diff options
Diffstat (limited to 'drivers/net/wireless/iwlwifi/iwl-bus.h')
| -rw-r--r-- | drivers/net/wireless/iwlwifi/iwl-bus.h | 72 |
1 files changed, 59 insertions, 13 deletions
diff --git a/drivers/net/wireless/iwlwifi/iwl-bus.h b/drivers/net/wireless/iwlwifi/iwl-bus.h index 83aed46673e..08b97594e30 100644 --- a/drivers/net/wireless/iwlwifi/iwl-bus.h +++ b/drivers/net/wireless/iwlwifi/iwl-bus.h @@ -63,19 +63,65 @@ #ifndef __iwl_bus_h__ #define __iwl_bus_h__ -/*This file includes the declaration that are exported from the bus layer */ - #include <linux/types.h> #include <linux/spinlock.h> +/** + * DOC: Bus layer - role and goal + * + * iwl-bus.h defines the API to the bus layer of the iwlwifi driver. + * The bus layer is responsible for doing very basic bus operations that are + * listed in the iwl_bus_ops structure. + * The bus layer registers to the bus driver, advertises the supported HW and + * gets notifications about enumeration, suspend, resume. + * For the moment, the bus layer is not a linux kernel module as itself, and + * the module_init function of the driver must call the bus specific + * registration functions. These functions are listed at the end of this file. + * For the moment, there is only one implementation of this interface: PCI-e. + * This implementation is iwl-pci.c + */ + +/** + * DOC: encapsulation and type safety + * + * The iwl_bus describes the data that is shared amongst all the bus layer + * implementations. This data is visible to other layers. Data in the bus + * specific area is not visible outside the bus specific implementation. + * iwl_bus holds a pointer to iwl_shared which holds pointer to all the other + * layers of the driver (iwl_priv, iwl_trans). In fact, this is the way to go + * when the transport layer needs to call a function of another layer. + * + * In order to achieve encapsulation, iwl_priv cannot be dereferenced from the + * bus layer. Type safety is still kept since functions that gets iwl_priv gets + * a typed pointer (as opposed to void *). + */ + +/** + * DOC: probe flow + * + * The module_init calls the bus specific registration function. The + * registration to the bus layer will trigger an enumeration of the bus which + * will call the bus specific probe function. + * The first thing this function must do is to allocate the memory needed by + * iwl_bus + the bus_specific data. + * Once the bus specific probe function has configured the hardware, it + * chooses the appropriate transport layer and calls iwl_probe that will run + * the bus independent probe flow. + * + * Note: The bus specific code must set the following data in iwl_bus before it + * calls iwl_probe: + * * bus->dev + * * bus->irq + * * bus->ops + */ + struct iwl_shared; struct iwl_bus; /** * struct iwl_bus_ops - bus specific operations * @get_pm_support: must returns true if the bus can go to sleep - * @apm_config: will be called during the config of the APM configuration - * @set_drv_data: set the shared data pointer to the bus layer + * @apm_config: will be called during the config of the APM * @get_hw_id: prints the hw_id in the provided buffer * @write8: write a byte to register at offset ofs * @write32: write a dword to register at offset ofs @@ -84,7 +130,6 @@ struct iwl_bus; struct iwl_bus_ops { bool (*get_pm_support)(struct iwl_bus *bus); void (*apm_config)(struct iwl_bus *bus); - void (*set_drv_data)(struct iwl_bus *bus, struct iwl_shared *shrd); void (*get_hw_id)(struct iwl_bus *bus, char buf[], int buf_len); void (*write8)(struct iwl_bus *bus, u32 ofs, u8 val); void (*write32)(struct iwl_bus *bus, u32 ofs, u32 val); @@ -93,14 +138,18 @@ struct iwl_bus_ops { /** * struct iwl_bus - bus common data - * @dev - pointer to struct device * that represent the device + * + * This data is common to all bus layer implementations. + * + * @dev - pointer to struct device * that represents the device * @ops - pointer to iwl_bus_ops * @shrd - pointer to iwl_shared which holds shared data from the upper layer + * NB: for the time being this needs to be set by the upper layer since + * it allocates the shared data * @irq - the irq number for the device * @reg_lock - protect hw register access */ struct iwl_bus { - /* Common data to all buses */ struct device *dev; const struct iwl_bus_ops *ops; struct iwl_shared *shrd; @@ -123,12 +172,6 @@ static inline void bus_apm_config(struct iwl_bus *bus) bus->ops->apm_config(bus); } -static inline void bus_set_drv_data(struct iwl_bus *bus, - struct iwl_shared *shrd) -{ - bus->ops->set_drv_data(bus, shrd); -} - static inline void bus_get_hw_id(struct iwl_bus *bus, char buf[], int buf_len) { bus->ops->get_hw_id(bus, buf, buf_len); @@ -149,6 +192,9 @@ static inline u32 bus_read32(struct iwl_bus *bus, u32 ofs) return bus->ops->read32(bus, ofs); } +/***************************************************** +* Bus layer registration functions +******************************************************/ int __must_check iwl_pci_register_driver(void); void iwl_pci_unregister_driver(void); |