310 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/* drivers/media/platform/s5p-cec/s5p_cec.c3 *4 * Samsung S5P CEC driver5 *6 * Copyright (c) 2014 Samsung Electronics Co., Ltd.7 *8 * This driver is based on the "cec interface driver for exynos soc" by9 * SangPil Moon.10 */11 12#include <linux/clk.h>13#include <linux/interrupt.h>14#include <linux/kernel.h>15#include <linux/mfd/syscon.h>16#include <linux/module.h>17#include <linux/of.h>18#include <linux/of_platform.h>19#include <linux/platform_device.h>20#include <linux/pm_runtime.h>21#include <linux/timer.h>22#include <linux/workqueue.h>23#include <media/cec.h>24#include <media/cec-notifier.h>25 26#include "exynos_hdmi_cec.h"27#include "regs-cec.h"28#include "s5p_cec.h"29 30#define CEC_NAME "s5p-cec"31 32static int debug;33module_param(debug, int, 0644);34MODULE_PARM_DESC(debug, "debug level (0-2)");35 36static int s5p_cec_adap_enable(struct cec_adapter *adap, bool enable)37{38 int ret;39 struct s5p_cec_dev *cec = cec_get_drvdata(adap);40 41 if (enable) {42 ret = pm_runtime_resume_and_get(cec->dev);43 if (ret < 0)44 return ret;45 46 s5p_cec_reset(cec);47 48 s5p_cec_set_divider(cec);49 s5p_cec_threshold(cec);50 51 s5p_cec_unmask_tx_interrupts(cec);52 s5p_cec_unmask_rx_interrupts(cec);53 s5p_cec_enable_rx(cec);54 } else {55 s5p_cec_mask_tx_interrupts(cec);56 s5p_cec_mask_rx_interrupts(cec);57 pm_runtime_put(cec->dev);58 }59 60 return 0;61}62 63static int s5p_cec_adap_log_addr(struct cec_adapter *adap, u8 addr)64{65 struct s5p_cec_dev *cec = cec_get_drvdata(adap);66 67 s5p_cec_set_addr(cec, addr);68 return 0;69}70 71static int s5p_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,72 u32 signal_free_time, struct cec_msg *msg)73{74 struct s5p_cec_dev *cec = cec_get_drvdata(adap);75 76 /*77 * Unclear if 0 retries are allowed by the hardware, so have 1 as78 * the minimum.79 */80 s5p_cec_copy_packet(cec, msg->msg, msg->len, max(1, attempts - 1));81 return 0;82}83 84static irqreturn_t s5p_cec_irq_handler(int irq, void *priv)85{86 struct s5p_cec_dev *cec = priv;87 u32 status = 0;88 89 status = s5p_cec_get_status(cec);90 91 dev_dbg(cec->dev, "irq received\n");92 93 if (status & CEC_STATUS_TX_DONE) {94 if (status & CEC_STATUS_TX_NACK) {95 dev_dbg(cec->dev, "CEC_STATUS_TX_NACK set\n");96 cec->tx = STATE_NACK;97 } else if (status & CEC_STATUS_TX_ERROR) {98 dev_dbg(cec->dev, "CEC_STATUS_TX_ERROR set\n");99 cec->tx = STATE_ERROR;100 } else {101 dev_dbg(cec->dev, "CEC_STATUS_TX_DONE\n");102 cec->tx = STATE_DONE;103 }104 s5p_clr_pending_tx(cec);105 }106 107 if (status & CEC_STATUS_RX_DONE) {108 if (status & CEC_STATUS_RX_ERROR) {109 dev_dbg(cec->dev, "CEC_STATUS_RX_ERROR set\n");110 s5p_cec_rx_reset(cec);111 s5p_cec_enable_rx(cec);112 } else {113 dev_dbg(cec->dev, "CEC_STATUS_RX_DONE set\n");114 if (cec->rx != STATE_IDLE)115 dev_dbg(cec->dev, "Buffer overrun (worker did not process previous message)\n");116 cec->rx = STATE_BUSY;117 cec->msg.len = status >> 24;118 if (cec->msg.len > CEC_MAX_MSG_SIZE)119 cec->msg.len = CEC_MAX_MSG_SIZE;120 cec->msg.rx_status = CEC_RX_STATUS_OK;121 s5p_cec_get_rx_buf(cec, cec->msg.len,122 cec->msg.msg);123 cec->rx = STATE_DONE;124 s5p_cec_enable_rx(cec);125 }126 /* Clear interrupt pending bit */127 s5p_clr_pending_rx(cec);128 }129 return IRQ_WAKE_THREAD;130}131 132static irqreturn_t s5p_cec_irq_handler_thread(int irq, void *priv)133{134 struct s5p_cec_dev *cec = priv;135 136 dev_dbg(cec->dev, "irq processing thread\n");137 switch (cec->tx) {138 case STATE_DONE:139 cec_transmit_done(cec->adap, CEC_TX_STATUS_OK, 0, 0, 0, 0);140 cec->tx = STATE_IDLE;141 break;142 case STATE_NACK:143 cec_transmit_done(cec->adap,144 CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_NACK,145 0, 1, 0, 0);146 cec->tx = STATE_IDLE;147 break;148 case STATE_ERROR:149 cec_transmit_done(cec->adap,150 CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_ERROR,151 0, 0, 0, 1);152 cec->tx = STATE_IDLE;153 break;154 case STATE_BUSY:155 dev_err(cec->dev, "state set to busy, this should not occur here\n");156 break;157 default:158 break;159 }160 161 switch (cec->rx) {162 case STATE_DONE:163 cec_received_msg(cec->adap, &cec->msg);164 cec->rx = STATE_IDLE;165 break;166 default:167 break;168 }169 170 return IRQ_HANDLED;171}172 173static const struct cec_adap_ops s5p_cec_adap_ops = {174 .adap_enable = s5p_cec_adap_enable,175 .adap_log_addr = s5p_cec_adap_log_addr,176 .adap_transmit = s5p_cec_adap_transmit,177};178 179static int s5p_cec_probe(struct platform_device *pdev)180{181 struct device *dev = &pdev->dev;182 struct device *hdmi_dev;183 struct s5p_cec_dev *cec;184 bool needs_hpd = of_property_read_bool(pdev->dev.of_node, "needs-hpd");185 int ret;186 187 hdmi_dev = cec_notifier_parse_hdmi_phandle(dev);188 189 if (IS_ERR(hdmi_dev))190 return PTR_ERR(hdmi_dev);191 192 cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL);193 if (!cec)194 return -ENOMEM;195 196 cec->dev = dev;197 198 cec->irq = platform_get_irq(pdev, 0);199 if (cec->irq < 0)200 return cec->irq;201 202 ret = devm_request_threaded_irq(dev, cec->irq, s5p_cec_irq_handler,203 s5p_cec_irq_handler_thread, 0, pdev->name, cec);204 if (ret)205 return ret;206 207 cec->clk = devm_clk_get(dev, "hdmicec");208 if (IS_ERR(cec->clk))209 return PTR_ERR(cec->clk);210 211 cec->pmu = syscon_regmap_lookup_by_phandle(dev->of_node,212 "samsung,syscon-phandle");213 if (IS_ERR(cec->pmu))214 return -EPROBE_DEFER;215 216 cec->reg = devm_platform_ioremap_resource(pdev, 0);217 if (IS_ERR(cec->reg))218 return PTR_ERR(cec->reg);219 220 cec->adap = cec_allocate_adapter(&s5p_cec_adap_ops, cec, CEC_NAME,221 CEC_CAP_DEFAULTS | (needs_hpd ? CEC_CAP_NEEDS_HPD : 0) |222 CEC_CAP_CONNECTOR_INFO, 1);223 ret = PTR_ERR_OR_ZERO(cec->adap);224 if (ret)225 return ret;226 227 cec->notifier = cec_notifier_cec_adap_register(hdmi_dev, NULL,228 cec->adap);229 if (!cec->notifier) {230 ret = -ENOMEM;231 goto err_delete_adapter;232 }233 234 ret = cec_register_adapter(cec->adap, &pdev->dev);235 if (ret)236 goto err_notifier;237 238 platform_set_drvdata(pdev, cec);239 pm_runtime_enable(dev);240 241 dev_dbg(dev, "successfully probed\n");242 return 0;243 244err_notifier:245 cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);246 247err_delete_adapter:248 cec_delete_adapter(cec->adap);249 return ret;250}251 252static void s5p_cec_remove(struct platform_device *pdev)253{254 struct s5p_cec_dev *cec = platform_get_drvdata(pdev);255 256 cec_notifier_cec_adap_unregister(cec->notifier, cec->adap);257 cec_unregister_adapter(cec->adap);258 pm_runtime_disable(&pdev->dev);259}260 261static int __maybe_unused s5p_cec_runtime_suspend(struct device *dev)262{263 struct s5p_cec_dev *cec = dev_get_drvdata(dev);264 265 clk_disable_unprepare(cec->clk);266 return 0;267}268 269static int __maybe_unused s5p_cec_runtime_resume(struct device *dev)270{271 struct s5p_cec_dev *cec = dev_get_drvdata(dev);272 int ret;273 274 ret = clk_prepare_enable(cec->clk);275 if (ret < 0)276 return ret;277 return 0;278}279 280static const struct dev_pm_ops s5p_cec_pm_ops = {281 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,282 pm_runtime_force_resume)283 SET_RUNTIME_PM_OPS(s5p_cec_runtime_suspend, s5p_cec_runtime_resume,284 NULL)285};286 287static const struct of_device_id s5p_cec_match[] = {288 {289 .compatible = "samsung,s5p-cec",290 },291 {},292};293MODULE_DEVICE_TABLE(of, s5p_cec_match);294 295static struct platform_driver s5p_cec_pdrv = {296 .probe = s5p_cec_probe,297 .remove_new = s5p_cec_remove,298 .driver = {299 .name = CEC_NAME,300 .of_match_table = s5p_cec_match,301 .pm = &s5p_cec_pm_ops,302 },303};304 305module_platform_driver(s5p_cec_pdrv);306 307MODULE_AUTHOR("Kamil Debski <kamil@wypas.org>");308MODULE_LICENSE("GPL");309MODULE_DESCRIPTION("Samsung S5P CEC driver");310