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/*
 *      crc16.c
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2. See the file COPYING for more details.
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/crc16.h>

/** CRC table for the CRC-16. The poly is 0x8005 (x^16 + x^15 + x^2 + 1) */
u16 const crc16_table[256] = {
	0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
	0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
	0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
	0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
	0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
	0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
	0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
	0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
	0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
	0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
	0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
	0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
	0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
	0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
	0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
	0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
	0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
	0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
	0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
	0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
	0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
	0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
	0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
	0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
	0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
	0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
	0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
	0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
	0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
	0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
	0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
	0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
};
EXPORT_SYMBOL(crc16_table);

/**
 * Compute the CRC-16 for the data buffer
 *
 * @param crc     previous CRC value
 * @param buffer  data pointer
 * @param len     number of bytes in the buffer
 * @return        the updated CRC value
 */
u16 crc16(u16 crc, u8 const *buffer, size_t len)
{
	while (len--)
		crc = crc16_byte(crc, *buffer++);
	return crc;
}
EXPORT_SYMBOL(crc16);

MODULE_DESCRIPTION("CRC16 calculations");
MODULE_LICENSE("GPL");

> */ #include <linux/module.h> #include <linux/types.h> #include <linux/init.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/dmi.h> #include <linux/capability.h> #include <asm/uaccess.h> #include <asm/io.h> #include <linux/i8k.h> #define I8K_VERSION "1.14 21/02/2005" #define I8K_SMM_FN_STATUS 0x0025 #define I8K_SMM_POWER_STATUS 0x0069 #define I8K_SMM_SET_FAN 0x01a3 #define I8K_SMM_GET_FAN 0x00a3 #define I8K_SMM_GET_SPEED 0x02a3 #define I8K_SMM_GET_TEMP 0x10a3 #define I8K_SMM_GET_DELL_SIG1 0xfea3 #define I8K_SMM_GET_DELL_SIG2 0xffa3 #define I8K_SMM_BIOS_VERSION 0x00a6 #define I8K_FAN_MULT 30 #define I8K_MAX_TEMP 127 #define I8K_FN_NONE 0x00 #define I8K_FN_UP 0x01 #define I8K_FN_DOWN 0x02 #define I8K_FN_MUTE 0x04 #define I8K_FN_MASK 0x07 #define I8K_FN_SHIFT 8 #define I8K_POWER_AC 0x05 #define I8K_POWER_BATTERY 0x01 #define I8K_TEMPERATURE_BUG 1 static char bios_version[4]; MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)"); MODULE_DESCRIPTION("Driver for accessing SMM BIOS on Dell laptops"); MODULE_LICENSE("GPL"); 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"); static int power_status; module_param(power_status, bool, 0600); MODULE_PARM_DESC(power_status, "Report power status in /proc/i8k"); static int fan_mult = I8K_FAN_MULT; module_param(fan_mult, int, 0); MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with"); static int i8k_open_fs(struct inode *inode, struct file *file); static int i8k_ioctl(struct inode *, struct file *, unsigned int, unsigned long); static const struct file_operations i8k_fops = { .owner = THIS_MODULE, .open = i8k_open_fs, .read = seq_read, .llseek = seq_lseek, .release = single_release, .ioctl = i8k_ioctl, }; struct smm_regs { unsigned int eax; unsigned int ebx __attribute__ ((packed)); unsigned int ecx __attribute__ ((packed)); unsigned int edx __attribute__ ((packed)); unsigned int esi __attribute__ ((packed)); unsigned int edi __attribute__ ((packed)); }; static inline const char *i8k_get_dmi_data(int field) { const char *dmi_data = dmi_get_system_info(field); return dmi_data && *dmi_data ? dmi_data : "?"; } /* * Call the System Management Mode BIOS. Code provided by Jonathan Buzzard. */ static int i8k_smm(struct smm_regs *regs) { int rc; int eax = regs->eax; #if defined(CONFIG_X86_64) asm("pushq %%rax\n\t" "movl 0(%%rax),%%edx\n\t" "pushq %%rdx\n\t" "movl 4(%%rax),%%ebx\n\t" "movl 8(%%rax),%%ecx\n\t" "movl 12(%%rax),%%edx\n\t" "movl 16(%%rax),%%esi\n\t" "movl 20(%%rax),%%edi\n\t" "popq %%rax\n\t" "out %%al,$0xb2\n\t" "out %%al,$0x84\n\t" "xchgq %%rax,(%%rsp)\n\t" "movl %%ebx,4(%%rax)\n\t" "movl %%ecx,8(%%rax)\n\t" "movl %%edx,12(%%rax)\n\t" "movl %%esi,16(%%rax)\n\t" "movl %%edi,20(%%rax)\n\t" "popq %%rdx\n\t" "movl %%edx,0(%%rax)\n\t" "lahf\n\t" "shrl $8,%%eax\n\t" "andl $1,%%eax\n" :"=a"(rc) : "a"(regs) : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory"); #else asm("pushl %%eax\n\t" "movl 0(%%eax),%%edx\n\t" "push %%edx\n\t" "movl 4(%%eax),%%ebx\n\t" "movl 8(%%eax),%%ecx\n\t" "movl 12(%%eax),%%edx\n\t" "movl 16(%%eax),%%esi\n\t" "movl 20(%%eax),%%edi\n\t" "popl %%eax\n\t" "out %%al,$0xb2\n\t" "out %%al,$0x84\n\t" "xchgl %%eax,(%%esp)\n\t" "movl %%ebx,4(%%eax)\n\t" "movl %%ecx,8(%%eax)\n\t" "movl %%edx,12(%%eax)\n\t" "movl %%esi,16(%%eax)\n\t" "movl %%edi,20(%%eax)\n\t" "popl %%edx\n\t" "movl %%edx,0(%%eax)\n\t" "lahf\n\t" "shrl $8,%%eax\n\t" "andl $1,%%eax\n":"=a"(rc) : "a"(regs) : "%ebx", "%ecx", "%edx", "%esi", "%edi", "memory"); #endif if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax) return -EINVAL; return 0; } /* * Read the bios version. Return the version as an integer corresponding * to the ascii value, for example "A17" is returned as 0x00413137. */ static int i8k_get_bios_version(void) { struct smm_regs regs = { .eax = I8K_SMM_BIOS_VERSION, }; return i8k_smm(&regs) ? : regs.eax; } /* * Read the Fn key status. */ static int i8k_get_fn_status(void) { struct smm_regs regs = { .eax = I8K_SMM_FN_STATUS, }; int rc; if ((rc = i8k_smm(&regs)) < 0) return rc; switch ((regs.eax >> I8K_FN_SHIFT) & I8K_FN_MASK) { case I8K_FN_UP: return I8K_VOL_UP; case I8K_FN_DOWN: return I8K_VOL_DOWN; case I8K_FN_MUTE: return I8K_VOL_MUTE; default: return 0; } } /* * Read the power status. */ static int i8k_get_power_status(void) { struct smm_regs regs = { .eax = I8K_SMM_POWER_STATUS, }; int rc; if ((rc = i8k_smm(&regs)) < 0) return rc; return (regs.eax & 0xff) == I8K_POWER_AC ? I8K_AC : I8K_BATTERY; } /* * Read the fan status. */ static int i8k_get_fan_status(int fan) { struct smm_regs regs = { .eax = I8K_SMM_GET_FAN, }; regs.ebx = fan & 0xff; return i8k_smm(&regs) ? : regs.eax & 0xff; } /* * Read the fan speed in RPM. */ static int i8k_get_fan_speed(int fan) { struct smm_regs regs = { .eax = I8K_SMM_GET_SPEED, }; regs.ebx = fan & 0xff; return i8k_smm(&regs) ? : (regs.eax & 0xffff) * fan_mult; } /* * Set the fan speed (off, low, high). Returns the new fan status. */ static int i8k_set_fan(int fan, int speed) { struct smm_regs regs = { .eax = I8K_SMM_SET_FAN, }; speed = (speed < 0) ? 0 : ((speed > I8K_FAN_MAX) ? I8K_FAN_MAX : speed); regs.ebx = (fan & 0xff) | (speed << 8); return i8k_smm(&regs) ? : i8k_get_fan_status(fan); } /* * Read the cpu temperature. */ static int i8k_get_temp(int sensor) { struct smm_regs regs = { .eax = I8K_SMM_GET_TEMP, }; int rc; int temp; #ifdef I8K_TEMPERATURE_BUG static int prev; #endif regs.ebx = sensor & 0xff; if ((rc = i8k_smm(&regs)) < 0) return rc; temp = regs.eax & 0xff; #ifdef I8K_TEMPERATURE_BUG /* * Sometimes the temperature sensor returns 0x99, which is out of range. * In this case we return (once) the previous cached value. For example: # 1003655137 00000058 00005a4b # 1003655138 00000099 00003a80 <--- 0x99 = 153 degrees # 1003655139 00000054 00005c52 */ if (temp > I8K_MAX_TEMP) { temp = prev; prev = I8K_MAX_TEMP; } else { prev = temp; } #endif return temp; } static int i8k_get_dell_signature(int req_fn) { struct smm_regs regs = { .eax = req_fn, }; int rc; if ((rc = i8k_smm(&regs)) < 0) return rc; return regs.eax == 1145651527 && regs.edx == 1145392204 ? 0 : -1; } static int i8k_ioctl(struct inode *ip, struct file *fp, unsigned int cmd, unsigned long arg) { int val = 0; int speed; unsigned char buff[16]; int __user *argp = (int __user *)arg; if (!argp) return -EINVAL; switch (cmd) { case I8K_BIOS_VERSION: val = i8k_get_bios_version(); break; case I8K_MACHINE_ID: memset(buff, 0, 16); strlcpy(buff, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), sizeof(buff)); break; case I8K_FN_STATUS: val = i8k_get_fn_status(); break; case I8K_POWER_STATUS: val = i8k_get_power_status(); break; case I8K_GET_TEMP: val = i8k_get_temp(0); break; case I8K_GET_SPEED: if (copy_from_user(&val, argp, sizeof(int))) return -EFAULT; val = i8k_get_fan_speed(val); break; case I8K_GET_FAN: if (copy_from_user(&val, argp, sizeof(int))) return -EFAULT; val = i8k_get_fan_status(val); break; case I8K_SET_FAN: if (restricted && !capable(CAP_SYS_ADMIN)) return -EPERM; if (copy_from_user(&val, argp, sizeof(int))) return -EFAULT; if (copy_from_user(&speed, argp + 1, sizeof(int))) return -EFAULT; val = i8k_set_fan(val, speed); break; default: return -EINVAL; } if (val < 0) return val; switch (cmd) { case I8K_BIOS_VERSION: if (copy_to_user(argp, &val, 4)) return -EFAULT; break; case I8K_MACHINE_ID: if (copy_to_user(argp, buff, 16)) return -EFAULT; break; default: if (copy_to_user(argp, &val, sizeof(int))) return -EFAULT; break; } return 0; } /* * Print the information for /proc/i8k. */ static int i8k_proc_show(struct seq_file *seq, void *offset) { int fn_key, cpu_temp, ac_power; int left_fan, right_fan, left_speed, right_speed; cpu_temp = i8k_get_temp(0); /* 11100 µs */ left_fan = i8k_get_fan_status(I8K_FAN_LEFT); /* 580 µs */ right_fan = i8k_get_fan_status(I8K_FAN_RIGHT); /* 580 µs */ left_speed = i8k_get_fan_speed(I8K_FAN_LEFT); /* 580 µs */ right_speed = i8k_get_fan_speed(I8K_FAN_RIGHT); /* 580 µs */ fn_key = i8k_get_fn_status(); /* 750 µs */ if (power_status) ac_power = i8k_get_power_status(); /* 14700 µs */ else ac_power = -1; /* * Info: * * 1) Format version (this will change if format changes) * 2) BIOS version * 3) BIOS machine ID * 4) Cpu temperature * 5) Left fan status * 6) Right fan status * 7) Left fan speed * 8) Right fan speed * 9) AC power * 10) Fn Key status */ return seq_printf(seq, "%s %s %s %d %d %d %d %d %d %d\n", I8K_PROC_FMT, bios_version, i8k_get_dmi_data(DMI_PRODUCT_SERIAL), cpu_temp, left_fan, right_fan, left_speed, right_speed, ac_power, fn_key); } static int i8k_open_fs(struct inode *inode, struct file *file) { return single_open(file, i8k_proc_show, NULL); } 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"), }, }, { .ident = "Dell Inspiron 2", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "Inspiron"), }, }, { .ident = "Dell Latitude 2", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "Latitude"), }, }, { /* UK Inspiron 6400 */ .ident = "Dell Inspiron 3", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "MM061"), }, }, { .ident = "Dell Inspiron 3", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "MP061"), }, }, { .ident = "Dell Precision", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "Precision"), }, }, { .ident = "Dell Vostro", .matches = { DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), DMI_MATCH(DMI_PRODUCT_NAME, "Vostro"), }, }, { } }; /* * Probe for the presence of a supported laptop. */ static int __init i8k_probe(void) { char buff[4]; int version; /* * Get DMI information */ 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", 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(I8K_SMM_GET_DELL_SIG1) && i8k_get_dell_signature(I8K_SMM_GET_DELL_SIG2)) { printk(KERN_ERR "i8k: unable to get SMM Dell signature\n"); if (!force) return -ENODEV; } /* * Get SMM BIOS version. */ version = i8k_get_bios_version(); if (version <= 0) { printk(KERN_WARNING "i8k: unable to get SMM BIOS version\n"); } else { buff[0] = (version >> 16) & 0xff; buff[1] = (version >> 8) & 0xff; buff[2] = (version) & 0xff; buff[3] = '\0'; /* * If DMI BIOS version is unknown use SMM BIOS version. */ 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_WARNING "i8k: BIOS version mismatch: %s != %s\n", buff, bios_version); } return 0; } static int __init i8k_init(void) { struct proc_dir_entry *proc_i8k; /* Are we running on an supported laptop? */ if (i8k_probe()) return -ENODEV; /* Register the proc entry */ proc_i8k = proc_create("i8k", 0, NULL, &i8k_fops); if (!proc_i8k) return -ENOENT; printk(KERN_INFO "Dell laptop SMM driver v%s Massimo Dal Zotto (dz@debian.org)\n", I8K_VERSION); return 0; } static void __exit i8k_exit(void) { remove_proc_entry("i8k", NULL); } module_init(i8k_init); module_exit(i8k_exit);