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_platform.h>
14 #include <linux/platform_device.h>
15 #include <linux/spinlock.h>
16 #include <linux/bitfield.h>
17
18 #include <media/rc-core.h>
19
20 #define DRIVER_NAME "meson-ir"
21
22 /* valid on all Meson platforms */
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_FRAME 0x14
29 #define IR_DEC_STATUS 0x18
30 #define IR_DEC_REG1 0x1c
31 /* only available on Meson 8b and newer */
32 #define IR_DEC_REG2 0x20
33
34 #define REG0_RATE_MASK GENMASK(11, 0)
35
36 #define DECODE_MODE_NEC 0x0
37 #define DECODE_MODE_RAW 0x2
38
39 /* Meson 6b uses REG1 to configure the mode */
40 #define REG1_MODE_MASK GENMASK(8, 7)
41 #define REG1_MODE_SHIFT 7
42
43 /* Meson 8b / GXBB use REG2 to configure the mode */
44 #define REG2_MODE_MASK GENMASK(3, 0)
45 #define REG2_MODE_SHIFT 0
46
47 #define REG1_TIME_IV_MASK GENMASK(28, 16)
48
49 #define REG1_IRQSEL_MASK GENMASK(3, 2)
50 #define REG1_IRQSEL_NEC_MODE 0
51 #define REG1_IRQSEL_RISE_FALL 1
52 #define REG1_IRQSEL_FALL 2
53 #define REG1_IRQSEL_RISE 3
54
55 #define REG1_RESET BIT(0)
56 #define REG1_ENABLE BIT(15)
57
58 #define STATUS_IR_DEC_IN BIT(8)
59
60 #define MESON_TRATE 10 /* us */
61
62 struct meson_ir {
63 void __iomem *reg;
64 struct rc_dev *rc;
65 spinlock_t lock;
66 };
67
meson_ir_set_mask(struct meson_ir * ir,unsigned int reg,u32 mask,u32 value)68 static void meson_ir_set_mask(struct meson_ir *ir, unsigned int reg,
69 u32 mask, u32 value)
70 {
71 u32 data;
72
73 data = readl(ir->reg + reg);
74 data &= ~mask;
75 data |= (value & mask);
76 writel(data, ir->reg + reg);
77 }
78
meson_ir_irq(int irqno,void * dev_id)79 static irqreturn_t meson_ir_irq(int irqno, void *dev_id)
80 {
81 struct meson_ir *ir = dev_id;
82 u32 duration, status;
83 struct ir_raw_event rawir = {};
84
85 spin_lock(&ir->lock);
86
87 duration = readl_relaxed(ir->reg + IR_DEC_REG1);
88 duration = FIELD_GET(REG1_TIME_IV_MASK, duration);
89 rawir.duration = duration * MESON_TRATE;
90
91 status = readl_relaxed(ir->reg + IR_DEC_STATUS);
92 rawir.pulse = !!(status & STATUS_IR_DEC_IN);
93
94 ir_raw_event_store_with_timeout(ir->rc, &rawir);
95
96 spin_unlock(&ir->lock);
97
98 return IRQ_HANDLED;
99 }
100
meson_ir_probe(struct platform_device * pdev)101 static int meson_ir_probe(struct platform_device *pdev)
102 {
103 struct device *dev = &pdev->dev;
104 struct device_node *node = dev->of_node;
105 struct resource *res;
106 const char *map_name;
107 struct meson_ir *ir;
108 int irq, ret;
109
110 ir = devm_kzalloc(dev, sizeof(struct meson_ir), GFP_KERNEL);
111 if (!ir)
112 return -ENOMEM;
113
114 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
115 ir->reg = devm_ioremap_resource(dev, res);
116 if (IS_ERR(ir->reg))
117 return PTR_ERR(ir->reg);
118
119 irq = platform_get_irq(pdev, 0);
120 if (irq < 0)
121 return irq;
122
123 ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW);
124 if (!ir->rc) {
125 dev_err(dev, "failed to allocate rc device\n");
126 return -ENOMEM;
127 }
128
129 ir->rc->priv = ir;
130 ir->rc->device_name = DRIVER_NAME;
131 ir->rc->input_phys = DRIVER_NAME "/input0";
132 ir->rc->input_id.bustype = BUS_HOST;
133 map_name = of_get_property(node, "linux,rc-map-name", NULL);
134 ir->rc->map_name = map_name ? map_name : RC_MAP_EMPTY;
135 ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
136 ir->rc->rx_resolution = MESON_TRATE;
137 ir->rc->min_timeout = 1;
138 ir->rc->timeout = IR_DEFAULT_TIMEOUT;
139 ir->rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
140 ir->rc->driver_name = DRIVER_NAME;
141
142 spin_lock_init(&ir->lock);
143 platform_set_drvdata(pdev, ir);
144
145 ret = devm_rc_register_device(dev, ir->rc);
146 if (ret) {
147 dev_err(dev, "failed to register rc device\n");
148 return ret;
149 }
150
151 ret = devm_request_irq(dev, irq, meson_ir_irq, 0, NULL, ir);
152 if (ret) {
153 dev_err(dev, "failed to request irq\n");
154 return ret;
155 }
156
157 /* Reset the decoder */
158 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, REG1_RESET);
159 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, 0);
160
161 /* Set general operation mode (= raw/software decoding) */
162 if (of_device_is_compatible(node, "amlogic,meson6-ir"))
163 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK,
164 FIELD_PREP(REG1_MODE_MASK, DECODE_MODE_RAW));
165 else
166 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK,
167 FIELD_PREP(REG2_MODE_MASK, DECODE_MODE_RAW));
168
169 /* Set rate */
170 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, MESON_TRATE - 1);
171 /* IRQ on rising and falling edges */
172 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_IRQSEL_MASK,
173 FIELD_PREP(REG1_IRQSEL_MASK, REG1_IRQSEL_RISE_FALL));
174 /* Enable the decoder */
175 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, REG1_ENABLE);
176
177 dev_info(dev, "receiver initialized\n");
178
179 return 0;
180 }
181
meson_ir_remove(struct platform_device * pdev)182 static int meson_ir_remove(struct platform_device *pdev)
183 {
184 struct meson_ir *ir = platform_get_drvdata(pdev);
185 unsigned long flags;
186
187 /* Disable the decoder */
188 spin_lock_irqsave(&ir->lock, flags);
189 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, 0);
190 spin_unlock_irqrestore(&ir->lock, flags);
191
192 return 0;
193 }
194
meson_ir_shutdown(struct platform_device * pdev)195 static void meson_ir_shutdown(struct platform_device *pdev)
196 {
197 struct device *dev = &pdev->dev;
198 struct device_node *node = dev->of_node;
199 struct meson_ir *ir = platform_get_drvdata(pdev);
200 unsigned long flags;
201
202 spin_lock_irqsave(&ir->lock, flags);
203
204 /*
205 * Set operation mode to NEC/hardware decoding to give
206 * bootloader a chance to power the system back on
207 */
208 if (of_device_is_compatible(node, "amlogic,meson6-ir"))
209 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK,
210 DECODE_MODE_NEC << REG1_MODE_SHIFT);
211 else
212 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK,
213 DECODE_MODE_NEC << REG2_MODE_SHIFT);
214
215 /* Set rate to default value */
216 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, 0x13);
217
218 spin_unlock_irqrestore(&ir->lock, flags);
219 }
220
221 static const struct of_device_id meson_ir_match[] = {
222 { .compatible = "amlogic,meson6-ir" },
223 { .compatible = "amlogic,meson8b-ir" },
224 { .compatible = "amlogic,meson-gxbb-ir" },
225 { },
226 };
227 MODULE_DEVICE_TABLE(of, meson_ir_match);
228
229 static struct platform_driver meson_ir_driver = {
230 .probe = meson_ir_probe,
231 .remove = meson_ir_remove,
232 .shutdown = meson_ir_shutdown,
233 .driver = {
234 .name = DRIVER_NAME,
235 .of_match_table = meson_ir_match,
236 },
237 };
238
239 module_platform_driver(meson_ir_driver);
240
241 MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver");
242 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>");
243 MODULE_LICENSE("GPL v2");
244