Hi Tomasz,
Thanks for the review.
On Thu, 2020-06-18 at 19:10 +0000, Tomasz Figa wrote:
> Hi Dongchun,
>
> On Mon, Jun 15, 2020 at 08:29:37PM +0800, Dongchun Zhu wrote:
> > Add a V4L2 sub-device driver for OV02A10 image sensor.
> >
> > Signed-off-by: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
> > ---
> > MAINTAINERS | 1 +
> > drivers/media/i2c/Kconfig | 13 +
> > drivers/media/i2c/Makefile | 1 +
> > drivers/media/i2c/ov02a10.c | 1042 +++++++++++++++++++++++++++++++++++++++++++
> > 4 files changed, 1057 insertions(+)
> > create mode 100644 drivers/media/i2c/ov02a10.c
> >
>
> Thank you for the patch. Please see my comments inline.
>
> [snip]
> > +static int ov02a10_set_fmt(struct v4l2_subdev *sd,
> > + struct v4l2_subdev_pad_config *cfg,
> > + struct v4l2_subdev_format *fmt)
> > +{
> > + struct ov02a10 *ov02a10 = to_ov02a10(sd);
> > + struct v4l2_mbus_framefmt *mbus_fmt = &fmt->format;
> > +
> > + mutex_lock(&ov02a10->mutex);
> > +
> > + if (ov02a10->streaming) {
> > + mutex_unlock(&ov02a10->mutex);
> > + return -EBUSY;
> > + }
> > +
> > + /* Only one sensor mode supported */
> > + mbus_fmt->code = ov02a10->fmt.code;
> > + ov02a10_fill_fmt(ov02a10->cur_mode, mbus_fmt);
> > + ov02a10->fmt = fmt->format;
> > +
> > + if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
> > + *v4l2_subdev_get_try_format(sd, cfg, fmt->pad) = fmt->format;
>
> If fmt->which is V4L2_SUBDEV_FORMAT_TRY, the internal driver state must not
> be affected. It also should not depend on whether the sensor is streaming
> or not. Basically it should be considered a special "candidate" format,
> which isn't programmed to the hardware, but just stored aside.
>
Hmm. Maybe we shall use FORMAT_TRY like this:
struct v4l2_mbus_framefmt *frame_fmt;
...
if (fmt->which == V4L2_SUBDEV_FORMAT_TRY)
frame_fmt = v4l2_subdev_get_try_format(sd, cfg, 0);
else
frame_fmt = &ov02a10->fmt;
*frame_fmt = *mbus_fmt;
(Remove 'ov02a10->fmt = fmt->format;' above)
> > +
> > + mutex_unlock(&ov02a10->mutex);
> > +
> > + return 0;
> > +}
> [snip]
> > +static int ov02a10_power_on(struct device *dev)
> > +{
> > + struct i2c_client *client = to_i2c_client(dev);
> > + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > + struct ov02a10 *ov02a10 = to_ov02a10(sd);
> > + int ret;
> > +
> > + gpiod_set_value_cansleep(ov02a10->rst_gpio, 0);
>
> As we discussed before, the pin names mean their logical function and the
> polarity means the function is active. In this case, we want to _activate_
> the _reset_ so it should be 1.
>
Yes, you are right.
Sorry that made a mistake about powerdown/reset GPIO polarity settings.
For instance, _reset_ pin shall be active low, not active high.
The following state setting need to update as well.
> > + gpiod_set_value_cansleep(ov02a10->pd_gpio, 0);
>
> I believe we don't want to deactivate the powerdown yet. First the clock
> and regulator need to be enabled.
>
Fixed in next release.
> > +
> > + ret = clk_prepare_enable(ov02a10->eclk);
> > + if (ret < 0) {
> > + dev_err(dev, "failed to enable eclk\n");
> > + return ret;
> > + }
> > +
> > + ret = regulator_bulk_enable(ARRAY_SIZE(ov02a10_supply_names),
> > + ov02a10->supplies);
> > + if (ret < 0) {
> > + dev_err(dev, "failed to enable regulators\n");
> > + goto disable_clk;
> > + }
> > + usleep_range(5000, 6000);
> > +
> > + gpiod_set_value_cansleep(ov02a10->pd_gpio, 1);
>
> Here we want to *deactivate* the powerdown, so the value should be 0.
>
Fixed in next release.
> > + usleep_range(5000, 6000);
> > +
> > + gpiod_set_value_cansleep(ov02a10->rst_gpio, 1);
>
> And here we want to *deactivate* the reset so it should be 0.
>
Fixed in next release.
> > + usleep_range(5000, 6000);
> > +
> > + ret = ov02a10_check_sensor_id(ov02a10);
> > + if (ret)
> > + goto disable_regulator;
> > +
> > + return 0;
> > +
> > +disable_regulator:
> > + regulator_bulk_disable(ARRAY_SIZE(ov02a10_supply_names),
> > + ov02a10->supplies);
> > +disable_clk:
> > + clk_disable_unprepare(ov02a10->eclk);
> > +
> > + return ret;
> > +}
> > +
> > +static int ov02a10_power_off(struct device *dev)
> > +{
> > + struct i2c_client *client = to_i2c_client(dev);
> > + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > + struct ov02a10 *ov02a10 = to_ov02a10(sd);
> > +
> > + gpiod_set_value_cansleep(ov02a10->rst_gpio, 0);
>
> We want to *activate* reset here, so it should be 1.
>
Fixed in next release.
> > + clk_disable_unprepare(ov02a10->eclk);
> > + gpiod_set_value_cansleep(ov02a10->pd_gpio, 0);
>
> We want to *activate* powerdown here, so should be 1 too.
>
Fixed in next release.
> > + regulator_bulk_disable(ARRAY_SIZE(ov02a10_supply_names),
> > + ov02a10->supplies);
> > +
> > + return 0;
> > +}
> [snip]
> > +static int ov02a10_probe(struct i2c_client *client)
> > +{
> > + struct device *dev = &client->dev;
> > + struct ov02a10 *ov02a10;
> > + unsigned int rotation;
> > + unsigned int clock_lane_tx_speed;
> > + unsigned int i;
> > + int ret;
> > +
> > + ov02a10 = devm_kzalloc(dev, sizeof(*ov02a10), GFP_KERNEL);
> > + if (!ov02a10)
> > + return -ENOMEM;
> > +
> > + ret = ov02a10_check_hwcfg(dev, ov02a10);
> > + if (ret) {
> > + dev_err(dev, "failed to check HW configuration: %d", ret);
> > + return ret;
> > + }
> > +
> > + v4l2_i2c_subdev_init(&ov02a10->subdev, client, &ov02a10_subdev_ops);
> > + ov02a10->mipi_clock_tx_speed = OV02A10_MIPI_TX_SPEED_DEFAULT;
> > + ov02a10->fmt.code = MEDIA_BUS_FMT_SBGGR10_1X10;
> > +
> > + /* Optional indication of physical rotation of sensor */
> > + ret = fwnode_property_read_u32(dev_fwnode(dev), "rotation", &rotation);
> > + if (!ret && rotation == 180) {
> > + ov02a10->upside_down = true;
> > + ov02a10->fmt.code = MEDIA_BUS_FMT_SRGGB10_1X10;
> > + }
> > +
> > + /* Optional indication of mipi TX speed */
> > + ret = fwnode_property_read_u32(dev_fwnode(dev), "ovti,mipi-tx-speed",
> > + &clock_lane_tx_speed);
> > +
> > + if (!ret)
> > + ov02a10->mipi_clock_tx_speed = clock_lane_tx_speed;
> > +
> > + /* Get system clock (eclk) */
> > + ov02a10->eclk = devm_clk_get(dev, "eclk");
> > + if (IS_ERR(ov02a10->eclk)) {
> > + ret = PTR_ERR(ov02a10->eclk);
> > + dev_err(dev, "failed to get eclk %d\n", ret);
> > + return ret;
> > + }
> > +
> > + ret = fwnode_property_read_u32(dev_fwnode(dev), "clock-frequency",
> > + &ov02a10->eclk_freq);
> > + if (ret) {
> > + dev_err(dev, "failed to get eclk frequency\n");
> > + return ret;
> > + }
> > +
> > + ret = clk_set_rate(ov02a10->eclk, ov02a10->eclk_freq);
> > + if (ret) {
> > + dev_err(dev, "failed to set eclk frequency (24MHz)\n");
> > + return ret;
> > + }
> > +
> > + if (clk_get_rate(ov02a10->eclk) != OV02A10_ECLK_FREQ) {
> > + dev_warn(dev, "wrong eclk frequency %d Hz, expected: %d Hz\n",
> > + ov02a10->eclk_freq, OV02A10_ECLK_FREQ);
> > + return -EINVAL;
> > + }
> > +
> > + ov02a10->pd_gpio = devm_gpiod_get(dev, "powerdown", GPIOD_OUT_HIGH);
> > + if (IS_ERR(ov02a10->pd_gpio)) {
> > + ret = PTR_ERR(ov02a10->pd_gpio);
> > + dev_err(dev, "failed to get powerdown-gpios %d\n", ret);
> > + return ret;
> > + }
> > +
> > + ov02a10->rst_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
> > + if (IS_ERR(ov02a10->rst_gpio)) {
> > + ret = PTR_ERR(ov02a10->rst_gpio);
> > + dev_err(dev, "failed to get reset-gpios %d\n", ret);
> > + return ret;
> > + }
> > +
> > + for (i = 0; i < ARRAY_SIZE(ov02a10_supply_names); i++)
> > + ov02a10->supplies[i].supply = ov02a10_supply_names[i];
> > +
> > + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ov02a10_supply_names),
> > + ov02a10->supplies);
> > + if (ret) {
> > + dev_err(dev, "failed to get regulators\n");
> > + return ret;
> > + }
> > +
> > + mutex_init(&ov02a10->mutex);
> > + ov02a10->cur_mode = &supported_modes[0];
> > + ret = ov02a10_initialize_controls(ov02a10);
> > + if (ret) {
> > + dev_err(dev, "failed to initialize controls\n");
> > + goto err_destroy_mutex;
> > + }
> > +
> > + ov02a10->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> > + ov02a10->subdev.entity.ops = &ov02a10_subdev_entity_ops;
> > + ov02a10->subdev.entity.function = MEDIA_ENT_F_CAM_SENSOR;
> > + ov02a10->pad.flags = MEDIA_PAD_FL_SOURCE;
> > + ret = media_entity_pads_init(&ov02a10->subdev.entity, 1, &ov02a10->pad);
> > + if (ret < 0) {
> > + dev_err(dev, "failed to init entity pads: %d", ret);
> > + goto err_free_handler;
> > + }
> > +
> > + pm_runtime_enable(dev);
> > + if (!pm_runtime_enabled(dev)) {
> > + ret = ov02a10_power_on(dev);
> > + if (ret < 0) {
> > + dev_err(dev, "failed to power on: %d\n", ret);
> > + goto err_clean_entity;
> > + }
> > + }
> > +
> > + ret = v4l2_async_register_subdev(&ov02a10->subdev);
> > + if (ret) {
> > + dev_err(dev, "failed to register V4L2 subdev: %d", ret);
> > + goto err_power_off;
> > + }
> > +
> > + return 0;
> > +
> > +err_power_off:
> > + pm_runtime_disable(dev);
> > + if (!pm_runtime_enabled(dev))
>
> This would be always true, resulting in unbalanced power off. Moving
> pm_runtime_disable() after this if should work better.
>
Yes. Fixed in next release.
> > + ov02a10_power_off(dev);
> > +err_clean_entity:
> > + media_entity_cleanup(&ov02a10->subdev.entity);
> > +err_free_handler:
> > + v4l2_ctrl_handler_free(ov02a10->subdev.ctrl_handler);
> > +err_destroy_mutex:
> > + mutex_destroy(&ov02a10->mutex);
> > +
> > + return ret;
> > +}
> > +
> > +static int ov02a10_remove(struct i2c_client *client)
> > +{
> > + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> > + struct ov02a10 *ov02a10 = to_ov02a10(sd);
> > +
> > + v4l2_async_unregister_subdev(sd);
> > + media_entity_cleanup(&sd->entity);
> > + v4l2_ctrl_handler_free(sd->ctrl_handler);
> > + pm_runtime_disable(&client->dev);
> > + if (!pm_runtime_suspended(&client->dev))
>
> Sorry, similarly to the dw9768 driver, I made a mistake and suggested the
> wrong function. pm_runtime_status_suspended() should be correct here.
>
That's OK.
Fixed in next release.
> Best regards,
> Tomasz
