thinkpad-acpi: add quirklist engine

Add a quirklist engine suitable for matching ThinkPad firmware,
and change the code to use it.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 98 insertions, 21 deletions

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index d2a0ef83fbb5..3981b060b7d5 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -364,6 +364,73 @@ static void tpacpi_log_usertask(const char * const what)
                 } \
         } while (0)
 
+/*
+ * Quirk handling helpers
+ *
+ * ThinkPad IDs and versions seen in the field so far
+ * are two-characters from the set [0-9A-Z], i.e. base 36.
+ *
+ * We use values well outside that range as specials.
+ */
+
+#define TPACPI_MATCH_ANY                0xffffU
+#define TPACPI_MATCH_UNKNOWN            0U
+
+/* TPID('1', 'Y') == 0x5931 */
+#define TPID(__c1, __c2) (((__c2) << 8) | (__c1))
+
+#define TPACPI_Q_IBM(__id1, __id2, __quirk)     \
+        { .vendor = PCI_VENDOR_ID_IBM,          \
+          .bios = TPID(__id1, __id2),           \
+          .ec = TPACPI_MATCH_ANY,               \
+          .quirks = (__quirk) }
+
+#define TPACPI_Q_LNV(__id1, __id2, __quirk)     \
+        { .vendor = PCI_VENDOR_ID_LENOVO,       \
+          .bios = TPID(__id1, __id2),           \
+          .ec = TPACPI_MATCH_ANY,               \
+          .quirks = (__quirk) }
+
+struct tpacpi_quirk {
+        unsigned int vendor;
+        u16 bios;
+        u16 ec;
+        unsigned long quirks;
+};
+
+/**
+ * tpacpi_check_quirks() - search BIOS/EC version on a list
+ * @qlist:              array of &struct tpacpi_quirk
+ * @qlist_size:         number of elements in @qlist
+ *
+ * Iterates over a quirks list until one is found that matches the
+ * ThinkPad's vendor, BIOS and EC model.
+ *
+ * Returns 0 if nothing matches, otherwise returns the quirks field of
+ * the matching &struct tpacpi_quirk entry.
+ *
+ * The match criteria is: vendor, ec and bios much match.
+ */
+static unsigned long __init tpacpi_check_quirks(
+                        const struct tpacpi_quirk *qlist,
+                        unsigned int qlist_size)
+{
+        while (qlist_size) {
+                if ((qlist->vendor == thinkpad_id.vendor ||
+                                qlist->vendor == TPACPI_MATCH_ANY) &&
+                    (qlist->bios == thinkpad_id.bios_model ||
+                                qlist->bios == TPACPI_MATCH_ANY) &&
+                    (qlist->ec == thinkpad_id.ec_model ||
+                                qlist->ec == TPACPI_MATCH_ANY))
+                        return qlist->quirks;
+
+                qlist_size--;
+                qlist++;
+        }
+        return 0;
+}
+
+
 /****************************************************************************
  ****************************************************************************
  *
@@ -6223,30 +6290,18 @@ TPACPI_HANDLE(sfan, ec, "SFAN",	/* 570 */
  * We assume 0x07 really means auto mode while this quirk is active,
  * as this is far more likely than the ThinkPad being in level 7,
  * which is only used by the firmware during thermal emergencies.
+ *
+ * Enable for TP-1Y (T43), TP-78 (R51e), TP-76 (R52),
+ * TP-70 (T43, R52), which are known to be buggy.
  */
 
-static void fan_quirk1_detect(void)
+static void fan_quirk1_setup(void)
 {
-        /* In some ThinkPads, neither the EC nor the ACPI
-         * DSDT initialize the HFSP register, and it ends up
-         * being initially set to 0x07 when it *could* be
-         * either 0x07 or 0x80.
-         *
-         * Enable for TP-1Y (T43), TP-78 (R51e),
-         * TP-76 (R52), TP-70 (T43, R52), which are known
-         * to be buggy. */
         if (fan_control_initial_status == 0x07) {
-                switch (thinkpad_id.ec_model) {
-                case 0x5931: /* TP-1Y */
-                case 0x3837: /* TP-78 */
-                case 0x3637: /* TP-76 */
-                case 0x3037: /* TP-70 */
-                        printk(TPACPI_NOTICE
-                               "fan_init: initial fan status is unknown, "
-                               "assuming it is in auto mode\n");
-                        tp_features.fan_ctrl_status_undef = 1;
-                        ;;
-                }
+                printk(TPACPI_NOTICE
+                       "fan_init: initial fan status is unknown, "
+                       "assuming it is in auto mode\n");
+                tp_features.fan_ctrl_status_undef = 1;
         }
 }
 
@@ -6804,9 +6859,27 @@ static const struct attribute_group fan_attr_group = {
         .attrs = fan_attributes,
 };
 
+#define TPACPI_FAN_Q1   0x0001
+
+#define TPACPI_FAN_QI(__id1, __id2, __quirks)   \
+        { .vendor = PCI_VENDOR_ID_IBM,          \
+          .bios = TPACPI_MATCH_ANY,             \
+          .ec = TPID(__id1, __id2),             \
+          .quirks = __quirks }
+
+static const struct tpacpi_quirk fan_quirk_table[] __initconst = {
+        TPACPI_FAN_QI('1', 'Y', TPACPI_FAN_Q1),
+        TPACPI_FAN_QI('7', '8', TPACPI_FAN_Q1),
+        TPACPI_FAN_QI('7', '6', TPACPI_FAN_Q1),
+        TPACPI_FAN_QI('7', '0', TPACPI_FAN_Q1),
+};
+
+#undef TPACPI_FAN_QI
+
 static int __init fan_init(struct ibm_init_struct *iibm)
 {
         int rc;
+        unsigned long quirks;
 
         vdbg_printk(TPACPI_DBG_INIT | TPACPI_DBG_FAN,
                         "initializing fan subdriver\n");
@@ -6823,6 +6896,9 @@ static int __init fan_init(struct ibm_init_struct *iibm)
         TPACPI_ACPIHANDLE_INIT(gfan);
         TPACPI_ACPIHANDLE_INIT(sfan);
 
+        quirks = tpacpi_check_quirks(fan_quirk_table,
+                                     ARRAY_SIZE(fan_quirk_table));
+
         if (gfan_handle) {
                 /* 570, 600e/x, 770e, 770x */
                 fan_status_access_mode = TPACPI_FAN_RD_ACPI_GFAN;
@@ -6832,7 +6908,8 @@ static int __init fan_init(struct ibm_init_struct *iibm)
                 if (likely(acpi_ec_read(fan_status_offset,
                                         &fan_control_initial_status))) {
                         fan_status_access_mode = TPACPI_FAN_RD_TPEC;
-                        fan_quirk1_detect();
+                        if (quirks & TPACPI_FAN_Q1)
+                                fan_quirk1_setup();
                 } else {
                         printk(TPACPI_ERR
                                "ThinkPad ACPI EC access misbehaving, "