From 2dea645ffc21f927067e8e35147985887b1a843d Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 28 Nov 2018 13:45:25 +0200 Subject: i2c: acpi: Return error pointers from i2c_acpi_new_device() The caller would like to know the reason why the i2c_acpi_new_device() fails. For example, if adapter is not available, it might be in the future and we would like to re-probe the clients again. But at the same time we would like to bail out if the error seems unrecoverable, such as invalid argument supplied. To achieve this, return error pointer in some cases. Signed-off-by: Andy Shevchenko Reviewed-by: Heikki Krogerus Reviewed-by: Hans de Goede Acked-by: Mika Westerberg Acked-by: Wolfram Sang --- drivers/i2c/i2c-core-acpi.c | 21 +++++++++++++++------ 1 file changed, 15 insertions(+), 6 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c index 32affd3fa8bd..689c0c467e97 100644 --- a/drivers/i2c/i2c-core-acpi.c +++ b/drivers/i2c/i2c-core-acpi.c @@ -386,20 +386,22 @@ struct notifier_block i2c_acpi_notifier = { * * Also see i2c_new_device, which this function calls to create the i2c-client. * - * Returns a pointer to the new i2c-client, or NULL if the adapter is not found. + * Returns a pointer to the new i2c-client, or error pointer in case of failure. + * Specifically, -EPROBE_DEFER is returned if the adapter is not found. */ struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, struct i2c_board_info *info) { struct i2c_acpi_lookup lookup; struct i2c_adapter *adapter; + struct i2c_client *client; struct acpi_device *adev; LIST_HEAD(resource_list); int ret; adev = ACPI_COMPANION(dev); if (!adev) - return NULL; + return ERR_PTR(-EINVAL); memset(&lookup, 0, sizeof(lookup)); lookup.info = info; @@ -408,16 +410,23 @@ struct i2c_client *i2c_acpi_new_device(struct device *dev, int index, ret = acpi_dev_get_resources(adev, &resource_list, i2c_acpi_fill_info, &lookup); + if (ret < 0) + return ERR_PTR(ret); + acpi_dev_free_resource_list(&resource_list); - if (ret < 0 || !info->addr) - return NULL; + if (!info->addr) + return ERR_PTR(-EADDRNOTAVAIL); adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle); if (!adapter) - return NULL; + return ERR_PTR(-EPROBE_DEFER); + + client = i2c_new_device(adapter, info); + if (!client) + return ERR_PTR(-ENODEV); - return i2c_new_device(adapter, info); + return client; } EXPORT_SYMBOL_GPL(i2c_acpi_new_device); -- cgit v1.2.3 From 5f59d6a1109ce6ade2ad0ba2eb09d8011155daaf Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 28 Nov 2018 13:45:28 +0200 Subject: i2c: acpi: Use ACPI_FAILURE instead of !ACPI_SUCCESS Convert to use ACPI_FAILURE instead of !ACPI_SUCCESS. Signed-off-by: Andy Shevchenko Reviewed-by: Heikki Krogerus Reviewed-by: Hans de Goede Acked-by: Mika Westerberg Acked-by: Wolfram Sang --- drivers/i2c/i2c-core-acpi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c index 689c0c467e97..8a88586e0902 100644 --- a/drivers/i2c/i2c-core-acpi.c +++ b/drivers/i2c/i2c-core-acpi.c @@ -65,7 +65,7 @@ static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data) status = acpi_get_handle(lookup->device_handle, sb->resource_source.string_ptr, &lookup->adapter_handle); - if (!ACPI_SUCCESS(status)) + if (ACPI_FAILURE(status)) return 1; info->addr = sb->slave_address; -- cgit v1.2.3 From 0d5102fe85302aa06a3e5fd8e63b09294aed4c48 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Wed, 28 Nov 2018 13:45:29 +0200 Subject: i2c: acpi: Introduce i2c_acpi_get_i2c_resource() helper Besides current two users one more is coming. Definitely makes sense to introduce a helper. No functional change intended. Signed-off-by: Andy Shevchenko Reviewed-by: Heikki Krogerus Reviewed-by: Hans de Goede Acked-by: Mika Westerberg Acked-by: Wolfram Sang --- drivers/i2c/i2c-core-acpi.c | 41 +++++++++++++++++++++++++++++------------ include/linux/acpi.h | 11 +++++++++++ 2 files changed, 40 insertions(+), 12 deletions(-) (limited to 'drivers/i2c') diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c index 8a88586e0902..272800692088 100644 --- a/drivers/i2c/i2c-core-acpi.c +++ b/drivers/i2c/i2c-core-acpi.c @@ -45,6 +45,33 @@ struct i2c_acpi_lookup { u32 min_speed; }; +/** + * i2c_acpi_get_i2c_resource - Gets I2cSerialBus resource if type matches + * @ares: ACPI resource + * @i2c: Pointer to I2cSerialBus resource will be returned here + * + * Checks if the given ACPI resource is of type I2cSerialBus. + * In this case, returns a pointer to it to the caller. + * + * Returns true if resource type is of I2cSerialBus, otherwise false. + */ +bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, + struct acpi_resource_i2c_serialbus **i2c) +{ + struct acpi_resource_i2c_serialbus *sb; + + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) + return false; + + sb = &ares->data.i2c_serial_bus; + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) + return false; + + *i2c = sb; + return true; +} +EXPORT_SYMBOL_GPL(i2c_acpi_get_i2c_resource); + static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data) { struct i2c_acpi_lookup *lookup = data; @@ -52,11 +79,7 @@ static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data) struct acpi_resource_i2c_serialbus *sb; acpi_status status; - if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) - return 1; - - sb = &ares->data.i2c_serial_bus; - if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) + if (info->addr || !i2c_acpi_get_i2c_resource(ares, &sb)) return 1; if (lookup->index != -1 && lookup->n++ != lookup->index) @@ -534,13 +557,7 @@ i2c_acpi_space_handler(u32 function, acpi_physical_address command, goto err; } - if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) { - ret = AE_BAD_PARAMETER; - goto err; - } - - sb = &ares->data.i2c_serial_bus; - if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) { + if (!value64 || !i2c_acpi_get_i2c_resource(ares, &sb)) { ret = AE_BAD_PARAMETER; goto err; } diff --git a/include/linux/acpi.h b/include/linux/acpi.h index ed80f147bd50..6afc6e3c4c5c 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1054,6 +1054,17 @@ static inline int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index) } #endif +#if defined(CONFIG_ACPI) && IS_ENABLED(CONFIG_I2C) +bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, + struct acpi_resource_i2c_serialbus **i2c); +#else +static inline bool i2c_acpi_get_i2c_resource(struct acpi_resource *ares, + struct acpi_resource_i2c_serialbus **i2c) +{ + return false; +} +#endif + /* Device properties */ #ifdef CONFIG_ACPI -- cgit v1.2.3