| Message ID | 20200320162947.17663-6-pierre-louis.bossart@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | soundwire: add sdw_master_device support on Qualcomm platforms | expand |
On 20/03/2020 16:29, Pierre-Louis Bossart wrote: > Add new device as a child of the platform device, following the > following hierarchy: > > platform_device > sdw_master_device > sdw_slave0 Why can't we just remove the platform device layer here and add sdw_master_device directly? What is it stopping doing that? --srini > ... > sdw_slaveN > > For the Qualcomm implementation no sdw_master_driver is registered so > the dais have to be registered using the platform_device and likely > all power management is handled at the platform device level. > > Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> > --- > drivers/soundwire/qcom.c | 29 +++++++++++++++++++++++++---- > 1 file changed, 25 insertions(+), 4 deletions(-) > > diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c > index 77783ae4b71d..86b46415e50b 100644 > --- a/drivers/soundwire/qcom.c > +++ b/drivers/soundwire/qcom.c > @@ -89,6 +89,7 @@ struct qcom_swrm_port_config { > struct qcom_swrm_ctrl { > struct sdw_bus bus; > struct device *dev; > + struct sdw_master_device *md; > struct regmap *regmap; > struct completion *comp; > struct work_struct slave_work; > @@ -775,14 +776,31 @@ static int qcom_swrm_probe(struct platform_device *pdev) > mutex_init(&ctrl->port_lock); > INIT_WORK(&ctrl->slave_work, qcom_swrm_slave_wq); > > - ctrl->bus.dev = dev; > + /* > + * add sdw_master_device. > + * For the Qualcomm implementation there is no driver. > + */ > + ctrl->md = sdw_master_device_add(NULL, /* no driver name */ > + dev, /* platform device is parent */ > + dev->fwnode, > + 0, /* only one link supported */ > + NULL); /* no context */ > + if (IS_ERR(ctrl->md)) { > + dev_err(dev, "Could not create sdw_master_device\n"); > + ret = PTR_ERR(ctrl->md); > + goto err_clk; > + } > + > + /* the bus uses the sdw_master_device, not the platform device */ > + ctrl->bus.dev = &ctrl->md->dev; > + > ctrl->bus.ops = &qcom_swrm_ops; > ctrl->bus.port_ops = &qcom_swrm_port_ops; > ctrl->bus.compute_params = &qcom_swrm_compute_params; > > ret = qcom_swrm_get_port_config(ctrl); > if (ret) > - goto err_clk; > + goto err_md; > > params = &ctrl->bus.params; > params->max_dr_freq = DEFAULT_CLK_FREQ; > @@ -809,14 +827,14 @@ static int qcom_swrm_probe(struct platform_device *pdev) > "soundwire", ctrl); > if (ret) { > dev_err(dev, "Failed to request soundwire irq\n"); > - goto err_clk; > + goto err_md; > } > > ret = sdw_add_bus_master(&ctrl->bus); > if (ret) { > dev_err(dev, "Failed to register Soundwire controller (%d)\n", > ret); > - goto err_clk; > + goto err_md; > } > > qcom_swrm_init(ctrl); > @@ -832,6 +850,8 @@ static int qcom_swrm_probe(struct platform_device *pdev) > > err_master_add: > sdw_delete_bus_master(&ctrl->bus); > +err_md: > + device_unregister(&ctrl->md->dev); > err_clk: > clk_disable_unprepare(ctrl->hclk); > err_init: > @@ -843,6 +863,7 @@ static int qcom_swrm_remove(struct platform_device *pdev) > struct qcom_swrm_ctrl *ctrl = dev_get_drvdata(&pdev->dev); > > sdw_delete_bus_master(&ctrl->bus); > + device_unregister(&ctrl->md->dev); > clk_disable_unprepare(ctrl->hclk); > > return 0; >
>> Add new device as a child of the platform device, following the >> following hierarchy: >> >> platform_device >> sdw_master_device >> sdw_slave0 > > Why can't we just remove the platform device layer here and add > sdw_master_device directly? > > What is it stopping doing that? The guidance from Greg was "no platform devices, unless you really are on a platform bus (i.e. Device tree.)". We never discussed changing the way the Device Tree parts are handled. The main idea was to leave the parent (be it platform-device or PCI device) alone and not add new attributes or references to it. The scheme here is similar to I2C/SPI, you have a platform device handled by the Device Tree baseline, and a driver create an i2c_adapter/spi_controller/sdw_master_device.
On 20-03-20, 17:01, Srinivas Kandagatla wrote: > > > On 20/03/2020 16:29, Pierre-Louis Bossart wrote: > > Add new device as a child of the platform device, following the > > following hierarchy: > > > > platform_device > > sdw_master_device > > sdw_slave0 > > Why can't we just remove the platform device layer here and add > sdw_master_device directly? In the case platform_device is the OF device your controller gets probed on. My thinking on this is that drivers should not be directly creating sdw_master_device but it should be done by core as this device is for core to use and handle. Ideally I would love that sdw_master_device is created/handled by core, preferably this be handled as part of sdw_add_bus_master(). But Pierre is trying to solve the limitation of the devices given by ACPI and trying to add sdw_master_driver to handle that. I am not convinced that we should do that.
diff --git a/drivers/soundwire/qcom.c b/drivers/soundwire/qcom.c index 77783ae4b71d..86b46415e50b 100644 --- a/drivers/soundwire/qcom.c +++ b/drivers/soundwire/qcom.c @@ -89,6 +89,7 @@ struct qcom_swrm_port_config { struct qcom_swrm_ctrl { struct sdw_bus bus; struct device *dev; + struct sdw_master_device *md; struct regmap *regmap; struct completion *comp; struct work_struct slave_work; @@ -775,14 +776,31 @@ static int qcom_swrm_probe(struct platform_device *pdev) mutex_init(&ctrl->port_lock); INIT_WORK(&ctrl->slave_work, qcom_swrm_slave_wq); - ctrl->bus.dev = dev; + /* + * add sdw_master_device. + * For the Qualcomm implementation there is no driver. + */ + ctrl->md = sdw_master_device_add(NULL, /* no driver name */ + dev, /* platform device is parent */ + dev->fwnode, + 0, /* only one link supported */ + NULL); /* no context */ + if (IS_ERR(ctrl->md)) { + dev_err(dev, "Could not create sdw_master_device\n"); + ret = PTR_ERR(ctrl->md); + goto err_clk; + } + + /* the bus uses the sdw_master_device, not the platform device */ + ctrl->bus.dev = &ctrl->md->dev; + ctrl->bus.ops = &qcom_swrm_ops; ctrl->bus.port_ops = &qcom_swrm_port_ops; ctrl->bus.compute_params = &qcom_swrm_compute_params; ret = qcom_swrm_get_port_config(ctrl); if (ret) - goto err_clk; + goto err_md; params = &ctrl->bus.params; params->max_dr_freq = DEFAULT_CLK_FREQ; @@ -809,14 +827,14 @@ static int qcom_swrm_probe(struct platform_device *pdev) "soundwire", ctrl); if (ret) { dev_err(dev, "Failed to request soundwire irq\n"); - goto err_clk; + goto err_md; } ret = sdw_add_bus_master(&ctrl->bus); if (ret) { dev_err(dev, "Failed to register Soundwire controller (%d)\n", ret); - goto err_clk; + goto err_md; } qcom_swrm_init(ctrl); @@ -832,6 +850,8 @@ static int qcom_swrm_probe(struct platform_device *pdev) err_master_add: sdw_delete_bus_master(&ctrl->bus); +err_md: + device_unregister(&ctrl->md->dev); err_clk: clk_disable_unprepare(ctrl->hclk); err_init: @@ -843,6 +863,7 @@ static int qcom_swrm_remove(struct platform_device *pdev) struct qcom_swrm_ctrl *ctrl = dev_get_drvdata(&pdev->dev); sdw_delete_bus_master(&ctrl->bus); + device_unregister(&ctrl->md->dev); clk_disable_unprepare(ctrl->hclk); return 0;
Add new device as a child of the platform device, following the following hierarchy: platform_device sdw_master_device sdw_slave0 ... sdw_slaveN For the Qualcomm implementation no sdw_master_driver is registered so the dais have to be registered using the platform_device and likely all power management is handled at the platform device level. Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com> --- drivers/soundwire/qcom.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-)