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 #include <linux/pm.h>
  30
  31 #include "mcam-core.h"
  32
  33 MODULE_ALIAS("platform:mmp-camera");
  34 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
  35 MODULE_LICENSE("GPL");
  36
  37 struct mmp_camera {
  38         void *power_regs;
  39         struct platform_device *pdev;
  40         struct mcam_camera mcam;
  41         struct list_head devlist;
  42         int irq;
  43 };
  44
  45 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
  46 {
  47         return container_of(mcam, struct mmp_camera, mcam);
  48 }
  49
  50 /*
  51  * A silly little infrastructure so we can keep track of our devices.
  52  * Chances are that we will never have more than one of them, but
  53  * the Armada 610 *does* have two controllers...
  54  */
  55
  56 static LIST_HEAD(mmpcam_devices);
  57 static struct mutex mmpcam_devices_lock;
  58
  59 static void mmpcam_add_device(struct mmp_camera *cam)
  60 {
  61         mutex_lock(&mmpcam_devices_lock);
  62         list_add(&cam->devlist, &mmpcam_devices);
  63         mutex_unlock(&mmpcam_devices_lock);
  64 }
  65
  66 static void mmpcam_remove_device(struct mmp_camera *cam)
  67 {
  68         mutex_lock(&mmpcam_devices_lock);
  69         list_del(&cam->devlist);
  70         mutex_unlock(&mmpcam_devices_lock);
  71 }
  72
  73 /*
  74  * Platform dev remove passes us a platform_device, and there's
  75  * no handy unused drvdata to stash a backpointer in.  So just
  76  * dig it out of our list.
  77  */
  78 static struct mmp_camera *mmpcam_find_device(struct platform_device *pdev)
  79 {
  80         struct mmp_camera *cam;
  81
  82         mutex_lock(&mmpcam_devices_lock);
  83         list_for_each_entry(cam, &mmpcam_devices, devlist) {
  84                 if (cam->pdev == pdev) {
  85                         mutex_unlock(&mmpcam_devices_lock);
  86                         return cam;
  87                 }
  88         }
  89         mutex_unlock(&mmpcam_devices_lock);
  90         return NULL;
  91 }
  92
  93
  94
  95
  96 /*
  97  * Power-related registers; this almost certainly belongs
  98  * somewhere else.
  99  *
 100  * ARMADA 610 register manual, sec 7.2.1, p1842.
 101  */
 102 #define CPU_SUBSYS_PMU_BASE     0xd4282800
 103 #define REG_CCIC_DCGCR          0x28    /* CCIC dyn clock gate ctrl reg */
 104 #define REG_CCIC_CRCR           0x50    /* CCIC clk reset ctrl reg      */
 105
 106 /*
 107  * Power control.
 108  */
 109 static void mmpcam_power_up_ctlr(struct mmp_camera *cam)
 110 {
 111         iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
 112         iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
 113         mdelay(1);
 114 }
 115
 116 static void mmpcam_power_up(struct mcam_camera *mcam)
 117 {
 118         struct mmp_camera *cam = mcam_to_cam(mcam);
 119         struct mmp_camera_platform_data *pdata;
 120 /*
 121  * Turn on power and clocks to the controller.
 122  */
 123         mmpcam_power_up_ctlr(cam);
 124 /*
 125  * Provide power to the sensor.
 126  */
 127         mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
 128         pdata = cam->pdev->dev.platform_data;
 129         gpio_set_value(pdata->sensor_power_gpio, 1);
 130         mdelay(5);
 131         mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
 132         gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
 133         mdelay(5);
 134         gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
 135         mdelay(5);
 136 }
 137
 138 static void mmpcam_power_down(struct mcam_camera *mcam)
 139 {
 140         struct mmp_camera *cam = mcam_to_cam(mcam);
 141         struct mmp_camera_platform_data *pdata;
 142 /*
 143  * Turn off clocks and set reset lines
 144  */
 145         iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
 146         iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
 147 /*
 148  * Shut down the sensor.
 149  */
 150         pdata = cam->pdev->dev.platform_data;
 151         gpio_set_value(pdata->sensor_power_gpio, 0);
 152         gpio_set_value(pdata->sensor_reset_gpio, 0);
 153 }
 154
 155
 156 static irqreturn_t mmpcam_irq(int irq, void *data)
 157 {
 158         struct mcam_camera *mcam = data;
 159         unsigned int irqs, handled;
 160
 161         spin_lock(&mcam->dev_lock);
 162         irqs = mcam_reg_read(mcam, REG_IRQSTAT);
 163         handled = mccic_irq(mcam, irqs);
 164         spin_unlock(&mcam->dev_lock);
 165         return IRQ_RETVAL(handled);
 166 }
 167
 168
 169 static int mmpcam_probe(struct platform_device *pdev)
 170 {
 171         struct mmp_camera *cam;
 172         struct mcam_camera *mcam;
 173         struct resource *res;
 174         struct mmp_camera_platform_data *pdata;
 175         int ret;
 176
 177         cam = kzalloc(sizeof(*cam), GFP_KERNEL);
 178         if (cam == NULL)
 179                 return -ENOMEM;
 180         cam->pdev = pdev;
 181         INIT_LIST_HEAD(&cam->devlist);
 182
 183         mcam = &cam->mcam;
 184         mcam->platform = MHP_Armada610;
 185         mcam->plat_power_up = mmpcam_power_up;
 186         mcam->plat_power_down = mmpcam_power_down;
 187         mcam->dev = &pdev->dev;
 188         mcam->use_smbus = 0;
 189         mcam->chip_id = V4L2_IDENT_ARMADA610;
 190         mcam->buffer_mode = B_DMA_sg;
 191         spin_lock_init(&mcam->dev_lock);
 192         /*
 193          * Get our I/O memory.
 194          */
 195         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 196         if (res == NULL) {
 197                 dev_err(&pdev->dev, "no iomem resource!\n");
 198                 ret = -ENODEV;
 199                 goto out_free;
 200         }
 201         mcam->regs = ioremap(res->start, resource_size(res));
 202         if (mcam->regs == NULL) {
 203                 dev_err(&pdev->dev, "MMIO ioremap fail\n");
 204                 ret = -ENODEV;
 205                 goto out_free;
 206         }
 207         /*
 208          * Power/clock memory is elsewhere; get it too.  Perhaps this
 209          * should really be managed outside of this driver?
 210          */
 211         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 212         if (res == NULL) {
 213                 dev_err(&pdev->dev, "no power resource!\n");
 214                 ret = -ENODEV;
 215                 goto out_unmap1;
 216         }
 217         cam->power_regs = ioremap(res->start, resource_size(res));
 218         if (cam->power_regs == NULL) {
 219                 dev_err(&pdev->dev, "power MMIO ioremap fail\n");
 220                 ret = -ENODEV;
 221                 goto out_unmap1;
 222         }
 223         /*
 224          * Find the i2c adapter.  This assumes, of course, that the
 225          * i2c bus is already up and functioning.
 226          */
 227         pdata = pdev->dev.platform_data;
 228         mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
 229         if (mcam->i2c_adapter == NULL) {
 230                 ret = -ENODEV;
 231                 dev_err(&pdev->dev, "No i2c adapter\n");
 232                 goto out_unmap2;
 233         }
 234         /*
 235          * Sensor GPIO pins.
 236          */
 237         ret = gpio_request(pdata->sensor_power_gpio, "cam-power");
 238         if (ret) {
 239                 dev_err(&pdev->dev, "Can't get sensor power gpio %d",
 240                                 pdata->sensor_power_gpio);
 241                 goto out_unmap2;
 242         }
 243         gpio_direction_output(pdata->sensor_power_gpio, 0);
 244         ret = gpio_request(pdata->sensor_reset_gpio, "cam-reset");
 245         if (ret) {
 246                 dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
 247                                 pdata->sensor_reset_gpio);
 248                 goto out_gpio;
 249         }
 250         gpio_direction_output(pdata->sensor_reset_gpio, 0);
 251         /*
 252          * Power the device up and hand it off to the core.
 253          */
 254         mmpcam_power_up(mcam);
 255         ret = mccic_register(mcam);
 256         if (ret)
 257                 goto out_gpio2;
 258         /*
 259          * Finally, set up our IRQ now that the core is ready to
 260          * deal with it.
 261          */
 262         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 263         if (res == NULL) {
 264                 ret = -ENODEV;
 265                 goto out_unregister;
 266         }
 267         cam->irq = res->start;
 268         ret = request_irq(cam->irq, mmpcam_irq, IRQF_SHARED,
 269                         "mmp-camera", mcam);
 270         if (ret == 0) {
 271                 mmpcam_add_device(cam);
 272                 return 0;
 273         }
 274
 275 out_unregister:
 276         mccic_shutdown(mcam);
 277 out_gpio2:
 278         mmpcam_power_down(mcam);
 279         gpio_free(pdata->sensor_reset_gpio);
 280 out_gpio:
 281         gpio_free(pdata->sensor_power_gpio);
 282 out_unmap2:
 283         iounmap(cam->power_regs);
 284 out_unmap1:
 285         iounmap(mcam->regs);
 286 out_free:
 287         kfree(cam);
 288         return ret;
 289 }
 290
 291
 292 static int mmpcam_remove(struct mmp_camera *cam)
 293 {
 294         struct mcam_camera *mcam = &cam->mcam;
 295         struct mmp_camera_platform_data *pdata;
 296
 297         mmpcam_remove_device(cam);
 298         free_irq(cam->irq, mcam);
 299         mccic_shutdown(mcam);
 300         mmpcam_power_down(mcam);
 301         pdata = cam->pdev->dev.platform_data;
 302         gpio_free(pdata->sensor_reset_gpio);
 303         gpio_free(pdata->sensor_power_gpio);
 304         iounmap(cam->power_regs);
 305         iounmap(mcam->regs);
 306         kfree(cam);
 307         return 0;
 308 }
 309
 310 static int mmpcam_platform_remove(struct platform_device *pdev)
 311 {
 312         struct mmp_camera *cam = mmpcam_find_device(pdev);
 313
 314         if (cam == NULL)
 315                 return -ENODEV;
 316         return mmpcam_remove(cam);
 317 }
 318
 319 /*
 320  * Suspend/resume support.
 321  */
 322 #ifdef CONFIG_PM
 323
 324 static int mmpcam_suspend(struct platform_device *pdev, pm_message_t state)
 325 {
 326         struct mmp_camera *cam = mmpcam_find_device(pdev);
 327
 328         if (state.event != PM_EVENT_SUSPEND)
 329                 return 0;
 330         mccic_suspend(&cam->mcam);
 331         return 0;
 332 }
 333
 334 static int mmpcam_resume(struct platform_device *pdev)
 335 {
 336         struct mmp_camera *cam = mmpcam_find_device(pdev);
 337
 338         /*
 339          * Power up unconditionally just in case the core tries to
 340          * touch a register even if nothing was active before; trust
 341          * me, it's better this way.
 342          */
 343         mmpcam_power_up_ctlr(cam);
 344         return mccic_resume(&cam->mcam);
 345 }
 346
 347 #endif
 348
 349
 350 static struct platform_driver mmpcam_driver = {
 351         .probe          = mmpcam_probe,
 352         .remove         = mmpcam_platform_remove,
 353 #ifdef CONFIG_PM
 354         .suspend        = mmpcam_suspend,
 355         .resume         = mmpcam_resume,
 356 #endif
 357         .driver = {
 358                 .name   = "mmp-camera",
 359                 .owner  = THIS_MODULE
 360         }
 361 };
 362
 363
 364 static int __init mmpcam_init_module(void)
 365 {
 366         mutex_init(&mmpcam_devices_lock);
 367         return platform_driver_register(&mmpcam_driver);
 368 }
 369
 370 static void __exit mmpcam_exit_module(void)
 371 {
 372         platform_driver_unregister(&mmpcam_driver);
 373         /*
 374          * platform_driver_unregister() should have emptied the list
 375          */
 376         if (!list_empty(&mmpcam_devices))
 377                 printk(KERN_ERR "mmp_camera leaving devices behind\n");
 378 }
 379
 380 module_init(mmpcam_init_module);
 381 module_exit(mmpcam_exit_module);