1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * drivers/extcon/extcon-adc-jack.c 4 * 5 * Analog Jack extcon driver with ADC-based detection capability. 6 * 7 * Copyright (C) 2016 Samsung Electronics 8 * Chanwoo Choi <cw00.choi@samsung.com> 9 * 10 * Copyright (C) 2012 Samsung Electronics 11 * MyungJoo Ham <myungjoo.ham@samsung.com> 12 * 13 * Modified for calling to IIO to get adc by <anish.singh@samsung.com> 14 */ 15 16 #include <linux/module.h> 17 #include <linux/slab.h> 18 #include <linux/device.h> 19 #include <linux/platform_device.h> 20 #include <linux/err.h> 21 #include <linux/interrupt.h> 22 #include <linux/workqueue.h> 23 #include <linux/iio/consumer.h> 24 #include <linux/extcon/extcon-adc-jack.h> 25 #include <linux/extcon-provider.h> 26 27 /** 28 * struct adc_jack_data - internal data for adc_jack device driver 29 * @edev: extcon device. 30 * @cable_names: list of supported cables. 31 * @adc_conditions: list of adc value conditions. 32 * @num_conditions: size of adc_conditions. 33 * @irq: irq number of attach/detach event (0 if not exist). 34 * @handling_delay: interrupt handler will schedule extcon event 35 * handling at handling_delay jiffies. 36 * @handler: extcon event handler called by interrupt handler. 37 * @chan: iio channel being queried. 38 */ 39 struct adc_jack_data { 40 struct device *dev; 41 struct extcon_dev *edev; 42 43 const unsigned int **cable_names; 44 struct adc_jack_cond *adc_conditions; 45 int num_conditions; 46 47 int irq; 48 unsigned long handling_delay; /* in jiffies */ 49 struct delayed_work handler; 50 51 struct iio_channel *chan; 52 bool wakeup_source; 53 }; 54 55 static void adc_jack_handler(struct work_struct *work) 56 { 57 struct adc_jack_data *data = container_of(to_delayed_work(work), 58 struct adc_jack_data, 59 handler); 60 struct adc_jack_cond *def; 61 int ret, adc_val; 62 int i; 63 64 ret = iio_read_channel_raw(data->chan, &adc_val); 65 if (ret < 0) { 66 dev_err(data->dev, "read channel() error: %d\n", ret); 67 return; 68 } 69 70 /* Get state from adc value with adc_conditions */ 71 for (i = 0; i < data->num_conditions; i++) { 72 def = &data->adc_conditions[i]; 73 if (def->min_adc <= adc_val && def->max_adc >= adc_val) { 74 extcon_set_state_sync(data->edev, def->id, true); 75 return; 76 } 77 } 78 79 /* Set the detached state if adc value is not included in the range */ 80 for (i = 0; i < data->num_conditions; i++) { 81 def = &data->adc_conditions[i]; 82 extcon_set_state_sync(data->edev, def->id, false); 83 } 84 } 85 86 static irqreturn_t adc_jack_irq_thread(int irq, void *_data) 87 { 88 struct adc_jack_data *data = _data; 89 90 queue_delayed_work(system_power_efficient_wq, 91 &data->handler, data->handling_delay); 92 return IRQ_HANDLED; 93 } 94 95 static int adc_jack_probe(struct platform_device *pdev) 96 { 97 struct adc_jack_data *data; 98 struct adc_jack_pdata *pdata = dev_get_platdata(&pdev->dev); 99 int i, err = 0; 100 101 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); 102 if (!data) 103 return -ENOMEM; 104 105 if (!pdata->cable_names) { 106 dev_err(&pdev->dev, "error: cable_names not defined.\n"); 107 return -EINVAL; 108 } 109 110 data->dev = &pdev->dev; 111 data->edev = devm_extcon_dev_allocate(&pdev->dev, pdata->cable_names); 112 if (IS_ERR(data->edev)) { 113 dev_err(&pdev->dev, "failed to allocate extcon device\n"); 114 return -ENOMEM; 115 } 116 117 if (!pdata->adc_conditions) { 118 dev_err(&pdev->dev, "error: adc_conditions not defined.\n"); 119 return -EINVAL; 120 } 121 data->adc_conditions = pdata->adc_conditions; 122 123 /* Check the length of array and set num_conditions */ 124 for (i = 0; data->adc_conditions[i].id != EXTCON_NONE; i++); 125 data->num_conditions = i; 126 127 data->chan = devm_iio_channel_get(&pdev->dev, pdata->consumer_channel); 128 if (IS_ERR(data->chan)) 129 return PTR_ERR(data->chan); 130 131 data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms); 132 data->wakeup_source = pdata->wakeup_source; 133 134 INIT_DEFERRABLE_WORK(&data->handler, adc_jack_handler); 135 136 platform_set_drvdata(pdev, data); 137 138 err = devm_extcon_dev_register(&pdev->dev, data->edev); 139 if (err) 140 return err; 141 142 data->irq = platform_get_irq(pdev, 0); 143 if (data->irq < 0) 144 return -ENODEV; 145 146 err = request_any_context_irq(data->irq, adc_jack_irq_thread, 147 pdata->irq_flags, pdata->name, data); 148 149 if (err < 0) { 150 dev_err(&pdev->dev, "error: irq %d\n", data->irq); 151 return err; 152 } 153 154 if (data->wakeup_source) 155 device_init_wakeup(&pdev->dev, 1); 156 157 adc_jack_handler(&data->handler.work); 158 return 0; 159 } 160 161 static int adc_jack_remove(struct platform_device *pdev) 162 { 163 struct adc_jack_data *data = platform_get_drvdata(pdev); 164 165 free_irq(data->irq, data); 166 cancel_work_sync(&data->handler.work); 167 168 return 0; 169 } 170 171 #ifdef CONFIG_PM_SLEEP 172 static int adc_jack_suspend(struct device *dev) 173 { 174 struct adc_jack_data *data = dev_get_drvdata(dev); 175 176 cancel_delayed_work_sync(&data->handler); 177 if (device_may_wakeup(data->dev)) 178 enable_irq_wake(data->irq); 179 180 return 0; 181 } 182 183 static int adc_jack_resume(struct device *dev) 184 { 185 struct adc_jack_data *data = dev_get_drvdata(dev); 186 187 if (device_may_wakeup(data->dev)) 188 disable_irq_wake(data->irq); 189 190 return 0; 191 } 192 #endif /* CONFIG_PM_SLEEP */ 193 194 static SIMPLE_DEV_PM_OPS(adc_jack_pm_ops, 195 adc_jack_suspend, adc_jack_resume); 196 197 static struct platform_driver adc_jack_driver = { 198 .probe = adc_jack_probe, 199 .remove = adc_jack_remove, 200 .driver = { 201 .name = "adc-jack", 202 .pm = &adc_jack_pm_ops, 203 }, 204 }; 205 206 module_platform_driver(adc_jack_driver); 207 208 MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>"); 209 MODULE_DESCRIPTION("ADC Jack extcon driver"); 210 MODULE_LICENSE("GPL v2"); 211