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 23 #include <media/rc-core.h> 24 25 #define DRIVER_NAME "meson-ir" 26 27 /* valid on all Meson platforms */ 28 #define IR_DEC_LDR_ACTIVE 0x00 29 #define IR_DEC_LDR_IDLE 0x04 30 #define IR_DEC_LDR_REPEAT 0x08 31 #define IR_DEC_BIT_0 0x0c 32 #define IR_DEC_REG0 0x10 33 #define IR_DEC_FRAME 0x14 34 #define IR_DEC_STATUS 0x18 35 #define IR_DEC_REG1 0x1c 36 /* only available on Meson 8b and newer */ 37 #define IR_DEC_REG2 0x20 38 39 #define REG0_RATE_MASK (BIT(11) - 1) 40 41 #define DECODE_MODE_NEC 0x0 42 #define DECODE_MODE_RAW 0x2 43 44 /* Meson 6b uses REG1 to configure the mode */ 45 #define REG1_MODE_MASK GENMASK(8, 7) 46 #define REG1_MODE_SHIFT 7 47 48 /* Meson 8b / GXBB use REG2 to configure the mode */ 49 #define REG2_MODE_MASK GENMASK(3, 0) 50 #define REG2_MODE_SHIFT 0 51 52 #define REG1_TIME_IV_SHIFT 16 53 #define REG1_TIME_IV_MASK ((BIT(13) - 1) << REG1_TIME_IV_SHIFT) 54 55 #define REG1_IRQSEL_MASK (BIT(2) | BIT(3)) 56 #define REG1_IRQSEL_NEC_MODE (0 << 2) 57 #define REG1_IRQSEL_RISE_FALL (1 << 2) 58 #define REG1_IRQSEL_FALL (2 << 2) 59 #define REG1_IRQSEL_RISE (3 << 2) 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 int irq; 72 spinlock_t lock; 73 }; 74 75 static void meson_ir_set_mask(struct meson_ir *ir, unsigned int reg, 76 u32 mask, u32 value) 77 { 78 u32 data; 79 80 data = readl(ir->reg + reg); 81 data &= ~mask; 82 data |= (value & mask); 83 writel(data, ir->reg + reg); 84 } 85 86 static irqreturn_t meson_ir_irq(int irqno, void *dev_id) 87 { 88 struct meson_ir *ir = dev_id; 89 u32 duration; 90 DEFINE_IR_RAW_EVENT(rawir); 91 92 spin_lock(&ir->lock); 93 94 duration = readl(ir->reg + IR_DEC_REG1); 95 duration = (duration & REG1_TIME_IV_MASK) >> REG1_TIME_IV_SHIFT; 96 rawir.duration = US_TO_NS(duration * MESON_TRATE); 97 98 rawir.pulse = !!(readl(ir->reg + IR_DEC_STATUS) & STATUS_IR_DEC_IN); 99 100 ir_raw_event_store_with_filter(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 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 ir->irq = platform_get_irq(pdev, 0); 129 if (ir->irq < 0) { 130 dev_err(dev, "no irq resource\n"); 131 return ir->irq; 132 } 133 134 ir->rc = rc_allocate_device(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->dev.parent = dev; 147 ir->rc->allowed_protocols = RC_BIT_ALL_IR_DECODER; 148 ir->rc->rx_resolution = US_TO_NS(MESON_TRATE); 149 ir->rc->timeout = MS_TO_NS(200); 150 ir->rc->driver_name = DRIVER_NAME; 151 152 spin_lock_init(&ir->lock); 153 platform_set_drvdata(pdev, ir); 154 155 ret = rc_register_device(ir->rc); 156 if (ret) { 157 dev_err(dev, "failed to register rc device\n"); 158 goto out_free; 159 } 160 161 ret = devm_request_irq(dev, ir->irq, meson_ir_irq, 0, "ir-meson", ir); 162 if (ret) { 163 dev_err(dev, "failed to request irq\n"); 164 goto out_unreg; 165 } 166 167 /* Reset the decoder */ 168 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, REG1_RESET); 169 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_RESET, 0); 170 171 /* Set general operation mode (= raw/software decoding) */ 172 if (of_device_is_compatible(node, "amlogic,meson6-ir")) 173 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_MODE_MASK, 174 DECODE_MODE_RAW << REG1_MODE_SHIFT); 175 else 176 meson_ir_set_mask(ir, IR_DEC_REG2, REG2_MODE_MASK, 177 DECODE_MODE_RAW << REG2_MODE_SHIFT); 178 179 /* Set rate */ 180 meson_ir_set_mask(ir, IR_DEC_REG0, REG0_RATE_MASK, MESON_TRATE - 1); 181 /* IRQ on rising and falling edges */ 182 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_IRQSEL_MASK, 183 REG1_IRQSEL_RISE_FALL); 184 /* Enable the decoder */ 185 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, REG1_ENABLE); 186 187 dev_info(dev, "receiver initialized\n"); 188 189 return 0; 190 out_unreg: 191 rc_unregister_device(ir->rc); 192 ir->rc = NULL; 193 out_free: 194 rc_free_device(ir->rc); 195 196 return ret; 197 } 198 199 static int meson_ir_remove(struct platform_device *pdev) 200 { 201 struct meson_ir *ir = platform_get_drvdata(pdev); 202 unsigned long flags; 203 204 /* Disable the decoder */ 205 spin_lock_irqsave(&ir->lock, flags); 206 meson_ir_set_mask(ir, IR_DEC_REG1, REG1_ENABLE, 0); 207 spin_unlock_irqrestore(&ir->lock, flags); 208 209 rc_unregister_device(ir->rc); 210 211 return 0; 212 } 213 214 static const struct of_device_id meson_ir_match[] = { 215 { .compatible = "amlogic,meson6-ir" }, 216 { .compatible = "amlogic,meson8b-ir" }, 217 { .compatible = "amlogic,meson-gxbb-ir" }, 218 { }, 219 }; 220 MODULE_DEVICE_TABLE(of, meson_ir_match); 221 222 static struct platform_driver meson_ir_driver = { 223 .probe = meson_ir_probe, 224 .remove = meson_ir_remove, 225 .driver = { 226 .name = DRIVER_NAME, 227 .of_match_table = meson_ir_match, 228 }, 229 }; 230 231 module_platform_driver(meson_ir_driver); 232 233 MODULE_DESCRIPTION("Amlogic Meson IR remote receiver driver"); 234 MODULE_AUTHOR("Beniamino Galvani <b.galvani@gmail.com>"); 235 MODULE_LICENSE("GPL v2"); 236