diff options
author | Antti Palosaari <crope@iki.fi> | 2014-08-31 00:29:33 -0300 |
---|---|---|
committer | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2014-09-21 18:29:34 -0300 |
commit | 5190ff3e3e6ec55ecda805e68c4746aec8c1203c (patch) | |
tree | e834617831227e28aa356e757b4b68ddce44b88c /drivers/media | |
parent | 17027b9620e6a2ea1d7f3cd0761803c44c65e2ed (diff) | |
download | op-kernel-dev-5190ff3e3e6ec55ecda805e68c4746aec8c1203c.zip op-kernel-dev-5190ff3e3e6ec55ecda805e68c4746aec8c1203c.tar.gz |
[media] it913x: replace udelay polling with jiffies
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>
Diffstat (limited to 'drivers/media')
-rw-r--r-- | drivers/media/tuners/it913x.c | 29 |
1 files changed, 20 insertions, 9 deletions
diff --git a/drivers/media/tuners/it913x.c b/drivers/media/tuners/it913x.c index 098e9d5..a076c87 100644 --- a/drivers/media/tuners/it913x.c +++ b/drivers/media/tuners/it913x.c @@ -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); } |