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
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原文链接：https://blog.csdn.net/smartvxworks/article/details/124353938