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[media] it913x: replace udelay polling with jiffies

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udelay based I/O polling loop is a bad idea, especially system
performance point of view. Kernel jiffies are preferred solution
for such situations. Use it instead.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
This commit is contained in:
Antti Palosaari 2014-08-31 00:29:33 -03:00 committed by Mauro Carvalho Chehab
parent 17027b9620
commit 5190ff3e3e
1 changed files with 20 additions and 9 deletions
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29
drivers/media/tuners/it913x.c
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@ -39,10 +39,11 @@ struct it913x_dev {
static int it913x_init(struct dvb_frontend *fe)
{
struct it913x_dev *dev = fe->tuner_priv;
int ret, i;
int ret;
unsigned int utmp;
u8 iqik_m_cal, nv_val, buf[2];
static const u8 nv[] = {48, 32, 24, 16, 12, 8, 6, 4, 2};
unsigned long timeout;
dev_dbg(&dev->client->dev, "role %u\n", dev->role);
@ -85,7 +86,9 @@ static int it913x_init(struct dvb_frontend *fe)
else
nv_val = 2;
for (i = 0; i < 50; i++) {
#define TIMEOUT 50
timeout = jiffies + msecs_to_jiffies(TIMEOUT);
while (!time_after(jiffies, timeout)) {
ret = regmap_bulk_read(dev->regmap, 0x80ed23, buf, 2);
if (ret)
goto err;
@ -93,30 +96,38 @@ static int it913x_init(struct dvb_frontend *fe)
utmp = (buf[1] << 8) | (buf[0] << 0);
if (utmp)
break;
udelay(2000);
}
dev_dbg(&dev->client->dev, "loop count %d, utmp %d\n", i, utmp);
dev_dbg(&dev->client->dev, "r_fbc_m_bdry took %u ms, val %u\n",
jiffies_to_msecs(jiffies) -
(jiffies_to_msecs(timeout) - TIMEOUT), utmp);
dev->fn_min = dev->xtal * utmp;
dev->fn_min /= (dev->fdiv * nv_val);
dev->fn_min *= 1000;
dev_dbg(&dev->client->dev, "fn_min %u\n", dev->fn_min);
/*
* Chip version BX never sets that flag so we just wait 50ms in that
* case. It is possible poll BX similarly than AX and then timeout in
* order to get 50ms delay, but that causes about 120 extra I2C
* messages. As for now, we just wait and reduce IO.
*/
if (dev->chip_ver == 1) {
for (i = 0; i < 50; i++) {
#define TIMEOUT 50
timeout = jiffies + msecs_to_jiffies(TIMEOUT);
while (!time_after(jiffies, timeout)) {
ret = regmap_read(dev->regmap, 0x80ec82, &utmp);
if (ret)
goto err;
if (utmp)
break;
udelay(2000);
}
dev_dbg(&dev->client->dev, "loop count %d\n", i);
dev_dbg(&dev->client->dev, "p_tsm_init_mode took %u ms, val %u\n",
jiffies_to_msecs(jiffies) -
(jiffies_to_msecs(timeout) - TIMEOUT), utmp);
} else {
msleep(50);
}