linux/drivers/media/tuners/mxl5007t.h
Arnd Bergmann 9b174527e7 [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: 7b34be71db ("[media] use IS_ENABLED() macro")
See-also: c5dec9fb24 ("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>
2015-04-08 15:02:07 -03:00

96 lines
2.9 KiB
C

/*
* mxl5007t.h - driver for the MaxLinear MxL5007T silicon tuner
*
* Copyright (C) 2008 Michael Krufky <mkrufky@linuxtv.org>
*
* 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 __MXL5007T_H__
#define __MXL5007T_H__
#include "dvb_frontend.h"
/* ------------------------------------------------------------------------- */
enum mxl5007t_if_freq {
MxL_IF_4_MHZ, /* 4000000 */
MxL_IF_4_5_MHZ, /* 4500000 */
MxL_IF_4_57_MHZ, /* 4570000 */
MxL_IF_5_MHZ, /* 5000000 */
MxL_IF_5_38_MHZ, /* 5380000 */
MxL_IF_6_MHZ, /* 6000000 */
MxL_IF_6_28_MHZ, /* 6280000 */
MxL_IF_9_1915_MHZ, /* 9191500 */
MxL_IF_35_25_MHZ, /* 35250000 */
MxL_IF_36_15_MHZ, /* 36150000 */
MxL_IF_44_MHZ, /* 44000000 */
};
enum mxl5007t_xtal_freq {
MxL_XTAL_16_MHZ, /* 16000000 */
MxL_XTAL_20_MHZ, /* 20000000 */
MxL_XTAL_20_25_MHZ, /* 20250000 */
MxL_XTAL_20_48_MHZ, /* 20480000 */
MxL_XTAL_24_MHZ, /* 24000000 */
MxL_XTAL_25_MHZ, /* 25000000 */
MxL_XTAL_25_14_MHZ, /* 25140000 */
MxL_XTAL_27_MHZ, /* 27000000 */
MxL_XTAL_28_8_MHZ, /* 28800000 */
MxL_XTAL_32_MHZ, /* 32000000 */
MxL_XTAL_40_MHZ, /* 40000000 */
MxL_XTAL_44_MHZ, /* 44000000 */
MxL_XTAL_48_MHZ, /* 48000000 */
MxL_XTAL_49_3811_MHZ, /* 49381100 */
};
enum mxl5007t_clkout_amp {
MxL_CLKOUT_AMP_0_94V = 0,
MxL_CLKOUT_AMP_0_53V = 1,
MxL_CLKOUT_AMP_0_37V = 2,
MxL_CLKOUT_AMP_0_28V = 3,
MxL_CLKOUT_AMP_0_23V = 4,
MxL_CLKOUT_AMP_0_20V = 5,
MxL_CLKOUT_AMP_0_17V = 6,
MxL_CLKOUT_AMP_0_15V = 7,
};
struct mxl5007t_config {
s32 if_diff_out_level;
enum mxl5007t_clkout_amp clk_out_amp;
enum mxl5007t_xtal_freq xtal_freq_hz;
enum mxl5007t_if_freq if_freq_hz;
unsigned int invert_if:1;
unsigned int loop_thru_enable:1;
unsigned int clk_out_enable:1;
};
#if IS_REACHABLE(CONFIG_MEDIA_TUNER_MXL5007T)
extern struct dvb_frontend *mxl5007t_attach(struct dvb_frontend *fe,
struct i2c_adapter *i2c, u8 addr,
struct mxl5007t_config *cfg);
#else
static inline struct dvb_frontend *mxl5007t_attach(struct dvb_frontend *fe,
struct i2c_adapter *i2c,
u8 addr,
struct mxl5007t_config *cfg)
{
printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__);
return NULL;
}
#endif
#endif /* __MXL5007T_H__ */