drivers/media/video/soc_camera_platform.c

   1 /*
   2  * Generic Platform Camera Driver
   3  *
   4  * Copyright (C) 2008 Magnus Damm
   5  * Based on mt9m001 driver,
   6  * Copyright (C) 2008, Guennadi Liakhovetski <kernel@pengutronix.de>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/init.h>
  14 #include <linux/module.h>
  15 #include <linux/slab.h>
  16 #include <linux/delay.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/videodev2.h>
  19 #include <media/v4l2-subdev.h>
  20 #include <media/soc_camera.h>
  21 #include <media/soc_camera_platform.h>
  22
  23 struct soc_camera_platform_priv {
  24         struct v4l2_subdev subdev;
  25 };
  26
  27 static struct soc_camera_platform_priv *get_priv(struct platform_device *pdev)
  28 {
  29         struct v4l2_subdev *subdev = platform_get_drvdata(pdev);
  30         return container_of(subdev, struct soc_camera_platform_priv, subdev);
  31 }
  32
  33 static struct soc_camera_platform_info *get_info(struct soc_camera_device *icd)
  34 {
  35         struct platform_device *pdev =
  36                 to_platform_device(to_soc_camera_control(icd));
  37         return pdev->dev.platform_data;
  38 }
  39
  40 static int soc_camera_platform_s_stream(struct v4l2_subdev *sd, int enable)
  41 {
  42         struct soc_camera_platform_info *p = v4l2_get_subdevdata(sd);
  43         return p->set_capture(p, enable);
  44 }
  45
  46 static int soc_camera_platform_set_bus_param(struct soc_camera_device *icd,
  47                                              unsigned long flags)
  48 {
  49         return 0;
  50 }
  51
  52 static unsigned long
  53 soc_camera_platform_query_bus_param(struct soc_camera_device *icd)
  54 {
  55         struct soc_camera_platform_info *p = get_info(icd);
  56         return p->bus_param;
  57 }
  58
  59 static int soc_camera_platform_try_fmt(struct v4l2_subdev *sd,
  60                                        struct v4l2_mbus_framefmt *mf)
  61 {
  62         struct soc_camera_platform_info *p = v4l2_get_subdevdata(sd);
  63
  64         mf->width       = p->format.width;
  65         mf->height      = p->format.height;
  66         mf->code        = p->format.code;
  67         mf->colorspace  = p->format.colorspace;
  68
  69         return 0;
  70 }
  71
  72 static struct v4l2_subdev_core_ops platform_subdev_core_ops;
  73
  74 static int soc_camera_platform_enum_fmt(struct v4l2_subdev *sd, int index,
  75                                         enum v4l2_mbus_pixelcode *code)
  76 {
  77         struct soc_camera_platform_info *p = v4l2_get_subdevdata(sd);
  78
  79         if (index)
  80                 return -EINVAL;
  81
  82         *code = p->format.code;
  83         return 0;
  84 }
  85
  86 static struct v4l2_subdev_video_ops platform_subdev_video_ops = {
  87         .s_stream       = soc_camera_platform_s_stream,
  88         .try_mbus_fmt   = soc_camera_platform_try_fmt,
  89         .enum_mbus_fmt  = soc_camera_platform_enum_fmt,
  90 };
  91
  92 static struct v4l2_subdev_ops platform_subdev_ops = {
  93         .core   = &platform_subdev_core_ops,
  94         .video  = &platform_subdev_video_ops,
  95 };
  96
  97 static struct soc_camera_ops soc_camera_platform_ops = {
  98         .set_bus_param          = soc_camera_platform_set_bus_param,
  99         .query_bus_param        = soc_camera_platform_query_bus_param,
 100 };
 101
 102 static int soc_camera_platform_probe(struct platform_device *pdev)
 103 {
 104         struct soc_camera_host *ici;
 105         struct soc_camera_platform_priv *priv;
 106         struct soc_camera_platform_info *p = pdev->dev.platform_data;
 107         struct soc_camera_device *icd;
 108         int ret;
 109
 110         if (!p)
 111                 return -EINVAL;
 112
 113         if (!p->dev) {
 114                 dev_err(&pdev->dev,
 115                         "Platform has not set soc_camera_device pointer!\n");
 116                 return -EINVAL;
 117         }
 118
 119         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 120         if (!priv)
 121                 return -ENOMEM;
 122
 123         icd = to_soc_camera_dev(p->dev);
 124
 125         /* soc-camera convention: control's drvdata points to the subdev */
 126         platform_set_drvdata(pdev, &priv->subdev);
 127         /* Set the control device reference */
 128         dev_set_drvdata(&icd->dev, &pdev->dev);
 129
 130         icd->ops = &soc_camera_platform_ops;
 131
 132         ici = to_soc_camera_host(icd->dev.parent);
 133
 134         v4l2_subdev_init(&priv->subdev, &platform_subdev_ops);
 135         v4l2_set_subdevdata(&priv->subdev, p);
 136         strncpy(priv->subdev.name, dev_name(&pdev->dev), V4L2_SUBDEV_NAME_SIZE);
 137
 138         ret = v4l2_device_register_subdev(&ici->v4l2_dev, &priv->subdev);
 139         if (ret)
 140                 goto evdrs;
 141
 142         return ret;
 143
 144 evdrs:
 145         icd->ops = NULL;
 146         platform_set_drvdata(pdev, NULL);
 147         kfree(priv);
 148         return ret;
 149 }
 150
 151 static int soc_camera_platform_remove(struct platform_device *pdev)
 152 {
 153         struct soc_camera_platform_priv *priv = get_priv(pdev);
 154         struct soc_camera_platform_info *p = pdev->dev.platform_data;
 155         struct soc_camera_device *icd = to_soc_camera_dev(p->dev);
 156
 157         v4l2_device_unregister_subdev(&priv->subdev);
 158         icd->ops = NULL;
 159         platform_set_drvdata(pdev, NULL);
 160         kfree(priv);
 161         return 0;
 162 }
 163
 164 static struct platform_driver soc_camera_platform_driver = {
 165         .driver         = {
 166                 .name   = "soc_camera_platform",
 167                 .owner  = THIS_MODULE,
 168         },
 169         .probe          = soc_camera_platform_probe,
 170         .remove         = soc_camera_platform_remove,
 171 };
 172
 173 static int __init soc_camera_platform_module_init(void)
 174 {
 175         return platform_driver_register(&soc_camera_platform_driver);
 176 }
 177
 178 static void __exit soc_camera_platform_module_exit(void)
 179 {
 180         platform_driver_unregister(&soc_camera_platform_driver);
 181 }
 182
 183 module_init(soc_camera_platform_module_init);
 184 module_exit(soc_camera_platform_module_exit);
 185
 186 MODULE_DESCRIPTION("SoC Camera Platform driver");
 187 MODULE_AUTHOR("Magnus Damm");
 188 MODULE_LICENSE("GPL v2");
 189 MODULE_ALIAS("platform:soc_camera_platform");