Em Sun, 13 Aug 2017 19:47:37 +0100 Jemma Denson <jdenson@xxxxxxxxx> escreveu: > Hi Mauro, > > Just tried this on my card - unfortunately the patch as is doesn't work. > > On 13/08/17 13:10, Mauro Carvalho Chehab wrote: > > This Kaffeine's BZ: > > https://bugs.kde.org/show_bug.cgi?id=374693 > > > > affects SkyStar S2 PCI DVB-S/S2 rev 3.3 device. It could be due to > > a Kernel bug. > > > > While checking the Isil 6421, comparing with its manual, available at: > > > > http://www.intersil.com/content/dam/Intersil/documents/isl6/isl6421a.pdf > > > > It was noticed that, if the output load is highly capacitive, a different approach > > is recomended when energizing the LNBf. > > > > Also, it is possible to detect if a current overload is happening, by checking an > > special flag. > > > > Add support for it. > > > > Compile-tested only. > > > > Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx> > > --- > > drivers/media/dvb-frontends/isl6421.c | 72 +++++++++++++++++++++++++++++++++-- > > 1 file changed, 68 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/media/dvb-frontends/isl6421.c b/drivers/media/dvb-frontends/isl6421.c > > index 838b42771a05..47a7e559cef2 100644 > > --- a/drivers/media/dvb-frontends/isl6421.c > > +++ b/drivers/media/dvb-frontends/isl6421.c > > @@ -38,25 +38,43 @@ struct isl6421 { > > u8 override_and; > > struct i2c_adapter *i2c; > > u8 i2c_addr; > > + bool is_off; > > }; > > > > static int isl6421_set_voltage(struct dvb_frontend *fe, > > enum fe_sec_voltage voltage) > > { > > + int ret; > > + u8 buf; > > + bool is_off; > > struct isl6421 *isl6421 = (struct isl6421 *) fe->sec_priv; > > - struct i2c_msg msg = { .addr = isl6421->i2c_addr, .flags = 0, > > - .buf = &isl6421->config, > > - .len = sizeof(isl6421->config) }; > > + struct i2c_msg msg[2] = { > > + { > > + .addr = isl6421->i2c_addr, > > + .flags = 0, > > + .buf = &isl6421->config, > > + .len = 1, > > + }, { > > + .addr = isl6421->i2c_addr, > > + .flags = I2C_M_RD, > > + .buf = &buf, > > + .len = 1, > > + } > > + > > + }; > > > > isl6421->config &= ~(ISL6421_VSEL1 | ISL6421_EN1); > > > > switch(voltage) { > > case SEC_VOLTAGE_OFF: > > + is_off = true; > > break; > > case SEC_VOLTAGE_13: > > + is_off = false; > > isl6421->config |= ISL6421_EN1; > > break; > > case SEC_VOLTAGE_18: > > + is_off = false; > > isl6421->config |= (ISL6421_EN1 | ISL6421_VSEL1); > > break; > > default: > > @@ -66,7 +84,51 @@ static int isl6421_set_voltage(struct dvb_frontend *fe, > > isl6421->config |= isl6421->override_or; > > isl6421->config &= isl6421->override_and; > > > > - return (i2c_transfer(isl6421->i2c, &msg, 1) == 1) ? 0 : -EIO; > > + /* > > + * If LNBf were not powered on, disable dynamic current limit, as, > > + * according with datasheet, highly capacitive load on the output may > > + * cause a difficult start-up. > > + */ > > + if (isl6421->is_off && !is_off) > > + isl6421->config |= ISL6421_EN1; > > + > > + ret = i2c_transfer(isl6421->i2c, msg, 2); > > + if (ret < 0) > > + return ret; > > + if (ret != 1) > > + return -EIO; > > This needs to check ret != 2 > > > + > > + isl6421->is_off = is_off; > > + > > + /* On overflow, the device will try again after 900 ms (typically) */ > > + if (isl6421->is_off && (buf & ISL6421_OLF1)) > > + msleep(1000); > > + > > + if (isl6421->is_off && !is_off) { > > + isl6421->config &= ~ISL6421_EN1; > > + > > + ret = i2c_transfer(isl6421->i2c, msg, 2); > > + if (ret < 0) > > + return ret; > > + if (ret != 1) > > + return -EIO; > > + } > > Same again > > > + > > + /* Check if overload flag is active. If so, disable power */ > > + if (buf & ISL6421_OLF1) { > > + isl6421->config &= ~(ISL6421_VSEL1 | ISL6421_EN1); > > + ret = i2c_transfer(isl6421->i2c, msg, 1); > > + if (ret < 0) > > + return ret; > > + if (ret != 1) > > + return -EIO; > > + isl6421->is_off = true; > > + > > + dev_warn(&isl6421->i2c->dev, > > + "Overload current detected. disabling LNBf power\n"); > > + return -EINVAL; > > + } > > + return 0; > > } > > > > static int isl6421_enable_high_lnb_voltage(struct dvb_frontend *fe, long arg) > > @@ -148,6 +210,8 @@ struct dvb_frontend *isl6421_attach(struct dvb_frontend *fe, struct i2c_adapter > > return NULL; > > } > > > > + isl6421->is_off = true; > > + > > /* install release callback */ > > fe->ops.release_sec = isl6421_release; > > > > > Once I changed these it worked fine - I can still tune in with this > patch even switching from H to V. I've no idea if this fixes the bug > logged in kaffeine though as I haven't seen it. Hi Jemma, Thanks for testing! Just sent a v2 with the fixes you pointed. Please reply it with a tested-by. IMHO, detecting current overflow is a good improvement for the driver. I suspect that, in the case of Kaffeine's bug, the issue could also be due to a very long cabling. So, I'm preparing another patch that will let the user to optionally ask for a higher voltage (Isil 6421 allows selecting 14V/19V instead of the standard 13V/18V). Thanks, Mauro
