Input: add Wistron driver

A driver for laptop buttons using an x86 BIOS interface that is
apparently used on quite a few laptops and seems to be originating
from Wistron.

This driver currently "knows" only about Fujitsu-Siemens Amilo Pro V2000
(i.e. it can detect the laptop using DMI and it contains the
keycode->key meaning mapping for this laptop) and Xeron SonicPro X 155G
(probably can't be reliably autodetected, requires a module parameter),
adding other laptops should be easy.

In addition to reporting button presses to the input layer the driver
also allows enabling/disabling the embedded wireless NIC (using the
"Wifi" button); this is done using the same BIOS interface, so it seems
only logical to keep the implementation together.  Any flexibility
possibly gained by allowing users to remap the function of the "Wifi"
button is IMHO not worth it when weighted against the necessity to run
an user-space daemon to convert button presses to wifi state changes.

Signed-off-by: Miloslav Trmac <mitr@volny.cz>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

1 files changed, 443 insertions, 0 deletions

diff --git a/drivers/input/misc/wistron_btns.c b/drivers/input/misc/wistron_btns.c
new file mode 100644
index 000000000000..76d32e365b5d
--- /dev/null
+++ b/drivers/input/misc/wistron_btns.c
@@ -0,0 +1,443 @@
+/*
+ * Wistron laptop button driver
+ * Copyright (C) 2005 Miloslav Trmac <mitr@volny.cz>
+ *
+ * You can redistribute and/or modify this program under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation.
+ *
+ * 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.
+ */
+#include <asm/io.h>
+#include <linux/dmi.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mc146818rtc.h>
+#include <linux/module.h>
+#include <linux/preempt.h>
+#include <linux/string.h>
+#include <linux/timer.h>
+#include <linux/types.h>
+
+/*
+ * Number of attempts to read data from queue per poll;
+ * the queue can hold up to 31 entries
+ */
+#define MAX_POLL_ITERATIONS 64
+
+#define POLL_FREQUENCY 10 /* Number of polls per second */
+
+#if POLL_FREQUENCY > HZ
+#error "POLL_FREQUENCY too high"
+#endif
+
+MODULE_AUTHOR("Miloslav Trmac <mitr@volny.cz>");
+MODULE_DESCRIPTION("Wistron laptop button driver");
+MODULE_LICENSE("GPL v2");
+MODULE_VERSION("0.1");
+
+static int force; /* = 0; */
+module_param(force, bool, 0);
+MODULE_PARM_DESC(force, "Load even if computer is not in database");
+
+static char *keymap_name; /* = NULL; */
+module_param_named(keymap, keymap_name, charp, 0);
+MODULE_PARM_DESC(keymap, "Keymap name, if it can't be autodetected");
+
+ /* BIOS interface implementation */
+
+static void __iomem *bios_entry_point; /* BIOS routine entry point */
+static void __iomem *bios_code_map_base;
+static void __iomem *bios_data_map_base;
+
+static u8 cmos_address;
+
+struct regs {
+        u32 eax, ebx, ecx;
+};
+
+static void call_bios(struct regs *regs)
+{
+        unsigned long flags;
+
+        preempt_disable();
+        local_irq_save(flags);
+        asm volatile ("pushl %%ebp;"
+                      "movl %7, %%ebp;"
+                      "call *%6;"
+                      "popl %%ebp"
+                      : "=a" (regs->eax), "=b" (regs->ebx), "=c" (regs->ecx)
+                      : "0" (regs->eax), "1" (regs->ebx), "2" (regs->ecx),
+                        "m" (bios_entry_point), "m" (bios_data_map_base)
+                      : "edx", "edi", "esi", "memory");
+        local_irq_restore(flags);
+        preempt_enable();
+}
+
+static size_t __init locate_wistron_bios(void __iomem *base)
+{
+        static const unsigned char __initdata signature[] =
+                { 0x42, 0x21, 0x55, 0x30 };
+        size_t offset;
+
+        for (offset = 0; offset < 0x10000; offset += 0x10) {
+                if (check_signature(base + offset, signature,
+                                    sizeof(signature)) != 0)
+                        return offset;
+        }
+        return -1;
+}
+
+static int __init map_bios(void)
+{
+        void __iomem *base;
+        size_t offset;
+        u32 entry_point;
+
+        base = ioremap(0xF0000, 0x10000); /* Can't fail */
+        offset = locate_wistron_bios(base);
+        if (offset < 0) {
+                printk(KERN_ERR "wistron_btns: BIOS entry point not found\n");
+                iounmap(base);
+                return -ENODEV;
+        }
+
+        entry_point = readl(base + offset + 5);
+        printk(KERN_DEBUG
+                "wistron_btns: BIOS signature found at %p, entry point %08X\n",
+                base + offset, entry_point);
+
+        if (entry_point >= 0xF0000) {
+                bios_code_map_base = base;
+                bios_entry_point = bios_code_map_base + (entry_point & 0xFFFF);
+        } else {
+                iounmap(base);
+                bios_code_map_base = ioremap(entry_point & ~0x3FFF, 0x4000);
+                if (bios_code_map_base == NULL) {
+                        printk(KERN_ERR
+                                "wistron_btns: Can't map BIOS code at %08X\n",
+                                entry_point & ~0x3FFF);
+                        goto err;
+                }
+                bios_entry_point = bios_code_map_base + (entry_point & 0x3FFF);
+        }
+        /* The Windows driver maps 0x10000 bytes, we keep only one page... */
+        bios_data_map_base = ioremap(0x400, 0xc00);
+        if (bios_data_map_base == NULL) {
+                printk(KERN_ERR "wistron_btns: Can't map BIOS data\n");
+                goto err_code;
+        }
+        return 0;
+
+err_code:
+        iounmap(bios_code_map_base);
+err:
+        return -ENOMEM;
+}
+
+static void __exit unmap_bios(void)
+{
+        iounmap(bios_code_map_base);
+        iounmap(bios_data_map_base);
+}
+
+ /* BIOS calls */
+
+static u16 bios_pop_queue(void)
+{
+        struct regs regs;
+
+        memset(&regs, 0, sizeof (regs));
+        regs.eax = 0x9610;
+        regs.ebx = 0x061C;
+        regs.ecx = 0x0000;
+        call_bios(&regs);
+
+        return regs.eax;
+}
+
+static void __init bios_attach(void)
+{
+        struct regs regs;
+
+        memset(&regs, 0, sizeof (regs));
+        regs.eax = 0x9610;
+        regs.ebx = 0x012E;
+        call_bios(&regs);
+}
+
+static void __exit bios_detach(void)
+{
+        struct regs regs;
+
+        memset(&regs, 0, sizeof (regs));
+        regs.eax = 0x9610;
+        regs.ebx = 0x002E;
+        call_bios(&regs);
+}
+
+static u8 __init bios_get_cmos_address(void)
+{
+        struct regs regs;
+
+        memset(&regs, 0, sizeof (regs));
+        regs.eax = 0x9610;
+        regs.ebx = 0x051C;
+        call_bios(&regs);
+
+        return regs.ecx;
+}
+
+static u16 __init bios_wifi_get_default_setting(void)
+{
+        struct regs regs;
+
+        memset(&regs, 0, sizeof (regs));
+        regs.eax = 0x9610;
+        regs.ebx = 0x0235;
+        call_bios(&regs);
+
+        return regs.eax;
+}
+
+static void bios_wifi_set_state(int enable)
+{
+        struct regs regs;
+
+        memset(&regs, 0, sizeof (regs));
+        regs.eax = 0x9610;
+        regs.ebx = enable ? 0x0135 : 0x0035;
+        call_bios(&regs);
+}
+
+ /* Hardware database */
+
+struct key_entry {
+        char type;              /* See KE_* below */
+        u8 code;
+        unsigned keycode;       /* For KE_KEY */
+};
+
+enum { KE_END, KE_KEY, KE_WIFI };
+
+static const struct key_entry *keymap; /* = NULL; Current key map */
+static int have_wifi;
+
+static int __init dmi_matched(struct dmi_system_id *dmi)
+{
+        const struct key_entry *key;
+
+        keymap = dmi->driver_data;
+        for (key = keymap; key->type != KE_END; key++) {
+                if (key->type == KE_WIFI) {
+                        have_wifi = 1;
+                        break;
+                }
+        }
+        return 1;
+}
+
+static struct key_entry keymap_empty[] = {
+        { KE_END, 0 }
+};
+
+static struct key_entry keymap_fs_amilo_pro_v2000[] = {
+        { KE_KEY,  0x01, KEY_HELP },
+        { KE_KEY,  0x11, KEY_PROG1 },
+        { KE_KEY,  0x12, KEY_PROG2 },
+        { KE_WIFI, 0x30, 0 },
+        { KE_KEY,  0x31, KEY_MAIL },
+        { KE_KEY,  0x36, KEY_WWW },
+        { KE_END,  0 }
+};
+
+static struct key_entry keymap_wistron_ms2141[] = {
+        { KE_KEY,  0x11, KEY_PROG1 },
+        { KE_KEY,  0x12, KEY_PROG2 },
+        { KE_WIFI, 0x30, 0 },
+        { KE_KEY,  0x22, KEY_REWIND },
+        { KE_KEY,  0x23, KEY_FORWARD },
+        { KE_KEY,  0x24, KEY_PLAYPAUSE },
+        { KE_KEY,  0x25, KEY_STOPCD },
+        { KE_KEY,  0x31, KEY_MAIL },
+        { KE_KEY,  0x36, KEY_WWW },
+        { KE_END,  0 }
+};
+
+/*
+ * If your machine is not here (which is currently rather likely), please send
+ * a list of buttons and their key codes (reported when loading this module
+ * with force=1) and the output of dmidecode to $MODULE_AUTHOR.
+ */
+static struct dmi_system_id dmi_ids[] = {
+        {
+                .callback = dmi_matched,
+                .ident = "Fujitsu-Siemens Amilo Pro V2000",
+                .matches = {
+                        DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
+                        DMI_MATCH(DMI_PRODUCT_NAME, "AMILO Pro V2000"),
+                },
+                .driver_data = keymap_fs_amilo_pro_v2000
+        },
+        { 0, }
+};
+
+static int __init select_keymap(void)
+{
+        if (keymap_name != NULL) {
+                if (strcmp (keymap_name, "1557/MS2141") == 0)
+                        keymap = keymap_wistron_ms2141;
+                else {
+                        printk(KERN_ERR "wistron_btns: Keymap unknown\n");
+                        return -EINVAL;
+                }
+        }
+        dmi_check_system(dmi_ids);
+        if (keymap == NULL) {
+                if (!force) {
+                        printk(KERN_ERR "wistron_btns: System unknown\n");
+                        return -ENODEV;
+                }
+                keymap = keymap_empty;
+        }
+        return 0;
+}
+
+ /* Input layer interface */
+
+static struct input_dev input_dev = {
+        .name = "Wistron laptop buttons",
+};
+
+static void __init setup_input_dev(void)
+{
+        const struct key_entry *key;
+
+        for (key = keymap; key->type != KE_END; key++) {
+                if (key->type == KE_KEY) {
+                        input_dev.evbit[LONG(EV_KEY)] = BIT(EV_KEY);
+                        input_dev.keybit[LONG(key->keycode)]
+                                |= BIT(key->keycode);
+                }
+        }
+
+        input_register_device(&input_dev);
+}
+
+static void report_key(unsigned keycode)
+{
+        input_report_key(&input_dev, keycode, 1);
+        input_sync(&input_dev);
+        input_report_key(&input_dev, keycode, 0);
+        input_sync(&input_dev);
+}
+
+ /* Driver core */
+
+static int wifi_enabled;
+
+static void poll_bios(unsigned long);
+
+static struct timer_list poll_timer = TIMER_INITIALIZER(poll_bios, 0, 0);
+
+static void handle_key(u8 code)
+{
+        const struct key_entry *key;
+
+        for (key = keymap; key->type != KE_END; key++) {
+                if (code == key->code) {
+                        switch (key->type) {
+                        case KE_KEY:
+                                report_key(key->keycode);
+                                break;
+
+                        case KE_WIFI:
+                                if (have_wifi) {
+                                        wifi_enabled = !wifi_enabled;
+                                        bios_wifi_set_state(wifi_enabled);
+                                }
+                                break;
+
+                        case KE_END:
+                        default:
+                                BUG();
+                        }
+                        return;
+                }
+        }
+        printk(KERN_NOTICE "wistron_btns: Unknown key code %02X\n", code);
+}
+
+static void poll_bios(unsigned long discard)
+{
+        u8 qlen;
+        u16 val;
+
+        for (;;) {
+                qlen = CMOS_READ(cmos_address);
+                if (qlen == 0)
+                        break;
+                val = bios_pop_queue();
+                if (val != 0 && !discard)
+                        handle_key((u8)val);
+        }
+
+        mod_timer(&poll_timer, jiffies + HZ / POLL_FREQUENCY);
+}
+
+static int __init wb_module_init(void)
+{
+        int err;
+
+        err = select_keymap();
+        if (err)
+                return err;
+        err = map_bios();
+        if (err)
+                return err;
+        bios_attach();
+        cmos_address = bios_get_cmos_address();
+        if (have_wifi) {
+                switch (bios_wifi_get_default_setting()) {
+                case 0x01:
+                        wifi_enabled = 0;
+                        break;
+
+                case 0x03:
+                        wifi_enabled = 1;
+                        break;
+
+                default:
+                        have_wifi = 0;
+                        break;
+                }
+                if (have_wifi)
+                        bios_wifi_set_state(wifi_enabled);
+        }
+
+        setup_input_dev();
+
+        poll_bios(1); /* Flush stale event queue and arm timer */
+
+        return 0;
+}
+
+static void __exit wb_module_exit(void)
+{
+        del_timer_sync(&poll_timer);
+        input_unregister_device(&input_dev);
+        bios_detach();
+        unmap_bios();
+}
+
+module_init(wb_module_init);
+module_exit(wb_module_exit);