| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <20250827063332.1217664-5-wei.fang@nxp.com>
Date: Wed, 27 Aug 2025 14:33:19 +0800
From: Wei Fang <wei.fang@....com>
To: robh@...nel.org,
krzk+dt@...nel.org,
conor+dt@...nel.org,
richardcochran@...il.com,
claudiu.manoil@....com,
vladimir.oltean@....com,
xiaoning.wang@....com,
andrew+netdev@...n.ch,
davem@...emloft.net,
edumazet@...gle.com,
kuba@...nel.org,
pabeni@...hat.com,
vadim.fedorenko@...ux.dev,
Frank.Li@....com,
shawnguo@...nel.org
Cc: fushi.peng@....com,
devicetree@...r.kernel.org,
netdev@...r.kernel.org,
linux-kernel@...r.kernel.org,
imx@...ts.linux.dev
Subject: [PATCH v6 net-next 04/17] ptp: add debugfs interfaces to loop back the periodic output signal
For some PTP devices, they have the capability to loop back the periodic
output signal for debugging, such as the ptp_qoriq device. So add the
generic interfaces to set the periodic output signal loopback, rather
than each vendor having a different implementation.
Show how many channels support the periodic output signal loopback:
$ cat /sys/kernel/debug/ptp<N>/n_perout_loopback
Enable the loopback of the periodic output signal of channel X:
$ echo <X> 1 > /sys/kernel/debug/ptp<N>/perout_loopback
Disable the loopback of the periodic output signal of channel X:
$ echo <X> 0 > /sys/kernel/debug/ptp<N>/perout_loopback
Suggested-by: Andrew Lunn <andrew@...n.ch>
Signed-off-by: Wei Fang <wei.fang@....com>
---
v6 changes:
1. New patch
---
drivers/ptp/ptp_clock.c | 66 ++++++++++++++++++++++++++++++++
include/linux/ptp_clock_kernel.h | 10 +++++
2 files changed, 76 insertions(+)
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index 2b0fd62a17ef..0a45c5ebd904 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -237,6 +237,66 @@ static void ptp_aux_kworker(struct kthread_work *work)
kthread_queue_delayed_work(ptp->kworker, &ptp->aux_work, delay);
}
+static ssize_t ptp_n_perout_loopback_read(struct file *filep,
+ char __user *buffer,
+ size_t count, loff_t *pos)
+{
+ struct ptp_clock *ptp = filep->private_data;
+ char buf[12] = {};
+
+ snprintf(buf, sizeof(buf), "%d\n", ptp->info->n_per_lp);
+
+ return simple_read_from_buffer(buffer, count, pos, buf, strlen(buf));
+}
+
+static const struct file_operations ptp_n_perout_loopback_fops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .read = ptp_n_perout_loopback_read,
+};
+
+static ssize_t ptp_perout_loopback_write(struct file *filep,
+ const char __user *buffer,
+ size_t count, loff_t *ppos)
+{
+ struct ptp_clock *ptp = filep->private_data;
+ struct ptp_clock_info *ops = ptp->info;
+ int len, cnt, enable, err;
+ unsigned int index;
+ char buf[32] = {};
+
+ if (*ppos || !count)
+ return -EINVAL;
+
+ if (count >= sizeof(buf))
+ return -ENOSPC;
+
+ len = simple_write_to_buffer(buf, sizeof(buf) - 1,
+ ppos, buffer, count);
+ if (len < 0)
+ return len;
+
+ buf[len] = '\0';
+ cnt = sscanf(buf, "%u %d", &index, &enable);
+ if (cnt != 2)
+ return -EINVAL;
+
+ if (index >= ops->n_per_lp)
+ return -EINVAL;
+
+ err = ops->perout_loopback(ops, index, enable ? 1 : 0);
+ if (err)
+ return err;
+
+ return count;
+}
+
+static const struct file_operations ptp_perout_loopback_ops = {
+ .owner = THIS_MODULE,
+ .open = simple_open,
+ .write = ptp_perout_loopback_write,
+};
+
/* public interface */
struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
@@ -378,6 +438,12 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
/* Debugfs initialization */
snprintf(debugfsname, sizeof(debugfsname), "ptp%d", ptp->index);
ptp->debugfs_root = debugfs_create_dir(debugfsname, NULL);
+ if (info->n_per_lp > 0 && info->perout_loopback) {
+ debugfs_create_file("n_perout_loopback", 0400, ptp->debugfs_root,
+ ptp, &ptp_n_perout_loopback_fops);
+ debugfs_create_file("perout_loopback", 0200, ptp->debugfs_root,
+ ptp, &ptp_perout_loopback_ops);
+ }
return ptp;
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
index 7dd7951b23d5..884364596dd3 100644
--- a/include/linux/ptp_clock_kernel.h
+++ b/include/linux/ptp_clock_kernel.h
@@ -67,6 +67,8 @@ struct ptp_system_timestamp {
* @n_ext_ts: The number of external time stamp channels.
* @n_per_out: The number of programmable periodic signals.
* @n_pins: The number of programmable pins.
+ * @n_per_lp: The number of channels that support loopback the periodic
+ * output signal.
* @pps: Indicates whether the clock supports a PPS callback.
*
* @supported_perout_flags: The set of flags the driver supports for the
@@ -175,6 +177,11 @@ struct ptp_system_timestamp {
* scheduling time (>=0) or negative value in case further
* scheduling is not required.
*
+ * @perout_loopback: Request driver to enable or disable the periodic output
+ * signal loopback.
+ * parameter index: index of the periodic output signal channel.
+ * parameter on: caller passes one to enable or zero to disable.
+ *
* Drivers should embed their ptp_clock_info within a private
* structure, obtaining a reference to it using container_of().
*
@@ -189,6 +196,7 @@ struct ptp_clock_info {
int n_ext_ts;
int n_per_out;
int n_pins;
+ int n_per_lp;
int pps;
unsigned int supported_perout_flags;
unsigned int supported_extts_flags;
@@ -213,6 +221,8 @@ struct ptp_clock_info {
int (*verify)(struct ptp_clock_info *ptp, unsigned int pin,
enum ptp_pin_function func, unsigned int chan);
long (*do_aux_work)(struct ptp_clock_info *ptp);
+ int (*perout_loopback)(struct ptp_clock_info *ptp, unsigned int index,
+ int on);
};
struct ptp_clock;
--
2.34.1
Powered by blists - more mailing lists