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-rw-r--r--drivers/i2c/Makefile5
-rw-r--r--drivers/i2c/i2c-acpi.c273
-rw-r--r--drivers/i2c/i2c-core.c2
-rw-r--r--include/linux/acpi.h11
-rw-r--r--include/linux/i2c.h10
5 files changed, 300 insertions, 1 deletions
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 1722f50f2473..80db3073aa84 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -2,8 +2,11 @@
# Makefile for the i2c core.
#
+i2ccore-y := i2c-core.o
+i2ccore-$(CONFIG_ACPI) += i2c-acpi.o
+
obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o
-obj-$(CONFIG_I2C) += i2c-core.o
+obj-$(CONFIG_I2C) += i2ccore.o
obj-$(CONFIG_I2C_SMBUS) += i2c-smbus.o
obj-$(CONFIG_I2C_CHARDEV) += i2c-dev.o
obj-$(CONFIG_I2C_MUX) += i2c-mux.o
diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c
new file mode 100644
index 000000000000..f7f4c89c09b3
--- /dev/null
+++ b/drivers/i2c/i2c-acpi.c
@@ -0,0 +1,273 @@
+/*
+ * I2C ACPI code
+ *
+ * Copyright (C) 2014 Intel Corp
+ *
+ * Author: Lan Tianyu <tianyu.lan@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+#define pr_fmt(fmt) "I2C/ACPI : " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/acpi.h>
+
+struct acpi_i2c_handler_data {
+ struct acpi_connection_info info;
+ struct i2c_adapter *adapter;
+};
+
+struct gsb_buffer {
+ u8 status;
+ u8 len;
+ union {
+ u16 wdata;
+ u8 bdata;
+ u8 data[0];
+ };
+} __packed;
+
+static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
+ u8 cmd, u8 *data, u8 data_len)
+{
+
+ struct i2c_msg msgs[2];
+ int ret;
+ u8 *buffer;
+
+ buffer = kzalloc(data_len, GFP_KERNEL);
+ if (!buffer)
+ return AE_NO_MEMORY;
+
+ msgs[0].addr = client->addr;
+ msgs[0].flags = client->flags;
+ msgs[0].len = 1;
+ msgs[0].buf = &cmd;
+
+ msgs[1].addr = client->addr;
+ msgs[1].flags = client->flags | I2C_M_RD;
+ msgs[1].len = data_len;
+ msgs[1].buf = buffer;
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ dev_err(&client->adapter->dev, "i2c read failed\n");
+ else
+ memcpy(data, buffer, data_len);
+
+ kfree(buffer);
+ return ret;
+}
+
+static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
+ u8 cmd, u8 *data, u8 data_len)
+{
+
+ struct i2c_msg msgs[1];
+ u8 *buffer;
+ int ret = AE_OK;
+
+ buffer = kzalloc(data_len + 1, GFP_KERNEL);
+ if (!buffer)
+ return AE_NO_MEMORY;
+
+ buffer[0] = cmd;
+ memcpy(buffer + 1, data, data_len);
+
+ msgs[0].addr = client->addr;
+ msgs[0].flags = client->flags;
+ msgs[0].len = data_len + 1;
+ msgs[0].buf = buffer;
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ dev_err(&client->adapter->dev, "i2c write failed\n");
+
+ kfree(buffer);
+ return ret;
+}
+
+static acpi_status
+acpi_i2c_space_handler(u32 function, acpi_physical_address command,
+ u32 bits, u64 *value64,
+ void *handler_context, void *region_context)
+{
+ struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
+ struct acpi_i2c_handler_data *data = handler_context;
+ struct acpi_connection_info *info = &data->info;
+ struct acpi_resource_i2c_serialbus *sb;
+ struct i2c_adapter *adapter = data->adapter;
+ struct i2c_client client;
+ struct acpi_resource *ares;
+ u32 accessor_type = function >> 16;
+ u8 action = function & ACPI_IO_MASK;
+ acpi_status ret = AE_OK;
+ int status;
+
+ ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
+ if (ACPI_FAILURE(ret))
+ return ret;
+
+ if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ sb = &ares->data.i2c_serial_bus;
+ if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ memset(&client, 0, sizeof(client));
+ client.adapter = adapter;
+ client.addr = sb->slave_address;
+ client.flags = 0;
+
+ if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+ client.flags |= I2C_CLIENT_TEN;
+
+ switch (accessor_type) {
+ case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
+ if (action == ACPI_READ) {
+ status = i2c_smbus_read_byte(&client);
+ if (status >= 0) {
+ gsb->bdata = status;
+ status = 0;
+ }
+ } else {
+ status = i2c_smbus_write_byte(&client, gsb->bdata);
+ }
+ break;
+
+ case ACPI_GSB_ACCESS_ATTRIB_BYTE:
+ if (action == ACPI_READ) {
+ status = i2c_smbus_read_byte_data(&client, command);
+ if (status >= 0) {
+ gsb->bdata = status;
+ status = 0;
+ }
+ } else {
+ status = i2c_smbus_write_byte_data(&client, command,
+ gsb->bdata);
+ }
+ break;
+
+ case ACPI_GSB_ACCESS_ATTRIB_WORD:
+ if (action == ACPI_READ) {
+ status = i2c_smbus_read_word_data(&client, command);
+ if (status >= 0) {
+ gsb->wdata = status;
+ status = 0;
+ }
+ } else {
+ status = i2c_smbus_write_word_data(&client, command,
+ gsb->wdata);
+ }
+ break;
+
+ case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
+ if (action == ACPI_READ) {
+ status = i2c_smbus_read_block_data(&client, command,
+ gsb->data);
+ if (status >= 0) {
+ gsb->len = status;
+ status = 0;
+ }
+ } else {
+ status = i2c_smbus_write_block_data(&client, command,
+ gsb->len, gsb->data);
+ }
+ break;
+
+ case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
+ if (action == ACPI_READ) {
+ status = acpi_gsb_i2c_read_bytes(&client, command,
+ gsb->data, info->access_length);
+ if (status > 0)
+ status = 0;
+ } else {
+ status = acpi_gsb_i2c_write_bytes(&client, command,
+ gsb->data, info->access_length);
+ }
+ break;
+
+ default:
+ pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ gsb->status = status;
+
+ err:
+ ACPI_FREE(ares);
+ return ret;
+}
+
+
+int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{
+ acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
+ struct acpi_i2c_handler_data *data;
+ acpi_status status;
+
+ if (!handle)
+ return -ENODEV;
+
+ data = kzalloc(sizeof(struct acpi_i2c_handler_data),
+ GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->adapter = adapter;
+ status = acpi_bus_attach_private_data(handle, (void *)data);
+ if (ACPI_FAILURE(status)) {
+ kfree(data);
+ return -ENOMEM;
+ }
+
+ status = acpi_install_address_space_handler(handle,
+ ACPI_ADR_SPACE_GSBUS,
+ &acpi_i2c_space_handler,
+ NULL,
+ data);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&adapter->dev, "Error installing i2c space handler\n");
+ acpi_bus_detach_private_data(handle);
+ kfree(data);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{
+ acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
+ struct acpi_i2c_handler_data *data;
+ acpi_status status;
+
+ if (!handle)
+ return;
+
+ acpi_remove_address_space_handler(handle,
+ ACPI_ADR_SPACE_GSBUS,
+ &acpi_i2c_space_handler);
+
+ status = acpi_bus_get_private_data(handle, (void **)&data);
+ if (ACPI_SUCCESS(status))
+ kfree(data);
+
+ acpi_bus_detach_private_data(handle);
+}
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 7c7f4b856bad..e25cb84cb297 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -1293,6 +1293,7 @@ exit_recovery:
/* create pre-declared device nodes */
of_i2c_register_devices(adap);
acpi_i2c_register_devices(adap);
+ acpi_i2c_install_space_handler(adap);
if (adap->nr < __i2c_first_dynamic_bus_num)
i2c_scan_static_board_info(adap);
@@ -1466,6 +1467,7 @@ void i2c_del_adapter(struct i2c_adapter *adap)
return;
}
+ acpi_i2c_remove_space_handler(adap);
/* Tell drivers about this removal */
mutex_lock(&core_lock);
bus_for_each_drv(&i2c_bus_type, NULL, adap,
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 358c01b971db..40718e91e171 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -364,6 +364,17 @@ extern bool osc_sb_apei_support_acked;
#define OSC_PCI_EXPRESS_CAPABILITY_CONTROL 0x00000010
#define OSC_PCI_CONTROL_MASKS 0x0000001f
+#define ACPI_GSB_ACCESS_ATTRIB_QUICK 0x00000002
+#define ACPI_GSB_ACCESS_ATTRIB_SEND_RCV 0x00000004
+#define ACPI_GSB_ACCESS_ATTRIB_BYTE 0x00000006
+#define ACPI_GSB_ACCESS_ATTRIB_WORD 0x00000008
+#define ACPI_GSB_ACCESS_ATTRIB_BLOCK 0x0000000A
+#define ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE 0x0000000B
+#define ACPI_GSB_ACCESS_ATTRIB_WORD_CALL 0x0000000C
+#define ACPI_GSB_ACCESS_ATTRIB_BLOCK_CALL 0x0000000D
+#define ACPI_GSB_ACCESS_ATTRIB_RAW_BYTES 0x0000000E
+#define ACPI_GSB_ACCESS_ATTRIB_RAW_PROCESS 0x0000000F
+
extern acpi_status acpi_pci_osc_control_set(acpi_handle handle,
u32 *mask, u32 req);
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index b556e0ab946f..f7a939a2cb56 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -577,4 +577,14 @@ static inline struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node
}
#endif /* CONFIG_OF */
+#ifdef CONFIG_ACPI
+int acpi_i2c_install_space_handler(struct i2c_adapter *adapter);
+void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter);
+#else
+static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{ }
+static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{ return 0; }
+#endif
+
#endif /* _LINUX_I2C_H */
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