1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for Amlogic Meson IR remote receiver
4 *
5 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com>
6 */
7
8#include <linux/device.h>
9#include <linux/err.h>
10#include <linux/interrupt.h>
11#include <linux/io.h>
12#include <linux/module.h>
13#include <linux/of.h>
14#include <linux/platform_device.h>
15#include <linux/spinlock.h>
16#include <linux/bitfield.h>
17#include <linux/regmap.h>
18
19#include <media/rc-core.h>
20
21#define DRIVER_NAME		"meson-ir"
22
23#define IR_DEC_LDR_ACTIVE	0x00
24#define IR_DEC_LDR_IDLE		0x04
25#define IR_DEC_LDR_REPEAT	0x08
26#define IR_DEC_BIT_0		0x0c
27#define IR_DEC_REG0		0x10
28#define IR_DEC_REG0_BASE_TIME	GENMASK(11, 0)
29#define IR_DEC_FRAME		0x14
30#define IR_DEC_STATUS		0x18
31#define IR_DEC_STATUS_PULSE	BIT(8)
32#define IR_DEC_REG1		0x1c
33#define IR_DEC_REG1_TIME_IV	GENMASK(28, 16)
34#define IR_DEC_REG1_ENABLE	BIT(15)
35#define IR_DEC_REG1_MODE	GENMASK(8, 7)
36#define IR_DEC_REG1_IRQSEL	GENMASK(3, 2)
37#define IR_DEC_REG1_RESET	BIT(0)
38/* The following regs are only available on Meson 8b and newer */
39#define IR_DEC_REG2		0x20
40#define IR_DEC_REG2_MODE	GENMASK(3, 0)
41
42#define DEC_MODE_NEC		0x0
43#define DEC_MODE_RAW		0x2
44
45#define IRQSEL_NEC_MODE		0
46#define IRQSEL_RISE_FALL	1
47#define IRQSEL_FALL		2
48#define IRQSEL_RISE		3
49
50#define MESON_RAW_TRATE		10	/* us */
51#define MESON_HW_TRATE		20	/* us */
52
53struct meson_ir {
54	struct regmap	*reg;
55	struct rc_dev	*rc;
56	spinlock_t	lock;
57};
58
59static const struct regmap_config meson_ir_regmap_config = {
60	.reg_bits = 32,
61	.val_bits = 32,
62	.reg_stride = 4,
63};
64
65static irqreturn_t meson_ir_irq(int irqno, void *dev_id)
66{
67	struct meson_ir *ir = dev_id;
68	u32 duration, status;
69	struct ir_raw_event rawir = {};
70
71	spin_lock(&ir->lock);
72
73	regmap_read(ir->reg, IR_DEC_REG1, &duration);
74	duration = FIELD_GET(IR_DEC_REG1_TIME_IV, duration);
75	rawir.duration = duration * MESON_RAW_TRATE;
76
77	regmap_read(ir->reg, IR_DEC_STATUS, &status);
78	rawir.pulse = !!(status & IR_DEC_STATUS_PULSE);
79
80	ir_raw_event_store_with_timeout(ir->rc, &rawir);
81
82	spin_unlock(&ir->lock);
83
84	return IRQ_HANDLED;
85}
86
87static int meson_ir_probe(struct platform_device *pdev)
88{
89	struct device *dev = &pdev->dev;
90	struct device_node *node = dev->of_node;
91	void __iomem *res_start;
92	const char *map_name;
93	struct meson_ir *ir;
94	int irq, ret;
95
96	ir = devm_kzalloc(dev, sizeof(struct meson_ir), GFP_KERNEL);
97	if (!ir)
98		return -ENOMEM;
99
100	res_start = devm_platform_ioremap_resource(pdev, 0);
101	if (IS_ERR(res_start))
102		return PTR_ERR(res_start);
103
104	ir->reg = devm_regmap_init_mmio(&pdev->dev, res_start,
105					&meson_ir_regmap_config);
106	if (IS_ERR(ir->reg))
107		return PTR_ERR(ir->reg);
108
109	irq = platform_get_irq(pdev, 0);
110	if (irq < 0)
111		return irq;
112
113	ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
114	if (!ir->rc) {
115		dev_err(dev, "failed to allocate rc device\n");
116		return -ENOMEM;
117	}
118
119	ir->rc->priv = ir;
120	ir->rc->device_name = DRIVER_NAME;
121	ir->rc->input_phys = DRIVER_NAME "/input0";
122	ir->rc->input_id.bustype = BUS_HOST;
123	map_name = of_get_property(node, "linux,rc-map-name", NULL);
124	ir->rc->map_name = map_name ? map_name : RC_MAP_EMPTY;
125	ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
126	ir->rc->rx_resolution = MESON_RAW_TRATE;
127	ir->rc->min_timeout = 1;
128	ir->rc->timeout = IR_DEFAULT_TIMEOUT;
129	ir->rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
130	ir->rc->driver_name = DRIVER_NAME;
131
132	spin_lock_init(&ir->lock);
133	platform_set_drvdata(pdev, ir);
134
135	ret = devm_rc_register_device(dev, ir->rc);
136	if (ret) {
137		dev_err(dev, "failed to register rc device\n");
138		return ret;
139	}
140
141	ret = devm_request_irq(dev, irq, meson_ir_irq, 0, NULL, ir);
142	if (ret) {
143		dev_err(dev, "failed to request irq\n");
144		return ret;
145	}
146
147	/* Reset the decoder */
148	regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_RESET,
149			   IR_DEC_REG1_RESET);
150	regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_RESET, 0);
151
152	/* Set general operation mode (= raw/software decoding) */
153	if (of_device_is_compatible(node, "amlogic,meson6-ir"))
154		regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_MODE,
155				   FIELD_PREP(IR_DEC_REG1_MODE, DEC_MODE_RAW));
156	else
157		regmap_update_bits(ir->reg, IR_DEC_REG2, IR_DEC_REG2_MODE,
158				   FIELD_PREP(IR_DEC_REG2_MODE, DEC_MODE_RAW));
159
160	/* Set rate */
161	regmap_update_bits(ir->reg, IR_DEC_REG0, IR_DEC_REG0_BASE_TIME,
162			   FIELD_PREP(IR_DEC_REG0_BASE_TIME,
163				      MESON_RAW_TRATE - 1));
164	/* IRQ on rising and falling edges */
165	regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_IRQSEL,
166			   FIELD_PREP(IR_DEC_REG1_IRQSEL, IRQSEL_RISE_FALL));
167	/* Enable the decoder */
168	regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_ENABLE,
169			   IR_DEC_REG1_ENABLE);
170
171	dev_info(dev, "receiver initialized\n");
172
173	return 0;
174}
175
176static void meson_ir_remove(struct platform_device *pdev)
177{
178	struct meson_ir *ir = platform_get_drvdata(pdev);
179	unsigned long flags;
180
181	/* Disable the decoder */
182	spin_lock_irqsave(&ir->lock, flags);
183	regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_ENABLE, 0);
184	spin_unlock_irqrestore(&ir->lock, flags);
185}
186
187static void meson_ir_shutdown(struct platform_device *pdev)
188{
189	struct device *dev = &pdev->dev;
190	struct device_node *node = dev->of_node;
191	struct meson_ir *ir = platform_get_drvdata(pdev);
192	unsigned long flags;
193
194	spin_lock_irqsave(&ir->lock, flags);
195
196	/*
197	 * Set operation mode to NEC/hardware decoding to give
198	 * bootloader a chance to power the system back on
199	 */
200	if (of_device_is_compatible(node, "amlogic,meson6-ir"))
201		regmap_update_bits(ir->reg, IR_DEC_REG1, IR_DEC_REG1_MODE,
202				   FIELD_PREP(IR_DEC_REG1_MODE, DEC_MODE_NEC));
203	else
204		regmap_update_bits(ir->reg, IR_DEC_REG2, IR_DEC_REG2_MODE,
205				   FIELD_PREP(IR_DEC_REG2_MODE, DEC_MODE_NEC));
206
207	/* Set rate to default value */
208	regmap_update_bits(ir->reg, IR_DEC_REG0, IR_DEC_REG0_BASE_TIME,
209			   FIELD_PREP(IR_DEC_REG0_BASE_TIME,
210				      MESON_HW_TRATE - 1));
211
212	spin_unlock_irqrestore(&ir->lock, flags);
213}
214
215static const struct of_device_id meson_ir_match[] = {
216	{ .compatible = "amlogic,meson6-ir" },
217	{ .compatible = "amlogic,meson8b-ir" },
218	{ .compatible = "amlogic,meson-gxbb-ir" },
219	{ },
220};
221MODULE_DEVICE_TABLE(of, meson_ir_match);
222
223static struct platform_driver meson_ir_driver = {
224	.probe		= meson_ir_probe,
225	.remove_new	= meson_ir_remove,
226	.shutdown	= meson_ir_shutdown,
227	.driver = {
228		.name		= DRIVER_NAME,
229		.of_match_table	= meson_ir_match,
230	},
231};
232
233module_platform_driver(meson_ir_driver);
234
235MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver");
236MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
237MODULE_LICENSE("GPL v2");
238