V4L/DVB (13394): pt1: Support FE_READ_SNR

Signed-off-by: HIRANO Takahito <hiranotaka@zng.info>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
hiranotaka@zng.jp 2009-11-08 05:42:28 -03:00 committed by Mauro Carvalho Chehab
parent 012880be6e
commit c4c1e295d2
2 changed files with 102 additions and 0 deletions

View File

@ -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;
@ -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,

View File

@ -46,6 +46,52 @@ struct va1j5jf8007t_state {
enum va1j5jf8007t_tune_state tune_state;
};
static int va1j5jf8007t_read_snr(struct dvb_frontend *fe, u16 *snr)
{
struct va1j5jf8007t_state *state;
u8 addr;
int i;
u8 write_buf[1], read_buf[1];
struct i2c_msg msgs[2];
s32 word, x, y;
state = fe->demodulator_priv;
addr = state->config->demod_address;
word = 0;
for (i = 0; i < 3; i++) {
write_buf[0] = 0x8b + 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];
}
if (!word)
return -EIO;
x = 10 * (intlog10(0x540000 * 100 / word) - (2 << 24));
y = (24ll << 46) / 1000000;
y = ((s64)y * x >> 30) - (16ll << 40) / 10000;
y = ((s64)y * x >> 29) + (398ll << 35) / 10000;
y = ((s64)y * x >> 30) + (5491ll << 29) / 10000;
y = ((s64)y * x >> 30) + (30965ll << 23) / 10000;
*snr = y >> 15;
return 0;
}
static int va1j5jf8007t_get_frontend_algo(struct dvb_frontend *fe)
{
return DVBFE_ALGO_HW;
@ -393,6 +439,7 @@ static struct dvb_frontend_ops va1j5jf8007t_ops = {
FE_CAN_GUARD_INTERVAL_AUTO | FE_CAN_HIERARCHY_AUTO,
},
.read_snr = va1j5jf8007t_read_snr,
.get_frontend_algo = va1j5jf8007t_get_frontend_algo,
.read_status = va1j5jf8007t_read_status,
.tune = va1j5jf8007t_tune,