diff mbox series

[net-next,v2,5/9] ptp: Add .getmaxphase callback to ptp_clock_info

Message ID 20230523205440.326934-6-rrameshbabu@nvidia.com (mailing list archive)
State Changes Requested
Delegated to: Netdev Maintainers
Headers show
Series ptp .adjphase cleanups | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 201 this patch: 201
netdev/cc_maintainers warning 1 maintainers not CCed: linux-kselftest@vger.kernel.org
netdev/build_clang success Errors and warnings before: 17 this patch: 17
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 236 this patch: 236
netdev/checkpatch warning CHECK: Comparison to NULL could be written "ptp->info->adjphase" CHECK: Comparison to NULL could be written "ptp->info->getmaxphase"
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Rahul Rameshbabu May 23, 2023, 8:54 p.m. UTC
Enables advertisement of the maximum offset supported by the phase control
functionality of PHCs. The callback is used to return an error if an offset
not supported by the PHC is used in ADJ_OFFSET. The ioctls
PTP_CLOCK_GETCAPS and PTP_CLOCK_GETCAPS2 now advertise the maximum offset a
PHC's phase control functionality is capable of supporting. Introduce new
sysfs node, max_phase_adjustment.

Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Maciek Machnikowski <maciek@machnikowski.net>
Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>
---

Notes:
    Changes:
    
      v2->v1:
        * Removes a macro introduced in v1 for adding PTP sysfs device
          attribute nodes using a callback for populating the data.

 drivers/ptp/ptp_chardev.c             |  5 ++++-
 drivers/ptp/ptp_clock.c               |  4 ++++
 drivers/ptp/ptp_sysfs.c               | 12 ++++++++++++
 include/linux/ptp_clock_kernel.h      |  5 +++++
 include/uapi/linux/ptp_clock.h        |  3 ++-
 tools/testing/selftests/ptp/testptp.c |  6 ++++--
 6 files changed, 31 insertions(+), 4 deletions(-)

Comments

Richard Cochran May 24, 2023, 3:43 a.m. UTC | #1
On Tue, May 23, 2023 at 01:54:36PM -0700, Rahul Rameshbabu wrote:
> Enables advertisement of the maximum offset supported by the phase control
> functionality of PHCs. The callback is used to return an error if an offset
> not supported by the PHC is used in ADJ_OFFSET. The ioctls
> PTP_CLOCK_GETCAPS and PTP_CLOCK_GETCAPS2 now advertise the maximum offset a
> PHC's phase control functionality is capable of supporting. Introduce new
> sysfs node, max_phase_adjustment.
> 
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Shuah Khan <shuah@kernel.org>
> Cc: Richard Cochran <richardcochran@gmail.com>
> Cc: Maciek Machnikowski <maciek@machnikowski.net>
> Signed-off-by: Rahul Rameshbabu <rrameshbabu@nvidia.com>

Acked-by: Richard Cochran <richardcochran@gmail.com>
diff mbox series

Patch

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index af3bc65c4595..362bf756e6b7 100644
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -136,7 +136,10 @@  long ptp_ioctl(struct posix_clock *pc, unsigned int cmd, unsigned long arg)
 		caps.pps = ptp->info->pps;
 		caps.n_pins = ptp->info->n_pins;
 		caps.cross_timestamping = ptp->info->getcrosststamp != NULL;
-		caps.adjust_phase = ptp->info->adjphase != NULL;
+		caps.adjust_phase = ptp->info->adjphase != NULL &&
+				    ptp->info->getmaxphase != NULL;
+		if (caps.adjust_phase)
+			caps.max_phase_adj = ptp->info->getmaxphase(ptp->info);
 		if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
 			err = -EFAULT;
 		break;
diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index 790f9250b381..80f74e38c2da 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -135,11 +135,15 @@  static int ptp_clock_adjtime(struct posix_clock *pc, struct __kernel_timex *tx)
 		ptp->dialed_frequency = tx->freq;
 	} else if (tx->modes & ADJ_OFFSET) {
 		if (ops->adjphase) {
+			s32 max_phase_adj = ops->getmaxphase(ops);
 			s32 offset = tx->offset;
 
 			if (!(tx->modes & ADJ_NANO))
 				offset *= NSEC_PER_USEC;
 
+			if (offset > max_phase_adj || offset < -max_phase_adj)
+				return -ERANGE;
+
 			err = ops->adjphase(ops, offset);
 		}
 	} else if (tx->modes == 0) {
diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index f30b0a439470..77219cdcd683 100644
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c
@@ -18,6 +18,17 @@  static ssize_t clock_name_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(clock_name);
 
+static ssize_t max_phase_adjustment_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *page)
+{
+	struct ptp_clock *ptp = dev_get_drvdata(dev);
+
+	return snprintf(page, PAGE_SIZE - 1, "%d\n",
+			ptp->info->getmaxphase(ptp->info));
+}
+static DEVICE_ATTR_RO(max_phase_adjustment);
+
 #define PTP_SHOW_INT(name, var)						\
 static ssize_t var##_show(struct device *dev,				\
 			   struct device_attribute *attr, char *page)	\
@@ -309,6 +320,7 @@  static struct attribute *ptp_attrs[] = {
 	&dev_attr_clock_name.attr,
 
 	&dev_attr_max_adjustment.attr,
+	&dev_attr_max_phase_adjustment.attr,
 	&dev_attr_n_alarms.attr,
 	&dev_attr_n_external_timestamps.attr,
 	&dev_attr_n_periodic_outputs.attr,
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
index f8e8443a8b35..1ef4e0f9bd2a 100644
--- a/include/linux/ptp_clock_kernel.h
+++ b/include/linux/ptp_clock_kernel.h
@@ -82,6 +82,10 @@  struct ptp_system_timestamp {
  *             parameter delta: PHC servo phase adjustment target
  *                              in nanoseconds.
  *
+ * @getmaxphase:  Advertises maximum offset that can be provided
+ *                to the hardware clock's phase control functionality
+ *                through adjphase.
+ *
  * @adjtime:  Shifts the time of the hardware clock.
  *            parameter delta: Desired change in nanoseconds.
  *
@@ -171,6 +175,7 @@  struct ptp_clock_info {
 	struct ptp_pin_desc *pin_config;
 	int (*adjfine)(struct ptp_clock_info *ptp, long scaled_ppm);
 	int (*adjphase)(struct ptp_clock_info *ptp, s32 phase);
+	s32 (*getmaxphase)(struct ptp_clock_info *ptp);
 	int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
 	int (*gettime64)(struct ptp_clock_info *ptp, struct timespec64 *ts);
 	int (*gettimex64)(struct ptp_clock_info *ptp, struct timespec64 *ts,
diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index 1d108d597f66..05cc35fc94ac 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -95,7 +95,8 @@  struct ptp_clock_caps {
 	int cross_timestamping;
 	/* Whether the clock supports adjust phase */
 	int adjust_phase;
-	int rsv[12];   /* Reserved for future use. */
+	int max_phase_adj; /* Maximum phase adjustment in nanoseconds. */
+	int rsv[11];       /* Reserved for future use. */
 };
 
 struct ptp_extts_request {
diff --git a/tools/testing/selftests/ptp/testptp.c b/tools/testing/selftests/ptp/testptp.c
index ae23ef51f198..a162a3e15c29 100644
--- a/tools/testing/selftests/ptp/testptp.c
+++ b/tools/testing/selftests/ptp/testptp.c
@@ -292,7 +292,8 @@  int main(int argc, char *argv[])
 			       "  %d pulse per second\n"
 			       "  %d programmable pins\n"
 			       "  %d cross timestamping\n"
-			       "  %d adjust_phase\n",
+			       "  %d adjust_phase\n"
+			       "  %d maximum phase adjustment (ns)\n",
 			       caps.max_adj,
 			       caps.n_alarm,
 			       caps.n_ext_ts,
@@ -300,7 +301,8 @@  int main(int argc, char *argv[])
 			       caps.pps,
 			       caps.n_pins,
 			       caps.cross_timestamping,
-			       caps.adjust_phase);
+			       caps.adjust_phase,
+			       caps.max_phase_adj);
 		}
 	}