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>
diff --git a/include/linux/ptp_clock_kernel.h b/include/linux/ptp_clock_kernel.h
index 38a9935..0d8ff3f 100644
--- a/include/linux/ptp_clock_kernel.h
+++ b/include/linux/ptp_clock_kernel.h
@@ -49,7 +49,11 @@
* @n_alarm: The number of programmable alarms.
* @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.
* @pps: Indicates whether the clock supports a PPS callback.
+ * @pin_config: Array of length 'n_pins'. If the number of
+ * programmable pins is nonzero, then drivers must
+ * allocate and initialize this array.
*
* clock operations
*
@@ -70,6 +74,18 @@
* parameter request: Desired resource to enable or disable.
* parameter on: Caller passes one to enable or zero to disable.
*
+ * @verify: Confirm that a pin can perform a given function. The PTP
+ * Hardware Clock subsystem maintains the 'pin_config'
+ * array on behalf of the drivers, but the PHC subsystem
+ * assumes that every pin can perform every function. This
+ * hook gives drivers a way of telling the core about
+ * limitations on specific pins. This function must return
+ * zero if the function can be assigned to this pin, and
+ * nonzero otherwise.
+ * parameter pin: index of the pin in question.
+ * parameter func: the desired function to use.
+ * parameter chan: the function channel index to use.
+ *
* Drivers should embed their ptp_clock_info within a private
* structure, obtaining a reference to it using container_of().
*
@@ -83,13 +99,17 @@
int n_alarm;
int n_ext_ts;
int n_per_out;
+ int n_pins;
int pps;
+ struct ptp_pin_desc *pin_config;
int (*adjfreq)(struct ptp_clock_info *ptp, s32 delta);
int (*adjtime)(struct ptp_clock_info *ptp, s64 delta);
int (*gettime)(struct ptp_clock_info *ptp, struct timespec *ts);
int (*settime)(struct ptp_clock_info *ptp, const struct timespec *ts);
int (*enable)(struct ptp_clock_info *ptp,
struct ptp_clock_request *request, int on);
+ int (*verify)(struct ptp_clock_info *ptp, unsigned int pin,
+ enum ptp_pin_function func, unsigned int chan);
};
struct ptp_clock;
@@ -156,4 +176,17 @@
extern int ptp_clock_index(struct ptp_clock *ptp);
+/**
+ * ptp_find_pin() - obtain the pin index of a given auxiliary function
+ *
+ * @ptp: The clock obtained from ptp_clock_register().
+ * @func: One of the ptp_pin_function enumerated values.
+ * @chan: The particular functional channel to find.
+ * Return: Pin index in the range of zero to ptp_clock_caps.n_pins - 1,
+ * or -1 if the auxiliary function cannot be found.
+ */
+
+int ptp_find_pin(struct ptp_clock *ptp,
+ enum ptp_pin_function func, unsigned int chan);
+
#endif
diff --git a/include/uapi/linux/ptp_clock.h b/include/uapi/linux/ptp_clock.h
index b65c834..f0b7bfe 100644
--- a/include/uapi/linux/ptp_clock.h
+++ b/include/uapi/linux/ptp_clock.h
@@ -50,7 +50,8 @@
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_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 @@
#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. */