drivers/usb/serial/sierra.c
Source file repositories/reference/linux-study-clean/drivers/usb/serial/sierra.c
File Facts
- System
- Linux kernel
- Corpus path
drivers/usb/serial/sierra.c- Extension
.c- Size
- 29929 bytes
- Lines
- 1059
- Domain
- Driver Families
- Bucket
- drivers/usb
- Inferred role
- Driver Families: implementation source
- Status
- source implementation candidate
Why This File Exists
Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.
- Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
- Allocates kernel memory; connect allocation flags and lifetime to context constraints.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
linux/kernel.hlinux/jiffies.hlinux/errno.hlinux/tty.hlinux/slab.hlinux/tty_flip.hlinux/module.hlinux/usb.hlinux/usb/serial.h
Detected Declarations
struct sierra_iface_liststruct sierra_intf_privatestruct sierra_port_privatefunction sierra_set_power_statefunction sierra_vsc_set_nmeafunction sierra_calc_num_portsfunction is_listedfunction sierra_interface_numfunction sierra_probefunction sierra_send_setupfunction sierra_tiocmgetfunction sierra_tiocmsetfunction sierra_release_urbfunction sierra_outdat_callbackfunction sierra_writefunction sierra_indat_callbackfunction sierra_instat_callbackfunction sierra_write_roomfunction sierra_chars_in_bufferfunction sierra_stop_rx_urbsfunction sierra_submit_rx_urbsfunction sierra_closefunction sierra_openfunction sierra_dtr_rtsfunction sierra_startupfunction sierra_releasefunction sierra_port_probefunction sierra_port_removefunction stop_read_write_urbsfunction sierra_suspendfunction sierra_submit_delayed_urbsfunction sierra_resume
Annotated Snippet
struct sierra_iface_list {
const u8 *nums; /* array of interface numbers */
size_t count; /* number of elements in array */
};
struct sierra_intf_private {
spinlock_t susp_lock;
unsigned int suspended:1;
int in_flight;
unsigned int open_ports;
};
static int sierra_set_power_state(struct usb_device *udev, __u16 swiState)
{
return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
SWIMS_USB_REQUEST_SetPower, /* __u8 request */
USB_TYPE_VENDOR, /* __u8 request type */
swiState, /* __u16 value */
0, /* __u16 index */
NULL, /* void *data */
0, /* __u16 size */
USB_CTRL_SET_TIMEOUT); /* int timeout */
}
static int sierra_vsc_set_nmea(struct usb_device *udev, __u16 enable)
{
return usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
SWIMS_USB_REQUEST_SetNmea, /* __u8 request */
USB_TYPE_VENDOR, /* __u8 request type */
enable, /* __u16 value */
0x0000, /* __u16 index */
NULL, /* void *data */
0, /* __u16 size */
USB_CTRL_SET_TIMEOUT); /* int timeout */
}
static int sierra_calc_num_ports(struct usb_serial *serial,
struct usb_serial_endpoints *epds)
{
int num_ports = 0;
u8 ifnum, numendpoints;
ifnum = serial->interface->cur_altsetting->desc.bInterfaceNumber;
numendpoints = serial->interface->cur_altsetting->desc.bNumEndpoints;
/* Dummy interface present on some SKUs should be ignored */
if (ifnum == 0x99)
num_ports = 0;
else if (numendpoints <= 3)
num_ports = 1;
else
num_ports = (numendpoints-1)/2;
return num_ports;
}
static bool is_listed(const u8 ifnum, const struct sierra_iface_list *list)
{
int i;
if (!list)
return false;
for (i = 0; i < list->count; i++) {
if (list->nums[i] == ifnum)
return true;
}
return false;
}
static u8 sierra_interface_num(struct usb_serial *serial)
{
return serial->interface->cur_altsetting->desc.bInterfaceNumber;
}
static int sierra_probe(struct usb_serial *serial,
const struct usb_device_id *id)
{
const struct sierra_iface_list *ignore_list;
int result = 0;
struct usb_device *udev;
u8 ifnum;
udev = serial->dev;
ifnum = sierra_interface_num(serial);
/*
* If this interface supports more than 1 alternate
* select the 2nd one
*/
Annotation
- Immediate include surface: `linux/kernel.h`, `linux/jiffies.h`, `linux/errno.h`, `linux/tty.h`, `linux/slab.h`, `linux/tty_flip.h`, `linux/module.h`, `linux/usb.h`.
- Detected declarations: `struct sierra_iface_list`, `struct sierra_intf_private`, `struct sierra_port_private`, `function sierra_set_power_state`, `function sierra_vsc_set_nmea`, `function sierra_calc_num_ports`, `function is_listed`, `function sierra_interface_num`, `function sierra_probe`, `function sierra_send_setup`.
- Atlas domain: Driver Families / drivers/usb.
- Implementation status: source implementation candidate.
- Synchronization appears in or near this file; preserve lock ordering, sleepability, and interrupt-context constraints.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.