V4L/DVB: V4L2: soc-camera: add a MIPI CSI-2 driver for SH-Mobile platforms

Some SH-Mobile SoCs implement a MIPI CSI-2 controller, that can interface to
several video clients and send data to the CEU or to the Image Signal
Processor.  This patch implements a v4l2-subdevice driver for CSI-2 to be used
within the soc-camera framework, implementing the second subdevice in addition
to the actual video clients.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 361 insertions, 0 deletions

diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
index c627f776c1e9..0f1ac401dedd 100644
--- a/drivers/media/video/Kconfig
+++ b/drivers/media/video/Kconfig
@@ -876,6 +876,12 @@ config VIDEO_PXA27x
         ---help---
           This is a v4l2 driver for the PXA27x Quick Capture Interface
 
+config VIDEO_SH_MOBILE_CSI2
+        tristate "SuperH Mobile MIPI CSI-2 Interface driver"
+        depends on VIDEO_DEV && SOC_CAMERA && HAVE_CLK
+        ---help---
+          This is a v4l2 driver for the SuperH MIPI CSI-2 Interface
+
 config VIDEO_SH_MOBILE_CEU
         tristate "SuperH Mobile CEU Interface driver"
         depends on VIDEO_DEV && SOC_CAMERA && HAS_DMA && HAVE_CLK
diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
index eba259fbf7ef..88478630e854 100644
--- a/drivers/media/video/Makefile
+++ b/drivers/media/video/Makefile
@@ -160,6 +160,7 @@ obj-$(CONFIG_SOC_CAMERA_PLATFORM)	+= soc_camera_platform.o
 obj-$(CONFIG_VIDEO_MX1)                 += mx1_camera.o
 obj-$(CONFIG_VIDEO_MX3)                 += mx3_camera.o
 obj-$(CONFIG_VIDEO_PXA27x)              += pxa_camera.o
+obj-$(CONFIG_VIDEO_SH_MOBILE_CSI2)      += sh_mobile_csi2.o
 obj-$(CONFIG_VIDEO_SH_MOBILE_CEU)       += sh_mobile_ceu_camera.o
 
 obj-$(CONFIG_ARCH_DAVINCI)              += davinci/
diff --git a/drivers/media/video/sh_mobile_csi2.c b/drivers/media/video/sh_mobile_csi2.c
new file mode 100644
index 000000000000..84a646819318
--- /dev/null
+++ b/drivers/media/video/sh_mobile_csi2.c
@@ -0,0 +1,354 @@
+/*
+ * Driver for the SH-Mobile MIPI CSI-2 unit
+ *
+ * Copyright (C) 2010, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/slab.h>
+#include <linux/videodev2.h>
+
+#include <media/sh_mobile_csi2.h>
+#include <media/soc_camera.h>
+#include <media/v4l2-common.h>
+#include <media/v4l2-dev.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-mediabus.h>
+#include <media/v4l2-subdev.h>
+
+#define SH_CSI2_TREF    0x00
+#define SH_CSI2_SRST    0x04
+#define SH_CSI2_PHYCNT  0x08
+#define SH_CSI2_CHKSUM  0x0C
+#define SH_CSI2_VCDT    0x10
+
+struct sh_csi2 {
+        struct v4l2_subdev              subdev;
+        struct list_head                list;
+        struct notifier_block           notifier;
+        unsigned int                    irq;
+        void __iomem                    *base;
+        struct platform_device          *pdev;
+        struct sh_csi2_client_config    *client;
+};
+
+static int sh_csi2_try_fmt(struct v4l2_subdev *sd,
+                           struct v4l2_mbus_framefmt *mf)
+{
+        struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
+        struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
+
+        if (mf->width > 8188)
+                mf->width = 8188;
+        else if (mf->width & 1)
+                mf->width &= ~1;
+
+        switch (pdata->type) {
+        case SH_CSI2C:
+                switch (mf->code) {
+                case V4L2_MBUS_FMT_UYVY8_2X8:           /* YUV422 */
+                case V4L2_MBUS_FMT_YUYV8_1_5X8:         /* YUV420 */
+                case V4L2_MBUS_FMT_GREY8_1X8:           /* RAW8 */
+                case V4L2_MBUS_FMT_SBGGR8_1X8:
+                case V4L2_MBUS_FMT_SGRBG8_1X8:
+                        break;
+                default:
+                        /* All MIPI CSI-2 devices must support one of primary formats */
+                        mf->code = V4L2_MBUS_FMT_YUYV8_2X8;
+                }
+                break;
+        case SH_CSI2I:
+                switch (mf->code) {
+                case V4L2_MBUS_FMT_GREY8_1X8:           /* RAW8 */
+                case V4L2_MBUS_FMT_SBGGR8_1X8:
+                case V4L2_MBUS_FMT_SGRBG8_1X8:
+                case V4L2_MBUS_FMT_SBGGR10_1X10:        /* RAW10 */
+                case V4L2_MBUS_FMT_SBGGR12_1X12:        /* RAW12 */
+                        break;
+                default:
+                        /* All MIPI CSI-2 devices must support one of primary formats */
+                        mf->code = V4L2_MBUS_FMT_SBGGR8_1X8;
+                }
+                break;
+        }
+
+        return 0;
+}
+
+/*
+ * We have done our best in try_fmt to try and tell the sensor, which formats
+ * we support. If now the configuration is unsuitable for us we can only
+ * error out.
+ */
+static int sh_csi2_s_fmt(struct v4l2_subdev *sd,
+                         struct v4l2_mbus_framefmt *mf)
+{
+        struct sh_csi2 *priv = container_of(sd, struct sh_csi2, subdev);
+        u32 tmp = (priv->client->channel & 3) << 8;
+
+        dev_dbg(sd->v4l2_dev->dev, "%s(%u)\n", __func__, mf->code);
+        if (mf->width > 8188 || mf->width & 1)
+                return -EINVAL;
+
+        switch (mf->code) {
+        case V4L2_MBUS_FMT_UYVY8_2X8:
+                tmp |= 0x1e;    /* YUV422 8 bit */
+                break;
+        case V4L2_MBUS_FMT_YUYV8_1_5X8:
+                tmp |= 0x18;    /* YUV420 8 bit */
+                break;
+        case V4L2_MBUS_FMT_RGB555_2X8_PADHI_BE:
+                tmp |= 0x21;    /* RGB555 */
+                break;
+        case V4L2_MBUS_FMT_RGB565_2X8_BE:
+                tmp |= 0x22;    /* RGB565 */
+                break;
+        case V4L2_MBUS_FMT_GREY8_1X8:
+        case V4L2_MBUS_FMT_SBGGR8_1X8:
+        case V4L2_MBUS_FMT_SGRBG8_1X8:
+                tmp |= 0x2a;    /* RAW8 */
+                break;
+        default:
+                return -EINVAL;
+        }
+
+        iowrite32(tmp, priv->base + SH_CSI2_VCDT);
+
+        return 0;
+}
+
+static struct v4l2_subdev_video_ops sh_csi2_subdev_video_ops = {
+        .s_mbus_fmt     = sh_csi2_s_fmt,
+        .try_mbus_fmt   = sh_csi2_try_fmt,
+};
+
+static struct v4l2_subdev_core_ops sh_csi2_subdev_core_ops;
+
+static struct v4l2_subdev_ops sh_csi2_subdev_ops = {
+        .core   = &sh_csi2_subdev_core_ops,
+        .video  = &sh_csi2_subdev_video_ops,
+};
+
+static void sh_csi2_hwinit(struct sh_csi2 *priv)
+{
+        struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
+        __u32 tmp = 0x10; /* Enable MIPI CSI clock lane */
+
+        /* Reflect registers immediately */
+        iowrite32(0x00000001, priv->base + SH_CSI2_TREF);
+        /* reset CSI2 harware */
+        iowrite32(0x00000001, priv->base + SH_CSI2_SRST);
+        udelay(5);
+        iowrite32(0x00000000, priv->base + SH_CSI2_SRST);
+
+        if (priv->client->lanes & 3)
+                tmp |= priv->client->lanes & 3;
+        else
+                /* Default - both lanes */
+                tmp |= 3;
+
+        if (priv->client->phy == SH_CSI2_PHY_MAIN)
+                tmp |= 0x8000;
+
+        iowrite32(tmp, priv->base + SH_CSI2_PHYCNT);
+
+        tmp = 0;
+        if (pdata->flags & SH_CSI2_ECC)
+                tmp |= 2;
+        if (pdata->flags & SH_CSI2_CRC)
+                tmp |= 1;
+        iowrite32(tmp, priv->base + SH_CSI2_CHKSUM);
+}
+
+static int sh_csi2_set_bus_param(struct soc_camera_device *icd,
+                                 unsigned long flags)
+{
+        return 0;
+}
+
+static unsigned long sh_csi2_query_bus_param(struct soc_camera_device *icd)
+{
+        struct soc_camera_link *icl = to_soc_camera_link(icd);
+        const unsigned long flags = SOCAM_PCLK_SAMPLE_RISING |
+                SOCAM_HSYNC_ACTIVE_HIGH | SOCAM_VSYNC_ACTIVE_HIGH |
+                SOCAM_MASTER | SOCAM_DATAWIDTH_8 | SOCAM_DATA_ACTIVE_HIGH;
+
+        return soc_camera_apply_sensor_flags(icl, flags);
+}
+
+static int sh_csi2_notify(struct notifier_block *nb,
+                          unsigned long action, void *data)
+{
+        struct device *dev = data;
+        struct soc_camera_device *icd = to_soc_camera_dev(dev);
+        struct v4l2_device *v4l2_dev = dev_get_drvdata(dev->parent);
+        struct sh_csi2 *priv =
+                container_of(nb, struct sh_csi2, notifier);
+        struct sh_csi2_pdata *pdata = priv->pdev->dev.platform_data;
+        int ret, i;
+
+        for (i = 0; i < pdata->num_clients; i++)
+                if (&pdata->clients[i].pdev->dev == icd->pdev)
+                        break;
+
+        dev_dbg(dev, "%s(%p): action = %lu, found #%d\n", __func__, dev, action, i);
+
+        if (i == pdata->num_clients)
+                return NOTIFY_DONE;
+
+        switch (action) {
+        case BUS_NOTIFY_BOUND_DRIVER:
+                snprintf(priv->subdev.name, V4L2_SUBDEV_NAME_SIZE, "%s%s",
+                         dev_name(v4l2_dev->dev), ".mipi-csi");
+                ret = v4l2_device_register_subdev(v4l2_dev, &priv->subdev);
+                dev_dbg(dev, "%s(%p): ret(register_subdev) = %d\n", __func__, priv, ret);
+                if (ret < 0)
+                        return NOTIFY_DONE;
+
+                priv->client = pdata->clients + i;
+
+                icd->ops->set_bus_param         = sh_csi2_set_bus_param;
+                icd->ops->query_bus_param       = sh_csi2_query_bus_param;
+
+                pm_runtime_get_sync(v4l2_get_subdevdata(&priv->subdev));
+
+                sh_csi2_hwinit(priv);
+                break;
+        case BUS_NOTIFY_UNBIND_DRIVER:
+                priv->client = NULL;
+
+                /* Driver is about to be unbound */
+                icd->ops->set_bus_param         = NULL;
+                icd->ops->query_bus_param       = NULL;
+
+                v4l2_device_unregister_subdev(&priv->subdev);
+
+                pm_runtime_put(v4l2_get_subdevdata(&priv->subdev));
+                break;
+        }
+
+        return NOTIFY_OK;
+}
+
+static __devinit int sh_csi2_probe(struct platform_device *pdev)
+{
+        struct resource *res;
+        unsigned int irq;
+        int ret;
+        struct sh_csi2 *priv;
+        /* Platform data specify the PHY, lanes, ECC, CRC */
+        struct sh_csi2_pdata *pdata = pdev->dev.platform_data;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        /* Interrupt unused so far */
+        irq = platform_get_irq(pdev, 0);
+
+        if (!res || (int)irq <= 0 || !pdata) {
+                dev_err(&pdev->dev, "Not enough CSI2 platform resources.\n");
+                return -ENODEV;
+        }
+
+        /* TODO: Add support for CSI2I. Careful: different register layout! */
+        if (pdata->type != SH_CSI2C) {
+                dev_err(&pdev->dev, "Only CSI2C supported ATM.\n");
+                return -EINVAL;
+        }
+
+        priv = kzalloc(sizeof(struct sh_csi2), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+
+        priv->irq = irq;
+        priv->notifier.notifier_call = sh_csi2_notify;
+
+        /* We MUST attach after the MIPI sensor */
+        ret = bus_register_notifier(&soc_camera_bus_type, &priv->notifier);
+        if (ret < 0) {
+                dev_err(&pdev->dev, "CSI2 cannot register notifier\n");
+                goto ernotify;
+        }
+
+        if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
+                dev_err(&pdev->dev, "CSI2 register region already claimed\n");
+                ret = -EBUSY;
+                goto ereqreg;
+        }
+
+        priv->base = ioremap(res->start, resource_size(res));
+        if (!priv->base) {
+                ret = -ENXIO;
+                dev_err(&pdev->dev, "Unable to ioremap CSI2 registers.\n");
+                goto eremap;
+        }
+
+        priv->pdev = pdev;
+
+        v4l2_subdev_init(&priv->subdev, &sh_csi2_subdev_ops);
+        v4l2_set_subdevdata(&priv->subdev, &pdev->dev);
+
+        platform_set_drvdata(pdev, priv);
+
+        pm_runtime_enable(&pdev->dev);
+
+        dev_dbg(&pdev->dev, "CSI2 probed.\n");
+
+        return 0;
+
+eremap:
+        release_mem_region(res->start, resource_size(res));
+ereqreg:
+        bus_unregister_notifier(&soc_camera_bus_type, &priv->notifier);
+ernotify:
+        kfree(priv);
+
+        return ret;
+}
+
+static __devexit int sh_csi2_remove(struct platform_device *pdev)
+{
+        struct sh_csi2 *priv = platform_get_drvdata(pdev);
+        struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+        bus_unregister_notifier(&soc_camera_bus_type, &priv->notifier);
+        pm_runtime_disable(&pdev->dev);
+        iounmap(priv->base);
+        release_mem_region(res->start, resource_size(res));
+        platform_set_drvdata(pdev, NULL);
+        kfree(priv);
+
+        return 0;
+}
+
+static struct platform_driver __refdata sh_csi2_pdrv = {
+        .remove  = __devexit_p(sh_csi2_remove),
+        .driver  = {
+                .name   = "sh-mobile-csi2",
+                .owner  = THIS_MODULE,
+        },
+};
+
+static int __init sh_csi2_init(void)
+{
+        return platform_driver_probe(&sh_csi2_pdrv, sh_csi2_probe);
+}
+
+static void __exit sh_csi2_exit(void)
+{
+        platform_driver_unregister(&sh_csi2_pdrv);
+}
+
+module_init(sh_csi2_init);
+module_exit(sh_csi2_exit);
+
+MODULE_DESCRIPTION("SH-Mobile MIPI CSI-2 driver");
+MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:sh-mobile-csi2");