Finding Device driver source code

[adam2016]

Hi guys,

I'm using a 64 bit Debian system(ubuntu). I have a wireless card plugged into my computer, I want to get the module of the plugged in wireless adapter, in turn which will allow me or help(hopefully) me find the source code of the driver.

When I installed Ubuntu and plugged in said wireless card it worked right out the gate, so I'm assuming that the driver/module was already installed in the kernel without me needing to add the module.

So my question is, is there anyway to find which module is running my wireless card and in essence how would I then find the source code of the driver?

Bare in mind I'm a relatively new Linux user but want to sift through the code just to get even a glimpse of what's going on even though I probably won't understand a mere line of code.

Thanks

[dutch]

Try sudo lshw -C network as described here:
https://askubuntu.com/questions/333424/how-can-i-check-the-information-of-currently-installed-wifi-drivers

I was able to find my wireless device driver source code in a couple of minutes using that answer.

You probably need to read up on driver modules in linux to understand the structure of the driver, which may not have a main function, but some other set of functions to interface with the operating system as a loadable module:

https://www.apriorit.com/dev-blog/195-simple-driver-for-linux-os

https://www.oreilly.com/library/view/linux-device-drivers/0596005903/ch01.html

https://tldp.org/LDP/tlk/dd/drivers.html

Found this in hw.h in my driver's source code:

/* Function pointers for the MAC. */
struct e1000_mac_operations {
	s32  (*id_led_init)(struct e1000_hw *);
	s32  (*blink_led)(struct e1000_hw *);
	bool (*check_mng_mode)(struct e1000_hw *);
	s32  (*check_for_link)(struct e1000_hw *);
	s32  (*cleanup_led)(struct e1000_hw *);
	void (*clear_hw_cntrs)(struct e1000_hw *);
	void (*clear_vfta)(struct e1000_hw *);
	s32  (*get_bus_info)(struct e1000_hw *);
	void (*set_lan_id)(struct e1000_hw *);
	s32  (*get_link_up_info)(struct e1000_hw *, u16 *, u16 *);
	s32  (*led_on)(struct e1000_hw *);
	s32  (*led_off)(struct e1000_hw *);
	void (*update_mc_addr_list)(struct e1000_hw *, u8 *, u32);
	s32  (*reset_hw)(struct e1000_hw *);
	s32  (*init_hw)(struct e1000_hw *);
	s32  (*setup_link)(struct e1000_hw *);
	s32  (*setup_physical_interface)(struct e1000_hw *);
	s32  (*setup_led)(struct e1000_hw *);
	void (*write_vfta)(struct e1000_hw *, u32, u32);
	void (*config_collision_dist)(struct e1000_hw *);
	int  (*rar_set)(struct e1000_hw *, u8 *, u32);
	s32  (*read_mac_addr)(struct e1000_hw *);
	u32  (*rar_get_count)(struct e1000_hw *);
};

/* When to use various PHY register access functions:
 *
 *                 Func   Caller
 *   Function      Does   Does    When to use
 *   ~~~~~~~~~~~~  ~~~~~  ~~~~~~  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *   X_reg         L,P,A  n/a     for simple PHY reg accesses
 *   X_reg_locked  P,A    L       for multiple accesses of different regs
 *                                on different pages
 *   X_reg_page    A      L,P     for multiple accesses of different regs
 *                                on the same page
 *
 * Where X=[read|write], L=locking, P=sets page, A=register access
 *
 */
struct e1000_phy_operations {
	s32  (*acquire)(struct e1000_hw *);
	s32  (*cfg_on_link_up)(struct e1000_hw *);
	s32  (*check_polarity)(struct e1000_hw *);
	s32  (*check_reset_block)(struct e1000_hw *);
	s32  (*commit)(struct e1000_hw *);
	s32  (*force_speed_duplex)(struct e1000_hw *);
	s32  (*get_cfg_done)(struct e1000_hw *hw);
	s32  (*get_cable_length)(struct e1000_hw *);
	s32  (*get_info)(struct e1000_hw *);
	s32  (*set_page)(struct e1000_hw *, u16);
	s32  (*read_reg)(struct e1000_hw *, u32, u16 *);
	s32  (*read_reg_locked)(struct e1000_hw *, u32, u16 *);
	s32  (*read_reg_page)(struct e1000_hw *, u32, u16 *);
	void (*release)(struct e1000_hw *);
	s32  (*reset)(struct e1000_hw *);
	s32  (*set_d0_lplu_state)(struct e1000_hw *, bool);
	s32  (*set_d3_lplu_state)(struct e1000_hw *, bool);
	s32  (*write_reg)(struct e1000_hw *, u32, u16);
	s32  (*write_reg_locked)(struct e1000_hw *, u32, u16);
	s32  (*write_reg_page)(struct e1000_hw *, u32, u16);
	void (*power_up)(struct e1000_hw *);
	void (*power_down)(struct e1000_hw *);
};

/* Function pointers for the NVM. */
struct e1000_nvm_operations {
	s32  (*acquire)(struct e1000_hw *);
	s32  (*read)(struct e1000_hw *, u16, u16, u16 *);
	void (*release)(struct e1000_hw *);
	void (*reload)(struct e1000_hw *);
	s32  (*update)(struct e1000_hw *);
	s32  (*valid_led_default)(struct e1000_hw *, u16 *);
	s32  (*validate)(struct e1000_hw *);
	s32  (*write)(struct e1000_hw *, u16, u16, u16 *);
};

[adam2016]

Thanks Dutch, just the answer I was looking for :)

Have you ever written or ever needed to actually write a driver in your programming tenure?

I'm going to try find it, I'll update when I find it.

[dutch]

Have you ever written or ever needed to actually write a driver in your programming tenure?

No, never. They're very interesting, though. They form the interface between the hardware and the operating system.