294 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright 2017 Cisco Systems, Inc. and/or its affiliates. All rights reserved.4 */5 6#include <linux/module.h>7#include <linux/interrupt.h>8#include <linux/delay.h>9#include <linux/platform_device.h>10#include <linux/gpio/consumer.h>11#include <media/cec-notifier.h>12#include <media/cec-pin.h>13 14struct cec_gpio {15 struct cec_adapter *adap;16 struct cec_notifier *notifier;17 struct device *dev;18 19 struct gpio_desc *cec_gpio;20 int cec_irq;21 bool cec_is_low;22 23 struct gpio_desc *hpd_gpio;24 int hpd_irq;25 bool hpd_is_high;26 ktime_t hpd_ts;27 28 struct gpio_desc *v5_gpio;29 int v5_irq;30 bool v5_is_high;31 ktime_t v5_ts;32};33 34static int cec_gpio_read(struct cec_adapter *adap)35{36 struct cec_gpio *cec = cec_get_drvdata(adap);37 38 if (cec->cec_is_low)39 return 0;40 return gpiod_get_value(cec->cec_gpio);41}42 43static void cec_gpio_high(struct cec_adapter *adap)44{45 struct cec_gpio *cec = cec_get_drvdata(adap);46 47 if (!cec->cec_is_low)48 return;49 cec->cec_is_low = false;50 gpiod_set_value(cec->cec_gpio, 1);51}52 53static void cec_gpio_low(struct cec_adapter *adap)54{55 struct cec_gpio *cec = cec_get_drvdata(adap);56 57 if (cec->cec_is_low)58 return;59 cec->cec_is_low = true;60 gpiod_set_value(cec->cec_gpio, 0);61}62 63static irqreturn_t cec_hpd_gpio_irq_handler_thread(int irq, void *priv)64{65 struct cec_gpio *cec = priv;66 67 cec_queue_pin_hpd_event(cec->adap, cec->hpd_is_high, cec->hpd_ts);68 return IRQ_HANDLED;69}70 71static irqreturn_t cec_5v_gpio_irq_handler(int irq, void *priv)72{73 struct cec_gpio *cec = priv;74 int val = gpiod_get_value(cec->v5_gpio);75 bool is_high = val > 0;76 77 if (val < 0 || is_high == cec->v5_is_high)78 return IRQ_HANDLED;79 cec->v5_ts = ktime_get();80 cec->v5_is_high = is_high;81 return IRQ_WAKE_THREAD;82}83 84static irqreturn_t cec_5v_gpio_irq_handler_thread(int irq, void *priv)85{86 struct cec_gpio *cec = priv;87 88 cec_queue_pin_5v_event(cec->adap, cec->v5_is_high, cec->v5_ts);89 return IRQ_HANDLED;90}91 92static irqreturn_t cec_hpd_gpio_irq_handler(int irq, void *priv)93{94 struct cec_gpio *cec = priv;95 int val = gpiod_get_value(cec->hpd_gpio);96 bool is_high = val > 0;97 98 if (val < 0 || is_high == cec->hpd_is_high)99 return IRQ_HANDLED;100 cec->hpd_ts = ktime_get();101 cec->hpd_is_high = is_high;102 return IRQ_WAKE_THREAD;103}104 105static irqreturn_t cec_gpio_irq_handler(int irq, void *priv)106{107 struct cec_gpio *cec = priv;108 int val = gpiod_get_value(cec->cec_gpio);109 110 if (val >= 0)111 cec_pin_changed(cec->adap, val > 0);112 return IRQ_HANDLED;113}114 115static bool cec_gpio_enable_irq(struct cec_adapter *adap)116{117 struct cec_gpio *cec = cec_get_drvdata(adap);118 119 enable_irq(cec->cec_irq);120 return true;121}122 123static void cec_gpio_disable_irq(struct cec_adapter *adap)124{125 struct cec_gpio *cec = cec_get_drvdata(adap);126 127 disable_irq(cec->cec_irq);128}129 130static void cec_gpio_status(struct cec_adapter *adap, struct seq_file *file)131{132 struct cec_gpio *cec = cec_get_drvdata(adap);133 134 seq_printf(file, "mode: %s\n", cec->cec_is_low ? "low-drive" : "read");135 seq_printf(file, "using irq: %d\n", cec->cec_irq);136 if (cec->hpd_gpio)137 seq_printf(file, "hpd: %s\n",138 cec->hpd_is_high ? "high" : "low");139 if (cec->v5_gpio)140 seq_printf(file, "5V: %s\n",141 cec->v5_is_high ? "high" : "low");142}143 144static int cec_gpio_read_hpd(struct cec_adapter *adap)145{146 struct cec_gpio *cec = cec_get_drvdata(adap);147 148 if (!cec->hpd_gpio)149 return -ENOTTY;150 return gpiod_get_value(cec->hpd_gpio);151}152 153static int cec_gpio_read_5v(struct cec_adapter *adap)154{155 struct cec_gpio *cec = cec_get_drvdata(adap);156 157 if (!cec->v5_gpio)158 return -ENOTTY;159 return gpiod_get_value(cec->v5_gpio);160}161 162static const struct cec_pin_ops cec_gpio_pin_ops = {163 .read = cec_gpio_read,164 .low = cec_gpio_low,165 .high = cec_gpio_high,166 .enable_irq = cec_gpio_enable_irq,167 .disable_irq = cec_gpio_disable_irq,168 .status = cec_gpio_status,169 .read_hpd = cec_gpio_read_hpd,170 .read_5v = cec_gpio_read_5v,171};172 173static int cec_gpio_probe(struct platform_device *pdev)174{175 struct device *dev = &pdev->dev;176 struct device *hdmi_dev;177 struct cec_gpio *cec;178 u32 caps = CEC_CAP_DEFAULTS | CEC_CAP_MONITOR_ALL | CEC_CAP_MONITOR_PIN;179 int ret;180 181 hdmi_dev = cec_notifier_parse_hdmi_phandle(dev);182 if (PTR_ERR(hdmi_dev) == -EPROBE_DEFER)183 return PTR_ERR(hdmi_dev);184 if (IS_ERR(hdmi_dev))185 caps |= CEC_CAP_PHYS_ADDR;186 187 cec = devm_kzalloc(dev, sizeof(*cec), GFP_KERNEL);188 if (!cec)189 return -ENOMEM;190 191 cec->dev = dev;192 193 cec->cec_gpio = devm_gpiod_get(dev, "cec", GPIOD_OUT_HIGH_OPEN_DRAIN);194 if (IS_ERR(cec->cec_gpio))195 return PTR_ERR(cec->cec_gpio);196 cec->cec_irq = gpiod_to_irq(cec->cec_gpio);197 198 cec->hpd_gpio = devm_gpiod_get_optional(dev, "hpd", GPIOD_IN);199 if (IS_ERR(cec->hpd_gpio))200 return PTR_ERR(cec->hpd_gpio);201 202 cec->v5_gpio = devm_gpiod_get_optional(dev, "v5", GPIOD_IN);203 if (IS_ERR(cec->v5_gpio))204 return PTR_ERR(cec->v5_gpio);205 206 cec->adap = cec_pin_allocate_adapter(&cec_gpio_pin_ops,207 cec, pdev->name, caps);208 if (IS_ERR(cec->adap))209 return PTR_ERR(cec->adap);210 211 ret = devm_request_irq(dev, cec->cec_irq, cec_gpio_irq_handler,212 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_NO_AUTOEN,213 cec->adap->name, cec);214 if (ret)215 goto del_adap;216 217 if (cec->hpd_gpio) {218 cec->hpd_irq = gpiod_to_irq(cec->hpd_gpio);219 ret = devm_request_threaded_irq(dev, cec->hpd_irq,220 cec_hpd_gpio_irq_handler,221 cec_hpd_gpio_irq_handler_thread,222 IRQF_ONESHOT |223 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,224 "hpd-gpio", cec);225 if (ret)226 goto del_adap;227 }228 229 if (cec->v5_gpio) {230 cec->v5_irq = gpiod_to_irq(cec->v5_gpio);231 ret = devm_request_threaded_irq(dev, cec->v5_irq,232 cec_5v_gpio_irq_handler,233 cec_5v_gpio_irq_handler_thread,234 IRQF_ONESHOT |235 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,236 "v5-gpio", cec);237 if (ret)238 goto del_adap;239 }240 241 if (!IS_ERR(hdmi_dev)) {242 cec->notifier = cec_notifier_cec_adap_register(hdmi_dev, NULL,243 cec->adap);244 if (!cec->notifier) {245 ret = -ENOMEM;246 goto del_adap;247 }248 }249 250 ret = cec_register_adapter(cec->adap, &pdev->dev);251 if (ret)252 goto unreg_notifier;253 254 platform_set_drvdata(pdev, cec);255 return 0;256 257unreg_notifier:258 cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);259del_adap:260 cec_delete_adapter(cec->adap);261 return ret;262}263 264static void cec_gpio_remove(struct platform_device *pdev)265{266 struct cec_gpio *cec = platform_get_drvdata(pdev);267 268 cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);269 cec_unregister_adapter(cec->adap);270}271 272static const struct of_device_id cec_gpio_match[] = {273 {274 .compatible = "cec-gpio",275 },276 {},277};278MODULE_DEVICE_TABLE(of, cec_gpio_match);279 280static struct platform_driver cec_gpio_pdrv = {281 .probe = cec_gpio_probe,282 .remove_new = cec_gpio_remove,283 .driver = {284 .name = "cec-gpio",285 .of_match_table = cec_gpio_match,286 },287};288 289module_platform_driver(cec_gpio_pdrv);290 291MODULE_AUTHOR("Hans Verkuil <hans.verkuil@cisco.com>");292MODULE_LICENSE("GPL v2");293MODULE_DESCRIPTION("CEC GPIO driver");294