Toshiba laptops enable special functionality via an ACPI device. This

driver handles that, and will be maintained by John Belmonte.

MAINTAINERS

@@ -1590,6 +1590,12 @@ L:	linux-tr@linuxtr.net
 W:	http://www.linuxtr.net
 S:	Maintained
 
+TOSHIBA ACPI EXTRAS DRIVER
+P:	John Belmonte
+M:	toshiba_acpi@memebeam.org
+W:	http://memebeam.org/toys/ToshibaAcpiDriver
+S:	Maintained
+
 TOSHIBA SMM DRIVER
 P:	Jonathan Buzzard
 M:	jonathan@buzzard.org.uk

drivers/acpi/Config.help

@@ -91,3 +91,25 @@ CONFIG_ACPI_DEBUG
   of verbosity. Saying Y enables these statements. This will increase
   your kernel size by around 50K.
 
+CONFIG_ACPI_TOSHIBA
+  This driver adds support for access to certain system settings
+  on "legacy free" Toshiba laptops.  These laptops can be recognized by
+  their lack of a BIOS setup menu and APM support.
+
+  On these machines, all system configuration is handled through the
+  ACPI.  This driver is required for access to controls not covered
+  by the general ACPI drivers, such as LCD brightness, video output,
+  etc.
+
+  This driver differs from the non-ACPI Toshiba laptop driver (located
+  under "Processor type and features") in several aspects.
+  Configuration is accessed by reading and writing text files in the
+  /proc tree instead of by program interface to /dev.  Furthermore, no
+  power management functions are exposed, as those are handled by the
+  general ACPI drivers.
+
+  More information about this driver is available at
+  <http://memebeam.org/toys/ToshibaAcpiDriver>.
+
+  If you have a legacy free Toshiba laptop (such as the Libretto L1
+  series), say Y.

drivers/acpi/Config.in

@@ -31,6 +31,7 @@ if [ "$CONFIG_X86" = "y" ]; then
       tristate     '  Fan'		CONFIG_ACPI_FAN
       tristate     '  Processor'	CONFIG_ACPI_PROCESSOR
       dep_tristate '  Thermal Zone' 	CONFIG_ACPI_THERMAL $CONFIG_ACPI_PROCESSOR
+      tristate     '  Toshiba Laptop Extras'	CONFIG_ACPI_TOSHIBA
       bool         '  Debug Statements'	CONFIG_ACPI_DEBUG
     fi
   fi

drivers/acpi/Makefile

@@ -43,5 +43,6 @@ obj-$(CONFIG_ACPI_POWER)	+= power.o
 obj-$(CONFIG_ACPI_PROCESSOR)	+= processor.o
 obj-$(CONFIG_ACPI_THERMAL)	+= thermal.o
 obj-$(CONFIG_ACPI_SYSTEM)	+= system.o
+obj-$(CONFIG_ACPI_TOSHIBA)	+= toshiba_acpi.o
 
 include $(TOPDIR)/Rules.make

drivers/acpi/toshiba_acpi.c

+/*
+ *  toshiba_acpi.c - Toshiba Laptop ACPI Extras
+ *
+ *
+ *  Copyright (C) 2002 John Belmonte
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *
+ *  The devolpment page for this driver is located at
+ *  http://memebeam.org/toys/ToshibaAcpiDriver.
+ *
+ *  Credits:
+ *	Jonathan A. Buzzard - Toshiba HCI info, and critical tips on reverse
+ *		engineering the Windows drivers
+ *	Yasushi Nagato - changes for linux kernel 2.4 -> 2.5
+ *
+ *
+ *  TODO
+ *	provide version info in proc
+ *	add Fn key status
+ *
+ */
+
+#define TOSHIBA_ACPI_VERSION "0.12"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/proc_fs.h>
+#include <linux/version.h>
+
+#define KERNEL24 (LINUX_VERSION_CODE < KERNEL_VERSION(2, 5, 0))
+
+#if KERNEL24
+#include <acpi.h>
+extern struct proc_dir_entry* bm_proc_root;
+#define acpi_root_dir bm_proc_root
+#else
+#include "acpi_drivers.h"
+#endif
+
+MODULE_AUTHOR("John Belmonte");
+MODULE_DESCRIPTION("Toshiba Laptop ACPI Extras Driver");
+MODULE_LICENSE("GPL");
+
+/* Toshiba ACPI method paths */
+#define METHOD_LCD_BRIGHTNESS	"\\_SB_.PCI0.VGA_.LCD_._BCM"
+#define METHOD_HCI		"\\_SB_.VALD.GHCI"
+#define METHOD_VIDEO_OUT	"\\_SB_.VALX.DSSX"
+
+/* Toshiba HCI interface definitions
+ *
+ * HCI is Toshiba's "Hardware Control Interface" which is supposed to
+ * be uniform across all their models.  Ideally we would just call
+ * dedicated ACPI methods instead of using this primitive interface.
+ * However the ACPI methods seem to be incomplete in some areas (for
+ * example they allow setting, but not reading, the LCD brightness value),
+ * so this is still useful.
+ */
+
+#define HCI_WORDS			6
+
+/* operations */
+#define HCI_SET				0xff00
+#define HCI_GET				0xfe00
+
+/* return codes */
+#define HCI_SUCCESS			0x0000
+#define HCI_FAILURE			0x1000
+#define HCI_NOT_SUPPORTED		0x8000
+
+/* registers */
+#define HCI_FAN				0x0004
+#define HCI_VIDEO_OUT			0x001c
+#define HCI_LCD_BRIGHTNESS		0x002a
+
+/* field definitions */
+#define HCI_LCD_BRIGHTNESS_BITS		3
+#define HCI_LCD_BRIGHTNESS_SHIFT	(16-HCI_LCD_BRIGHTNESS_BITS)
+#define HCI_LCD_BRIGHTNESS_LEVELS	(1 << HCI_LCD_BRIGHTNESS_BITS)
+#define HCI_VIDEO_OUT_LCD		0x1
+#define HCI_VIDEO_OUT_CRT		0x2
+
+/* utility
+ */
+
+static __inline__ void
+_set_bit(u32* word, u32 mask, int value)
+{
+	*word = (*word & ~mask) | (mask * value);
+}
+
+/* This is the common code at the end of every proc read handler.  I don't
+ * understand it yet.
+ */
+static int
+end_proc_read(const char* p, char* page, off_t off, int count,
+	char** start, int* eof)
+{
+	int len = (p - page);
+	if (len <= off+count) *eof = 1;
+	*start = page + off;
+	len -= off;
+	if (len>count) len = count;
+	if (len<0) len = 0;
+	return len;
+}
+
+/* acpi interface wrappers
+ */
+
+static int
+write_acpi_int(const char* methodName, int val)
+{
+	acpi_object_list params;
+	acpi_object in_objs[1];
+	acpi_status status;
+
+	params.count = sizeof(in_objs)/sizeof(in_objs[0]);
+	params.pointer = in_objs;
+	in_objs[0].type = ACPI_TYPE_INTEGER;
+	in_objs[0].integer.value = val;
+
+	status = acpi_evaluate_object(0, (char*)methodName, &params, 0);
+	return (status == AE_OK);
+}
+
+#if 0
+static int
+read_acpi_int(const char* methodName, int* pVal)
+{
+	acpi_buffer results;
+	acpi_object out_objs[1];
+	acpi_status status;
+
+	results.length = sizeof(out_objs);
+	results.pointer = out_objs;
+
+	status = acpi_evaluate_object(0, (char*)methodName, 0, &results);
+	*pVal = out_objs[0].integer.value;
+
+	return (status == AE_OK) && (out_objs[0].type == ACPI_TYPE_INTEGER);
+}
+#endif
+
+/* Perform a raw HCI call.  Here we don't care about input or output buffer
+ * format.
+ */
+static acpi_status
+hci_raw(const u32 in[HCI_WORDS], u32 out[HCI_WORDS])
+{
+	acpi_object_list params;
+	acpi_object in_objs[HCI_WORDS];
+	acpi_buffer results;
+	acpi_object out_objs[HCI_WORDS+1];
+	acpi_status status;
+	int i;
+
+	params.count = HCI_WORDS;
+	params.pointer = in_objs;
+	for (i = 0; i < HCI_WORDS; ++i) {
+		in_objs[i].type = ACPI_TYPE_INTEGER;
+		in_objs[i].integer.value = in[i];
+		/*printk("%04x ", in[i]);*/
+	}
+	/*printk("\n");*/
+
+	results.length = sizeof(out_objs);
+	results.pointer = out_objs;
+
+	status = acpi_evaluate_object(0, METHOD_HCI, &params,
+		&results);
+	if ((status == AE_OK) && (out_objs->package.count <= HCI_WORDS)) {
+		for (i = 0; i < out_objs->package.count; ++i) {
+			out[i] = out_objs->package.elements[i].integer.value;
+			/*printk("%04x ", out[i]);*/
+		}
+		/*printk("\n");*/
+	}
+
+	return status;
+}
+
+/* common hci tasks (get or set one value)
+ *
+ * In addition to the ACPI status, the HCI system returns a result which
+ * may be useful (such as "not supported").
+ */
+
+static acpi_status
+hci_write1(u32 reg, u32 in1, u32* result)
+{
+	u32 in[HCI_WORDS] = { HCI_SET, reg, in1, 0, 0, 0 };
+	u32 out[HCI_WORDS];
+	acpi_status status = hci_raw(in, out);
+	*result = (status == AE_OK) ? out[0] : HCI_FAILURE;
+	return status;
+}
+
+static acpi_status
+hci_read1(u32 reg, u32* out1, u32* result)
+{
+	u32 in[HCI_WORDS] = { HCI_GET, reg, 0, 0, 0, 0 };
+	u32 out[HCI_WORDS];
+	acpi_status status = hci_raw(in, out);
+	*out1 = out[2];
+	*result = (status == AE_OK) ? out[0] : HCI_FAILURE;
+	return status;
+}
+
+#define PROC_TOSHIBA		"toshiba"
+#define PROC_LCD		"lcd"
+#define PROC_VIDEO		"video"
+#define PROC_FAN		"fan"
+
+static struct proc_dir_entry*	toshiba_proc_dir = NULL;
+static int			force_fan;
+
+/* proc file handlers
+ *
+ * WARNING: The write handlers are using sscanf on non-zero-terminated
+ * buffers.  This may result in memory reads past the buffer bounds.
+ */
+
+static int
+proc_read_lcd(char* page, char** start, off_t off, int count, int* eof,
+	void* context)
+{
+	char* p = page;
+	u32 hci_result;
+	u32 value;
+
+	if (off != 0) goto end;
+
+	hci_read1(HCI_LCD_BRIGHTNESS, &value, &hci_result);
+	if (hci_result == HCI_SUCCESS) {
+		value = value >> HCI_LCD_BRIGHTNESS_SHIFT;
+		p += sprintf(p, "brightness:              %d\n", value);
+		p += sprintf(p, "brightness_levels:       %d\n",
+			HCI_LCD_BRIGHTNESS_LEVELS);
+	} else {
+		p += sprintf(p, "ERROR\n");
+		goto end;
+	}
+
+end:
+	return end_proc_read(p, page, off, count, start, eof);
+}
+
+static int
+proc_write_lcd(struct file* file, const char* buffer, unsigned long count,
+	void* data)
+{
+	int value;
+	/*int byte_count;*/
+	u32 hci_result;
+
+	/* ISSUE: %i doesn't work with hex values as advertised */
+	if (sscanf(buffer, " brightness : %i", &value) == 1 &&
+			value >= 0 && value < HCI_LCD_BRIGHTNESS_LEVELS) {
+		value = value << HCI_LCD_BRIGHTNESS_SHIFT;
+		hci_write1(HCI_LCD_BRIGHTNESS, value, &hci_result);
+		if (hci_result != HCI_SUCCESS)
+			return -EFAULT;
+	} else {
+		return -EINVAL;
+	}
+
+	return count;
+}
+
+static int
+proc_read_video(char* page, char** start, off_t off, int count, int* eof,
+	void* context)
+{
+	char* p = page;
+	u32 hci_result;
+	u32 value;
+
+	if (off != 0) goto end;
+
+	hci_read1(HCI_VIDEO_OUT, &value, &hci_result);
+	if (hci_result == HCI_SUCCESS) {
+		int is_lcd = (value & HCI_VIDEO_OUT_LCD) ? 1 : 0;
+		int is_crt = (value & HCI_VIDEO_OUT_CRT) ? 1 : 0;
+		p += sprintf(p, "lcd_out:                 %d\n", is_lcd);
+		p += sprintf(p, "crt_out:                 %d\n", is_crt);
+	} else {
+		p += sprintf(p, "ERROR\n");
+		goto end;
+	}
+
+end:
+	return end_proc_read(p, page, off, count, start, eof);
+}
+
+static int
+proc_write_video(struct file* file, const char* buffer, unsigned long count,
+	void* data)
+{
+	int value;
+	const char* buffer_end = buffer + count;
+	int lcd_out = -1;
+	int crt_out = -1;
+	u32 hci_result;
+	int video_out;
+
+	/* scan expression.  Multiple expressions may be delimited with ; */
+	do {
+		if (sscanf(buffer, " lcd_out : %i", &value) == 1)
+			lcd_out = value & 1;
+		else if (sscanf(buffer, " crt_out : %i", &value) == 1)
+			crt_out = value & 1;
+		/* advance to one character past the next ; */
+		do ++buffer;
+		while ((buffer < buffer_end) && (*(buffer-1) != ';'));
+	} while (buffer < buffer_end);
+
+	hci_read1(HCI_VIDEO_OUT, &video_out, &hci_result);
+	if (hci_result == HCI_SUCCESS) {
+		int new_video_out = video_out;
+		if (lcd_out != -1)
+			_set_bit(&new_video_out, HCI_VIDEO_OUT_LCD, lcd_out);
+		if (crt_out != -1)
+			_set_bit(&new_video_out, HCI_VIDEO_OUT_CRT, crt_out);
+		/* To avoid unnecessary video disruption, only write the new
+		 * video setting if something changed. */
+		if (new_video_out != video_out)
+			write_acpi_int(METHOD_VIDEO_OUT, new_video_out);
+	}
+
+	return count;
+}
+
+static int
+proc_read_fan(char* page, char** start, off_t off, int count, int* eof,
+	void* context)
+{
+	char* p = page;
+	u32 hci_result;
+	u32 value;
+
+	if (off != 0) goto end;
+
+	hci_read1(HCI_FAN, &value, &hci_result);
+	if (hci_result == HCI_SUCCESS) {
+		p += sprintf(p, "running:                 %d\n", (value > 0));
+		p += sprintf(p, "force_on:                %d\n", force_fan);
+	} else {
+		p += sprintf(p, "ERROR\n");
+		goto end;
+	}
+
+end:
+	return end_proc_read(p, page, off, count, start, eof);
+}
+
+static int
+proc_write_fan(struct file* file, const char* buffer, unsigned long count,
+	void* data)
+{
+	int value;
+	u32 hci_result;
+
+	if (sscanf(buffer, " force_on : %i", &value) == 1 &&
+			value >= 0 && value <= 1) {
+		hci_write1(HCI_FAN, value, &hci_result);
+		if (hci_result != HCI_SUCCESS)
+			return -EFAULT;
+		else
+			force_fan = value;
+	} else {
+		return -EINVAL;
+	}
+
+	return count;
+}
+
+/* proc and module init
+ */
+
+static acpi_status
+add_device(void)
+{
+	struct proc_dir_entry* proc;
+
+	proc = create_proc_read_entry(PROC_LCD, S_IFREG | S_IRUGO | S_IWUSR,
+		toshiba_proc_dir, proc_read_lcd, 0);
+	if (proc) proc->write_proc = proc_write_lcd;
+
+	proc = create_proc_read_entry(PROC_VIDEO, S_IFREG | S_IRUGO | S_IWUSR,
+		toshiba_proc_dir, proc_read_video, 0);
+	if (proc) proc->write_proc = proc_write_video;
+
+	proc = create_proc_read_entry(PROC_FAN, S_IFREG | S_IRUGO | S_IWUSR,
+		toshiba_proc_dir, proc_read_fan, 0);
+	if (proc) proc->write_proc = proc_write_fan;
+
+	return(AE_OK);
+}
+
+static acpi_status
+remove_device(void)
+{
+	remove_proc_entry(PROC_LCD, toshiba_proc_dir);
+	remove_proc_entry(PROC_VIDEO, toshiba_proc_dir);
+	remove_proc_entry(PROC_FAN, toshiba_proc_dir);
+	return(AE_OK);
+}
+
+static int __init
+toshiba_acpi_init(void)
+{
+	acpi_status status = AE_OK;
+	int value;
+	u32 hci_result;
+
+	/* simple device detection: try reading an HCI register */
+	hci_read1(HCI_LCD_BRIGHTNESS, &value, &hci_result);
+	if (hci_result != HCI_SUCCESS)
+		return -ENODEV;
+
+	printk("Toshiba Laptop ACPI Extras version %s\n", TOSHIBA_ACPI_VERSION);
+
+	force_fan = 0;
+
+	toshiba_proc_dir = proc_mkdir(PROC_TOSHIBA, acpi_root_dir);
+	if (!toshiba_proc_dir) {
+		status = AE_ERROR;
+	} else {
+		status = add_device();
+		if (ACPI_FAILURE(status))
+			remove_proc_entry(PROC_TOSHIBA, acpi_root_dir);
+	}
+
+	return (ACPI_SUCCESS(status)) ? 0 : -ENODEV;
+}
+
+static void __exit
+toshiba_acpi_exit(void)
+{
+	remove_device();
+
+	if (toshiba_proc_dir)
+		remove_proc_entry(PROC_TOSHIBA, acpi_root_dir);
+
+	return;
+}
+
+module_init(toshiba_acpi_init);
+module_exit(toshiba_acpi_exit);