From: Dmitry Torokhov <dtor_core@ameritech.net>
> 3) They light up a led on the keyboard,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
atkbd tries to switch leds but one tasklet can not interrupt another so
it deadlocks...
You need to revert just the patch below, not entire bk-input
---
25-akpm/drivers/input/serio/i8042.c | 140 ++++++++++++------------------------
1 files changed, 49 insertions(+), 91 deletions(-)
diff -puN drivers/input/serio/i8042.c~revert-i8042-interrupt-handling drivers/input/serio/i8042.c
--- 25/drivers/input/serio/i8042.c~revert-i8042-interrupt-handling 2004-05-13 17:09:59.987912912 -0700
+++ 25-akpm/drivers/input/serio/i8042.c 2004-05-13 17:10:47.710657952 -0700
@@ -2,7 +2,6 @@
* i8042 keyboard and mouse controller driver for Linux
*
* Copyright (c) 1999-2002 Vojtech Pavlik
- * Copyright (c) 2004 Dmitry Torokhov
*/
/*
@@ -75,14 +74,6 @@ struct i8042_values {
unsigned char *phys;
};
-#define I8042_QUEUE_LEN 64
-struct {
- unsigned char str[I8042_QUEUE_LEN];
- unsigned char data[I8042_QUEUE_LEN];
- unsigned int read_pos;
- unsigned int write_pos;
-} i8042_buf;
-
static struct serio i8042_kbd_port;
static struct serio i8042_aux_port;
static unsigned char i8042_initial_ctr;
@@ -91,7 +82,7 @@ static unsigned char i8042_mux_open;
static unsigned char i8042_mux_present;
static unsigned char i8042_sysdev_initialized;
static struct pm_dev *i8042_pm_dev;
-static struct timer_list i8042_timer;
+struct timer_list i8042_timer;
/*
* Shared IRQ's require a device pointer, but this driver doesn't support
@@ -383,108 +374,76 @@ static char i8042_mux_short[4][16];
static char i8042_mux_phys[4][32];
/*
- * i8042_handle_data() is the most important function in this driver -
- * it processes data received by i8042_interrupt and sends it to the
- * upper layers.
+ * i8042_interrupt() is the most important function in this driver -
+ * it handles the interrupts from the i8042, and sends incoming bytes
+ * to the upper layers.
*/
-static void i8042_handle_data(unsigned long notused)
+static irqreturn_t i8042_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
+ unsigned long flags;
unsigned char str, data = 0;
unsigned int dfl;
+ int ret;
- /*
- * No locking it required on i8042_buf as the tasklet is guaranteed
- * to be serialized and if write_pos changes while comparing it with
- * read_pos another run will be scheduled by i8042_interrupt.
- */
- while (i8042_buf.read_pos != i8042_buf.write_pos) {
-
- str = i8042_buf.str[i8042_buf.read_pos];
- data = i8042_buf.data[i8042_buf.read_pos];
+ mod_timer(&i8042_timer, jiffies + I8042_POLL_PERIOD);
- i8042_buf.read_pos++;
- i8042_buf.read_pos %= I8042_QUEUE_LEN;
+ spin_lock_irqsave(&i8042_lock, flags);
+ str = i8042_read_status();
+ if (str & I8042_STR_OBF)
+ data = i8042_read_data();
+ spin_unlock_irqrestore(&i8042_lock, flags);
- dfl = ((str & I8042_STR_PARITY) ? SERIO_PARITY : 0) |
- ((str & I8042_STR_TIMEOUT) ? SERIO_TIMEOUT : 0);
-
- if (i8042_mux_values[0].exists && (str & I8042_STR_AUXDATA)) {
-
- if (str & I8042_STR_MUXERR) {
- switch (data) {
- case 0xfd:
- case 0xfe: dfl = SERIO_TIMEOUT; break;
- case 0xff: dfl = SERIO_PARITY; break;
- }
- data = 0xfe;
- } else dfl = 0;
-
- dbg("%02x <- i8042 (interrupt, aux%d, %d%s%s)",
- data, (str >> 6), irq,
- dfl & SERIO_PARITY ? ", bad parity" : "",
- dfl & SERIO_TIMEOUT ? ", timeout" : "");
-
- serio_interrupt(i8042_mux_port + ((str >> 6) & 3), data, dfl, NULL);
- } else {
-
- dbg("%02x <- i8042 (interrupt, %s, %d%s%s)",
- data, (str & I8042_STR_AUXDATA) ? "aux" : "kbd", irq,
- dfl & SERIO_PARITY ? ", bad parity" : "",
- dfl & SERIO_TIMEOUT ? ", timeout" : "");
-
- if (i8042_aux_values.exists && (str & I8042_STR_AUXDATA))
- serio_interrupt(&i8042_aux_port, data, dfl, NULL);
- else if (i8042_kbd_values.exists)
- serio_interrupt(&i8042_kbd_port, data, dfl, NULL);
- }
+ if (~str & I8042_STR_OBF) {
+ if (irq) dbg("Interrupt %d, without any data", irq);
+ ret = 0;
+ goto out;
}
-}
-DECLARE_TASKLET(i8042_tasklet, i8042_handle_data, 0);
+ dfl = ((str & I8042_STR_PARITY) ? SERIO_PARITY : 0) |
+ ((str & I8042_STR_TIMEOUT) ? SERIO_TIMEOUT : 0);
-/*
- * i8042_interrupt() handles the interrupts from i8042 and schedules
- * i8042_handle_data to process and pass received bytes to the upper
- * layers.
- */
+ if (i8042_mux_values[0].exists && (str & I8042_STR_AUXDATA)) {
-static irqreturn_t i8042_interrupt(int irq, void *dev_id, struct pt_regs *regs)
-{
- unsigned long flags;
- unsigned char str;
- unsigned int n_bytes = 0;
-
- mod_timer(&i8042_timer, jiffies + I8042_POLL_PERIOD);
-
- spin_lock_irqsave(&i8042_lock, flags);
-
- while ((str = i8042_read_status()) & I8042_STR_OBF) {
-
- n_bytes++;
+ if (str & I8042_STR_MUXERR) {
+ switch (data) {
+ case 0xfd:
+ case 0xfe: dfl = SERIO_TIMEOUT; break;
+ case 0xff: dfl = SERIO_PARITY; break;
+ }
+ data = 0xfe;
+ } else dfl = 0;
- i8042_buf.str[i8042_buf.write_pos] = str;
- i8042_buf.data[i8042_buf.write_pos] = i8042_read_data();
+ dbg("%02x <- i8042 (interrupt, aux%d, %d%s%s)",
+ data, (str >> 6), irq,
+ dfl & SERIO_PARITY ? ", bad parity" : "",
+ dfl & SERIO_TIMEOUT ? ", timeout" : "");
- i8042_buf.write_pos++;
- i8042_buf.write_pos %= I8042_QUEUE_LEN;
+ serio_interrupt(i8042_mux_port + ((str >> 6) & 3), data, dfl, regs);
- if (unlikely(i8042_buf.write_pos == i8042_buf.read_pos))
- printk(KERN_WARNING "i8042.c: ring buffer full\n");
+ goto irq_ret;
}
- spin_unlock_irqrestore(&i8042_lock, flags);
+ dbg("%02x <- i8042 (interrupt, %s, %d%s%s)",
+ data, (str & I8042_STR_AUXDATA) ? "aux" : "kbd", irq,
+ dfl & SERIO_PARITY ? ", bad parity" : "",
+ dfl & SERIO_TIMEOUT ? ", timeout" : "");
- if (unlikely(n_bytes == 0)) {
- if (irq) dbg("Interrupt %d, without any data", irq);
- return IRQ_NONE;
+ if (i8042_aux_values.exists && (str & I8042_STR_AUXDATA)) {
+ serio_interrupt(&i8042_aux_port, data, dfl, regs);
+ goto irq_ret;
}
- tasklet_schedule(&i8042_tasklet);
+ if (!i8042_kbd_values.exists)
+ goto irq_ret;
- return IRQ_HANDLED;
-}
+ serio_interrupt(&i8042_kbd_port, data, dfl, regs);
+irq_ret:
+ ret = 1;
+out:
+ return IRQ_RETVAL(ret);
+}
/*
* i8042_enable_mux_mode checks whether the controller has an active
@@ -1060,7 +1019,6 @@ void __exit i8042_exit(void)
serio_unregister_port(i8042_mux_port + i);
del_timer_sync(&i8042_timer);
- tasklet_kill(&i8042_tasklet);
i8042_platform_exit();
}
_