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
meson_ir_irq(int irqno,void * dev_id)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
meson_ir_probe(struct platform_device * pdev)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
meson_ir_remove(struct platform_device * pdev)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
meson_ir_shutdown(struct platform_device * pdev)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