drivers/media/rc/meson-ir.c

   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 = 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                 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
 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
 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");