[ALSA] maestro3.c: fix BUG, optimization
- fix brown-paper-bag locking bug (lock() / return / unlock())
- improve central function snd_m3_update_ptr()
(avoid expensive integer divisions)
- add cpu_relax() to busy-wait I/O loop as recommended
(does this require special macro support in ALSA for older kernels??)
- constify several structs
- spelling updates
Signed-off-by: Andreas Mohr <andi@lisas.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/pci/maestro3.c b/sound/pci/maestro3.c
index 44393e1..9c90d90 100644
--- a/sound/pci/maestro3.c
+++ b/sound/pci/maestro3.c
@@ -831,8 +831,8 @@
struct snd_pcm *pcm;
struct pci_dev *pci;
- struct m3_quirk *quirk;
- struct m3_hv_quirk *hv_quirk;
+ const struct m3_quirk *quirk;
+ const struct m3_hv_quirk *hv_quirk;
int dacs_active;
int timer_users;
@@ -892,7 +892,7 @@
MODULE_DEVICE_TABLE(pci, snd_m3_ids);
-static struct m3_quirk m3_quirk_list[] = {
+static const struct m3_quirk m3_quirk_list[] = {
/* panasonic CF-28 "toughbook" */
{
.name = "Panasonic CF-28",
@@ -950,7 +950,7 @@
};
/* These values came from the Windows driver. */
-static struct m3_hv_quirk m3_hv_quirk_list[] = {
+static const struct m3_hv_quirk m3_hv_quirk_list[] = {
/* Allegro chips */
{ 0x125D, 0x1988, 0x0E11, 0x002E, HV_CTRL_ENABLE | HV_BUTTON_FROM_GD, 0 },
{ 0x125D, 0x1988, 0x0E11, 0x0094, HV_CTRL_ENABLE | HV_BUTTON_FROM_GD, 0 },
@@ -1361,7 +1361,7 @@
}
-static struct play_vals {
+static const struct play_vals {
u16 addr, val;
} pv[] = {
{CDATA_LEFT_VOLUME, ARB_VOLUME},
@@ -1428,7 +1428,7 @@
/*
* Native record driver
*/
-static struct rec_vals {
+static const struct rec_vals {
u16 addr, val;
} rv[] = {
{CDATA_LEFT_VOLUME, ARB_VOLUME},
@@ -1598,12 +1598,26 @@
if (! s->running)
return;
- hwptr = snd_m3_get_pointer(chip, s, subs) % s->dma_size;
- diff = (s->dma_size + hwptr - s->hwptr) % s->dma_size;
+ hwptr = snd_m3_get_pointer(chip, s, subs);
+
+ /* try to avoid expensive modulo divisions */
+ if (hwptr >= s->dma_size)
+ hwptr %= s->dma_size;
+
+ diff = s->dma_size + hwptr - s->hwptr;
+ if (diff >= s->dma_size)
+ diff %= s->dma_size;
+
s->hwptr = hwptr;
s->count += diff;
+
if (s->count >= (signed)s->period_size) {
- s->count %= s->period_size;
+
+ if (s->count < 2 * (signed)s->period_size)
+ s->count -= (signed)s->period_size;
+ else
+ s->count %= s->period_size;
+
spin_unlock(&chip->reg_lock);
snd_pcm_period_elapsed(subs);
spin_lock(&chip->reg_lock);
@@ -1942,6 +1956,7 @@
do {
if (! (snd_m3_inb(chip, 0x30) & 1))
return 0;
+ cpu_relax();
} while (i-- > 0);
snd_printk(KERN_ERR "ac97 serial bus busy\n");
@@ -1953,16 +1968,18 @@
{
struct snd_m3 *chip = ac97->private_data;
unsigned long flags;
- unsigned short data;
+ unsigned short data = 0xffff;
if (snd_m3_ac97_wait(chip))
- return 0xffff;
+ goto fail;
spin_lock_irqsave(&chip->ac97_lock, flags);
snd_m3_outb(chip, 0x80 | (reg & 0x7f), CODEC_COMMAND);
if (snd_m3_ac97_wait(chip))
- return 0xffff;
+ goto fail_unlock;
data = snd_m3_inw(chip, CODEC_DATA);
+fail_unlock:
spin_unlock_irqrestore(&chip->ac97_lock, flags);
+fail:
return data;
}
@@ -2121,7 +2138,7 @@
* DSP Code images
*/
-static u16 assp_kernel_image[] __devinitdata = {
+static const u16 assp_kernel_image[] __devinitdata = {
0x7980, 0x0030, 0x7980, 0x03B4, 0x7980, 0x03B4, 0x7980, 0x00FB, 0x7980, 0x00DD, 0x7980, 0x03B4,
0x7980, 0x0332, 0x7980, 0x0287, 0x7980, 0x03B4, 0x7980, 0x03B4, 0x7980, 0x03B4, 0x7980, 0x03B4,
0x7980, 0x031A, 0x7980, 0x03B4, 0x7980, 0x022F, 0x7980, 0x03B4, 0x7980, 0x03B4, 0x7980, 0x03B4,
@@ -2208,7 +2225,7 @@
* Mini sample rate converter code image
* that is to be loaded at 0x400 on the DSP.
*/
-static u16 assp_minisrc_image[] __devinitdata = {
+static const u16 assp_minisrc_image[] __devinitdata = {
0xBF80, 0x101E, 0x906E, 0x006E, 0x8B88, 0x6980, 0xEF88, 0x906F, 0x0D6F, 0x6900, 0xEB08, 0x0412,
0xBC20, 0x696E, 0xB801, 0x906E, 0x7980, 0x0403, 0xB90E, 0x8807, 0xBE43, 0xBF01, 0xBE47, 0xBE41,
@@ -2251,7 +2268,7 @@
*/
#define MINISRC_LPF_LEN 10
-static u16 minisrc_lpf[MINISRC_LPF_LEN] __devinitdata = {
+static const u16 minisrc_lpf[MINISRC_LPF_LEN] __devinitdata = {
0X0743, 0X1104, 0X0A4C, 0XF88D, 0X242C,
0X1023, 0X1AA9, 0X0B60, 0XEFDD, 0X186F
};
@@ -2358,7 +2375,7 @@
*/
/*
- * align instance address to 256 bytes so that it's
+ * align instance address to 256 bytes so that its
* shifted list address is aligned.
* list address = (mem address >> 1) >> 7;
*/
@@ -2647,8 +2664,8 @@
{
struct snd_m3 *chip;
int i, err;
- struct m3_quirk *quirk;
- struct m3_hv_quirk *hv_quirk;
+ const struct m3_quirk *quirk;
+ const struct m3_hv_quirk *hv_quirk;
static struct snd_device_ops ops = {
.dev_free = snd_m3_dev_free,
};
@@ -2843,12 +2860,12 @@
}
#if 0 /* TODO: not supported yet */
- /* TODO enable midi irq and i/o */
+ /* TODO enable MIDI IRQ and I/O */
err = snd_mpu401_uart_new(chip->card, 0, MPU401_HW_MPU401,
chip->iobase + MPU401_DATA_PORT, 1,
chip->irq, 0, &chip->rmidi);
if (err < 0)
- printk(KERN_WARNING "maestro3: no midi support.\n");
+ printk(KERN_WARNING "maestro3: no MIDI support.\n");
#endif
pci_set_drvdata(pci, card);