xref: /openbmc/linux/include/sound/cs4271.h (revision c819e2cf)
1 /*
2  * Definitions for CS4271 ASoC codec driver
3  *
4  * Copyright (c) 2010 Alexander Sverdlin <subaparts@yandex.ru>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License
8  * as published by the Free Software Foundation; either version 2
9  * of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  */
16 
17 #ifndef __CS4271_H
18 #define __CS4271_H
19 
20 struct cs4271_platform_data {
21 	int gpio_nreset;	/* GPIO driving Reset pin, if any */
22 	bool amutec_eq_bmutec;	/* flag to enable AMUTEC=BMUTEC */
23 
24 	/*
25 	 * The CS4271 requires its LRCLK and MCLK to be stable before its RESET
26 	 * line is de-asserted. That also means that clocks cannot be changed
27 	 * without putting the chip back into hardware reset, which also requires
28 	 * a complete re-initialization of all registers.
29 	 *
30 	 * One (undocumented) workaround is to assert and de-assert the PDN bit
31 	 * in the MODE2 register. This workaround can be enabled with the
32 	 * following flag.
33 	 *
34 	 * Note that this is not needed in case the clocks are stable
35 	 * throughout the entire runtime of the codec.
36 	 */
37 	bool enable_soft_reset;
38 };
39 
40 #endif /* __CS4271_H */
41