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 #include "base.h" 18 19 /** 20 * pinctrl_bind_pins() - called by the device core before probe 21 * @dev: the device that is just about to probe 22 */ 23 int pinctrl_bind_pins(struct device *dev) 24 { 25 int ret; 26 27 if (dev->of_node_reused) 28 return 0; 29 30 dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL); 31 if (!dev->pins) 32 return -ENOMEM; 33 34 dev->pins->p = devm_pinctrl_get(dev); 35 if (IS_ERR(dev->pins->p)) { 36 dev_dbg(dev, "no pinctrl handle\n"); 37 ret = PTR_ERR(dev->pins->p); 38 goto cleanup_alloc; 39 } 40 41 dev->pins->default_state = pinctrl_lookup_state(dev->pins->p, 42 PINCTRL_STATE_DEFAULT); 43 if (IS_ERR(dev->pins->default_state)) { 44 dev_dbg(dev, "no default pinctrl state\n"); 45 ret = 0; 46 goto cleanup_get; 47 } 48 49 dev->pins->init_state = pinctrl_lookup_state(dev->pins->p, 50 PINCTRL_STATE_INIT); 51 if (IS_ERR(dev->pins->init_state)) { 52 /* Not supplying this state is perfectly legal */ 53 dev_dbg(dev, "no init pinctrl state\n"); 54 55 ret = pinctrl_select_state(dev->pins->p, 56 dev->pins->default_state); 57 } else { 58 ret = pinctrl_select_state(dev->pins->p, dev->pins->init_state); 59 } 60 61 if (ret) { 62 dev_dbg(dev, "failed to activate initial pinctrl state\n"); 63 goto cleanup_get; 64 } 65 66 #ifdef CONFIG_PM 67 /* 68 * If power management is enabled, we also look for the optional 69 * sleep and idle pin states, with semantics as defined in 70 * <linux/pinctrl/pinctrl-state.h> 71 */ 72 dev->pins->sleep_state = pinctrl_lookup_state(dev->pins->p, 73 PINCTRL_STATE_SLEEP); 74 if (IS_ERR(dev->pins->sleep_state)) 75 /* Not supplying this state is perfectly legal */ 76 dev_dbg(dev, "no sleep pinctrl state\n"); 77 78 dev->pins->idle_state = pinctrl_lookup_state(dev->pins->p, 79 PINCTRL_STATE_IDLE); 80 if (IS_ERR(dev->pins->idle_state)) 81 /* Not supplying this state is perfectly legal */ 82 dev_dbg(dev, "no idle pinctrl state\n"); 83 #endif 84 85 return 0; 86 87 /* 88 * If no pinctrl handle or default state was found for this device, 89 * let's explicitly free the pin container in the device, there is 90 * no point in keeping it around. 91 */ 92 cleanup_get: 93 devm_pinctrl_put(dev->pins->p); 94 cleanup_alloc: 95 devm_kfree(dev, dev->pins); 96 dev->pins = NULL; 97 98 /* Return deferrals */ 99 if (ret == -EPROBE_DEFER) 100 return ret; 101 /* Return serious errors */ 102 if (ret == -EINVAL) 103 return ret; 104 /* We ignore errors like -ENOENT meaning no pinctrl state */ 105 106 return 0; 107 } 108