--- /dev/null
+/*
+ * 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;
+};
+
+static const struct smbus_methods_t smbus_methods = {
+ .mt_info = "_SBI",
+ .mt_sbr = "_SBR",
+ .mt_sbw = "_SBW",
+};
+
+static const struct acpi_device_id acpi_smbus_cmi_ids[] = {
+ {"SMBUS01", 0},
+ {"", 0}
+};
+
+#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_methods.mt_sbr;
+ input.count = 3;
+ } else {
+ protocol |= ACPI_SMBUS_PRTCL_WRITE;
+ method = smbus_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_methods.mt_info)) {
+ status = acpi_evaluate_object(smbus_cmi->handle,
+ smbus_methods.mt_info,
+ NULL, &buffer);
+ if (ACPI_FAILURE(status)) {
+ ACPI_ERROR((AE_INFO, "Evaluating %s: %i",
+ smbus_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_methods.mt_sbr))
+ smbus_cmi->cap_read = 1;
+ else if (!strcmp(name, smbus_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;
+
+ 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;
+
+ acpi_walk_namespace(ACPI_TYPE_METHOD, smbus_cmi->handle, 1,
+ acpi_smbus_cmi_query_methods, 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 (%s)",
+ acpi_device_name(device),
+ acpi_device_uid(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");
projects / mirror_ubuntu-zesty-kernel.git / commitdiff