1 /* drivers/media/platform/s5p-cec/s5p_cec.c
3 * Samsung S5P CEC driver
5 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
12 * This driver is based on the "cec interface driver for exynos soc" by
16 #include <linux/clk.h>
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/mfd/syscon.h>
20 #include <linux/module.h>
22 #include <linux/platform_device.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/timer.h>
25 #include <linux/version.h>
26 #include <linux/workqueue.h>
27 #include <media/cec.h>
29 #include "exynos_hdmi_cec.h"
33 #define CEC_NAME "s5p-cec"
36 module_param(debug, int, 0644);
37 MODULE_PARM_DESC(debug, "debug level (0-2)");
39 static int s5p_cec_adap_enable(struct cec_adapter *adap, bool enable)
41 struct s5p_cec_dev *cec = adap->priv;
44 pm_runtime_get_sync(cec->dev);
48 s5p_cec_set_divider(cec);
49 s5p_cec_threshold(cec);
51 s5p_cec_unmask_tx_interrupts(cec);
52 s5p_cec_unmask_rx_interrupts(cec);
53 s5p_cec_enable_rx(cec);
55 s5p_cec_mask_tx_interrupts(cec);
56 s5p_cec_mask_rx_interrupts(cec);
57 pm_runtime_disable(cec->dev);
63 static int s5p_cec_adap_log_addr(struct cec_adapter *adap, u8 addr)
65 struct s5p_cec_dev *cec = adap->priv;
67 s5p_cec_set_addr(cec, addr);
71 static int s5p_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
72 u32 signal_free_time, struct cec_msg *msg)
74 struct s5p_cec_dev *cec = adap->priv;
77 * Unclear if 0 retries are allowed by the hardware, so have 1 as
80 s5p_cec_copy_packet(cec, msg->msg, msg->len, max(1, attempts - 1));
84 static irqreturn_t s5p_cec_irq_handler(int irq, void *priv)
86 struct s5p_cec_dev *cec = priv;
89 status = s5p_cec_get_status(cec);
91 dev_dbg(cec->dev, "irq received\n");
93 if (status & CEC_STATUS_TX_DONE) {
94 if (status & CEC_STATUS_TX_ERROR) {
95 dev_dbg(cec->dev, "CEC_STATUS_TX_ERROR set\n");
96 cec->tx = STATE_ERROR;
98 dev_dbg(cec->dev, "CEC_STATUS_TX_DONE\n");
101 s5p_clr_pending_tx(cec);
104 if (status & CEC_STATUS_RX_DONE) {
105 if (status & CEC_STATUS_RX_ERROR) {
106 dev_dbg(cec->dev, "CEC_STATUS_RX_ERROR set\n");
107 s5p_cec_rx_reset(cec);
108 s5p_cec_enable_rx(cec);
110 dev_dbg(cec->dev, "CEC_STATUS_RX_DONE set\n");
111 if (cec->rx != STATE_IDLE)
112 dev_dbg(cec->dev, "Buffer overrun (worker did not process previous message)\n");
113 cec->rx = STATE_BUSY;
114 cec->msg.len = status >> 24;
115 cec->msg.rx_status = CEC_RX_STATUS_OK;
116 s5p_cec_get_rx_buf(cec, cec->msg.len,
118 cec->rx = STATE_DONE;
119 s5p_cec_enable_rx(cec);
121 /* Clear interrupt pending bit */
122 s5p_clr_pending_rx(cec);
124 return IRQ_WAKE_THREAD;
127 static irqreturn_t s5p_cec_irq_handler_thread(int irq, void *priv)
129 struct s5p_cec_dev *cec = priv;
131 dev_dbg(cec->dev, "irq processing thread\n");
134 cec_transmit_done(cec->adap, CEC_TX_STATUS_OK, 0, 0, 0, 0);
135 cec->tx = STATE_IDLE;
138 cec_transmit_done(cec->adap,
139 CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_ERROR,
141 cec->tx = STATE_IDLE;
144 dev_err(cec->dev, "state set to busy, this should not occur here\n");
152 cec_received_msg(cec->adap, &cec->msg);
153 cec->rx = STATE_IDLE;
162 static const struct cec_adap_ops s5p_cec_adap_ops = {
163 .adap_enable = s5p_cec_adap_enable,
164 .adap_log_addr = s5p_cec_adap_log_addr,
165 .adap_transmit = s5p_cec_adap_transmit,
168 static int s5p_cec_probe(struct platform_device *pdev)
170 struct device *dev = &pdev->dev;
171 struct resource *res;
172 struct s5p_cec_dev *cec;
175 cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL);
181 cec->irq = platform_get_irq(pdev, 0);
185 ret = devm_request_threaded_irq(dev, cec->irq, s5p_cec_irq_handler,
186 s5p_cec_irq_handler_thread, 0, pdev->name, cec);
190 cec->clk = devm_clk_get(dev, "hdmicec");
191 if (IS_ERR(cec->clk))
192 return PTR_ERR(cec->clk);
194 cec->pmu = syscon_regmap_lookup_by_phandle(dev->of_node,
195 "samsung,syscon-phandle");
196 if (IS_ERR(cec->pmu))
197 return -EPROBE_DEFER;
199 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
200 cec->reg = devm_ioremap_resource(dev, res);
201 if (IS_ERR(cec->reg))
202 return PTR_ERR(cec->reg);
204 cec->adap = cec_allocate_adapter(&s5p_cec_adap_ops, cec,
206 CEC_CAP_PHYS_ADDR | CEC_CAP_LOG_ADDRS | CEC_CAP_TRANSMIT |
207 CEC_CAP_PASSTHROUGH | CEC_CAP_RC,
209 ret = PTR_ERR_OR_ZERO(cec->adap);
212 ret = cec_register_adapter(cec->adap);
214 cec_delete_adapter(cec->adap);
218 platform_set_drvdata(pdev, cec);
219 pm_runtime_enable(dev);
221 dev_dbg(dev, "successfuly probed\n");
225 static int s5p_cec_remove(struct platform_device *pdev)
227 struct s5p_cec_dev *cec = platform_get_drvdata(pdev);
229 cec_unregister_adapter(cec->adap);
230 pm_runtime_disable(&pdev->dev);
234 static int s5p_cec_runtime_suspend(struct device *dev)
236 struct s5p_cec_dev *cec = dev_get_drvdata(dev);
238 clk_disable_unprepare(cec->clk);
242 static int s5p_cec_runtime_resume(struct device *dev)
244 struct s5p_cec_dev *cec = dev_get_drvdata(dev);
247 ret = clk_prepare_enable(cec->clk);
253 static int __maybe_unused s5p_cec_suspend(struct device *dev)
255 if (pm_runtime_suspended(dev))
257 return s5p_cec_runtime_suspend(dev);
260 static int __maybe_unused s5p_cec_resume(struct device *dev)
262 if (pm_runtime_suspended(dev))
264 return s5p_cec_runtime_resume(dev);
267 static const struct dev_pm_ops s5p_cec_pm_ops = {
268 SET_SYSTEM_SLEEP_PM_OPS(s5p_cec_suspend, s5p_cec_resume)
269 SET_RUNTIME_PM_OPS(s5p_cec_runtime_suspend, s5p_cec_runtime_resume,
273 static const struct of_device_id s5p_cec_match[] = {
275 .compatible = "samsung,s5p-cec",
280 static struct platform_driver s5p_cec_pdrv = {
281 .probe = s5p_cec_probe,
282 .remove = s5p_cec_remove,
285 .of_match_table = s5p_cec_match,
286 .pm = &s5p_cec_pm_ops,
290 module_platform_driver(s5p_cec_pdrv);
292 MODULE_AUTHOR("Kamil Debski <kamil@wypas.org>");
293 MODULE_LICENSE("GPL");
294 MODULE_DESCRIPTION("Samsung S5P CEC driver");