drivers/char/toshiba.c

File Facts

System

Linux kernel

Corpus path

drivers/char/toshiba.c

Extension

.c

Size

12740 bytes

Lines

521

Domain

Driver Families

Bucket

drivers/char

Inferred role

Driver Families: operation-table or driver-model contract

Status

pattern 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.
• Defines an operation table; this is where Linux turns generic core objects into subsystem-specific behavior.
• Touches user memory; correctness depends on fault-safe copying and privilege boundary handling.
• Uses kernel synchronization; read lock ordering, sleepability, and interrupt context assumptions before translating.
• Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.

Dependency Surface

• linux/module.h
• linux/kernel.h
• linux/types.h
• linux/fcntl.h
• linux/miscdevice.h
• linux/ioport.h
• asm/io.h
• linux/uaccess.h
• linux/init.h
• linux/stat.h
• linux/proc_fs.h
• linux/seq_file.h
• linux/mutex.h
• linux/toshiba.h

Detected Declarations

• function tosh_fn_status
• function tosh_emulate_fan
• function tosh_smm
• function tosh_ioctl
• function proc_toshiba_show
• function tosh_set_fn_port
• function tosh_get_machine_id
• function tosh_probe
• function toshiba_init
• function toshiba_exit
• module init toshiba_init
• export tosh_smm

Annotated Snippet

static const struct file_operations tosh_fops = {
	.owner		= THIS_MODULE,
	.unlocked_ioctl	= tosh_ioctl,
	.llseek		= noop_llseek,
};

static struct miscdevice tosh_device = {
	TOSH_MINOR_DEV,
	"toshiba",
	&tosh_fops
};

/*
 * Read the Fn key status
 */
#ifdef CONFIG_PROC_FS
static int tosh_fn_status(void)
{
        unsigned char scan;
	unsigned long flags;

	if (tosh_fn!=0) {
		scan = inb(tosh_fn);
	} else {
		local_irq_save(flags);
		outb(0x8e, 0xe4);
		scan = inb(0xe5);
		local_irq_restore(flags);
	}

        return (int) scan;
}
#endif


/*
 * For the Portage 610CT and the Tecra 700CS/700CDT emulate the HCI fan function
 */
static int tosh_emulate_fan(SMMRegisters *regs)
{
	unsigned long eax,ecx,flags;
	unsigned char al;

	eax = regs->eax & 0xff00;
	ecx = regs->ecx & 0xffff;

	/* Portage 610CT */

	if (tosh_id==0xfccb) {
		if (eax==0xfe00) {
			/* fan status */
			local_irq_save(flags);
			outb(0xbe, 0xe4);
			al = inb(0xe5);
			local_irq_restore(flags);
			regs->eax = 0x00;
			regs->ecx = (unsigned int) (al & 0x01);
		}
		if ((eax==0xff00) && (ecx==0x0000)) {
			/* fan off */
			local_irq_save(flags);
			outb(0xbe, 0xe4);
			al = inb(0xe5);
			outb(0xbe, 0xe4);
			outb (al | 0x01, 0xe5);
			local_irq_restore(flags);
			regs->eax = 0x00;
			regs->ecx = 0x00;
		}
		if ((eax==0xff00) && (ecx==0x0001)) {
			/* fan on */
			local_irq_save(flags);
			outb(0xbe, 0xe4);
			al = inb(0xe5);
			outb(0xbe, 0xe4);
			outb(al & 0xfe, 0xe5);
			local_irq_restore(flags);
			regs->eax = 0x00;
			regs->ecx = 0x01;
		}
	}

	/* Tecra 700CS/CDT */

	if (tosh_id==0xfccc) {
		if (eax==0xfe00) {
			/* fan status */
			local_irq_save(flags);
			outb(0xe0, 0xe4);
			al = inb(0xe5);

Annotation

• Immediate include surface: `linux/module.h`, `linux/kernel.h`, `linux/types.h`, `linux/fcntl.h`, `linux/miscdevice.h`, `linux/ioport.h`, `asm/io.h`, `linux/uaccess.h`.
• Detected declarations: `function tosh_fn_status`, `function tosh_emulate_fan`, `function tosh_smm`, `function tosh_ioctl`, `function proc_toshiba_show`, `function tosh_set_fn_port`, `function tosh_get_machine_id`, `function tosh_probe`, `function toshiba_init`, `function toshiba_exit`.
• Atlas domain: Driver Families / drivers/char.
• Implementation status: pattern implementation candidate.
• This snippet crosses the user/kernel memory boundary; validate fault handling and access checks before translating the pattern.
• 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.