drivers/media/video/marvell-ccic/mmp-driver.c

   1 /*
   2  * Support for the camera device found on Marvell MMP processors; known
   3  * to work with the Armada 610 as used in the OLPC 1.75 system.
   4  *
   5  * Copyright 2011 Jonathan Corbet <corbet@lwn.net>
   6  *
   7  * This file may be distributed under the terms of the GNU General
   8  * Public License, version 2.
   9  */
  10
  11 #include <linux/init.h>
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/i2c.h>
  15 #include <linux/i2c-gpio.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/slab.h>
  19 #include <linux/videodev2.h>
  20 #include <media/v4l2-device.h>
  21 #include <media/v4l2-chip-ident.h>
  22 #include <media/mmp-camera.h>
  23 #include <linux/device.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/gpio.h>
  26 #include <linux/io.h>
  27 #include <linux/delay.h>
  28 #include <linux/list.h>
  29
  30 #include "mcam-core.h"
  31
  32 MODULE_ALIAS("platform:mmp-camera");
  33 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
  34 MODULE_LICENSE("GPL");
  35
  36 struct mmp_camera {
  37         void *power_regs;
  38         struct platform_device *pdev;
  39         struct mcam_camera mcam;
  40         struct list_head devlist;
  41         int irq;
  42 };
  43
  44 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
  45 {
  46         return container_of(mcam, struct mmp_camera, mcam);
  47 }
  48
  49 /*
  50  * A silly little infrastructure so we can keep track of our devices.
  51  * Chances are that we will never have more than one of them, but
  52  * the Armada 610 *does* have two controllers...
  53  */
  54
  55 static LIST_HEAD(mmpcam_devices);
  56 static struct mutex mmpcam_devices_lock;
  57
  58 static void mmpcam_add_device(struct mmp_camera *cam)
  59 {
  60         mutex_lock(&mmpcam_devices_lock);
  61         list_add(&cam->devlist, &mmpcam_devices);
  62         mutex_unlock(&mmpcam_devices_lock);
  63 }
  64
  65 static void mmpcam_remove_device(struct mmp_camera *cam)
  66 {
  67         mutex_lock(&mmpcam_devices_lock);
  68         list_del(&cam->devlist);
  69         mutex_unlock(&mmpcam_devices_lock);
  70 }
  71
  72 /*
  73  * Platform dev remove passes us a platform_device, and there's
  74  * no handy unused drvdata to stash a backpointer in.  So just
  75  * dig it out of our list.
  76  */
  77 static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev)
  78 {
  79         struct mmp_camera *cam;
  80
  81         mutex_lock(&mmpcam_devices_lock);
  82         list_for_each_entry(cam, &mmpcam_devices, devlist) {
  83                 if (cam->pdev == pdev) {
  84                         mutex_unlock(&mmpcam_devices_lock);
  85                         return cam;
  86                 }
  87         }
  88         mutex_unlock(&mmpcam_devices_lock);
  89         return NULL;
  90 }
  91
  92
  93
  94
  95 /*
  96  * Power-related registers; this almost certainly belongs
  97  * somewhere else.
  98  *
  99  * ARMADA 610 register manual, sec 7.2.1, p1842.
 100  */
 101 #define CPU_SUBSYS_PMU_BASE     0xd4282800
 102 #define REG_CCIC_DCGCR          0x28    /* CCIC dyn clock gate ctrl reg */
 103 #define REG_CCIC_CRCR           0x50    /* CCIC clk reset ctrl reg      */
 104
 105 /*
 106  * Power control.
 107  */
 108 static void mmpcam_power_up(struct mcam_camera *mcam)
 109 {
 110         struct mmp_camera *cam = mcam_to_cam(mcam);
 111         struct mmp_camera_platform_data *pdata;
 112 /*
 113  * Turn on power and clocks to the controller.
 114  */
 115         iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
 116         iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
 117         mdelay(1);
 118 /*
 119  * Provide power to the sensor.
 120  */
 121         mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
 122         pdata = cam->pdev->dev.platform_data;
 123         gpio_set_value(pdata->sensor_power_gpio, 1);
 124         mdelay(5);
 125         mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
 126         gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
 127         mdelay(5);
 128         gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
 129         mdelay(5);
 130 }
 131
 132 static void mmpcam_power_down(struct mcam_camera *mcam)
 133 {
 134         struct mmp_camera *cam = mcam_to_cam(mcam);
 135         struct mmp_camera_platform_data *pdata;
 136 /*
 137  * Turn off clocks and set reset lines
 138  */
 139         iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
 140         iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
 141 /*
 142  * Shut down the sensor.
 143  */
 144         pdata = cam->pdev->dev.platform_data;
 145         gpio_set_value(pdata->sensor_power_gpio, 0);
 146         gpio_set_value(pdata->sensor_reset_gpio, 0);
 147 }
 148
 149
 150 static irqreturn_t mmpcam_irq(int irq, void *data)
 151 {
 152         struct mcam_camera *mcam = data;
 153         unsigned int irqs, handled;
 154
 155         spin_lock(&mcam->dev_lock);
 156         irqs = mcam_reg_read(mcam, REG_IRQSTAT);
 157         handled = mccic_irq(mcam, irqs);
 158         spin_unlock(&mcam->dev_lock);
 159         return IRQ_RETVAL(handled);
 160 }
 161
 162
 163 static int mmpcam_probe(struct platform_device *pdev)
 164 {
 165         struct mmp_camera *cam;
 166         struct mcam_camera *mcam;
 167         struct resource *res;
 168         struct mmp_camera_platform_data *pdata;
 169         int ret;
 170
 171         cam = kzalloc(sizeof(*cam), GFP_KERNEL);
 172         if (cam == NULL)
 173                 return -ENOMEM;
 174         cam->pdev = pdev;
 175         INIT_LIST_HEAD(&cam->devlist);
 176
 177         mcam = &cam->mcam;
 178         mcam->platform = MHP_Armada610;
 179         mcam->plat_power_up = mmpcam_power_up;
 180         mcam->plat_power_down = mmpcam_power_down;
 181         mcam->dev = &pdev->dev;
 182         mcam->use_smbus = 0;
 183         mcam->chip_id = V4L2_IDENT_ARMADA610;
 184         mcam->buffer_mode = B_DMA_sg;
 185         spin_lock_init(&mcam->dev_lock);
 186         /*
 187          * Get our I/O memory.
 188          */
 189         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 190         if (res == NULL) {
 191                 dev_err(&pdev->dev, "no iomem resource!\n");
 192                 ret = -ENODEV;
 193                 goto out_free;
 194         }
 195         mcam->regs = ioremap(res->start, resource_size(res));
 196         if (mcam->regs == NULL) {
 197                 dev_err(&pdev->dev, "MMIO ioremap fail\n");
 198                 ret = -ENODEV;
 199                 goto out_free;
 200         }
 201         /*
 202          * Power/clock memory is elsewhere; get it too.  Perhaps this
 203          * should really be managed outside of this driver?
 204          */
 205         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 206         if (res == NULL) {
 207                 dev_err(&pdev->dev, "no power resource!\n");
 208                 ret = -ENODEV;
 209                 goto out_unmap1;
 210         }
 211         cam->power_regs = ioremap(res->start, resource_size(res));
 212         if (cam->power_regs == NULL) {
 213                 dev_err(&pdev->dev, "power MMIO ioremap fail\n");
 214                 ret = -ENODEV;
 215                 goto out_unmap1;
 216         }
 217         /*
 218          * Find the i2c adapter.  This assumes, of course, that the
 219          * i2c bus is already up and functioning.
 220          */
 221         pdata = pdev->dev.platform_data;
 222         mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
 223         if (mcam->i2c_adapter == NULL) {
 224                 ret = -ENODEV;
 225                 dev_err(&pdev->dev, "No i2c adapter\n");
 226                 goto out_unmap2;
 227         }
 228         /*
 229          * Sensor GPIO pins.
 230          */
 231         ret = gpio_request(pdata->sensor_power_gpio, "cam-power");
 232         if (ret) {
 233                 dev_err(&pdev->dev, "Can't get sensor power gpio %d",
 234                                 pdata->sensor_power_gpio);
 235                 goto out_unmap2;
 236         }
 237         gpio_direction_output(pdata->sensor_power_gpio, 0);
 238         ret = gpio_request(pdata->sensor_reset_gpio, "cam-reset");
 239         if (ret) {
 240                 dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
 241                                 pdata->sensor_reset_gpio);
 242                 goto out_gpio;
 243         }
 244         gpio_direction_output(pdata->sensor_reset_gpio, 0);
 245         /*
 246          * Power the device up and hand it off to the core.
 247          */
 248         mmpcam_power_up(mcam);
 249         ret = mccic_register(mcam);
 250         if (ret)
 251                 goto out_gpio2;
 252         /*
 253          * Finally, set up our IRQ now that the core is ready to
 254          * deal with it.
 255          */
 256         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 257         if (res == NULL) {
 258                 ret = -ENODEV;
 259                 goto out_unregister;
 260         }
 261         cam->irq = res->start;
 262         ret = request_irq(cam->irq, mmpcam_irq, IRQF_SHARED,
 263                         "mmp-camera", mcam);
 264         if (ret == 0) {
 265                 mmpcam_add_device(cam);
 266                 return 0;
 267         }
 268
 269 out_unregister:
 270         mccic_shutdown(mcam);
 271 out_gpio2:
 272         mmpcam_power_down(mcam);
 273         gpio_free(pdata->sensor_reset_gpio);
 274 out_gpio:
 275         gpio_free(pdata->sensor_power_gpio);
 276 out_unmap2:
 277         iounmap(cam->power_regs);
 278 out_unmap1:
 279         iounmap(mcam->regs);
 280 out_free:
 281         kfree(cam);
 282         return ret;
 283 }
 284
 285
 286 static int mmpcam_remove(struct mmp_camera *cam)
 287 {
 288         struct mcam_camera *mcam = &cam->mcam;
 289         struct mmp_camera_platform_data *pdata;
 290
 291         mmpcam_remove_device(cam);
 292         free_irq(cam->irq, mcam);
 293         mccic_shutdown(mcam);
 294         mmpcam_power_down(mcam);
 295         pdata = cam->pdev->dev.platform_data;
 296         gpio_free(pdata->sensor_reset_gpio);
 297         gpio_free(pdata->sensor_power_gpio);
 298         iounmap(cam->power_regs);
 299         iounmap(mcam->regs);
 300         kfree(cam);
 301         return 0;
 302 }
 303
 304 static int mmpcam_platform_remove(struct platform_device *pdev)
 305 {
 306         struct mmp_camera *cam = mmpcam_find_device(pdev);
 307
 308         if (cam == NULL)
 309                 return -ENODEV;
 310         return mmpcam_remove(cam);
 311 }
 312
 313
 314 static struct platform_driver mmpcam_driver = {
 315         .probe          = mmpcam_probe,
 316         .remove         = mmpcam_platform_remove,
 317         .driver = {
 318                 .name   = "mmp-camera",
 319                 .owner  = THIS_MODULE
 320         }
 321 };
 322
 323
 324 static int __init mmpcam_init_module(void)
 325 {
 326         mutex_init(&mmpcam_devices_lock);
 327         return platform_driver_register(&mmpcam_driver);
 328 }
 329
 330 static void __exit mmpcam_exit_module(void)
 331 {
 332         platform_driver_unregister(&mmpcam_driver);
 333         /*
 334          * platform_driver_unregister() should have emptied the list
 335          */
 336         if (!list_empty(&mmpcam_devices))
 337                 printk(KERN_ERR "mmp_camera leaving devices behind\n");
 338 }
 339
 340 module_init(mmpcam_init_module);
 341 module_exit(mmpcam_exit_module);