On Mon, 2003-07-07 at 09:03, Paul Mackerras wrote:
> This patch changes i2c-keywest.c to use mod_timer instead of a
> two-line sequence to compute .expires and call add_timer in 3 places.
> Without this patch I get a BUG from time to time in add_timer.
Ok, here it is. It also remove the never used "polled" mode. The
driver is now in sync with the more up-to-date 2.4 version ;)
Sorry for not sending that earlier, I forgot about it and didn't
notice it was out of sync.
Ben.
===== drivers/i2c/i2c-keywest.c 1.2 vs edited =====
--- 1.2/drivers/i2c/i2c-keywest.c Wed Apr 23 13:32:32 2003
+++ edited/drivers/i2c/i2c-keywest.c Tue Jul 8 12:16:51 2003
@@ -66,8 +66,6 @@
#include "i2c-keywest.h"
-#undef POLLED_MODE
-
#define DBG(x...) do {\
if (debug > 0) \
printk(KERN_DEBUG "KW:" x); \
@@ -85,27 +83,6 @@
static struct keywest_iface *ifaces = NULL;
-#ifdef POLLED_MODE
-/* This isn't fast, but will go once I implement interrupt with
- * proper timeout
- */
-static u8
-wait_interrupt(struct keywest_iface* iface)
-{
- int i;
- u8 isr;
-
- for (i = 0; i < POLL_TIMEOUT; i++) {
- isr = read_reg(reg_isr) & KW_I2C_IRQ_MASK;
- if (isr != 0)
- return isr;
- current->state = TASK_UNINTERRUPTIBLE;
- schedule_timeout(1);
- }
- return isr;
-}
-#endif /* POLLED_MODE */
-
static void
do_stop(struct keywest_iface* iface, int result)
@@ -116,16 +93,17 @@
}
/* Main state machine for standard & standard sub mode */
-static void
+static int
handle_interrupt(struct keywest_iface *iface, u8 isr)
{
int ack;
+ int rearm_timer = 1;
DBG("handle_interrupt(), got: %x, status: %x, state: %d\n",
isr, read_reg(reg_status), iface->state);
if (isr == 0 && iface->state != state_stop) {
do_stop(iface, -1);
- return;
+ return rearm_timer;
}
if (isr & KW_I2C_IRQ_STOP && iface->state != state_stop) {
iface->result = -1;
@@ -196,20 +174,19 @@
if (!(isr & KW_I2C_IRQ_STOP) && (++iface->stopretry) < 10)
do_stop(iface, -1);
else {
+ rearm_timer = 0;
iface->state = state_idle;
write_reg(reg_control, 0x00);
write_reg(reg_ier, 0x00);
-#ifndef POLLED_MODE
complete(&iface->complete);
-#endif /* POLLED_MODE */
}
break;
}
write_reg(reg_isr, isr);
-}
-#ifndef POLLED_MODE
+ return rearm_timer;
+}
/* Interrupt handler */
static irqreturn_t
@@ -219,8 +196,7 @@
spin_lock(&iface->lock);
del_timer(&iface->timeout_timer);
- handle_interrupt(iface, read_reg(reg_isr));
- if (iface->state != state_idle) {
+ if (handle_interrupt(iface, read_reg(reg_isr))) {
iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
add_timer(&iface->timeout_timer);
}
@@ -235,16 +211,13 @@
DBG("timeout !\n");
spin_lock_irq(&iface->lock);
- handle_interrupt(iface, read_reg(reg_isr));
- if (iface->state != state_idle) {
+ if (handle_interrupt(iface, read_reg(reg_isr))) {
iface->timeout_timer.expires = jiffies + POLL_TIMEOUT;
add_timer(&iface->timeout_timer);
}
spin_unlock(&iface->lock);
}
-#endif /* POLLED_MODE */
-
/*
* SMBUS-type transfer entrypoint
*/
@@ -338,17 +311,7 @@
write_reg(reg_control, read_reg(reg_control) | KW_I2C_CTL_XADDR);
write_reg(reg_ier, KW_I2C_IRQ_MASK);
-#ifdef POLLED_MODE
- DBG("using polled mode...\n");
- /* State machine, to turn into an interrupt handler */
- while(iface->state != state_idle) {
- u8 isr = wait_interrupt(iface);
- handle_interrupt(iface, isr);
- }
-#else /* POLLED_MODE */
- DBG("using interrupt mode...\n");
wait_for_completion(&iface->complete);
-#endif /* POLLED_MODE */
rc = iface->result;
DBG("transfer done, result: %d\n", rc);
@@ -428,17 +391,7 @@
write_reg(reg_control, read_reg(reg_control) | KW_I2C_CTL_XADDR);
write_reg(reg_ier, KW_I2C_IRQ_MASK);
-#ifdef POLLED_MODE
- DBG("using polled mode...\n");
- /* State machine, to turn into an interrupt handler */
- while(iface->state != state_idle) {
- u8 isr = wait_interrupt(iface);
- handle_interrupt(iface, isr);
- }
-#else /* POLLED_MODE */
- DBG("using interrupt mode...\n");
wait_for_completion(&iface->complete);
-#endif /* POLLED_MODE */
rc = iface->result;
if (rc == 0)
@@ -540,8 +493,8 @@
*prate);
}
- /* Select standard sub mode */
- iface->cur_mode |= KW_I2C_MODE_STANDARDSUB;
+ /* Select standard mode by default */
+ iface->cur_mode |= KW_I2C_MODE_STANDARD;
/* Write mode */
write_reg(reg_mode, iface->cur_mode);
@@ -550,7 +503,6 @@
write_reg(reg_ier, 0x00);
write_reg(reg_isr, KW_I2C_IRQ_MASK);
-#ifndef POLLED_MODE
/* Request chip interrupt */
rc = request_irq(iface->irq, keywest_irq, 0, "keywest i2c", iface);
if (rc) {
@@ -559,7 +511,6 @@
kfree(iface);
return -ENODEV;
}
-#endif /* POLLED_MODE */
for (i=0; i<nchan; i++) {
struct keywest_chan* chan = &iface->channels[i];
@@ -609,19 +560,16 @@
/* Make sure we stop all activity */
down(&iface->sem);
-#ifndef POLLED_MODE
spin_lock_irq(&iface->lock);
while (iface->state != state_idle) {
spin_unlock_irq(&iface->lock);
- schedule();
+ set_task_state(current,TASK_UNINTERRUPTIBLE);
+ schedule_timeout(HZ/10);
spin_lock_irq(&iface->lock);
}
-#endif /* POLLED_MODE */
iface->state = state_dead;
-#ifndef POLLED_MODE
spin_unlock_irq(&iface->lock);
free_irq(iface->irq, iface);
-#endif /* POLLED_MODE */
up(&iface->sem);
/* Release all channels */
-
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This archive was generated by hypermail 2b29 : Tue Jul 15 2003 - 22:00:26 EST