From 5e196d34a776420278e4117b4742cd9d3f2350ed Mon Sep 17 00:00:00 2001 From: Alexander Gordeev Date: Wed, 12 Jan 2011 17:00:51 -0800 Subject: pps: access pps device by direct pointer Using device index as a pointer needs some unnecessary work to be done every time the pointer is needed (in irq handler for example). Using a direct pointer is much more easy (and safe as well). Signed-off-by: Alexander Gordeev Acked-by: Rodolfo Giometti Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/pps/kapi.c | 124 ++++++++++++----------------------------------------- 1 file changed, 28 insertions(+), 96 deletions(-) (limited to 'drivers/pps/kapi.c') diff --git a/drivers/pps/kapi.c b/drivers/pps/kapi.c index b431d83b824a..98d4012ca595 100644 --- a/drivers/pps/kapi.c +++ b/drivers/pps/kapi.c @@ -32,11 +32,11 @@ #include /* - * Global variables + * Local variables */ -DEFINE_SPINLOCK(pps_idr_lock); -DEFINE_IDR(pps_idr); +static DEFINE_SPINLOCK(pps_idr_lock); +static DEFINE_IDR(pps_idr); /* * Local functions @@ -60,60 +60,6 @@ static void pps_add_offset(struct pps_ktime *ts, struct pps_ktime *offset) * Exported functions */ -/* pps_get_source - find a PPS source - * @source: the PPS source ID. - * - * This function is used to find an already registered PPS source into the - * system. - * - * The function returns NULL if found nothing, otherwise it returns a pointer - * to the PPS source data struct (the refcounter is incremented by 1). - */ - -struct pps_device *pps_get_source(int source) -{ - struct pps_device *pps; - unsigned long flags; - - spin_lock_irqsave(&pps_idr_lock, flags); - - pps = idr_find(&pps_idr, source); - if (pps != NULL) - atomic_inc(&pps->usage); - - spin_unlock_irqrestore(&pps_idr_lock, flags); - - return pps; -} - -/* pps_put_source - free the PPS source data - * @pps: a pointer to the PPS source. - * - * This function is used to free a PPS data struct if its refcount is 0. - */ - -void pps_put_source(struct pps_device *pps) -{ - unsigned long flags; - - spin_lock_irqsave(&pps_idr_lock, flags); - BUG_ON(atomic_read(&pps->usage) == 0); - - if (!atomic_dec_and_test(&pps->usage)) { - pps = NULL; - goto exit; - } - - /* No more reference to the PPS source. We can safely remove the - * PPS data struct. - */ - idr_remove(&pps_idr, pps->id); - -exit: - spin_unlock_irqrestore(&pps_idr_lock, flags); - kfree(pps); -} - /* pps_register_source - add a PPS source in the system * @info: the PPS info struct * @default_params: the default PPS parameters of the new source @@ -122,10 +68,11 @@ exit: * source is described by info's fields and it will have, as default PPS * parameters, the ones specified into default_params. * - * The function returns, in case of success, the PPS source ID. + * The function returns, in case of success, the PPS device. Otherwise NULL. */ -int pps_register_source(struct pps_source_info *info, int default_params) +struct pps_device *pps_register_source(struct pps_source_info *info, + int default_params) { struct pps_device *pps; int id; @@ -168,7 +115,6 @@ int pps_register_source(struct pps_source_info *info, int default_params) init_waitqueue_head(&pps->queue); spin_lock_init(&pps->lock); - atomic_set(&pps->usage, 1); /* Get new ID for the new PPS source */ if (idr_pre_get(&pps_idr, GFP_KERNEL) == 0) { @@ -211,7 +157,7 @@ int pps_register_source(struct pps_source_info *info, int default_params) pr_info("new PPS source %s at ID %d\n", info->name, id); - return id; + return pps; free_idr: spin_lock_irq(&pps_idr_lock); @@ -224,38 +170,33 @@ kfree_pps: pps_register_source_exit: printk(KERN_ERR "pps: %s: unable to register source\n", info->name); - return err; + return NULL; } EXPORT_SYMBOL(pps_register_source); /* pps_unregister_source - remove a PPS source from the system - * @source: the PPS source ID + * @pps: the PPS source * * This function is used to remove a previously registered PPS source from * the system. */ -void pps_unregister_source(int source) +void pps_unregister_source(struct pps_device *pps) { - struct pps_device *pps; + unsigned int id = pps->id; - spin_lock_irq(&pps_idr_lock); - pps = idr_find(&pps_idr, source); + pps_unregister_cdev(pps); - if (!pps) { - BUG(); - spin_unlock_irq(&pps_idr_lock); - return; - } + spin_lock_irq(&pps_idr_lock); + idr_remove(&pps_idr, pps->id); spin_unlock_irq(&pps_idr_lock); - pps_unregister_cdev(pps); - pps_put_source(pps); + kfree(pps); } EXPORT_SYMBOL(pps_unregister_source); /* pps_event - register a PPS event into the system - * @source: the PPS source ID + * @pps: the PPS device * @ts: the event timestamp * @event: the event type * @data: userdef pointer @@ -263,30 +204,24 @@ EXPORT_SYMBOL(pps_unregister_source); * This function is used by each PPS client in order to register a new * PPS event into the system (it's usually called inside an IRQ handler). * - * If an echo function is associated with the PPS source it will be called + * If an echo function is associated with the PPS device it will be called * as: - * pps->info.echo(source, event, data); + * pps->info.echo(pps, event, data); */ - -void pps_event(int source, struct pps_event_time *ts, int event, void *data) +void pps_event(struct pps_device *pps, struct pps_event_time *ts, int event, + void *data) { - struct pps_device *pps; unsigned long flags; int captured = 0; struct pps_ktime ts_real; if ((event & (PPS_CAPTUREASSERT | PPS_CAPTURECLEAR)) == 0) { - printk(KERN_ERR "pps: unknown event (%x) for source %d\n", - event, source); + dev_err(pps->dev, "unknown event (%x)\n", event); return; } - pps = pps_get_source(source); - if (!pps) - return; - - pr_debug("PPS event on source %d at %ld.%09ld\n", - pps->id, ts->ts_real.tv_sec, ts->ts_real.tv_nsec); + dev_dbg(pps->dev, "PPS event at %ld.%09ld\n", + ts->ts_real.tv_sec, ts->ts_real.tv_nsec); timespec_to_pps_ktime(&ts_real, ts->ts_real); @@ -294,7 +229,7 @@ void pps_event(int source, struct pps_event_time *ts, int event, void *data) /* Must call the echo function? */ if ((pps->params.mode & (PPS_ECHOASSERT | PPS_ECHOCLEAR))) - pps->info.echo(source, event, data); + pps->info.echo(pps, event, data); /* Check the event */ pps->current_mode = pps->params.mode; @@ -308,8 +243,8 @@ void pps_event(int source, struct pps_event_time *ts, int event, void *data) /* Save the time stamp */ pps->assert_tu = ts_real; pps->assert_sequence++; - pr_debug("capture assert seq #%u for source %d\n", - pps->assert_sequence, source); + dev_dbg(pps->dev, "capture assert seq #%u\n", + pps->assert_sequence); captured = ~0; } @@ -323,8 +258,8 @@ void pps_event(int source, struct pps_event_time *ts, int event, void *data) /* Save the time stamp */ pps->clear_tu = ts_real; pps->clear_sequence++; - pr_debug("capture clear seq #%u for source %d\n", - pps->clear_sequence, source); + dev_dbg(pps->dev, "capture clear seq #%u\n", + pps->clear_sequence); captured = ~0; } @@ -338,8 +273,5 @@ void pps_event(int source, struct pps_event_time *ts, int event, void *data) } spin_unlock_irqrestore(&pps->lock, flags); - - /* Now we can release the PPS source for (possible) deregistration */ - pps_put_source(pps); } EXPORT_SYMBOL(pps_event); -- cgit v1.2.3