[media] tda18218: re-implement tda18218_wr_regs()

Old i2c message length splitting logic was faulty. Make it better.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/tuners/tda18218.c b/drivers/media/tuners/tda18218.c
index 8a6f9ca..c400440 100644 (file)
--- a/drivers/media/tuners/tda18218.c
+++ b/drivers/media/tuners/tda18218.c
@@ -28,8 +28,8 @@ MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
 /* write multiple registers */
 static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
 {
-       int ret = 0;
-       u8 buf[1+len], quotient, remainder, i, msg_len, msg_len_max;
+       int ret = 0, len2, remaining;
+       u8 buf[1 + len];
        struct i2c_msg msg[1] = {
                {
                        .addr = priv->cfg->i2c_address,
@@ -38,17 +38,15 @@ static int tda18218_wr_regs(struct tda18218_priv *priv, u8 reg, u8 *val, u8 len)
                }
        };
 
-       msg_len_max = priv->cfg->i2c_wr_max - 1;
-       quotient = len / msg_len_max;
-       remainder = len % msg_len_max;
-       msg_len = msg_len_max;
-       for (i = 0; (i <= quotient && remainder); i++) {
-               if (i == quotient)  /* set len of the last msg */
-                       msg_len = remainder;
-
-               msg[0].len = msg_len + 1;
-               buf[0] = reg + i * msg_len_max;
-               memcpy(&buf[1], &val[i * msg_len_max], msg_len);
+       for (remaining = len; remaining > 0;
+                       remaining -= (priv->cfg->i2c_wr_max - 1)) {
+               len2 = remaining;
+               if (len2 > (priv->cfg->i2c_wr_max - 1))
+                       len2 = (priv->cfg->i2c_wr_max - 1);
+
+               msg[0].len = 1 + len2;
+               buf[0] = reg + len - remaining;
+               memcpy(&buf[1], &val[len - remaining], len2);
 
                ret = i2c_transfer(priv->i2c, msg, 1);
                if (ret != 1)