On Tue, Jun 16, 2020 at 08:55:31PM +0800, Dongchun Zhu wrote:
> Add a V4L2 sub-device driver for DW9768 voice coil motor,
> providing control to set the desired focus via IIC serial interface.
>
> Signed-off-by: Dongchun Zhu <dongchun.zhu@xxxxxxxxxxxx>
> ---
> MAINTAINERS | 1 +
> drivers/media/i2c/Kconfig | 12 +
> drivers/media/i2c/Makefile | 1 +
> drivers/media/i2c/dw9768.c | 553 +++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 567 insertions(+)
> create mode 100644 drivers/media/i2c/dw9768.c
[snip]
> +static int dw9768_probe(struct i2c_client *client)
> +{
> + struct device *dev = &client->dev;
> + struct dw9768 *dw9768;
> + unsigned int i;
> + int ret;
> +
> + dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
> + if (!dw9768)
> + return -ENOMEM;
> +
> + /* Initialize subdev */
> + v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
> +
> + dw9768->aac_mode = DW9768_AAC_MODE_DEFAULT;
> + dw9768->aac_timing = DW9768_AAC_TIME_DEFAULT;
> + dw9768->clock_presc = DW9768_CLOCK_PRE_SCALE_DEFAULT;
> +
> + /* Optional indication of AAC mode select */
> + fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-mode",
> + &dw9768->aac_mode);
> +
> + /* Optional indication of clock pre-scale select */
> + fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,clock-presc",
> + &dw9768->clock_presc);
> +
> + /* Optional indication of AAC Timing */
> + fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-timing",
> + &dw9768->aac_timing);
> +
> + dw9768->move_delay_us = dw9768_cal_move_delay(dw9768->aac_mode,
> + dw9768->clock_presc,
> + dw9768->aac_timing) / 100;
nit: Could we make the function return the value in us already? One would
expect the function to return the value in a standard unit, so this
division by 100 here is confusing.
> +
> + for (i = 0; i < ARRAY_SIZE(dw9768_supply_names); i++)
> + dw9768->supplies[i].supply = dw9768_supply_names[i];
> +
> + ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dw9768_supply_names),
> + dw9768->supplies);
> + if (ret) {
> + dev_err(dev, "failed to get regulators\n");
> + return ret;
> + }
> +
> + /* Initialize controls */
> + ret = dw9768_init_controls(dw9768);
> + if (ret)
> + goto err_free_handler;
> +
> + /* Initialize subdev */
> + dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> + dw9768->sd.internal_ops = &dw9768_int_ops;
> +
> + ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
> + if (ret < 0)
> + goto err_free_handler;
> +
> + dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
> +
> + pm_runtime_enable(dev);
> + if (!pm_runtime_enabled(dev)) {
> + ret = dw9768_runtime_resume(dev);
> + if (ret < 0) {
> + dev_err(dev, "failed to power on: %d\n", ret);
> + goto err_clean_entity;
> + }
> + }
> +
> + ret = v4l2_async_register_subdev(&dw9768->sd);
> + if (ret < 0) {
> + 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))
We just disabled runtime PM in the line above, so this check would be
always true. Need to call pm_runtime_disable() after this if.
> + dw9768_runtime_suspend(dev);
> +err_clean_entity:
> + media_entity_cleanup(&dw9768->sd.entity);
> +err_free_handler:
> + v4l2_ctrl_handler_free(&dw9768->ctrls);
> +
> + return ret;
> +}
> +
> +static int dw9768_remove(struct i2c_client *client)
> +{
> + struct v4l2_subdev *sd = i2c_get_clientdata(client);
> + struct dw9768 *dw9768 = sd_to_dw9768(sd);
> +
> + v4l2_async_unregister_subdev(&dw9768->sd);
> + v4l2_ctrl_handler_free(&dw9768->ctrls);
> + media_entity_cleanup(&dw9768->sd.entity);
> + pm_runtime_disable(&client->dev);
> + if (!pm_runtime_suspended(&client->dev))
Oops, I just realized that my suggestion about the function to use here
was incorrect. pm_runtime_status_suspended() should be the correct function
here. Sorry for the confusion.
This is because we only have 2 cases here:
- runtime PM compiled out - the stubs function is used, which returns
false, so the condition is true,
- runtime PM compiled in - we enabled runtime PM in probe, so here we
don't need to consider the enable state.
Best regards,
Tomasz
