ptp: introduce programmable pins.

This patch adds a pair of new ioctls to the PTP Hardware Clock device
interface. Using the ioctls, user space programs can query each pin to
find out its current function and also reprogram a different function
if desired.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 38 insertions, 1 deletions

diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index b65c834f83e9..f0b7bfe5da92 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -50,7 +50,8 @@ struct ptp_clock_caps {
         int n_ext_ts;  /* Number of external time stamp channels. */
         int n_per_out; /* Number of programmable periodic signals. */
         int pps;       /* Whether the clock supports a PPS callback. */
-        int rsv[15];   /* Reserved for future use. */
+        int n_pins;    /* Number of input/output pins. */
+        int rsv[14];   /* Reserved for future use. */
 };
 
 struct ptp_extts_request {
@@ -80,6 +81,40 @@ struct ptp_sys_offset {
         struct ptp_clock_time ts[2 * PTP_MAX_SAMPLES + 1];
 };
 
+enum ptp_pin_function {
+        PTP_PF_NONE,
+        PTP_PF_EXTTS,
+        PTP_PF_PEROUT,
+        PTP_PF_PHYSYNC,
+};
+
+struct ptp_pin_desc {
+        /*
+         * Hardware specific human readable pin name. This field is
+         * set by the kernel during the PTP_PIN_GETFUNC ioctl and is
+         * ignored for the PTP_PIN_SETFUNC ioctl.
+         */
+        char name[64];
+        /*
+         * Pin index in the range of zero to ptp_clock_caps.n_pins - 1.
+         */
+        unsigned int index;
+        /*
+         * Which of the PTP_PF_xxx functions to use on this pin.
+         */
+        unsigned int func;
+        /*
+         * The specific channel to use for this function.
+         * This corresponds to the 'index' field of the
+         * PTP_EXTTS_REQUEST and PTP_PEROUT_REQUEST ioctls.
+         */
+        unsigned int chan;
+        /*
+         * Reserved for future use.
+         */
+        unsigned int rsv[5];
+};
+
 #define PTP_CLK_MAGIC '='
 
 #define PTP_CLOCK_GETCAPS  _IOR(PTP_CLK_MAGIC, 1, struct ptp_clock_caps)
@@ -87,6 +122,8 @@ struct ptp_sys_offset {
 #define PTP_PEROUT_REQUEST _IOW(PTP_CLK_MAGIC, 3, struct ptp_perout_request)
 #define PTP_ENABLE_PPS     _IOW(PTP_CLK_MAGIC, 4, int)
 #define PTP_SYS_OFFSET     _IOW(PTP_CLK_MAGIC, 5, struct ptp_sys_offset)
+#define PTP_PIN_GETFUNC    _IOWR(PTP_CLK_MAGIC, 6, struct ptp_pin_desc)
+#define PTP_PIN_SETFUNC    _IOW(PTP_CLK_MAGIC, 7, struct ptp_pin_desc)
 
 struct ptp_extts_event {
         struct ptp_clock_time t; /* Time event occured. */