diff options
Diffstat (limited to 'sys/dev')
| -rw-r--r-- | sys/dev/i2c/i2c_scan.c | 43 |
1 files changed, 39 insertions, 4 deletions
diff --git a/sys/dev/i2c/i2c_scan.c b/sys/dev/i2c/i2c_scan.c index 9a7ab32e54f..1338cb22f5f 100644 --- a/sys/dev/i2c/i2c_scan.c +++ b/sys/dev/i2c/i2c_scan.c @@ -1,4 +1,4 @@ -/* $OpenBSD: i2c_scan.c,v 1.34 2005/12/29 01:25:31 deraadt Exp $ */ +/* $OpenBSD: i2c_scan.c,v 1.35 2005/12/29 09:20:04 deraadt Exp $ */ /* * Copyright (c) 2005 Theo de Raadt <deraadt@openbsd.org> @@ -52,6 +52,22 @@ u_int8_t probereg[] = { 0x58, 0xfe, 0xff }; +/* + * Some Maxim 1617 clones MAY NOT even read cmd 0xfc! When it is + * read, they will power-on-reset. Their default condition + * (control register bit 0x80) therefore will be that they assert + * /ALERT for the 5 potential errors that may occur. One of those + * errors is that the external temperature diode is missing. This + * is unfortunately a common choice of system designers, except + * suddenly now we get a /ALERT, which may on some chipsets cause + * us to receive an entirely unexpected SMI .. and then an NMI. + * + * As we probe each device, if we hit something which looks suspiciously + * like it may potentially be a 1617 or clone, we immediately set this + * variable to avoid reading that register offset. + */ +int skip_fc; + static i2c_tag_t probe_ic; static u_int8_t probe_addr; static u_int8_t probe_val[256]; @@ -75,6 +91,12 @@ iicprobenc(u_int8_t cmd) { u_int8_t data; + /* + * If we think we are talking to an evil Maxim 1617 or clone, + * avoid accessing this register because it is death. + */ + if (skip_fc && cmd == 0xfc) + return (0xff); probe_ic->ic_acquire_bus(probe_ic->ic_cookie, I2C_F_POLL); if (iic_exec(probe_ic, I2C_OP_READ_WITH_STOP, probe_addr, &cmd, 1, &data, 1, I2C_F_POLL) != 0) @@ -88,6 +110,12 @@ iicprobew(u_int8_t cmd) { u_int16_t data2; + /* + * If we think we are talking to an evil Maxim 1617 or clone, + * avoid accessing this register because it is death. + */ + if (skip_fc && cmd == 0xfc) + return (0xffff); probe_ic->ic_acquire_bus(probe_ic->ic_cookie, I2C_F_POLL); if (iic_exec(probe_ic, I2C_OP_READ_WITH_STOP, probe_addr, &cmd, 1, &data2, 2, I2C_F_POLL) != 0) @@ -174,7 +202,7 @@ xeonprobe(u_int8_t addr) if (zero > 6 || copy > 6) return (NULL); val = iicprobe(0x09); - for (reg = 0x0a; reg < 0xfe; reg++) { + for (reg = 0x0a; reg < 0xfc; reg++) { if (iicprobe(reg) != val) return (NULL); } @@ -211,6 +239,7 @@ iic_probe(struct device *self, struct i2cbus_attach_args *iba, u_int8_t addr) return; iicprobeinit(iba, addr); + skip_fc = 0; switch (iicprobe(0x3e)) { case 0x41: @@ -372,11 +401,13 @@ iic_probe(struct device *self, struct i2cbus_attach_args *iba, u_int8_t addr) } else if (iicprobe(0xfe) == 0x41 && (addr == 0x4c || addr == 0x4d) && (iicprobe(0x03) & 0x2a) == 0 && iicprobe(0x04) <= 0x09) { name = "adm1032"; + skip_fc = 1; } else if (iicprobe(0xfe) == 0x41 && iicprobe(0x3c) == 0x00 && (addr == 0x18 || addr == 0x19 || addr == 0x1a || addr == 0x29 || addr == 0x2a || addr == 0x2b || addr == 0x4c || addr == 0x4d || addr == 0x4e)) { name = "adm1021"; /* lots of addresses... bleah */ + skip_fc = 1; } else if (iicprobe(0x4f) == 0x5c && (iicprobe(0x4e) & 0x80)) { /* * We should toggle 0x4e bit 0x80, then re-read @@ -392,17 +423,21 @@ iic_probe(struct device *self, struct i2cbus_attach_args *iba, u_int8_t addr) #ifdef __i386__ } else if (name == NULL) { name = xeonprobe(addr); + if (name) + skip_fc = 1; #endif } #ifdef I2C_DEBUG printf("%s: addr 0x%x", self->dv_xname, addr); -// for (i = 0; i < sizeof(probereg); i++) +// for (i = 0; i < sizeof(probereg); i++) { // if (iicprobe(probereg[i]) != 0xff) // printf(" %02x=%02x", probereg[i], iicprobe(probereg[i])); - for (i = 0; i <= 0xff; i++) +// } + for (i = 0; i <= 0xff; i++) { if (iicprobe(i) != 0xff) printf(" %02x=%02x", i, iicprobe(i)); + } if (name) printf(": %s", name); printf("\n"); |