drivers/media/platform/xilinx/xilinx-scenechange.c

   1 //SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Xilinx Scene Change Detection driver
   4  *
   5  * Copyright (C) 2018 Xilinx, Inc.
   6  *
   7  * Authors: Anand Ashok Dumbre <anand.ashok.dumbre@xilinx.com>
   8  *          Satish Kumar Nagireddy <satish.nagireddy.nagireddy@xilinx.com>
   9  */
  10
  11 #include "xilinx-scenechange.h"
  12
  13 #define XSCD_RESET_DEASSERT     (0)
  14 #define XSCD_RESET_ASSERT       (1)
  15
  16 static irqreturn_t xscd_irq_handler(int irq, void *data)
  17 {
  18         struct xscd_device *xscd = (struct xscd_device *)data;
  19         unsigned int i;
  20         u32 status;
  21
  22         status = xscd_read(xscd->iomem, XSCD_ISR_OFFSET);
  23         if (!(status & XSCD_IE_AP_DONE))
  24                 return IRQ_NONE;
  25
  26         xscd_write(xscd->iomem, XSCD_ISR_OFFSET, XSCD_IE_AP_DONE);
  27
  28         for (i = 0; i < xscd->num_streams; ++i)
  29                 xscd_chan_irq_handler(xscd->chans[i]);
  30
  31         xscd_dma_irq_handler(xscd);
  32
  33         return IRQ_HANDLED;
  34 }
  35
  36 static int xscd_init_resources(struct xscd_device *xscd)
  37 {
  38         struct platform_device *pdev = to_platform_device(xscd->dev);
  39         struct resource *res;
  40
  41         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  42         xscd->iomem = devm_ioremap_resource(xscd->dev, res);
  43         if (IS_ERR(xscd->iomem))
  44                 return PTR_ERR(xscd->iomem);
  45
  46         xscd->irq = platform_get_irq(pdev, 0);
  47         if (xscd->irq < 0) {
  48                 dev_err(xscd->dev, "No valid irq found\n");
  49                 return -EINVAL;
  50         }
  51
  52         xscd->clk = devm_clk_get(xscd->dev, NULL);
  53         if (IS_ERR(xscd->clk))
  54                 return PTR_ERR(xscd->clk);
  55
  56         clk_prepare_enable(xscd->clk);
  57         return 0;
  58 }
  59
  60 static int xscd_parse_of(struct xscd_device *xscd)
  61 {
  62         struct device *dev = xscd->dev;
  63         struct device_node *node = xscd->dev->of_node;
  64         int ret;
  65
  66         xscd->memory_based = of_property_read_bool(node, "xlnx,memorybased");
  67         xscd->rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
  68         if (IS_ERR(xscd->rst_gpio)) {
  69                 if (PTR_ERR(xscd->rst_gpio) != -EPROBE_DEFER)
  70                         dev_err(dev, "Reset GPIO not setup in DT\n");
  71
  72                 return PTR_ERR(xscd->rst_gpio);
  73         }
  74
  75         ret = of_property_read_u32(node, "xlnx,numstreams",
  76                                    &xscd->num_streams);
  77         if (ret < 0)
  78                 return ret;
  79
  80         if (!xscd->memory_based && xscd->num_streams != 1) {
  81                 dev_err(dev, "Stream-based mode only supports one stream\n");
  82                 return -EINVAL;
  83         }
  84
  85         return 0;
  86 }
  87
  88 static int xscd_probe(struct platform_device *pdev)
  89 {
  90         struct xscd_device *xscd;
  91         struct device_node *subdev_node;
  92         unsigned int id;
  93         int ret;
  94
  95         xscd = devm_kzalloc(&pdev->dev, sizeof(*xscd), GFP_KERNEL);
  96         if (!xscd)
  97                 return -ENOMEM;
  98
  99         xscd->dev = &pdev->dev;
 100         platform_set_drvdata(pdev, xscd);
 101
 102         ret = xscd_parse_of(xscd);
 103         if (ret < 0)
 104                 return ret;
 105
 106         ret = xscd_init_resources(xscd);
 107         if (ret < 0)
 108                 return ret;
 109
 110         /* Reset Scene Change Detection IP */
 111         gpiod_set_value_cansleep(xscd->rst_gpio, XSCD_RESET_ASSERT);
 112         gpiod_set_value_cansleep(xscd->rst_gpio, XSCD_RESET_DEASSERT);
 113
 114         id = 0;
 115         for_each_child_of_node(xscd->dev->of_node, subdev_node) {
 116                 if (id >= xscd->num_streams) {
 117                         dev_warn(&pdev->dev,
 118                                  "Too many channels, limiting to %u\n",
 119                                  xscd->num_streams);
 120                         of_node_put(subdev_node);
 121                         break;
 122                 }
 123
 124                 ret = xscd_chan_init(xscd, id, subdev_node);
 125                 if (ret < 0) {
 126                         dev_err(&pdev->dev, "Failed to initialize channel %u\n",
 127                                 id);
 128                         return ret;
 129                 }
 130
 131                 id++;
 132         }
 133
 134         ret = xscd_dma_init(xscd);
 135         if (ret < 0)
 136                 dev_err(&pdev->dev, "Failed to initialize the DMA\n");
 137
 138         ret = devm_request_irq(xscd->dev, xscd->irq, xscd_irq_handler,
 139                                IRQF_SHARED, dev_name(xscd->dev), xscd);
 140         if (ret < 0)
 141                 dev_err(&pdev->dev, "Failed to request IRQ\n");
 142
 143         dev_info(xscd->dev, "scene change detect device found!\n");
 144         return 0;
 145 }
 146
 147 static int xscd_remove(struct platform_device *pdev)
 148 {
 149         struct xscd_device *xscd = platform_get_drvdata(pdev);
 150
 151         xscd_dma_cleanup(xscd);
 152         clk_disable_unprepare(xscd->clk);
 153
 154         return 0;
 155 }
 156
 157 static const struct of_device_id xscd_of_id_table[] = {
 158         { .compatible = "xlnx,v-scd" },
 159         { }
 160 };
 161 MODULE_DEVICE_TABLE(of, xscd_of_id_table);
 162
 163 static struct platform_driver xscd_driver = {
 164         .driver = {
 165                 .name           = "xilinx-scd",
 166                 .of_match_table = xscd_of_id_table,
 167         },
 168         .probe                  = xscd_probe,
 169         .remove                 = xscd_remove,
 170 };
 171
 172 module_platform_driver(xscd_driver);
 173
 174 MODULE_AUTHOR("Xilinx Inc.");
 175 MODULE_DESCRIPTION("Xilinx Scene Change Detection");
 176 MODULE_LICENSE("GPL v2");