Re: [PATCH v4 1/8] ACPI: scan: Extend acpi_walk_dep_device_list()

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 5/20/21 8:22 PM, Rafael J. Wysocki wrote:
> On Thu, May 20, 2021 at 4:11 PM Daniel Scally <djrscally@gmail.com> wrote:
>>
>> The acpi_walk_dep_device_list() is not as generalisable as its name
>> implies, serving only to decrement the dependency count for each
>> dependent device of the input. Extend the function to instead accept
>> a callback which can be applied to all the dependencies in acpi_dep_list.
>> Replace all existing calls to the function with calls to a wrapper, passing
>> a callback that applies the same dependency reduction.
>>
>> Signed-off-by: Daniel Scally <djrscally@gmail.com>
> 
> LGTM, but I will have changes depending on it.
> 
> If that's fine by Hans, I'll take this one and expose it in a git
> branch that won't be rebased.

Yes that is fine by me, just send me a pull-req when the branch
is ready and I'll merge that into pdx86/for-next.

Regards,

Hans


> 
>> ---
>> changes since v3:
>>
>>         - Most of the functions got renamed
>>         - acpi_dev_get_dependent_dev() was altered to take a struct acpi_device
>>         This had some repurcussions in the other files, mostly switching from
>>         ACPI_HANDLE() to ACPI_COMPANION().
>>         - acpi_walk_dep_device_list() was altered to check the return value of
>>         the callback on each iteration of the loop, to allow for error handling
>>         of the callbacks or breaking the loop early to save time. Andy, Wolfram,
>>         I thought this change was significant enough to drop your R-b and Ack.
>>
>>  drivers/acpi/ec.c                             |  2 +-
>>  drivers/acpi/pmic/intel_pmic_chtdc_ti.c       |  2 +-
>>  drivers/acpi/scan.c                           | 69 ++++++++++++++-----
>>  drivers/gpio/gpiolib-acpi.c                   | 10 +--
>>  drivers/i2c/i2c-core-acpi.c                   |  8 +--
>>  drivers/platform/surface/aggregator/core.c    |  6 +-
>>  drivers/platform/surface/surface3_power.c     | 22 +++---
>>  .../platform/surface/surface_acpi_notify.c    |  7 +-
>>  include/acpi/acpi_bus.h                       |  7 ++
>>  include/linux/acpi.h                          |  4 +-
>>  10 files changed, 90 insertions(+), 47 deletions(-)
>>
>> diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
>> index 13565629ce0a..3f7680a007a3 100644
>> --- a/drivers/acpi/ec.c
>> +++ b/drivers/acpi/ec.c
>> @@ -1627,7 +1627,7 @@ static int acpi_ec_add(struct acpi_device *device)
>>         WARN(!ret, "Could not request EC cmd io port 0x%lx", ec->command_addr);
>>
>>         /* Reprobe devices depending on the EC */
>> -       acpi_walk_dep_device_list(ec->handle);
>> +       acpi_dev_clear_dependencies(device);
>>
>>         acpi_handle_debug(ec->handle, "enumerated.\n");
>>         return 0;
>> diff --git a/drivers/acpi/pmic/intel_pmic_chtdc_ti.c b/drivers/acpi/pmic/intel_pmic_chtdc_ti.c
>> index a5101b07611a..fef7831d0d63 100644
>> --- a/drivers/acpi/pmic/intel_pmic_chtdc_ti.c
>> +++ b/drivers/acpi/pmic/intel_pmic_chtdc_ti.c
>> @@ -117,7 +117,7 @@ static int chtdc_ti_pmic_opregion_probe(struct platform_device *pdev)
>>                 return err;
>>
>>         /* Re-enumerate devices depending on PMIC */
>> -       acpi_walk_dep_device_list(ACPI_HANDLE(pdev->dev.parent));
>> +       acpi_dev_clear_dependencies(ACPI_COMPANION(pdev->dev.parent));
>>         return 0;
>>  }
>>
>> diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
>> index 453eff8ec8c3..195635c3462b 100644
>> --- a/drivers/acpi/scan.c
>> +++ b/drivers/acpi/scan.c
>> @@ -47,12 +47,6 @@ static DEFINE_MUTEX(acpi_hp_context_lock);
>>   */
>>  static u64 spcr_uart_addr;
>>
>> -struct acpi_dep_data {
>> -       struct list_head node;
>> -       acpi_handle supplier;
>> -       acpi_handle consumer;
>> -};
>> -
>>  void acpi_scan_lock_acquire(void)
>>  {
>>         mutex_lock(&acpi_scan_lock);
>> @@ -2111,30 +2105,69 @@ static void acpi_bus_attach(struct acpi_device *device, bool first_pass)
>>                 device->handler->hotplug.notify_online(device);
>>  }
>>
>> -void acpi_walk_dep_device_list(acpi_handle handle)
>> +static int acpi_scan_clear_dep(struct acpi_dep_data *dep, void *data)
>>  {
>> -       struct acpi_dep_data *dep, *tmp;
>>         struct acpi_device *adev;
>>
>> +       acpi_bus_get_device(dep->consumer, &adev);
>> +
>> +       if (adev) {
>> +               adev->dep_unmet--;
>> +               if (!adev->dep_unmet)
>> +                       acpi_bus_attach(adev, true);
>> +       }
>> +
>> +       list_del(&dep->node);
>> +       kfree(dep);
>> +
>> +       return 0;
>> +}
>> +
>> +/**
>> + * acpi_walk_dep_device_list - Apply a callback to every entry in acpi_dep_list
>> + * @handle:    The ACPI handle of the supplier device
>> + * @callback:  Pointer to the callback function to apply
>> + * @data:      Pointer to some data to pass to the callback
>> + *
>> + * The return value of the callback determines this function's behaviour. If 0
>> + * is returned we continue to iterate over acpi_dep_list. If a positive value
>> + * is returned then the loop is broken but this function returns 0. If a
>> + * negative value is returned by the callback then the loop is broken and that
>> + * value is returned as the final error.
>> + */
>> +int acpi_walk_dep_device_list(acpi_handle handle,
>> +                             int (*callback)(struct acpi_dep_data *, void *),
>> +                             void *data)
>> +{
>> +       struct acpi_dep_data *dep, *tmp;
>> +       int ret;
>> +
>>         mutex_lock(&acpi_dep_list_lock);
>>         list_for_each_entry_safe(dep, tmp, &acpi_dep_list, node) {
>>                 if (dep->supplier == handle) {
>> -                       acpi_bus_get_device(dep->consumer, &adev);
>> -
>> -                       if (adev) {
>> -                               adev->dep_unmet--;
>> -                               if (!adev->dep_unmet)
>> -                                       acpi_bus_attach(adev, true);
>> -                       }
>> -
>> -                       list_del(&dep->node);
>> -                       kfree(dep);
>> +                       ret = callback(dep, data);
>> +                       if (ret)
>> +                               break;
>>                 }
>>         }
>>         mutex_unlock(&acpi_dep_list_lock);
>> +
>> +       return ret > 0 ? 0 : ret;
>>  }
>>  EXPORT_SYMBOL_GPL(acpi_walk_dep_device_list);
>>
>> +/**
>> + * acpi_dev_clear_dependencies - Inform consumers that the device is now active
>> + * @supplier: Pointer to the supplier &struct acpi_device
>> + *
>> + * Clear dependencies on the given device.
>> + */
>> +void acpi_dev_clear_dependencies(struct acpi_device *supplier)
>> +{
>> +       acpi_walk_dep_device_list(supplier->handle, acpi_scan_clear_dep, NULL);
>> +}
>> +EXPORT_SYMBOL_GPL(acpi_dev_clear_dependencies);
>> +
>>  /**
>>   * acpi_bus_scan - Add ACPI device node objects in a given namespace scope.
>>   * @handle: Root of the namespace scope to scan.
>> diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c
>> index 3ef22a3c104d..5b4111e4be3f 100644
>> --- a/drivers/gpio/gpiolib-acpi.c
>> +++ b/drivers/gpio/gpiolib-acpi.c
>> @@ -1233,14 +1233,14 @@ static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
>>  void acpi_gpiochip_add(struct gpio_chip *chip)
>>  {
>>         struct acpi_gpio_chip *acpi_gpio;
>> -       acpi_handle handle;
>> +       struct acpi_device *adev;
>>         acpi_status status;
>>
>>         if (!chip || !chip->parent)
>>                 return;
>>
>> -       handle = ACPI_HANDLE(chip->parent);
>> -       if (!handle)
>> +       adev = ACPI_COMPANION(chip->parent);
>> +       if (!adev)
>>                 return;
>>
>>         acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
>> @@ -1254,7 +1254,7 @@ void acpi_gpiochip_add(struct gpio_chip *chip)
>>         INIT_LIST_HEAD(&acpi_gpio->events);
>>         INIT_LIST_HEAD(&acpi_gpio->deferred_req_irqs_list_entry);
>>
>> -       status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
>> +       status = acpi_attach_data(adev->handle, acpi_gpio_chip_dh, acpi_gpio);
>>         if (ACPI_FAILURE(status)) {
>>                 dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
>>                 kfree(acpi_gpio);
>> @@ -1263,7 +1263,7 @@ void acpi_gpiochip_add(struct gpio_chip *chip)
>>
>>         acpi_gpiochip_request_regions(acpi_gpio);
>>         acpi_gpiochip_scan_gpios(acpi_gpio);
>> -       acpi_walk_dep_device_list(handle);
>> +       acpi_dev_clear_dependencies(adev);
>>  }
>>
>>  void acpi_gpiochip_remove(struct gpio_chip *chip)
>> diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
>> index 8ceaa88dd78f..6f0aa0ed3241 100644
>> --- a/drivers/i2c/i2c-core-acpi.c
>> +++ b/drivers/i2c/i2c-core-acpi.c
>> @@ -259,8 +259,8 @@ static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
>>   */
>>  void i2c_acpi_register_devices(struct i2c_adapter *adap)
>>  {
>> +       struct acpi_device *adev;
>>         acpi_status status;
>> -       acpi_handle handle;
>>
>>         if (!has_acpi_companion(&adap->dev))
>>                 return;
>> @@ -275,11 +275,11 @@ void i2c_acpi_register_devices(struct i2c_adapter *adap)
>>         if (!adap->dev.parent)
>>                 return;
>>
>> -       handle = ACPI_HANDLE(adap->dev.parent);
>> -       if (!handle)
>> +       adev = ACPI_COMPANION(adap->dev.parent);
>> +       if (!adev)
>>                 return;
>>
>> -       acpi_walk_dep_device_list(handle);
>> +       acpi_dev_clear_dependencies(adev);
>>  }
>>
>>  static const struct acpi_device_id i2c_acpi_force_400khz_device_ids[] = {
>> diff --git a/drivers/platform/surface/aggregator/core.c b/drivers/platform/surface/aggregator/core.c
>> index 8dc2c267bcd6..517f774a6e60 100644
>> --- a/drivers/platform/surface/aggregator/core.c
>> +++ b/drivers/platform/surface/aggregator/core.c
>> @@ -621,8 +621,8 @@ static const struct acpi_gpio_mapping ssam_acpi_gpios[] = {
>>
>>  static int ssam_serial_hub_probe(struct serdev_device *serdev)
>>  {
>> +       struct acpi_device *ssh = ACPI_COMPANION(&serdev->dev);
>>         struct ssam_controller *ctrl;
>> -       acpi_handle *ssh = ACPI_HANDLE(&serdev->dev);
>>         acpi_status astatus;
>>         int status;
>>
>> @@ -652,7 +652,7 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
>>         if (status)
>>                 goto err_devopen;
>>
>> -       astatus = ssam_serdev_setup_via_acpi(ssh, serdev);
>> +       astatus = ssam_serdev_setup_via_acpi(ssh->handle, serdev);
>>         if (ACPI_FAILURE(astatus)) {
>>                 status = -ENXIO;
>>                 goto err_devinit;
>> @@ -706,7 +706,7 @@ static int ssam_serial_hub_probe(struct serdev_device *serdev)
>>          *       For now let's thus default power/wakeup to false.
>>          */
>>         device_set_wakeup_capable(&serdev->dev, true);
>> -       acpi_walk_dep_device_list(ssh);
>> +       acpi_dev_clear_dependencies(ssh);
>>
>>         return 0;
>>
>> diff --git a/drivers/platform/surface/surface3_power.c b/drivers/platform/surface/surface3_power.c
>> index cc4f9cba6856..dea82aa1abd4 100644
>> --- a/drivers/platform/surface/surface3_power.c
>> +++ b/drivers/platform/surface/surface3_power.c
>> @@ -446,12 +446,12 @@ mshw0011_space_handler(u32 function, acpi_physical_address command,
>>
>>  static int mshw0011_install_space_handler(struct i2c_client *client)
>>  {
>> -       acpi_handle handle;
>> +       struct acpi_device *adev;
>>         struct mshw0011_handler_data *data;
>>         acpi_status status;
>>
>> -       handle = ACPI_HANDLE(&client->dev);
>> -       if (!handle)
>> +       adev = ACPI_COMPANION(&client->dev);
>> +       if (!adev)
>>                 return -ENODEV;
>>
>>         data = kzalloc(sizeof(struct mshw0011_handler_data),
>> @@ -460,25 +460,25 @@ static int mshw0011_install_space_handler(struct i2c_client *client)
>>                 return -ENOMEM;
>>
>>         data->client = client;
>> -       status = acpi_bus_attach_private_data(handle, (void *)data);
>> +       status = acpi_bus_attach_private_data(adev->handle, (void *)data);
>>         if (ACPI_FAILURE(status)) {
>>                 kfree(data);
>>                 return -ENOMEM;
>>         }
>>
>> -       status = acpi_install_address_space_handler(handle,
>> -                               ACPI_ADR_SPACE_GSBUS,
>> -                               &mshw0011_space_handler,
>> -                               NULL,
>> -                               data);
>> +       status = acpi_install_address_space_handler(adev->handle,
>> +                                                   ACPI_ADR_SPACE_GSBUS,
>> +                                                   &mshw0011_space_handler,
>> +                                                   NULL,
>> +                                                   data);
>>         if (ACPI_FAILURE(status)) {
>>                 dev_err(&client->dev, "Error installing i2c space handler\n");
>> -               acpi_bus_detach_private_data(handle);
>> +               acpi_bus_detach_private_data(adev->handle);
>>                 kfree(data);
>>                 return -ENOMEM;
>>         }
>>
>> -       acpi_walk_dep_device_list(handle);
>> +       acpi_dev_clear_dependencies(adev);
>>         return 0;
>>  }
>>
>> diff --git a/drivers/platform/surface/surface_acpi_notify.c b/drivers/platform/surface/surface_acpi_notify.c
>> index ef9c1f8e8336..8339988d95c1 100644
>> --- a/drivers/platform/surface/surface_acpi_notify.c
>> +++ b/drivers/platform/surface/surface_acpi_notify.c
>> @@ -798,7 +798,7 @@ static int san_consumer_links_setup(struct platform_device *pdev)
>>
>>  static int san_probe(struct platform_device *pdev)
>>  {
>> -       acpi_handle san = ACPI_HANDLE(&pdev->dev);
>> +       struct acpi_device *san = ACPI_COMPANION(&pdev->dev);
>>         struct ssam_controller *ctrl;
>>         struct san_data *data;
>>         acpi_status astatus;
>> @@ -821,7 +821,8 @@ static int san_probe(struct platform_device *pdev)
>>
>>         platform_set_drvdata(pdev, data);
>>
>> -       astatus = acpi_install_address_space_handler(san, ACPI_ADR_SPACE_GSBUS,
>> +       astatus = acpi_install_address_space_handler(san->handle,
>> +                                                    ACPI_ADR_SPACE_GSBUS,
>>                                                      &san_opreg_handler, NULL,
>>                                                      &data->info);
>>         if (ACPI_FAILURE(astatus))
>> @@ -835,7 +836,7 @@ static int san_probe(struct platform_device *pdev)
>>         if (status)
>>                 goto err_install_dev;
>>
>> -       acpi_walk_dep_device_list(san);
>> +       acpi_dev_clear_dependencies(san);
>>         return 0;
>>
>>  err_install_dev:
>> diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
>> index 3a82faac5767..0b2c4f170f4d 100644
>> --- a/include/acpi/acpi_bus.h
>> +++ b/include/acpi/acpi_bus.h
>> @@ -280,6 +280,12 @@ struct acpi_device_power {
>>         struct acpi_device_power_state states[ACPI_D_STATE_COUNT];      /* Power states (D0-D3Cold) */
>>  };
>>
>> +struct acpi_dep_data {
>> +       struct list_head node;
>> +       acpi_handle supplier;
>> +       acpi_handle consumer;
>> +};
>> +
>>  /* Performance Management */
>>
>>  struct acpi_device_perf_flags {
>> @@ -685,6 +691,7 @@ static inline bool acpi_device_can_poweroff(struct acpi_device *adev)
>>
>>  bool acpi_dev_hid_uid_match(struct acpi_device *adev, const char *hid2, const char *uid2);
>>
>> +void acpi_dev_clear_dependencies(struct acpi_device *supplier);
>>  struct acpi_device *
>>  acpi_dev_get_next_match_dev(struct acpi_device *adev, const char *hid, const char *uid, s64 hrv);
>>  struct acpi_device *
>> diff --git a/include/linux/acpi.h b/include/linux/acpi.h
>> index c60745f657e9..170b9bebdb2b 100644
>> --- a/include/linux/acpi.h
>> +++ b/include/linux/acpi.h
>> @@ -666,7 +666,9 @@ extern bool acpi_driver_match_device(struct device *dev,
>>                                      const struct device_driver *drv);
>>  int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *);
>>  int acpi_device_modalias(struct device *, char *, int);
>> -void acpi_walk_dep_device_list(acpi_handle handle);
>> +int acpi_walk_dep_device_list(acpi_handle handle,
>> +                             int (*callback)(struct acpi_dep_data *, void *),
>> +                             void *data);
>>
>>  struct platform_device *acpi_create_platform_device(struct acpi_device *,
>>                                                     struct property_entry *);
>> --
>> 2.25.1
>>
>