i2c-scmi: Support IBM SMBus CMI devices

*) add a new HID for IBM SMBus CMI devices
*) add methods for IBM SMBus CMI devices
*) hook different HID with different control methods set
*) minor tweaks as suggested by Jean Delvare

Slightly modified by Darrick to use #define'd IBM SMBUS HID from Darrick's ACPI
scan quirk patch.

Signed-off-by: Crane Cai <crane.cai@amd.com>
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Jean Delvare <khali@linux-fr.org>

diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c
index 365e0be..4c9fb4c 100644 (file)
--- a/drivers/i2c/busses/i2c-scmi.c
+++ b/drivers/i2c/busses/i2c-scmi.c
@@ -33,6 +33,7 @@ struct acpi_smbus_cmi {
        u8 cap_info:1;
        u8 cap_read:1;
        u8 cap_write:1;
+       struct smbus_methods_t *methods;
 };
 
 static const struct smbus_methods_t smbus_methods = {
@@ -41,8 +42,16 @@ static const struct smbus_methods_t smbus_methods = {
        .mt_sbw  = "_SBW",
 };
 
+/* Some IBM BIOSes omit the leading underscore */
+static const struct smbus_methods_t ibm_smbus_methods = {
+       .mt_info = "SBI_",
+       .mt_sbr  = "SBR_",
+       .mt_sbw  = "SBW_",
+};
+
 static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
-       {"SMBUS01", 0},
+       {"SMBUS01", (kernel_ulong_t)&smbus_methods},
+       {ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods},
        {"", 0}
 };
 
@@ -150,11 +159,11 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 
        if (read_write == I2C_SMBUS_READ) {
                protocol |= ACPI_SMBUS_PRTCL_READ;
-               method = smbus_methods.mt_sbr;
+               method = smbus_cmi->methods->mt_sbr;
                input.count = 3;
        } else {
                protocol |= ACPI_SMBUS_PRTCL_WRITE;
-               method = smbus_methods.mt_sbw;
+               method = smbus_cmi->methods->mt_sbw;
                input.count = 5;
        }
 
@@ -290,13 +299,13 @@ static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
        union acpi_object *obj;
        acpi_status status;
 
-       if (!strcmp(name, smbus_methods.mt_info)) {
+       if (!strcmp(name, smbus_cmi->methods->mt_info)) {
                status = acpi_evaluate_object(smbus_cmi->handle,
-                                       smbus_methods.mt_info,
+                                       smbus_cmi->methods->mt_info,
                                        NULL, &buffer);
                if (ACPI_FAILURE(status)) {
                        ACPI_ERROR((AE_INFO, "Evaluating %s: %i",
-                                  smbus_methods.mt_info, status));
+                                  smbus_cmi->methods->mt_info, status));
                        return -EIO;
                }
 
@@ -319,9 +328,9 @@ static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi,
 
                kfree(buffer.pointer);
                smbus_cmi->cap_info = 1;
-       } else if (!strcmp(name, smbus_methods.mt_sbr))
+       } else if (!strcmp(name, smbus_cmi->methods->mt_sbr))
                smbus_cmi->cap_read = 1;
-       else if (!strcmp(name, smbus_methods.mt_sbw))
+       else if (!strcmp(name, smbus_cmi->methods->mt_sbw))
                smbus_cmi->cap_write = 1;
        else
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Unsupported CMI method: %s\n",
@@ -349,6 +358,7 @@ static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level,
 static int acpi_smbus_cmi_add(struct acpi_device *device)
 {
        struct acpi_smbus_cmi *smbus_cmi;
+       const struct acpi_device_id *id;
 
        smbus_cmi = kzalloc(sizeof(struct acpi_smbus_cmi), GFP_KERNEL);
        if (!smbus_cmi)
@@ -362,6 +372,11 @@ static int acpi_smbus_cmi_add(struct acpi_device *device)
        smbus_cmi->cap_read = 0;
        smbus_cmi->cap_write = 0;
 
+       for (id = acpi_smbus_cmi_ids; id->id[0]; id++)
+               if (!strcmp(id->id, acpi_device_hid(device)))
+                       smbus_cmi->methods =
+                               (struct smbus_methods_t *) id->driver_data;
+
        acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
                            acpi_smbus_cmi_query_methods, NULL, smbus_cmi, NULL);