69922ee6a 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -3273,7 +3273,8 @@ static void run_state_machine(struct tcpm_port *port)
> case SNK_HARD_RESET_SINK_OFF:
> memset(&port->pps_data, 0, sizeof(port->pps_data));
> tcpm_set_vconn(port, false);
> - tcpm_set_charge(port, false);
> + if (port->pd_capable)
> + tcpm_set_charge(port, false);
> tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
> TYPEC_DEVICE);
> /*
> @@ -3305,6 +3306,12 @@ static void run_state_machine(struct tcpm_port *port)
> * Similar, dual-mode ports in source mode should transition
> * to PE_SNK_Transition_to_default.
> */
> + if (port->pd_capable) {
> + tcpm_set_current_limit(port,
> + tcpm_get_current_limit(port),
> + 5000);
> + tcpm_set_charge(port, true);
> + }
> tcpm_set_attached_state(port, true);
> tcpm_set_state(port, SNK_STARTUP, 0);
> break;
> --
> 2.19.0.605.g01d371f741-goog
>

2018-09-30 22:05:14

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH 2/3] [PATCH v2 2/3] usb: typec: tcpm: Do not disconnect link for self powered devices

On 09/28/2018 04:47 PM, Badhri Jagan Sridharan wrote:
> During HARD_RESET the data link is disconnected.
> For self powered device, the spec is advising against doing that.
>
>>From USB_PD_R3_0
> 7.1.5 Response to Hard Resets
> Device operation during and after a Hard Reset is defined as follows:
> Self-powered devices Should Not disconnect from USB during a Hard Reset
> (see Section 9.1.2).
> Bus powered devices will disconnect from USB during a Hard Reset due to the
> loss of their power source.
>
> Tackle this by letting TCPM know whether the device is self or bus powered.
>
> This overcomes unnecessary port disconnections from hard reset.
> Also, speeds up the enumeration time when connected to Type-A ports.
>
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>

Reviewed-by: Guenter Roeck <[email protected]>

> ---------
> Version history:
>
> V2:
> Based on feedback from [email protected]
> - self_powered added to the struct tcpm_port which is populated from
> a. "connector" node of the device tree in tcpm_fw_get_caps()
> b. "self_powered" node of the tcpc_config in tcpm_copy_caps
>
> Based on feedbase from [email protected]
> - Code was refactored
> - SRC_HARD_RESET_VBUS_OFF sets the link state to false based
> on self_powered flag
>
> V1 located here:
> https://lkml.org/lkml/2018/9/13/94
> ---
> drivers/usb/typec/tcpm.c | 12 ++++++++++--
> include/linux/usb/tcpm.h | 1 +
> 2 files changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index 4f1f4215f3d6e..c3ac0e46106b4 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -317,6 +317,9 @@ struct tcpm_port {
> /* Deadline in jiffies to exit src_try_wait state */
> unsigned long max_wait;
>
> + /* port belongs to a self powered device */
> + bool self_powered;
> +
> #ifdef CONFIG_DEBUG_FS
> struct dentry *dentry;
> struct mutex logbuffer_lock; /* log buffer access lock */
> @@ -3257,7 +3260,8 @@ static void run_state_machine(struct tcpm_port *port)
> case SRC_HARD_RESET_VBUS_OFF:
> tcpm_set_vconn(port, true);
> tcpm_set_vbus(port, false);
> - tcpm_set_roles(port, false, TYPEC_SOURCE, TYPEC_HOST);
> + tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE,
> + TYPEC_HOST);
> tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER);
> break;
> case SRC_HARD_RESET_VBUS_ON:
> @@ -3270,7 +3274,8 @@ static void run_state_machine(struct tcpm_port *port)
> memset(&port->pps_data, 0, sizeof(port->pps_data));
> tcpm_set_vconn(port, false);
> tcpm_set_charge(port, false);
> - tcpm_set_roles(port, false, TYPEC_SINK, TYPEC_DEVICE);
> + tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
> + TYPEC_DEVICE);
> /*
> * VBUS may or may not toggle, depending on the adapter.
> * If it doesn't toggle, transition to SNK_HARD_RESET_SINK_ON
> @@ -4409,6 +4414,8 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
> return -EINVAL;
> port->operating_snk_mw = mw / 1000;
>
> + port->self_powered = fwnode_property_read_bool(fwnode, "self-powered");
> +
> return 0;
> }
>
> @@ -4717,6 +4724,7 @@ static int tcpm_copy_caps(struct tcpm_port *port,
> port->typec_caps.prefer_role = tcfg->default_role;
> port->typec_caps.type = tcfg->type;
> port->typec_caps.data = tcfg->data;
> + port->self_powered = port->tcpc->config->self_powered;
>
> return 0;
> }
> diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
> index 7e7fbfb84e8e3..50c74a77db55c 100644
> --- a/include/linux/usb/tcpm.h
> +++ b/include/linux/usb/tcpm.h
> @@ -89,6 +89,7 @@ struct tcpc_config {
> enum typec_port_data data;
> enum typec_role default_role;
> bool try_role_hw; /* try.{src,snk} implemented in hardware */
> + bool self_powered; /* port belongs to a self powered device */
>
> const struct typec_altmode_desc *alt_modes;
> };
>


2018-09-30 22:07:07

by Guenter Roeck

[permalink] [raw]
Subject: Re: [PATCH 3/3] [PATCH v2 3/3] usb: typec: tcpm: charge current handling for sink during hard reset

On 09/28/2018 04:47 PM, Badhri Jagan Sridharan wrote:
> During the initial connect to a non-pd port, sink would hard reset
> twice before deeming that the port partner is non-pd. TCPM sets the
> the charge path to false during the hard reset. This causes unnecessary
> connects/disconnects of charge path and makes port take longer to
> charge from the non-pd ports. Avoid this by not setting the charge path
> to false unless the partner has already identified to be pd capable.
>
> When partner is a pd port, set the charge path to false in
> SNK_HARD_RESET_SINK_OFF. Set the current limits to default value based
> of CC pull up and resume the charge path when port enters
> SNK_HARD_RESET_SINK_ON.
>
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>

Reviewed-by: Guenter Roeck <[email protected]>

>
> --------
> Changes in V2:
> Based on feedback of [email protected]
> - vsafe_5v_hard_reset flag from tcpc_config is removed
> - Patch only differentiates between pd port partner and non-pd port
> partner
>
> V1 version of the patch is here:
> https://lkml.org/lkml/2018/9/14/11
> ---
> drivers/usb/typec/tcpm.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index c3ac0e46106b4..c25a69922ee6a 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -3273,7 +3273,8 @@ static void run_state_machine(struct tcpm_port *port)
> case SNK_HARD_RESET_SINK_OFF:
> memset(&port->pps_data, 0, sizeof(port->pps_data));
> tcpm_set_vconn(port, false);
> - tcpm_set_charge(port, false);
> + if (port->pd_capable)
> + tcpm_set_charge(port, false);
> tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
> TYPEC_DEVICE);
> /*
> @@ -3305,6 +3306,12 @@ static void run_state_machine(struct tcpm_port *port)
> * Similar, dual-mode ports in source mode should transition
> * to PE_SNK_Transition_to_default.
> */
> + if (port->pd_capable) {
> + tcpm_set_current_limit(port,
> + tcpm_get_current_limit(port),
> + 5000);
> + tcpm_set_charge(port, true);
> + }
> tcpm_set_attached_state(port, true);
> tcpm_set_state(port, SNK_STARTUP, 0);
> break;
>


2018-10-01 09:54:27

by Heikki Krogerus

[permalink] [raw]
Subject: Re: [PATCH 2/3] [PATCH v2 2/3] usb: typec: tcpm: Do not disconnect link for self powered devices

On Fri, Sep 28, 2018 at 04:47:02PM -0700, Badhri Jagan Sridharan wrote:
> During HARD_RESET the data link is disconnected.
> For self powered device, the spec is advising against doing that.
>
> >From USB_PD_R3_0
> 7.1.5 Response to Hard Resets
> Device operation during and after a Hard Reset is defined as follows:
> Self-powered devices Should Not disconnect from USB during a Hard Reset
> (see Section 9.1.2).
> Bus powered devices will disconnect from USB during a Hard Reset due to the
> loss of their power source.
>
> Tackle this by letting TCPM know whether the device is self or bus powered.
>
> This overcomes unnecessary port disconnections from hard reset.
> Also, speeds up the enumeration time when connected to Type-A ports.
>
> Signed-off-by: Badhri Jagan Sridharan <[email protected]>

Could you rebase these on top of the latest usb-next. These are not
going to apply cleanly on top of it because tcpm.c and all port
drivers are now in their own directory drivers/usb/typec/tcpm/.

Reviewed-by: Heikki Krogerus <[email protected]>

> ---------
> Version history:
>
> V2:
> Based on feedback from [email protected]
> - self_powered added to the struct tcpm_port which is populated from
> a. "connector" node of the device tree in tcpm_fw_get_caps()
> b. "self_powered" node of the tcpc_config in tcpm_copy_caps
>
> Based on feedbase from [email protected]
> - Code was refactored
> - SRC_HARD_RESET_VBUS_OFF sets the link state to false based
> on self_powered flag
>
> V1 located here:
> https://lkml.org/lkml/2018/9/13/94
> ---
> drivers/usb/typec/tcpm.c | 12 ++++++++++--
> include/linux/usb/tcpm.h | 1 +
> 2 files changed, 11 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> index 4f1f4215f3d6e..c3ac0e46106b4 100644
> --- a/drivers/usb/typec/tcpm.c
> +++ b/drivers/usb/typec/tcpm.c
> @@ -317,6 +317,9 @@ struct tcpm_port {
> /* Deadline in jiffies to exit src_try_wait state */
> unsigned long max_wait;
>
> + /* port belongs to a self powered device */
> + bool self_powered;
> +
> #ifdef CONFIG_DEBUG_FS
> struct dentry *dentry;
> struct mutex logbuffer_lock; /* log buffer access lock */
> @@ -3257,7 +3260,8 @@ static void run_state_machine(struct tcpm_port *port)
> case SRC_HARD_RESET_VBUS_OFF:
> tcpm_set_vconn(port, true);
> tcpm_set_vbus(port, false);
> - tcpm_set_roles(port, false, TYPEC_SOURCE, TYPEC_HOST);
> + tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE,
> + TYPEC_HOST);
> tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER);
> break;
> case SRC_HARD_RESET_VBUS_ON:
> @@ -3270,7 +3274,8 @@ static void run_state_machine(struct tcpm_port *port)
> memset(&port->pps_data, 0, sizeof(port->pps_data));
> tcpm_set_vconn(port, false);
> tcpm_set_charge(port, false);
> - tcpm_set_roles(port, false, TYPEC_SINK, TYPEC_DEVICE);
> + tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
> + TYPEC_DEVICE);
> /*
> * VBUS may or may not toggle, depending on the adapter.
> * If it doesn't toggle, transition to SNK_HARD_RESET_SINK_ON
> @@ -4409,6 +4414,8 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
> return -EINVAL;
> port->operating_snk_mw = mw / 1000;
>
> + port->self_powered = fwnode_property_read_bool(fwnode, "self-powered");
> +
> return 0;
> }
>
> @@ -4717,6 +4724,7 @@ static int tcpm_copy_caps(struct tcpm_port *port,
> port->typec_caps.prefer_role = tcfg->default_role;
> port->typec_caps.type = tcfg->type;
> port->typec_caps.data = tcfg->data;
> + port->self_powered = port->tcpc->config->self_powered;
>
> return 0;
> }
> diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
> index 7e7fbfb84e8e3..50c74a77db55c 100644
> --- a/include/linux/usb/tcpm.h
> +++ b/include/linux/usb/tcpm.h
> @@ -89,6 +89,7 @@ struct tcpc_config {
> enum typec_port_data data;
> enum typec_role default_role;
> bool try_role_hw; /* try.{src,snk} implemented in hardware */
> + bool self_powered; /* port belongs to a self powered device */
>
> const struct typec_altmode_desc *alt_modes;
> };

Thanks,

--
heikki

2018-10-01 19:47:14

by Badhri Jagan Sridharan

[permalink] [raw]
Subject: Re: [PATCH 2/3] [PATCH v2 2/3] usb: typec: tcpm: Do not disconnect link for self powered devices

Sure. Just resent the patch stack !
On Mon, Oct 1, 2018 at 2:54 AM Heikki Krogerus
<[email protected]> wrote:
>
> On Fri, Sep 28, 2018 at 04:47:02PM -0700, Badhri Jagan Sridharan wrote:
> > During HARD_RESET the data link is disconnected.
> > For self powered device, the spec is advising against doing that.
> >
> > >From USB_PD_R3_0
> > 7.1.5 Response to Hard Resets
> > Device operation during and after a Hard Reset is defined as follows:
> > Self-powered devices Should Not disconnect from USB during a Hard Reset
> > (see Section 9.1.2).
> > Bus powered devices will disconnect from USB during a Hard Reset due to the
> > loss of their power source.
> >
> > Tackle this by letting TCPM know whether the device is self or bus powered.
> >
> > This overcomes unnecessary port disconnections from hard reset.
> > Also, speeds up the enumeration time when connected to Type-A ports.
> >
> > Signed-off-by: Badhri Jagan Sridharan <[email protected]>
>
> Could you rebase these on top of the latest usb-next. These are not
> going to apply cleanly on top of it because tcpm.c and all port
> drivers are now in their own directory drivers/usb/typec/tcpm/.
>
> Reviewed-by: Heikki Krogerus <[email protected]>
>
> > ---------
> > Version history:
> >
> > V2:
> > Based on feedback from [email protected]
> > - self_powered added to the struct tcpm_port which is populated from
> > a. "connector" node of the device tree in tcpm_fw_get_caps()
> > b. "self_powered" node of the tcpc_config in tcpm_copy_caps
> >
> > Based on feedbase from [email protected]
> > - Code was refactored
> > - SRC_HARD_RESET_VBUS_OFF sets the link state to false based
> > on self_powered flag
> >
> > V1 located here:
> > https://lkml.org/lkml/2018/9/13/94
> > ---
> > drivers/usb/typec/tcpm.c | 12 ++++++++++--
> > include/linux/usb/tcpm.h | 1 +
> > 2 files changed, 11 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
> > index 4f1f4215f3d6e..c3ac0e46106b4 100644
> > --- a/drivers/usb/typec/tcpm.c
> > +++ b/drivers/usb/typec/tcpm.c
> > @@ -317,6 +317,9 @@ struct tcpm_port {
> > /* Deadline in jiffies to exit src_try_wait state */
> > unsigned long max_wait;
> >
> > + /* port belongs to a self powered device */
> > + bool self_powered;
> > +
> > #ifdef CONFIG_DEBUG_FS
> > struct dentry *dentry;
> > struct mutex logbuffer_lock; /* log buffer access lock */
> > @@ -3257,7 +3260,8 @@ static void run_state_machine(struct tcpm_port *port)
> > case SRC_HARD_RESET_VBUS_OFF:
> > tcpm_set_vconn(port, true);
> > tcpm_set_vbus(port, false);
> > - tcpm_set_roles(port, false, TYPEC_SOURCE, TYPEC_HOST);
> > + tcpm_set_roles(port, port->self_powered, TYPEC_SOURCE,
> > + TYPEC_HOST);
> > tcpm_set_state(port, SRC_HARD_RESET_VBUS_ON, PD_T_SRC_RECOVER);
> > break;
> > case SRC_HARD_RESET_VBUS_ON:
> > @@ -3270,7 +3274,8 @@ static void run_state_machine(struct tcpm_port *port)
> > memset(&port->pps_data, 0, sizeof(port->pps_data));
> > tcpm_set_vconn(port, false);
> > tcpm_set_charge(port, false);
> > - tcpm_set_roles(port, false, TYPEC_SINK, TYPEC_DEVICE);
> > + tcpm_set_roles(port, port->self_powered, TYPEC_SINK,
> > + TYPEC_DEVICE);
> > /*
> > * VBUS may or may not toggle, depending on the adapter.
> > * If it doesn't toggle, transition to SNK_HARD_RESET_SINK_ON
> > @@ -4409,6 +4414,8 @@ static int tcpm_fw_get_caps(struct tcpm_port *port,
> > return -EINVAL;
> > port->operating_snk_mw = mw / 1000;
> >
> > + port->self_powered = fwnode_property_read_bool(fwnode, "self-powered");
> > +
> > return 0;
> > }
> >
> > @@ -4717,6 +4724,7 @@ static int tcpm_copy_caps(struct tcpm_port *port,
> > port->typec_caps.prefer_role = tcfg->default_role;
> > port->typec_caps.type = tcfg->type;
> > port->typec_caps.data = tcfg->data;
> > + port->self_powered = port->tcpc->config->self_powered;
> >
> > return 0;
> > }
> > diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
> > index 7e7fbfb84e8e3..50c74a77db55c 100644
> > --- a/include/linux/usb/tcpm.h
> > +++ b/include/linux/usb/tcpm.h
> > @@ -89,6 +89,7 @@ struct tcpc_config {
> > enum typec_port_data data;
> > enum typec_role default_role;
> > bool try_role_hw; /* try.{src,snk} implemented in hardware */
> > + bool self_powered; /* port belongs to a self powered device */
> >
> > const struct typec_altmode_desc *alt_modes;
> > };
>
> Thanks,
>
> --
> heikki