Add a v4l2 subdevice driver for the Synopsys DesignWare MIPI CSI-2 host
controller on i.MX6. Here its output is connected to the CSI2IPU gasket,
which distributes the time division multiplexed virtual channels to the
four IPU CSI inputs, directly or through video bus multiplexers.

Signed-off-by: Philipp Zabel <p.za...@pengutronix.de>
---
Changes since v1:
 - Call mipi_csi2_prepare_stream from mipi_csi2_s_stream and propagate
   s_stream to MIPI CSI-2 transmitter in the correct order.
---
 .../devicetree/bindings/media/fsl-imx-capture.txt  |  67 ++
 drivers/media/platform/imx/Kconfig                 |   7 +
 drivers/media/platform/imx/Makefile                |   1 +
 drivers/media/platform/imx/imx-mipi-csi2.c         | 697 +++++++++++++++++++++
 4 files changed, 772 insertions(+)
 create mode 100644 drivers/media/platform/imx/imx-mipi-csi2.c

diff --git a/Documentation/devicetree/bindings/media/fsl-imx-capture.txt 
b/Documentation/devicetree/bindings/media/fsl-imx-capture.txt
index 5805331..b5ef101 100644
--- a/Documentation/devicetree/bindings/media/fsl-imx-capture.txt
+++ b/Documentation/devicetree/bindings/media/fsl-imx-capture.txt
@@ -23,3 +23,70 @@ capture-subsystem {
         compatible = "fsl,imx-capture-subsystem";
         ports = <&ipu1_csi0>, <&ipu1_csi1>, <&ipu2_csi0>, <&ipu2_csi1>;
 };
+
+i.MX MIPI CSI-2 Host Controller
+===============================
+
+The i.MX6 contains an implementation of a Synopsys DesignWare MIPI CSI-2 host
+controller combined with a CSI2IPU gasket that distributes the virtual channels
+to up to four IPUv3 CSIs.
+
+Required properties:
+- compatible: should be "fsl,imx6q-mipi-csi2", "snps,dw-mipi-csi2"
+- reg: should be register base and length as documented in the SoC
+  reference manual
+- clocks: should contain the pclk, cfg, ref, and pixel clocks, in the
+  order determined by the clock-names property.
+- clock-names: should be "pclk", "cfg", "ref", "pixel"
+- address-cells: should be 1
+- size-cells: should be 0
+- port@*: five port nodes using of_graph bindings, one input port and four
+  output ports corresponding to the virtual channels.
+
+Example:
+
+mipi_csi: mipi@021dc000 {
+       compatible = "fsl,imx6q-mipi-csi2", "snps,dw-mipi-csi2";
+       reg = <0x021dc000 0x4000>;
+       clocks = <&clks IMX6QDL_CLK_HSI_TX>, <&clks IMX6QDL_CLK_HSI_TX>,
+                <&clks IMX6QDL_CLK_HSI_TX>, <&clks IMX6QDL_CLK_EIM_PODF>;
+       clock-names = "pclk", "cfg", "ref", "pixel";
+       #address-cells = <1>;
+       #size-cells = <0>;
+
+       port@0 {
+               reg = <0>;
+       };
+
+       port@1 {
+               reg = <1>;
+
+               vc0: endpoint {
+                       remote-endpoint = <&csi0_in>;
+               };
+       };
+
+       port@2 {
+               reg = <2>;
+
+               vc1: endpoint {
+                       remote-endpoint = <&csi1_in>;
+               };
+       };
+
+       port@3 {
+               reg = <3>;
+
+               vc2: endpoint {
+                       remote-endpoint = <&csi2_in>;
+               };
+       };
+
+       port@4 {
+               reg = <4>;
+
+               vc3: endpoint {
+                       remote-endpoint = <&csi3_in>;
+               };
+       };
+};
diff --git a/drivers/media/platform/imx/Kconfig 
b/drivers/media/platform/imx/Kconfig
index 69e8648..db04e64 100644
--- a/drivers/media/platform/imx/Kconfig
+++ b/drivers/media/platform/imx/Kconfig
@@ -6,6 +6,13 @@ config MEDIA_IMX
          This driver provides a SoC wide media controller device that all
          multimedia components in i.MX5 and i.MX6 SoCs can register with.
 
+config MEDIA_IMX_MIPI_CSI2
+       tristate "i.MX MIPI CSI-2 Host Controller"
+       depends on VIDEO_V4L2_SUBDEV_API
+       help
+         This driver provides support for the MIPI CSI-2 Host Controller that
+         is connected to the IPU CSI input multiplexers on i.MX6 SoCs.
+
 config VIDEO_IMX_IPU_COMMON
        tristate
 
diff --git a/drivers/media/platform/imx/Makefile 
b/drivers/media/platform/imx/Makefile
index 919eaa1..22d86fd 100644
--- a/drivers/media/platform/imx/Makefile
+++ b/drivers/media/platform/imx/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_MEDIA_IMX)                        += imx-media.o
+obj-$(CONFIG_MEDIA_IMX_MIPI_CSI2)      += imx-mipi-csi2.o
 obj-$(CONFIG_VIDEO_IMX_IPU_COMMON)     += imx-ipu.o
 obj-$(CONFIG_VIDEO_IMX_IPU_CAPTURE)    += imx-ipu-capture.o
 obj-$(CONFIG_VIDEO_IMX_IPU_CSI)                += imx-ipuv3-csi.o
diff --git a/drivers/media/platform/imx/imx-mipi-csi2.c 
b/drivers/media/platform/imx/imx-mipi-csi2.c
new file mode 100644
index 0000000..7b289cc
--- /dev/null
+++ b/drivers/media/platform/imx/imx-mipi-csi2.c
@@ -0,0 +1,697 @@
+/*
+ * i.MX MIPI CSI-2 Host Controller driver
+ *
+ * Copyright (C) 2016, Pengutronix, Philipp Zabel <ker...@pengutronix.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/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-of.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#define MIPI_CSI2_VERSION      0x00
+#define MIPI_CSI2_N_LANES      0x04
+#define MIPI_CSI2_PHY_SHUTDOWNZ        0x08
+#define MIPI_CSI2_DPHY_RSTZ    0x0c
+#define MIPI_CSI2_CSI2_RESETN  0x10
+#define MIPI_CSI2_PHY_STATE    0x14
+#define MIPI_CSI2_DATA_IDS_1   0x18
+#define MIPI_CSI2_DATA_IDS_2   0x1c
+#define MIPI_CSI2_ERR1         0x20
+#define MIPI_CSI2_ERR2         0x24
+#define MIPI_CSI2_MASK1                0x28
+#define MIPI_CSI2_MASK2                0x2c
+#define MIPI_CSI2_PHY_TST_CTRL0        0x30
+#define MIPI_CSI2_PHY_TST_CTRL1        0x34
+
+#define CSI2IPU_SW_RST         0xf00
+
+#define PHY_RXULPSESC_0                BIT(0)
+#define PHY_RXULPSESC_1                BIT(1)
+#define PHY_RXULPSESC_2                BIT(2)
+#define PHY_RXULPSESC_3                BIT(3)
+#define PHY_STOPSTATEDATA_0    BIT(4)
+#define PHY_STOPSTATEDATA_1    BIT(5)
+#define PHY_STOPSTATEDATA_2    BIT(6)
+#define PHY_STOPSTATEDATA_3    BIT(7)
+#define PHY_RXCLKACTIVEHS      BIT(8)
+#define PHY_RXULPSCLKNOT       BIT(9)
+#define PHY_STOPSTATECLK       BIT(10)
+#define PHY_BYPASS_2ECC_TST    BIT(11)
+
+#define PHY_TESTCLR            BIT(0)
+#define PHY_TESTCLK            BIT(1)
+
+#define PHY_TESTEN             BIT(16)
+
+#define MIPI_CSI2_VERSION_IMX6 0x3130302a
+
+#define CSI2IPU_RGB444_FM      BIT(3)
+#define CSI2IPU_YUV422_8BIT_FM BIT(2)
+#define CSI2IPU_CLK_SEL                BIT(1)
+
+#define MIPI_CSI2_PADS 5
+
+struct mipi_csi2 {
+       struct v4l2_subdev subdev;
+       struct media_pad pads[MIPI_CSI2_PADS];
+       struct v4l2_mbus_framefmt format;
+       struct v4l2_fract timeperframe;
+       struct device *dev;
+       spinlock_t lock;
+
+       struct clk *pclk;
+       struct clk *cfg_clk;
+       struct clk *ref_clk;
+       struct clk *pixel_clk;
+       void __iomem *regs;
+
+       int max_lanes;
+       int lanes;
+       bool enabled;
+       bool streaming;
+};
+
+struct dphy_pll_testdin_map {
+       u16 max_mbps;
+       u16 testdin;
+};
+
+/* The table is based on 27MHz DPHY pll reference clock. */
+static const struct dphy_pll_testdin_map dptdin_map[] = {
+       { 90, 0x00}, {100, 0x20}, {110, 0x40}, {125, 0x02},
+       {140, 0x22}, {150, 0x42}, {160, 0x04}, {180, 0x24},
+       {200, 0x44}, {210, 0x06}, {240, 0x26}, {250, 0x46},
+       {270, 0x08}, {300, 0x28}, {330, 0x48}, {360, 0x2a},
+       {400, 0x4a}, {450, 0x0c}, {500, 0x2c}, {550, 0x0e},
+       {600, 0x2e}, {650, 0x10}, {700, 0x30}, {750, 0x12},
+       {800, 0x32}, {850, 0x14}, {900, 0x34}, {950, 0x54},
+       {1000, 0x74}
+};
+
+static int max_mbps_to_testdin(unsigned int max_mbps)
+{
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(dptdin_map); i++)
+               if (dptdin_map[i].max_mbps == max_mbps)
+                       return dptdin_map[i].testdin;
+
+       return -EINVAL;
+}
+
+static void mipi_csi2_dphy_write(struct mipi_csi2 *csi2, u8 addr, u8 data)
+{
+       /* Clear PHY test interface */
+       writel(PHY_TESTCLR, csi2->regs + MIPI_CSI2_PHY_TST_CTRL0);
+       writel(0x00000, csi2->regs + MIPI_CSI2_PHY_TST_CTRL1);
+       writel(0, csi2->regs + MIPI_CSI2_PHY_TST_CTRL0);
+
+       /* Raise test interface strobe signal */
+       writel(PHY_TESTCLK, csi2->regs + MIPI_CSI2_PHY_TST_CTRL0);
+
+       /* Configure address write on falling edge and lower strobe signal */
+       writel(PHY_TESTEN | addr, csi2->regs + MIPI_CSI2_PHY_TST_CTRL1);
+       writel(0, csi2->regs + MIPI_CSI2_PHY_TST_CTRL0);
+
+       /* Configure data write on rising edge and raise strobe signal */
+       writel(data, csi2->regs + MIPI_CSI2_PHY_TST_CTRL1);
+       writel(PHY_TESTCLK, csi2->regs + MIPI_CSI2_PHY_TST_CTRL0);
+
+       /* Clear strobe signal */
+       writel(0, csi2->regs + MIPI_CSI2_PHY_TST_CTRL0);
+}
+
+static int mipi_csi2_reset(struct mipi_csi2 *csi2)
+{
+       const u8 addr = 0x44;
+       u8 data = max_mbps_to_testdin(850);
+
+       /* Assert CSI-2 Host Controller and D-PHY resets */
+       writel(0, csi2->regs + MIPI_CSI2_PHY_SHUTDOWNZ);
+       writel(0, csi2->regs + MIPI_CSI2_DPHY_RSTZ);
+       writel(0, csi2->regs + MIPI_CSI2_CSI2_RESETN);
+
+       mipi_csi2_dphy_write(csi2, addr, data);
+
+       /* Deassert resets */
+       writel(1, csi2->regs + MIPI_CSI2_PHY_SHUTDOWNZ);
+       writel(1, csi2->regs + MIPI_CSI2_DPHY_RSTZ);
+       writel(1, csi2->regs + MIPI_CSI2_CSI2_RESETN);
+
+       return 0;
+}
+
+static int mipi_csi2_get_fmt(struct v4l2_subdev *sd,
+                            struct v4l2_subdev_pad_config *cfg,
+                            struct v4l2_subdev_format *sdformat)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+
+       dev_dbg(csi2->dev, "%s\n", __func__);
+
+       if (sdformat->pad > 4)
+               return -EINVAL;
+
+       sdformat->format = csi2->format;
+
+       return 0;
+}
+
+static unsigned int mipi_csi2_format_bpp(u32 mbus_code)
+{
+       switch (mbus_code) {
+       case MEDIA_BUS_FMT_RGB888_1X24:
+               return 24;
+       case MEDIA_BUS_FMT_UYVY8_1X16:
+       case MEDIA_BUS_FMT_YUYV8_1X16:
+               return 16;
+       default:
+               return 0;
+       }
+}
+
+static unsigned int mipi_csi2_lanes_needed(struct mipi_csi2 *csi2,
+                                          struct v4l2_mbus_framefmt *format,
+                                          struct v4l2_fract *timeperframe)
+{
+       unsigned int bps_per_lane = 594000000U; /* FIXME */
+       unsigned int bpp = mipi_csi2_format_bpp(format->code);
+       unsigned int bps;
+
+       bps = format->width * format->height * bpp;
+       bps = mult_frac(bps, timeperframe->denominator, 
timeperframe->numerator);
+       return DIV_ROUND_UP(bps, bps_per_lane);
+}
+
+static int mipi_csi2_set_fmt(struct v4l2_subdev *sd,
+                            struct v4l2_subdev_pad_config *cfg,
+                            struct v4l2_subdev_format *sdformat)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+       unsigned long flags;
+       u32 val;
+
+       dev_dbg(csi2->dev, "%s\n", __func__);
+
+       if (sdformat->pad > 4)
+               return -EINVAL;
+
+       switch (sdformat->format.code) {
+       case MEDIA_BUS_FMT_RGB888_1X24:
+       case MEDIA_BUS_FMT_UYVY8_1X16:
+       case MEDIA_BUS_FMT_YUYV8_1X16:
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       csi2->format = sdformat->format;
+       csi2->lanes = mipi_csi2_lanes_needed(csi2, &csi2->format,
+                                            &csi2->timeperframe);
+
+       spin_lock_irqsave(&csi2->lock, flags);
+       val = readl(csi2->regs + CSI2IPU_SW_RST);
+       switch (csi2->format.code) {
+       case MEDIA_BUS_FMT_UYVY8_1X16:
+               val &= ~CSI2IPU_YUV422_8BIT_FM;
+               break;
+       case MEDIA_BUS_FMT_YUYV8_1X16:
+               val |= CSI2IPU_YUV422_8BIT_FM;
+               break;
+       }
+       writel(val, csi2->regs + CSI2IPU_SW_RST);
+       spin_unlock_irqrestore(&csi2->lock, flags);
+
+       return 0;
+}
+
+static int mipi_csi2_g_frame_interval(struct v4l2_subdev *sd,
+                                     struct v4l2_subdev_frame_interval *fi)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+
+       dev_dbg(csi2->dev, "%s\n", __func__);
+
+       fi->interval = csi2->timeperframe;
+
+       return 0;
+}
+
+static int mipi_csi2_s_frame_interval(struct v4l2_subdev *sd,
+                                     struct v4l2_subdev_frame_interval *fi)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+
+       dev_dbg(csi2->dev, "%s(%d, %d/%d)\n", __func__, fi->pad,
+               fi->interval.numerator, fi->interval.denominator);
+
+       if (fi->pad > 4)
+               return -EINVAL;
+
+       if (fi->pad > 0) {
+               fi->interval = csi2->timeperframe;
+
+               return 0;
+       }
+
+       csi2->timeperframe = fi->interval;
+       csi2->lanes = mipi_csi2_lanes_needed(csi2, &csi2->format,
+                                            &csi2->timeperframe);
+
+       return 0;
+}
+
+
+static const struct v4l2_subdev_pad_ops mipi_csi2_pad_ops = {
+       .get_fmt = mipi_csi2_get_fmt,
+       .set_fmt = mipi_csi2_set_fmt,
+};
+
+static int mipi_csi2_g_mbus_config(struct v4l2_subdev *sd,
+                           struct v4l2_mbus_config *cfg)
+{
+       cfg->type = V4L2_MBUS_CSI2;
+       cfg->flags = V4L2_MBUS_CSI2_1_LANE | V4L2_MBUS_CSI2_2_LANE |
+                    V4L2_MBUS_CSI2_3_LANE | V4L2_MBUS_CSI2_4_LANE |
+                    V4L2_MBUS_CSI2_CHANNEL_0 | V4L2_MBUS_CSI2_CHANNEL_1 |
+                    V4L2_MBUS_CSI2_CHANNEL_2 | V4L2_MBUS_CSI2_CHANNEL_3 |
+                    V4L2_MBUS_CSI2_CONTINUOUS_CLOCK |
+                    V4L2_MBUS_CSI2_NONCONTINUOUS_CLOCK;
+
+       return 0;
+}
+
+static int mipi_csi2_enable(struct mipi_csi2 *csi2)
+{
+       if (csi2->enabled)
+               return -EBUSY;
+
+       clk_prepare_enable(csi2->pclk);
+       clk_prepare_enable(csi2->cfg_clk);
+       clk_prepare_enable(csi2->ref_clk);
+       csi2->enabled = true;
+
+       return 0;
+}
+
+static int mipi_csi2_disable(struct mipi_csi2 *csi2)
+{
+       if (!csi2->enabled)
+               return 0;
+
+       clk_disable_unprepare(csi2->ref_clk);
+       clk_disable_unprepare(csi2->cfg_clk);
+       clk_disable_unprepare(csi2->pclk);
+       csi2->enabled = false;
+
+       return 0;
+}
+
+static int mipi_csi2_wait(struct mipi_csi2 *csi2, u8 reg, u32 mask, u32 val)
+{
+       unsigned long timeout = jiffies + msecs_to_jiffies(100);
+       u32 state;
+
+       dev_dbg(csi2->dev, "wait for register 0x%02x & 0x%08x to be 0x%08x\n",
+               reg, mask, val);
+
+       for (;;) {
+               state = readl(csi2->regs + reg);
+               dev_dbg(csi2->dev, "register 0x%02x == 0x%08x\n", reg, state);
+               if ((state & mask) == val)
+                       return 0;
+               if (time_after(jiffies, timeout))
+                       return -ETIMEDOUT;
+               usleep_range(500, 2000);
+       }
+}
+
+static inline unsigned int mipi_csi2_stop_state(unsigned int lanes)
+{
+       switch (lanes) {
+       case 1:
+               return PHY_STOPSTATEDATA_0 |
+                      PHY_STOPSTATECLK;
+       case 2:
+               return PHY_STOPSTATEDATA_0 | PHY_STOPSTATEDATA_1 |
+                      PHY_STOPSTATECLK;
+       case 3:
+               return PHY_STOPSTATEDATA_0 | PHY_STOPSTATEDATA_1 |
+                      PHY_STOPSTATEDATA_2 |
+                      PHY_STOPSTATECLK;
+       case 4:
+               return PHY_STOPSTATEDATA_0 | PHY_STOPSTATEDATA_1 |
+                      PHY_STOPSTATEDATA_2 | PHY_STOPSTATEDATA_3 |
+                      PHY_STOPSTATECLK;
+       default:
+               return 0;
+       }
+}
+
+/**
+ * mipi_csi2_prepare_stream - prepare for streaming
+ *
+ * The sender should be configured to put all lanes in PL-11 state (STOPSTATE)
+ * in its prepare_stream(), which must be called prior to this function.
+ * Afterwards, the sender shall start sending data in its s_stream().
+ */
+static int mipi_csi2_prepare_stream(struct v4l2_subdev *sd)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+       unsigned int stop_state;
+       int ret;
+
+       if (csi2->lanes > csi2->max_lanes) {
+               dev_err(csi2->dev, "%d lanes needed for format, %d supported\n",
+                       csi2->lanes, csi2->max_lanes);
+               return -EINVAL;
+       }
+
+       stop_state = mipi_csi2_stop_state(csi2->lanes);
+       if (!stop_state)
+               return -EINVAL;
+
+       if (csi2->enabled) {
+               dev_warn(csi2->dev, "Already enabled, disabling\n");
+               mipi_csi2_disable(csi2);
+               usleep_range(1000, 2000);
+       }
+
+       /* Enable clocks */
+       mipi_csi2_enable(csi2);
+
+       /* Set number of lanes */
+       writel(csi2->lanes - 1, csi2->regs + MIPI_CSI2_N_LANES);
+
+       /* Reset D-PHY and host controller */
+       mipi_csi2_reset(csi2);
+
+       /* Wait for STOP state on all used lanes */
+       ret = mipi_csi2_wait(csi2, MIPI_CSI2_PHY_STATE,
+                            stop_state, stop_state);
+       if (ret < 0) {
+               dev_err(csi2->dev,
+                       "Timeout waiting for lanes to enter STOP state\n");
+       }
+
+       return ret;
+}
+
+/**
+ * mipi_csi2_s_stream - start streaming
+ *
+ * When enabling streaming, the active lanes must have been detected to be in
+ * stop state in prepare_stream(), and the sender should now be sending data.
+ */
+static int mipi_csi2_s_stream(struct v4l2_subdev *sd, int enable)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+       struct v4l2_subdev *upstream_sd;
+       struct media_pad *pad;
+       int ret;
+
+       if (enable)
+               mipi_csi2_prepare_stream(sd);
+
+       pad = media_entity_remote_pad(&sd->entity.pads[0]);
+       if (!pad) {
+               dev_err(sd->dev, "Failed to find remote source pad\n");
+               return -ENOLINK;
+       }
+
+       if (!is_media_entity_v4l2_subdev(pad->entity)) {
+               dev_err(sd->dev, "Upstream entity is not a v4l2 subdev\n");
+               return -ENODEV;
+       }
+
+       upstream_sd = media_entity_to_v4l2_subdev(pad->entity);
+
+       ret = v4l2_subdev_call(upstream_sd, video, s_stream, enable);
+       if (ret)
+               return ret;
+
+       if (enable) {
+               /* Wait for PHY lock */
+               ret = mipi_csi2_wait(csi2, MIPI_CSI2_PHY_STATE,
+                                    PHY_RXCLKACTIVEHS, PHY_RXCLKACTIVEHS);
+               if (ret < 0) {
+                       dev_err(csi2->dev, "Timeout waiting for PHY lock\n");
+                       return ret;
+               }
+
+               /* Wait for error free transmission */
+               ret = mipi_csi2_wait(csi2, MIPI_CSI2_ERR1, ~0, 0);
+               if (ret < 0)
+                       dev_err(csi2->dev, "Timeout waiting for ERR1 to 
clear\n");
+
+               clk_prepare_enable(csi2->pixel_clk);
+               csi2->streaming = true;
+       } else {
+               if (csi2->streaming) {
+                       clk_disable_unprepare(csi2->pixel_clk);
+                       csi2->streaming = false;
+               }
+               mipi_csi2_disable(csi2);
+       }
+
+       return 0;
+}
+
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+static int mipi_csi2_log_status(struct v4l2_subdev *sd)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+       u32 val;
+       int i;
+
+       v4l2_info(sd, "-----MIPI CSI-2 Host status-----\n");
+       for (i = MIPI_CSI2_VERSION; i < MIPI_CSI2_PHY_TST_CTRL0; i += 4) {
+               val = readl(csi2->regs + i);
+               v4l2_info(sd, "%02x: %08x\n", i, val);
+       }
+
+       v4l2_info(sd, "-----CSI2IPU gasket status------\n");
+       val = readl(csi2->regs + CSI2IPU_SW_RST);
+       v4l2_info(sd, "f00: %08x\n", val);
+
+       return 0;
+}
+
+static int mipi_csi2_g_register(struct v4l2_subdev *sd,
+                               struct v4l2_dbg_register *reg)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+
+       if ((reg->reg % 4) ||
+           (reg->reg > MIPI_CSI2_PHY_TST_CTRL1 && reg->reg != CSI2IPU_SW_RST))
+               return -EINVAL;
+
+       reg->val = readl(csi2->regs + reg->reg);
+       reg->size = 4;
+
+       return 0;
+}
+
+static int mipi_csi2_s_register(struct v4l2_subdev *sd,
+                               const struct v4l2_dbg_register *reg)
+{
+       struct mipi_csi2 *csi2 = container_of(sd, struct mipi_csi2, subdev);
+
+       if ((reg->reg % 4) ||
+           (reg->reg == MIPI_CSI2_VERSION) ||
+           (reg->reg > MIPI_CSI2_PHY_TST_CTRL1 && reg->reg != CSI2IPU_SW_RST))
+               return -EINVAL;
+
+       writel(reg->val, csi2->regs + reg->reg);
+
+       return 0;
+}
+#endif
+
+static const struct v4l2_subdev_core_ops mipi_csi2_core_ops = {
+#ifdef CONFIG_VIDEO_ADV_DEBUG
+       .log_status = mipi_csi2_log_status,
+       .g_register = mipi_csi2_g_register,
+       .s_register = mipi_csi2_s_register,
+#endif
+};
+
+static const struct v4l2_subdev_video_ops mipi_csi2_video_ops = {
+       .g_frame_interval = mipi_csi2_g_frame_interval,
+       .s_frame_interval = mipi_csi2_s_frame_interval,
+       .g_mbus_config = mipi_csi2_g_mbus_config,
+       .s_stream = mipi_csi2_s_stream,
+};
+
+static const struct v4l2_subdev_internal_ops mipi_csi2_internal_ops = {
+       .registered = v4l2_of_subdev_registered,
+};
+
+static struct v4l2_subdev_ops mipi_csi2_subdev_ops = {
+       .core = &mipi_csi2_core_ops,
+       .pad = &mipi_csi2_pad_ops,
+       .video = &mipi_csi2_video_ops,
+};
+
+static int mipi_csi2_link_setup(struct media_entity *entity,
+                               const struct media_pad *local,
+                               const struct media_pad *remote, u32 flags)
+{
+       return 0;
+}
+
+static struct media_entity_operations mipi_csi2_entity_ops = {
+       .link_setup = mipi_csi2_link_setup,
+};
+
+static int mipi_csi2_probe(struct platform_device *pdev)
+{
+       struct resource *res;
+       struct mipi_csi2 *csi2;
+       struct device_node *ep;
+       unsigned int version;
+       int ret;
+       u32 val;
+
+       csi2 = devm_kzalloc(&pdev->dev, sizeof(*csi2), GFP_KERNEL);
+       if (!csi2)
+               return -ENOMEM;
+
+       spin_lock_init(&csi2->lock);
+
+       csi2->dev = &pdev->dev;
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       csi2->regs = devm_ioremap_resource(csi2->dev, res);
+       if (IS_ERR(csi2->regs))
+               return PTR_ERR(csi2->regs);
+
+       csi2->pclk = devm_clk_get(csi2->dev, "pclk");
+       if (IS_ERR(csi2->pclk))
+               return PTR_ERR(csi2->pclk);
+
+       csi2->cfg_clk = devm_clk_get(csi2->dev, "cfg");
+       if (IS_ERR(csi2->cfg_clk))
+               return PTR_ERR(csi2->cfg_clk);
+
+       csi2->ref_clk = devm_clk_get(csi2->dev, "ref");
+       if (IS_ERR(csi2->ref_clk))
+               return PTR_ERR(csi2->ref_clk);
+
+       csi2->pixel_clk = devm_clk_get(csi2->dev, "pixel");
+       if (IS_ERR(csi2->pixel_clk))
+               return PTR_ERR(csi2->pixel_clk);
+
+       platform_set_drvdata(pdev, csi2);
+
+       v4l2_subdev_init(&csi2->subdev, &mipi_csi2_subdev_ops);
+       csi2->subdev.internal_ops = &mipi_csi2_internal_ops;
+       snprintf(csi2->subdev.name, sizeof(csi2->subdev.name), "mipi-csi2");
+       csi2->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+       csi2->subdev.dev = &pdev->dev;
+
+       csi2->pads[0].flags = MEDIA_PAD_FL_SINK;
+       csi2->pads[1].flags = MEDIA_PAD_FL_SOURCE;
+       csi2->pads[2].flags = MEDIA_PAD_FL_SOURCE;
+       csi2->pads[3].flags = MEDIA_PAD_FL_SOURCE;
+       csi2->pads[4].flags = MEDIA_PAD_FL_SOURCE;
+       ret = media_entity_pads_init(&csi2->subdev.entity, MIPI_CSI2_PADS,
+                               csi2->pads);
+       if (ret < 0)
+               return ret;
+
+       csi2->subdev.entity.ops = &mipi_csi2_entity_ops;
+
+       clk_prepare_enable(csi2->pclk);
+
+       version = readl(csi2->regs + MIPI_CSI2_VERSION);
+       if (version != MIPI_CSI2_VERSION_IMX6) {
+               dev_err(csi2->dev, "Unknown version: 0x%x\n", version);
+               return -ENODEV;
+       }
+
+       /* Maximal number of data lanes */
+       csi2->max_lanes = readl(csi2->regs + MIPI_CSI2_N_LANES) + 1;
+
+       ret = v4l2_async_register_subdev(&csi2->subdev);
+       if (ret < 0)
+               return ret;
+
+       for_each_endpoint_of_node(pdev->dev.of_node, ep) {
+               struct v4l2_of_endpoint endpoint;
+
+               v4l2_of_parse_endpoint(ep, &endpoint);
+               if (endpoint.base.port != 0)
+                       continue;
+
+               if (endpoint.bus_type != V4L2_MBUS_CSI2) {
+                       dev_err(csi2->dev, "missing MIPI CSI-2 endpoint\n");
+                       return -EINVAL;
+               }
+
+               if (csi2->max_lanes < endpoint.bus.mipi_csi2.num_data_lanes) {
+                       dev_warn(csi2->dev, "only %d data lanes supported\n",
+                                csi2->max_lanes);
+               }
+
+               if (endpoint.bus.mipi_csi2.num_data_lanes &&
+                   endpoint.bus.mipi_csi2.num_data_lanes < csi2->max_lanes) {
+                       csi2->max_lanes = endpoint.bus.mipi_csi2.num_data_lanes;
+                       dev_dbg(csi2->dev, "only using %d data lanes\n",
+                               csi2->max_lanes);
+               }
+       }
+
+       csi2->timeperframe.numerator = 1;
+       csi2->timeperframe.denominator = 60;
+       csi2->lanes = csi2->max_lanes;
+
+       /*
+        * According to the i.MX6 Reference Manual, MIPI CSI-2 has to use
+        * the 'non-gated' (noncontinuous) clock mode, still the CLK_SEL
+        * bit in CSI2IPU_SW_RST needs to be cleared (marked as 'gated')
+        */
+       val = readl(csi2->regs + CSI2IPU_SW_RST);
+       val &= ~CSI2IPU_CLK_SEL;
+       writel(val, csi2->regs + CSI2IPU_SW_RST);
+
+       return 0;
+}
+
+static int mipi_csi2_remove(struct platform_device *pdev)
+{
+       return 0;
+}
+
+static const struct of_device_id mipi_csi2_dt_ids[] = {
+       { .compatible = "fsl,imx6q-mipi-csi2", },
+       { }
+};
+MODULE_DEVICE_TABLE(of, mipi_csi2_dt_ids);
+
+static struct platform_driver mipi_csi2_driver = {
+       .probe = mipi_csi2_probe,
+       .remove = mipi_csi2_remove,
+       .driver = {
+               .of_match_table = mipi_csi2_dt_ids,
+               .name = "mipi-csi2",
+               .owner = THIS_MODULE,
+       },
+};
+
+module_platform_driver(mipi_csi2_driver);
+
+MODULE_DESCRIPTION("i.MX MIPI CSI-2 Host Controller driver");
+MODULE_AUTHOR("Philipp Zabel, Pengutronix");
+MODULE_LICENSE("GPL");
-- 
2.9.3

--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to