Root/
| 1 | /* |
| 2 | * PPS kernel consumer API |
| 3 | * |
| 4 | * Copyright (C) 2009-2010 Alexander Gordeev <lasaine@lvk.cs.msu.su> |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 19 | */ |
| 20 | |
| 21 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| 22 | |
| 23 | #include <linux/kernel.h> |
| 24 | #include <linux/module.h> |
| 25 | #include <linux/device.h> |
| 26 | #include <linux/init.h> |
| 27 | #include <linux/spinlock.h> |
| 28 | #include <linux/pps_kernel.h> |
| 29 | |
| 30 | #include "kc.h" |
| 31 | |
| 32 | /* |
| 33 | * Global variables |
| 34 | */ |
| 35 | |
| 36 | /* state variables to bind kernel consumer */ |
| 37 | DEFINE_SPINLOCK(pps_kc_hardpps_lock); |
| 38 | /* PPS API (RFC 2783): current source and mode for kernel consumer */ |
| 39 | struct pps_device *pps_kc_hardpps_dev; /* unique pointer to device */ |
| 40 | int pps_kc_hardpps_mode; /* mode bits for kernel consumer */ |
| 41 | |
| 42 | /* pps_kc_bind - control PPS kernel consumer binding |
| 43 | * @pps: the PPS source |
| 44 | * @bind_args: kernel consumer bind parameters |
| 45 | * |
| 46 | * This function is used to bind or unbind PPS kernel consumer according to |
| 47 | * supplied parameters. Should not be called in interrupt context. |
| 48 | */ |
| 49 | int pps_kc_bind(struct pps_device *pps, struct pps_bind_args *bind_args) |
| 50 | { |
| 51 | /* Check if another consumer is already bound */ |
| 52 | spin_lock_irq(&pps_kc_hardpps_lock); |
| 53 | |
| 54 | if (bind_args->edge == 0) |
| 55 | if (pps_kc_hardpps_dev == pps) { |
| 56 | pps_kc_hardpps_mode = 0; |
| 57 | pps_kc_hardpps_dev = NULL; |
| 58 | spin_unlock_irq(&pps_kc_hardpps_lock); |
| 59 | dev_info(pps->dev, "unbound kernel" |
| 60 | " consumer\n"); |
| 61 | } else { |
| 62 | spin_unlock_irq(&pps_kc_hardpps_lock); |
| 63 | dev_err(pps->dev, "selected kernel consumer" |
| 64 | " is not bound\n"); |
| 65 | return -EINVAL; |
| 66 | } |
| 67 | else |
| 68 | if (pps_kc_hardpps_dev == NULL || |
| 69 | pps_kc_hardpps_dev == pps) { |
| 70 | pps_kc_hardpps_mode = bind_args->edge; |
| 71 | pps_kc_hardpps_dev = pps; |
| 72 | spin_unlock_irq(&pps_kc_hardpps_lock); |
| 73 | dev_info(pps->dev, "bound kernel consumer: " |
| 74 | "edge=0x%x\n", bind_args->edge); |
| 75 | } else { |
| 76 | spin_unlock_irq(&pps_kc_hardpps_lock); |
| 77 | dev_err(pps->dev, "another kernel consumer" |
| 78 | " is already bound\n"); |
| 79 | return -EINVAL; |
| 80 | } |
| 81 | |
| 82 | return 0; |
| 83 | } |
| 84 | |
| 85 | /* pps_kc_remove - unbind kernel consumer on PPS source removal |
| 86 | * @pps: the PPS source |
| 87 | * |
| 88 | * This function is used to disable kernel consumer on PPS source removal |
| 89 | * if this source was bound to PPS kernel consumer. Can be called on any |
| 90 | * source safely. Should not be called in interrupt context. |
| 91 | */ |
| 92 | void pps_kc_remove(struct pps_device *pps) |
| 93 | { |
| 94 | spin_lock_irq(&pps_kc_hardpps_lock); |
| 95 | if (pps == pps_kc_hardpps_dev) { |
| 96 | pps_kc_hardpps_mode = 0; |
| 97 | pps_kc_hardpps_dev = NULL; |
| 98 | spin_unlock_irq(&pps_kc_hardpps_lock); |
| 99 | dev_info(pps->dev, "unbound kernel consumer" |
| 100 | " on device removal\n"); |
| 101 | } else |
| 102 | spin_unlock_irq(&pps_kc_hardpps_lock); |
| 103 | } |
| 104 | |
| 105 | /* pps_kc_event - call hardpps() on PPS event |
| 106 | * @pps: the PPS source |
| 107 | * @ts: PPS event timestamp |
| 108 | * @event: PPS event edge |
| 109 | * |
| 110 | * This function calls hardpps() when an event from bound PPS source occurs. |
| 111 | */ |
| 112 | void pps_kc_event(struct pps_device *pps, struct pps_event_time *ts, |
| 113 | int event) |
| 114 | { |
| 115 | unsigned long flags; |
| 116 | |
| 117 | /* Pass some events to kernel consumer if activated */ |
| 118 | spin_lock_irqsave(&pps_kc_hardpps_lock, flags); |
| 119 | if (pps == pps_kc_hardpps_dev && event & pps_kc_hardpps_mode) |
| 120 | hardpps(&ts->ts_real, &ts->ts_raw); |
| 121 | spin_unlock_irqrestore(&pps_kc_hardpps_lock, flags); |
| 122 | } |
| 123 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9
