1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver core interface to the pinctrl subsystem.
4 *
5 * Copyright (C) 2012 ST-Ericsson SA
6 * Written on behalf of Linaro for ST-Ericsson
7 * Based on bits of regulator core, gpio core and clk core
8 *
9 * Author: Linus Walleij <linus.walleij@linaro.org>
10 */
11
12#include <linux/device.h>
13#include <linux/pinctrl/devinfo.h>
14#include <linux/pinctrl/consumer.h>
15#include <linux/slab.h>
16
17/**
18 * pinctrl_bind_pins() - called by the device core before probe
19 * @dev: the device that is just about to probe
20 */
21int pinctrl_bind_pins(struct device *dev)
22{
23	int ret;
24
25	if (dev->of_node_reused)
26		return 0;
27
28	dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL);
29	if (!dev->pins)
30		return -ENOMEM;
31
32	dev->pins->p = devm_pinctrl_get(dev);
33	if (IS_ERR(dev->pins->p)) {
34		dev_dbg(dev, "no pinctrl handle\n");
35		ret = PTR_ERR(dev->pins->p);
36		goto cleanup_alloc;
37	}
38
39	dev->pins->default_state = pinctrl_lookup_state(dev->pins->p,
40					PINCTRL_STATE_DEFAULT);
41	if (IS_ERR(dev->pins->default_state)) {
42		dev_dbg(dev, "no default pinctrl state\n");
43		ret = 0;
44		goto cleanup_get;
45	}
46
47	dev->pins->init_state = pinctrl_lookup_state(dev->pins->p,
48					PINCTRL_STATE_INIT);
49	if (IS_ERR(dev->pins->init_state)) {
50		/* Not supplying this state is perfectly legal */
51		dev_dbg(dev, "no init pinctrl state\n");
52
53		ret = pinctrl_select_state(dev->pins->p,
54					   dev->pins->default_state);
55	} else {
56		ret = pinctrl_select_state(dev->pins->p, dev->pins->init_state);
57	}
58
59	if (ret) {
60		dev_dbg(dev, "failed to activate initial pinctrl state\n");
61		goto cleanup_get;
62	}
63
64#ifdef CONFIG_PM
65	/*
66	 * If power management is enabled, we also look for the optional
67	 * sleep and idle pin states, with semantics as defined in
68	 * <linux/pinctrl/pinctrl-state.h>
69	 */
70	dev->pins->sleep_state = pinctrl_lookup_state(dev->pins->p,
71					PINCTRL_STATE_SLEEP);
72	if (IS_ERR(dev->pins->sleep_state))
73		/* Not supplying this state is perfectly legal */
74		dev_dbg(dev, "no sleep pinctrl state\n");
75
76	dev->pins->idle_state = pinctrl_lookup_state(dev->pins->p,
77					PINCTRL_STATE_IDLE);
78	if (IS_ERR(dev->pins->idle_state))
79		/* Not supplying this state is perfectly legal */
80		dev_dbg(dev, "no idle pinctrl state\n");
81#endif
82
83	return 0;
84
85	/*
86	 * If no pinctrl handle or default state was found for this device,
87	 * let's explicitly free the pin container in the device, there is
88	 * no point in keeping it around.
89	 */
90cleanup_get:
91	devm_pinctrl_put(dev->pins->p);
92cleanup_alloc:
93	devm_kfree(dev, dev->pins);
94	dev->pins = NULL;
95
96	/* Return deferrals */
97	if (ret == -EPROBE_DEFER)
98		return ret;
99	/* Return serious errors */
100	if (ret == -EINVAL)
101		return ret;
102	/* We ignore errors like -ENOENT meaning no pinctrl state */
103
104	return 0;
105}
106