Frontend bus lock for af9015 devices.
Last week, I aqcuired a dual KWorld PlusTV Dual DVB-T Stick (DVB-T 399U).
The lock is intended for dual frontends that share the same tuner I2C address
to stop either frontend sending data while any gate is open. The patch
should have no effect on single devices or multiple single devices, well
not on the ones I have!
It also delays read_status call backs being sent while either gate is open, a
mostly like cause of corruption.
The lock also covers the attachment process of the tuner in case there is any
race condition, although unlikely.
Points about troubles with Myth TV;
Streaming corruptions are more likely to appear from the I2C noise generated
from setting either frontend. Afatech love their bits as bytes:-)
Latest version of Myth TV appears to have a bug where you can't select the second
frontend independently and when it does it tunes to the same frequency as
the first frontend!
Signed-off-by: Malcolm Priestley <tvboxspy@xxxxxxxxx>
---
drivers/media/dvb/dvb-usb/af9015.c | 7 ++++++-
drivers/media/dvb/frontends/af9013.c | 13 ++++++++++++-
drivers/media/dvb/frontends/af9013.h | 5 +++--
3 files changed, 21 insertions(+), 4 deletions(-)
diff --git a/drivers/media/dvb/dvb-usb/af9015.c b/drivers/media/dvb/dvb-usb/af9015.c
index c6c275b..0089858 100644
--- a/drivers/media/dvb/dvb-usb/af9015.c
+++ b/drivers/media/dvb/dvb-usb/af9015.c
@@ -43,6 +43,7 @@ MODULE_PARM_DESC(remote, "select remote");
DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);
static DEFINE_MUTEX(af9015_usb_mutex);
+static DEFINE_MUTEX(af9015_fe_mutex);
static struct af9015_config af9015_config;
static struct dvb_usb_device_properties af9015_properties[3];
@@ -1114,7 +1115,7 @@ static int af9015_af9013_frontend_attach(struct dvb_usb_adapter *adap)
/* attach demodulator */
adap->fe_adap[0].fe = dvb_attach(af9013_attach, &af9015_af9013_config[adap->id],
- &adap->dev->i2c_adap);
+ &adap->dev->i2c_adap, &af9015_fe_mutex);
return adap->fe_adap[0].fe == NULL ? -ENODEV : 0;
}
@@ -1187,6 +1188,9 @@ static int af9015_tuner_attach(struct dvb_usb_adapter *adap)
int ret;
deb_info("%s:\n", __func__);
+ if (mutex_lock_interruptible(&af9015_fe_mutex) < 0)
+ return -EAGAIN;
+
switch (af9015_af9013_config[adap->id].tuner) {
case AF9013_TUNER_MT2060:
case AF9013_TUNER_MT2060_2:
@@ -1242,6 +1246,7 @@ static int af9015_tuner_attach(struct dvb_usb_adapter *adap)
err("Unknown tuner id:%d",
af9015_af9013_config[adap->id].tuner);
}
+ mutex_unlock(&af9015_fe_mutex);
return ret;
}
diff --git a/drivers/media/dvb/frontends/af9013.c b/drivers/media/dvb/frontends/af9013.c
index 345311c..b220a87 100644
--- a/drivers/media/dvb/frontends/af9013.c
+++ b/drivers/media/dvb/frontends/af9013.c
@@ -50,6 +50,7 @@ struct af9013_state {
u16 snr;
u32 frequency;
unsigned long next_statistics_check;
+ struct mutex *fe_mutex;
};
static u8 regmask[8] = { 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff };
@@ -630,9 +631,14 @@ static int af9013_set_frontend(struct dvb_frontend *fe,
state->frequency = params->frequency;
/* program tuner */
+ if (mutex_lock_interruptible(state->fe_mutex) < 0)
+ return -EAGAIN;
+
if (fe->ops.tuner_ops.set_params)
fe->ops.tuner_ops.set_params(fe, params);
+ mutex_unlock(state->fe_mutex);
+
/* program CFOE coefficients */
ret = af9013_set_coeff(state, params->u.ofdm.bandwidth);
if (ret)
@@ -1038,6 +1044,9 @@ static int af9013_read_status(struct dvb_frontend *fe, fe_status_t *status)
u8 tmp;
*status = 0;
+ if (mutex_lock_interruptible(state->fe_mutex) < 0)
+ return -EAGAIN;
+
/* MPEG2 lock */
ret = af9013_read_reg_bits(state, 0xd507, 6, 1, &tmp);
if (ret)
@@ -1086,6 +1095,7 @@ static int af9013_read_status(struct dvb_frontend *fe, fe_status_t *status)
ret = af9013_update_statistics(fe);
error:
+ mutex_unlock(state->fe_mutex);
return ret;
}
@@ -1446,7 +1456,7 @@ static void af9013_release(struct dvb_frontend *fe)
static struct dvb_frontend_ops af9013_ops;
struct dvb_frontend *af9013_attach(const struct af9013_config *config,
- struct i2c_adapter *i2c)
+ struct i2c_adapter *i2c, struct mutex *fe_mutex)
{
int ret;
struct af9013_state *state = NULL;
@@ -1459,6 +1469,7 @@ struct dvb_frontend *af9013_attach(const struct af9013_config *config,
/* setup the state */
state->i2c = i2c;
+ state->fe_mutex = fe_mutex;
memcpy(&state->config, config, sizeof(struct af9013_config));
/* download firmware */
diff --git a/drivers/media/dvb/frontends/af9013.h b/drivers/media/dvb/frontends/af9013.h
index e53d873..95c966a 100644
--- a/drivers/media/dvb/frontends/af9013.h
+++ b/drivers/media/dvb/frontends/af9013.h
@@ -96,10 +96,11 @@ struct af9013_config {
#if defined(CONFIG_DVB_AF9013) || \
(defined(CONFIG_DVB_AF9013_MODULE) && defined(MODULE))
extern struct dvb_frontend *af9013_attach(const struct af9013_config *config,
- struct i2c_adapter *i2c);
+ struct i2c_adapter *i2c, struct mutex *fe_mutex);
#else
static inline struct dvb_frontend *af9013_attach(
-const struct af9013_config *config, struct i2c_adapter *i2c)
+ const struct af9013_config *config, struct i2c_adapter *i2,
+ struct mutex *fe_mutex)
{
printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__);
return NULL;
--
1.7.5.4
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