linux/drivers/media/rc/rc-core-priv.h
James Hogan df1caa587a [media] rc/ir-raw: use kfifo_rec_ptr_1 instead of kfifo
Raw IR events are passed to the raw event thread through a kfifo. The
size of the event struct is 12 bytes, and space for 512 events is
reserved in the kfifo (6144 bytes), however this is rounded down to 4096
bytes (the next power of 2) by __kfifo_alloc().

4096 bytes is not divisible by 12 therefore if the fifo fills up a third
of a record will be written in the end of the kfifo by
ir_raw_event_store() because the recsize of the fifo is 0 (it doesn't
have records). When this is read by ir_raw_event_thread() a corrupted or
partial record will be read, and in the case of a partial record the
BUG_ON(retval != sizeof(ev)) gets hit too.

According to samples/kfifo/record-example.c struct kfifo_rec_ptr_1 can
handle records of a length between 0 and 255 bytes, so change struct
ir_raw_event_ctrl to use that instead of struct kfifo.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2012-03-08 10:39:53 -03:00

223 lines
5.4 KiB
C

/*
* Remote Controller core raw events header
*
* Copyright (C) 2010 by Mauro Carvalho Chehab <mchehab@redhat.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 version 2 of the License.
*
* 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.
*/
#ifndef _RC_CORE_PRIV
#define _RC_CORE_PRIV
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <media/rc-core.h>
struct ir_raw_handler {
struct list_head list;
u64 protocols; /* which are handled by this handler */
int (*decode)(struct rc_dev *dev, struct ir_raw_event event);
/* These two should only be used by the lirc decoder */
int (*raw_register)(struct rc_dev *dev);
int (*raw_unregister)(struct rc_dev *dev);
};
struct ir_raw_event_ctrl {
struct list_head list; /* to keep track of raw clients */
struct task_struct *thread;
spinlock_t lock;
struct kfifo_rec_ptr_1 kfifo; /* fifo for the pulse/space durations */
ktime_t last_event; /* when last event occurred */
enum raw_event_type last_type; /* last event type */
struct rc_dev *dev; /* pointer to the parent rc_dev */
u64 enabled_protocols; /* enabled raw protocol decoders */
/* raw decoder state follows */
struct ir_raw_event prev_ev;
struct ir_raw_event this_ev;
struct nec_dec {
int state;
unsigned count;
u32 bits;
bool is_nec_x;
bool necx_repeat;
} nec;
struct rc5_dec {
int state;
u32 bits;
unsigned count;
unsigned wanted_bits;
} rc5;
struct rc6_dec {
int state;
u8 header;
u32 body;
bool toggle;
unsigned count;
unsigned wanted_bits;
} rc6;
struct sony_dec {
int state;
u32 bits;
unsigned count;
} sony;
struct jvc_dec {
int state;
u16 bits;
u16 old_bits;
unsigned count;
bool first;
bool toggle;
} jvc;
struct rc5_sz_dec {
int state;
u32 bits;
unsigned count;
unsigned wanted_bits;
} rc5_sz;
struct sanyo_dec {
int state;
unsigned count;
u64 bits;
} sanyo;
struct mce_kbd_dec {
struct input_dev *idev;
struct timer_list rx_timeout;
char name[64];
char phys[64];
int state;
u8 header;
u32 body;
unsigned count;
unsigned wanted_bits;
} mce_kbd;
struct lirc_codec {
struct rc_dev *dev;
struct lirc_driver *drv;
int carrier_low;
ktime_t gap_start;
u64 gap_duration;
bool gap;
bool send_timeout_reports;
} lirc;
};
/* macros for IR decoders */
static inline bool geq_margin(unsigned d1, unsigned d2, unsigned margin)
{
return d1 > (d2 - margin);
}
static inline bool eq_margin(unsigned d1, unsigned d2, unsigned margin)
{
return ((d1 > (d2 - margin)) && (d1 < (d2 + margin)));
}
static inline bool is_transition(struct ir_raw_event *x, struct ir_raw_event *y)
{
return x->pulse != y->pulse;
}
static inline void decrease_duration(struct ir_raw_event *ev, unsigned duration)
{
if (duration > ev->duration)
ev->duration = 0;
else
ev->duration -= duration;
}
/* Returns true if event is normal pulse/space event */
static inline bool is_timing_event(struct ir_raw_event ev)
{
return !ev.carrier_report && !ev.reset;
}
#define TO_US(duration) DIV_ROUND_CLOSEST((duration), 1000)
#define TO_STR(is_pulse) ((is_pulse) ? "pulse" : "space")
/*
* Routines from rc-raw.c to be used internally and by decoders
*/
u64 ir_raw_get_allowed_protocols(void);
int ir_raw_event_register(struct rc_dev *dev);
void ir_raw_event_unregister(struct rc_dev *dev);
int ir_raw_handler_register(struct ir_raw_handler *ir_raw_handler);
void ir_raw_handler_unregister(struct ir_raw_handler *ir_raw_handler);
void ir_raw_init(void);
/*
* Decoder initialization code
*
* Those load logic are called during ir-core init, and automatically
* loads the compiled decoders for their usage with IR raw events
*/
/* from ir-nec-decoder.c */
#ifdef CONFIG_IR_NEC_DECODER_MODULE
#define load_nec_decode() request_module("ir-nec-decoder")
#else
static inline void load_nec_decode(void) { }
#endif
/* from ir-rc5-decoder.c */
#ifdef CONFIG_IR_RC5_DECODER_MODULE
#define load_rc5_decode() request_module("ir-rc5-decoder")
#else
static inline void load_rc5_decode(void) { }
#endif
/* from ir-rc6-decoder.c */
#ifdef CONFIG_IR_RC6_DECODER_MODULE
#define load_rc6_decode() request_module("ir-rc6-decoder")
#else
static inline void load_rc6_decode(void) { }
#endif
/* from ir-jvc-decoder.c */
#ifdef CONFIG_IR_JVC_DECODER_MODULE
#define load_jvc_decode() request_module("ir-jvc-decoder")
#else
static inline void load_jvc_decode(void) { }
#endif
/* from ir-sony-decoder.c */
#ifdef CONFIG_IR_SONY_DECODER_MODULE
#define load_sony_decode() request_module("ir-sony-decoder")
#else
static inline void load_sony_decode(void) { }
#endif
/* from ir-sanyo-decoder.c */
#ifdef CONFIG_IR_SANYO_DECODER_MODULE
#define load_sanyo_decode() request_module("ir-sanyo-decoder")
#else
static inline void load_sanyo_decode(void) { }
#endif
/* from ir-mce_kbd-decoder.c */
#ifdef CONFIG_IR_MCE_KBD_DECODER_MODULE
#define load_mce_kbd_decode() request_module("ir-mce_kbd-decoder")
#else
static inline void load_mce_kbd_decode(void) { }
#endif
/* from ir-lirc-codec.c */
#ifdef CONFIG_IR_LIRC_CODEC_MODULE
#define load_lirc_codec() request_module("ir-lirc-codec")
#else
static inline void load_lirc_codec(void) { }
#endif
#endif /* _RC_CORE_PRIV */