1/*-
2 * Copyright (c) 2017 Ian Lepore <ian@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 *
25 * $FreeBSD: stable/11/sys/dev/sdhci/sdhci_fdt_gpio.h 314508 2017-03-01 20:22:25Z ian $
26 */
27
28/*
29 * Support routines usable by any SoC sdhci bridge driver that uses gpio pins
30 * for card detect and/or write protect, and uses FDT data to describe those
31 * pins.  A bridge driver need only supply a couple 2-line forwarding functions
32 * to connect the get_present and get_readonly accessors to the corresponding
33 * driver interface functions, and add setup/teardown calls to its attach and
34 * detach functions.
35 */
36
37#ifndef	_SDHCI_FDT_GPIO_H_
38#define	_SDHCI_FDT_GPIO_H_
39
40struct sdhci_slot;
41struct sdhci_fdt_gpio;
42
43/*
44 * sdhci_fdt_gpio_setup()
45 * sdhci_fdt_gpio_teardown()
46 *
47 * Process FDT properties that use gpio pins and set up interrupt handling (if
48 * supported by hardware) and accessor functions to read the pins.
49 *
50 * Setup cannot fail.  If the properties are not present, the accessors will
51 * return the values from standard sdhci registers.  If the gpio controller
52 * can't trigger interrupts on both edges, it configures the slot to use polling
53 * for card presence detection.  If it can't access the gpio pin at all it sets
54 * up the get_present() accessor to always return true.  Likewise the
55 * get_readonly() accessor always returns false if its pin can't be accessed.
56 */
57struct sdhci_fdt_gpio *sdhci_fdt_gpio_setup(device_t dev, struct sdhci_slot *slot);
58void sdhci_fdt_gpio_teardown(struct sdhci_fdt_gpio *gpio);
59
60/*
61 * sdhci_fdt_gpio_get_present()
62 * sdhci_fdt_gpio_get_readonly()
63 *
64 * Gpio pin state accessor functions.
65 */
66bool sdhci_fdt_gpio_get_present(struct sdhci_fdt_gpio *gpio);
67int  sdhci_fdt_gpio_get_readonly(struct sdhci_fdt_gpio *gpio);
68
69#endif
70