[PATCH v3 13/14] [media] marvell-ccic: use async notifier to get the sensor

From: Lubomir Rintel
Date: Tue Nov 20 2018 - 05:04:35 EST

An instance of a sensor on DT-based MMP2 platform is always going to be
created asynchronously.

Let's move the manual device creation away from the core to the Cafe
driver (used on OLPC XO-1, not present in DT) and set up appropriate
async matches: I2C on Cafe, FWNODE on MMP (OLPC XO-1.75).

Signed-off-by: Lubomir Rintel <lkundrak@xxxxx>

---
Changes since v2:
- Moved a typo fix hunk that was accidentally in the following patch
here, to unbreak build.

.../media/platform/marvell-ccic/cafe-driver.c | 49 ++++--
.../media/platform/marvell-ccic/mcam-core.c | 157 ++++++++++++------
.../media/platform/marvell-ccic/mcam-core.h | 5 +-
.../media/platform/marvell-ccic/mmp-driver.c | 27 +--
.../linux/platform_data/media/mmp-camera.h | 1 -
5 files changed, 162 insertions(+), 77 deletions(-)

diff --git a/drivers/media/platform/marvell-ccic/cafe-driver.c b/drivers/media/platform/marvell-ccic/cafe-driver.c
index 2986cb4b88d0..658294d319c0 100644
--- a/drivers/media/platform/marvell-ccic/cafe-driver.c
+++ b/drivers/media/platform/marvell-ccic/cafe-driver.c
@@ -8,6 +8,7 @@
*
* Copyright 2006-11 One Laptop Per Child Association, Inc.
* Copyright 2006-11 Jonathan Corbet <corbet@xxxxxxx>
+ * Copyright 2018 Lubomir Rintel <lkundrak@xxxxx>
*
* Written by Jonathan Corbet, corbet@xxxxxxxx
*
@@ -27,6 +28,7 @@
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <media/v4l2-device.h>
+#include <media/i2c/ov7670.h>
#include <linux/device.h>
#include <linux/wait.h>
#include <linux/delay.h>
@@ -52,6 +54,7 @@ struct cafe_camera {
int registered; /* Fully initialized? */
struct mcam_camera mcam;
struct pci_dev *pdev;
+ struct i2c_adapter *i2c_adapter;
wait_queue_head_t smbus_wait; /* Waiting on i2c events */
};

@@ -351,15 +354,15 @@ static int cafe_smbus_setup(struct cafe_camera *cam)
return ret;
}

- cam->mcam.i2c_adapter = adap;
+ cam->i2c_adapter = adap;
cafe_smbus_enable_irq(cam);
return 0;
}

static void cafe_smbus_shutdown(struct cafe_camera *cam)
{
- i2c_del_adapter(cam->mcam.i2c_adapter);
- kfree(cam->mcam.i2c_adapter);
+ i2c_del_adapter(cam->i2c_adapter);
+ kfree(cam->i2c_adapter);
}


@@ -452,6 +455,29 @@ static irqreturn_t cafe_irq(int irq, void *data)
return IRQ_RETVAL(handled);
}

+/* -------------------------------------------------------------------------- */
+
+static struct ov7670_config sensor_cfg = {
+ /*
+ * Exclude QCIF mode, because it only captures a tiny portion
+ * of the sensor FOV
+ */
+ .min_width = 320,
+ .min_height = 240,
+
+ /*
+ * Set the clock speed for the XO 1; I don't believe this
+ * driver has ever run anywhere else.
+ */
+ .clock_speed = 45,
+ .use_smbus = 1,
+};
+
+struct i2c_board_info ov7670_info = {
+ .type = "ov7670",
+ .addr = 0x42 >> 1,
+ .platform_data = &sensor_cfg,
+};

/* -------------------------------------------------------------------------- */
/*
@@ -481,12 +507,6 @@ static int cafe_pci_probe(struct pci_dev *pdev,
mcam->plat_power_down = cafe_ctlr_power_down;
mcam->dev = &pdev->dev;
snprintf(mcam->bus_info, sizeof(mcam->bus_info), "PCI:%s", pci_name(pdev));
- /*
- * Set the clock speed for the XO 1; I don't believe this
- * driver has ever run anywhere else.
- */
- mcam->clock_speed = 45;
- mcam->use_smbus = 1;
/*
* Vmalloc mode for buffers is traditional with this driver.
* We *might* be able to run DMA_contig, especially on a system
@@ -527,12 +547,21 @@ static int cafe_pci_probe(struct pci_dev *pdev,
if (ret)
goto out_pdown;

+ mcam->asd.match_type = V4L2_ASYNC_MATCH_I2C;
+ mcam->asd.match.i2c.adapter_id = i2c_adapter_id(cam->i2c_adapter);
+ mcam->asd.match.i2c.address = ov7670_info.addr;
+
ret = mccic_register(mcam);
- if (ret == 0) {
+ if (ret)
+ goto out_smbus_shutdown;
+
+ if (i2c_new_device(cam->i2c_adapter, &ov7670_info)) {
cam->registered = 1;
return 0;
}

+ mccic_shutdown(mcam);
+out_smbus_shutdown:
cafe_smbus_shutdown(cam);
out_pdown:
cafe_ctlr_power_down(mcam);
diff --git a/drivers/media/platform/marvell-ccic/mcam-core.c b/drivers/media/platform/marvell-ccic/mcam-core.c
index 0113b8d37d03..87812b7287f0 100644
--- a/drivers/media/platform/marvell-ccic/mcam-core.c
+++ b/drivers/media/platform/marvell-ccic/mcam-core.c
@@ -4,6 +4,7 @@
* so it needs platform-specific support outside of the core.
*
* Copyright 2011 Jonathan Corbet corbet@xxxxxxx
+ * Copyright 2018 Lubomir Rintel <lkundrak@xxxxx>
*/
#include <linux/kernel.h>
#include <linux/module.h>
@@ -26,7 +27,6 @@
#include <media/v4l2-ioctl.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-event.h>
-#include <media/i2c/ov7670.h>
#include <media/videobuf2-vmalloc.h>
#include <media/videobuf2-dma-contig.h>
#include <media/videobuf2-dma-sg.h>
@@ -93,6 +93,9 @@ MODULE_PARM_DESC(buffer_mode,
#define sensor_call(cam, o, f, args...) \
v4l2_subdev_call(cam->sensor, o, f, ##args)

+#define notifier_to_mcam(notifier) \
+ container_of(notifier, struct mcam_camera, notifier)
+
static struct mcam_format_struct {
__u8 *desc;
__u32 pixelformat;
@@ -1715,23 +1718,94 @@ EXPORT_SYMBOL_GPL(mccic_irq);
/*
* Registration and such.
*/
-static struct ov7670_config sensor_cfg = {
+
+static int mccic_notify_bound(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *subdev, struct v4l2_async_subdev *asd)
+{
+ struct mcam_camera *cam = notifier_to_mcam(notifier);
+ int ret;
+
+ mutex_lock(&cam->s_mutex);
+ if (cam->sensor) {
+ cam_err(cam, "sensor already bound\n");
+ ret = -EBUSY;
+ goto out;
+ }
+
+ v4l2_set_subdev_hostdata(subdev, cam);
+ cam->sensor = subdev;
+
+ ret = mcam_cam_init(cam);
+ if (ret) {
+ cam->sensor = NULL;
+ goto out;
+ }
+
+ ret = mcam_setup_vb2(cam);
+ if (ret) {
+ cam->sensor = NULL;
+ goto out;
+ }
+
+ cam->vdev = mcam_v4l_template;
+ cam->vdev.v4l2_dev = &cam->v4l2_dev;
+ cam->vdev.lock = &cam->s_mutex;
+ cam->vdev.queue = &cam->vb_queue;
+ video_set_drvdata(&cam->vdev, cam);
+ ret = video_register_device(&cam->vdev, VFL_TYPE_GRABBER, -1);
+ if (ret) {
+ cam->sensor = NULL;
+ goto out;
+ }
+
+ cam_dbg(cam, "sensor %s bound\n", subdev->name);
+out:
+ mutex_unlock(&cam->s_mutex);
+ return ret;
+}
+
+static void mccic_notify_unbind(struct v4l2_async_notifier *notifier,
+ struct v4l2_subdev *subdev, struct v4l2_async_subdev *asd)
+{
+ struct mcam_camera *cam = notifier_to_mcam(notifier);
+
+ mutex_lock(&cam->s_mutex);
+ if (cam->sensor != subdev) {
+ cam_err(cam, "sensor %s not bound\n", subdev->name);
+ goto out;
+ }
+
+ video_unregister_device(&cam->vdev);
+ cam->sensor = NULL;
+ cam_dbg(cam, "sensor %s unbound\n", subdev->name);
+
+out:
+ mutex_unlock(&cam->s_mutex);
+}
+
+static int mccic_notify_complete(struct v4l2_async_notifier *notifier)
+{
+ struct mcam_camera *cam = notifier_to_mcam(notifier);
+ int ret;
+
/*
- * Exclude QCIF mode, because it only captures a tiny portion
- * of the sensor FOV
+ * Get the v4l2 setup done.
*/
- .min_width = 320,
- .min_height = 240,
-};
+ ret = v4l2_ctrl_handler_init(&cam->ctrl_handler, 10);
+ if (!ret)
+ cam->v4l2_dev.ctrl_handler = &cam->ctrl_handler;
+
+ return ret;
+}

+static const struct v4l2_async_notifier_operations mccic_notify_ops = {
+ .bound = mccic_notify_bound,
+ .unbind = mccic_notify_unbind,
+ .complete = mccic_notify_complete,
+};

int mccic_register(struct mcam_camera *cam)
{
- struct i2c_board_info ov7670_info = {
- .type = "ov7670",
- .addr = 0x42 >> 1,
- .platform_data = &sensor_cfg,
- };
int ret;

/*
@@ -1744,17 +1818,20 @@ int mccic_register(struct mcam_camera *cam)
printk(KERN_ERR "marvell-cam: Cafe can't do S/G I/O, attempting vmalloc mode instead\n");
cam->buffer_mode = B_vmalloc;
}
+
if (!mcam_buffer_mode_supported(cam->buffer_mode)) {
printk(KERN_ERR "marvell-cam: buffer mode %d unsupported\n",
cam->buffer_mode);
- return -EINVAL;
+ ret = -EINVAL;
+ goto out;
}
+
/*
* Register with V4L
*/
ret = v4l2_device_register(cam->dev, &cam->v4l2_dev);
if (ret)
- return ret;
+ goto out;

mutex_init(&cam->s_mutex);
cam->state = S_NOTREADY;
@@ -1764,43 +1841,20 @@ int mccic_register(struct mcam_camera *cam)
mcam_ctlr_init(cam);

/*
- * Get the v4l2 setup done.
+ * Register sensor notifier.
*/
- ret = v4l2_ctrl_handler_init(&cam->ctrl_handler, 10);
- if (ret)
- goto out_unregister;
- cam->v4l2_dev.ctrl_handler = &cam->ctrl_handler;
-
- /*
- * Try to find the sensor.
- */
- sensor_cfg.clock_speed = cam->clock_speed;
- sensor_cfg.use_smbus = cam->use_smbus;
- cam->sensor = v4l2_i2c_new_subdev_board(&cam->v4l2_dev,
- cam->i2c_adapter, &ov7670_info, NULL);
- if (cam->sensor == NULL) {
- ret = -ENODEV;
- goto out_unregister;
+ v4l2_async_notifier_init(&cam->notifier);
+ ret = v4l2_async_notifier_add_subdev(&cam->notifier, &cam->asd);
+ if (ret) {
+ cam_warn(cam, "failed to add subdev to a notifier");
+ goto out;
}

- ret = mcam_cam_init(cam);
- if (ret)
- goto out_unregister;
-
- ret = mcam_setup_vb2(cam);
- if (ret)
- goto out_unregister;
-
- mutex_lock(&cam->s_mutex);
- cam->vdev = mcam_v4l_template;
- cam->vdev.v4l2_dev = &cam->v4l2_dev;
- cam->vdev.lock = &cam->s_mutex;
- cam->vdev.queue = &cam->vb_queue;
- video_set_drvdata(&cam->vdev, cam);
- ret = video_register_device(&cam->vdev, VFL_TYPE_GRABBER, -1);
- if (ret) {
- mutex_unlock(&cam->s_mutex);
- goto out_unregister;
+ cam->notifier.ops = &mccic_notify_ops;
+ ret = v4l2_async_notifier_register(&cam->v4l2_dev, &cam->notifier);
+ if (ret < 0) {
+ cam_warn(cam, "failed to register a sensor notifier");
+ goto out;
}

/*
@@ -1811,11 +1865,10 @@ int mccic_register(struct mcam_camera *cam)
cam_warn(cam, "Unable to alloc DMA buffers at load will try again later.");
}

- mutex_unlock(&cam->s_mutex);
return 0;

-out_unregister:
- v4l2_ctrl_handler_free(&cam->ctrl_handler);
+out:
+ v4l2_async_notifier_unregister(&cam->notifier);
v4l2_device_unregister(&cam->v4l2_dev);
return ret;
}
@@ -1835,8 +1888,8 @@ void mccic_shutdown(struct mcam_camera *cam)
}
if (cam->buffer_mode == B_vmalloc)
mcam_free_dma_bufs(cam);
- video_unregister_device(&cam->vdev);
v4l2_ctrl_handler_free(&cam->ctrl_handler);
+ v4l2_async_notifier_unregister(&cam->notifier);
v4l2_device_unregister(&cam->v4l2_dev);
}
EXPORT_SYMBOL_GPL(mccic_shutdown);
diff --git a/drivers/media/platform/marvell-ccic/mcam-core.h b/drivers/media/platform/marvell-ccic/mcam-core.h
index b828b1bb59d3..4a72213aca1a 100644
--- a/drivers/media/platform/marvell-ccic/mcam-core.h
+++ b/drivers/media/platform/marvell-ccic/mcam-core.h
@@ -102,14 +102,11 @@ struct mcam_camera {
* These fields should be set by the platform code prior to
* calling mcam_register().
*/
- struct i2c_adapter *i2c_adapter;
unsigned char __iomem *regs;
unsigned regs_size; /* size in bytes of the register space */
spinlock_t dev_lock;
struct device *dev; /* For messages, dma alloc */
enum mcam_chip_id chip_id;
- short int clock_speed; /* Sensor clock speed, default 30 */
- short int use_smbus; /* SMBUS or straight I2c? */
enum mcam_buffer_mode buffer_mode;

int mclk_src; /* which clock source the mclk derives from */
@@ -150,6 +147,8 @@ struct mcam_camera {
* Subsystem structures.
*/
struct video_device vdev;
+ struct v4l2_async_notifier notifier;
+ struct v4l2_async_subdev asd;
struct v4l2_subdev *sensor;

/* Videobuf2 stuff */
diff --git a/drivers/media/platform/marvell-ccic/mmp-driver.c b/drivers/media/platform/marvell-ccic/mmp-driver.c
index 05b9fa8c6a6f..efbffb06e25c 100644
--- a/drivers/media/platform/marvell-ccic/mmp-driver.c
+++ b/drivers/media/platform/marvell-ccic/mmp-driver.c
@@ -3,6 +3,7 @@
* to work with the Armada 610 as used in the OLPC 1.75 system.
*
* Copyright 2011 Jonathan Corbet <corbet@xxxxxxx>
+ * Copyright 2018 Lubomir Rintel <lkundrak@xxxxx>
*
* This file may be distributed under the terms of the GNU General
* Public License, version 2.
@@ -11,7 +12,6 @@
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
-#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
@@ -316,6 +316,7 @@ static int mmpcam_probe(struct platform_device *pdev)
struct mmp_camera *cam;
struct mcam_camera *mcam;
struct resource *res;
+ struct fwnode_handle *ep;
struct mmp_camera_platform_data *pdata;
int ret;

@@ -330,7 +331,6 @@ static int mmpcam_probe(struct platform_device *pdev)
mcam->plat_power_down = mmpcam_power_down;
mcam->calc_dphy = mmpcam_calc_dphy;
mcam->dev = &pdev->dev;
- mcam->use_smbus = 0;
pdata = pdev->dev.platform_data;
if (pdata) {
mcam->mclk_src = pdata->mclk_src;
@@ -374,15 +374,6 @@ static int mmpcam_probe(struct platform_device *pdev)
cam->power_regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(cam->power_regs))
return PTR_ERR(cam->power_regs);
- /*
- * Find the i2c adapter. This assumes, of course, that the
- * i2c bus is already up and functioning.
- */
- mcam->i2c_adapter = platform_get_drvdata(pdata->i2c_device);
- if (mcam->i2c_adapter == NULL) {
- dev_err(&pdev->dev, "No i2c adapter\n");
- return -ENODEV;
- }
/*
* Sensor GPIO pins.
*/
@@ -405,6 +396,19 @@ static int mmpcam_probe(struct platform_device *pdev)

mcam_init_clk(mcam);

+ /*
+ * Create a match of the sensor against its OF node.
+ */
+ ep = fwnode_graph_get_next_endpoint(of_fwnode_handle(pdev->dev.of_node),
+ NULL);
+ if (!ep)
+ return -ENODEV;
+
+ mcam->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
+ mcam->asd.match.fwnode = fwnode_graph_get_remote_port_parent(ep);
+
+ fwnode_handle_put(ep);
+
/*
* Power the device up and hand it off to the core.
*/
@@ -414,6 +418,7 @@ static int mmpcam_probe(struct platform_device *pdev)
ret = mccic_register(mcam);
if (ret)
goto out_power_down;
+
/*
* Finally, set up our IRQ now that the core is ready to
* deal with it.
diff --git a/include/linux/platform_data/media/mmp-camera.h b/include/linux/platform_data/media/mmp-camera.h
index 4c3a80a45883..c573ebc40035 100644
--- a/include/linux/platform_data/media/mmp-camera.h
+++ b/include/linux/platform_data/media/mmp-camera.h
@@ -12,7 +12,6 @@ enum dphy3_algo {
};

struct mmp_camera_platform_data {
- struct platform_device *i2c_device;
int sensor_power_gpio;
int sensor_reset_gpio;
enum v4l2_mbus_type bus_type;
--
2.19.1