xref: /openbmc/u-boot/arch/sandbox/include/asm/spi.h (revision 68e80fdda1336068f40915388bbdacfd2b75233a)
1*6122813fSMike Frysinger /*
2*6122813fSMike Frysinger  * Simulate a SPI port and clients (see README.sandbox for details)
3*6122813fSMike Frysinger  *
4*6122813fSMike Frysinger  * Copyright (c) 2011-2013 The Chromium OS Authors.
5*6122813fSMike Frysinger  * See file CREDITS for list of people who contributed to this
6*6122813fSMike Frysinger  * project.
7*6122813fSMike Frysinger  *
8*6122813fSMike Frysinger  * Licensed under the GPL-2 or later.
9*6122813fSMike Frysinger  */
10*6122813fSMike Frysinger 
11*6122813fSMike Frysinger #ifndef __ASM_SPI_H__
12*6122813fSMike Frysinger #define __ASM_SPI_H__
13*6122813fSMike Frysinger 
14*6122813fSMike Frysinger #include <linux/types.h>
15*6122813fSMike Frysinger 
16*6122813fSMike Frysinger /*
17*6122813fSMike Frysinger  * The interface between the SPI bus and the SPI client.  The bus will
18*6122813fSMike Frysinger  * instantiate a client, and that then call into it via these entry
19*6122813fSMike Frysinger  * points.  These should be enough for the client to emulate the SPI
20*6122813fSMike Frysinger  * device just like the real hardware.
21*6122813fSMike Frysinger  */
22*6122813fSMike Frysinger struct sandbox_spi_emu_ops {
23*6122813fSMike Frysinger 	/* The bus wants to instantiate a new client, so setup everything */
24*6122813fSMike Frysinger 	int (*setup)(void **priv, const char *spec);
25*6122813fSMike Frysinger 	/* The bus is done with us, so break things down */
26*6122813fSMike Frysinger 	void (*free)(void *priv);
27*6122813fSMike Frysinger 	/* The CS has been "activated" -- we won't worry about low/high */
28*6122813fSMike Frysinger 	void (*cs_activate)(void *priv);
29*6122813fSMike Frysinger 	/* The CS has been "deactivated" -- we won't worry about low/high */
30*6122813fSMike Frysinger 	void (*cs_deactivate)(void *priv);
31*6122813fSMike Frysinger 	/* The client is rx-ing bytes from the bus, so it should tx some */
32*6122813fSMike Frysinger 	int (*xfer)(void *priv, const u8 *rx, u8 *tx, uint bytes);
33*6122813fSMike Frysinger };
34*6122813fSMike Frysinger 
35*6122813fSMike Frysinger /*
36*6122813fSMike Frysinger  * Extract the bus/cs from the spi spec and return the start of the spi
37*6122813fSMike Frysinger  * client spec.  If the bus/cs are invalid for the current config, then
38*6122813fSMike Frysinger  * it returns NULL.
39*6122813fSMike Frysinger  *
40*6122813fSMike Frysinger  * Example: arg="0:1:foo" will set bus to 0, cs to 1, and return "foo"
41*6122813fSMike Frysinger  */
42*6122813fSMike Frysinger const char *sandbox_spi_parse_spec(const char *arg, unsigned long *bus,
43*6122813fSMike Frysinger 				   unsigned long *cs);
44*6122813fSMike Frysinger 
45*6122813fSMike Frysinger #endif
46