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

[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

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

[Sarannya S]

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 115c0a1..01d0a49 100644
--- a/drivers/rpmsg/qcom_glink_native.c
+++ b/drivers/rpmsg/qcom_glink_native.c
@@ -17,6 +17,7 @@
 #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>
 
@@ -203,9 +204,15 @@ static const struct rpmsg_endpoint_ops glink_endpoint_ops;
 #define RPM_CMD_TX_DATA_CONT		12
 #define RPM_CMD_READ_NOTIF		13
 #define RPM_CMD_RX_DONE_W_REUSE		14
+#define RPM_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,
@@ -1001,6 +1008,57 @@ 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(RPM_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;
+}
+
 static irqreturn_t qcom_glink_native_intr(int irq, void *data)
 {
 	struct qcom_glink *glink = data;
@@ -1065,6 +1123,10 @@ static irqreturn_t qcom_glink_native_intr(int irq, void *data)
 			qcom_glink_handle_intent_req_ack(glink, param1, param2);
 			qcom_glink_rx_advance(glink, ALIGN(sizeof(msg), 8));
 			break;
+		case RPM_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;
@@ -1440,6 +1502,7 @@ 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 TIOCMGET/TIOCMSET ioctl support

[Sarannya S]

Add TICOMGET and TIOCMSET 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 | 60 +++++++++++++++++++++++++++++++++++++++-------
 include/uapi/linux/rpmsg.h | 11 +++++++++
 2 files changed, 63 insertions(+), 8 deletions(-)

diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
index 3e0b8f3..fdcb4ff 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)
@@ -109,7 +112,22 @@ 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;
@@ -146,6 +164,7 @@ 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);
@@ -166,6 +185,7 @@ 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);
@@ -279,6 +299,9 @@ 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;
+
 	mask |= rpmsg_poll(eptdev->ept, filp, wait);
 
 	return mask;
@@ -289,14 +312,35 @@ 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;
-
-	/* Don't allow to destroy a default endpoint. */
-	if (eptdev->default_ept)
-		return -EINVAL;
+	bool set;
+	u32 val;
+	int ret;
+	
+	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/uapi/linux/rpmsg.h b/include/uapi/linux/rpmsg.h
index 1637e68..e9aa6b9 100644
--- a/include/uapi/linux/rpmsg.h
+++ b/include/uapi/linux/rpmsg.h
@@ -10,6 +10,7 @@
 #include <linux/types.h>
 
 #define RPMSG_ADDR_ANY		0xFFFFFFFF
+#define RPMSG_FLOW_CONTROL_ON  0x001
 
 /**
  * struct rpmsg_endpoint_info - endpoint info representation
@@ -43,4 +44,14 @@ 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 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

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 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

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

[Konrad Dybcio]

On 21.02.2023 17:03, Sarannya S wrote:
> 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.
> 
Hi, your changes mostly don't apply on -next-20230228, please rebase
them. Not sure if I didn't miss anything, but I did it locally to test
this [1]. My Wi-Fi chip on SM6375 seems to send quite some signals calls
and applying this series got rid of "unhandled rx cmd: 15" and the
corresponding timeouts.

Also, please consider using b4 [2] for sending patches, you only sent
them to a couple of people and it didn't even reach patchwork..

Konrad

[1] https://github.com/SoMainline/linux/commits/signals_rebase
[2] https://b4.docs.kernel.org/en/latest/contributor/overview.html
> 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(-)
> 

[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 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