| Message ID | 20120629124719.2cf23f6b@endymion.delvare (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
This patch series should be applied after "i2c: Export an unlocked
flavor of i2c_transfer". It converts the drxk driver to use
request_firmware_nowait() and prevents I2C bus usage during firmware
load.
If firmware load doesn't happen and the device cannot be reset due
to that, -ENODEV will be returned to all dvb callbacks.
Mauro Carvalho Chehab (4):
[media] drxk: change it to use request_firmware_nowait()
[media] drxk: pass drxk priv struct instead of I2C adapter to i2c
calls
[media] drxk: Lock I2C bus during firmware load
[media] drxk: prevent doing something wrong when init is not ok
drivers/media/dvb/frontends/drxk_hard.c | 228 +++++++++++++++++++++++--------
drivers/media/dvb/frontends/drxk_hard.h | 16 ++-
2 files changed, 187 insertions(+), 57 deletions(-)
Hi Mauro! On Fri 29 June 2012 23:51:53 Mauro Carvalho Chehab wrote: > This patch series should be applied after "i2c: Export an unlocked > flavor of i2c_transfer". It converts the drxk driver to use > request_firmware_nowait() and prevents I2C bus usage during firmware > load. Can you take a look at media_build? After this change it fails to build drxk for kernels <= 3.4 (i.e., all kernels :-) ). Regards, Hans > > If firmware load doesn't happen and the device cannot be reset due > to that, -ENODEV will be returned to all dvb callbacks. > > Mauro Carvalho Chehab (4): > [media] drxk: change it to use request_firmware_nowait() > [media] drxk: pass drxk priv struct instead of I2C adapter to i2c > calls > [media] drxk: Lock I2C bus during firmware load > [media] drxk: prevent doing something wrong when init is not ok > > drivers/media/dvb/frontends/drxk_hard.c | 228 +++++++++++++++++++++++-------- > drivers/media/dvb/frontends/drxk_hard.h | 16 ++- > 2 files changed, 187 insertions(+), 57 deletions(-) > > -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- linux-3.5-rc4.orig/drivers/i2c/i2c-core.c 2012-06-05 16:22:59.000000000 +0200 +++ linux-3.5-rc4/drivers/i2c/i2c-core.c 2012-06-29 12:41:04.707793937 +0200 @@ -1312,6 +1312,37 @@ module_exit(i2c_exit); */ /** + * __i2c_transfer - unlocked flavor of i2c_transfer + * @adap: Handle to I2C bus + * @msgs: One or more messages to execute before STOP is issued to + * terminate the operation; each message begins with a START. + * @num: Number of messages to be executed. + * + * Returns negative errno, else the number of messages executed. + * + * Adapter lock must be held when calling this function. No debug logging + * takes place. adap->algo->master_xfer existence isn't checked. + */ +int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) +{ + unsigned long orig_jiffies; + int ret, try; + + /* Retry automatically on arbitration loss */ + orig_jiffies = jiffies; + for (ret = 0, try = 0; try <= adap->retries; try++) { + ret = adap->algo->master_xfer(adap, msgs, num); + if (ret != -EAGAIN) + break; + if (time_after(jiffies, orig_jiffies + adap->timeout)) + break; + } + + return ret; +} +EXPORT_SYMBOL(__i2c_transfer); + +/** * i2c_transfer - execute a single or combined I2C message * @adap: Handle to I2C bus * @msgs: One or more messages to execute before STOP is issued to @@ -1325,8 +1356,7 @@ module_exit(i2c_exit); */ int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) { - unsigned long orig_jiffies; - int ret, try; + int ret; /* REVISIT the fault reporting model here is weak: * @@ -1364,15 +1394,7 @@ int i2c_transfer(struct i2c_adapter *ada i2c_lock_adapter(adap); } - /* Retry automatically on arbitration loss */ - orig_jiffies = jiffies; - for (ret = 0, try = 0; try <= adap->retries; try++) { - ret = adap->algo->master_xfer(adap, msgs, num); - if (ret != -EAGAIN) - break; - if (time_after(jiffies, orig_jiffies + adap->timeout)) - break; - } + ret = __i2c_transfer(adap, msgs, num); i2c_unlock_adapter(adap); return ret; --- linux-3.5-rc4.orig/include/linux/i2c.h 2012-06-05 16:23:05.000000000 +0200 +++ linux-3.5-rc4/include/linux/i2c.h 2012-06-29 10:29:47.865621249 +0200 @@ -68,6 +68,9 @@ extern int i2c_master_recv(const struct */ extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num); +/* Unlocked flavor */ +extern int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, + int num); /* This is the very generalized SMBus access routine. You probably do not want to use this, though; one of the functions below may be much easier,
Some drivers (in particular for TV cards) need exclusive access to their I2C buses for specific operations. Export an unlocked flavor of i2c_transfer to give them full control. The unlocked flavor has the following limitations: * Obviously, caller must hold the i2c adapter lock. * No debug messages are logged. We don't want to log messages while holding a rt_mutex. * No check is done on the existence of adap->algo->master_xfer. It is thus the caller's responsibility to ensure that the function is OK to call. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Mauro Carvalho Chehab <mchehab@redhat.com> --- Mauro, would this be OK with you? drivers/i2c/i2c-core.c | 44 +++++++++++++++++++++++++++++++++----------- include/linux/i2c.h | 3 +++ 2 files changed, 36 insertions(+), 11 deletions(-)