[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>

1 files changed, 20 insertions, 9 deletions

diff --git a/drivers/media/tuners/it913x.c b/drivers/media/tuners/it913x.c
index 098e9d542708..a076c87eda7a 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);
         }