mtk7621驱动

无线驱动在完成驱动注册的同时，需要进行 cfg80211接口注册(提供命令支持)。

1.驱动

mtk wifi驱动基于pci进行扩展，第一个文件：/os/linux/pci_main_dev.c

文件用于创建和注册基于pci接口的网络设备，PCI设备上有三种地址空间：PCI的I/O空间、PCI的存储空间和PCI的配置空间。CPU可以访问PCI设备上的所有地址空间，其中I/O空间和存储空间提供给设备驱动程序使用，而配置空间则由Linux内核中的PCI初始化代码使用。内核在启动时负责对所有PCI设备进行初始化，配置好所有的PCI设备，包括中断号以及I/O基址，并在文件/proc/pci中列出所有找到的PCI设备，以及这些设备的参数和属性。

Linux驱动程序通常使用结构(struct)来表示一种设备，而结构体中的变量则代表某一具体设备，该变量存放了与该设备相关的所有信息。好的驱动程序都应该能驱动多个同种设备，每个设备之间用次设备号进行区分，如果采用结构数据来代表所有能由该驱动程序驱动的设备，那么就可以简单地使用数组下标来表示次设备号。

1.1数据结构

1 static struct pci_device_id rt_pci_tbl[]

DEVINITDATA =

{

{PCI_DEVICE(NIC_PCI_VENDOR_ID,

NIC3091_PCIe_DEVICE_ID)},

#ifdef RT8592

{PCI_DEVICE(NIC_PCI_VENDOR_ID,

NIC8592_PCIe_DEVICE_ID)},

#endif /* RT8592 */

#ifdef MT76x2

{PCI_DEVICE(0x1400, NIC7650_PCIe_DEVICE_ID)},

{PCI_DEVICE(0x1400,

NIC7662_PCIe_DEVICE_ID)},

{PCI_DEVICE(MTK_PCI_VENDOR_ID,

NIC7662_PCIe_DEVICE_ID)},

{PCI_DEVICE(MTK_PCI_VENDOR_ID,

NIC7632_PCIe_DEVICE_ID)},

{PCI_DEVICE(MTK_PCI_VENDOR_ID,

NIC7612_PCIe_DEVICE_ID)},

{PCI_DEVICE(MTK_PCI_VENDOR_ID,

NIC7602_PCIe_DEVICE_ID)},

#endif /* MT76x2 */

{} /* terminate list */

};

struct pci_device_id {

__u32

vendor,device;

//厂商和设备ID

__u32

subvendor,subdevice;          //子系统和设备ID

__u32 class,class_mask;

//类、子类、prog-if三元组

kernel_ulong_t

driver_data;           //驱动私有数据

pci_device_id 用MODULE_DEVICE_TABLE映射到用户空间。

2 struct pci_driver {

struct list_head node;

const char *name;

const struct pci_device_id *id_table; /* must

be non-NULL for probe to be called */

int (*probe) (struct pci_dev *dev, const

struct pci_device_id *id); /* New device inserted */

void (*remove) (struct pci_dev *dev); /*

Device removed (NULL if not a hot-plug capable driver) */

int (*suspend) (struct pci_dev *dev,

pm_message_t state); /* Device suspended */

int (*suspend_late) (struct pci_dev *dev,

pm_message_t state);

int (*resume_early) (struct pci_dev *dev);

int (*resume) (struct pci_dev *dev); /*

Device woken up */

void (*shutdown) (struct pci_dev *dev);

int (*sriov_configure) (struct pci_dev

*dev, int num_vfs); /* PF pdev */

const struct pci_error_handlers

*err_handler;

struct device_driver driver;

struct pci_dynids dynids;

};

3 struct pci_dev {

struct list_head bus_list;

/* 总线设备链表元素bus_list：每一个pci_dev结构除了链接到全局设备链表中外，还会通过这个成员连接到其所属PCI总线的设备链表中。每一条PCI总线都维护一条它自己的设备链表视图，以便描述所有连接在该PCI总线上的设备，其表头由PCI总线的pci_bus结构中的 devices成员所描述t*/

struct pci_bus *bus;

/* 总线指针bus：指向这个PCI设备所在的PCI总线的pci_bus结构。因此，对于桥设备而言，bus指针将指向桥设备的主总线(primary bus)，也即指向桥设备所在的PCI总线*/

struct pci_bus *subordinate;

/* 指针subordinate：指向这个PCI设备所桥接的下级总线。这个指针成员仅对桥设备才有意义，而对于一般的非桥PCI设备而言，该指针成员总是为NULL*/

void *sysdata;

/* 无类型指针sysdata：指向一片特定于系统的扩展数据*/

struct proc_dir_entry *procent;

/* 指针procent：指向该PCI设备在／proc文件系统中对应的目录项*/

unsigned int devfn;

/* devfn：这个PCI设备的设备功能号，也成为PCI逻辑设备号(0－255)。其中bit[7:3]是物理设备号(取值范围0－31)，bit[2:0]是功能号(取值范围0－7)。 */

unsigned short vendor;

/* vendor：这是一个16无符号整数，表示PCI设备的厂商ID*/

unsigned short device;

/*device：这是一个16无符号整数，表示PCI设备的设备ID */

unsigned short subsystem_vendor;

/* subsystem_vendor：这是一个16无符号整数，表示PCI设备的子系统厂商ID*/

unsigned short subsystem_device;

/* subsystem_device：这是一个16无符号整数，表示PCI设备的子系统设备ID。*/

unsigned int class;

/* class：32位的无符号整数，表示该PCI设备的类别，其中，bit［7：0］为编程接口，bit［15：8］为子类别代码，bit ［23：16］为基类别代码，bit［31：24］无意义。显然，class成员的低3字节刚好对应与PCI配置空间中的类代码*/

u8 revision; /* PCI revision, low byte of

class word */

u8 hdr_type; /* PCI header type (`multi'

flag masked out) */

u8 pcie_cap; /* PCI-E capability offset */

u8 msi_cap; /* MSI capability offset */

u8 msix_cap; /* MSI-X capability offset */

u8 pcie_mpss:3; /* PCI-E Max Payload Size

Supported */

u8 rom_base_reg; /* which config register

controls the ROM */

u8 pin; /* which interrupt pin this device

uses */

u16 pcie_flags_reg; /* cached PCI-E

Capabilities Register */

struct pci_driver *driver;

/* 指针driver：指向这个PCI设备所对应的驱动程序定义的pci_driver结构。每一个pci设备驱动程序都必须定义它自己的pci_driver结构来描述它自己。*/

u64 dma_mask;

/*dma_mask：用于DMA的总线地址掩码，一般来说，这个成员的值是0xffffffff。数据类型dma_addr_t定义在include/asm/types.h中，在x86平台上，dma_addr_t类型就是u32类型*/

struct device_dma_parameters dma_parms;

pci_power_t current_state;

/* 当前操作状态 */

u8 pm_cap; /* PM capability offset */

unsigned int pme_support:5; /* Bitmask of

states from which PME#

can be generated */

unsigned int pme_interrupt:1;

unsigned int pme_poll:1; /* Poll device's

PME status bit */

unsigned int d1_support:1; /* Low power

state D1 is supported */

unsigned int d2_support:1; /* Low power

state D2 is supported */

unsigned int no_d1d2:1; /* D1 and D2 are

forbidden */

unsigned int no_d3cold:1; /* D3cold is

forbidden */

unsigned int d3cold_allowed:1; /* D3cold

is allowed by user */

unsigned int mmio_always_on:1; /* disallow

turning off io/mem

decoding during bar sizing */

unsigned int wakeup_prepared:1;

unsigned int runtime_d3cold:1; /* whether

go through runtime

D3cold, not set for devices

powered on/off by the

corresponding bridge */

unsigned int d3_delay; /* D3->D0

transition time in ms */

unsigned int d3cold_delay; /*

D3cold->D0 transition time in ms */

pci_channel_state_t error_state; /*

current connectivity state */

struct device dev; /* Generic device

interface */

int cfg_size;

/* 配置空间的大小 */

unsigned int irq;

struct resource

resource[DEVICE_COUNT_RESOURCE]; /* I/O and memory regions + expansion ROMs */

bool match_driver; /* Skip attaching

driver */

/* These fields are used by common fixups

*/

unsigned int transparent:1; /* Transparent

PCI bridge */

unsigned int multifunction:1;/* Part of

multi-function device */

/* keep track of device state */

unsigned int is_added:1;

unsigned int is_busmaster:1; /* device is

busmaster */

unsigned int no_msi:1; /* device may not

use msi */

unsigned int block_cfg_access:1; /* config

space access is blocked */

unsigned int broken_parity_status:1; /*

Device generates false positive parity */

unsigned int irq_reroute_variant:2; /*

device needs IRQ rerouting variant */

unsigned int msi_enabled:1;

unsigned int msix_enabled:1;

unsigned int ari_enabled:1; /* ARI

forwarding */

unsigned int is_managed:1;

unsigned int is_pcie:1; /* Obsolete. Will

be removed.

Use pci_is_pcie() instead */

unsigned int needs_freset:1; /* Dev

requires fundamental reset */

unsigned int state_saved:1;

unsigned int is_physfn:1;

unsigned int is_virtfn:1;

unsigned int reset_fn:1;

unsigned int is_hotplug_bridge:1;

unsigned int __aer_firmware_first_valid:1;

unsigned int __aer_firmware_first:1;

unsigned int broken_intx_masking:1;

unsigned int io_window_1k:1; /* Intel P2P

bridge 1K I/O windows */

pci_dev_flags_t dev_flags;

atomic_t enable_cnt; /* pci_enable_device

has been called */

u32 saved_config_space[16]; /* config

space saved at suspend time */

struct hlist_head saved_cap_space;

struct bin_attribute *rom_attr; /*

attribute descriptor for sysfs ROM entry */

int rom_attr_enabled; /* has display of

the rom attribute been enabled? */

struct bin_attribute

*res_attr[DEVICE_COUNT_RESOURCE]; /* sysfs file for resources */

struct bin_attribute

*res_attr_wc[DEVICE_COUNT_RESOURCE]; /* sysfs file for WC mapping of resources

*/

#ifdef CONFIG_PCI_MSI

struct list_head msi_list;

struct kset *msi_kset;

#endif

struct pci_vpd *vpd;

#ifdef CONFIG_PCI_ATS

union {

struct pci_sriov *sriov; /* SR-IOV

capability related */

struct pci_dev *physfn; /* the PF this VF

is associated with */

};

struct pci_ats *ats; /* Address

Translation Service */

#endif

phys_addr_t rom; /* Physical address of

ROM if it's not from the BAR */

size_t romlen; /* Length of ROM if it's

not from the BAR

};

1.2关键函数

1.2.1 rt_pci_init_module

调用函数pci_register_driver(&rt_pci_driver); 注册设备

1.2.2 rt_pci_probe

主要函数分析

1 rv = pci_enable_device(pdev)

唤醒和使能设备

2 rv = pci_request_regions(pdev,

print_name)

函数通知内核，当前PCI将使用这些内存地址，其他设备不能再使用了

3 csr_addr = (unsigned long)

ioremap(pci_resource_start(pdev, 0), pci_resource_len(pdev, 0));

物理地址与虚拟地址进行映射

4 pci_set_master(pdev);

设置设备具有获得总线的能力，即调用这个函数，使设备具备申请使用PCI总线的能力

5 rv = RTMPAllocAdapterBlock(handle,

&pAd);

适配器申请内存， 并进行初始化。(包括beaconbuf申请\rx ring \tx ring 等初始化)。

6 RTMP_DRIVER_PCI_CSR_SET(pAd, csr_addr);

设置pci 对应的虚拟地址映射

7 RTMP_DRIVER_PCIE_INIT(pAd, pdev);

设置wlan芯片相关寄存器设置 以及pcie的初始化,调用mac目录下的接口函数，对寄存器进行设置.

8 net_dev = RtmpPhyNetDevInit(pAd,

&netDevHook);

实现物理层网络设备的创建、初始化、以及相关结构接口的初始化，主要是结构体的创建。

9 CFG80211_Register(pAd,

&(pdev->dev), net_dev);

实现cfg80211网络设备模块的注册, 提供设备cfg80211接口命令：

os/linux/cfg80211/cfg80211.c

struct cfg80211_ops CFG80211_Ops = {

#if (LINUX_VERSION_CODE < KERNEL_VERSION(3,4,0))

.set_beacon = CFG80211_OpsSetBeacon,

.add_beacon = CFG80211_OpsAddBeacon,

.del_beacon = CFG80211_OpsDelBeacon,

#else

.start_ap     =

CFG80211_OpsStartAp,

.change_beacon = CFG80211_OpsChangeBeacon,

.stop_ap     =

CFG80211_OpsStopAp,

#endif /* LINUX_VERSION_CODE 3.4 */

/* set channel for a given wireless

interface */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,6,0))

//.set_monitor_channel =

CFG80211_OpsMonitorChannelSet,

#else

.set_channel      =

CFG80211_OpsChannelSet,

#endif /* LINUX_VERSION_CODE: 3.6.0 */

/* change type/configuration of virtual

interface */

.change_virtual_intf =

CFG80211_OpsVirtualInfChg,

.add_virtual_intf

= CFG80211_OpsVirtualInfAdd,

.del_virtual_intf

= CFG80211_OpsVirtualInfDel,

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,6,0))

.start_p2p_device =

CFG80211_start_p2p_device,

.stop_p2p_device =

CFG80211_stop_p2p_device,

#endif /* LINUX_VERSION_CODE: 3.6.0 */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,30))

/* request to do a scan */

/*

Note: must exist whatever AP or STA

mode; Or your kernel will crash

in v2.6.38.

*/

.scan = CFG80211_OpsScan,

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,31))

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,32))

/* set the transmit power according to

the parameters */

.set_tx_power = CFG80211_OpsTxPwrSet,

/* store the current TX power into the

dbm variable */

.get_tx_power = CFG80211_OpsTxPwrGet,

/* configure WLAN power management */

.set_power_mgmt = CFG80211_OpsPwrMgmt,

/* get station information for the

station identified by @mac */

.get_station = CFG80211_OpsStaGet,

/* dump station callback */

.dump_station = CFG80211_OpsStaDump,

/* notify that wiphy parameters have

changed */

.set_wiphy_params =

CFG80211_OpsWiphyParamsSet,

/* add a key with the given parameters

*/

.add_key = CFG80211_OpsKeyAdd,

/* get information about the key with

the given parameters */

.get_key = CFG80211_OpsKeyGet,

/* remove a key given the @mac_addr */

.del_key = CFG80211_OpsKeyDel,

/* set the default key on an interface

*/

.set_default_key =

CFG80211_OpsKeyDefaultSet,

#ifdef DOT11W_PMF_SUPPORT

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,10,0))

.set_default_mgmt_key =

CFG80211_OpsMgmtKeyDefaultSet,

#endif /* LINUX_VERSION_CODE */

#endif /* DOT11W_PMF_SUPPORT */

/* connect to the ESS with the specified

parameters */

.connect = CFG80211_OpsConnect,

/* disconnect from the BSS/ESS */

.disconnect = CFG80211_OpsDisconnect,

#endif /* LINUX_VERSION_CODE */

#ifdef RFKILL_HW_SUPPORT

/* polls the hw rfkill line */

.rfkill_poll = CFG80211_OpsRFKill,

#endif /* RFKILL_HW_SUPPORT */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,33))

/* get site survey information */

//.dump_survey = CFG80211_OpsSurveyGet,

/* cache a PMKID for a BSSID */

.set_pmksa = CFG80211_OpsPmksaSet,

/* delete a cached PMKID */

.del_pmksa = CFG80211_OpsPmksaDel,

/* flush all cached PMKIDs */

.flush_pmksa = CFG80211_OpsPmksaFlush,

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,34))

/*

Request the driver to remain awake on

the specified

channel for the specified duration to

complete an off-channel

operation (e.g., public action frame exchange).

*/

.remain_on_channel =

CFG80211_OpsRemainOnChannel,

/* cancel an on-going remain-on-channel

operation */

.cancel_remain_on_channel =

CFG80211_OpsCancelRemainOnChannel,

#if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37))

/* transmit an action frame */

.action = NULL,

#else

.mgmt_tx

= CFG80211_OpsMgmtTx,

#endif /* LINUX_VERSION_CODE */

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,38))

.mgmt_tx_cancel_wait

= CFG80211_OpsTxCancelWait,

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,35))

/* configure connection quality monitor

RSSI threshold */

.set_cqm_rssi_config = NULL,

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,37))

/* notify driver that a management frame

type was registered */

.mgmt_frame_register =

CFG80211_OpsMgmtFrameRegister,

#endif /* LINUX_VERSION_CODE */

#if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,38))

/* set antenna configuration (tx_ant,

rx_ant) on the device */

.set_antenna = NULL,

/* get current antenna configuration

from device (tx_ant, rx_ant) */

.get_antenna = NULL,

#endif /* LINUX_VERSION_CODE */

.change_bss

=

CFG80211_OpsChangeBss,

.del_station

=

CFG80211_OpsStaDel,

.add_station

=

CFG80211_OpsStaAdd,

.change_station

=

CFG80211_OpsStaChg,

// .set_bitrate_mask

= CFG80211_OpsBitrateSet,

#ifdef CONFIG_NL80211_TESTMODE

.testmode_cmd

=

CFG80211_OpsTestModeCmd,

#endif /* CONFIG_NL80211_TESTMODE */

};

10 RTMP_DRIVER_OP_MODE_GET(pAd,

&OpMode);

获取当前设备wlan设备的工作模式

11 rv = RtmpOSNetDevAttach(OpMode,

net_dev, &netDevHook);

实现网络设备相应回调函数的初始化以及网络设备的注册

12 RtmpOSNetDevAddrSet(OpMode, net_dev,

&mac_addr[0], NULL);

设置网络设备的mac地址

注释： 一般调用ioctl接口实现一些相关命令处理，函数接口 RTMP_COM_IoctlHandle()

位置/src/common/comm_cfg.c文件

1.2.3 rt_pci_resume

驱动唤醒时调用函数.

1 调用函数rt28xx_open，调用函数进行网络设备相关初始化