LXR linux/drivers/media/rc/sunxi-cir.c

   1/*
   2 * Driver for Allwinner sunXi IR controller
   3 *
   4 * Copyright (C) 2014 Alexsey Shestacov <wingrime@linux-sunxi.org>
   5 * Copyright (C) 2014 Alexander Bersenev <bay@hackerdom.ru>
   6 *
   7 * Based on sun5i-ir.c:
   8 * Copyright (C) 2007-2012 Daniel Wang
   9 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
  10 *
  11 * This program is free software; you can redistribute it and/or
  12 * modify it under the terms of the GNU General Public License as
  13 * published by the Free Software Foundation; either version 2 of
  14 * the License, or (at your option) any later version.
  15 *
  16 * This program is distributed in the hope that it will be useful,
  17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  19 * GNU General Public License for more details.
  20 */
  21
  22#include <linux/clk.h>
  23#include <linux/interrupt.h>
  24#include <linux/module.h>
  25#include <linux/of_platform.h>
  26#include <linux/reset.h>
  27#include <media/rc-core.h>
  28
  29#define SUNXI_IR_DEV "sunxi-ir"
  30
  31/* Registers */
  32/* IR Control */
  33#define SUNXI_IR_CTL_REG      0x00
  34/* Global Enable */
  35#define REG_CTL_GEN                     BIT(0)
  36/* RX block enable */
  37#define REG_CTL_RXEN                    BIT(1)
  38/* CIR mode */
  39#define REG_CTL_MD                      (BIT(4) | BIT(5))
  40
  41/* Rx Config */
  42#define SUNXI_IR_RXCTL_REG    0x10
  43/* Pulse Polarity Invert flag */
  44#define REG_RXCTL_RPPI                  BIT(2)
  45
  46/* Rx Data */
  47#define SUNXI_IR_RXFIFO_REG   0x20
  48
  49/* Rx Interrupt Enable */
  50#define SUNXI_IR_RXINT_REG    0x2C
  51/* Rx FIFO Overflow */
  52#define REG_RXINT_ROI_EN                BIT(0)
  53/* Rx Packet End */
  54#define REG_RXINT_RPEI_EN               BIT(1)
  55/* Rx FIFO Data Available */
  56#define REG_RXINT_RAI_EN                BIT(4)
  57
  58/* Rx FIFO available byte level */
  59#define REG_RXINT_RAL(val)    ((val) << 8)
  60
  61/* Rx Interrupt Status */
  62#define SUNXI_IR_RXSTA_REG    0x30
  63/* RX FIFO Get Available Counter */
  64#define REG_RXSTA_GET_AC(val) (((val) >> 8) & (ir->fifo_size * 2 - 1))
  65/* Clear all interrupt status value */
  66#define REG_RXSTA_CLEARALL    0xff
  67
  68/* IR Sample Config */
  69#define SUNXI_IR_CIR_REG      0x34
  70/* CIR_REG register noise threshold */
  71#define REG_CIR_NTHR(val)    (((val) << 2) & (GENMASK(7, 2)))
  72/* CIR_REG register idle threshold */
  73#define REG_CIR_ITHR(val)    (((val) << 8) & (GENMASK(15, 8)))
  74
  75/* Required frequency for IR0 or IR1 clock in CIR mode */
  76#define SUNXI_IR_BASE_CLK     8000000
  77/* Frequency after IR internal divider  */
  78#define SUNXI_IR_CLK          (SUNXI_IR_BASE_CLK / 64)
  79/* Sample period in ns */
  80#define SUNXI_IR_SAMPLE       (1000000000ul / SUNXI_IR_CLK)
  81/* Noise threshold in samples  */
  82#define SUNXI_IR_RXNOISE      1
  83/* Idle Threshold in samples */
  84#define SUNXI_IR_RXIDLE       20
  85/* Time after which device stops sending data in ms */
  86#define SUNXI_IR_TIMEOUT      120
  87
  88struct sunxi_ir {
  89        spinlock_t      ir_lock;
  90        struct rc_dev   *rc;
  91        void __iomem    *base;
  92        int             irq;
  93        int             fifo_size;
  94        struct clk      *clk;
  95        struct clk      *apb_clk;
  96        struct reset_control *rst;
  97        const char      *map_name;
  98};
  99
 100static irqreturn_t sunxi_ir_irq(int irqno, void *dev_id)
 101{
 102        unsigned long status;
 103        unsigned char dt;
 104        unsigned int cnt, rc;
 105        struct sunxi_ir *ir = dev_id;
 106        DEFINE_IR_RAW_EVENT(rawir);
 107
 108        spin_lock(&ir->ir_lock);
 109
 110        status = readl(ir->base + SUNXI_IR_RXSTA_REG);
 111
 112        /* clean all pending statuses */
 113        writel(status | REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
 114
 115        if (status & (REG_RXINT_RAI_EN | REG_RXINT_RPEI_EN)) {
 116                /* How many messages in fifo */
 117                rc  = REG_RXSTA_GET_AC(status);
 118                /* Sanity check */
 119                rc = rc > ir->fifo_size ? ir->fifo_size : rc;
 120                /* If we have data */
 121                for (cnt = 0; cnt < rc; cnt++) {
 122                        /* for each bit in fifo */
 123                        dt = readb(ir->base + SUNXI_IR_RXFIFO_REG);
 124                        rawir.pulse = (dt & 0x80) != 0;
 125                        rawir.duration = ((dt & 0x7f) + 1) * SUNXI_IR_SAMPLE;
 126                        ir_raw_event_store_with_filter(ir->rc, &rawir);
 127                }
 128        }
 129
 130        if (status & REG_RXINT_ROI_EN) {
 131                ir_raw_event_reset(ir->rc);
 132        } else if (status & REG_RXINT_RPEI_EN) {
 133                ir_raw_event_set_idle(ir->rc, true);
 134                ir_raw_event_handle(ir->rc);
 135        }
 136
 137        spin_unlock(&ir->ir_lock);
 138
 139        return IRQ_HANDLED;
 140}
 141
 142static int sunxi_ir_probe(struct platform_device *pdev)
 143{
 144        int ret = 0;
 145        unsigned long tmp = 0;
 146
 147        struct device *dev = &pdev->dev;
 148        struct device_node *dn = dev->of_node;
 149        struct resource *res;
 150        struct sunxi_ir *ir;
 151
 152        ir = devm_kzalloc(dev, sizeof(struct sunxi_ir), GFP_KERNEL);
 153        if (!ir)
 154                return -ENOMEM;
 155
 156        spin_lock_init(&ir->ir_lock);
 157
 158        if (of_device_is_compatible(dn, "allwinner,sun5i-a13-ir"))
 159                ir->fifo_size = 64;
 160        else
 161                ir->fifo_size = 16;
 162
 163        /* Clock */
 164        ir->apb_clk = devm_clk_get(dev, "apb");
 165        if (IS_ERR(ir->apb_clk)) {
 166                dev_err(dev, "failed to get a apb clock.\n");
 167                return PTR_ERR(ir->apb_clk);
 168        }
 169        ir->clk = devm_clk_get(dev, "ir");
 170        if (IS_ERR(ir->clk)) {
 171                dev_err(dev, "failed to get a ir clock.\n");
 172                return PTR_ERR(ir->clk);
 173        }
 174
 175        /* Reset (optional) */
 176        ir->rst = devm_reset_control_get_optional(dev, NULL);
 177        if (IS_ERR(ir->rst)) {
 178                ret = PTR_ERR(ir->rst);
 179                if (ret == -EPROBE_DEFER)
 180                        return ret;
 181                ir->rst = NULL;
 182        } else {
 183                ret = reset_control_deassert(ir->rst);
 184                if (ret)
 185                        return ret;
 186        }
 187
 188        ret = clk_set_rate(ir->clk, SUNXI_IR_BASE_CLK);
 189        if (ret) {
 190                dev_err(dev, "set ir base clock failed!\n");
 191                goto exit_reset_assert;
 192        }
 193
 194        if (clk_prepare_enable(ir->apb_clk)) {
 195                dev_err(dev, "try to enable apb_ir_clk failed\n");
 196                ret = -EINVAL;
 197                goto exit_reset_assert;
 198        }
 199
 200        if (clk_prepare_enable(ir->clk)) {
 201                dev_err(dev, "try to enable ir_clk failed\n");
 202                ret = -EINVAL;
 203                goto exit_clkdisable_apb_clk;
 204        }
 205
 206        /* IO */
 207        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 208        ir->base = devm_ioremap_resource(dev, res);
 209        if (IS_ERR(ir->base)) {
 210                dev_err(dev, "failed to map registers\n");
 211                ret = PTR_ERR(ir->base);
 212                goto exit_clkdisable_clk;
 213        }
 214
 215        ir->rc = rc_allocate_device(RC_DRIVER_IR_RAW);
 216        if (!ir->rc) {
 217                dev_err(dev, "failed to allocate device\n");
 218                ret = -ENOMEM;
 219                goto exit_clkdisable_clk;
 220        }
 221
 222        ir->rc->priv = ir;
 223        ir->rc->input_name = SUNXI_IR_DEV;
 224        ir->rc->input_phys = "sunxi-ir/input0";
 225        ir->rc->input_id.bustype = BUS_HOST;
 226        ir->rc->input_id.vendor = 0x0001;
 227        ir->rc->input_id.product = 0x0001;
 228        ir->rc->input_id.version = 0x0100;
 229        ir->map_name = of_get_property(dn, "linux,rc-map-name", NULL);
 230        ir->rc->map_name = ir->map_name ?: RC_MAP_EMPTY;
 231        ir->rc->dev.parent = dev;
 232        ir->rc->allowed_protocols = RC_BIT_ALL_IR_DECODER;
 233        ir->rc->rx_resolution = SUNXI_IR_SAMPLE;
 234        ir->rc->timeout = MS_TO_NS(SUNXI_IR_TIMEOUT);
 235        ir->rc->driver_name = SUNXI_IR_DEV;
 236
 237        ret = rc_register_device(ir->rc);
 238        if (ret) {
 239                dev_err(dev, "failed to register rc device\n");
 240                goto exit_free_dev;
 241        }
 242
 243        platform_set_drvdata(pdev, ir);
 244
 245        /* IRQ */
 246        ir->irq = platform_get_irq(pdev, 0);
 247        if (ir->irq < 0) {
 248                dev_err(dev, "no irq resource\n");
 249                ret = ir->irq;
 250                goto exit_free_dev;
 251        }
 252
 253        ret = devm_request_irq(dev, ir->irq, sunxi_ir_irq, 0, SUNXI_IR_DEV, ir);
 254        if (ret) {
 255                dev_err(dev, "failed request irq\n");
 256                goto exit_free_dev;
 257        }
 258
 259        /* Enable CIR Mode */
 260        writel(REG_CTL_MD, ir->base+SUNXI_IR_CTL_REG);
 261
 262        /* Set noise threshold and idle threshold */
 263        writel(REG_CIR_NTHR(SUNXI_IR_RXNOISE)|REG_CIR_ITHR(SUNXI_IR_RXIDLE),
 264               ir->base + SUNXI_IR_CIR_REG);
 265
 266        /* Invert Input Signal */
 267        writel(REG_RXCTL_RPPI, ir->base + SUNXI_IR_RXCTL_REG);
 268
 269        /* Clear All Rx Interrupt Status */
 270        writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
 271
 272        /*
 273         * Enable IRQ on overflow, packet end, FIFO available with trigger
 274         * level
 275         */
 276        writel(REG_RXINT_ROI_EN | REG_RXINT_RPEI_EN |
 277               REG_RXINT_RAI_EN | REG_RXINT_RAL(ir->fifo_size / 2 - 1),
 278               ir->base + SUNXI_IR_RXINT_REG);
 279
 280        /* Enable IR Module */
 281        tmp = readl(ir->base + SUNXI_IR_CTL_REG);
 282        writel(tmp | REG_CTL_GEN | REG_CTL_RXEN, ir->base + SUNXI_IR_CTL_REG);
 283
 284        dev_info(dev, "initialized sunXi IR driver\n");
 285        return 0;
 286
 287exit_free_dev:
 288        rc_free_device(ir->rc);
 289exit_clkdisable_clk:
 290        clk_disable_unprepare(ir->clk);
 291exit_clkdisable_apb_clk:
 292        clk_disable_unprepare(ir->apb_clk);
 293exit_reset_assert:
 294        if (ir->rst)
 295                reset_control_assert(ir->rst);
 296
 297        return ret;
 298}
 299
 300static int sunxi_ir_remove(struct platform_device *pdev)
 301{
 302        unsigned long flags;
 303        struct sunxi_ir *ir = platform_get_drvdata(pdev);
 304
 305        clk_disable_unprepare(ir->clk);
 306        clk_disable_unprepare(ir->apb_clk);
 307        if (ir->rst)
 308                reset_control_assert(ir->rst);
 309
 310        spin_lock_irqsave(&ir->ir_lock, flags);
 311        /* disable IR IRQ */
 312        writel(0, ir->base + SUNXI_IR_RXINT_REG);
 313        /* clear All Rx Interrupt Status */
 314        writel(REG_RXSTA_CLEARALL, ir->base + SUNXI_IR_RXSTA_REG);
 315        /* disable IR */
 316        writel(0, ir->base + SUNXI_IR_CTL_REG);
 317        spin_unlock_irqrestore(&ir->ir_lock, flags);
 318
 319        rc_unregister_device(ir->rc);
 320        return 0;
 321}
 322
 323static const struct of_device_id sunxi_ir_match[] = {
 324        { .compatible = "allwinner,sun4i-a10-ir", },
 325        { .compatible = "allwinner,sun5i-a13-ir", },
 326        {},
 327};
 328MODULE_DEVICE_TABLE(of, sunxi_ir_match);
 329
 330static struct platform_driver sunxi_ir_driver = {
 331        .probe          = sunxi_ir_probe,
 332        .remove         = sunxi_ir_remove,
 333        .driver = {
 334                .name = SUNXI_IR_DEV,
 335                .of_match_table = sunxi_ir_match,
 336        },
 337};
 338
 339module_platform_driver(sunxi_ir_driver);
 340
 341MODULE_DESCRIPTION("Allwinner sunXi IR controller driver");
 342MODULE_AUTHOR("Alexsey Shestacov <wingrime@linux-sunxi.org>");
 343MODULE_LICENSE("GPL");
 344