Char: serial167, remove bottomhalf

- Cy_EVENT_OPEN_WAKEUP is simple wake_up
- Cy_EVENT_HANGUP is wake_up + tty_hangup, which schedules its own work
- Cy_EVENT_WRITE_WAKEUP is tty_wakeup which may be called directly too

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Acked-by: Alan Cox <alan@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 68 deletions

diff --git a/drivers/char/serial167.c b/drivers/char/serial167.c
index cbf21cc7b56d..df8cd0ca97eb 100644
--- a/drivers/char/serial167.c
+++ b/drivers/char/serial167.c
@@ -357,18 +357,6 @@ static void cy_start(struct tty_struct *tty)
         local_irq_restore(flags);
 }                               /* cy_start */
 
-/*
- * This routine is used by the interrupt handler to schedule
- * processing in the software interrupt portion of the driver
- * (also known as the "bottom half").  This can be called any
- * number of times for any channel without harm.
- */
-static inline void cy_sched_event(struct cyclades_port *info, int event)
-{
-        info->event |= 1 << event;      /* remember what kind of event and who */
-        schedule_work(&info->tqueue);
-}                               /* cy_sched_event */
-
 /* The real interrupt service routines are called
    whenever the card wants its hand held--chars
    received, out buffer empty, modem change, etc.
@@ -483,10 +471,12 @@ static irqreturn_t cd2401_modem_interrupt(int irq, void *dev_id)
                     && (info->flags & ASYNC_CHECK_CD)) {
                         if (mdm_status & CyDCD) {
 /* CP('!'); */
-                                cy_sched_event(info, Cy_EVENT_OPEN_WAKEUP);
+                                wake_up_interruptible(&info->open_wait);
                         } else {
 /* CP('@'); */
-                                cy_sched_event(info, Cy_EVENT_HANGUP);
+                                tty_hangup(info->tty);
+                                wake_up_interruptible(&info->open_wait);
+                                info->flags &= ~ASYNC_NORMAL_ACTIVE;
                         }
                 }
                 if ((mdm_change & CyCTS)
@@ -496,8 +486,7 @@ static irqreturn_t cd2401_modem_interrupt(int irq, void *dev_id)
                                         /* !!! cy_start isn't used because... */
                                         info->tty->stopped = 0;
                                         base_addr[CyIER] |= CyTxMpty;
-                                        cy_sched_event(info,
-                                                       Cy_EVENT_WRITE_WAKEUP);
+                                        tty_wakeup(info->tty);
                                 }
                         } else {
                                 if (!(mdm_status & CyCTS)) {
@@ -543,9 +532,6 @@ static irqreturn_t cd2401_tx_interrupt(int irq, void *dev_id)
         info->last_active = jiffies;
         if (info->tty == 0) {
                 base_addr[CyIER] &= ~(CyTxMpty | CyTxRdy);
-                if (info->xmit_cnt < WAKEUP_CHARS) {
-                        cy_sched_event(info, Cy_EVENT_WRITE_WAKEUP);
-                }
                 base_addr[CyTEOIR] = CyNOTRANS;
                 return IRQ_HANDLED;
         }
@@ -627,9 +613,9 @@ static irqreturn_t cd2401_tx_interrupt(int irq, void *dev_id)
                 }
         }
 
-        if (info->xmit_cnt < WAKEUP_CHARS) {
-                cy_sched_event(info, Cy_EVENT_WRITE_WAKEUP);
-        }
+        if (info->xmit_cnt < WAKEUP_CHARS)
+                tty_wakeup(info->tty);
+
         base_addr[CyTEOIR] = (char_count != saved_cnt) ? 0 : CyNOTRANS;
         return IRQ_HANDLED;
 }                               /* cy_tx_interrupt */
@@ -690,49 +676,6 @@ static irqreturn_t cd2401_rx_interrupt(int irq, void *dev_id)
         return IRQ_HANDLED;
 }                               /* cy_rx_interrupt */
 
-/*
- * This routine is used to handle the "bottom half" processing for the
- * serial driver, known also the "software interrupt" processing.
- * This processing is done at the kernel interrupt level, after the
- * cy#/_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
- * is where time-consuming activities which can not be done in the
- * interrupt driver proper are done; the interrupt driver schedules
- * them using cy_sched_event(), and they get done here.
- *
- * This is done through one level of indirection--the task queue.
- * When a hardware interrupt service routine wants service by the
- * driver's bottom half, it enqueues the appropriate tq_struct (one
- * per port) to the keventd work queue and sets a request flag
- * that the work queue be processed.
- *
- * Although this may seem unwieldy, it gives the system a way to
- * pass an argument (in this case the pointer to the cyclades_port
- * structure) to the bottom half of the driver.  Previous kernels
- * had to poll every port to see if that port needed servicing.
- */
-static void do_softint(struct work_struct *ugly_api)
-{
-        struct cyclades_port *info =
-            container_of(ugly_api, struct cyclades_port, tqueue);
-        struct tty_struct *tty;
-
-        tty = info->tty;
-        if (!tty)
-                return;
-
-        if (test_and_clear_bit(Cy_EVENT_HANGUP, &info->event)) {
-                tty_hangup(info->tty);
-                wake_up_interruptible(&info->open_wait);
-                info->flags &= ~ASYNC_NORMAL_ACTIVE;
-        }
-        if (test_and_clear_bit(Cy_EVENT_OPEN_WAKEUP, &info->event)) {
-                wake_up_interruptible(&info->open_wait);
-        }
-        if (test_and_clear_bit(Cy_EVENT_WRITE_WAKEUP, &info->event)) {
-                tty_wakeup(tty);
-        }
-}                               /* do_softint */
-
 /* This is called whenever a port becomes active;
    interrupts are enabled and DTR & RTS are turned on.
  */
@@ -1743,7 +1686,6 @@ static void cy_close(struct tty_struct *tty, struct file *filp)
         if (tty->driver->flush_buffer)
                 tty->driver->flush_buffer(tty);
         tty_ldisc_flush(tty);
-        info->event = 0;
         info->tty = NULL;
         if (info->blocked_open) {
                 if (info->close_delay) {
@@ -2234,7 +2176,6 @@ static int __init serial167_init(void)
                                 info->rco = baud_co[DefSpeed] >> 5;     /* Rx CO */
                                 info->close_delay = 0;
                                 info->x_char = 0;
-                                info->event = 0;
                                 info->count = 0;
 #ifdef SERIAL_DEBUG_COUNT
                                 printk("cyc: %d: setting count to 0\n",
@@ -2243,7 +2184,6 @@ static int __init serial167_init(void)
                                 info->blocked_open = 0;
                                 info->default_threshold = 0;
                                 info->default_timeout = 0;
-                                INIT_WORK(&info->tqueue, do_softint);
                                 init_waitqueue_head(&info->open_wait);
                                 init_waitqueue_head(&info->close_wait);
                                 /* info->session */