From a2d818030135c293f878fbb772cf40e7a14c5acc Mon Sep 17 00:00:00 2001 From: "Robert P. J. Day" Date: Fri, 8 Sep 2017 16:17:19 -0700 Subject: [PATCH] drivers/pps: aesthetic tweaks to PPS-related content Collection of aesthetic adjustments to various PPS-related files, directories and Documentation, some quite minor just for the sake of consistency, including: * Updated example of pps device tree node (courtesy Rodolfo G.) * "PPS-API" -> "PPS API" * "pps_source_info_s" -> "pps_source_info" * "ktimer driver" -> "pps-ktimer driver" * "ppstest /dev/pps0" -> "ppstest /dev/pps1" to match example * Add missing PPS-related entries to MAINTAINERS file * Other trivialities Link: http://lkml.kernel.org/r/alpine.LFD.2.20.1708261048220.8106@localhost.localdomain Signed-off-by: Robert P. J. Day Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- .../devicetree/bindings/pps/pps-gpio.txt | 8 +++- Documentation/pps/pps.txt | 44 ++++++++++--------- MAINTAINERS | 3 ++ include/linux/pps-gpio.h | 2 +- include/linux/pps_kernel.h | 16 +++---- include/uapi/linux/pps.h | 4 +- kernel/time/timekeeping.c | 2 +- 7 files changed, 43 insertions(+), 36 deletions(-) diff --git a/Documentation/devicetree/bindings/pps/pps-gpio.txt b/Documentation/devicetree/bindings/pps/pps-gpio.txt index 40bf9c3564a5..0de23b793657 100644 --- a/Documentation/devicetree/bindings/pps/pps-gpio.txt +++ b/Documentation/devicetree/bindings/pps/pps-gpio.txt @@ -13,8 +13,12 @@ Optional properties: Example: pps { - compatible = "pps-gpio"; - gpios = <&gpio2 6 0>; + pinctrl-names = "default"; + pinctrl-0 = <&pinctrl_pps>; + gpios = <&gpio1 26 GPIO_ACTIVE_HIGH>; assert-falling-edge; + + compatible = "pps-gpio"; + status = "okay"; }; diff --git a/Documentation/pps/pps.txt b/Documentation/pps/pps.txt index 1fdbd5447216..99f5d8c4c652 100644 --- a/Documentation/pps/pps.txt +++ b/Documentation/pps/pps.txt @@ -48,12 +48,12 @@ problem: time_pps_create(). This implies that the source has a /dev/... entry. This assumption is -ok for the serial and parallel port, where you can do something +OK for the serial and parallel port, where you can do something useful besides(!) the gathering of timestamps as it is the central -task for a PPS-API. But this assumption does not work for a single +task for a PPS API. But this assumption does not work for a single purpose GPIO line. In this case even basic file-related functionality (like read() and write()) makes no sense at all and should not be a -precondition for the use of a PPS-API. +precondition for the use of a PPS API. The problem can be simply solved if you consider that a PPS source is not always connected with a GPS data source. @@ -88,13 +88,13 @@ Coding example -------------- To register a PPS source into the kernel you should define a struct -pps_source_info_s as follows: +pps_source_info as follows: static struct pps_source_info pps_ktimer_info = { .name = "ktimer", .path = "", - .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | \ - PPS_ECHOASSERT | \ + .mode = PPS_CAPTUREASSERT | PPS_OFFSETASSERT | + PPS_ECHOASSERT | PPS_CANWAIT | PPS_TSFMT_TSPEC, .echo = pps_ktimer_echo, .owner = THIS_MODULE, @@ -108,13 +108,13 @@ initialization routine as follows: The pps_register_source() prototype is: - int pps_register_source(struct pps_source_info_s *info, int default_params) + int pps_register_source(struct pps_source_info *info, int default_params) where "info" is a pointer to a structure that describes a particular PPS source, "default_params" tells the system what the initial default parameters for the device should be (it is obvious that these parameters must be a subset of ones defined in the struct -pps_source_info_s which describe the capabilities of the driver). +pps_source_info which describe the capabilities of the driver). Once you have registered a new PPS source into the system you can signal an assert event (for example in the interrupt handler routine) @@ -142,8 +142,10 @@ If the SYSFS filesystem is enabled in the kernel it provides a new class: Every directory is the ID of a PPS sources defined in the system and inside you find several files: - $ ls /sys/class/pps/pps0/ - assert clear echo mode name path subsystem@ uevent + $ ls -F /sys/class/pps/pps0/ + assert dev mode path subsystem@ + clear echo name power/ uevent + Inside each "assert" and "clear" file you can find the timestamp and a sequence number: @@ -154,32 +156,32 @@ sequence number: Where before the "#" is the timestamp in seconds; after it is the sequence number. Other files are: -* echo: reports if the PPS source has an echo function or not; + * echo: reports if the PPS source has an echo function or not; -* mode: reports available PPS functioning modes; + * mode: reports available PPS functioning modes; -* name: reports the PPS source's name; + * name: reports the PPS source's name; -* path: reports the PPS source's device path, that is the device the - PPS source is connected to (if it exists). + * path: reports the PPS source's device path, that is the device the + PPS source is connected to (if it exists). Testing the PPS support ----------------------- In order to test the PPS support even without specific hardware you can use -the ktimer driver (see the client subsection in the PPS configuration menu) +the pps-ktimer driver (see the client subsection in the PPS configuration menu) and the userland tools available in your distribution's pps-tools package, -http://linuxpps.org , or https://github.com/ago/pps-tools . +http://linuxpps.org , or https://github.com/redlab-i/pps-tools. -Once you have enabled the compilation of ktimer just modprobe it (if +Once you have enabled the compilation of pps-ktimer just modprobe it (if not statically compiled): - # modprobe ktimer + # modprobe pps-ktimer and the run ppstest as follow: - $ ./ppstest /dev/pps0 + $ ./ppstest /dev/pps1 trying PPS source "/dev/pps1" found PPS source "/dev/pps1" ok, found 1 source(s), now start fetching data... @@ -187,7 +189,7 @@ and the run ppstest as follow: source 0 - assert 1186592700.388931295, sequence: 365 - clear 0.000000000, sequence: 0 source 0 - assert 1186592701.389032765, sequence: 366 - clear 0.000000000, sequence: 0 -Please, note that to compile userland programs you need the file timepps.h . +Please note that to compile userland programs, you need the file timepps.h. This is available in the pps-tools repository mentioned above. diff --git a/MAINTAINERS b/MAINTAINERS index ff3a349f24e4..109c5d9a04c4 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10725,8 +10725,11 @@ W: http://wiki.enneenne.com/index.php/LinuxPPS_support L: linuxpps@ml.enneenne.com (subscribers-only) S: Maintained F: Documentation/pps/ +F: Documentation/devicetree/bindings/pps/pps-gpio.txt +F: Documentation/ABI/testing/sysfs-pps F: drivers/pps/ F: include/linux/pps*.h +F: include/uapi/linux/pps.h PPTP DRIVER M: Dmitry Kozlov diff --git a/include/linux/pps-gpio.h b/include/linux/pps-gpio.h index 0035abe41b9a..56f35dd3d01d 100644 --- a/include/linux/pps-gpio.h +++ b/include/linux/pps-gpio.h @@ -29,4 +29,4 @@ struct pps_gpio_platform_data { const char *gpio_label; }; -#endif +#endif /* _PPS_GPIO_H */ diff --git a/include/linux/pps_kernel.h b/include/linux/pps_kernel.h index 35ac903956c7..80a980cc8d95 100644 --- a/include/linux/pps_kernel.h +++ b/include/linux/pps_kernel.h @@ -22,7 +22,6 @@ #define LINUX_PPS_KERNEL_H #include - #include #include #include @@ -35,9 +34,9 @@ struct pps_device; /* The specific PPS source info */ struct pps_source_info { - char name[PPS_MAX_NAME_LEN]; /* simbolic name */ + char name[PPS_MAX_NAME_LEN]; /* symbolic name */ char path[PPS_MAX_NAME_LEN]; /* path of connected device */ - int mode; /* PPS's allowed mode */ + int mode; /* PPS allowed mode */ void (*echo)(struct pps_device *pps, int event, void *data); /* PPS echo function */ @@ -57,10 +56,10 @@ struct pps_event_time { struct pps_device { struct pps_source_info info; /* PSS source info */ - struct pps_kparams params; /* PPS's current params */ + struct pps_kparams params; /* PPS current params */ - __u32 assert_sequence; /* PPS' assert event seq # */ - __u32 clear_sequence; /* PPS' clear event seq # */ + __u32 assert_sequence; /* PPS assert event seq # */ + __u32 clear_sequence; /* PPS clear event seq # */ struct pps_ktime assert_tu; struct pps_ktime clear_tu; int current_mode; /* PPS mode at event time */ @@ -69,7 +68,7 @@ struct pps_device { wait_queue_head_t queue; /* PPS event queue */ unsigned int id; /* PPS source unique ID */ - void const *lookup_cookie; /* pps_lookup_dev only */ + void const *lookup_cookie; /* For pps_lookup_dev() only */ struct cdev cdev; struct device *dev; struct fasync_struct *async_queue; /* fasync method */ @@ -101,7 +100,7 @@ extern struct pps_device *pps_register_source( extern void pps_unregister_source(struct pps_device *pps); extern void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event, void *data); -/* Look up a pps device by magic cookie */ +/* Look up a pps_device by magic cookie */ struct pps_device *pps_lookup_dev(void const *cookie); static inline void timespec_to_pps_ktime(struct pps_ktime *kt, @@ -132,4 +131,3 @@ static inline void pps_sub_ts(struct pps_event_time *ts, struct timespec64 delta } #endif /* LINUX_PPS_KERNEL_H */ - diff --git a/include/uapi/linux/pps.h b/include/uapi/linux/pps.h index c1cb3825a8bc..c29d6b791c08 100644 --- a/include/uapi/linux/pps.h +++ b/include/uapi/linux/pps.h @@ -95,8 +95,8 @@ struct pps_kparams { #define PPS_CAPTURECLEAR 0x02 /* capture clear events */ #define PPS_CAPTUREBOTH 0x03 /* capture assert and clear events */ -#define PPS_OFFSETASSERT 0x10 /* apply compensation for assert ev. */ -#define PPS_OFFSETCLEAR 0x20 /* apply compensation for clear ev. */ +#define PPS_OFFSETASSERT 0x10 /* apply compensation for assert event */ +#define PPS_OFFSETCLEAR 0x20 /* apply compensation for clear event */ #define PPS_CANWAIT 0x100 /* can we wait for an event? */ #define PPS_CANPOLL 0x200 /* bit reserved for future use */ diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 8ea4fb315719..2cafb49aa65e 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -2316,7 +2316,7 @@ void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts) raw_spin_unlock_irqrestore(&timekeeper_lock, flags); } EXPORT_SYMBOL(hardpps); -#endif +#endif /* CONFIG_NTP_PPS */ /** * xtime_update() - advances the timekeeping infrastructure -- 2.20.1