Re: [PATCH V2 6/8] soundwire: amd: add runtime pm ops for AMD soundwire manager driver

Pierre-Louis Bossart
2023-02-13T18:27:12Z

On 2/13/23 03:40, Vijendar Mukunda wrote:
> Add support for runtime pm ops for AMD soundwire manager driver.
>
> Signed-off-by: Vijendar Mukunda <Vijendar.Mukunda@amd.com>
> Signed-off-by: Mastan Katragadda <Mastan.Katragadda@amd.com>
> ---
> drivers/soundwire/amd_manager.c | 163 ++++++++++++++++++++++++++++++
> drivers/soundwire/amd_manager.h | 3 +
> include/linux/soundwire/sdw_amd.h | 16 +++
> 3 files changed, 182 insertions(+)
>
> diff --git a/drivers/soundwire/amd_manager.c b/drivers/soundwire/amd_manager.c
> index 87f9a987d93a..eced189ba6e0 100644
> --- a/drivers/soundwire/amd_manager.c
> +++ b/drivers/soundwire/amd_manager.c
> @@ -14,6 +14,7 @@
> #include <linux/slab.h>
> #include <linux/soundwire/sdw.h>
> #include <linux/soundwire/sdw_registers.h>
> +#include <linux/pm_runtime.h>
> #include <linux/wait.h>
> #include <sound/pcm_params.h>
> #include <sound/soc.h>
> @@ -185,6 +186,15 @@ static void amd_disable_sdw_interrupts(struct amd_sdw_manager *amd_manager)
> acp_reg_writel(0x00, amd_manager->mmio + ACP_SW_ERROR_INTR_MASK);
> }
>
> +static int amd_deinit_sdw_manager(struct amd_sdw_manager *amd_manager)
> +{
> + int ret;
> +
> + amd_disable_sdw_interrupts(amd_manager);
> + ret = amd_disable_sdw_manager(amd_manager);
> + return ret;
> +}
> +
> static void amd_sdw_set_frameshape(struct amd_sdw_manager *amd_manager)
> {
> u32 frame_size;
> @@ -1043,6 +1053,12 @@ static int amd_sdw_manager_probe(struct platform_device *pdev)
> INIT_WORK(&amd_manager->amd_sdw_work, amd_sdw_update_slave_status_work);
> INIT_WORK(&amd_manager->probe_work, amd_sdw_probe_work);
> schedule_work(&amd_manager->probe_work);
> + /* Enable runtime PM */
> + pm_runtime_set_autosuspend_delay(dev, AMD_SDW_MASTER_SUSPEND_DELAY_MS);
> + pm_runtime_use_autosuspend(dev);
> + pm_runtime_mark_last_busy(dev);
> + pm_runtime_set_active(dev);
> + pm_runtime_enable(dev);

that doesn't sound good to me, why do this here and not in the work
function? That creates a racy case where the device might suspend before
being initialized.

> return 0;
> }
>
> @@ -1057,14 +1073,161 @@ static int amd_sdw_manager_remove(struct platform_device *pdev)
> amd_disable_sdw_interrupts(amd_manager);
> sdw_bus_master_delete(&amd_manager->bus);
> ret = amd_disable_sdw_manager(amd_manager);
> + pm_runtime_disable(&pdev->dev);

shouldn't you do the pm_runtime_disable first?

> return ret;
> }

> +/* AMD pm_runtime quirk definitions */
> +
> +/*
> + * Force the clock to stop(ClockStopMode0) when suspend callback
> + * is invoked.
> + */
> +#define AMD_SDW_CLK_STOP_MODE 1
> +
> +/*
> + * Stop the bus when runtime suspend/system level suspend callback
> + * is invoked. If set, a complete bus reset and re-enumeration will
> + * be performed when the bus restarts.
> + */
> +#define AMD_SDW_POWER_OFF_MODE 2

You need to clarify this mode, can you deal with device in-band wakes if
the power is off?

> #define ACP_SDW0 0
> #define ACP_SDW1 1
>
> @@ -57,6 +71,7 @@ struct sdw_amd_dai_runtime {
> * @instance: soundwire manager instance
> * @quirks: soundwire manager quirks
> * @wake_en_mask: wake enable mask per soundwire manager
> + * @clk_stopped: flag set to true when clock is stopped
> * @power_mode_mask: flag interprets amd soundwire manager power mode
> * @dai_runtime_array: dai runtime array
> */
> @@ -86,6 +101,7 @@ struct amd_sdw_manager {
> u32 quirks;
> u32 wake_en_mask;
> u32 power_mode_mask;
> + bool clk_stopped;
>
> struct sdw_amd_dai_runtime **dai_runtime_array;
> };