/* * SMBus driver for ACPI SMBus CMI * * Copyright (C) 2009 Crane Cai <crane.cai@amd.com> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation version 2. */ #include <linux/module.h> #include <linux/slab.h> #include <linux/kernel.h> #include <linux/stddef.h> #include <linux/init.h> #include <linux/i2c.h> #include <linux/acpi.h> #define ACPI_SMBUS_HC_CLASS "smbus" #define ACPI_SMBUS_HC_DEVICE_NAME "cmi" ACPI_MODULE_NAME("smbus_cmi"); struct smbus_methods_t { char *mt_info; char *mt_sbr; char *mt_sbw; }; struct acpi_smbus_cmi { acpi_handle handle; struct i2c_adapter adapter; 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 = { .mt_info = "_SBI", .mt_sbr = "_SBR", .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", (kernel_ulong_t)&smbus_methods}, {ACPI_SMBUS_IBM_HID, (kernel_ulong_t)&ibm_smbus_methods}, {"", 0} }; MODULE_DEVICE_TABLE(acpi, acpi_smbus_cmi_ids); #define ACPI_SMBUS_STATUS_OK 0x00 #define ACPI_SMBUS_STATUS_FAIL 0x07 #define ACPI_SMBUS_STATUS_DNAK 0x10 #define ACPI_SMBUS_STATUS_DERR 0x11 #define ACPI_SMBUS_STATUS_CMD_DENY 0x12 #define ACPI_SMBUS_STATUS_UNKNOWN 0x13 #define ACPI_SMBUS_STATUS_ACC_DENY 0x17 #define ACPI_SMBUS_STATUS_TIMEOUT 0x18 #define ACPI_SMBUS_STATUS_NOTSUP 0x19 #define ACPI_SMBUS_STATUS_BUSY 0x1a #define ACPI_SMBUS_STATUS_PEC 0x1f #define ACPI_SMBUS_PRTCL_WRITE 0x00 #define ACPI_SMBUS_PRTCL_READ 0x01 #define ACPI_SMBUS_PRTCL_QUICK 0x02 #define ACPI_SMBUS_PRTCL_BYTE 0x04 #define ACPI_SMBUS_PRTCL_BYTE_DATA 0x06 #define ACPI_SMBUS_PRTCL_WORD_DATA 0x08 #define ACPI_SMBUS_PRTCL_BLOCK_DATA 0x0a static int acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags, char read_write, u8 command, int size, union i2c_smbus_data *data) { int result = 0; struct acpi_smbus_cmi *smbus_cmi = adap->algo_data; unsigned char protocol; acpi_status status = 0; struct acpi_object_list input; union acpi_object mt_params[5]; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *obj; union acpi_object *pkg; char *method; int len = 0; dev_dbg(&adap->dev, "access size: %d %s\n", size, (read_write) ? "READ" : "WRITE"); switch (size) { case I2C_SMBUS_QUICK: protocol = ACPI_SMBUS_PRTCL_QUICK; command = 0; if (read_write == I2C_SMBUS_WRITE) { mt_params[3].type = ACPI_TYPE_INTEGER; mt_params[3].integer.value = 0; mt_params[4].type = ACPI_TYPE_INTEGER; mt_params[4].integer.value = 0; } break; case I2C_SMBUS_BYTE: protocol = ACPI_SMBUS_PRTCL_BYTE; if (read_write == I2C_SMBUS_WRITE) { mt_params[3].type = ACPI_TYPE_INTEGER; mt_params[3].integer.value = 0; mt_params[4].type = ACPI_TYPE_INTEGER; mt_params[4].integer.value = 0; } else { command = 0; } break; case I2C_SMBUS_BYTE_DATA: protocol = ACPI_SMBUS_PRTCL_BYTE_DATA; if (read_write == I2C_SMBUS_WRITE) { mt_params[3].type = ACPI_TYPE_INTEGER; mt_params[3].integer.value = 1; mt_params[4].type = ACPI_TYPE_INTEGER; mt_params[4].integer.value = data->byte; } break; case I2C_SMBUS_WORD_DATA: protocol = ACPI_SMBUS_PRTCL_WORD_DATA; if (read_write == I2C_SMBUS_WRITE) { mt_params[3].type = ACPI_TYPE_INTEGER; mt_params[3].integer.value = 2; mt_params[4].type = ACPI_TYPE_INTEGER; mt_params[4].integer.value = data->word; } break; case I2C_SMBUS_BLOCK_DATA: protocol = ACPI_SMBUS_PRTCL_BLOCK_DATA; if (read_write == I2C_SMBUS_WRITE) { len = data->block[0]; if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) return -EINVAL; mt_params[3].type = ACPI_TYPE_INTEGER; mt_params[3].integer.value = len; mt_params[4].type = ACPI_TYPE_BUFFER; mt_params[4].buffer.pointer = data->block + 1; } break; default: dev_warn(&adap->dev, "Unsupported transaction %d\n", size); return -EOPNOTSUPP; } if (read_write == I2C_SMBUS_READ) { protocol |= ACPI_SMBUS_PRTCL_READ; method = smbus_cmi->methods->mt_sbr; input.count = 3; } else { protocol |= ACPI_SMBUS_PRTCL_WRITE; method = smbus_cmi->methods->mt_sbw; input.count = 5; } input.pointer = mt_params; mt_params[0].type = ACPI_TYPE_INTEGER; mt_params[0].integer.value = protocol; mt_params[1].type = ACPI_TYPE_INTEGER; mt_params[1].integer.value = addr; mt_params[2].type = ACPI_TYPE_INTEGER; mt_params[2].integer.value = command; status = acpi_evaluate_object(smbus_cmi->handle, method, &input, &buffer); if (ACPI_FAILURE(status)) { ACPI_ERROR((AE_INFO, "Evaluating %s: %i", method, status)); return -EIO; } pkg = buffer.pointer; if (pkg && pkg->type == ACPI_TYPE_PACKAGE) obj = pkg->package.elements; else { ACPI_ERROR((AE_INFO, "Invalid argument type")); result = -EIO; goto out; } if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) { ACPI_ERROR((AE_INFO, "Invalid argument type")); result = -EIO; goto out; } result = obj->integer.value; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "%s return status: %i\n", method, result)); switch (result) { case ACPI_SMBUS_STATUS_OK: result = 0; break; case ACPI_SMBUS_STATUS_BUSY: result = -EBUSY; goto out; case ACPI_SMBUS_STATUS_TIMEOUT: result = -ETIMEDOUT; goto out; case ACPI_SMBUS_STATUS_DNAK: result = -ENXIO; goto out; default: result = -EIO; goto out; } if (read_write == I2C_SMBUS_WRITE || size == I2C_SMBUS_QUICK) goto out; obj = pkg->package.elements + 1; if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) { ACPI_ERROR((AE_INFO, "Invalid argument type")); result = -EIO; goto out; } len = obj->integer.value; obj = pkg->package.elements + 2; switch (size) { case I2C_SMBUS_BYTE: case I2C_SMBUS_BYTE_DATA: case I2C_SMBUS_WORD_DATA: if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) { ACPI_ERROR((AE_INFO, "Invalid argument type")); result = -EIO; goto out; } if (len == 2) data->word = obj->integer.value; else data->byte = obj->integer.value; break; case I2C_SMBUS_BLOCK_DATA: if (obj == NULL || obj->type != ACPI_TYPE_BUFFER) { ACPI_ERROR((AE_INFO, "Invalid argument type")); result = -EIO; goto out; } if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) return -EPROTO; data->block[0] = len; memcpy(data->block + 1, obj->buffer.pointer, len); break; } out: kfree(buffer.pointer); dev_dbg(&adap->dev, "Transaction status: %i\n", result); return result; } static u32 acpi_smbus_cmi_func(struct i2c_adapter *adapter) { struct acpi_smbus_cmi *smbus_cmi = adapter->algo_data; u32 ret; ret = smbus_cmi->cap_read | smbus_cmi->cap_write ? I2C_FUNC_SMBUS_QUICK : 0; ret |= smbus_cmi->cap_read ? (I2C_FUNC_SMBUS_READ_BYTE | I2C_FUNC_SMBUS_READ_BYTE_DATA | I2C_FUNC_SMBUS_READ_WORD_DATA | I2C_FUNC_SMBUS_READ_BLOCK_DATA) : 0; ret |= smbus_cmi->cap_write ? (I2C_FUNC_SMBUS_WRITE_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE_DATA | I2C_FUNC_SMBUS_WRITE_WORD_DATA | I2C_FUNC_SMBUS_WRITE_BLOCK_DATA) : 0; return ret; } static const struct i2c_algorithm acpi_smbus_cmi_algorithm = { .smbus_xfer = acpi_smbus_cmi_access, .functionality = acpi_smbus_cmi_func, }; static int acpi_smbus_cmi_add_cap(struct acpi_smbus_cmi *smbus_cmi, const char *name) { struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *obj; acpi_status status; if (!strcmp(name, smbus_cmi->methods->mt_info)) { status = acpi_evaluate_object(smbus_cmi->handle, smbus_cmi->methods->mt_info, NULL, &buffer); if (ACPI_FAILURE(status)) { ACPI_ERROR((AE_INFO, "Evaluating %s: %i", smbus_cmi->methods->mt_info, status)); return -EIO; } obj = buffer.pointer; if (obj && obj->type == ACPI_TYPE_PACKAGE) obj = obj->package.elements; else { ACPI_ERROR((AE_INFO, "Invalid argument type")); kfree(buffer.pointer); return -EIO; } if (obj->type != ACPI_TYPE_INTEGER) { ACPI_ERROR((AE_INFO, "Invalid argument type")); kfree(buffer.pointer); return -EIO; } else ACPI_DEBUG_PRINT((ACPI_DB_INFO, "SMBus CMI Version %x" "\n", (int)obj->integer.value)); kfree(buffer.pointer); smbus_cmi->cap_info = 1; } else if (!strcmp(name, smbus_cmi->methods->mt_sbr)) smbus_cmi->cap_read = 1; 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", name)); return 0; } static acpi_status acpi_smbus_cmi_query_methods(acpi_handle handle, u32 level, void *context, void **return_value) { char node_name[5]; struct acpi_buffer buffer = { sizeof(node_name), node_name }; struct acpi_smbus_cmi *smbus_cmi = context; acpi_status status; status = acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer); if (ACPI_SUCCESS(status)) acpi_smbus_cmi_add_cap(smbus_cmi, node_name); return AE_OK; } 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) return -ENOMEM; smbus_cmi->handle = device->handle; strcpy(acpi_device_name(device), ACPI_SMBUS_HC_DEVICE_NAME); strcpy(acpi_device_class(device), ACPI_SMBUS_HC_CLASS); device->driver_data = smbus_cmi; smbus_cmi->cap_info = 0; 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); if (smbus_cmi->cap_info == 0) goto err; snprintf(smbus_cmi->adapter.name, sizeof(smbus_cmi->adapter.name), "SMBus CMI adapter %s", acpi_device_name(device)); smbus_cmi->adapter.owner = THIS_MODULE; smbus_cmi->adapter.algo = &acpi_smbus_cmi_algorithm; smbus_cmi->adapter.algo_data = smbus_cmi; smbus_cmi->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD; smbus_cmi->adapter.dev.parent = &device->dev; if (i2c_add_adapter(&smbus_cmi->adapter)) { dev_err(&device->dev, "Couldn't register adapter!\n"); goto err; } return 0; err: kfree(smbus_cmi); device->driver_data = NULL; return -EIO; } static int acpi_smbus_cmi_remove(struct acpi_device *device, int type) { struct acpi_smbus_cmi *smbus_cmi = acpi_driver_data(device); i2c_del_adapter(&smbus_cmi->adapter); kfree(smbus_cmi); device->driver_data = NULL; return 0; } static struct acpi_driver acpi_smbus_cmi_driver = { .name = ACPI_SMBUS_HC_DEVICE_NAME, .class = ACPI_SMBUS_HC_CLASS, .ids = acpi_smbus_cmi_ids, .ops = { .add = acpi_smbus_cmi_add, .remove = acpi_smbus_cmi_remove, }, }; static int __init acpi_smbus_cmi_init(void) { return acpi_bus_register_driver(&acpi_smbus_cmi_driver); } static void __exit acpi_smbus_cmi_exit(void) { acpi_bus_unregister_driver(&acpi_smbus_cmi_driver); } module_init(acpi_smbus_cmi_init); module_exit(acpi_smbus_cmi_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Crane Cai <crane.cai@amd.com>"); MODULE_DESCRIPTION("ACPI SMBus CMI driver");