[PATCH v3 21/24] media: imx: Add MIPI CSI-2 Receiver subdev driver

From: Steve Longerbeam
Date: Fri Jan 06 2017 - 21:15:40 EST


Adds MIPI CSI-2 Receiver subdev driver. This subdev is required
for sensors with a MIPI CSI2 interface.

Signed-off-by: Steve Longerbeam <steve_longerbeam@xxxxxxxxxx>
---
drivers/staging/media/imx/Makefile | 1 +
drivers/staging/media/imx/imx-mipi-csi2.c | 501 ++++++++++++++++++++++++++++++
2 files changed, 502 insertions(+)
create mode 100644 drivers/staging/media/imx/imx-mipi-csi2.c

diff --git a/drivers/staging/media/imx/Makefile b/drivers/staging/media/imx/Makefile
index fe9e992..0decef7 100644
--- a/drivers/staging/media/imx/Makefile
+++ b/drivers/staging/media/imx/Makefile
@@ -9,3 +9,4 @@ obj-$(CONFIG_VIDEO_IMX_MEDIA) += imx-ic.o
obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-csi.o
obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-smfc.o
obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-camif.o
+obj-$(CONFIG_VIDEO_IMX_CAMERA) += imx-mipi-csi2.o
diff --git a/drivers/staging/media/imx/imx-mipi-csi2.c b/drivers/staging/media/imx/imx-mipi-csi2.c
new file mode 100644
index 0000000..daa6e1d
--- /dev/null
+++ b/drivers/staging/media/imx/imx-mipi-csi2.c
@@ -0,0 +1,501 @@
+/*
+ * MIPI CSI-2 Receiver Subdev for Freescale i.MX5/6 SOC.
+ *
+ * Copyright (c) 2012-2014 Mentor Graphics Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-of.h>
+#include <media/v4l2-subdev.h>
+#include <video/imx-ipu-v3.h>
+#include "imx-media.h"
+
+/*
+ * there must be 5 pads: 1 input pad from sensor, and
+ * the 4 virtual channel output pads
+ */
+#define CSI2_NUM_SINK_PADS 1
+#define CSI2_NUM_SRC_PADS 4
+#define CSI2_NUM_PADS 5
+
+struct imxcsi2_dev {
+ struct device *dev;
+ struct imx_media_dev *md;
+ struct v4l2_subdev sd;
+ struct media_pad pad[CSI2_NUM_PADS];
+ struct v4l2_mbus_framefmt format_mbus;
+ struct v4l2_subdev *src_sd;
+ struct v4l2_subdev *sink_sd[CSI2_NUM_SRC_PADS];
+ int input_pad;
+ struct clk *dphy_clk;
+ struct clk *cfg_clk;
+ struct clk *pix_clk; /* what is this? */
+ void __iomem *base;
+ int intr1;
+ int intr2;
+ struct v4l2_of_bus_mipi_csi2 bus;
+ bool on;
+ bool stream_on;
+};
+
+#define DEVICE_NAME "imx6-mipi-csi2"
+
+/* Register offsets */
+#define CSI2_VERSION 0x000
+#define CSI2_N_LANES 0x004
+#define CSI2_PHY_SHUTDOWNZ 0x008
+#define CSI2_DPHY_RSTZ 0x00c
+#define CSI2_RESETN 0x010
+#define CSI2_PHY_STATE 0x014
+#define CSI2_DATA_IDS_1 0x018
+#define CSI2_DATA_IDS_2 0x01c
+#define CSI2_ERR1 0x020
+#define CSI2_ERR2 0x024
+#define CSI2_MSK1 0x028
+#define CSI2_MSK2 0x02c
+#define CSI2_PHY_TST_CTRL0 0x030
+#define CSI2_PHY_TST_CTRL1 0x034
+#define CSI2_SFT_RESET 0xf00
+
+static inline struct imxcsi2_dev *sd_to_dev(struct v4l2_subdev *sdev)
+{
+ return container_of(sdev, struct imxcsi2_dev, sd);
+}
+
+static inline u32 imxcsi2_read(struct imxcsi2_dev *csi2, unsigned int regoff)
+{
+ return readl(csi2->base + regoff);
+}
+
+static inline void imxcsi2_write(struct imxcsi2_dev *csi2, u32 val,
+ unsigned int regoff)
+{
+ writel(val, csi2->base + regoff);
+}
+
+static void imxcsi2_set_lanes(struct imxcsi2_dev *csi2)
+{
+ int lanes = csi2->bus.num_data_lanes;
+
+ imxcsi2_write(csi2, lanes - 1, CSI2_N_LANES);
+}
+
+static void imxcsi2_enable(struct imxcsi2_dev *csi2, bool enable)
+{
+ if (enable) {
+ imxcsi2_write(csi2, 0xffffffff, CSI2_PHY_SHUTDOWNZ);
+ imxcsi2_write(csi2, 0xffffffff, CSI2_DPHY_RSTZ);
+ imxcsi2_write(csi2, 0xffffffff, CSI2_RESETN);
+ } else {
+ imxcsi2_write(csi2, 0x0, CSI2_PHY_SHUTDOWNZ);
+ imxcsi2_write(csi2, 0x0, CSI2_DPHY_RSTZ);
+ imxcsi2_write(csi2, 0x0, CSI2_RESETN);
+ }
+}
+
+static void imxcsi2_reset(struct imxcsi2_dev *csi2)
+{
+ imxcsi2_enable(csi2, false);
+
+ imxcsi2_write(csi2, 0x00000001, CSI2_PHY_TST_CTRL0);
+ imxcsi2_write(csi2, 0x00000000, CSI2_PHY_TST_CTRL1);
+ imxcsi2_write(csi2, 0x00000000, CSI2_PHY_TST_CTRL0);
+ imxcsi2_write(csi2, 0x00000002, CSI2_PHY_TST_CTRL0);
+ imxcsi2_write(csi2, 0x00010044, CSI2_PHY_TST_CTRL1);
+ imxcsi2_write(csi2, 0x00000000, CSI2_PHY_TST_CTRL0);
+ imxcsi2_write(csi2, 0x00000014, CSI2_PHY_TST_CTRL1);
+ imxcsi2_write(csi2, 0x00000002, CSI2_PHY_TST_CTRL0);
+ imxcsi2_write(csi2, 0x00000000, CSI2_PHY_TST_CTRL0);
+
+ imxcsi2_enable(csi2, true);
+}
+
+static int imxcsi2_dphy_wait(struct imxcsi2_dev *csi2)
+{
+ u32 reg;
+ int i;
+
+ /* wait for mipi sensor ready */
+ for (i = 0; i < 50; i++) {
+ reg = imxcsi2_read(csi2, CSI2_PHY_STATE);
+ if (reg != 0x200)
+ break;
+ usleep_range(10000, 20000);
+ }
+
+ if (i >= 50) {
+ v4l2_err(&csi2->sd,
+ "wait for clock lane timeout, phy_state = 0x%08x\n",
+ reg);
+ return -ETIME;
+ }
+
+ /* wait for mipi stable */
+ for (i = 0; i < 50; i++) {
+ reg = imxcsi2_read(csi2, CSI2_ERR1);
+ if (reg == 0x0)
+ break;
+ usleep_range(10000, 20000);
+ }
+
+ if (i >= 50) {
+ v4l2_err(&csi2->sd,
+ "wait for controller timeout, err1 = 0x%08x\n",
+ reg);
+ return -ETIME;
+ }
+
+ /* finally let's wait for active clock on the clock lane */
+ for (i = 0; i < 50; i++) {
+ reg = imxcsi2_read(csi2, CSI2_PHY_STATE);
+ if (reg & (1 << 8))
+ break;
+ usleep_range(10000, 20000);
+ }
+
+ if (i >= 50) {
+ v4l2_err(&csi2->sd,
+ "wait for active clock timeout, phy_state = 0x%08x\n",
+ reg);
+ return -ETIME;
+ }
+
+ v4l2_info(&csi2->sd, "ready, dphy version 0x%x\n",
+ imxcsi2_read(csi2, CSI2_VERSION));
+
+ return 0;
+}
+
+/*
+ * V4L2 subdev operations
+ */
+
+static int imxcsi2_link_setup(struct media_entity *entity,
+ const struct media_pad *local,
+ const struct media_pad *remote, u32 flags)
+{
+ struct v4l2_subdev *sd = media_entity_to_v4l2_subdev(entity);
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+ struct v4l2_subdev *remote_sd;
+
+ dev_dbg(csi2->dev, "link setup %s -> %s", remote->entity->name,
+ local->entity->name);
+
+ remote_sd = media_entity_to_v4l2_subdev(remote->entity);
+
+ if (local->flags & MEDIA_PAD_FL_SOURCE) {
+ if (flags & MEDIA_LNK_FL_ENABLED) {
+ if (csi2->sink_sd[local->index])
+ return -EBUSY;
+ csi2->sink_sd[local->index] = remote_sd;
+ } else {
+ csi2->sink_sd[local->index] = NULL;
+ }
+ } else {
+ if (flags & MEDIA_LNK_FL_ENABLED) {
+ if (csi2->src_sd)
+ return -EBUSY;
+ csi2->src_sd = remote_sd;
+ } else {
+ csi2->src_sd = NULL;
+ }
+ }
+
+ return 0;
+}
+
+static int imxcsi2_s_power(struct v4l2_subdev *sd, int on)
+{
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+
+ if (on && !csi2->on) {
+ v4l2_info(&csi2->sd, "power ON\n");
+ clk_prepare_enable(csi2->cfg_clk);
+ clk_prepare_enable(csi2->dphy_clk);
+ imxcsi2_set_lanes(csi2);
+ imxcsi2_reset(csi2);
+ } else if (!on && csi2->on) {
+ v4l2_info(&csi2->sd, "power OFF\n");
+ imxcsi2_enable(csi2, false);
+ clk_disable_unprepare(csi2->dphy_clk);
+ clk_disable_unprepare(csi2->cfg_clk);
+ }
+
+ csi2->on = on;
+ return 0;
+}
+
+static int imxcsi2_s_stream(struct v4l2_subdev *sd, int enable)
+{
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+ int i, ret = 0;
+
+ if (!csi2->src_sd)
+ return -EPIPE;
+ for (i = 0; i < CSI2_NUM_SRC_PADS; i++) {
+ if (csi2->sink_sd[i])
+ break;
+ }
+ if (i >= CSI2_NUM_SRC_PADS)
+ return -EPIPE;
+
+ v4l2_info(sd, "stream %s\n", enable ? "ON" : "OFF");
+
+ if (enable && !csi2->stream_on) {
+ ret = clk_prepare_enable(csi2->pix_clk);
+ if (ret)
+ return ret;
+
+ ret = imxcsi2_dphy_wait(csi2);
+ if (ret) {
+ clk_disable_unprepare(csi2->pix_clk);
+ return ret;
+ }
+ } else if (!enable && csi2->stream_on) {
+ clk_disable_unprepare(csi2->pix_clk);
+ }
+
+ csi2->stream_on = enable;
+ return 0;
+}
+
+static int imxcsi2_get_fmt(struct v4l2_subdev *sd,
+ struct v4l2_subdev_pad_config *cfg,
+ struct v4l2_subdev_format *sdformat)
+{
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+
+ sdformat->format = csi2->format_mbus;
+
+ return 0;
+}
+
+static int imxcsi2_set_fmt(struct v4l2_subdev *sd,
+ struct v4l2_subdev_pad_config *cfg,
+ struct v4l2_subdev_format *sdformat)
+{
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+
+ if (sdformat->pad >= CSI2_NUM_PADS)
+ return -EINVAL;
+
+ if (csi2->stream_on)
+ return -EBUSY;
+
+ /* Output pads mirror active input pad, no limits on input pads */
+ if (sdformat->pad != csi2->input_pad)
+ sdformat->format = csi2->format_mbus;
+
+ if (sdformat->which == V4L2_SUBDEV_FORMAT_TRY)
+ cfg->try_fmt = sdformat->format;
+ else
+ csi2->format_mbus = sdformat->format;
+
+ return 0;
+}
+
+/*
+ * retrieve our pads parsed from the OF graph by the media device
+ */
+static int imxcsi2_registered(struct v4l2_subdev *sd)
+{
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+ struct imx_media_subdev *imxsd;
+ struct imx_media_pad *pad;
+ int i, ret;
+
+ /* get media device */
+ csi2->md = dev_get_drvdata(sd->v4l2_dev->dev);
+
+ imxsd = imx_media_find_subdev_by_sd(csi2->md, sd);
+ if (IS_ERR(imxsd))
+ return PTR_ERR(imxsd);
+
+ if (imxsd->num_sink_pads != 1 || imxsd->num_src_pads != 4)
+ return -EINVAL;
+
+ for (i = 0; i < CSI2_NUM_PADS; i++) {
+ pad = &imxsd->pad[i];
+ csi2->pad[i] = pad->pad;
+ if (csi2->pad[i].flags & MEDIA_PAD_FL_SINK)
+ csi2->input_pad = i;
+ }
+
+ /* set a default mbus format */
+ ret = imx_media_init_mbus_fmt(&csi2->format_mbus,
+ 640, 480, 0, V4L2_FIELD_NONE, NULL);
+ if (ret)
+ return ret;
+
+ return media_entity_pads_init(&sd->entity, CSI2_NUM_PADS, csi2->pad);
+}
+
+static struct media_entity_operations imxcsi2_entity_ops = {
+ .link_setup = imxcsi2_link_setup,
+ .link_validate = v4l2_subdev_link_validate,
+};
+
+static struct v4l2_subdev_core_ops imxcsi2_core_ops = {
+ .s_power = imxcsi2_s_power,
+};
+
+static struct v4l2_subdev_video_ops imxcsi2_video_ops = {
+ .s_stream = imxcsi2_s_stream,
+};
+
+static struct v4l2_subdev_pad_ops imxcsi2_pad_ops = {
+ .get_fmt = imxcsi2_get_fmt,
+ .set_fmt = imxcsi2_set_fmt,
+};
+
+static struct v4l2_subdev_ops imxcsi2_subdev_ops = {
+ .core = &imxcsi2_core_ops,
+ .video = &imxcsi2_video_ops,
+ .pad = &imxcsi2_pad_ops,
+};
+
+static struct v4l2_subdev_internal_ops imxcsi2_internal_ops = {
+ .registered = imxcsi2_registered,
+};
+
+static int imxcsi2_parse_endpoints(struct imxcsi2_dev *csi2)
+{
+ struct device_node *node = csi2->dev->of_node;
+ struct device_node *epnode;
+ struct v4l2_of_endpoint ep;
+
+ epnode = of_graph_get_next_endpoint(node, NULL);
+ if (!epnode) {
+ v4l2_err(&csi2->sd, "failed to get endpoint node\n");
+ return -EINVAL;
+ }
+
+ v4l2_of_parse_endpoint(epnode, &ep);
+ of_node_put(epnode);
+
+ if (ep.bus_type != V4L2_MBUS_CSI2) {
+ v4l2_err(&csi2->sd, "invalid bus type, must be MIPI CSI2\n");
+ return -EINVAL;
+ }
+
+ csi2->bus = ep.bus.mipi_csi2;
+
+ v4l2_info(&csi2->sd, "data lanes: %d\n", csi2->bus.num_data_lanes);
+ v4l2_info(&csi2->sd, "flags: 0x%08x\n", csi2->bus.flags);
+ return 0;
+}
+
+static int imxcsi2_probe(struct platform_device *pdev)
+{
+ struct imxcsi2_dev *csi2;
+ struct resource *res;
+ int ret;
+
+ csi2 = devm_kzalloc(&pdev->dev, sizeof(*csi2), GFP_KERNEL);
+ if (!csi2)
+ return -ENOMEM;
+
+ csi2->dev = &pdev->dev;
+
+ v4l2_subdev_init(&csi2->sd, &imxcsi2_subdev_ops);
+ v4l2_set_subdevdata(&csi2->sd, &pdev->dev);
+ csi2->sd.internal_ops = &imxcsi2_internal_ops;
+ csi2->sd.entity.ops = &imxcsi2_entity_ops;
+ csi2->sd.dev = &pdev->dev;
+ csi2->sd.owner = THIS_MODULE;
+ csi2->sd.flags = V4L2_SUBDEV_FL_HAS_DEVNODE;
+ strcpy(csi2->sd.name, DEVICE_NAME);
+ csi2->sd.entity.function = MEDIA_ENT_F_VID_IF_BRIDGE;
+ csi2->sd.grp_id = IMX_MEDIA_GRP_ID_CSI2;
+
+ ret = imxcsi2_parse_endpoints(csi2);
+ if (ret)
+ return ret;
+
+ csi2->cfg_clk = devm_clk_get(&pdev->dev, "cfg");
+ if (IS_ERR(csi2->cfg_clk)) {
+ v4l2_err(&csi2->sd, "failed to get cfg clock\n");
+ ret = PTR_ERR(csi2->cfg_clk);
+ return ret;
+ }
+
+ csi2->dphy_clk = devm_clk_get(&pdev->dev, "dphy");
+ if (IS_ERR(csi2->dphy_clk)) {
+ v4l2_err(&csi2->sd, "failed to get dphy clock\n");
+ ret = PTR_ERR(csi2->dphy_clk);
+ return ret;
+ }
+
+ csi2->pix_clk = devm_clk_get(&pdev->dev, "pix");
+ if (IS_ERR(csi2->pix_clk)) {
+ v4l2_err(&csi2->sd, "failed to get pixel clock\n");
+ ret = PTR_ERR(csi2->pix_clk);
+ return ret;
+ }
+
+ csi2->intr1 = platform_get_irq(pdev, 0);
+ csi2->intr2 = platform_get_irq(pdev, 1);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+
+ if (!res || csi2->intr1 < 0 || csi2->intr2 < 0) {
+ v4l2_err(&csi2->sd, "failed to get platform resources\n");
+ return -ENODEV;
+ }
+
+ csi2->base = devm_ioremap(&pdev->dev, res->start, PAGE_SIZE);
+ if (!csi2->base) {
+ v4l2_err(&csi2->sd, "failed to map CSI-2 registers\n");
+ return -ENOMEM;
+ }
+
+ platform_set_drvdata(pdev, &csi2->sd);
+
+ return v4l2_async_register_subdev(&csi2->sd);
+}
+
+static int imxcsi2_remove(struct platform_device *pdev)
+{
+ struct v4l2_subdev *sd = platform_get_drvdata(pdev);
+ struct imxcsi2_dev *csi2 = sd_to_dev(sd);
+
+ imxcsi2_s_power(sd, 0);
+
+ v4l2_async_unregister_subdev(&csi2->sd);
+ media_entity_cleanup(&csi2->sd.entity);
+ v4l2_device_unregister_subdev(sd);
+
+ return 0;
+}
+
+static const struct of_device_id imxcsi2_dt_ids[] = {
+ { .compatible = "fsl,imx6-mipi-csi2", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imxcsi2_dt_ids);
+
+static struct platform_driver imxcsi2_driver = {
+ .driver = {
+ .name = DEVICE_NAME,
+ .of_match_table = imxcsi2_dt_ids,
+ },
+ .probe = imxcsi2_probe,
+ .remove = imxcsi2_remove,
+};
+
+module_platform_driver(imxcsi2_driver);
+
+MODULE_DESCRIPTION("i.MX5/6 MIPI CSI-2 Receiver driver");
+MODULE_AUTHOR("Steve Longerbeam <steve_longerbeam@xxxxxxxxxx>");
+MODULE_LICENSE("GPL");
+
--
2.7.4