[PATCH] I8K: use standard DMI interface
Dmitry Torokhov [Sat, 25 Jun 2005 21:54:25 +0000 (14:54 -0700)]
I8K: Change to use stock dmi infrastructure instead of homegrown
     parsing code. The driver now requires box's DMI data to match
     list of supported models so driver can be safely compiled-in
     by default without fear of it poking into random SMM BIOS
     code. DMI checks can be ignored with i8k.ignore_dmi option.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

Documentation/kernel-parameters.txt
arch/i386/kernel/dmi_scan.c
drivers/char/i8k.c
include/linux/dmi.h

index 4924d38..86db43f 100644 (file)
@@ -548,6 +548,9 @@ running once the system is up.
 
        i810=           [HW,DRM]
 
+       i8k.ignore_dmi  [HW] Continue probing hardware even if DMI data
+                       indicates that the driver is running on unsupported
+                       hardware.
        i8k.force       [HW] Activate i8k driver even if SMM BIOS signature
                        does not match list of supported models.
        i8k.power_status
index 6ed7e28..3facd20 100644 (file)
@@ -414,6 +414,7 @@ static void __init dmi_decode(struct dmi_header *dm)
                        dmi_save_ident(dm, DMI_PRODUCT_VERSION, 6);
                        dmi_printk(("Serial Number: %s\n",
                                dmi_string(dm, data[7])));
+                       dmi_save_ident(dm, DMI_PRODUCT_SERIAL, 7);
                        break;
                case 2:
                        dmi_printk(("Board Vendor: %s\n",
@@ -470,7 +471,6 @@ fail:               d++;
 
        return count;
 }
-
 EXPORT_SYMBOL(dmi_check_system);
 
 /**
@@ -480,8 +480,8 @@ EXPORT_SYMBOL(dmi_check_system);
  *     Returns one DMI data value, can be used to perform
  *     complex DMI data checks.
  */
-char * dmi_get_system_info(int field)
+char *dmi_get_system_info(int field)
 {
        return dmi_ident[field];
 }
-
+EXPORT_SYMBOL(dmi_get_system_info);
index bf5e43b..81d2f67 100644 (file)
@@ -20,7 +20,7 @@
 #include <linux/types.h>
 #include <linux/init.h>
 #include <linux/proc_fs.h>
-#include <linux/apm_bios.h>
+#include <linux/dmi.h>
 #include <asm/uaccess.h>
 #include <asm/io.h>
 
 
 #define I8K_TEMPERATURE_BUG    1
 
-#define DELL_SIGNATURE         "Dell Computer"
-
-static char *supported_models[] = {
-       "Inspiron",
-       "Latitude",
-       NULL
-};
-
-static char system_vendor[48] = "?";
-static char product_name[48] = "?";
-static char bios_version[4] = "?";
-static char serial_number[16] = "?";
+static char bios_version[4];
 
 MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
 MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops");
@@ -73,6 +62,10 @@ static int force;
 module_param(force, bool, 0);
 MODULE_PARM_DESC(force, "Force loading without checking for supported models");
 
+static int ignore_dmi;
+module_param(ignore_dmi, bool, 0);
+MODULE_PARM_DESC(ignore_dmi, "Continue probing hardware even if DMI data does not match");
+
 static int restricted;
 module_param(restricted, bool, 0);
 MODULE_PARM_DESC(restricted, "Allow fan control if SYS_ADMIN capability set");
@@ -99,11 +92,10 @@ typedef struct {
        unsigned int edi __attribute__ ((packed));
 } SMMRegisters;
 
-typedef struct {
-       u8 type;
-       u8 length;
-       u16 handle;
-} DMIHeader;
+static inline char *i8k_get_dmi_data(int field)
+{
+       return dmi_get_system_info(field) ? : "N/A";
+}
 
 /*
  * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard.
@@ -163,15 +155,6 @@ static int i8k_get_bios_version(void)
 }
 
 /*
- * Read the machine id.
- */
-static int i8k_get_serial_number(unsigned char *buff)
-{
-       strlcpy(buff, serial_number, sizeof(serial_number));
-       return 0;
-}
-
-/*
  * Read the Fn key status.
  */
 static int i8k_get_fn_status(void)
@@ -328,7 +311,7 @@ static int i8k_get_dell_signature(void)
 static int i8k_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
                     unsigned long arg)
 {
-       int val;
+       int val = 0;
        int speed;
        unsigned char buff[16];
        int __user *argp = (int __user *)arg;
@@ -343,7 +326,7 @@ static int i8k_ioctl(struct inode *ip, struct file *fp, unsigned int cmd,
 
        case I8K_MACHINE_ID:
                memset(buff, 0, 16);
-               val = i8k_get_serial_number(buff);
+               strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff));
                break;
 
        case I8K_FN_STATUS:
@@ -451,10 +434,10 @@ static int i8k_get_info(char *buffer, char **start, off_t fpos, int length)
        n = sprintf(buffer, "%s %s %s %d %d %d %d %d %d %d\n",
                    I8K_PROC_FMT,
                    bios_version,
-                   serial_number,
+                   dmi_get_system_info(DMI_PRODUCT_SERIAL) ? : "N/A",
                    cpu_temp,
-                   left_fan,
-                   right_fan, left_speed, right_speed, ac_power, fn_key);
+                   left_fan, right_fan, left_speed, right_speed,
+                   ac_power, fn_key);
 
        return n;
 }
@@ -486,201 +469,23 @@ static ssize_t i8k_read(struct file *f, char __user * buffer, size_t len,
        return len;
 }
 
-static char *__init string_trim(char *s, int size)
-{
-       int len;
-       char *p;
-
-       if ((len = strlen(s)) > size) {
-               len = size;
-       }
-
-       for (p = s + len - 1; len && (*p == ' '); len--, p--) {
-               *p = '\0';
-       }
-
-       return s;
-}
-
-/* DMI code, stolen from arch/i386/kernel/dmi_scan.c */
-
-/*
- * |<-- dmi->length -->|
- * |                   |
- * |dmi header    s=N  | string1,\0, ..., stringN,\0, ..., \0
- *                |                       |
- *                +-----------------------+
- */
-static char *__init dmi_string(DMIHeader * dmi, u8 s)
-{
-       u8 *p;
-
-       if (!s) {
-               return "";
-       }
-       s--;
-
-       p = (u8 *) dmi + dmi->length;
-       while (s > 0) {
-               p += strlen(p);
-               p++;
-               s--;
-       }
-
-       return p;
-}
-
-static void __init dmi_decode(DMIHeader * dmi)
-{
-       u8 *data = (u8 *) dmi;
-       char *p;
-
-#ifdef I8K_DEBUG
-       int i;
-       printk("%08x ", (int)data);
-       for (i = 0; i < data[1] && i < 64; i++) {
-               printk("%02x ", data[i]);
-       }
-       printk("\n");
-#endif
-
-       switch (dmi->type) {
-       case 0:         /* BIOS Information */
-               p = dmi_string(dmi, data[5]);
-               if (*p) {
-                       strlcpy(bios_version, p, sizeof(bios_version));
-                       string_trim(bios_version, sizeof(bios_version));
-               }
-               break;
-       case 1:         /* System Information */
-               p = dmi_string(dmi, data[4]);
-               if (*p) {
-                       strlcpy(system_vendor, p, sizeof(system_vendor));
-                       string_trim(system_vendor, sizeof(system_vendor));
-               }
-               p = dmi_string(dmi, data[5]);
-               if (*p) {
-                       strlcpy(product_name, p, sizeof(product_name));
-                       string_trim(product_name, sizeof(product_name));
-               }
-               p = dmi_string(dmi, data[7]);
-               if (*p) {
-                       strlcpy(serial_number, p, sizeof(serial_number));
-                       string_trim(serial_number, sizeof(serial_number));
-               }
-               break;
-       }
-}
-
-static int __init dmi_table(u32 base, int len, int num,
-                           void (*fn) (DMIHeader *))
-{
-       u8 *buf;
-       u8 *data;
-       DMIHeader *dmi;
-       int i = 1;
-
-       buf = ioremap(base, len);
-       if (buf == NULL) {
-               return -1;
-       }
-       data = buf;
-
-       /*
-        * Stop when we see al the items the table claimed to have
-        * or we run off the end of the table (also happens)
-        */
-       while ((i < num) && ((data - buf) < len)) {
-               dmi = (DMIHeader *) data;
-               /*
-                * Avoid misparsing crud if the length of the last
-                * record is crap
-                */
-               if ((data - buf + dmi->length) >= len) {
-                       break;
-               }
-               fn(dmi);
-               data += dmi->length;
-               /*
-                * Don't go off the end of the data if there is
-                * stuff looking like string fill past the end
-                */
-               while (((data - buf) < len) && (*data || data[1])) {
-                       data++;
-               }
-               data += 2;
-               i++;
-       }
-       iounmap(buf);
-
-       return 0;
-}
-
-static int __init dmi_iterate(void (*decode) (DMIHeader *))
-{
-       unsigned char buf[20];
-       void __iomem *p = ioremap(0xe0000, 0x20000), *q;
-
-       if (!p)
-               return -1;
-
-       for (q = p; q < p + 0x20000; q += 16) {
-               memcpy_fromio(buf, q, 20);
-               if (memcmp(buf, "_DMI_", 5) == 0) {
-                       u16 num  = buf[13] << 8 | buf[12];
-                       u16 len  = buf[7] << 8 | buf[6];
-                       u32 base = buf[11] << 24 | buf[10] << 16 | buf[9] << 8 | buf[8];
-#ifdef I8K_DEBUG
-                       printk(KERN_INFO "DMI %d.%d present.\n",
-                              buf[14] >> 4, buf[14] & 0x0F);
-                       printk(KERN_INFO "%d structures occupying %d bytes.\n",
-                              buf[13] << 8 | buf[12], buf[7] << 8 | buf[6]);
-                       printk(KERN_INFO "DMI table at 0x%08X.\n",
-                              buf[11] << 24 | buf[10] << 16 | buf[9] << 8 |
-                              buf[8]);
-#endif
-                       if (dmi_table(base, len, num, decode) == 0) {
-                               iounmap(p);
-                               return 0;
-                       }
-               }
-       }
-       iounmap(p);
-       return -1;
-}
-
-/* end of DMI code */
-
-/*
- * Get DMI information.
- */
-static int __init i8k_dmi_probe(void)
-{
-       char **p;
-
-       if (dmi_iterate(dmi_decode) != 0) {
-               printk(KERN_INFO "i8k: unable to get DMI information\n");
-               return -ENODEV;
-       }
-
-       if (strncmp(system_vendor, DELL_SIGNATURE, strlen(DELL_SIGNATURE)) != 0) {
-               printk(KERN_INFO "i8k: not running on a Dell system\n");
-               return -ENODEV;
-       }
-
-       for (p = supported_models;; p++) {
-               if (!*p) {
-                       printk(KERN_INFO "i8k: unsupported model: %s\n",
-                              product_name);
-                       return -ENODEV;
-               }
-               if (strncmp(product_name, *p, strlen(*p)) == 0) {
-                       break;
-               }
-       }
-
-       return 0;
-}
+static struct dmi_system_id __initdata i8k_dmi_table[] = {
+       {
+               .ident = "Dell Inspiron",
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"),
+               },
+       },
+       {
+               .ident = "Dell Latitude",
+               .matches = {
+                       DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer"),
+                       DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"),
+               },
+       },
+       { }
+};
 
 /*
  * Probe for the presence of a supported laptop.
@@ -689,23 +494,30 @@ static int __init i8k_probe(void)
 {
        char buff[4];
        int version;
-       int smm_found = 0;
 
        /*
         * Get DMI information
         */
-       if (i8k_dmi_probe() != 0) {
+       if (!dmi_check_system(i8k_dmi_table)) {
+               if (!ignore_dmi && !force)
+                       return -ENODEV;
+
+               printk(KERN_INFO "i8k: not running on a supported Dell system.\n");
                printk(KERN_INFO "i8k: vendor=%s, model=%s, version=%s\n",
-                      system_vendor, product_name, bios_version);
+                       i8k_get_dmi_data(DMI_SYS_VENDOR),
+                       i8k_get_dmi_data(DMI_PRODUCT_NAME),
+                       i8k_get_dmi_data(DMI_BIOS_VERSION));
        }
 
+       strlcpy(bios_version, i8k_get_dmi_data(DMI_BIOS_VERSION), sizeof(bios_version));
+
        /*
         * Get SMM Dell signature
         */
        if (i8k_get_dell_signature() != 0) {
-               printk(KERN_INFO "i8k: unable to get SMM Dell signature\n");
-       } else {
-               smm_found = 1;
+               printk(KERN_ERR "i8k: unable to get SMM Dell signature\n");
+               if (!force)
+                       return -ENODEV;
        }
 
        /*
@@ -713,9 +525,8 @@ static int __init i8k_probe(void)
         */
        version = i8k_get_bios_version();
        if (version <= 0) {
-               printk(KERN_INFO "i8k: unable to get SMM BIOS version\n");
+               printk(KERN_WARNING "i8k: unable to get SMM BIOS version\n");
        } else {
-               smm_found = 1;
                buff[0] = (version >> 16) & 0xff;
                buff[1] = (version >> 8) & 0xff;
                buff[2] = (version) & 0xff;
@@ -723,21 +534,15 @@ static int __init i8k_probe(void)
                /*
                 * If DMI BIOS version is unknown use SMM BIOS version.
                 */
-               if (bios_version[0] == '?') {
-                       strcpy(bios_version, buff);
-               }
+               if (!dmi_get_system_info(DMI_BIOS_VERSION))
+                       strlcpy(bios_version, buff, sizeof(bios_version));
+
                /*
                 * Check if the two versions match.
                 */
-               if (strncmp(buff, bios_version, sizeof(bios_version)) != 0) {
-                       printk(KERN_INFO
-                              "i8k: BIOS version mismatch: %s != %s\n", buff,
-                              bios_version);
-               }
-       }
-
-       if (!smm_found && !force) {
-               return -ENODEV;
+               if (strncmp(buff, bios_version, sizeof(bios_version)) != 0)
+                       printk(KERN_WARNING "i8k: BIOS version mismatch: %s != %s\n",
+                               buff, bios_version);
        }
 
        return 0;
@@ -751,9 +556,8 @@ int __init i8k_init(void)
        struct proc_dir_entry *proc_i8k;
 
        /* Are we running on an supported laptop? */
-       if (i8k_probe() != 0) {
+       if (i8k_probe())
                return -ENODEV;
-       }
 
        /* Register the proc entry */
        proc_i8k = create_proc_info_entry("i8k", 0, NULL, i8k_get_info);
index d2bcf55..5e93e6d 100644 (file)
@@ -9,6 +9,7 @@ enum dmi_field {
        DMI_SYS_VENDOR,
        DMI_PRODUCT_NAME,
        DMI_PRODUCT_VERSION,
+       DMI_PRODUCT_SERIAL,
        DMI_BOARD_VENDOR,
        DMI_BOARD_NAME,
        DMI_BOARD_VERSION,