[PATCH 4/7] af9013 frontend tuner bus lock and gate changes v2

2011-11-12 Thread Malcolm Priestley
Changes from version 1
Remove the bus lock from read status. Causing a lagging
effect on some kernels  [2.6.38]

This does mean that noisy I2C traffic could be heard on
the first frontend when its tuner gate is open.

Signed-off-by: Malcolm Priestley tvbox...@gmail.com
---
 drivers/media/dvb/dvb-usb/af9015.c   |7 ++-
 drivers/media/dvb/frontends/af9013.c |9 -
 drivers/media/dvb/frontends/af9013.h |5 +++--
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/media/dvb/dvb-usb/af9015.c 
b/drivers/media/dvb/dvb-usb/af9015.c
index c9da2aa..9077ac4 100644
--- a/drivers/media/dvb/dvb-usb/af9015.c
+++ b/drivers/media/dvb/dvb-usb/af9015.c
@@ -46,6 +46,7 @@ module_param_named(no_pid, no_pid_filter, int, 0644);
 MODULE_PARM_DESC(no_pid, set default 0=on 1=off);
 
 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];
@@ -1147,7 +1148,7 @@ 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;
 }
@@ -1220,6 +1221,9 @@ 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:
@@ -1275,6 +1279,7 @@ 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..38a6ea2 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)
@@ -1446,7 +1452,7 @@ 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 +1465,7 @@ 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




--
To unsubscribe from this list: send the line unsubscribe linux-media in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html


Re: [PATCH 4/7] af9013 frontend tuner bus lock and gate changes v2

2011-11-12 Thread Antti Palosaari

On 11/12/2011 05:55 PM, Malcolm Priestley wrote:

Changes from version 1
Remove the bus lock from read status. Causing a lagging
effect on some kernels  [2.6.38]

This does mean that noisy I2C traffic could be heard on
the first frontend when its tuner gate is open.


I think you want add locking for tuner set. But this seems to be now 
removing it.


* tuner gate is not normally open, it is only open very small period 
when tuner is programmed, init or sleep.

* I think gate is not reason for I2C errors seen in log

Finally I think, you want lock tuner set. Than is easiest to do locking 
whole .set_frontend(). I haven't tested it, but testing it have been on 
my TODO some time.


Antti


--
http://palosaari.fi/
--
To unsubscribe from this list: send the line unsubscribe linux-media in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html