1/*
2 * Driver core interface to the pinctrl subsystem.
3 *
4 * Copyright (C) 2012 ST-Ericsson SA
5 * Written on behalf of Linaro for ST-Ericsson
6 * Based on bits of regulator core, gpio core and clk core
7 *
8 * Author: Linus Walleij <linus.walleij@linaro.org>
9 *
10 * License terms: GNU General Public License (GPL) version 2
11 */
12
13#include <linux/device.h>
14#include <linux/pinctrl/devinfo.h>
15#include <linux/pinctrl/consumer.h>
16#include <linux/slab.h>
17
18/**
19 * pinctrl_bind_pins() - called by the device core before probe
20 * @dev: the device that is just about to probe
21 */
22int pinctrl_bind_pins(struct device *dev)
23{
24	int ret;
25
26	dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL);
27	if (!dev->pins)
28		return -ENOMEM;
29
30	dev->pins->p = devm_pinctrl_get(dev);
31	if (IS_ERR(dev->pins->p)) {
32		dev_dbg(dev, "no pinctrl handle\n");
33		ret = PTR_ERR(dev->pins->p);
34		goto cleanup_alloc;
35	}
36
37	dev->pins->default_state = pinctrl_lookup_state(dev->pins->p,
38					PINCTRL_STATE_DEFAULT);
39	if (IS_ERR(dev->pins->default_state)) {
40		dev_dbg(dev, "no default pinctrl state\n");
41		ret = 0;
42		goto cleanup_get;
43	}
44
45	ret = pinctrl_select_state(dev->pins->p, dev->pins->default_state);
46	if (ret) {
47		dev_dbg(dev, "failed to activate default pinctrl state\n");
48		goto cleanup_get;
49	}
50
51#ifdef CONFIG_PM
52	/*
53	 * If power management is enabled, we also look for the optional
54	 * sleep and idle pin states, with semantics as defined in
55	 * <linux/pinctrl/pinctrl-state.h>
56	 */
57	dev->pins->sleep_state = pinctrl_lookup_state(dev->pins->p,
58					PINCTRL_STATE_SLEEP);
59	if (IS_ERR(dev->pins->sleep_state))
60		/* Not supplying this state is perfectly legal */
61		dev_dbg(dev, "no sleep pinctrl state\n");
62
63	dev->pins->idle_state = pinctrl_lookup_state(dev->pins->p,
64					PINCTRL_STATE_IDLE);
65	if (IS_ERR(dev->pins->idle_state))
66		/* Not supplying this state is perfectly legal */
67		dev_dbg(dev, "no idle pinctrl state\n");
68#endif
69
70	return 0;
71
72	/*
73	 * If no pinctrl handle or default state was found for this device,
74	 * let's explicitly free the pin container in the device, there is
75	 * no point in keeping it around.
76	 */
77cleanup_get:
78	devm_pinctrl_put(dev->pins->p);
79cleanup_alloc:
80	devm_kfree(dev, dev->pins);
81	dev->pins = NULL;
82
83	/* Only return deferrals */
84	if (ret != -EPROBE_DEFER)
85		ret = 0;
86
87	return ret;
88}
89