linux/drivers/media/dvb-frontends/s5h1432.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

92 lines
2.7 KiB
C

/*
* Samsung s5h1432 VSB/QAM demodulator driver
*
* Copyright (C) 2009 Bill Liu <Bill.Liu@Conexant.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 __S5H1432_H__
#define __S5H1432_H__
#include <linux/kconfig.h>
#include <linux/dvb/frontend.h>
#define S5H1432_I2C_TOP_ADDR (0x02 >> 1)
#define TAIWAN_HI_IF_FREQ_44_MHZ 44000000
#define EUROPE_HI_IF_FREQ_36_MHZ 36000000
#define IF_FREQ_6_MHZ 6000000
#define IF_FREQ_3point3_MHZ 3300000
#define IF_FREQ_3point5_MHZ 3500000
#define IF_FREQ_4_MHZ 4000000
struct s5h1432_config {
/* serial/parallel output */
#define S5H1432_PARALLEL_OUTPUT 0
#define S5H1432_SERIAL_OUTPUT 1
u8 output_mode;
/* GPIO Setting */
#define S5H1432_GPIO_OFF 0
#define S5H1432_GPIO_ON 1
u8 gpio;
/* MPEG signal timing */
#define S5H1432_MPEGTIMING_CONTINOUS_INVERTING_CLOCK 0
#define S5H1432_MPEGTIMING_CONTINOUS_NONINVERTING_CLOCK 1
#define S5H1432_MPEGTIMING_NONCONTINOUS_INVERTING_CLOCK 2
#define S5H1432_MPEGTIMING_NONCONTINOUS_NONINVERTING_CLOCK 3
u16 mpeg_timing;
/* IF Freq for QAM and VSB in KHz */
#define S5H1432_IF_3250 3250
#define S5H1432_IF_3500 3500
#define S5H1432_IF_4000 4000
#define S5H1432_IF_5380 5380
#define S5H1432_IF_44000 44000
#define S5H1432_VSB_IF_DEFAULT s5h1432_IF_44000
#define S5H1432_QAM_IF_DEFAULT s5h1432_IF_44000
u16 qam_if;
u16 vsb_if;
/* Spectral Inversion */
#define S5H1432_INVERSION_OFF 0
#define S5H1432_INVERSION_ON 1
u8 inversion;
/* Return lock status based on tuner lock, or demod lock */
#define S5H1432_TUNERLOCKING 0
#define S5H1432_DEMODLOCKING 1
u8 status_mode;
};
#if IS_REACHABLE(CONFIG_DVB_S5H1432)
extern struct dvb_frontend *s5h1432_attach(const struct s5h1432_config *config,
struct i2c_adapter *i2c);
#else
static inline struct dvb_frontend *s5h1432_attach(const struct s5h1432_config
*config,
struct i2c_adapter *i2c)
{
printk(KERN_WARNING "%s: driver disabled by Kconfig\n", __func__);
return NULL;
}
#endif /* CONFIG_DVB_s5h1432 */
#endif /* __s5h1432_H__ */