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* [PATCH v5] usb: typec: ucsi: add support for separate DP altmode devices
@ 2019-09-06 16:55 Ajay Gupta
  2019-09-13 15:20 ` Heikki Krogerus
  0 siblings, 1 reply; 4+ messages in thread
From: Ajay Gupta @ 2019-09-06 16:55 UTC (permalink / raw)
  To: heikki.krogerus; +Cc: linux-usb, Ajay Gupta

From: Ajay Gupta <ajayg@nvidia.com>

CCGx controller used on NVIDIA GPU card has two separate display
altmode for two DP pin assignments. UCSI specification doesn't
prohibits using separate display altmode.

Current UCSI Type-C framework expects only one display altmode for
all DP pin assignment. This patch squashes two separate display
altmode into single altmode to support controllers with separate
display altmode. We first read all the alternate modes of connector
and then run through it to know if there are separate display
altmodes. If so, it prepares a new port altmode set after squashing
two or more separate altmodes into one.

Signed-off-by: Ajay Gupta <ajayg@nvidia.com>
---
Original discussion on this issue is at [1]

Change from v4->v5
	- Fix comments style as per Heikki's review

1. https://marc.info/?l=linux-usb&m=154905866830998&w=2

 drivers/usb/typec/ucsi/ucsi.c     |  68 +++++++++--
 drivers/usb/typec/ucsi/ucsi.h     |   8 ++
 drivers/usb/typec/ucsi/ucsi_ccg.c | 181 +++++++++++++++++++++++++++++-
 3 files changed, 244 insertions(+), 13 deletions(-)

diff --git a/drivers/usb/typec/ucsi/ucsi.c b/drivers/usb/typec/ucsi/ucsi.c
index ba288b964dc8..2903fb96b893 100644
--- a/drivers/usb/typec/ucsi/ucsi.c
+++ b/drivers/usb/typec/ucsi/ucsi.c
@@ -346,12 +346,17 @@ static int ucsi_register_altmodes(struct ucsi_connector *con, u8 recipient)
 	int max_altmodes = UCSI_MAX_ALTMODES;
 	struct typec_altmode_desc desc;
 	struct ucsi_altmode alt[2];
+	struct ucsi_altmode orig[UCSI_MAX_ALTMODES];
+	struct ucsi_altmode updated[UCSI_MAX_ALTMODES];
+	struct ucsi *ucsi = con->ucsi;
+	bool multi_dp = false;
 	struct ucsi_control ctrl;
 	int num = 1;
 	int ret;
 	int len;
 	int j;
 	int i;
+	int k = 0;
 
 	if (!(con->ucsi->cap.features & UCSI_CAP_ALT_MODE_DETAILS))
 		return 0;
@@ -362,35 +367,74 @@ static int ucsi_register_altmodes(struct ucsi_connector *con, u8 recipient)
 	if (recipient == UCSI_RECIPIENT_CON)
 		max_altmodes = con->ucsi->cap.num_alt_modes;
 
+	memset(orig, 0, sizeof(orig));
+	memset(updated, 0, sizeof(updated));
+
+	/* First get all the alternate modes */
 	for (i = 0; i < max_altmodes;) {
 		memset(alt, 0, sizeof(alt));
 		UCSI_CMD_GET_ALTERNATE_MODES(ctrl, recipient, con->num, i, 1);
 		len = ucsi_run_command(con->ucsi, &ctrl, alt, sizeof(alt));
-		if (len <= 0)
+		/*
+		 * We are collecting all altmodes first and then registering.
+		 * Some type-C device will return zero length data beyond last
+		 * alternate modes. We should not return if length is zero.
+		 */
+		if (len < 0)
 			return len;
 
+		/* We got all altmodes, now break out and register them */
+		if (!len)
+			break;
+
 		/*
 		 * This code is requesting one alt mode at a time, but some PPMs
 		 * may still return two. If that happens both alt modes need be
-		 * registered and the offset for the next alt mode has to be
+		 * saved and the offset for the next alt mode has to be
 		 * incremented.
 		 */
 		num = len / sizeof(alt[0]);
 		i += num;
 
 		for (j = 0; j < num; j++) {
-			if (!alt[j].svid)
-				return 0;
-
-			memset(&desc, 0, sizeof(desc));
-			desc.vdo = alt[j].mid;
-			desc.svid = alt[j].svid;
-			desc.roles = TYPEC_PORT_DRD;
+			if (!alt[j].svid) {
+				/* break out of outer loop and register */
+				i = max_altmodes;
+				break;
+			}
+
+			orig[k].mid = alt[j].mid;
+			orig[k].svid = alt[j].svid;
+			k++;
+		}
+	}
 
-			ret = ucsi_register_altmode(con, &desc, recipient);
-			if (ret)
-				return ret;
+	/*
+	 * Update the original altmode table as some ppms may report
+	 * multiple DP altmodes.
+	 */
+	if (recipient == UCSI_RECIPIENT_CON && ucsi->ppm &&
+	    ucsi->ppm->update_altmodes)
+		multi_dp = ucsi->ppm->update_altmodes(ucsi->ppm, orig, updated);
+
+	/* now register altmodes */
+	for (i = 0; i < max_altmodes; i++) {
+		memset(&desc, 0, sizeof(desc));
+		if (multi_dp && recipient == UCSI_RECIPIENT_CON) {
+			desc.svid = updated[i].svid;
+			desc.vdo = updated[i].mid;
+		} else {
+			desc.svid = orig[i].svid;
+			desc.vdo = orig[i].mid;
 		}
+		desc.roles = TYPEC_PORT_DRD;
+
+		if (!desc.svid)
+			return 0;
+
+		ret = ucsi_register_altmode(con, &desc, recipient);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
diff --git a/drivers/usb/typec/ucsi/ucsi.h b/drivers/usb/typec/ucsi/ucsi.h
index de87d0b8319d..fa6d896c5531 100644
--- a/drivers/usb/typec/ucsi/ucsi.h
+++ b/drivers/usb/typec/ucsi/ucsi.h
@@ -231,6 +231,11 @@ struct ucsi_control {
 #define UCSI_ERROR_DEAD_BATTERY			BIT(5)
 #define UCSI_ERROR_CONTRACT_NEGOTIATION_FAIL	BIT(6)
 
+#define UCSI_SET_NEW_CAM_ENTER(x)		(((x) >> 23) & 0x1)
+#define UCSI_SET_NEW_CAM_GET_AM(x)		(((x) >> 24) & 0xff)
+#define UCSI_SET_NEW_CAM_AM_MASK		(0xff << 24)
+#define UCSI_SET_NEW_CAM_SET_AM(x)		(((x) & 0xff) << 24)
+#define UCSI_CMD_CONNECTOR_MASK			(0x7)
 /* Data structure filled by PPM in response to GET_CAPABILITY command. */
 struct ucsi_capability {
 	u32 attributes;
@@ -363,11 +368,14 @@ struct ucsi_data {
  * @data: memory location to the UCSI data structures
  * @cmd: UCSI command execution routine
  * @sync: Refresh UCSI mailbox (the data structures)
+ * @update_altmodes: Squashes duplicate DP altmodes
  */
 struct ucsi_ppm {
 	struct ucsi_data *data;
 	int (*cmd)(struct ucsi_ppm *, struct ucsi_control *);
 	int (*sync)(struct ucsi_ppm *);
+	bool (*update_altmodes)(struct ucsi_ppm *ppm, struct ucsi_altmode *orig,
+				struct ucsi_altmode *updated);
 };
 
 struct ucsi *ucsi_register_ppm(struct device *dev, struct ucsi_ppm *ppm);
diff --git a/drivers/usb/typec/ucsi/ucsi_ccg.c b/drivers/usb/typec/ucsi/ucsi_ccg.c
index 907e20e1a71e..157ec3246d3c 100644
--- a/drivers/usb/typec/ucsi/ucsi_ccg.c
+++ b/drivers/usb/typec/ucsi/ucsi_ccg.c
@@ -16,6 +16,7 @@
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
+#include <linux/usb/typec_dp.h>
 
 #include <asm/unaligned.h>
 #include "ucsi.h"
@@ -173,6 +174,15 @@ struct ccg_resp {
 	u8 length;
 };
 
+struct ucsi_ccg_altmode {
+	u16 svid;
+	u32 mid;
+	u8 linked_idx;
+	u8 active_idx;
+#define UCSI_MULTI_DP_INDEX	(0xff)
+	bool checked;
+} __packed;
+
 struct ucsi_ccg {
 	struct device *dev;
 	struct ucsi *ucsi;
@@ -197,6 +207,10 @@ struct ucsi_ccg {
 	u16 fw_build;
 	bool run_isr; /* flag to call ISR routine during resume */
 	struct work_struct pm_work;
+
+	bool has_multiple_dp;
+	struct ucsi_ccg_altmode orig[UCSI_MAX_ALTMODES];
+	struct ucsi_ccg_altmode updated[UCSI_MAX_ALTMODES];
 };
 
 static int ccg_read(struct ucsi_ccg *uc, u16 rab, u8 *data, u32 len)
@@ -389,9 +403,23 @@ static int ucsi_ccg_ack_interrupt(struct ucsi_ccg *uc)
 	return ccg_write(uc, CCGX_RAB_INTR_REG, &data, sizeof(data));
 }
 
+static void ucsi_ccg_update_get_current_cam_cmd(struct ucsi_ccg *uc,
+						struct ucsi_data *data)
+{
+	u8 cam, new_cam;
+
+	if (data->cci.data_length == 0x1) {
+		cam = data->message_in[0];
+		new_cam = uc->orig[cam].linked_idx;
+		data->message_in[0] = new_cam;
+		uc->updated[new_cam].active_idx = cam;
+	}
+}
+
 static int ucsi_ccg_sync(struct ucsi_ppm *ppm)
 {
 	struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm);
+	struct ucsi_data *data;
 	int status;
 
 	status = ucsi_ccg_recv_data(uc);
@@ -399,12 +427,162 @@ static int ucsi_ccg_sync(struct ucsi_ppm *ppm)
 		return status;
 
 	/* ack interrupt to allow next command to run */
-	return ucsi_ccg_ack_interrupt(uc);
+	status = ucsi_ccg_ack_interrupt(uc);
+	if (status < 0)
+		return status;
+
+	data = ppm->data;
+	if (data->ctrl.alt.cmd == UCSI_GET_CURRENT_CAM && uc->has_multiple_dp)
+		ucsi_ccg_update_get_current_cam_cmd(uc, data);
+
+	return status;
+}
+
+static bool ucsi_ccg_update_altmodes(struct ucsi_ppm *ppm,
+				     struct ucsi_altmode *orig,
+				     struct ucsi_altmode *updated)
+{
+	struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm);
+	struct ucsi_ccg_altmode *alt, *new_alt;
+	int i, j, k = 0;
+	bool found = false;
+
+	alt = uc->orig;
+	new_alt = uc->updated;
+	memset(uc->updated, 0, sizeof(uc->updated));
+
+	/*
+	 * Copy original connector altmodes to new structure.
+	 * We need this before second loop since second loop
+	 * checks for duplicate altmodes.
+	 */
+	for (i = 0; i < UCSI_MAX_ALTMODES; i++) {
+		alt[i].svid = orig[i].svid;
+		alt[i].mid = orig[i].mid;
+		if (!alt[i].svid)
+			break;
+	}
+
+	for (i = 0; i < UCSI_MAX_ALTMODES; i++) {
+		if (!alt[i].svid)
+			break;
+
+		/* already checked and considered */
+		if (alt[i].checked)
+			continue;
+
+		if (!DP_CONF_GET_PIN_ASSIGN(alt[i].mid)) {
+			/* Found Non DP altmode */
+			new_alt[k].svid = alt[i].svid;
+			new_alt[k].mid |= alt[i].mid;
+			new_alt[k].linked_idx = i;
+			alt[i].linked_idx = k;
+			updated[k].svid = new_alt[k].svid;
+			updated[k].mid = new_alt[k].mid;
+			k++;
+			continue;
+		}
+
+		for (j = i + 1; j < UCSI_MAX_ALTMODES; j++) {
+			if (alt[i].svid != alt[j].svid ||
+			    !DP_CONF_GET_PIN_ASSIGN(alt[j].mid)) {
+				continue;
+			} else {
+				/* Found duplicate DP mode */
+				new_alt[k].svid = alt[i].svid;
+				new_alt[k].mid |= alt[i].mid | alt[j].mid;
+				new_alt[k].linked_idx = UCSI_MULTI_DP_INDEX;
+				alt[i].linked_idx = k;
+				alt[j].linked_idx = k;
+				alt[j].checked = true;
+				found = true;
+			}
+		}
+		if (found) {
+			uc->has_multiple_dp = true;
+		} else {
+			/* Didn't find any duplicate DP altmode */
+			new_alt[k].svid = alt[i].svid;
+			new_alt[k].mid |= alt[i].mid;
+			new_alt[k].linked_idx = i;
+			alt[i].linked_idx = k;
+		}
+		updated[k].svid = new_alt[k].svid;
+		updated[k].mid = new_alt[k].mid;
+		k++;
+	}
+	return found;
+}
+
+static void ucsi_ccg_update_set_new_cam_cmd(struct ucsi_ccg *uc,
+					    struct ucsi_connector *con,
+					    struct ucsi_control *ctrl)
+{
+	struct ucsi_ccg_altmode *new_port, *port;
+	struct typec_altmode *alt = NULL;
+	u8 new_cam, cam, pin;
+	bool enter_new_mode;
+	int i, j, k = 0xff;
+
+	port = uc->orig;
+	new_cam = UCSI_SET_NEW_CAM_GET_AM(ctrl->raw_cmd);
+	new_port = &uc->updated[new_cam];
+	cam = new_port->linked_idx;
+	enter_new_mode = UCSI_SET_NEW_CAM_ENTER(ctrl->raw_cmd);
+
+	/*
+	 * If CAM is UCSI_MULTI_DP_INDEX then this is DP altmode
+	 * with multiple DP mode. Find out CAM for best pin assignement
+	 * among all DP mode. Priorite pin E->D->C after making sure
+	 * the partner supports that pin.
+	 */
+	if (cam == UCSI_MULTI_DP_INDEX) {
+		if (enter_new_mode) {
+			for (i = 0; con->partner_altmode[i]; i++) {
+				alt = con->partner_altmode[i];
+				if (alt->svid == new_port->svid)
+					break;
+			}
+			/*
+			 * alt will always be non NULL since this is
+			 * UCSI_SET_NEW_CAM command and so there will be
+			 * atleast one con->partner_altmode[i] with svid
+			 * matching with new_port->svid.
+			 */
+			for (j = 0; port[j].svid; j++) {
+				pin = DP_CONF_GET_PIN_ASSIGN(port[j].mid);
+				if (alt && port[j].svid == alt->svid &&
+				    (pin & DP_CONF_GET_PIN_ASSIGN(alt->vdo))) {
+					/* prioritize pin E->D->C */
+					if (k == 0xff || (k != 0xff && pin >
+					    DP_CONF_GET_PIN_ASSIGN(port[k].mid))
+					    ) {
+						k = j;
+					}
+				}
+			}
+			cam = k;
+			new_port->active_idx = cam;
+		} else {
+			cam = new_port->active_idx;
+		}
+	}
+	ctrl->raw_cmd &= ~UCSI_SET_NEW_CAM_AM_MASK;
+	ctrl->raw_cmd |= UCSI_SET_NEW_CAM_SET_AM(cam);
 }
 
 static int ucsi_ccg_cmd(struct ucsi_ppm *ppm, struct ucsi_control *ctrl)
 {
 	struct ucsi_ccg *uc = container_of(ppm, struct ucsi_ccg, ppm);
+	struct ucsi_connector *con;
+	int con_index;
+
+	if (ctrl->alt.cmd == UCSI_SET_NEW_CAM && uc->has_multiple_dp) {
+		con_index = ctrl->cmd.data & UCSI_CMD_CONNECTOR_MASK;
+		con = &uc->ucsi->connector[con_index - 1];
+
+		ucsi_ccg_update_set_new_cam_cmd(uc, con, ctrl);
+	}
 
 	ppm->data->ctrl.raw_cmd = ctrl->raw_cmd;
 	return ucsi_ccg_send_data(uc);
@@ -1128,6 +1306,7 @@ static int ucsi_ccg_probe(struct i2c_client *client,
 
 	uc->ppm.cmd = ucsi_ccg_cmd;
 	uc->ppm.sync = ucsi_ccg_sync;
+	uc->ppm.update_altmodes = ucsi_ccg_update_altmodes;
 	uc->dev = dev;
 	uc->client = client;
 	uc->run_isr = true;
-- 
2.17.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v5] usb: typec: ucsi: add support for separate DP altmode devices
  2019-09-06 16:55 [PATCH v5] usb: typec: ucsi: add support for separate DP altmode devices Ajay Gupta
@ 2019-09-13 15:20 ` Heikki Krogerus
  2019-09-17 21:41   ` Ajay Gupta
  0 siblings, 1 reply; 4+ messages in thread
From: Heikki Krogerus @ 2019-09-13 15:20 UTC (permalink / raw)
  To: Ajay Gupta; +Cc: linux-usb, Ajay Gupta

Hi Ajay,

On Fri, Sep 06, 2019 at 09:55:16AM -0700, Ajay Gupta wrote:
> From: Ajay Gupta <ajayg@nvidia.com>
> 
> CCGx controller used on NVIDIA GPU card has two separate display
> altmode for two DP pin assignments. UCSI specification doesn't
> prohibits using separate display altmode.
> 
> Current UCSI Type-C framework expects only one display altmode for
> all DP pin assignment. This patch squashes two separate display
> altmode into single altmode to support controllers with separate
> display altmode. We first read all the alternate modes of connector
> and then run through it to know if there are separate display
> altmodes. If so, it prepares a new port altmode set after squashing
> two or more separate altmodes into one.

I'm going to go over this one more time during the merge window. I
have an idea how to improve this. Please bear with me. I have to make
sure all options were considered.

I'm really sorry to block this for so long, but I'm just really really
afraid of mixing special case solutions like this into otherwise
generic code. They always make it difficult to modify the code later,
and unfortunately we have them all over the kernel. Look at the serial
driver 8250_core/port/*.cas an example. Ideally we should be able to
"modularize" the whole alternate mode handling in the ucsi driver
since there are now two different ways the PPMs can handle them
instead of simply mixing the support for the new method straight into
the existing structures.

thanks,

-- 
heikki

^ permalink raw reply	[flat|nested] 4+ messages in thread

* RE: [PATCH v5] usb: typec: ucsi: add support for separate DP altmode devices
  2019-09-13 15:20 ` Heikki Krogerus
@ 2019-09-17 21:41   ` Ajay Gupta
  2019-09-19 12:23     ` Heikki Krogerus
  0 siblings, 1 reply; 4+ messages in thread
From: Ajay Gupta @ 2019-09-17 21:41 UTC (permalink / raw)
  To: Heikki Krogerus, Ajay Gupta; +Cc: linux-usb

Hi Heikki,

> -----Original Message-----
> From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> Sent: Friday, September 13, 2019 8:20 AM
> To: Ajay Gupta <ajaykuee@gmail.com>
> Cc: linux-usb@vger.kernel.org; Ajay Gupta <ajayg@nvidia.com>
> Subject: Re: [PATCH v5] usb: typec: ucsi: add support for separate DP altmode
> devices
> 
> Hi Ajay,
> 
> On Fri, Sep 06, 2019 at 09:55:16AM -0700, Ajay Gupta wrote:
> > From: Ajay Gupta <ajayg@nvidia.com>
> >
> > CCGx controller used on NVIDIA GPU card has two separate display
> > altmode for two DP pin assignments. UCSI specification doesn't
> > prohibits using separate display altmode.
> >
> > Current UCSI Type-C framework expects only one display altmode for all
> > DP pin assignment. This patch squashes two separate display altmode
> > into single altmode to support controllers with separate display
> > altmode. We first read all the alternate modes of connector and then
> > run through it to know if there are separate display altmodes. If so,
> > it prepares a new port altmode set after squashing two or more
> > separate altmodes into one.
> 
> I'm going to go over this one more time during the merge window. I have an
> idea how to improve this. Please bear with me. I have to make sure all options
> were considered.
> 
> I'm really sorry to block this for so long, but I'm just really really afraid of
> mixing special case solutions like this into otherwise generic code.

I can update the patch to make sure generic code flow remains as-is and special
case is executed only for UCSI controllers which needs squashing of duplicate
DP altmodes.
We can use the new function pointer update_altmode() added in "struct ucsi_ppm" in v5
of my patch for this purpose.

if (recipient == UCSI_RECIPIENT_CON && ucsi->ppm && ucsi->ppm->update_altmodes)
	Get all the altmodes first, pass it to update_altmodes() for squashing if needed,
	and then register each altmodes.
else
	Use the current method where we get and register one altmode at a time.

Please let me know if this looks fine to you.

Thanks
> nvpublic
> They always
> make it difficult to modify the code later, and unfortunately we have them all
> over the kernel. Look at the serial driver 8250_core/port/*.cas an example.
> Ideally we should be able to "modularize" the whole alternate mode handling
> in the ucsi driver since there are now two different ways the PPMs can handle
> them instead of simply mixing the support for the new method straight into
> the existing structures.
> 
> thanks,
> 
> --
> heikki

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [PATCH v5] usb: typec: ucsi: add support for separate DP altmode devices
  2019-09-17 21:41   ` Ajay Gupta
@ 2019-09-19 12:23     ` Heikki Krogerus
  0 siblings, 0 replies; 4+ messages in thread
From: Heikki Krogerus @ 2019-09-19 12:23 UTC (permalink / raw)
  To: Ajay Gupta; +Cc: Ajay Gupta, linux-usb

On Tue, Sep 17, 2019 at 09:41:49PM +0000, Ajay Gupta wrote:
> Hi Heikki,
> 
> > -----Original Message-----
> > From: Heikki Krogerus <heikki.krogerus@linux.intel.com>
> > Sent: Friday, September 13, 2019 8:20 AM
> > To: Ajay Gupta <ajaykuee@gmail.com>
> > Cc: linux-usb@vger.kernel.org; Ajay Gupta <ajayg@nvidia.com>
> > Subject: Re: [PATCH v5] usb: typec: ucsi: add support for separate DP altmode
> > devices
> > 
> > Hi Ajay,
> > 
> > On Fri, Sep 06, 2019 at 09:55:16AM -0700, Ajay Gupta wrote:
> > > From: Ajay Gupta <ajayg@nvidia.com>
> > >
> > > CCGx controller used on NVIDIA GPU card has two separate display
> > > altmode for two DP pin assignments. UCSI specification doesn't
> > > prohibits using separate display altmode.
> > >
> > > Current UCSI Type-C framework expects only one display altmode for all
> > > DP pin assignment. This patch squashes two separate display altmode
> > > into single altmode to support controllers with separate display
> > > altmode. We first read all the alternate modes of connector and then
> > > run through it to know if there are separate display altmodes. If so,
> > > it prepares a new port altmode set after squashing two or more
> > > separate altmodes into one.
> > 
> > I'm going to go over this one more time during the merge window. I have an
> > idea how to improve this. Please bear with me. I have to make sure all options
> > were considered.
> > 
> > I'm really sorry to block this for so long, but I'm just really really afraid of
> > mixing special case solutions like this into otherwise generic code.
> 
> I can update the patch to make sure generic code flow remains as-is and special
> case is executed only for UCSI controllers which needs squashing of duplicate
> DP altmodes.
> We can use the new function pointer update_altmode() added in "struct ucsi_ppm" in v5
> of my patch for this purpose.
> 
> if (recipient == UCSI_RECIPIENT_CON && ucsi->ppm && ucsi->ppm->update_altmodes)
> 	Get all the altmodes first, pass it to update_altmodes() for squashing if needed,
> 	and then register each altmodes.
> else
> 	Use the current method where we get and register one altmode at a time.
> 
> Please let me know if this looks fine to you.

No. Please wait. I'm refactoring ucsi.c. I'm going to redo the I/O
completely, and also do some long waited cleanups. Those changes
should make handling this case also much easier.

thanks,

-- 
heikki

^ permalink raw reply	[flat|nested] 4+ messages in thread

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2019-09-06 16:55 [PATCH v5] usb: typec: ucsi: add support for separate DP altmode devices Ajay Gupta
2019-09-13 15:20 ` Heikki Krogerus
2019-09-17 21:41   ` Ajay Gupta
2019-09-19 12:23     ` Heikki Krogerus

Linux-USB Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-usb/0 linux-usb/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-usb linux-usb/ https://lore.kernel.org/linux-usb \
		linux-usb@vger.kernel.org linux-usb@archiver.kernel.org
	public-inbox-index linux-usb


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-usb


AGPL code for this site: git clone https://public-inbox.org/ public-inbox