From e521d069115dd1654844d450a427aade79a87a5e Mon Sep 17 00:00:00 2001 Message-Id: From: Jani Nikula Date: Tue, 30 Apr 2013 12:09:45 +0300 Subject: [PATCH 1/2] dmi: add support for exact DMI matches in addition to substring matching Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Cc: Jani Nikula dmi_match() considers a substring match to be a successful match. This is not always sufficient to distinguish between DMI data for different systems. Add support for exact string matching using strcmp() in addition to the substring matching using strstr(). The specific use case in the i915 driver is to allow us to use an exact match for D510MO, without also incorrectly matching D510MOV: { .ident = "Intel D510MO", .matches = { DMI_MATCH(DMI_BOARD_VENDOR, "Intel"), DMI_EXACT_MATCH(DMI_BOARD_NAME, "D510MO"), }, } Signed-off-by: Jani Nikula --- drivers/firmware/dmi_scan.c | 12 +++++++++--- include/linux/mod_devicetable.h | 6 ++++-- 2 files changed, 13 insertions(+), 5 deletions(-) diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index 4cd392d..2861ef4 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -534,9 +534,15 @@ static bool dmi_matches(const struct dmi_system_id *dmi) int s = dmi->matches[i].slot; if (s == DMI_NONE) break; - if (dmi_ident[s] - && strstr(dmi_ident[s], dmi->matches[i].substr)) - continue; + if (dmi_ident[s]) { + if (!dmi->matches[i].exact_match && + strstr(dmi_ident[s], dmi->matches[i].substr)) + continue; + else if (dmi->matches[i].exact_match && + !strcmp(dmi_ident[s], dmi->matches[i].substr)) + continue; + } + /* No match */ return false; } diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index 779cf7c..90be3f1 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -455,7 +455,8 @@ enum dmi_field { }; struct dmi_strmatch { - unsigned char slot; + unsigned char slot:7; + unsigned char exact_match:1; char substr[79]; }; @@ -473,7 +474,8 @@ struct dmi_system_id { */ #define dmi_device_id dmi_system_id -#define DMI_MATCH(a, b) { a, b } +#define DMI_MATCH(a, b) { .slot = a, .substr = b } +#define DMI_EXACT_MATCH(a, b) { .slot = a, .substr = b, .exact_match = 1 } #define PLATFORM_NAME_SIZE 20 #define PLATFORM_MODULE_PREFIX "platform:" -- 1.7.10.4