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path: root/drivers/media/dvb/pt1/va1j5jf8007s.c
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Diffstat (limited to 'drivers/media/dvb/pt1/va1j5jf8007s.c')
-rw-r--r--drivers/media/dvb/pt1/va1j5jf8007s.c57
1 files changed, 56 insertions, 1 deletions
diff --git a/drivers/media/dvb/pt1/va1j5jf8007s.c b/drivers/media/dvb/pt1/va1j5jf8007s.c
index 2db940f..fc65949 100644
--- a/drivers/media/dvb/pt1/va1j5jf8007s.c
+++ b/drivers/media/dvb/pt1/va1j5jf8007s.c
@@ -48,6 +48,60 @@ struct va1j5jf8007s_state {
enum va1j5jf8007s_tune_state tune_state;
};
+static int va1j5jf8007s_read_snr(struct dvb_frontend *fe, u16 *snr)
+{
+ struct va1j5jf8007s_state *state;
+ u8 addr;
+ int i;
+ u8 write_buf[1], read_buf[1];
+ struct i2c_msg msgs[2];
+ s32 word, x1, x2, x3, x4, x5, y;
+
+ state = fe->demodulator_priv;
+ addr = state->config->demod_address;
+
+ word = 0;
+ for (i = 0; i < 2; i++) {
+ write_buf[0] = 0xbc + i;
+
+ msgs[0].addr = addr;
+ msgs[0].flags = 0;
+ msgs[0].len = sizeof(write_buf);
+ msgs[0].buf = write_buf;
+
+ msgs[1].addr = addr;
+ msgs[1].flags = I2C_M_RD;
+ msgs[1].len = sizeof(read_buf);
+ msgs[1].buf = read_buf;
+
+ if (i2c_transfer(state->adap, msgs, 2) != 2)
+ return -EREMOTEIO;
+
+ word <<= 8;
+ word |= read_buf[0];
+ }
+
+ word -= 3000;
+ if (word < 0)
+ word = 0;
+
+ x1 = int_sqrt(word << 16) * ((15625ll << 21) / 1000000);
+ x2 = (s64)x1 * x1 >> 31;
+ x3 = (s64)x2 * x1 >> 31;
+ x4 = (s64)x2 * x2 >> 31;
+ x5 = (s64)x4 * x1 >> 31;
+
+ y = (58857ll << 23) / 1000;
+ y -= (s64)x1 * ((89565ll << 24) / 1000) >> 30;
+ y += (s64)x2 * ((88977ll << 24) / 1000) >> 28;
+ y -= (s64)x3 * ((50259ll << 25) / 1000) >> 27;
+ y += (s64)x4 * ((14341ll << 27) / 1000) >> 27;
+ y -= (s64)x5 * ((16346ll << 30) / 10000) >> 28;
+
+ *snr = y < 0 ? 0 : y >> 15;
+ return 0;
+}
+
static int va1j5jf8007s_get_frontend_algo(struct dvb_frontend *fe)
{
return DVBFE_ALGO_HW;
@@ -337,7 +391,7 @@ va1j5jf8007s_tune(struct dvb_frontend *fe,
{
struct va1j5jf8007s_state *state;
int ret;
- int lock;
+ int lock = 0;
state = fe->demodulator_priv;
@@ -536,6 +590,7 @@ static struct dvb_frontend_ops va1j5jf8007s_ops = {
FE_CAN_GUARD_INTERVAL_AUTO | FE_CAN_HIERARCHY_AUTO,
},
+ .read_snr = va1j5jf8007s_read_snr,
.get_frontend_algo = va1j5jf8007s_get_frontend_algo,
.read_status = va1j5jf8007s_read_status,
.tune = va1j5jf8007s_tune,