linux/drivers/media/dvb-frontends/ts2020.h

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/*
Montage Technology TS2020 - Silicon Tuner driver
Copyright (C) 2009-2012 Konstantin Dimitrov <kosio.dimitrov@gmail.com>
Copyright (C) 2009-2012 TurboSight.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef TS2020_H
#define TS2020_H
#include <linux/dvb/frontend.h>
struct ts2020_config {
u8 tuner_address;
u32 frequency_div;
/*
* RF loop-through
*/
bool loop_through:1;
/*
* clock output
*/
#define TS2020_CLK_OUT_DISABLED 0
#define TS2020_CLK_OUT_ENABLED 1
#define TS2020_CLK_OUT_ENABLED_XTALOUT 2
u8 clk_out:2;
/*
* clock output divider
* 1 - 31
*/
u8 clk_out_div:5;
/* Set to true to suppress stat polling */
bool dont_poll:1;
/*
* pointer to DVB frontend
*/
struct dvb_frontend *fe;
/*
* driver private, do not set value
*/
u8 attach_in_use:1;
[media] TS2020: Calculate tuner gain correctly The TS2020 and TS2022 tuners take an input from the demodulator indicating the AGC setting on that component that is then used to influence the tuner's own gain. This should be taken into account when calculating the gain and signal strength. Further, the existing TS2020 driver miscalculates the signal strength as the result of its calculations can exceed the storage capacity of the 16-bit word used to return it to userspace. To this end: (1) Add a callback function (->get_agc_pwm()) in the ts2020_config struct that the tuner can call to get the AGC PWM value from the demodulator. (2) Modify the TS2020 driver to calculate the gain according to Montage's specification with the adjustment that we produce a negative value and scale it to 0.001dB units (which is what the DVBv5 API will require): (a) Callback to the demodulator to retrieve the AGC PWM value and then turn that into Vagc for incorporation in the calculations. If the callback is unset, assume a Vagc of 0. (b) Calculate the tuner gain from a combination of Vagc and the tuner's RF gain and baseband gain settings. (3) Turn this into a percentage signal strength as per Montage's specification for return to userspace with the DVBv3 API. (4) Provide a function in the M88DS3103 demodulator driver that can be used to get the AGC PWM value on behalf of the tuner. (5) The ts2020_config.get_agc_pwm function should be set by the code that stitches together the drivers for each card. For the DVBSky cards that use the M88DS3103 with the TS2020 or the TS2022, set the get_agc_pwm function to point to m88ds3103_get_agc_pwm. I have tested this with a DVBSky S952 card which has an M88DS3103 and a TS2022. Thanks to Montage for providing access to information about the workings of these parts. Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Antti Palosaari <crope@iki.fi> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-05-26 23:04:00 +08:00
/* Operation to be called by the ts2020 driver to get the value of the
* AGC PWM tuner input as theoretically output by the demodulator.
*/
int (*get_agc_pwm)(struct dvb_frontend *fe, u8 *_agc_pwm);
};
/* Do not add new ts2020_attach() users! Use I2C bindings instead. */
[media] Add and use IS_REACHABLE macro In the media drivers, the v4l2 core knows about all submodules and calls into them from a common function. However this cannot work if the modules that get called are loadable and the core is built-in. In that case we get drivers/built-in.o: In function `set_type': drivers/media/v4l2-core/tuner-core.c:301: undefined reference to `tea5767_attach' drivers/media/v4l2-core/tuner-core.c:307: undefined reference to `tea5761_attach' drivers/media/v4l2-core/tuner-core.c:349: undefined reference to `tda9887_attach' drivers/media/v4l2-core/tuner-core.c:405: undefined reference to `xc4000_attach' This was working previously, until the IS_ENABLED() macro was used to replace the construct like #if defined(CONFIG_DVB_CX24110) || (defined(CONFIG_DVB_CX24110_MODULE) && defined(MODULE)) with the difference that the new code no longer checks whether it is being built as a loadable module itself. To fix this, this new patch adds an 'IS_REACHABLE' macro, which evaluates true in exactly the condition that was used previously. The downside of this is that this trades an obvious link error for a more subtle runtime failure, but it is clear that the change that introduced the link error was unintentional and it seems better to revert it for now. Also, a similar change was originally created by Trent Piepho and then reverted by teh change to the IS_ENABLED macro. Ideally Kconfig would be used to avoid the case of a broken dependency, or the code restructured in a way to turn around the dependency, but either way would require much larger changes here. Fixes: 7b34be71db53 ("[media] use IS_ENABLED() macro") See-also: c5dec9fb248e ("V4L/DVB (4751): Fix DBV_FE_CUSTOMISE for card drivers compiled into kernel") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
2015-02-19 01:12:42 +08:00
#if IS_REACHABLE(CONFIG_DVB_TS2020)
extern struct dvb_frontend *ts2020_attach(
struct dvb_frontend *fe,
const struct ts2020_config *config,
struct i2c_adapter *i2c);
#else
static inline struct dvb_frontend *ts2020_attach(
struct dvb_frontend *fe,
const struct ts2020_config *config,
struct i2c_adapter *i2c)
{
printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__);
return NULL;
}
#endif
#endif /* TS2020_H */