xref: /openbmc/linux/drivers/media/rc/meson-ir.c (revision 3ddc8b84)
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 
53 struct meson_ir {
54 	struct regmap	*reg;
55 	struct rc_dev	*rc;
56 	spinlock_t	lock;
57 };
58 
59 static const struct regmap_config meson_ir_regmap_config = {
60 	.reg_bits = 32,
61 	.val_bits = 32,
62 	.reg_stride = 4,
63 };
64 
65 static 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 
87 static 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 
176 static 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 
187 static 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 
215 static 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 };
221 MODULE_DEVICE_TABLE(of, meson_ir_match);
222 
223 static 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 
233 module_platform_driver(meson_ir_driver);
234 
235 MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver");
236 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
237 MODULE_LICENSE("GPL v2");
238