linux/drivers/i2c/busses/i2c-opal.c
Thomas Gleixner d5bb994bcd treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 114
Based on 1 normalized pattern(s):

  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 either version 2 of the license or at
  your option any later version 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 you
  should have received a copy of the gnu general public license along
  with this program

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 8 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190523091650.663497195@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:39:01 +02:00

279 lines
6.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* IBM OPAL I2C driver
* Copyright (C) 2014 IBM
*/
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <asm/firmware.h>
#include <asm/opal.h>
static int i2c_opal_translate_error(int rc)
{
switch (rc) {
case OPAL_NO_MEM:
return -ENOMEM;
case OPAL_PARAMETER:
return -EINVAL;
case OPAL_I2C_ARBT_LOST:
return -EAGAIN;
case OPAL_I2C_TIMEOUT:
return -ETIMEDOUT;
case OPAL_I2C_NACK_RCVD:
return -ENXIO;
case OPAL_I2C_STOP_ERR:
return -EBUSY;
default:
return -EIO;
}
}
static int i2c_opal_send_request(u32 bus_id, struct opal_i2c_request *req)
{
struct opal_msg msg;
int token, rc;
token = opal_async_get_token_interruptible();
if (token < 0) {
if (token != -ERESTARTSYS)
pr_err("Failed to get the async token\n");
return token;
}
rc = opal_i2c_request(token, bus_id, req);
if (rc != OPAL_ASYNC_COMPLETION) {
rc = i2c_opal_translate_error(rc);
goto exit;
}
rc = opal_async_wait_response(token, &msg);
if (rc)
goto exit;
rc = opal_get_async_rc(msg);
if (rc != OPAL_SUCCESS) {
rc = i2c_opal_translate_error(rc);
goto exit;
}
exit:
opal_async_release_token(token);
return rc;
}
static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
int num)
{
unsigned long opal_id = (unsigned long)adap->algo_data;
struct opal_i2c_request req;
int rc, i;
/* We only support fairly simple combinations here of one
* or two messages
*/
memset(&req, 0, sizeof(req));
switch(num) {
case 1:
req.type = (msgs[0].flags & I2C_M_RD) ?
OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE;
req.addr = cpu_to_be16(msgs[0].addr);
req.size = cpu_to_be32(msgs[0].len);
req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf));
break;
case 2:
req.type = (msgs[1].flags & I2C_M_RD) ?
OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
req.addr = cpu_to_be16(msgs[0].addr);
req.subaddr_sz = msgs[0].len;
for (i = 0; i < msgs[0].len; i++)
req.subaddr = (req.subaddr << 8) | msgs[0].buf[i];
req.subaddr = cpu_to_be32(req.subaddr);
req.size = cpu_to_be32(msgs[1].len);
req.buffer_ra = cpu_to_be64(__pa(msgs[1].buf));
break;
}
rc = i2c_opal_send_request(opal_id, &req);
if (rc)
return rc;
return num;
}
static int i2c_opal_smbus_xfer(struct i2c_adapter *adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size, union i2c_smbus_data *data)
{
unsigned long opal_id = (unsigned long)adap->algo_data;
struct opal_i2c_request req;
u8 local[2];
int rc;
memset(&req, 0, sizeof(req));
req.addr = cpu_to_be16(addr);
switch (size) {
case I2C_SMBUS_BYTE:
req.buffer_ra = cpu_to_be64(__pa(&data->byte));
req.size = cpu_to_be32(1);
/* Fall through */
case I2C_SMBUS_QUICK:
req.type = (read_write == I2C_SMBUS_READ) ?
OPAL_I2C_RAW_READ : OPAL_I2C_RAW_WRITE;
break;
case I2C_SMBUS_BYTE_DATA:
req.buffer_ra = cpu_to_be64(__pa(&data->byte));
req.size = cpu_to_be32(1);
req.subaddr = cpu_to_be32(command);
req.subaddr_sz = 1;
req.type = (read_write == I2C_SMBUS_READ) ?
OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
break;
case I2C_SMBUS_WORD_DATA:
if (!read_write) {
local[0] = data->word & 0xff;
local[1] = (data->word >> 8) & 0xff;
}
req.buffer_ra = cpu_to_be64(__pa(local));
req.size = cpu_to_be32(2);
req.subaddr = cpu_to_be32(command);
req.subaddr_sz = 1;
req.type = (read_write == I2C_SMBUS_READ) ?
OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
break;
case I2C_SMBUS_I2C_BLOCK_DATA:
req.buffer_ra = cpu_to_be64(__pa(&data->block[1]));
req.size = cpu_to_be32(data->block[0]);
req.subaddr = cpu_to_be32(command);
req.subaddr_sz = 1;
req.type = (read_write == I2C_SMBUS_READ) ?
OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE;
break;
default:
return -EINVAL;
}
rc = i2c_opal_send_request(opal_id, &req);
if (!rc && read_write && size == I2C_SMBUS_WORD_DATA) {
data->word = ((u16)local[1]) << 8;
data->word |= local[0];
}
return rc;
}
static u32 i2c_opal_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_I2C_BLOCK;
}
static const struct i2c_algorithm i2c_opal_algo = {
.master_xfer = i2c_opal_master_xfer,
.smbus_xfer = i2c_opal_smbus_xfer,
.functionality = i2c_opal_func,
};
/*
* For two messages, we basically support simple smbus transactions of a
* write-then-anything.
*/
static const struct i2c_adapter_quirks i2c_opal_quirks = {
.flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR,
.max_comb_1st_msg_len = 4,
};
static int i2c_opal_probe(struct platform_device *pdev)
{
struct i2c_adapter *adapter;
const char *pname;
u32 opal_id;
int rc;
if (!pdev->dev.of_node)
return -ENODEV;
rc = of_property_read_u32(pdev->dev.of_node, "ibm,opal-id", &opal_id);
if (rc) {
dev_err(&pdev->dev, "Missing ibm,opal-id property !\n");
return -EIO;
}
adapter = devm_kzalloc(&pdev->dev, sizeof(*adapter), GFP_KERNEL);
if (!adapter)
return -ENOMEM;
adapter->algo = &i2c_opal_algo;
adapter->algo_data = (void *)(unsigned long)opal_id;
adapter->quirks = &i2c_opal_quirks;
adapter->dev.parent = &pdev->dev;
adapter->dev.of_node = of_node_get(pdev->dev.of_node);
pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);
if (pname)
strlcpy(adapter->name, pname, sizeof(adapter->name));
else
strlcpy(adapter->name, "opal", sizeof(adapter->name));
platform_set_drvdata(pdev, adapter);
rc = i2c_add_adapter(adapter);
if (rc)
dev_err(&pdev->dev, "Failed to register the i2c adapter\n");
return rc;
}
static int i2c_opal_remove(struct platform_device *pdev)
{
struct i2c_adapter *adapter = platform_get_drvdata(pdev);
i2c_del_adapter(adapter);
return 0;
}
static const struct of_device_id i2c_opal_of_match[] = {
{
.compatible = "ibm,opal-i2c",
},
{ }
};
MODULE_DEVICE_TABLE(of, i2c_opal_of_match);
static struct platform_driver i2c_opal_driver = {
.probe = i2c_opal_probe,
.remove = i2c_opal_remove,
.driver = {
.name = "i2c-opal",
.of_match_table = i2c_opal_of_match,
},
};
static int __init i2c_opal_init(void)
{
if (!firmware_has_feature(FW_FEATURE_OPAL))
return -ENODEV;
return platform_driver_register(&i2c_opal_driver);
}
module_init(i2c_opal_init);
static void __exit i2c_opal_exit(void)
{
return platform_driver_unregister(&i2c_opal_driver);
}
module_exit(i2c_opal_exit);
MODULE_AUTHOR("Neelesh Gupta <neelegup@linux.vnet.ibm.com>");
MODULE_DESCRIPTION("IBM OPAL I2C driver");
MODULE_LICENSE("GPL");