> +static int cs42l43_sdw_update_status(struct sdw_slave *sdw, enum sdw_slave_status status) > +{ > + struct cs42l43 *cs42l43 = dev_get_drvdata(&sdw->dev); > + > + switch (status) { > + case SDW_SLAVE_ATTACHED: > + dev_dbg(cs42l43->dev, "Device attach\n"); > + > + sdw_write_no_pm(sdw, CS42L43_GEN_INT_MASK_1, > + CS42L43_INT_STAT_GEN1_MASK); > + > + cs42l43->attached = true; > + > + complete(&cs42l43->device_attach); > + break; > + case SDW_SLAVE_UNATTACHED: > + dev_dbg(cs42l43->dev, "Device detach\n"); > + > + cs42l43->attached = false; > + > + reinit_completion(&cs42l43->device_attach); > + complete(&cs42l43->device_detach); > + break; > + default: > + break; > + } > + > + return 0; > +} > + > +static int cs42l43_sdw_interrupt(struct sdw_slave *sdw, > + struct sdw_slave_intr_status *status) > +{ > + /* > + * There is only a single bit in GEN_INT_STAT_1 and it doesn't clear if > + * IRQs are still pending so doing a read/write here after handling the > + * IRQ is fine. > + */ > + sdw_read_no_pm(sdw, CS42L43_GEN_INT_STAT_1); > + sdw_write_no_pm(sdw, CS42L43_GEN_INT_STAT_1, 1); > + > + return 0; > +} not really getting the comment and code above. Where is the IRQ handled? In the 'other non-SoundWire part"? > +static void cs42l43_boot_work(struct work_struct *work) > +{ > + struct cs42l43 *cs42l43 = container_of(work, struct cs42l43, boot_work); > + unsigned int devid, revid, otp; > + int ret; > + > + dev_dbg(cs42l43->dev, "Boot work running\n"); > + > + ret = cs42l43_wait_for_attach(cs42l43); > + if (ret) > + goto err; > + > + if (cs42l43->sdw) > + cs42l43->irq = cs42l43->sdw->irq; > + > + ret = regmap_read(cs42l43->regmap, CS42L43_DEVID, &devid); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to read devid: %d\n", ret); > + goto err; > + } > + > + switch (devid) { > + case 0x42a43: > + break; > + default: > + dev_err(cs42l43->dev, "Unrecognised devid: 0x%06x\n", devid); > + goto err; > + } > + > + ret = regmap_read(cs42l43->regmap, CS42L43_REVID, &revid); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to read rev: %d\n", ret); > + goto err; > + } > + > + ret = regmap_read(cs42l43->regmap, CS42L43_OTP_REVISION_ID, &otp); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to read otp rev: %d\n", ret); > + goto err; > + } > + > + dev_info(cs42l43->dev, > + "devid: 0x%06x, rev: 0x%02x, otp: 0x%02x\n", devid, revid, otp); > + > + ret = cs42l43_mcu_update(cs42l43); > + if (ret) > + goto err; > + > + ret = regmap_register_patch(cs42l43->regmap, cs42l43_reva_patch, > + ARRAY_SIZE(cs42l43_reva_patch)); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to apply register patch: %d\n", ret); > + goto err; > + } > + > + pm_runtime_mark_last_busy(cs42l43->dev); > + pm_runtime_put_autosuspend(cs42l43->dev); any reason why the two pm_runtime routines are not placed last, just before the return? > + ret = devm_mfd_add_devices(cs42l43->dev, PLATFORM_DEVID_NONE, > + cs42l43_devs, ARRAY_SIZE(cs42l43_devs), > + NULL, 0, NULL); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to add subdevices: %d\n", ret); > + goto err; > + } > + > + dev_dbg(cs42l43->dev, "Successfully initialised\n"); > + > + return; > + > +err: > + pm_runtime_put_sync(cs42l43->dev); > + cs42l43_dev_remove(cs42l43); > +} > +int cs42l43_dev_probe(struct cs42l43 *cs42l43) > +{ > + int i, ret; > + > + dev_set_drvdata(cs42l43->dev, cs42l43); > + > + mutex_init(&cs42l43->pll_lock); > + init_completion(&cs42l43->device_attach); > + init_completion(&cs42l43->device_detach); > + init_completion(&cs42l43->firmware_download); > + INIT_WORK(&cs42l43->boot_work, cs42l43_boot_work); > + > + regcache_cache_only(cs42l43->regmap, true); > + > + cs42l43->reset = devm_gpiod_get_optional(cs42l43->dev, "reset", GPIOD_OUT_LOW); > + if (IS_ERR(cs42l43->reset)) { > + ret = PTR_ERR(cs42l43->reset); > + dev_err(cs42l43->dev, "Failed to get reset: %d\n", ret); > + return ret; > + } > + > + cs42l43->vdd_p = devm_regulator_get(cs42l43->dev, "VDD_P"); > + if (IS_ERR(cs42l43->vdd_p)) { > + ret = PTR_ERR(cs42l43->vdd_p); > + dev_err(cs42l43->dev, "Failed to get VDD_P: %d\n", ret); > + return ret; > + } > + > + cs42l43->vdd_d = devm_regulator_get(cs42l43->dev, "VDD_D"); > + if (IS_ERR(cs42l43->vdd_d)) { > + ret = PTR_ERR(cs42l43->vdd_d); > + dev_err(cs42l43->dev, "Failed to get VDD_D: %d\n", ret); > + return ret; > + } > + > + BUILD_BUG_ON(ARRAY_SIZE(cs42l43_core_supplies) != CS42L43_N_SUPPLIES); > + > + for (i = 0; i < CS42L43_N_SUPPLIES; i++) > + cs42l43->core_supplies[i].supply = cs42l43_core_supplies[i]; > + > + ret = devm_regulator_bulk_get(cs42l43->dev, CS42L43_N_SUPPLIES, > + cs42l43->core_supplies); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to get core supplies: %d\n", ret); > + return ret; > + } > + > + ret = cs42l43_power_up(cs42l43); > + if (ret) > + return ret; > + > + pm_runtime_set_autosuspend_delay(cs42l43->dev, 250); > + pm_runtime_use_autosuspend(cs42l43->dev); > + pm_runtime_set_active(cs42l43->dev);> + pm_runtime_get_noresume(cs42l43->dev); you probably want a comment to explain that the get_noresume() is intentional to prevent the device from suspending before the workqueue is handled. > + pm_runtime_enable(cs42l43->dev); > + > + queue_work(system_long_wq, &cs42l43->boot_work); > + > + return 0; > +} > +EXPORT_SYMBOL_NS_GPL(cs42l43_dev_probe, MFD_CS42L43); > +static int __maybe_unused cs42l43_suspend(struct device *dev) > +{ > + struct cs42l43 *cs42l43 = dev_get_drvdata(dev); > + int ret; > + > + dev_dbg(cs42l43->dev, "System suspend\n"); > + > + /* > + * Don't care about being resumed here, but we do want force_resume to > + * always trigger an actual resume, so that register state for the > + * MCU/GPIOs is returned as soon as possible after system resume > + */ > + pm_runtime_get_noresume(dev); > + > + ret = pm_runtime_force_suspend(dev); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to force suspend: %d\n", ret); > + return ret; > + } > + > + pm_runtime_put_noidle(dev); Is the get_noresume/put_noidle useful here? What does it do? And it seems wrong anyways, if pm_runtime_force_suspend() fails then the usage-count is not decreased. Surprising sequence... > + > + ret = cs42l43_power_down(cs42l43); > + if (ret) > + return ret; > + > + return 0; > +} > + > +static int __maybe_unused cs42l43_resume(struct device *dev) > +{ > + struct cs42l43 *cs42l43 = dev_get_drvdata(dev); > + int ret; > + > + dev_dbg(cs42l43->dev, "System resume\n"); > + > + ret = cs42l43_power_up(cs42l43); > + if (ret) > + return ret; > + > + ret = pm_runtime_force_resume(dev); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to force resume: %d\n", ret); > + return ret; > + } > + > + return 0; > +} > + > +static int __maybe_unused cs42l43_runtime_suspend(struct device *dev) > +{ > + struct cs42l43 *cs42l43 = dev_get_drvdata(dev); > + > + dev_dbg(cs42l43->dev, "Runtime suspend\n"); > + > + /* > + * Whilst we don't power the chip down here, going into runtime > + * suspend lets the SoundWire bus power down, which means we can't > + * communicate with the device any more. > + */ > + regcache_cache_only(cs42l43->regmap, true); > + > + return 0; > +} > + > +static int __maybe_unused cs42l43_runtime_resume(struct device *dev) > +{ > + struct cs42l43 *cs42l43 = dev_get_drvdata(dev); > + unsigned int reset_canary; > + int ret; > + > + dev_dbg(cs42l43->dev, "Runtime resume\n"); > + > + ret = cs42l43_wait_for_attach(cs42l43); is there a specific reason why the existing initialization_complete is not used? > + if (ret) > + return ret; > + > + ret = regmap_read(cs42l43->regmap, CS42L43_RELID, &reset_canary); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to check reset canary: %d\n", ret); > + goto err; > + } > + > + if (!reset_canary) { > + /* > + * If the canary has cleared the chip has reset, re-handle the > + * MCU and mark the cache as dirty to indicate the chip reset. > + */ > + ret = cs42l43_mcu_update(cs42l43); > + if (ret) > + goto err; > + > + regcache_mark_dirty(cs42l43->regmap); > + } > + > + ret = regcache_sync(cs42l43->regmap); > + if (ret) { > + dev_err(cs42l43->dev, "Failed to restore register cache: %d\n", ret); > + goto err; > + } > + > + return 0; > + > +err: > + regcache_cache_only(cs42l43->regmap, true); > + > + return ret; > +}