summaryrefslogtreecommitdiff
path: root/drivers/media/platform/s5p-cec/s5p_cec.c
blob: 8837e2678bdeb3507e4ebce501e5ee58216334ad (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
/* drivers/media/platform/s5p-cec/s5p_cec.c
 *
 * Samsung S5P CEC driver
 *
 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This driver is based on the "cec interface driver for exynos soc" by
 * SangPil Moon.
 */

#include <linux/clk.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <media/cec.h>
#include <media/cec-notifier.h>

#include "exynos_hdmi_cec.h"
#include "regs-cec.h"
#include "s5p_cec.h"

#define CEC_NAME	"s5p-cec"

static int debug;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "debug level (0-2)");

static int s5p_cec_adap_enable(struct cec_adapter *adap, bool enable)
{
	struct s5p_cec_dev *cec = cec_get_drvdata(adap);

	if (enable) {
		pm_runtime_get_sync(cec->dev);

		s5p_cec_reset(cec);

		s5p_cec_set_divider(cec);
		s5p_cec_threshold(cec);

		s5p_cec_unmask_tx_interrupts(cec);
		s5p_cec_unmask_rx_interrupts(cec);
		s5p_cec_enable_rx(cec);
	} else {
		s5p_cec_mask_tx_interrupts(cec);
		s5p_cec_mask_rx_interrupts(cec);
		pm_runtime_disable(cec->dev);
	}

	return 0;
}

static int s5p_cec_adap_log_addr(struct cec_adapter *adap, u8 addr)
{
	struct s5p_cec_dev *cec = cec_get_drvdata(adap);

	s5p_cec_set_addr(cec, addr);
	return 0;
}

static int s5p_cec_adap_transmit(struct cec_adapter *adap, u8 attempts,
				 u32 signal_free_time, struct cec_msg *msg)
{
	struct s5p_cec_dev *cec = cec_get_drvdata(adap);

	/*
	 * Unclear if 0 retries are allowed by the hardware, so have 1 as
	 * the minimum.
	 */
	s5p_cec_copy_packet(cec, msg->msg, msg->len, max(1, attempts - 1));
	return 0;
}

static irqreturn_t s5p_cec_irq_handler(int irq, void *priv)
{
	struct s5p_cec_dev *cec = priv;
	u32 status = 0;

	status = s5p_cec_get_status(cec);

	dev_dbg(cec->dev, "irq received\n");

	if (status & CEC_STATUS_TX_DONE) {
		if (status & CEC_STATUS_TX_NACK) {
			dev_dbg(cec->dev, "CEC_STATUS_TX_NACK set\n");
			cec->tx = STATE_NACK;
		} else if (status & CEC_STATUS_TX_ERROR) {
			dev_dbg(cec->dev, "CEC_STATUS_TX_ERROR set\n");
			cec->tx = STATE_ERROR;
		} else {
			dev_dbg(cec->dev, "CEC_STATUS_TX_DONE\n");
			cec->tx = STATE_DONE;
		}
		s5p_clr_pending_tx(cec);
	}

	if (status & CEC_STATUS_RX_DONE) {
		if (status & CEC_STATUS_RX_ERROR) {
			dev_dbg(cec->dev, "CEC_STATUS_RX_ERROR set\n");
			s5p_cec_rx_reset(cec);
			s5p_cec_enable_rx(cec);
		} else {
			dev_dbg(cec->dev, "CEC_STATUS_RX_DONE set\n");
			if (cec->rx != STATE_IDLE)
				dev_dbg(cec->dev, "Buffer overrun (worker did not process previous message)\n");
			cec->rx = STATE_BUSY;
			cec->msg.len = status >> 24;
			cec->msg.rx_status = CEC_RX_STATUS_OK;
			s5p_cec_get_rx_buf(cec, cec->msg.len,
					cec->msg.msg);
			cec->rx = STATE_DONE;
			s5p_cec_enable_rx(cec);
		}
		/* Clear interrupt pending bit */
		s5p_clr_pending_rx(cec);
	}
	return IRQ_WAKE_THREAD;
}

static irqreturn_t s5p_cec_irq_handler_thread(int irq, void *priv)
{
	struct s5p_cec_dev *cec = priv;

	dev_dbg(cec->dev, "irq processing thread\n");
	switch (cec->tx) {
	case STATE_DONE:
		cec_transmit_done(cec->adap, CEC_TX_STATUS_OK, 0, 0, 0, 0);
		cec->tx = STATE_IDLE;
		break;
	case STATE_NACK:
		cec_transmit_done(cec->adap,
			CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_NACK,
			0, 1, 0, 0);
		cec->tx = STATE_IDLE;
		break;
	case STATE_ERROR:
		cec_transmit_done(cec->adap,
			CEC_TX_STATUS_MAX_RETRIES | CEC_TX_STATUS_ERROR,
			0, 0, 0, 1);
		cec->tx = STATE_IDLE;
		break;
	case STATE_BUSY:
		dev_err(cec->dev, "state set to busy, this should not occur here\n");
		break;
	default:
		break;
	}

	switch (cec->rx) {
	case STATE_DONE:
		cec_received_msg(cec->adap, &cec->msg);
		cec->rx = STATE_IDLE;
		break;
	default:
		break;
	}

	return IRQ_HANDLED;
}

static const struct cec_adap_ops s5p_cec_adap_ops = {
	.adap_enable = s5p_cec_adap_enable,
	.adap_log_addr = s5p_cec_adap_log_addr,
	.adap_transmit = s5p_cec_adap_transmit,
};

static int s5p_cec_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *np;
	struct platform_device *hdmi_dev;
	struct resource *res;
	struct s5p_cec_dev *cec;
	bool needs_hpd = of_property_read_bool(pdev->dev.of_node, "needs-hpd");
	int ret;

	np = of_parse_phandle(pdev->dev.of_node, "hdmi-phandle", 0);

	if (!np) {
		dev_err(&pdev->dev, "Failed to find hdmi node in device tree\n");
		return -ENODEV;
	}
	hdmi_dev = of_find_device_by_node(np);
	if (hdmi_dev == NULL)
		return -EPROBE_DEFER;

	cec = devm_kzalloc(&pdev->dev, sizeof(*cec), GFP_KERNEL);
	if (!cec)
		return -ENOMEM;

	cec->dev = dev;

	cec->irq = platform_get_irq(pdev, 0);
	if (cec->irq < 0)
		return cec->irq;

	ret = devm_request_threaded_irq(dev, cec->irq, s5p_cec_irq_handler,
		s5p_cec_irq_handler_thread, 0, pdev->name, cec);
	if (ret)
		return ret;

	cec->clk = devm_clk_get(dev, "hdmicec");
	if (IS_ERR(cec->clk))
		return PTR_ERR(cec->clk);

	cec->pmu = syscon_regmap_lookup_by_phandle(dev->of_node,
						 "samsung,syscon-phandle");
	if (IS_ERR(cec->pmu))
		return -EPROBE_DEFER;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	cec->reg = devm_ioremap_resource(dev, res);
	if (IS_ERR(cec->reg))
		return PTR_ERR(cec->reg);

	cec->notifier = cec_notifier_get(&hdmi_dev->dev);
	if (cec->notifier == NULL)
		return -ENOMEM;

	cec->adap = cec_allocate_adapter(&s5p_cec_adap_ops, cec, CEC_NAME,
		CEC_CAP_DEFAULTS | (needs_hpd ? CEC_CAP_NEEDS_HPD : 0), 1);
	ret = PTR_ERR_OR_ZERO(cec->adap);
	if (ret)
		return ret;

	ret = cec_register_adapter(cec->adap, &pdev->dev);
	if (ret)
		goto err_delete_adapter;

	cec_register_cec_notifier(cec->adap, cec->notifier);

	platform_set_drvdata(pdev, cec);
	pm_runtime_enable(dev);

	dev_dbg(dev, "successfully probed\n");
	return 0;

err_delete_adapter:
	cec_delete_adapter(cec->adap);
	return ret;
}

static int s5p_cec_remove(struct platform_device *pdev)
{
	struct s5p_cec_dev *cec = platform_get_drvdata(pdev);

	cec_unregister_adapter(cec->adap);
	cec_notifier_put(cec->notifier);
	pm_runtime_disable(&pdev->dev);
	return 0;
}

static int __maybe_unused s5p_cec_runtime_suspend(struct device *dev)
{
	struct s5p_cec_dev *cec = dev_get_drvdata(dev);

	clk_disable_unprepare(cec->clk);
	return 0;
}

static int __maybe_unused s5p_cec_runtime_resume(struct device *dev)
{
	struct s5p_cec_dev *cec = dev_get_drvdata(dev);
	int ret;

	ret = clk_prepare_enable(cec->clk);
	if (ret < 0)
		return ret;
	return 0;
}

static const struct dev_pm_ops s5p_cec_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
				pm_runtime_force_resume)
	SET_RUNTIME_PM_OPS(s5p_cec_runtime_suspend, s5p_cec_runtime_resume,
			   NULL)
};

static const struct of_device_id s5p_cec_match[] = {
	{
		.compatible	= "samsung,s5p-cec",
	},
	{},
};
MODULE_DEVICE_TABLE(of, s5p_cec_match);

static struct platform_driver s5p_cec_pdrv = {
	.probe	= s5p_cec_probe,
	.remove	= s5p_cec_remove,
	.driver	= {
		.name		= CEC_NAME,
		.of_match_table	= s5p_cec_match,
		.pm		= &s5p_cec_pm_ops,
	},
};

module_platform_driver(s5p_cec_pdrv);

MODULE_AUTHOR("Kamil Debski <kamil@wypas.org>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Samsung S5P CEC driver");