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 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 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 = US_TO_NS(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 } 100 101 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 dev_err(dev, "no irq resource\n"); 122 return irq; 123 } 124 125 ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW); 126 if (!ir->rc) { 127 dev_err(dev, "failed to allocate rc device\n"); 128 return -ENOMEM; 129 } 130 131 ir->rc->priv = ir; 132 ir->rc->device_name = DRIVER_NAME; 133 ir->rc->input_phys = DRIVER_NAME "/input0"; 134 ir->rc->input_id.bustype = BUS_HOST; 135 map_name = of_get_property(node, "linux,rc-map-name", NULL); 136 ir->rc->map_name = map_name ? map_name : RC_MAP_EMPTY; 137 ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER; 138 ir->rc->rx_resolution = US_TO_NS(MESON_TRATE); 139 ir->rc->min_timeout = 1; 140 ir->rc->timeout = IR_DEFAULT_TIMEOUT; 141 ir->rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT; 142 ir->rc->driver_name = DRIVER_NAME; 143 144 spin_lock_init(&ir->lock); 145 platform_set_drvdata(pdev, ir); 146 147 ret = devm_rc_register_device(dev, ir->rc); 148 if (ret) { 149 dev_err(dev, "failed to register rc device\n"); 150 return ret; 151 } 152 153 ret = devm_request_irq(dev, irq, meson_ir_irq, 0, NULL, ir); 154 if (ret) { 155 dev_err(dev, "failed to request irq\n"); 156 return ret; 157 } 158 159 /* Reset the decoder */ 160 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, REG1_RESET); 161 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, 0); 162 163 /* Set general operation mode (= raw/software decoding) */ 164 if (of_device_is_compatible(node, "amlogic,meson6-ir")) 165 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK, 166 FIELD_PREP(REG1_MODE_MASK, DECODE_MODE_RAW)); 167 else 168 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK, 169 FIELD_PREP(REG2_MODE_MASK, DECODE_MODE_RAW)); 170 171 /* Set rate */ 172 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, MESON_TRATE - 1); 173 /* IRQ on rising and falling edges */ 174 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_IRQSEL_MASK, 175 FIELD_PREP(REG1_IRQSEL_MASK, REG1_IRQSEL_RISE_FALL)); 176 /* Enable the decoder */ 177 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, REG1_ENABLE); 178 179 dev_info(dev, "receiver initialized\n"); 180 181 return 0; 182 } 183 184 static int meson_ir_remove(struct platform_device *pdev) 185 { 186 struct meson_ir *ir = platform_get_drvdata(pdev); 187 unsigned long flags; 188 189 /* Disable the decoder */ 190 spin_lock_irqsave(&ir->lock, flags); 191 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, 0); 192 spin_unlock_irqrestore(&ir->lock, flags); 193 194 return 0; 195 } 196 197 static void meson_ir_shutdown(struct platform_device *pdev) 198 { 199 struct device *dev = &pdev->dev; 200 struct device_node *node = dev->of_node; 201 struct meson_ir *ir = platform_get_drvdata(pdev); 202 unsigned long flags; 203 204 spin_lock_irqsave(&ir->lock, flags); 205 206 /* 207 * Set operation mode to NEC/hardware decoding to give 208 * bootloader a chance to power the system back on 209 */ 210 if (of_device_is_compatible(node, "amlogic,meson6-ir")) 211 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK, 212 DECODE_MODE_NEC << REG1_MODE_SHIFT); 213 else 214 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK, 215 DECODE_MODE_NEC << REG2_MODE_SHIFT); 216 217 /* Set rate to default value */ 218 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, 0x13); 219 220 spin_unlock_irqrestore(&ir->lock, flags); 221 } 222 223 static const struct of_device_id meson_ir_match[] = { 224 { .compatible = "amlogic,meson6-ir" }, 225 { .compatible = "amlogic,meson8b-ir" }, 226 { .compatible = "amlogic,meson-gxbb-ir" }, 227 { }, 228 }; 229 MODULE_DEVICE_TABLE(of, meson_ir_match); 230 231 static struct platform_driver meson_ir_driver = { 232 .probe = meson_ir_probe, 233 .remove = meson_ir_remove, 234 .shutdown = meson_ir_shutdown, 235 .driver = { 236 .name = DRIVER_NAME, 237 .of_match_table = meson_ir_match, 238 }, 239 }; 240 241 module_platform_driver(meson_ir_driver); 242 243 MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver"); 244 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); 245 MODULE_LICENSE("GPL v2"); 246