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