Re: [PATCH 08/10] ASoC: cs35l56: Add driver for Cirrus Logic CS35L56

Pierre-Louis Bossart
2023-02-21T16:59:11Z

> +static int cs35l56_sdw_interrupt(struct sdw_slave *peripheral,
> + struct sdw_slave_intr_status *status)
> +{
> + struct cs35l56_private *cs35l56 = dev_get_drvdata(&peripheral->dev);
> +
> + /* SoundWire core holds our pm_runtime when calling this function. */
> +
> + dev_dbg(cs35l56->dev, "int control_port=%#x\n", status->control_port);
> +
> + if ((status->control_port & SDW_SCP_INT1_IMPL_DEF) == 0)
> + return 0;
> +
> + /* Prevent host controller suspending before we handle the interrupt */
> + pm_runtime_get_noresume(cs35l56->dev);

can this happen that the manager suspends in this function?

Or is this needed because of the queued work which the manager has no
knowledge of?

> +
> + /*
> + * Mask and clear until it has been handled. The read of GEN_INT_STAT_1
> + * is required as per the SoundWire spec for interrupt status bits
> + * to clear. GEN_INT_MASK_1 masks the _inputs_ to GEN_INT_STAT1.
> + * None of the interrupts are time-critical so use the
> + * power-efficient queue.
> + */
> + sdw_write_no_pm(peripheral, CS35L56_SDW_GEN_INT_MASK_1, 0);
> + sdw_read_no_pm(peripheral, CS35L56_SDW_GEN_INT_STAT_1);
> + sdw_write_no_pm(peripheral, CS35L56_SDW_GEN_INT_STAT_1, 0xFF);
> + queue_work(system_power_efficient_wq, &cs35l56->sdw_irq_work);
> +
> + return 0;
> +}

> +static int __maybe_unused cs35l56_sdw_handle_unattach(struct cs35l56_private *cs35l56)
> +{
> + struct sdw_slave *peripheral = cs35l56->sdw_peripheral;
> +
> + if (peripheral->unattach_request) {
> + /* Cannot access registers until master re-attaches. */

not sure what the comment means, the manager does not attach. did you
mean resume the bus?

> + dev_dbg(cs35l56->dev, "Wait for initialization_complete\n");
> + if (!wait_for_completion_timeout(&peripheral->initialization_complete,
> + msecs_to_jiffies(5000))) {
> + dev_err(cs35l56->dev, "initialization_complete timed out\n");
> + return -ETIMEDOUT;
> + }
> +
> + peripheral->unattach_request = 0;
> +
> + /*
> + * Don't call regcache_mark_dirty(), we can't be sure that the
> + * Manager really did issue a Bus Reset.
> + */
> + }
> +
> + return 0;
> +}
...

> +static void cs35l56_dsp_work(struct work_struct *work)
> +{
> + struct cs35l56_private *cs35l56 = container_of(work,
> + struct cs35l56_private,
> + dsp_work);
> + unsigned int reg;
> + unsigned int val;
> + int ret = 0;
> +
> + if (!wait_for_completion_timeout(&cs35l56->init_completion,
> + msecs_to_jiffies(5000))) {
> + dev_err(cs35l56->dev, "%s: init_completion timed out\n", __func__);
> + goto complete;
> + }
> +
> + if (!cs35l56->init_done || cs35l56->removing)
> + goto complete;
> +
> + cs35l56->dsp.part = devm_kasprintf(cs35l56->dev, GFP_KERNEL, "cs35l56%s-%02x",
> + cs35l56->secured ? "s" : "", cs35l56->rev);
> +
> + if (!cs35l56->dsp.part)
> + goto complete;
> +
> + pm_runtime_get_sync(cs35l56->dev);

test that this is successful?

> +
> + /*
> + * Disable SoundWire interrupts to prevent race with IRQ work.
> + * Setting sdw_irq_no_unmask prevents the handler re-enabling
> + * the SoundWire interrupt.
> + */
> + if (cs35l56->sdw_peripheral) {
> + cs35l56->sdw_irq_no_unmask = true;
> + cancel_work_sync(&cs35l56->sdw_irq_work);
> + sdw_write_no_pm(cs35l56->sdw_peripheral, CS35L56_SDW_GEN_INT_MASK_1, 0);
> + sdw_read_no_pm(cs35l56->sdw_peripheral, CS35L56_SDW_GEN_INT_STAT_1);
> + sdw_write_no_pm(cs35l56->sdw_peripheral, CS35L56_SDW_GEN_INT_STAT_1, 0xFF);
> + }
> +
> + ret = cs35l56_mbox_send(cs35l56, CS35L56_MBOX_CMD_SHUTDOWN);
> + if (ret) {
> + dev_dbg(cs35l56->dev, "%s: CS35L56_MBOX_CMD_SHUTDOWN ret %d\n", __func__, ret);
> + goto err;
> + }
> +
> + if (cs35l56->rev < CS35L56_REVID_B0)
> + reg = CS35L56_DSP1_PM_CUR_STATE_A1;
> + else
> + reg = CS35L56_DSP1_PM_CUR_STATE;
> +
> + ret = regmap_read_poll_timeout(cs35l56->regmap, reg,
> + val, (val == CS35L56_HALO_STATE_SHUTDOWN),
> + CS35L56_HALO_STATE_POLL_US,
> + CS35L56_HALO_STATE_TIMEOUT_US);
> + if (ret < 0)
> + dev_err(cs35l56->dev, "Failed to poll PM_CUR_STATE to 1 is %d (ret %d)\n",
> + val, ret);
> +
> + /* Use wm_adsp to load and apply the firmware patch and coefficient files */
> + ret = wm_adsp_power_up(&cs35l56->dsp);
> + if (ret) {
> + dev_dbg(cs35l56->dev, "%s: wm_adsp_power_up ret %d\n", __func__, ret);
> + goto err;
> + }
> +
> + if (cs35l56->removing)
> + goto err;
> +
> + mutex_lock(&cs35l56->irq_lock);
> +
> + init_completion(&cs35l56->init_completion);
> +
> + cs35l56_system_reset(cs35l56);
> +
> + if (cs35l56->sdw_peripheral) {
> + if (!wait_for_completion_timeout(&cs35l56->init_completion,
> + msecs_to_jiffies(5000))) {
> + dev_err(cs35l56->dev, "%s: init_completion timed out (SDW)\n", __func__);

shouldn't do the same routine as for a regular pm_runtime resume,
including re-synching regmaps?

> + goto err_unlock;
> + }
> + } else {
> + if (cs35l56_init(cs35l56))
> + goto err_unlock;
> + }
> +
> + cs35l56->fw_patched = true;
> +
> +err_unlock:
> + mutex_unlock(&cs35l56->irq_lock);
> +err:
> + pm_runtime_mark_last_busy(cs35l56->dev);
> + pm_runtime_put_autosuspend(cs35l56->dev);
> +
> + /* Re-enable SoundWire interrupts */
> + if (cs35l56->sdw_peripheral) {
> + cs35l56->sdw_irq_no_unmask = false;
> + sdw_write_no_pm(cs35l56->sdw_peripheral, CS35L56_SDW_GEN_INT_MASK_1,
> + CS35L56_SDW_INT_MASK_CODEC_IRQ);
> + }
> +
> +complete:
> + complete_all(&cs35l56->dsp_ready_completion);
> +}