On Mon, 17 Sep 2007 19:32:11 -0700 (PDT) Trent Piepho xyzzy@speakeasy.org wrote:
The polling loop to check for ACI to go down was more convoluted than it needed to be. New loop should be more efficient and it is a lot simpler. The old loop checked for a timeout before checking for ACI down, which could result in an erroneous timeout. It's only a failure if the timeout expires _and_ ACI is still high. There is nothing wrong with the timeout expiring while the task is sleeping if ACI went low.
This was already fixed by Rene's patch. You only simplified it.
A polling loop to check for the device to leaving INIT mode is removed. The device must have already left init for the previous ACI loop to have finished.
Signed-off-by: Trent Piepho xyzzy@speakeasy.org
diff -r ec96283a273f isa/ad1848/ad1848_lib.c --- a/isa/ad1848/ad1848_lib.c Mon Sep 17 19:20:48 2007 -0700 +++ b/isa/ad1848/ad1848_lib.c Mon Sep 17 19:22:36 2007 -0700 @@ -203,9 +203,8 @@ static void snd_ad1848_mce_up(struct snd
static void snd_ad1848_mce_down(struct snd_ad1848 *chip) {
- unsigned long flags;
- int timeout;
- unsigned long end_time;
unsigned long flags, timeout;
int regsel;
spin_lock_irqsave(&chip->reg_lock, flags); for (timeout = 5; timeout > 0; timeout--)
@@ -222,50 +221,34 @@ static void snd_ad1848_mce_down(struct s #endif
chip->mce_bit &= ~AD1848_MCE;
- timeout = inb(AD1848P(chip, REGSEL));
- outb(chip->mce_bit | (timeout & 0x1f), AD1848P(chip, REGSEL));
- if (timeout == 0x80)
- regsel = inb(AD1848P(chip, REGSEL));
- outb(chip->mce_bit | (regsel & 0x1f), AD1848P(chip, REGSEL));
- if (regsel == 0x80) snd_printk(KERN_WARNING "mce_down [0x%lx]: serious init problem - codec still busy\n", chip->port);
- if ((timeout & AD1848_MCE) == 0) {
if ((regsel & AD1848_MCE) == 0) { spin_unlock_irqrestore(&chip->reg_lock, flags); return; }
/*
* Wait for (possible -- during init auto-calibration may not be set)* calibration process to start. Needs upto 5 sample periods on AD1848* which at the slowest possible rate of 5.5125 kHz means 907 us.
* Wait for auto-calibration (AC) process to finish, i.e. ACI to go low.* It may take up to 5 sample periods (at most 907 us @ 5.5125 kHz) for* the process to _start_, so it is important to wait at least that long* before checking. Otherwise we might think AC has finished when it* has in fact not begun. It should take 128 (no AC) or 384 (AC) cycles* for ACI to drop. This gives a wait of at most 70 ms with a more* typical value of 3-9 ms.
- spin_unlock_irqrestore(&chip->reg_lock, flags);
- msleep(1);
- spin_lock_irqsave(&chip->reg_lock, flags);
- snd_printdd("(2) jiffies = %lu\n", jiffies);
- end_time = jiffies + msecs_to_jiffies(250);
- while (snd_ad1848_in(chip, AD1848_TEST_INIT) & AD1848_CALIB_IN_PROGRESS) {
- timeout = jiffies + msecs_to_jiffies(250);
- do { spin_unlock_irqrestore(&chip->reg_lock, flags);
if (time_after(jiffies, end_time)) {snd_printk(KERN_ERR "mce_down - auto calibration time out (2)\n");return;}- }
- snd_printdd("(3) jiffies = %lu\n", jiffies);
- end_time = jiffies + msecs_to_jiffies(100);
- while (inb(AD1848P(chip, REGSEL)) & AD1848_INIT) {
spin_unlock_irqrestore(&chip->reg_lock, flags);if (time_after(jiffies, end_time)) {snd_printk(KERN_ERR "mce_down - auto calibration time out (3)\n");return;}msleep(1);spin_lock_irqsave(&chip->reg_lock, flags);- }
- spin_unlock_irqrestore(&chip->reg_lock, flags);
regsel = snd_ad1848_in(chip, AD1848_TEST_INIT);- } while ((regsel & AD1848_CALIB_IN_PROGRESS) && time_before(jiffies, timeout));
Break this long line. You may calculate "regsel & AD1848_CALIB_IN_PROGRESS" inside the loop and use it in the condition outside the loop too.
Regards, Krzysztof