[PATCH v1 1/2] ptp: ptp_clock: make scaled_ppm_to_ppb static inline

Radu Pirea (NXP OSS)
2021-04-28T12:30:38Z

Make scaled_ppm_to_ppb static inline to be able to build drivers that
use this function even with PTP_1588_CLOCK disabled.

Signed-off-by: Radu Pirea (NXP OSS) <radu-nicolae.pirea@oss.nxp.com>
---
drivers/ptp/ptp_clock.c | 21 --------------------
include/linux/ptp_clock_kernel.h | 34 ++++++++++++++++++++++++--------
2 files changed, 26 insertions(+), 29 deletions(-)

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index 03a246e60fd9..a780435331c8 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -63,27 +63,6 @@ static void enqueue_external_timestamp(struct timestamp_event_queue *queue,
spin_unlock_irqrestore(&queue->lock, flags);
}

-s32 scaled_ppm_to_ppb(long ppm)
-{
- /*
- * The 'freq' field in the 'struct timex' is in parts per
- * million, but with a 16 bit binary fractional field.
- *
- * We want to calculate
- *
- * ppb = scaled_ppm * 1000 / 2^16
- *
- * which simplifies to
- *
- * ppb = scaled_ppm * 125 / 2^13
- */
- s64 ppb = 1 + ppm;
- ppb *= 125;
- ppb >>= 13;
- return (s32) ppb;
-}
-EXPORT_SYMBOL(scaled_ppm_to_ppb);
-
/* posix clock implementation */

static int ptp_clock_getres(struct posix_clock *pc, struct timespec64 *tp)
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
index 0d47fd33b228..a311bddd9e85 100644
--- a/include/linux/ptp_clock_kernel.h
+++ b/include/linux/ptp_clock_kernel.h
@@ -186,6 +186,32 @@ struct ptp_clock_event {
};
};

+/**
+ * scaled_ppm_to_ppb() - convert scaled ppm to ppb
+ *
+ * @ppm: Parts per million, but with a 16 bit binary fractional field
+ */
+static inline s32 scaled_ppm_to_ppb(long ppm)
+{
+ /*
+ * The 'freq' field in the 'struct timex' is in parts per
+ * million, but with a 16 bit binary fractional field.
+ *
+ * We want to calculate
+ *
+ * ppb = scaled_ppm * 1000 / 2^16
+ *
+ * which simplifies to
+ *
+ * ppb = scaled_ppm * 125 / 2^13
+ */
+ s64 ppb = 1 + ppm;
+
+ ppb *= 125;
+ ppb >>= 13;
+ return (s32)ppb;
+}
+
#if IS_REACHABLE(CONFIG_PTP_1588_CLOCK)

/**
@@ -229,14 +255,6 @@ extern void ptp_clock_event(struct ptp_clock *ptp,

extern int ptp_clock_index(struct ptp_clock *ptp);

-/**
- * scaled_ppm_to_ppb() - convert scaled ppm to ppb
- *
- * @ppm: Parts per million, but with a 16 bit binary fractional field
- */
-
-extern s32 scaled_ppm_to_ppb(long ppm);
-
/**
* ptp_find_pin() - obtain the pin index of a given auxiliary function
*
--
2.31.1