diff --git a/drivers/input/djoystick.c b/drivers/input/djoystick.c index 5e614d6cc1..ce114fe0aa 100644 --- a/drivers/input/djoystick.c +++ b/drivers/input/djoystick.c @@ -64,7 +64,6 @@ struct djoy_upperhalf_s FAR const struct djoy_lowerhalf_s *du_lower; djoy_buttonset_t du_sample; /* Last sampled button states */ - sem_t du_exclsem; /* Supports exclusive access to the device */ /* The following is a singly linked list of open references to the * joystick device. @@ -81,10 +80,6 @@ struct djoy_open_s FAR struct djoy_open_s *do_flink; - /* The following will be true if we are closing */ - - volatile bool do_closing; - /* Joystick event notification information */ pid_t do_pid; @@ -107,11 +102,6 @@ struct djoy_open_s * Private Function Prototypes ****************************************************************************/ -/* Semaphore helpers */ - -static inline int djoy_takesem(sem_t *sem); -#define djoy_givesem(s) nxsem_post(s); - /* Sampling and Interrupt handling */ static void djoy_enable(FAR struct djoy_upperhalf_s *priv); @@ -155,15 +145,6 @@ static const struct file_operations djoy_fops = * Private Functions ****************************************************************************/ -/**************************************************************************** - * Name: djoy_takesem - ****************************************************************************/ - -static inline int djoy_takesem(sem_t *sem) -{ - return nxsem_wait(sem); -} - /**************************************************************************** * Name: djoy_enable ****************************************************************************/ @@ -174,18 +155,11 @@ static void djoy_enable(FAR struct djoy_upperhalf_s *priv) FAR struct djoy_open_s *opriv; djoy_buttonset_t press; djoy_buttonset_t release; - irqstate_t flags; DEBUGASSERT(priv); lower = priv->du_lower; DEBUGASSERT(lower); - /* This routine is called both task level and interrupt level, so - * interrupts must be disabled. - */ - - flags = enter_critical_section(); - /* Visit each opened reference to the device */ press = 0; @@ -218,8 +192,6 @@ static void djoy_enable(FAR struct djoy_upperhalf_s *priv) lower->dl_enable(lower, 0, 0, NULL, NULL); } - - leave_critical_section(flags); } /**************************************************************************** @@ -336,38 +308,30 @@ static int djoy_open(FAR struct file *filep) FAR struct djoy_open_s *opriv; FAR const struct djoy_lowerhalf_s *lower; djoy_buttonset_t supported; - int ret; + irqstate_t flags; DEBUGASSERT(filep && filep->f_inode); inode = filep->f_inode; DEBUGASSERT(inode->i_private); priv = (FAR struct djoy_upperhalf_s *)inode->i_private; - /* Get exclusive access to the driver structure */ - - ret = djoy_takesem(&priv->du_exclsem); - if (ret < 0) - { - ierr("ERROR: djoy_takesem failed: %d\n", ret); - return ret; - } - /* Allocate a new open structure */ opriv = (FAR struct djoy_open_s *)kmm_zalloc(sizeof(struct djoy_open_s)); if (!opriv) { ierr("ERROR: Failed to allocate open structure\n"); - ret = -ENOMEM; - goto errout_with_sem; + return -ENOMEM; } /* Initialize the open structure */ lower = priv->du_lower; DEBUGASSERT(lower && lower->dl_supported); - supported = lower->dl_supported(lower); + flags = enter_critical_section(); + + supported = lower->dl_supported(lower); opriv->do_pollevents.dp_press = supported; opriv->do_pollevents.dp_release = supported; @@ -383,11 +347,9 @@ static int djoy_open(FAR struct file *filep) /* Attach the open structure to the file structure */ filep->f_priv = (FAR void *)opriv; - ret = OK; -errout_with_sem: - djoy_givesem(&priv->du_exclsem); - return ret; + leave_critical_section(flags); + return OK; } /**************************************************************************** @@ -402,8 +364,6 @@ static int djoy_close(FAR struct file *filep) FAR struct djoy_open_s *curr; FAR struct djoy_open_s *prev; irqstate_t flags; - bool closing; - int ret; DEBUGASSERT(filep && filep->f_priv && filep->f_inode); opriv = filep->f_priv; @@ -411,36 +371,7 @@ static int djoy_close(FAR struct file *filep) DEBUGASSERT(inode->i_private); priv = (FAR struct djoy_upperhalf_s *)inode->i_private; - /* Handle an improbable race conditions with the following atomic test - * and set. - * - * This is actually a pretty feeble attempt to handle this. The - * improbable race condition occurs if two different threads try to - * close the joystick driver at the same time. The rule: don't do - * that! It is feeble because we do not really enforce stale pointer - * detection anyway. - */ - flags = enter_critical_section(); - closing = opriv->do_closing; - opriv->do_closing = true; - leave_critical_section(flags); - - if (closing) - { - /* Another thread is doing the close */ - - return OK; - } - - /* Get exclusive access to the driver structure */ - - ret = djoy_takesem(&priv->du_exclsem); - if (ret < 0) - { - ierr("ERROR: djoy_takesem failed: %d\n", ret); - return ret; - } /* Find the open structure in the list of open structures for the device */ @@ -452,8 +383,8 @@ static int djoy_close(FAR struct file *filep) if (!curr) { ierr("ERROR: Failed to find open entry\n"); - ret = -ENOENT; - goto errout_with_exclsem; + leave_critical_section(flags); + return -ENOENT; } /* Remove the structure from the device */ @@ -467,6 +398,12 @@ static int djoy_close(FAR struct file *filep) priv->du_open = opriv->do_flink; } + /* Enable/disable interrupt handling */ + + djoy_enable(priv); + + leave_critical_section(flags); + /* Cancel any pending notification */ nxsig_cancel_notification(&opriv->do_work); @@ -474,15 +411,7 @@ static int djoy_close(FAR struct file *filep) /* And free the open structure */ kmm_free(opriv); - - /* Enable/disable interrupt handling */ - - djoy_enable(priv); - ret = OK; - -errout_with_exclsem: - djoy_givesem(&priv->du_exclsem); - return ret; + return OK; } /**************************************************************************** @@ -496,6 +425,7 @@ static ssize_t djoy_read(FAR struct file *filep, FAR char *buffer, FAR struct djoy_open_s *opriv; FAR struct djoy_upperhalf_s *priv; FAR const struct djoy_lowerhalf_s *lower; + irqstate_t flags; int ret; DEBUGASSERT(filep && filep->f_inode); @@ -516,12 +446,7 @@ static ssize_t djoy_read(FAR struct file *filep, FAR char *buffer, /* Get exclusive access to the driver structure */ - ret = djoy_takesem(&priv->du_exclsem); - if (ret < 0) - { - ierr("ERROR: djoy_takesem failed: %d\n", ret); - return ret; - } + flags = enter_critical_section(); /* Read and return the current state of the joystick buttons */ @@ -532,7 +457,7 @@ static ssize_t djoy_read(FAR struct file *filep, FAR char *buffer, opriv->do_pollpending = false; ret = sizeof(djoy_buttonset_t); - djoy_givesem(&priv->du_exclsem); + leave_critical_section(flags); return (ssize_t)ret; } @@ -546,6 +471,7 @@ static int djoy_ioctl(FAR struct file *filep, int cmd, unsigned long arg) FAR struct djoy_upperhalf_s *priv; FAR struct djoy_open_s *opriv; FAR const struct djoy_lowerhalf_s *lower; + irqstate_t flags; int ret; DEBUGASSERT(filep && filep->f_priv && filep->f_inode); @@ -556,12 +482,7 @@ static int djoy_ioctl(FAR struct file *filep, int cmd, unsigned long arg) /* Get exclusive access to the driver structure */ - ret = djoy_takesem(&priv->du_exclsem); - if (ret < 0) - { - ierr("ERROR: djoy_takesem failed: %d\n", ret); - return ret; - } + flags = enter_critical_section(); /* Handle the ioctl command */ @@ -661,7 +582,7 @@ static int djoy_ioctl(FAR struct file *filep, int cmd, unsigned long arg) break; } - djoy_givesem(&priv->du_exclsem); + leave_critical_section(flags); return ret; } @@ -673,25 +594,19 @@ static int djoy_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup) { FAR struct inode *inode; - FAR struct djoy_upperhalf_s *priv; FAR struct djoy_open_s *opriv; - int ret; + irqstate_t flags; + int ret = OK; int i; DEBUGASSERT(filep && filep->f_priv && filep->f_inode); opriv = filep->f_priv; inode = filep->f_inode; DEBUGASSERT(inode->i_private); - priv = (FAR struct djoy_upperhalf_s *)inode->i_private; /* Get exclusive access to the driver structure */ - ret = djoy_takesem(&priv->du_exclsem); - if (ret < 0) - { - ierr("ERROR: djoy_takesem failed: %d\n", ret); - return ret; - } + flags = enter_critical_section(); /* Are we setting up the poll? Or tearing it down? */ @@ -731,7 +646,7 @@ static int djoy_poll(FAR struct file *filep, FAR struct pollfd *fds, ierr("ERROR: Too man poll waiters\n"); fds->priv = NULL; ret = -EBUSY; - goto errout_with_dusem; + goto errout; } } else if (fds->priv) @@ -745,7 +660,7 @@ static int djoy_poll(FAR struct file *filep, FAR struct pollfd *fds, { ierr("ERROR: Poll slot not found\n"); ret = -EIO; - goto errout_with_dusem; + goto errout; } #endif @@ -755,8 +670,8 @@ static int djoy_poll(FAR struct file *filep, FAR struct pollfd *fds, fds->priv = NULL; } -errout_with_dusem: - djoy_givesem(&priv->du_exclsem); +errout: + leave_critical_section(flags); return ret; } @@ -797,7 +712,6 @@ int djoy_register(FAR const char *devname, priv = (FAR struct djoy_upperhalf_s *) kmm_zalloc(sizeof(struct djoy_upperhalf_s)); - if (!priv) { ierr("ERROR: Failed to allocate device structure\n"); @@ -812,7 +726,6 @@ int djoy_register(FAR const char *devname, /* Initialize the new djoystick driver instance */ priv->du_lower = lower; - nxsem_init(&priv->du_exclsem, 0, 1); DEBUGASSERT(lower->dl_sample); priv->du_sample = lower->dl_sample(lower); @@ -823,7 +736,6 @@ int djoy_register(FAR const char *devname, if (ret < 0) { ierr("ERROR: register_driver failed: %d\n", ret); - nxsem_destroy(&priv->du_exclsem); kmm_free(priv); }