[PATCH V5 0/3] rpmsg signaling/flowcontrol patches

[PATCH V5 0/3] rpmsg signaling/flowcontrol patches

[Sarannya S]

Added new IOCTLS- RPMSG_GET_SIGNAL_IOCTL and RPMSG_SET_SIGNAL_IOCTL
to get/set the rpmsg char device's flow control signal.
Update the cmd name 'RPM_CMD_SIGNALS' to 'GLINK_CMD_SIGNALS'.
Addressed review comments to change variable names/descriptions. 

Chris Lew (2):
  rpmsg: glink: Add support to handle signals command
  rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support

Deepak Kumar Singh (1):
  rpmsg: core: Add signal API support

 drivers/rpmsg/qcom_glink_native.c | 63 +++++++++++++++++++++++++++++++++++++++
 drivers/rpmsg/rpmsg_char.c        | 58 ++++++++++++++++++++++++++++++-----
 drivers/rpmsg/rpmsg_core.c        | 20 +++++++++++++
 drivers/rpmsg/rpmsg_internal.h    |  2 ++
 include/linux/rpmsg.h             | 15 ++++++++++
 include/uapi/linux/rpmsg.h        | 12 +++++++-
 6 files changed, 162 insertions(+), 8 deletions(-)

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH V5 1/3] rpmsg: core: Add signal API support

[Sarannya S]

From: Deepak Kumar Singh <quic_deesin@quicinc.com>

Some transports like Glink support the state notifications between
clients using flow control signals similar to serial protocol signals.
Local glink client drivers can send and receive flow control status
to glink clients running on remote processors.

Add APIs to support sending and receiving of flow control status by
rpmsg clients.

Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
---
 drivers/rpmsg/rpmsg_core.c     | 20 ++++++++++++++++++++
 drivers/rpmsg/rpmsg_internal.h |  2 ++
 2 files changed, 22 insertions(+)

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index a2207c0..86b4912 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -331,6 +331,24 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
 /**
+ * rpmsg_set_flow_control() - sets/clears serial flow control signals
+ * @ept:	the rpmsg endpoint
+ * @enable:	pause/resume incoming data flow
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->set_flow_control)
+		return -ENXIO;
+
+	return ept->ops->set_flow_control(ept, enable);
+}
+EXPORT_SYMBOL(rpmsg_set_flow_control);
+
+/**
  * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
  * @ept: the rpmsg endpoint
  *
@@ -539,6 +557,8 @@ static int rpmsg_dev_probe(struct device *dev)
 
 		rpdev->ept = ept;
 		rpdev->src = ept->addr;
+
+		ept->flow_cb = rpdrv->flowcontrol;
 	}
 
 	err = rpdrv->probe(rpdev);
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index 39b646d..4fea45a 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -55,6 +55,7 @@ struct rpmsg_device_ops {
  * @trysendto:		see @rpmsg_trysendto(), optional
  * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
  * @poll:		see @rpmsg_poll(), optional
+ * @set_flow_control:	see @rpmsg_set_flow_control(), optional
  * @get_mtu:		see @rpmsg_get_mtu(), optional
  *
  * Indirection table for the operations that a rpmsg backend should implement.
@@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops {
 			     void *data, int len);
 	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
 			     poll_table *wait);
+	int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable);
 	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
 };
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH V5 1/3] rpmsg: core: Add signal API support

[Arnaud POULIQUEN]

Hi,


On 4/18/23 10:48, Sarannya S wrote:
> From: Deepak Kumar Singh <quic_deesin@quicinc.com>
> 
> Some transports like Glink support the state notifications between
> clients using flow control signals similar to serial protocol signals.
> Local glink client drivers can send and receive flow control status
> to glink clients running on remote processors.
> 
> Add APIs to support sending and receiving of flow control status by
> rpmsg clients.
> 
> Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
> Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
> ---
>  drivers/rpmsg/rpmsg_core.c     | 20 ++++++++++++++++++++
>  drivers/rpmsg/rpmsg_internal.h |  2 ++
>  2 files changed, 22 insertions(+)
> 
> diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
> index a2207c0..86b4912 100644
> --- a/drivers/rpmsg/rpmsg_core.c
> +++ b/drivers/rpmsg/rpmsg_core.c
> @@ -331,6 +331,24 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
>  EXPORT_SYMBOL(rpmsg_trysend_offchannel);
>  
>  /**
> + * rpmsg_set_flow_control() - sets/clears serial flow control signals
> + * @ept:	the rpmsg endpoint
> + * @enable:	pause/resume incoming data flow
> + *
> + * Return: 0 on success and an appropriate error value on failure.
> + */
> +int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)


Regression since V4[1]

In V4 version the function was:

int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable, u32 dst)

Following comments on V3 [2]

Without dst parameter it is not compatible with the rpmsg_virtio backend


[1]https://lkml.org/lkml/2022/12/7/506
[2]https://www.spinics.net/lists/kernel/msg4573082.html

Regards
Arnaud

> +{
> +	if (WARN_ON(!ept))
> +		return -EINVAL;
> +	if (!ept->ops->set_flow_control)
> +		return -ENXIO;
> +
> +	return ept->ops->set_flow_control(ept, enable);
> +}
> +EXPORT_SYMBOL(rpmsg_set_flow_control);
> +
> +/**
>   * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
>   * @ept: the rpmsg endpoint
>   *
> @@ -539,6 +557,8 @@ static int rpmsg_dev_probe(struct device *dev)
>  
>  		rpdev->ept = ept;
>  		rpdev->src = ept->addr;
> +
> +		ept->flow_cb = rpdrv->flowcontrol;
>  	}
>  
>  	err = rpdrv->probe(rpdev);
> diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
> index 39b646d..4fea45a 100644
> --- a/drivers/rpmsg/rpmsg_internal.h
> +++ b/drivers/rpmsg/rpmsg_internal.h
> @@ -55,6 +55,7 @@ struct rpmsg_device_ops {
>   * @trysendto:		see @rpmsg_trysendto(), optional
>   * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
>   * @poll:		see @rpmsg_poll(), optional
> + * @set_flow_control:	see @rpmsg_set_flow_control(), optional
>   * @get_mtu:		see @rpmsg_get_mtu(), optional
>   *
>   * Indirection table for the operations that a rpmsg backend should implement.
> @@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops {
>  			     void *data, int len);
>  	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
>  			     poll_table *wait);
> +	int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable);
>  	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
>  };
>  

Re: [PATCH V5 1/3] rpmsg: core: Add signal API support

[Bjorn Andersson]

On Wed, Apr 19, 2023 at 11:53:49AM +0200, Arnaud POULIQUEN wrote:
> Hi,
> 
> 
> On 4/18/23 10:48, Sarannya S wrote:
> > From: Deepak Kumar Singh <quic_deesin@quicinc.com>
> > 
> > Some transports like Glink support the state notifications between
> > clients using flow control signals similar to serial protocol signals.
> > Local glink client drivers can send and receive flow control status
> > to glink clients running on remote processors.
> > 
> > Add APIs to support sending and receiving of flow control status by
> > rpmsg clients.
> > 
> > Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
> > Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
> > ---
> >  drivers/rpmsg/rpmsg_core.c     | 20 ++++++++++++++++++++
> >  drivers/rpmsg/rpmsg_internal.h |  2 ++
> >  2 files changed, 22 insertions(+)
> > 
> > diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
> > index a2207c0..86b4912 100644
> > --- a/drivers/rpmsg/rpmsg_core.c
> > +++ b/drivers/rpmsg/rpmsg_core.c
> > @@ -331,6 +331,24 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
> >  EXPORT_SYMBOL(rpmsg_trysend_offchannel);
> >  
> >  /**
> > + * rpmsg_set_flow_control() - sets/clears serial flow control signals
> > + * @ept:	the rpmsg endpoint
> > + * @enable:	pause/resume incoming data flow
> > + *
> > + * Return: 0 on success and an appropriate error value on failure.
> > + */
> > +int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
> 
> 
> Regression since V4[1]
> 
> In V4 version the function was:
> 
> int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable, u32 dst)
> 
> Following comments on V3 [2]
> 
> Without dst parameter it is not compatible with the rpmsg_virtio backend
> 

You're right, and I missed that this was gone again. Thanks for pointing
it out. I've backed this series out of rpmsg-next again.

v6 seems to carry the correct argument again...

Regards,
Bjorn

> 
> [1]https://lkml.org/lkml/2022/12/7/506
> [2]https://www.spinics.net/lists/kernel/msg4573082.html
> 
> Regards
> Arnaud
> 
> > +{
> > +	if (WARN_ON(!ept))
> > +		return -EINVAL;
> > +	if (!ept->ops->set_flow_control)
> > +		return -ENXIO;
> > +
> > +	return ept->ops->set_flow_control(ept, enable);
> > +}
> > +EXPORT_SYMBOL(rpmsg_set_flow_control);
> > +
> > +/**
> >   * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
> >   * @ept: the rpmsg endpoint
> >   *
> > @@ -539,6 +557,8 @@ static int rpmsg_dev_probe(struct device *dev)
> >  
> >  		rpdev->ept = ept;
> >  		rpdev->src = ept->addr;
> > +
> > +		ept->flow_cb = rpdrv->flowcontrol;
> >  	}
> >  
> >  	err = rpdrv->probe(rpdev);
> > diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
> > index 39b646d..4fea45a 100644
> > --- a/drivers/rpmsg/rpmsg_internal.h
> > +++ b/drivers/rpmsg/rpmsg_internal.h
> > @@ -55,6 +55,7 @@ struct rpmsg_device_ops {
> >   * @trysendto:		see @rpmsg_trysendto(), optional
> >   * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
> >   * @poll:		see @rpmsg_poll(), optional
> > + * @set_flow_control:	see @rpmsg_set_flow_control(), optional
> >   * @get_mtu:		see @rpmsg_get_mtu(), optional
> >   *
> >   * Indirection table for the operations that a rpmsg backend should implement.
> > @@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops {
> >  			     void *data, int len);
> >  	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
> >  			     poll_table *wait);
> > +	int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable);
> >  	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
> >  };
> >  

[PATCH V5 2/3] rpmsg: glink: Add support to handle signals command

[Sarannya S]

From: Chris Lew <quic_clew@quicinc.com>

Remote peripherals send signal notifications over glink with commandID 15.

Add support to send and receive the signal command and based signals
enable or disable flow control with remote host.

Signed-off-by: Chris Lew <quic_clew@quicinc.com>
Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
---
 drivers/rpmsg/qcom_glink_native.c | 63 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 63 insertions(+)

diff --git a/drivers/rpmsg/qcom_glink_native.c b/drivers/rpmsg/qcom_glink_native.c
index 01d2805..3a58b1d 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -16,6 +16,7 @@
 #include <linux/rpmsg.h>
 #include <linux/sizes.h>
 #include <linux/slab.h>
+#include <linux/termios.h>
 #include <linux/workqueue.h>
 #include <linux/mailbox_client.h>
 
@@ -197,9 +198,15 @@ static const struct rpmsg_endpoint_ops glink_endpoint_ops;
 #define GLINK_CMD_TX_DATA_CONT		12
 #define GLINK_CMD_READ_NOTIF		13
 #define GLINK_CMD_RX_DONE_W_REUSE	14
+#define GLINK_CMD_SIGNALS		15
 
 #define GLINK_FEATURE_INTENTLESS	BIT(1)
 
+#define NATIVE_DTR_SIG			NATIVE_DSR_SIG
+#define NATIVE_DSR_SIG			BIT(31)
+#define NATIVE_RTS_SIG			NATIVE_CTS_SIG
+#define NATIVE_CTS_SIG			BIT(30)
+
 static void qcom_glink_rx_done_work(struct work_struct *work);
 
 static struct glink_channel *qcom_glink_alloc_channel(struct qcom_glink *glink,
@@ -1014,6 +1021,57 @@ static int qcom_glink_rx_open_ack(struct qcom_glink *glink, unsigned int lcid)
 	return 0;
 }
 
+/**
+ * qcom_glink_set_flow_control() - convert a signal cmd to wire format and
+ * 				   transmit
+ * @ept:	Rpmsg endpoint for channel.
+ * @enable:	True/False - enable or disable flow control
+ *
+ * Return: 0 on success or standard Linux error code.
+ */
+static int qcom_glink_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
+{
+	struct glink_channel *channel = to_glink_channel(ept);
+	struct qcom_glink *glink = channel->glink;
+	struct glink_msg msg;
+	u32 sigs = 0;
+
+	if (enable)
+		sigs |= NATIVE_DTR_SIG | NATIVE_RTS_SIG;
+
+	msg.cmd = cpu_to_le16(GLINK_CMD_SIGNALS);
+	msg.param1 = cpu_to_le16(channel->lcid);
+	msg.param2 = cpu_to_le32(sigs);
+
+	return qcom_glink_tx(glink, &msg, sizeof(msg), NULL, 0, true);
+}
+
+static int qcom_glink_handle_signals(struct qcom_glink *glink,
+				     unsigned int rcid, unsigned int sigs)
+{
+	struct glink_channel *channel;
+	unsigned long flags;
+	bool enable = false;
+
+	spin_lock_irqsave(&glink->idr_lock, flags);
+	channel = idr_find(&glink->rcids, rcid);
+	spin_unlock_irqrestore(&glink->idr_lock, flags);
+	if (!channel) {
+		dev_err(glink->dev, "signal for non-existing channel\n");
+		return -EINVAL;
+	}
+
+	if (!channel->ept.flow_cb)
+		return 0;
+
+	if (sigs & (NATIVE_DSR_SIG | NATIVE_CTS_SIG))
+		enable = true;
+
+	channel->ept.flow_cb(channel->ept.rpdev, channel->ept.priv, enable);
+
+	return 0;
+}
+
 void qcom_glink_native_rx(struct qcom_glink *glink)
 {
 	struct glink_msg msg;
@@ -1075,6 +1133,10 @@ void qcom_glink_native_rx(struct qcom_glink *glink)
 			qcom_glink_handle_intent_req_ack(glink, param1, param2);
 			qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
 			break;
+		case GLINK_CMD_SIGNALS:
+			qcom_glink_handle_signals(glink, param1, param2);
+			qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
+			break;
 		default:
 			dev_err(glink->dev, "unhandled rx cmd: %d\n", cmd);
 			ret = -EINVAL;
@@ -1449,6 +1511,7 @@ static const struct rpmsg_endpoint_ops glink_endpoint_ops = {
 	.sendto = qcom_glink_sendto,
 	.trysend = qcom_glink_trysend,
 	.trysendto = qcom_glink_trysendto,
+	.set_flow_control = qcom_glink_set_flow_control,
 };
 
 static void qcom_glink_rpdev_release(struct device *dev)
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH V5 3/3] rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support

[Sarannya S]

From: Chris Lew <quic_clew@quicinc.com>

Add RPMSG_GET_SIGNAL_IOCTL and RPMSG_SET_SIGNAL_IOCTL ioctl support for
rpmsg char device nodes to get/set the low level transport signals.

Signed-off-by: Chris Lew <quic_clew@quicinc.com>
Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
---
 drivers/rpmsg/rpmsg_char.c | 58 ++++++++++++++++++++++++++++++++++++++++------
 include/linux/rpmsg.h      | 15 ++++++++++++
 include/uapi/linux/rpmsg.h | 12 +++++++++-
 3 files changed, 77 insertions(+), 8 deletions(-)

diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index a271fce..efe14f8 100644
--- a/drivers/rpmsg/rpmsg_char.c
+++ b/drivers/rpmsg/rpmsg_char.c
@@ -23,6 +23,7 @@
 #include <linux/rpmsg.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
+#include <linux/termios.h>
 #include <linux/uaccess.h>
 #include <uapi/linux/rpmsg.h>
 
@@ -68,6 +69,8 @@ struct rpmsg_eptdev {
 	struct sk_buff_head queue;
 	wait_queue_head_t readq;
 
+	u32 remote_signals;
+	bool flow_control;
 };
 
 int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
@@ -110,7 +113,22 @@ static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
 	skb_queue_tail(&eptdev->queue, skb);
 	spin_unlock(&eptdev->queue_lock);
 
-	/* wake up any blocking processes, waiting for new data */
+	wake_up_interruptible(&eptdev->readq);
+
+	return 0;
+}
+
+static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable)
+{
+	struct rpmsg_eptdev *eptdev = priv;
+
+	if (enable)
+		eptdev->remote_signals = RPMSG_FLOW_CONTROL_ON;
+	else
+		eptdev->remote_signals = 0;
+
+	eptdev->flow_control = true;
+
 	wake_up_interruptible(&eptdev->readq);
 
 	return 0;
@@ -152,6 +170,7 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
 		return -EINVAL;
 	}
 
+	ept->flow_cb = rpmsg_ept_flow_cb;
 	eptdev->ept = ept;
 	filp->private_data = eptdev;
 	mutex_unlock(&eptdev->ept_lock);
@@ -172,6 +191,7 @@ static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
 		eptdev->ept = NULL;
 	}
 	mutex_unlock(&eptdev->ept_lock);
+	eptdev->flow_control = false;
 
 	/* Discard all SKBs */
 	skb_queue_purge(&eptdev->queue);
@@ -285,6 +305,9 @@ static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
 	if (!skb_queue_empty(&eptdev->queue))
 		mask |= EPOLLIN | EPOLLRDNORM;
 
+	if (eptdev->flow_control)
+		mask |= EPOLLPRI;
+
 	mutex_lock(&eptdev->ept_lock);
 	mask |= rpmsg_poll(eptdev->ept, filp, wait);
 	mutex_unlock(&eptdev->ept_lock);
@@ -297,14 +320,35 @@ static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
 {
 	struct rpmsg_eptdev *eptdev = fp->private_data;
 
-	if (cmd != RPMSG_DESTROY_EPT_IOCTL)
-		return -EINVAL;
+	bool set;
+	u32 val;
+	int ret;
 
-	/* Don't allow to destroy a default endpoint. */
-	if (eptdev->default_ept)
-		return -EINVAL;
+	switch (cmd) {
+	case RPMSG_GET_SIGNAL_IOCTL:
+		eptdev->flow_control = false;
+		ret = put_user(eptdev->remote_signals, (int __user *)arg);
+		break;
+	case RPMSG_SET_SIGNAL_IOCTL:
+		ret = get_user(val, (int __user *)arg);
+		if (ret)
+			break;
+		set = (val & RPMSG_FLOW_CONTROL_ON) ? true : false;
+		ret = rpmsg_set_flow_control(eptdev->ept, set);
+		break;
+	case RPMSG_DESTROY_EPT_IOCTL:
+		/* Don't allow to destroy a default endpoint. */
+		if (eptdev->default_ept) {
+			ret = -EINVAL;
+			break;
+		}
+		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
+		break;
+	default:
+		ret = -EINVAL;
+	}
 
-	return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
+	return ret;
 }
 
 static const struct file_operations rpmsg_eptdev_fops = {
diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
index 523c98b..cc7a917 100644
--- a/include/linux/rpmsg.h
+++ b/include/linux/rpmsg.h
@@ -64,12 +64,14 @@ struct rpmsg_device {
 };
 
 typedef int (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32);
+typedef int (*rpmsg_flowcontrol_cb_t)(struct rpmsg_device *, void *, bool);
 
 /**
  * struct rpmsg_endpoint - binds a local rpmsg address to its user
  * @rpdev: rpmsg channel device
  * @refcount: when this drops to zero, the ept is deallocated
  * @cb: rx callback handler
+ * @flow_cb: remote flow control callback handler
  * @cb_lock: must be taken before accessing/changing @cb
  * @addr: local rpmsg address
  * @priv: private data for the driver's use
@@ -92,6 +94,7 @@ struct rpmsg_endpoint {
 	struct rpmsg_device *rpdev;
 	struct kref refcount;
 	rpmsg_rx_cb_t cb;
+	rpmsg_flowcontrol_cb_t flow_cb;
 	struct mutex cb_lock;
 	u32 addr;
 	void *priv;
@@ -106,6 +109,7 @@ struct rpmsg_endpoint {
  * @probe: invoked when a matching rpmsg channel (i.e. device) is found
  * @remove: invoked when the rpmsg channel is removed
  * @callback: invoked when an inbound message is received on the channel
+ * @flowcontrol: invoked when remote side flow control status is received
  */
 struct rpmsg_driver {
 	struct device_driver drv;
@@ -113,6 +117,7 @@ struct rpmsg_driver {
 	int (*probe)(struct rpmsg_device *dev);
 	void (*remove)(struct rpmsg_device *dev);
 	int (*callback)(struct rpmsg_device *, void *, int, void *, u32);
+	int (*flowcontrol)(struct rpmsg_device *, void *, bool);
 };
 
 static inline u16 rpmsg16_to_cpu(struct rpmsg_device *rpdev, __rpmsg16 val)
@@ -192,6 +197,8 @@ __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
 
 ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
 
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable);
+
 #else
 
 static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev,
@@ -316,6 +323,14 @@ static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
 	return -ENXIO;
 }
 
+static inline int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
+{
+	/* This shouldn't be possible */
+	WARN_ON(1);
+
+	return -ENXIO;
+}
+
 #endif /* IS_ENABLED(CONFIG_RPMSG) */
 
 /* use a macro to avoid include chaining to get THIS_MODULE */
diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
index 1637e68..c549649 100644
--- a/include/uapi/linux/rpmsg.h
+++ b/include/uapi/linux/rpmsg.h
@@ -10,7 +10,7 @@
 #include <linux/types.h>
 
 #define RPMSG_ADDR_ANY		0xFFFFFFFF
-
+#define RPMSG_FLOW_CONTROL_ON	0x001
 /**
  * struct rpmsg_endpoint_info - endpoint info representation
  * @name: name of service
@@ -43,4 +43,14 @@ struct rpmsg_endpoint_info {
  */
 #define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)
 
+/**
+ * Get the remote rpmsg char device's flow control signal.
+ */
+#define RPMSG_GET_SIGNAL_IOCTL _IOW(0xb5, 0x5, struct rpmsg_endpoint_info)
+
+/**
+ * Set the flow control for the local rpmsg char device.
+ */
+#define RPMSG_SET_SIGNAL_IOCTL _IOW(0xb5, 0x6, struct rpmsg_endpoint_info)
+
 #endif
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH V5 3/3] rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support

[Arnaud POULIQUEN]

On 4/18/23 10:48, Sarannya S wrote:
> From: Chris Lew <quic_clew@quicinc.com>
> 
> Add RPMSG_GET_SIGNAL_IOCTL and RPMSG_SET_SIGNAL_IOCTL ioctl support for
> rpmsg char device nodes to get/set the low level transport signals.


Quite difficult to follow this series as there are two V5...

If I am not mistaken the comment from Bjorn in the first V5[1] has not been
addressed

[1] https://www.spinics.net/lists/linux-arm-msm/msg145036.html

Regards
Arnaud

> 
> Signed-off-by: Chris Lew <quic_clew@quicinc.com>
> Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
> Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
> ---
>  drivers/rpmsg/rpmsg_char.c | 58 ++++++++++++++++++++++++++++++++++++++++------
>  include/linux/rpmsg.h      | 15 ++++++++++++
>  include/uapi/linux/rpmsg.h | 12 +++++++++-
>  3 files changed, 77 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
> index a271fce..efe14f8 100644
> --- a/drivers/rpmsg/rpmsg_char.c
> +++ b/drivers/rpmsg/rpmsg_char.c
> @@ -23,6 +23,7 @@
>  #include <linux/rpmsg.h>
>  #include <linux/skbuff.h>
>  #include <linux/slab.h>
> +#include <linux/termios.h>
>  #include <linux/uaccess.h>
>  #include <uapi/linux/rpmsg.h>
>  
> @@ -68,6 +69,8 @@ struct rpmsg_eptdev {
>  	struct sk_buff_head queue;
>  	wait_queue_head_t readq;
>  
> +	u32 remote_signals;
> +	bool flow_control;
>  };
>  
>  int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
> @@ -110,7 +113,22 @@ static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
>  	skb_queue_tail(&eptdev->queue, skb);
>  	spin_unlock(&eptdev->queue_lock);
>  
> -	/* wake up any blocking processes, waiting for new data */
> +	wake_up_interruptible(&eptdev->readq);
> +
> +	return 0;
> +}
> +
> +static int rpmsg_ept_flow_cb(struct rpmsg_device *rpdev, void *priv, bool enable)
> +{
> +	struct rpmsg_eptdev *eptdev = priv;
> +
> +	if (enable)
> +		eptdev->remote_signals = RPMSG_FLOW_CONTROL_ON;
> +	else
> +		eptdev->remote_signals = 0;
> +
> +	eptdev->flow_control = true;
> +
>  	wake_up_interruptible(&eptdev->readq);
>  
>  	return 0;
> @@ -152,6 +170,7 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
>  		return -EINVAL;
>  	}
>  
> +	ept->flow_cb = rpmsg_ept_flow_cb;
>  	eptdev->ept = ept;
>  	filp->private_data = eptdev;
>  	mutex_unlock(&eptdev->ept_lock);
> @@ -172,6 +191,7 @@ static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
>  		eptdev->ept = NULL;
>  	}
>  	mutex_unlock(&eptdev->ept_lock);
> +	eptdev->flow_control = false;
>  
>  	/* Discard all SKBs */
>  	skb_queue_purge(&eptdev->queue);
> @@ -285,6 +305,9 @@ static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
>  	if (!skb_queue_empty(&eptdev->queue))
>  		mask |= EPOLLIN | EPOLLRDNORM;
>  
> +	if (eptdev->flow_control)
> +		mask |= EPOLLPRI;
> +
>  	mutex_lock(&eptdev->ept_lock);
>  	mask |= rpmsg_poll(eptdev->ept, filp, wait);
>  	mutex_unlock(&eptdev->ept_lock);
> @@ -297,14 +320,35 @@ static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
>  {
>  	struct rpmsg_eptdev *eptdev = fp->private_data;
>  
> -	if (cmd != RPMSG_DESTROY_EPT_IOCTL)
> -		return -EINVAL;
> +	bool set;
> +	u32 val;
> +	int ret;
>  
> -	/* Don't allow to destroy a default endpoint. */
> -	if (eptdev->default_ept)
> -		return -EINVAL;
> +	switch (cmd) {
> +	case RPMSG_GET_SIGNAL_IOCTL:
> +		eptdev->flow_control = false;
> +		ret = put_user(eptdev->remote_signals, (int __user *)arg);
> +		break;
> +	case RPMSG_SET_SIGNAL_IOCTL:
> +		ret = get_user(val, (int __user *)arg);
> +		if (ret)
> +			break;
> +		set = (val & RPMSG_FLOW_CONTROL_ON) ? true : false;
> +		ret = rpmsg_set_flow_control(eptdev->ept, set);
> +		break;
> +	case RPMSG_DESTROY_EPT_IOCTL:
> +		/* Don't allow to destroy a default endpoint. */
> +		if (eptdev->default_ept) {
> +			ret = -EINVAL;
> +			break;
> +		}
> +		ret = rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
>  
> -	return rpmsg_chrdev_eptdev_destroy(&eptdev->dev, NULL);
> +	return ret;
>  }
>  
>  static const struct file_operations rpmsg_eptdev_fops = {
> diff --git a/include/linux/rpmsg.h b/include/linux/rpmsg.h
> index 523c98b..cc7a917 100644
> --- a/include/linux/rpmsg.h
> +++ b/include/linux/rpmsg.h
> @@ -64,12 +64,14 @@ struct rpmsg_device {
>  };
>  
>  typedef int (*rpmsg_rx_cb_t)(struct rpmsg_device *, void *, int, void *, u32);
> +typedef int (*rpmsg_flowcontrol_cb_t)(struct rpmsg_device *, void *, bool);
>  
>  /**
>   * struct rpmsg_endpoint - binds a local rpmsg address to its user
>   * @rpdev: rpmsg channel device
>   * @refcount: when this drops to zero, the ept is deallocated
>   * @cb: rx callback handler
> + * @flow_cb: remote flow control callback handler
>   * @cb_lock: must be taken before accessing/changing @cb
>   * @addr: local rpmsg address
>   * @priv: private data for the driver's use
> @@ -92,6 +94,7 @@ struct rpmsg_endpoint {
>  	struct rpmsg_device *rpdev;
>  	struct kref refcount;
>  	rpmsg_rx_cb_t cb;
> +	rpmsg_flowcontrol_cb_t flow_cb;
>  	struct mutex cb_lock;
>  	u32 addr;
>  	void *priv;
> @@ -106,6 +109,7 @@ struct rpmsg_endpoint {
>   * @probe: invoked when a matching rpmsg channel (i.e. device) is found
>   * @remove: invoked when the rpmsg channel is removed
>   * @callback: invoked when an inbound message is received on the channel
> + * @flowcontrol: invoked when remote side flow control status is received
>   */
>  struct rpmsg_driver {
>  	struct device_driver drv;
> @@ -113,6 +117,7 @@ struct rpmsg_driver {
>  	int (*probe)(struct rpmsg_device *dev);
>  	void (*remove)(struct rpmsg_device *dev);
>  	int (*callback)(struct rpmsg_device *, void *, int, void *, u32);
> +	int (*flowcontrol)(struct rpmsg_device *, void *, bool);
>  };
>  
>  static inline u16 rpmsg16_to_cpu(struct rpmsg_device *rpdev, __rpmsg16 val)
> @@ -192,6 +197,8 @@ __poll_t rpmsg_poll(struct rpmsg_endpoint *ept, struct file *filp,
>  
>  ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept);
>  
> +int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable);
> +
>  #else
>  
>  static inline int rpmsg_register_device_override(struct rpmsg_device *rpdev,
> @@ -316,6 +323,14 @@ static inline ssize_t rpmsg_get_mtu(struct rpmsg_endpoint *ept)
>  	return -ENXIO;
>  }
>  
> +static inline int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
> +{
> +	/* This shouldn't be possible */
> +	WARN_ON(1);
> +
> +	return -ENXIO;
> +}
> +
>  #endif /* IS_ENABLED(CONFIG_RPMSG) */
>  
>  /* use a macro to avoid include chaining to get THIS_MODULE */
> diff --git a/include/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
> index 1637e68..c549649 100644
> --- a/include/uapi/linux/rpmsg.h
> +++ b/include/uapi/linux/rpmsg.h
> @@ -10,7 +10,7 @@
>  #include <linux/types.h>
>  
>  #define RPMSG_ADDR_ANY		0xFFFFFFFF
> -
> +#define RPMSG_FLOW_CONTROL_ON	0x001
>  /**
>   * struct rpmsg_endpoint_info - endpoint info representation
>   * @name: name of service
> @@ -43,4 +43,14 @@ struct rpmsg_endpoint_info {
>   */
>  #define RPMSG_RELEASE_DEV_IOCTL	_IOW(0xb5, 0x4, struct rpmsg_endpoint_info)
>  
> +/**
> + * Get the remote rpmsg char device's flow control signal.
> + */
> +#define RPMSG_GET_SIGNAL_IOCTL _IOW(0xb5, 0x5, struct rpmsg_endpoint_info)
> +
> +/**
> + * Set the flow control for the local rpmsg char device.
> + */
> +#define RPMSG_SET_SIGNAL_IOCTL _IOW(0xb5, 0x6, struct rpmsg_endpoint_info)
> +
>  #endif

Re: [PATCH V5 0/3] rpmsg signaling/flowcontrol patches

[Bjorn Andersson]

On Tue, 18 Apr 2023 14:18:38 +0530, Sarannya S wrote:
> Added new IOCTLS- RPMSG_GET_SIGNAL_IOCTL and RPMSG_SET_SIGNAL_IOCTL
> to get/set the rpmsg char device's flow control signal.
> Update the cmd name 'RPM_CMD_SIGNALS' to 'GLINK_CMD_SIGNALS'.
> Addressed review comments to change variable names/descriptions.
> 
> Chris Lew (2):
>   rpmsg: glink: Add support to handle signals command
>   rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support
> 
> [...]

Applied, thanks!

[1/3] rpmsg: core: Add signal API support
      commit: cc7c3bc62c6c74c217ea73e30a135fd2c3affb34
[2/3] rpmsg: glink: Add support to handle signals command
      commit: 96a7a78517751f01c2a3aeef46768159aca370fd
[3/3] rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support
      commit: bdae2e497fd6cb1de0f142f3c64d89a38e3576e3

Best regards,
-- 
Bjorn Andersson <andersson@kernel.org>

[PATCH V5 0/3] rpmsg signaling/flowcontrol patches

[Sarannya S]

Added two new RPMSG IOCTLs for rpmsg_char- RPMSG_GET_SIGNAL_IOCTRL and
RPMSG_SET_SIGNAL_IOCTRL, to set/get the flow.
Addressed review comments for changing variable names/ desciptions.

Sarannya S (3):
  rpmsg: core: Add signal API support
  rpmsg: glink: Add support to handle signals command
  rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support

 drivers/rpmsg/qcom_glink_native.c | 63 +++++++++++++++++++++++++++++++++++++++
 drivers/rpmsg/rpmsg_char.c        | 58 ++++++++++++++++++++++++++++++-----
 drivers/rpmsg/rpmsg_core.c        | 20 +++++++++++++
 drivers/rpmsg/rpmsg_internal.h    |  2 ++
 include/linux/rpmsg.h             | 15 ++++++++++
 include/uapi/linux/rpmsg.h        | 12 +++++++-
 6 files changed, 162 insertions(+), 8 deletions(-)

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH V5 1/3] rpmsg: core: Add signal API support

[Sarannya S]

Some transports like Glink support the state notifications between
clients using flow control signals similar to serial protocol signals.
Local glink client drivers can send and receive flow control status
to glink clients running on remote processors.

Add APIs to support sending and receiving of flow control status by
rpmsg clients.

Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
---
 drivers/rpmsg/rpmsg_core.c     | 20 ++++++++++++++++++++
 drivers/rpmsg/rpmsg_internal.h |  2 ++
 2 files changed, 22 insertions(+)

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index d6dde00e..e96967a 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -331,6 +331,24 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
 /**
+ * rpmsg_set_flow_control() - sets/clears serial flow control signals
+ * @ept:	the rpmsg endpoint
+ * @enable:	pause/resume incoming data flow
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->set_flow_control)
+		return -ENXIO;
+
+	return ept->ops->set_flow_control(ept, enable);
+}
+EXPORT_SYMBOL(rpmsg_set_flow_control);
+
+/**
  * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
  * @ept: the rpmsg endpoint
  *
@@ -539,6 +557,8 @@ static int rpmsg_dev_probe(struct device *dev)
 
 		rpdev->ept = ept;
 		rpdev->src = ept->addr;
+
+		ept->flow_cb = rpdrv->flowcontrol;
 	}
 
 	err = rpdrv->probe(rpdev);
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index 39b646d..4fea45a 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -55,6 +55,7 @@ struct rpmsg_device_ops {
  * @trysendto:		see @rpmsg_trysendto(), optional
  * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
  * @poll:		see @rpmsg_poll(), optional
+ * @set_flow_control:	see @rpmsg_set_flow_control(), optional
  * @get_mtu:		see @rpmsg_get_mtu(), optional
  *
  * Indirection table for the operations that a rpmsg backend should implement.
@@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops {
 			     void *data, int len);
 	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
 			     poll_table *wait);
+	int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable);
 	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
 };
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH V5 0/3] rpmsg signaling/flowcontrol patches

[Sarannya S]

Added two new RPMSG IOCTLs for rpmsg_char- RPMSG_GET_SIGNAL_IOCTRL and
RPMSG_SET_SIGNAL_IOCTRL, to set/get the flow.
Addressed review comments for changing variable names/ desciptions.

Sarannya S (3):
  rpmsg: core: Add signal API support
  rpmsg: glink: Add support to handle signals command
  rpmsg: char: Add RPMSG GET/SET SIGNAL IOCTL support

 drivers/rpmsg/qcom_glink_native.c | 63 +++++++++++++++++++++++++++++++++++++++
 drivers/rpmsg/rpmsg_char.c        | 58 ++++++++++++++++++++++++++++++-----
 drivers/rpmsg/rpmsg_core.c        | 20 +++++++++++++
 drivers/rpmsg/rpmsg_internal.h    |  2 ++
 include/linux/rpmsg.h             | 15 ++++++++++
 include/uapi/linux/rpmsg.h        | 12 +++++++-
 6 files changed, 162 insertions(+), 8 deletions(-)

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH V5 1/3] rpmsg: core: Add signal API support

[Sarannya S]

Some transports like Glink support the state notifications between
clients using flow control signals similar to serial protocol signals.
Local glink client drivers can send and receive flow control status
to glink clients running on remote processors.

Add APIs to support sending and receiving of flow control status by
rpmsg clients.

Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
---
 drivers/rpmsg/rpmsg_core.c     | 20 ++++++++++++++++++++
 drivers/rpmsg/rpmsg_internal.h |  2 ++
 2 files changed, 22 insertions(+)

diff --git a/drivers/rpmsg/rpmsg_core.c b/drivers/rpmsg/rpmsg_core.c
index d6dde00e..e96967a 100644
--- a/drivers/rpmsg/rpmsg_core.c
+++ b/drivers/rpmsg/rpmsg_core.c
@@ -331,6 +331,24 @@ int rpmsg_trysend_offchannel(struct rpmsg_endpoint *ept, u32 src, u32 dst,
 EXPORT_SYMBOL(rpmsg_trysend_offchannel);
 
 /**
+ * rpmsg_set_flow_control() - sets/clears serial flow control signals
+ * @ept:	the rpmsg endpoint
+ * @enable:	pause/resume incoming data flow
+ *
+ * Return: 0 on success and an appropriate error value on failure.
+ */
+int rpmsg_set_flow_control(struct rpmsg_endpoint *ept, bool enable)
+{
+	if (WARN_ON(!ept))
+		return -EINVAL;
+	if (!ept->ops->set_flow_control)
+		return -ENXIO;
+
+	return ept->ops->set_flow_control(ept, enable);
+}
+EXPORT_SYMBOL(rpmsg_set_flow_control);
+
+/**
  * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
  * @ept: the rpmsg endpoint
  *
@@ -539,6 +557,8 @@ static int rpmsg_dev_probe(struct device *dev)
 
 		rpdev->ept = ept;
 		rpdev->src = ept->addr;
+
+		ept->flow_cb = rpdrv->flowcontrol;
 	}
 
 	err = rpdrv->probe(rpdev);
diff --git a/drivers/rpmsg/rpmsg_internal.h b/drivers/rpmsg/rpmsg_internal.h
index 39b646d..4fea45a 100644
--- a/drivers/rpmsg/rpmsg_internal.h
+++ b/drivers/rpmsg/rpmsg_internal.h
@@ -55,6 +55,7 @@ struct rpmsg_device_ops {
  * @trysendto:		see @rpmsg_trysendto(), optional
  * @trysend_offchannel:	see @rpmsg_trysend_offchannel(), optional
  * @poll:		see @rpmsg_poll(), optional
+ * @set_flow_control:	see @rpmsg_set_flow_control(), optional
  * @get_mtu:		see @rpmsg_get_mtu(), optional
  *
  * Indirection table for the operations that a rpmsg backend should implement.
@@ -75,6 +76,7 @@ struct rpmsg_endpoint_ops {
 			     void *data, int len);
 	__poll_t (*poll)(struct rpmsg_endpoint *ept, struct file *filp,
 			     poll_table *wait);
+	int (*set_flow_control)(struct rpmsg_endpoint *ept, bool enable);
 	ssize_t (*get_mtu)(struct rpmsg_endpoint *ept);
 };
 
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

[PATCH V5 0/3] rpmsg signaling/flowcontrol patches

[Sarannya S]

Added two new RPMSG IOCTLs for rpmsg_char- RPMSG_GET_SIGNAL_IOCTRL and
RPMSG_SET_SIGNAL_IOCTRL, to set/get the flow.
Addressed review comments for changing variable names/ desciptions.

Sarannya S (3):
  rpmsg: core: Add signal API support
  rpmsg: glink: Add support to handle signals command
  rpmsg: char: Add TIOCMGET/TIOCMSET ioctl support

 arch/arm64/boot/Image.gz-dtb      | Bin 0 -> 12413735 bytes
 drivers/rpmsg/qcom_glink_native.c |  63 ++++++++++++++++++++++++++++++++++++++
 drivers/rpmsg/rpmsg_char.c        |  60 +++++++++++++++++++++++++++++++-----
 drivers/rpmsg/rpmsg_core.c        |  20 ++++++++++++
 drivers/rpmsg/rpmsg_core.c.rej    |  11 +++++++
 drivers/rpmsg/rpmsg_internal.h    |   2 ++
 include/linux/rpmsg.h             |  15 +++++++++
 include/uapi/linux/rpmsg.h        |  11 +++++++
 8 files changed, 174 insertions(+), 8 deletions(-)
 create mode 100644 arch/arm64/boot/Image.gz-dtb
 create mode 100644 drivers/rpmsg/rpmsg_core.c.rej

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH V5 1/3] rpmsg: core: Add signal API support

[Bjorn Andersson]

On Tue, Feb 21, 2023 at 08:05:12PM +0530, Sarannya S wrote:
> Some transports like Glink support the state notifications between
> clients using flow control signals similar to serial protocol signals.
> Local glink client drivers can send and receive flow control status
> to glink clients running on remote processors.
> 
> Add APIs to support sending and receiving of flow control status by
> rpmsg clients.
> 
> Signed-off-by: Deepak Kumar Singh <quic_deesin@quicinc.com>
> Signed-off-by: Sarannya S <quic_sarannya@quicinc.com>
> ---
>  arch/arm64/boot/Image.gz-dtb   | Bin 0 -> 12413735 bytes
>  drivers/rpmsg/rpmsg_core.c     |  20 ++++++++++++++++++++
>  drivers/rpmsg/rpmsg_core.c.rej |  11 +++++++++++
>  drivers/rpmsg/rpmsg_internal.h |   2 ++
>  include/linux/rpmsg.h          |  15 +++++++++++++++

Looks like you accidentally included the Image.gz-dtb and .rej file in
the patch. Please resend without these.

Thanks,
Bjorn

>  5 files changed, 48 insertions(+)
>  create mode 100644 arch/arm64/boot/Image.gz-dtb
>  create mode 100644 drivers/rpmsg/rpmsg_core.c.rej