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

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * ImgTec IR Decoder found in PowerDown Controller.
   4  *
   5  * Copyright 2010-2014 Imagination Technologies Ltd.
   6  *
   7  * This contains core img-ir code for setting up the driver. The two interfaces
   8  * (raw and hardware decode) are handled separately.
   9  */
  10
  11 #include <linux/clk.h>
  12 #include <linux/init.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/io.h>
  15 #include <linux/module.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/slab.h>
  18 #include <linux/spinlock.h>
  19 #include "img-ir.h"
  20
  21 static irqreturn_t img_ir_isr(int irq, void *dev_id)
  22 {
  23         struct img_ir_priv *priv = dev_id;
  24         u32 irq_status;
  25
  26         spin_lock(&priv->lock);
  27         /* we have to clear irqs before reading */
  28         irq_status = img_ir_read(priv, IMG_IR_IRQ_STATUS);
  29         img_ir_write(priv, IMG_IR_IRQ_CLEAR, irq_status);
  30
  31         /* don't handle valid data irqs if we're only interested in matches */
  32         irq_status &= img_ir_read(priv, IMG_IR_IRQ_ENABLE);
  33
  34         /* hand off edge interrupts to raw decode handler */
  35         if (irq_status & IMG_IR_IRQ_EDGE && img_ir_raw_enabled(&priv->raw))
  36                 img_ir_isr_raw(priv, irq_status);
  37
  38         /* hand off hardware match interrupts to hardware decode handler */
  39         if (irq_status & (IMG_IR_IRQ_DATA_MATCH |
  40                           IMG_IR_IRQ_DATA_VALID |
  41                           IMG_IR_IRQ_DATA2_VALID) &&
  42             img_ir_hw_enabled(&priv->hw))
  43                 img_ir_isr_hw(priv, irq_status);
  44
  45         spin_unlock(&priv->lock);
  46         return IRQ_HANDLED;
  47 }
  48
  49 static void img_ir_setup(struct img_ir_priv *priv)
  50 {
  51         /* start off with interrupts disabled */
  52         img_ir_write(priv, IMG_IR_IRQ_ENABLE, 0);
  53
  54         img_ir_setup_raw(priv);
  55         img_ir_setup_hw(priv);
  56
  57         if (!IS_ERR(priv->clk))
  58                 clk_prepare_enable(priv->clk);
  59 }
  60
  61 static void img_ir_ident(struct img_ir_priv *priv)
  62 {
  63         u32 core_rev = img_ir_read(priv, IMG_IR_CORE_REV);
  64
  65         dev_info(priv->dev,
  66                  "IMG IR Decoder (%d.%d.%d.%d) probed successfully\n",
  67                  (core_rev & IMG_IR_DESIGNER) >> IMG_IR_DESIGNER_SHIFT,
  68                  (core_rev & IMG_IR_MAJOR_REV) >> IMG_IR_MAJOR_REV_SHIFT,
  69                  (core_rev & IMG_IR_MINOR_REV) >> IMG_IR_MINOR_REV_SHIFT,
  70                  (core_rev & IMG_IR_MAINT_REV) >> IMG_IR_MAINT_REV_SHIFT);
  71         dev_info(priv->dev, "Modes:%s%s\n",
  72                  img_ir_hw_enabled(&priv->hw) ? " hardware" : "",
  73                  img_ir_raw_enabled(&priv->raw) ? " raw" : "");
  74 }
  75
  76 static int img_ir_probe(struct platform_device *pdev)
  77 {
  78         struct img_ir_priv *priv;
  79         int irq, error, error2;
  80
  81         /* Get resources from platform device */
  82         irq = platform_get_irq(pdev, 0);
  83         if (irq < 0)
  84                 return irq;
  85
  86         /* Private driver data */
  87         priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  88         if (!priv)
  89                 return -ENOMEM;
  90
  91         platform_set_drvdata(pdev, priv);
  92         priv->dev = &pdev->dev;
  93         spin_lock_init(&priv->lock);
  94
  95         /* Ioremap the registers */
  96         priv->reg_base = devm_platform_ioremap_resource(pdev, 0);
  97         if (IS_ERR(priv->reg_base))
  98                 return PTR_ERR(priv->reg_base);
  99
 100         /* Get core clock */
 101         priv->clk = devm_clk_get(&pdev->dev, "core");
 102         if (IS_ERR(priv->clk))
 103                 dev_warn(&pdev->dev, "cannot get core clock resource\n");
 104
 105         /* Get sys clock */
 106         priv->sys_clk = devm_clk_get(&pdev->dev, "sys");
 107         if (IS_ERR(priv->sys_clk))
 108                 dev_warn(&pdev->dev, "cannot get sys clock resource\n");
 109         /*
 110          * Enabling the system clock before the register interface is
 111          * accessed. ISR shouldn't get called with Sys Clock disabled,
 112          * hence exiting probe with an error.
 113          */
 114         if (!IS_ERR(priv->sys_clk)) {
 115                 error = clk_prepare_enable(priv->sys_clk);
 116                 if (error) {
 117                         dev_err(&pdev->dev, "cannot enable sys clock\n");
 118                         return error;
 119                 }
 120         }
 121
 122         /* Set up raw & hw decoder */
 123         error = img_ir_probe_raw(priv);
 124         error2 = img_ir_probe_hw(priv);
 125         if (error && error2) {
 126                 if (error == -ENODEV)
 127                         error = error2;
 128                 goto err_probe;
 129         }
 130
 131         /* Get the IRQ */
 132         priv->irq = irq;
 133         error = request_irq(priv->irq, img_ir_isr, 0, "img-ir", priv);
 134         if (error) {
 135                 dev_err(&pdev->dev, "cannot register IRQ %u\n",
 136                         priv->irq);
 137                 error = -EIO;
 138                 goto err_irq;
 139         }
 140
 141         img_ir_ident(priv);
 142         img_ir_setup(priv);
 143
 144         return 0;
 145
 146 err_irq:
 147         img_ir_remove_hw(priv);
 148         img_ir_remove_raw(priv);
 149 err_probe:
 150         if (!IS_ERR(priv->sys_clk))
 151                 clk_disable_unprepare(priv->sys_clk);
 152         return error;
 153 }
 154
 155 static void img_ir_remove(struct platform_device *pdev)
 156 {
 157         struct img_ir_priv *priv = platform_get_drvdata(pdev);
 158
 159         free_irq(priv->irq, priv);
 160         img_ir_remove_hw(priv);
 161         img_ir_remove_raw(priv);
 162
 163         if (!IS_ERR(priv->clk))
 164                 clk_disable_unprepare(priv->clk);
 165         if (!IS_ERR(priv->sys_clk))
 166                 clk_disable_unprepare(priv->sys_clk);
 167 }
 168
 169 static SIMPLE_DEV_PM_OPS(img_ir_pmops, img_ir_suspend, img_ir_resume);
 170
 171 static const struct of_device_id img_ir_match[] = {
 172         { .compatible = "img,ir-rev1" },
 173         {}
 174 };
 175 MODULE_DEVICE_TABLE(of, img_ir_match);
 176
 177 static struct platform_driver img_ir_driver = {
 178         .driver = {
 179                 .name = "img-ir",
 180                 .of_match_table = img_ir_match,
 181                 .pm = &img_ir_pmops,
 182         },
 183         .probe = img_ir_probe,
 184         .remove_new = img_ir_remove,
 185 };
 186
 187 module_platform_driver(img_ir_driver);
 188
 189 MODULE_AUTHOR("Imagination Technologies Ltd.");
 190 MODULE_DESCRIPTION("ImgTec IR");
 191 MODULE_LICENSE("GPL");