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(struct mcam_camera *mcam)
 110 {
 111         struct mmp_camera *cam = mcam_to_cam(mcam);
 112         struct mmp_camera_platform_data *pdata;
 113 /*
 114  * Turn on power and clocks to the controller.
 115  */
 116         iowrite32(0x3f, cam->power_regs + REG_CCIC_DCGCR);
 117         iowrite32(0x3805b, cam->power_regs + REG_CCIC_CRCR);
 118         mdelay(1);
 119 /*
 120  * Provide power to the sensor.
 121  */
 122         mcam_reg_write(mcam, REG_CLKCTRL, 0x60000002);
 123         pdata = cam->pdev->dev.platform_data;
 124         gpio_set_value(pdata->sensor_power_gpio, 1);
 125         mdelay(5);
 126         mcam_reg_clear_bit(mcam, REG_CTRL1, 0x10000000);
 127         gpio_set_value(pdata->sensor_reset_gpio, 0); /* reset is active low */
 128         mdelay(5);
 129         gpio_set_value(pdata->sensor_reset_gpio, 1); /* reset is active low */
 130         mdelay(5);
 131 }
 132
 133 static void mmpcam_power_down(struct mcam_camera *mcam)
 134 {
 135         struct mmp_camera *cam = mcam_to_cam(mcam);
 136         struct mmp_camera_platform_data *pdata;
 137 /*
 138  * Turn off clocks and set reset lines
 139  */
 140         iowrite32(0, cam->power_regs + REG_CCIC_DCGCR);
 141         iowrite32(0, cam->power_regs + REG_CCIC_CRCR);
 142 /*
 143  * Shut down the sensor.
 144  */
 145         pdata = cam->pdev->dev.platform_data;
 146         gpio_set_value(pdata->sensor_power_gpio, 0);
 147         gpio_set_value(pdata->sensor_reset_gpio, 0);
 148 }
 149
 150
 151 static irqreturn_t mmpcam_irq(int irq, void *data)
 152 {
 153         struct mcam_camera *mcam = data;
 154         unsigned int irqs, handled;
 155
 156         spin_lock(&mcam->dev_lock);
 157         irqs = mcam_reg_read(mcam, REG_IRQSTAT);
 158         handled = mccic_irq(mcam, irqs);
 159         spin_unlock(&mcam->dev_lock);
 160         return IRQ_RETVAL(handled);
 161 }
 162
 163
 164 static int mmpcam_probe(struct platform_device *pdev)
 165 {
 166         struct mmp_camera *cam;
 167         struct mcam_camera *mcam;
 168         struct resource *res;
 169         struct mmp_camera_platform_data *pdata;
 170         int ret;
 171
 172         cam = kzalloc(sizeof(*cam), GFP_KERNEL);
 173         if (cam == NULL)
 174                 return -ENOMEM;
 175         cam->pdev = pdev;
 176         INIT_LIST_HEAD(&cam->devlist);
 177
 178         mcam = &cam->mcam;
 179         mcam->platform = MHP_Armada610;
 180         mcam->plat_power_up = mmpcam_power_up;
 181         mcam->plat_power_down = mmpcam_power_down;
 182         mcam->dev = &pdev->dev;
 183         mcam->use_smbus = 0;
 184         mcam->chip_id = V4L2_IDENT_ARMADA610;
 185         mcam->buffer_mode = B_DMA_sg;
 186         spin_lock_init(&mcam->dev_lock);
 187         /*
 188          * Get our I/O memory.
 189          */
 190         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 191         if (res == NULL) {
 192                 dev_err(&pdev->dev, "no iomem resource!\n");
 193                 ret = -ENODEV;
 194                 goto out_free;
 195         }
 196         mcam->regs = ioremap(res->start, resource_size(res));
 197         if (mcam->regs == NULL) {
 198                 dev_err(&pdev->dev, "MMIO ioremap fail\n");
 199                 ret = -ENODEV;
 200                 goto out_free;
 201         }
 202         /*
 203          * Power/clock memory is elsewhere; get it too.  Perhaps this
 204          * should really be managed outside of this driver?
 205          */
 206         res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
 207         if (res == NULL) {
 208                 dev_err(&pdev->dev, "no power resource!\n");
 209                 ret = -ENODEV;
 210                 goto out_unmap1;
 211         }
 212         cam->power_regs = ioremap(res->start, resource_size(res));
 213         if (cam->power_regs == NULL) {
 214                 dev_err(&pdev->dev, "power MMIO ioremap fail\n");
 215                 ret = -ENODEV;
 216                 goto out_unmap1;
 217         }
 218         /*
 219          * Find the i2c adapter.  This assumes, of course, that the
 220          * i2c bus is already up and functioning.
 221          */
 222         pdata = pdev->dev.platform_data;
 223         mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
 224         if (mcam->i2c_adapter == NULL) {
 225                 ret = -ENODEV;
 226                 dev_err(&pdev->dev, "No i2c adapter\n");
 227                 goto out_unmap2;
 228         }
 229         /*
 230          * Sensor GPIO pins.
 231          */
 232         ret = gpio_request(pdata->sensor_power_gpio, "cam-power");
 233         if (ret) {
 234                 dev_err(&pdev->dev, "Can't get sensor power gpio %d",
 235                                 pdata->sensor_power_gpio);
 236                 goto out_unmap2;
 237         }
 238         gpio_direction_output(pdata->sensor_power_gpio, 0);
 239         ret = gpio_request(pdata->sensor_reset_gpio, "cam-reset");
 240         if (ret) {
 241                 dev_err(&pdev->dev, "Can't get sensor reset gpio %d",
 242                                 pdata->sensor_reset_gpio);
 243                 goto out_gpio;
 244         }
 245         gpio_direction_output(pdata->sensor_reset_gpio, 0);
 246         /*
 247          * Power the device up and hand it off to the core.
 248          */
 249         mmpcam_power_up(mcam);
 250         ret = mccic_register(mcam);
 251         if (ret)
 252                 goto out_gpio2;
 253         /*
 254          * Finally, set up our IRQ now that the core is ready to
 255          * deal with it.
 256          */
 257         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 258         if (res == NULL) {
 259                 ret = -ENODEV;
 260                 goto out_unregister;
 261         }
 262         cam->irq = res->start;
 263         ret = request_irq(cam->irq, mmpcam_irq, IRQF_SHARED,
 264                         "mmp-camera", mcam);
 265         if (ret == 0) {
 266                 mmpcam_add_device(cam);
 267                 return 0;
 268         }
 269
 270 out_unregister:
 271         mccic_shutdown(mcam);
 272 out_gpio2:
 273         mmpcam_power_down(mcam);
 274         gpio_free(pdata->sensor_reset_gpio);
 275 out_gpio:
 276         gpio_free(pdata->sensor_power_gpio);
 277 out_unmap2:
 278         iounmap(cam->power_regs);
 279 out_unmap1:
 280         iounmap(mcam->regs);
 281 out_free:
 282         kfree(cam);
 283         return ret;
 284 }
 285
 286
 287 static int mmpcam_remove(struct mmp_camera *cam)
 288 {
 289         struct mcam_camera *mcam = &cam->mcam;
 290         struct mmp_camera_platform_data *pdata;
 291
 292         mmpcam_remove_device(cam);
 293         free_irq(cam->irq, mcam);
 294         mccic_shutdown(mcam);
 295         mmpcam_power_down(mcam);
 296         pdata = cam->pdev->dev.platform_data;
 297         gpio_free(pdata->sensor_reset_gpio);
 298         gpio_free(pdata->sensor_power_gpio);
 299         iounmap(cam->power_regs);
 300         iounmap(mcam->regs);
 301         kfree(cam);
 302         return 0;
 303 }
 304
 305 static int mmpcam_platform_remove(struct platform_device *pdev)
 306 {
 307         struct mmp_camera *cam = mmpcam_find_device(pdev);
 308
 309         if (cam == NULL)
 310                 return -ENODEV;
 311         return mmpcam_remove(cam);
 312 }
 313
 314 /*
 315  * Suspend/resume support.
 316  */
 317 #ifdef CONFIG_PM
 318
 319 static int mmpcam_suspend(struct platform_device *pdev, pm_message_t state)
 320 {
 321         struct mmp_camera *cam = mmpcam_find_device(pdev);
 322
 323         if (state.event != PM_EVENT_SUSPEND)
 324                 return 0;
 325         mccic_suspend(&cam->mcam);
 326         return 0;
 327 }
 328
 329 static int mmpcam_resume(struct platform_device *pdev)
 330 {
 331         struct mmp_camera *cam = mmpcam_find_device(pdev);
 332
 333         /*
 334          * Power up unconditionally just in case the core tries to
 335          * touch a register even if nothing was active before; trust
 336          * me, it's better this way.
 337          */
 338         mmpcam_power_up(&cam->mcam);
 339         return mccic_resume(&cam->mcam);
 340 }
 341
 342 #endif
 343
 344
 345 static struct platform_driver mmpcam_driver = {
 346         .probe          = mmpcam_probe,
 347         .remove         = mmpcam_platform_remove,
 348 #ifdef CONFIG_PM
 349         .suspend        = mmpcam_suspend,
 350         .resume         = mmpcam_resume,
 351 #endif
 352         .driver = {
 353                 .name   = "mmp-camera",
 354                 .owner  = THIS_MODULE
 355         }
 356 };
 357
 358
 359 static int __init mmpcam_init_module(void)
 360 {
 361         mutex_init(&mmpcam_devices_lock);
 362         return platform_driver_register(&mmpcam_driver);
 363 }
 364
 365 static void __exit mmpcam_exit_module(void)
 366 {
 367         platform_driver_unregister(&mmpcam_driver);
 368         /*
 369          * platform_driver_unregister() should have emptied the list
 370          */
 371         if (!list_empty(&mmpcam_devices))
 372                 printk(KERN_ERR "mmp_camera leaving devices behind\n");
 373 }
 374
 375 module_init(mmpcam_init_module);
 376 module_exit(mmpcam_exit_module);