1 /* 2 * Driver for Amlogic Meson IR remote receiver 3 * 4 * Copyright (C) 2014 Beniamino Galvani <b.galvani@gmail.com> 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * version 2 as published by the Free Software Foundation. 9 * 10 * You should have received a copy of the GNU General Public License 11 * along with this program. If not, see <http://www.gnu.org/licenses/>. 12 */ 13 14 #include <linux/device.h> 15 #include <linux/err.h> 16 #include <linux/interrupt.h> 17 #include <linux/io.h> 18 #include <linux/module.h> 19 #include <linux/of_platform.h> 20 #include <linux/platform_device.h> 21 #include <linux/spinlock.h> 22 #include <linux/bitfield.h> 23 24 #include <media/rc-core.h> 25 26 #define DRIVER_NAME "meson-ir" 27 28 /* valid on all Meson platforms */ 29 #define IR_DEC_LDR_ACTIVE 0x00 30 #define IR_DEC_LDR_IDLE 0x04 31 #define IR_DEC_LDR_REPEAT 0x08 32 #define IR_DEC_BIT_0 0x0c 33 #define IR_DEC_REG0 0x10 34 #define IR_DEC_FRAME 0x14 35 #define IR_DEC_STATUS 0x18 36 #define IR_DEC_REG1 0x1c 37 /* only available on Meson 8b and newer */ 38 #define IR_DEC_REG2 0x20 39 40 #define REG0_RATE_MASK GENMASK(11, 0) 41 42 #define DECODE_MODE_NEC 0x0 43 #define DECODE_MODE_RAW 0x2 44 45 /* Meson 6b uses REG1 to configure the mode */ 46 #define REG1_MODE_MASK GENMASK(8, 7) 47 #define REG1_MODE_SHIFT 7 48 49 /* Meson 8b / GXBB use REG2 to configure the mode */ 50 #define REG2_MODE_MASK GENMASK(3, 0) 51 #define REG2_MODE_SHIFT 0 52 53 #define REG1_TIME_IV_MASK GENMASK(28, 16) 54 55 #define REG1_IRQSEL_MASK GENMASK(3, 2) 56 #define REG1_IRQSEL_NEC_MODE 0 57 #define REG1_IRQSEL_RISE_FALL 1 58 #define REG1_IRQSEL_FALL 2 59 #define REG1_IRQSEL_RISE 3 60 61 #define REG1_RESET BIT(0) 62 #define REG1_ENABLE BIT(15) 63 64 #define STATUS_IR_DEC_IN BIT(8) 65 66 #define MESON_TRATE 10 /* us */ 67 68 struct meson_ir { 69 void __iomem *reg; 70 struct rc_dev *rc; 71 spinlock_t lock; 72 }; 73 74 static void meson_ir_set_mask(struct meson_ir *ir, unsigned int reg, 75 u32 mask, u32 value) 76 { 77 u32 data; 78 79 data = readl(ir->reg + reg); 80 data &= ~mask; 81 data |= (value & mask); 82 writel(data, ir->reg + reg); 83 } 84 85 static irqreturn_t meson_ir_irq(int irqno, void *dev_id) 86 { 87 struct meson_ir *ir = dev_id; 88 u32 duration, status; 89 DEFINE_IR_RAW_EVENT(rawir); 90 91 spin_lock(&ir->lock); 92 93 duration = readl_relaxed(ir->reg + IR_DEC_REG1); 94 duration = FIELD_GET(REG1_TIME_IV_MASK, duration); 95 rawir.duration = US_TO_NS(duration * MESON_TRATE); 96 97 status = readl_relaxed(ir->reg + IR_DEC_STATUS); 98 rawir.pulse = !!(status & STATUS_IR_DEC_IN); 99 100 ir_raw_event_store(ir->rc, &rawir); 101 ir_raw_event_handle(ir->rc); 102 103 spin_unlock(&ir->lock); 104 105 return IRQ_HANDLED; 106 } 107 108 static int meson_ir_probe(struct platform_device *pdev) 109 { 110 struct device *dev = &pdev->dev; 111 struct device_node *node = dev->of_node; 112 struct resource *res; 113 const char *map_name; 114 struct meson_ir *ir; 115 int irq, ret; 116 117 ir = devm_kzalloc(dev, sizeof(struct meson_ir), GFP_KERNEL); 118 if (!ir) 119 return -ENOMEM; 120 121 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 122 ir->reg = devm_ioremap_resource(dev, res); 123 if (IS_ERR(ir->reg)) { 124 dev_err(dev, "failed to map registers\n"); 125 return PTR_ERR(ir->reg); 126 } 127 128 irq = platform_get_irq(pdev, 0); 129 if (irq < 0) { 130 dev_err(dev, "no irq resource\n"); 131 return irq; 132 } 133 134 ir->rc = devm_rc_allocate_device(dev, RC_DRIVER_IR_RAW); 135 if (!ir->rc) { 136 dev_err(dev, "failed to allocate rc device\n"); 137 return -ENOMEM; 138 } 139 140 ir->rc->priv = ir; 141 ir->rc->input_name = DRIVER_NAME; 142 ir->rc->input_phys = DRIVER_NAME "/input0"; 143 ir->rc->input_id.bustype = BUS_HOST; 144 map_name = of_get_property(node, "linux,rc-map-name", NULL); 145 ir->rc->map_name = map_name ? map_name : RC_MAP_EMPTY; 146 ir->rc->allowed_protocols = RC_BIT_ALL_IR_DECODER; 147 ir->rc->rx_resolution = US_TO_NS(MESON_TRATE); 148 ir->rc->timeout = MS_TO_NS(200); 149 ir->rc->driver_name = DRIVER_NAME; 150 151 spin_lock_init(&ir->lock); 152 platform_set_drvdata(pdev, ir); 153 154 ret = devm_rc_register_device(dev, ir->rc); 155 if (ret) { 156 dev_err(dev, "failed to register rc device\n"); 157 return ret; 158 } 159 160 ret = devm_request_irq(dev, irq, meson_ir_irq, 0, NULL, ir); 161 if (ret) { 162 dev_err(dev, "failed to request irq\n"); 163 return ret; 164 } 165 166 /* Reset the decoder */ 167 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, REG1_RESET); 168 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, 0); 169 170 /* Set general operation mode (= raw/software decoding) */ 171 if (of_device_is_compatible(node, "amlogic,meson6-ir")) 172 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK, 173 FIELD_PREP(REG1_MODE_MASK, DECODE_MODE_RAW)); 174 else 175 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK, 176 FIELD_PREP(REG2_MODE_MASK, DECODE_MODE_RAW)); 177 178 /* Set rate */ 179 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, MESON_TRATE - 1); 180 /* IRQ on rising and falling edges */ 181 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_IRQSEL_MASK, 182 FIELD_PREP(REG1_IRQSEL_MASK, REG1_IRQSEL_RISE_FALL)); 183 /* Enable the decoder */ 184 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, REG1_ENABLE); 185 186 dev_info(dev, "receiver initialized\n"); 187 188 return 0; 189 } 190 191 static int meson_ir_remove(struct platform_device *pdev) 192 { 193 struct meson_ir *ir = platform_get_drvdata(pdev); 194 unsigned long flags; 195 196 /* Disable the decoder */ 197 spin_lock_irqsave(&ir->lock, flags); 198 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, 0); 199 spin_unlock_irqrestore(&ir->lock, flags); 200 201 return 0; 202 } 203 204 static void meson_ir_shutdown(struct platform_device *pdev) 205 { 206 struct device *dev = &pdev->dev; 207 struct device_node *node = dev->of_node; 208 struct meson_ir *ir = platform_get_drvdata(pdev); 209 unsigned long flags; 210 211 spin_lock_irqsave(&ir->lock, flags); 212 213 /* 214 * Set operation mode to NEC/hardware decoding to give 215 * bootloader a chance to power the system back on 216 */ 217 if (of_device_is_compatible(node, "amlogic,meson6-ir")) 218 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK, 219 DECODE_MODE_NEC << REG1_MODE_SHIFT); 220 else 221 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK, 222 DECODE_MODE_NEC << REG2_MODE_SHIFT); 223 224 /* Set rate to default value */ 225 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, 0x13); 226 227 spin_unlock_irqrestore(&ir->lock, flags); 228 } 229 230 static const struct of_device_id meson_ir_match[] = { 231 { .compatible = "amlogic,meson6-ir" }, 232 { .compatible = "amlogic,meson8b-ir" }, 233 { .compatible = "amlogic,meson-gxbb-ir" }, 234 { }, 235 }; 236 MODULE_DEVICE_TABLE(of, meson_ir_match); 237 238 static struct platform_driver meson_ir_driver = { 239 .probe = meson_ir_probe, 240 .remove = meson_ir_remove, 241 .shutdown = meson_ir_shutdown, 242 .driver = { 243 .name = DRIVER_NAME, 244 .of_match_table = meson_ir_match, 245 }, 246 }; 247 248 module_platform_driver(meson_ir_driver); 249 250 MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver"); 251 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); 252 MODULE_LICENSE("GPL v2"); 253