[PATCH 8/8] usb: typec: tcpm: Support for Alternate Modes

From: Heikki Krogerus
Date: Wed Jun 27 2018 - 11:20:42 EST

This adds more complete handling of VDMs and registration of
partner alternate modes, and introduces callbacks for
alternate mode operations.

Only DFP role is supported for now.

Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
---
drivers/usb/typec/tcpm.c | 165 ++++++++++++++++++++++++++++++++-------
include/linux/usb/tcpm.h | 9 ---
2 files changed, 135 insertions(+), 39 deletions(-)

diff --git a/drivers/usb/typec/tcpm.c b/drivers/usb/typec/tcpm.c
index 026be4e1ec75..a15dfe35b0c8 100644
--- a/drivers/usb/typec/tcpm.c
+++ b/drivers/usb/typec/tcpm.c
@@ -26,7 +26,7 @@
#include <linux/usb/pd_vdo.h>
#include <linux/usb/role.h>
#include <linux/usb/tcpm.h>
-#include <linux/usb/typec.h>
+#include <linux/usb/typec_altmode.h>
#include <linux/workqueue.h>

#define FOREACH_STATE(S) \
@@ -169,13 +169,14 @@ enum pd_msg_request {
/* Alternate mode support */

#define SVID_DISCOVERY_MAX 16
+#define ALTMODE_DISCOVERY_MAX (SVID_DISCOVERY_MAX * MODE_DISCOVERY_MAX)

struct pd_mode_data {
int svid_index; /* current SVID index */
int nsvids;
u16 svids[SVID_DISCOVERY_MAX];
int altmodes; /* number of alternate modes */
- struct typec_altmode_desc altmode_desc[SVID_DISCOVERY_MAX];
+ struct typec_altmode_desc altmode_desc[ALTMODE_DISCOVERY_MAX];
};

struct pd_pps_data {
@@ -310,8 +311,8 @@ struct tcpm_port {

/* Alternate mode data */
struct pd_mode_data mode_data;
- struct typec_altmode *partner_altmode[SVID_DISCOVERY_MAX * 6];
- struct typec_altmode *port_altmode[SVID_DISCOVERY_MAX * 6];
+ struct typec_altmode *partner_altmode[ALTMODE_DISCOVERY_MAX];
+ struct typec_altmode *port_altmode[ALTMODE_DISCOVERY_MAX];

/* Deadline in jiffies to exit src_try_wait state */
unsigned long max_wait;
@@ -641,14 +642,14 @@ void tcpm_pd_transmit_complete(struct tcpm_port *port,
}
EXPORT_SYMBOL_GPL(tcpm_pd_transmit_complete);

-static int tcpm_mux_set(struct tcpm_port *port, enum tcpc_mux_mode mode,
+static int tcpm_mux_set(struct tcpm_port *port, int state,
enum usb_role usb_role,
enum typec_orientation orientation)
{
int ret;

- tcpm_log(port, "Requesting mux mode %d, usb-role %d, orientation %d",
- mode, usb_role, orientation);
+ tcpm_log(port, "Requesting mux state %d, usb-role %d, orientation %d",
+ state, usb_role, orientation);

ret = typec_set_orientation(port->typec_port, orientation);
if (ret)
@@ -660,7 +661,7 @@ static int tcpm_mux_set(struct tcpm_port *port, enum tcpc_mux_mode mode,
return ret;
}

- return typec_set_mode(port->typec_port, mode);
+ return typec_set_mode(port->typec_port, state);
}

static int tcpm_set_polarity(struct tcpm_port *port,
@@ -787,7 +788,7 @@ static int tcpm_set_roles(struct tcpm_port *port, bool attached,
else
usb_role = USB_ROLE_DEVICE;

- ret = tcpm_mux_set(port, TYPEC_MUX_USB, usb_role, orientation);
+ ret = tcpm_mux_set(port, TYPEC_STATE_USB, usb_role, orientation);
if (ret < 0)
return ret;

@@ -1014,36 +1015,57 @@ static void svdm_consume_modes(struct tcpm_port *port, const __le32 *payload,
pmdata->altmodes, paltmode->svid,
paltmode->mode, paltmode->vdo);

- port->partner_altmode[pmdata->altmodes] =
- typec_partner_register_altmode(port->partner, paltmode);
- if (!port->partner_altmode[pmdata->altmodes]) {
- tcpm_log(port,
- "Failed to register modes for SVID 0x%04x",
- paltmode->svid);
- return;
- }
pmdata->altmodes++;
}
}

+static void tcpm_register_partner_altmodes(struct tcpm_port *port)
+{
+ struct pd_mode_data *modep = &port->mode_data;
+ struct typec_altmode *altmode;
+ int i;
+
+ for (i = 0; i < modep->altmodes; i++) {
+ altmode = typec_partner_register_altmode(port->partner,
+ &modep->altmode_desc[i]);
+ if (!altmode)
+ tcpm_log(port, "Failed to register partner SVID 0x%04x",
+ modep->altmode_desc[i].svid);
+ port->partner_altmode[i] = altmode;
+ }
+}
+
#define supports_modal(port) PD_IDH_MODAL_SUPP((port)->partner_ident.id_header)

static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt,
u32 *response)
{
- u32 p0 = le32_to_cpu(payload[0]);
- int cmd_type = PD_VDO_CMDT(p0);
- int cmd = PD_VDO_CMD(p0);
+ struct typec_altmode *adev;
+ struct typec_altmode *pdev;
struct pd_mode_data *modep;
+ u32 p[PD_MAX_PAYLOAD];
int rlen = 0;
- u16 svid;
+ int cmd_type;
+ int cmd;
int i;

+ for (i = 0; i < cnt; i++)
+ p[i] = le32_to_cpu(payload[i]);
+
+ cmd_type = PD_VDO_CMDT(p[0]);
+ cmd = PD_VDO_CMD(p[0]);
+
tcpm_log(port, "Rx VDM cmd 0x%x type %d cmd %d len %d",
- p0, cmd_type, cmd, cnt);
+ p[0], cmd_type, cmd, cnt);

modep = &port->mode_data;

+ adev = typec_match_altmode(port->port_altmode, ALTMODE_DISCOVERY_MAX,
+ PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
+
+ pdev = typec_match_altmode(port->partner_altmode, ALTMODE_DISCOVERY_MAX,
+ PD_VDO_VID(p[0]), PD_VDO_OPOS(p[0]));
+
switch (cmd_type) {
case CMDT_INIT:
switch (cmd) {
@@ -1065,17 +1087,19 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt,
case CMD_EXIT_MODE:
break;
case CMD_ATTENTION:
- break;
+ /* Attention command does not have response */
+ typec_altmode_attention(adev, p[1]);
+ return 0;
default:
break;
}
if (rlen >= 1) {
- response[0] = p0 | VDO_CMDT(CMDT_RSP_ACK);
+ response[0] = p[0] | VDO_CMDT(CMDT_RSP_ACK);
} else if (rlen == 0) {
- response[0] = p0 | VDO_CMDT(CMDT_RSP_NAK);
+ response[0] = p[0] | VDO_CMDT(CMDT_RSP_NAK);
rlen = 1;
} else {
- response[0] = p0 | VDO_CMDT(CMDT_RSP_BUSY);
+ response[0] = p[0] | VDO_CMDT(CMDT_RSP_BUSY);
rlen = 1;
}
break;
@@ -1108,14 +1132,39 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt,
svdm_consume_modes(port, payload, cnt);
modep->svid_index++;
if (modep->svid_index < modep->nsvids) {
- svid = modep->svids[modep->svid_index];
+ u16 svid = modep->svids[modep->svid_index];
response[0] = VDO(svid, 1, CMD_DISCOVER_MODES);
rlen = 1;
} else {
- /* enter alternate mode if/when implemented */
+ tcpm_register_partner_altmodes(port);
}
break;
case CMD_ENTER_MODE:
+ typec_altmode_update_active(pdev, true);
+
+ if (typec_altmode_vdm(adev, p[0], &p[1], cnt)) {
+ response[0] = VDO(adev->svid, 1, CMD_EXIT_MODE);
+ response[0] |= VDO_OPOS(adev->mode);
+ return 1;
+ }
+ return 0;
+ case CMD_EXIT_MODE:
+ typec_altmode_update_active(pdev, false);
+
+ /* Back to USB Operation */
+ WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB,
+ NULL));
+ break;
+ default:
+ break;
+ }
+ break;
+ case CMDT_RSP_NAK:
+ switch (cmd) {
+ case CMD_ENTER_MODE:
+ /* Back to USB Operation */
+ WARN_ON(typec_altmode_notify(adev, TYPEC_STATE_USB,
+ NULL));
break;
default:
break;
@@ -1125,6 +1174,9 @@ static int tcpm_pd_svdm(struct tcpm_port *port, const __le32 *payload, int cnt,
break;
}

+ /* Informing the alternate mode drivers about everything */
+ typec_altmode_vdm(adev, p[0], &p[1], cnt);
+
return rlen;
}

@@ -1408,6 +1460,57 @@ static int tcpm_validate_caps(struct tcpm_port *port, const u32 *pdo,
return 0;
}

+static int tcpm_altmode_enter(struct typec_altmode *altmode)
+{
+ struct tcpm_port *port = typec_altmode_get_drvdata(altmode);
+ u32 header;
+
+ mutex_lock(&port->lock);
+ header = VDO(altmode->svid, 1, CMD_ENTER_MODE);
+ header |= VDO_OPOS(altmode->mode);
+
+ tcpm_queue_vdm(port, header, NULL, 0);
+ mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
+ mutex_unlock(&port->lock);
+
+ return 0;
+}
+
+static int tcpm_altmode_exit(struct typec_altmode *altmode)
+{
+ struct tcpm_port *port = typec_altmode_get_drvdata(altmode);
+ u32 header;
+
+ mutex_lock(&port->lock);
+ header = VDO(altmode->svid, 1, CMD_EXIT_MODE);
+ header |= VDO_OPOS(altmode->mode);
+
+ tcpm_queue_vdm(port, header, NULL, 0);
+ mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
+ mutex_unlock(&port->lock);
+
+ return 0;
+}
+
+static int tcpm_altmode_vdm(struct typec_altmode *altmode,
+ u32 header, const u32 *data, int count)
+{
+ struct tcpm_port *port = typec_altmode_get_drvdata(altmode);
+
+ mutex_lock(&port->lock);
+ tcpm_queue_vdm(port, header, data, count - 1);
+ mod_delayed_work(port->wq, &port->vdm_state_machine, 0);
+ mutex_unlock(&port->lock);
+
+ return 0;
+}
+
+static const struct typec_altmode_ops tcpm_altmode_ops = {
+ .enter = tcpm_altmode_enter,
+ .exit = tcpm_altmode_exit,
+ .vdm = tcpm_altmode_vdm,
+};
+
/*
* PD (data, control) command handling functions
*/
@@ -2539,7 +2642,7 @@ static int tcpm_src_attach(struct tcpm_port *port)
out_disable_pd:
port->tcpc->set_pd_rx(port->tcpc, false);
out_disable_mux:
- tcpm_mux_set(port, TYPEC_MUX_NONE, USB_ROLE_NONE,
+ tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
return ret;
}
@@ -2585,7 +2688,7 @@ static void tcpm_reset_port(struct tcpm_port *port)
tcpm_init_vconn(port);
tcpm_set_current_limit(port, 0, 0);
tcpm_set_polarity(port, TYPEC_POLARITY_CC1);
- tcpm_mux_set(port, TYPEC_MUX_NONE, USB_ROLE_NONE,
+ tcpm_mux_set(port, TYPEC_STATE_SAFE, USB_ROLE_NONE,
TYPEC_ORIENTATION_NONE);
tcpm_set_attached_state(port, false);
port->try_src_count = 0;
@@ -4618,6 +4721,8 @@ struct tcpm_port *tcpm_register_port(struct device *dev, struct tcpc_dev *tcpc)
dev_name(dev), paltmode->svid);
break;
}
+ typec_altmode_set_drvdata(alt, port);
+ alt->ops = &tcpm_altmode_ops;
port->port_altmode[i] = alt;
i++;
paltmode++;
diff --git a/include/linux/usb/tcpm.h b/include/linux/usb/tcpm.h
index b231b9314240..8c3df3e11801 100644
--- a/include/linux/usb/tcpm.h
+++ b/include/linux/usb/tcpm.h
@@ -98,15 +98,6 @@ struct tcpc_config {
#define TCPC_MUX_DP_ENABLED BIT(1) /* DP enabled */
#define TCPC_MUX_POLARITY_INVERTED BIT(2) /* Polarity inverted */

-/* Mux modes, decoded to attributes */
-enum tcpc_mux_mode {
- TYPEC_MUX_NONE = 0, /* Open switch */
- TYPEC_MUX_USB = TCPC_MUX_USB_ENABLED, /* USB only */
- TYPEC_MUX_DP = TCPC_MUX_DP_ENABLED, /* DP only */
- TYPEC_MUX_DOCK = TCPC_MUX_USB_ENABLED | /* Both USB and DP */
- TCPC_MUX_DP_ENABLED,
-};
-
/**
* struct tcpc_dev - Port configuration and callback functions
* @config: Pointer to port configuration
--
2.18.0