rockbox/firmware/target/arm/imx233/kernel-imx233.h
Amaury Pouly 3210457764 imx233: fix touchscreen driver
One cannot call lradc_acquire in IRQ context. The solution is to reserve the
channel once at init. There is an additional complication on STMP3600 where
channel mapping is fixed.

Change-Id: Idccbac634a4d9002703e2b1d57748beb9b245cbb
2017-05-16 12:14:43 +10:00

46 lines
1.8 KiB
C

/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2011 by Amaury Pouly
*
* 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef __KERNEL_IMX233__
#define __KERNEL_IMX233__
#include "kernel.h"
/* The i.MX233 uses in several places virtual channels to multiplex the work.
* To arbiter the use of the different channels, we use a simple channel arbiter
* based on a semaphore to count the number of channels in use, and a bitmask
* protected by a mutex */
struct channel_arbiter_t
{
struct semaphore sema;
struct mutex mutex;
unsigned free_bm;
int count;
};
void arbiter_init(struct channel_arbiter_t *a, unsigned count);
// doesn't check in use !
void arbiter_reserve(struct channel_arbiter_t *a, unsigned channel);
/* return channel on success and OBJ_WAIT_TIMEOUT on failure */
int arbiter_acquire(struct channel_arbiter_t *a, int timeout);
void arbiter_release(struct channel_arbiter_t *a, int channel);
bool arbiter_acquired(struct channel_arbiter_t *a, int channel);
#endif /* __KERNEL_IMX233__ */