drivers/media/rc/img-ir/img-ir-core.c

   1 /*
   2  * ImgTec IR Decoder found in PowerDown Controller.
   3  *
   4  * Copyright 2010-2014 Imagination Technologies Ltd.
   5  *
   6  * This contains core img-ir code for setting up the driver. The two interfaces
   7  * (raw and hardware decode) are handled separately.
   8  */
   9
  10 #include <linux/clk.h>
  11 #include <linux/init.h>
  12 #include <linux/interrupt.h>
  13 #include <linux/io.h>
  14 #include <linux/module.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/slab.h>
  17 #include <linux/spinlock.h>
  18 #include "img-ir.h"
  19
  20 static irqreturn_t img_ir_isr(int irq, void *dev_id)
  21 {
  22         struct img_ir_priv *priv = dev_id;
  23         u32 irq_status;
  24
  25         spin_lock(&priv->lock);
  26         /* we have to clear irqs before reading */
  27         irq_status = img_ir_read(priv, IMG_IR_IRQ_STATUS);
  28         img_ir_write(priv, IMG_IR_IRQ_CLEAR, irq_status);
  29
  30         /* don't handle valid data irqs if we're only interested in matches */
  31         irq_status &= img_ir_read(priv, IMG_IR_IRQ_ENABLE);
  32
  33         /* hand off edge interrupts to raw decode handler */
  34         if (irq_status & IMG_IR_IRQ_EDGE && img_ir_raw_enabled(&priv->raw))
  35                 img_ir_isr_raw(priv, irq_status);
  36
  37         /* hand off hardware match interrupts to hardware decode handler */
  38         if (irq_status & (IMG_IR_IRQ_DATA_MATCH |
  39                           IMG_IR_IRQ_DATA_VALID |
  40                           IMG_IR_IRQ_DATA2_VALID) &&
  41             img_ir_hw_enabled(&priv->hw))
  42                 img_ir_isr_hw(priv, irq_status);
  43
  44         spin_unlock(&priv->lock);
  45         return IRQ_HANDLED;
  46 }
  47
  48 static void img_ir_setup(struct img_ir_priv *priv)
  49 {
  50         /* start off with interrupts disabled */
  51         img_ir_write(priv, IMG_IR_IRQ_ENABLE, 0);
  52
  53         img_ir_setup_raw(priv);
  54         img_ir_setup_hw(priv);
  55
  56         if (!IS_ERR(priv->clk))
  57                 clk_prepare_enable(priv->clk);
  58 }
  59
  60 static void img_ir_ident(struct img_ir_priv *priv)
  61 {
  62         u32 core_rev = img_ir_read(priv, IMG_IR_CORE_REV);
  63
  64         dev_info(priv->dev,
  65                  "IMG IR Decoder (%d.%d.%d.%d) probed successfully\n",
  66                  (core_rev & IMG_IR_DESIGNER) >> IMG_IR_DESIGNER_SHIFT,
  67                  (core_rev & IMG_IR_MAJOR_REV) >> IMG_IR_MAJOR_REV_SHIFT,
  68                  (core_rev & IMG_IR_MINOR_REV) >> IMG_IR_MINOR_REV_SHIFT,
  69                  (core_rev & IMG_IR_MAINT_REV) >> IMG_IR_MAINT_REV_SHIFT);
  70         dev_info(priv->dev, "Modes:%s%s\n",
  71                  img_ir_hw_enabled(&priv->hw) ? " hardware" : "",
  72                  img_ir_raw_enabled(&priv->raw) ? " raw" : "");
  73 }
  74
  75 static int img_ir_probe(struct platform_device *pdev)
  76 {
  77         struct img_ir_priv *priv;
  78         struct resource *res_regs;
  79         int irq, error, error2;
  80
  81         /* Get resources from platform device */
  82         irq = platform_get_irq(pdev, 0);
  83         if (irq < 0) {
  84                 dev_err(&pdev->dev, "cannot find IRQ resource\n");
  85                 return irq;
  86         }
  87
  88         /* Private driver data */
  89         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  90         if (!priv) {
  91                 dev_err(&pdev->dev, "cannot allocate device data\n");
  92                 return -ENOMEM;
  93         }
  94         platform_set_drvdata(pdev, priv);
  95         priv->dev = &pdev->dev;
  96         spin_lock_init(&priv->lock);
  97
  98         /* Ioremap the registers */
  99         res_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 100         priv->reg_base = devm_ioremap_resource(&pdev->dev, res_regs);
 101         if (IS_ERR(priv->reg_base))
 102                 return PTR_ERR(priv->reg_base);
 103
 104         /* Get core clock */
 105         priv->clk = devm_clk_get(&pdev->dev, "core");
 106         if (IS_ERR(priv->clk))
 107                 dev_warn(&pdev->dev, "cannot get core clock resource\n");
 108         /*
 109          * The driver doesn't need to know about the system ("sys") or power
 110          * modulation ("mod") clocks yet
 111          */
 112
 113         /* Set up raw & hw decoder */
 114         error = img_ir_probe_raw(priv);
 115         error2 = img_ir_probe_hw(priv);
 116         if (error && error2)
 117                 return (error == -ENODEV) ? error2 : error;
 118
 119         /* Get the IRQ */
 120         priv->irq = irq;
 121         error = request_irq(priv->irq, img_ir_isr, 0, "img-ir", priv);
 122         if (error) {
 123                 dev_err(&pdev->dev, "cannot register IRQ %u\n",
 124                         priv->irq);
 125                 error = -EIO;
 126                 goto err_irq;
 127         }
 128
 129         img_ir_ident(priv);
 130         img_ir_setup(priv);
 131
 132         return 0;
 133
 134 err_irq:
 135         img_ir_remove_hw(priv);
 136         img_ir_remove_raw(priv);
 137         return error;
 138 }
 139
 140 static int img_ir_remove(struct platform_device *pdev)
 141 {
 142         struct img_ir_priv *priv = platform_get_drvdata(pdev);
 143
 144         free_irq(priv->irq, img_ir_isr);
 145         img_ir_remove_hw(priv);
 146         img_ir_remove_raw(priv);
 147
 148         if (!IS_ERR(priv->clk))
 149                 clk_disable_unprepare(priv->clk);
 150         return 0;
 151 }
 152
 153 static SIMPLE_DEV_PM_OPS(img_ir_pmops, img_ir_suspend, img_ir_resume);
 154
 155 static const struct of_device_id img_ir_match[] = {
 156         { .compatible = "img,ir-rev1" },
 157         {}
 158 };
 159 MODULE_DEVICE_TABLE(of, img_ir_match);
 160
 161 static struct platform_driver img_ir_driver = {
 162         .driver = {
 163                 .name = "img-ir",
 164                 .owner  = THIS_MODULE,
 165                 .of_match_table = img_ir_match,
 166                 .pm = &img_ir_pmops,
 167         },
 168         .probe = img_ir_probe,
 169         .remove = img_ir_remove,
 170 };
 171
 172 module_platform_driver(img_ir_driver);
 173
 174 MODULE_AUTHOR("Imagination Technologies Ltd.");
 175 MODULE_DESCRIPTION("ImgTec IR");
 176 MODULE_LICENSE("GPL");