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 * @dev: The device structure associated with the adc_jack. 30 * @edev: extcon device. 31 * @cable_names: list of supported cables. 32 * @adc_conditions: list of adc value conditions. 33 * @num_conditions: size of adc_conditions. 34 * @irq: irq number of attach/detach event (0 if not exist). 35 * @handling_delay: interrupt handler will schedule extcon event 36 * handling at handling_delay jiffies. 37 * @handler: extcon event handler called by interrupt handler. 38 * @chan: iio channel being queried. 39 * @wakeup_source: Indicates if the device can wake up the system. 40 */ 41 struct adc_jack_data { 42 struct device *dev; 43 struct extcon_dev *edev; 44 45 const unsigned int **cable_names; 46 struct adc_jack_cond *adc_conditions; 47 int num_conditions; 48 49 int irq; 50 unsigned long handling_delay; /* in jiffies */ 51 struct delayed_work handler; 52 53 struct iio_channel *chan; 54 bool wakeup_source; 55 }; 56 57 static void adc_jack_handler(struct work_struct *work) 58 { 59 struct adc_jack_data *data = container_of(to_delayed_work(work), 60 struct adc_jack_data, 61 handler); 62 struct adc_jack_cond *def; 63 int ret, adc_val; 64 int i; 65 66 ret = iio_read_channel_raw(data->chan, &adc_val); 67 if (ret < 0) { 68 dev_err(data->dev, "read channel() error: %d\n", ret); 69 return; 70 } 71 72 /* Get state from adc value with adc_conditions */ 73 for (i = 0; i < data->num_conditions; i++) { 74 def = &data->adc_conditions[i]; 75 if (def->min_adc <= adc_val && def->max_adc >= adc_val) { 76 extcon_set_state_sync(data->edev, def->id, true); 77 return; 78 } 79 } 80 81 /* Set the detached state if adc value is not included in the range */ 82 for (i = 0; i < data->num_conditions; i++) { 83 def = &data->adc_conditions[i]; 84 extcon_set_state_sync(data->edev, def->id, false); 85 } 86 } 87 88 static irqreturn_t adc_jack_irq_thread(int irq, void *_data) 89 { 90 struct adc_jack_data *data = _data; 91 92 queue_delayed_work(system_power_efficient_wq, 93 &data->handler, data->handling_delay); 94 return IRQ_HANDLED; 95 } 96 97 static int adc_jack_probe(struct platform_device *pdev) 98 { 99 struct adc_jack_data *data; 100 struct adc_jack_pdata *pdata = dev_get_platdata(&pdev->dev); 101 int i, err = 0; 102 103 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); 104 if (!data) 105 return -ENOMEM; 106 107 if (!pdata->cable_names) { 108 dev_err(&pdev->dev, "error: cable_names not defined.\n"); 109 return -EINVAL; 110 } 111 112 data->dev = &pdev->dev; 113 data->edev = devm_extcon_dev_allocate(&pdev->dev, pdata->cable_names); 114 if (IS_ERR(data->edev)) { 115 dev_err(&pdev->dev, "failed to allocate extcon device\n"); 116 return -ENOMEM; 117 } 118 119 if (!pdata->adc_conditions) { 120 dev_err(&pdev->dev, "error: adc_conditions not defined.\n"); 121 return -EINVAL; 122 } 123 data->adc_conditions = pdata->adc_conditions; 124 125 /* Check the length of array and set num_conditions */ 126 for (i = 0; data->adc_conditions[i].id != EXTCON_NONE; i++); 127 data->num_conditions = i; 128 129 data->chan = devm_iio_channel_get(&pdev->dev, pdata->consumer_channel); 130 if (IS_ERR(data->chan)) 131 return PTR_ERR(data->chan); 132 133 data->handling_delay = msecs_to_jiffies(pdata->handling_delay_ms); 134 data->wakeup_source = pdata->wakeup_source; 135 136 INIT_DEFERRABLE_WORK(&data->handler, adc_jack_handler); 137 138 platform_set_drvdata(pdev, data); 139 140 err = devm_extcon_dev_register(&pdev->dev, data->edev); 141 if (err) 142 return err; 143 144 data->irq = platform_get_irq(pdev, 0); 145 if (data->irq < 0) 146 return -ENODEV; 147 148 err = request_any_context_irq(data->irq, adc_jack_irq_thread, 149 pdata->irq_flags, pdata->name, data); 150 151 if (err < 0) { 152 dev_err(&pdev->dev, "error: irq %d\n", data->irq); 153 return err; 154 } 155 156 if (data->wakeup_source) 157 device_init_wakeup(&pdev->dev, 1); 158 159 adc_jack_handler(&data->handler.work); 160 return 0; 161 } 162 163 static void adc_jack_remove(struct platform_device *pdev) 164 { 165 struct adc_jack_data *data = platform_get_drvdata(pdev); 166 167 free_irq(data->irq, data); 168 cancel_work_sync(&data->handler.work); 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_new = 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