drivers/media/platform/marvell/mmp-driver.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Support for the camera device found on Marvell MMP processors; known
   4  * to work with the Armada 610 as used in the OLPC 1.75 system.
   5  *
   6  * Copyright 2011 Jonathan Corbet <corbet@lwn.net>
   7  * Copyright 2018 Lubomir Rintel <lkundrak@v3.sk>
   8  */
   9
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/slab.h>
  16 #include <linux/videodev2.h>
  17 #include <media/v4l2-device.h>
  18 #include <linux/platform_data/media/mmp-camera.h>
  19 #include <linux/device.h>
  20 #include <linux/of.h>
  21 #include <linux/of_platform.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/pm_runtime.h>
  24 #include <linux/io.h>
  25 #include <linux/list.h>
  26 #include <linux/pm.h>
  27 #include <linux/clk.h>
  28
  29 #include "mcam-core.h"
  30
  31 MODULE_ALIAS("platform:mmp-camera");
  32 MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
  33 MODULE_DESCRIPTION("Support for the camera device found on Marvell MMP processors");
  34 MODULE_LICENSE("GPL");
  35
  36 static char *mcam_clks[] = {"axi", "func", "phy"};
  37
  38 struct mmp_camera {
  39         struct platform_device *pdev;
  40         struct mcam_camera mcam;
  41         struct list_head devlist;
  42         struct clk *mipi_clk;
  43         int irq;
  44 };
  45
  46 static inline struct mmp_camera *mcam_to_cam(struct mcam_camera *mcam)
  47 {
  48         return container_of(mcam, struct mmp_camera, mcam);
  49 }
  50
  51 /*
  52  * calc the dphy register values
  53  * There are three dphy registers being used.
  54  * dphy[0] - CSI2_DPHY3
  55  * dphy[1] - CSI2_DPHY5
  56  * dphy[2] - CSI2_DPHY6
  57  * CSI2_DPHY3 and CSI2_DPHY6 can be set with a default value
  58  * or be calculated dynamically
  59  */
  60 static void mmpcam_calc_dphy(struct mcam_camera *mcam)
  61 {
  62         struct mmp_camera *cam = mcam_to_cam(mcam);
  63         struct mmp_camera_platform_data *pdata = cam->pdev->dev.platform_data;
  64         struct device *dev = &cam->pdev->dev;
  65         unsigned long tx_clk_esc;
  66
  67         /*
  68          * If CSI2_DPHY3 is calculated dynamically,
  69          * pdata->lane_clk should be already set
  70          * either in the board driver statically
  71          * or in the sensor driver dynamically.
  72          */
  73         /*
  74          * dphy[0] - CSI2_DPHY3:
  75          *  bit 0 ~ bit 7: HS Term Enable.
  76          *   defines the time that the DPHY
  77          *   wait before enabling the data
  78          *   lane termination after detecting
  79          *   that the sensor has driven the data
  80          *   lanes to the LP00 bridge state.
  81          *   The value is calculated by:
  82          *   (Max T(D_TERM_EN)/Period(DDR)) - 1
  83          *  bit 8 ~ bit 15: HS_SETTLE
  84          *   Time interval during which the HS
  85          *   receiver shall ignore any Data Lane
  86          *   HS transitions.
  87          *   The value has been calibrated on
  88          *   different boards. It seems to work well.
  89          *
  90          *  More detail please refer
  91          *  MIPI Alliance Spectification for D-PHY
  92          *  document for explanation of HS-SETTLE
  93          *  and D-TERM-EN.
  94          */
  95         switch (pdata->dphy3_algo) {
  96         case DPHY3_ALGO_PXA910:
  97                 /*
  98                  * Calculate CSI2_DPHY3 algo for PXA910
  99                  */
 100                 pdata->dphy[0] =
 101                         (((1 + (pdata->lane_clk * 80) / 1000) & 0xff) << 8)
 102                         | (1 + pdata->lane_clk * 35 / 1000);
 103                 break;
 104         case DPHY3_ALGO_PXA2128:
 105                 /*
 106                  * Calculate CSI2_DPHY3 algo for PXA2128
 107                  */
 108                 pdata->dphy[0] =
 109                         (((2 + (pdata->lane_clk * 110) / 1000) & 0xff) << 8)
 110                         | (1 + pdata->lane_clk * 35 / 1000);
 111                 break;
 112         default:
 113                 /*
 114                  * Use default CSI2_DPHY3 value for PXA688/PXA988
 115                  */
 116                 dev_dbg(dev, "camera: use the default CSI2_DPHY3 value\n");
 117         }
 118
 119         /*
 120          * mipi_clk will never be changed, it is a fixed value on MMP
 121          */
 122         if (IS_ERR(cam->mipi_clk))
 123                 return;
 124
 125         /* get the escape clk, this is hard coded */
 126         clk_prepare_enable(cam->mipi_clk);
 127         tx_clk_esc = (clk_get_rate(cam->mipi_clk) / 1000000) / 12;
 128         clk_disable_unprepare(cam->mipi_clk);
 129         /*
 130          * dphy[2] - CSI2_DPHY6:
 131          * bit 0 ~ bit 7: CK Term Enable
 132          *  Time for the Clock Lane receiver to enable the HS line
 133          *  termination. The value is calculated similarly with
 134          *  HS Term Enable
 135          * bit 8 ~ bit 15: CK Settle
 136          *  Time interval during which the HS receiver shall ignore
 137          *  any Clock Lane HS transitions.
 138          *  The value is calibrated on the boards.
 139          */
 140         pdata->dphy[2] =
 141                 ((((534 * tx_clk_esc) / 2000 - 1) & 0xff) << 8)
 142                 | (((38 * tx_clk_esc) / 1000 - 1) & 0xff);
 143
 144         dev_dbg(dev, "camera: DPHY sets: dphy3=0x%x, dphy5=0x%x, dphy6=0x%x\n",
 145                 pdata->dphy[0], pdata->dphy[1], pdata->dphy[2]);
 146 }
 147
 148 static irqreturn_t mmpcam_irq(int irq, void *data)
 149 {
 150         struct mcam_camera *mcam = data;
 151         unsigned int irqs, handled;
 152
 153         spin_lock(&mcam->dev_lock);
 154         irqs = mcam_reg_read(mcam, REG_IRQSTAT);
 155         handled = mccic_irq(mcam, irqs);
 156         spin_unlock(&mcam->dev_lock);
 157         return IRQ_RETVAL(handled);
 158 }
 159
 160 static void mcam_init_clk(struct mcam_camera *mcam)
 161 {
 162         unsigned int i;
 163
 164         for (i = 0; i < NR_MCAM_CLK; i++) {
 165                 if (mcam_clks[i] != NULL) {
 166                         /* Some clks are not necessary on some boards
 167                          * We still try to run even it fails getting clk
 168                          */
 169                         mcam->clk[i] = devm_clk_get(mcam->dev, mcam_clks[i]);
 170                         if (IS_ERR(mcam->clk[i]))
 171                                 dev_warn(mcam->dev, "Could not get clk: %s\n",
 172                                                 mcam_clks[i]);
 173                 }
 174         }
 175 }
 176
 177 static int mmpcam_probe(struct platform_device *pdev)
 178 {
 179         struct mmp_camera *cam;
 180         struct mcam_camera *mcam;
 181         struct resource *res;
 182         struct fwnode_handle *ep;
 183         struct mmp_camera_platform_data *pdata;
 184         struct v4l2_async_connection *asd;
 185         int ret;
 186
 187         cam = devm_kzalloc(&pdev->dev, sizeof(*cam), GFP_KERNEL);
 188         if (cam == NULL)
 189                 return -ENOMEM;
 190         platform_set_drvdata(pdev, cam);
 191         cam->pdev = pdev;
 192         INIT_LIST_HEAD(&cam->devlist);
 193
 194         mcam = &cam->mcam;
 195         mcam->calc_dphy = mmpcam_calc_dphy;
 196         mcam->dev = &pdev->dev;
 197         pdata = pdev->dev.platform_data;
 198         if (pdata) {
 199                 mcam->mclk_src = pdata->mclk_src;
 200                 mcam->mclk_div = pdata->mclk_div;
 201                 mcam->bus_type = pdata->bus_type;
 202                 mcam->dphy = pdata->dphy;
 203                 mcam->lane = pdata->lane;
 204         } else {
 205                 /*
 206                  * These are values that used to be hardcoded in mcam-core and
 207                  * work well on a OLPC XO 1.75 with a parallel bus sensor.
 208                  * If it turns out other setups make sense, the values should
 209                  * be obtained from the device tree.
 210                  */
 211                 mcam->mclk_src = 3;
 212                 mcam->mclk_div = 2;
 213         }
 214         if (mcam->bus_type == V4L2_MBUS_CSI2_DPHY) {
 215                 cam->mipi_clk = devm_clk_get(mcam->dev, "mipi");
 216                 if ((IS_ERR(cam->mipi_clk) && mcam->dphy[2] == 0))
 217                         return PTR_ERR(cam->mipi_clk);
 218         }
 219         mcam->mipi_enabled = false;
 220         mcam->chip_id = MCAM_ARMADA610;
 221         mcam->buffer_mode = B_DMA_sg;
 222         strscpy(mcam->bus_info, "platform:mmp-camera", sizeof(mcam->bus_info));
 223         spin_lock_init(&mcam->dev_lock);
 224         /*
 225          * Get our I/O memory.
 226          */
 227         mcam->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 228         if (IS_ERR(mcam->regs))
 229                 return PTR_ERR(mcam->regs);
 230         mcam->regs_size = resource_size(res);
 231
 232         mcam_init_clk(mcam);
 233
 234         /*
 235          * Create a match of the sensor against its OF node.
 236          */
 237         ep = fwnode_graph_get_next_endpoint(of_fwnode_handle(pdev->dev.of_node),
 238                                             NULL);
 239         if (!ep)
 240                 return -ENODEV;
 241
 242         v4l2_async_nf_init(&mcam->notifier, &mcam->v4l2_dev);
 243
 244         asd = v4l2_async_nf_add_fwnode_remote(&mcam->notifier, ep,
 245                                               struct v4l2_async_connection);
 246         fwnode_handle_put(ep);
 247         if (IS_ERR(asd)) {
 248                 ret = PTR_ERR(asd);
 249                 goto out;
 250         }
 251
 252         /*
 253          * Register the device with the core.
 254          */
 255         ret = mccic_register(mcam);
 256         if (ret)
 257                 goto out;
 258
 259         /*
 260          * Add OF clock provider.
 261          */
 262         ret = of_clk_add_provider(pdev->dev.of_node, of_clk_src_simple_get,
 263                                                                 mcam->mclk);
 264         if (ret) {
 265                 dev_err(&pdev->dev, "can't add DT clock provider\n");
 266                 goto out;
 267         }
 268
 269         /*
 270          * Finally, set up our IRQ now that the core is ready to
 271          * deal with it.
 272          */
 273         ret = platform_get_irq(pdev, 0);
 274         if (ret < 0)
 275                 goto out;
 276         cam->irq = ret;
 277         ret = devm_request_irq(&pdev->dev, cam->irq, mmpcam_irq, IRQF_SHARED,
 278                                         "mmp-camera", mcam);
 279         if (ret)
 280                 goto out;
 281
 282         pm_runtime_enable(&pdev->dev);
 283         return 0;
 284 out:
 285         mccic_shutdown(mcam);
 286
 287         return ret;
 288 }
 289
 290 static void mmpcam_remove(struct platform_device *pdev)
 291 {
 292         struct mmp_camera *cam = platform_get_drvdata(pdev);
 293         struct mcam_camera *mcam = &cam->mcam;
 294
 295         mccic_shutdown(mcam);
 296         pm_runtime_force_suspend(mcam->dev);
 297 }
 298
 299 /*
 300  * Suspend/resume support.
 301  */
 302
 303 static int __maybe_unused mmpcam_runtime_resume(struct device *dev)
 304 {
 305         struct mmp_camera *cam = dev_get_drvdata(dev);
 306         struct mcam_camera *mcam = &cam->mcam;
 307         unsigned int i;
 308
 309         for (i = 0; i < NR_MCAM_CLK; i++) {
 310                 if (!IS_ERR(mcam->clk[i]))
 311                         clk_prepare_enable(mcam->clk[i]);
 312         }
 313
 314         return 0;
 315 }
 316
 317 static int __maybe_unused mmpcam_runtime_suspend(struct device *dev)
 318 {
 319         struct mmp_camera *cam = dev_get_drvdata(dev);
 320         struct mcam_camera *mcam = &cam->mcam;
 321         int i;
 322
 323         for (i = NR_MCAM_CLK - 1; i >= 0; i--) {
 324                 if (!IS_ERR(mcam->clk[i]))
 325                         clk_disable_unprepare(mcam->clk[i]);
 326         }
 327
 328         return 0;
 329 }
 330
 331 static int __maybe_unused mmpcam_suspend(struct device *dev)
 332 {
 333         struct mmp_camera *cam = dev_get_drvdata(dev);
 334
 335         if (!pm_runtime_suspended(dev))
 336                 mccic_suspend(&cam->mcam);
 337         return 0;
 338 }
 339
 340 static int __maybe_unused mmpcam_resume(struct device *dev)
 341 {
 342         struct mmp_camera *cam = dev_get_drvdata(dev);
 343
 344         if (!pm_runtime_suspended(dev))
 345                 return mccic_resume(&cam->mcam);
 346         return 0;
 347 }
 348
 349 static const struct dev_pm_ops mmpcam_pm_ops = {
 350         SET_RUNTIME_PM_OPS(mmpcam_runtime_suspend, mmpcam_runtime_resume, NULL)
 351         SET_SYSTEM_SLEEP_PM_OPS(mmpcam_suspend, mmpcam_resume)
 352 };
 353
 354 static const struct of_device_id mmpcam_of_match[] = {
 355         { .compatible = "marvell,mmp2-ccic", },
 356         {},
 357 };
 358 MODULE_DEVICE_TABLE(of, mmpcam_of_match);
 359
 360 static struct platform_driver mmpcam_driver = {
 361         .probe          = mmpcam_probe,
 362         .remove_new     = mmpcam_remove,
 363         .driver = {
 364                 .name   = "mmp-camera",
 365                 .of_match_table = mmpcam_of_match,
 366                 .pm = &mmpcam_pm_ops,
 367         }
 368 };
 369
 370 module_platform_driver(mmpcam_driver);