Commit a412ae3f authored by Darrick J. Wong's avatar Darrick J. Wong Committed by Linus Torvalds

ics932s401: new clock generator chip driver

The ics932s401 is a clock generator chip.  This driver allows users to
read the current clock outputs.
Signed-off-by: default avatarDarrick J. Wong <djwong@us.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent c0b4e3ab
Kernel driver ics932s401
======================
Supported chips:
* IDT ICS932S401
Prefix: 'ics932s401'
Addresses scanned: I2C 0x69
Datasheet: Publically available at the IDT website
Author: Darrick J. Wong
Description
-----------
This driver implements support for the IDT ICS932S401 chip family.
This chip has 4 clock outputs--a base clock for the CPU (which is likely
multiplied to get the real CPU clock), a system clock, a PCI clock, a USB
clock, and a reference clock. The driver reports selected and actual
frequency. If spread spectrum mode is enabled, the driver also reports by what
percent the clock signal is being spread, which should be between 0 and -0.5%.
All frequencies are reported in KHz.
The ICS932S401 monitors all inputs continuously. The driver will not read
the registers more often than once every other second.
Special Features
----------------
The clocks could be reprogrammed to increase system speed. I will not help you
do this, as you risk damaging your system!
...@@ -227,6 +227,16 @@ config HP_WMI ...@@ -227,6 +227,16 @@ config HP_WMI
To compile this driver as a module, choose M here: the module will To compile this driver as a module, choose M here: the module will
be called hp-wmi. be called hp-wmi.
config ICS932S401
tristate "Integrated Circuits ICS932S401"
depends on I2C && EXPERIMENTAL
help
If you say yes here you get support for the Integrated Circuits
ICS932S401 clock control chips.
This driver can also be built as a module. If so, the module
will be called ics932s401.
config MSI_LAPTOP config MSI_LAPTOP
tristate "MSI Laptop Extras" tristate "MSI Laptop Extras"
depends on X86 depends on X86
......
...@@ -14,6 +14,7 @@ obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o ...@@ -14,6 +14,7 @@ obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o
obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o
obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o
obj-$(CONFIG_HP_WMI) += hp-wmi.o obj-$(CONFIG_HP_WMI) += hp-wmi.o
obj-$(CONFIG_ICS932S401) += ics932s401.o
obj-$(CONFIG_TC1100_WMI) += tc1100-wmi.o obj-$(CONFIG_TC1100_WMI) += tc1100-wmi.o
obj-$(CONFIG_LKDTM) += lkdtm.o obj-$(CONFIG_LKDTM) += lkdtm.o
obj-$(CONFIG_TIFM_CORE) += tifm_core.o obj-$(CONFIG_TIFM_CORE) += tifm_core.o
......
/*
* A driver for the Integrated Circuits ICS932S401
* Copyright (C) 2008 IBM
*
* Author: Darrick J. Wong <djwong@us.ibm.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; 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; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/log2.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x69, I2C_CLIENT_END };
/* Insmod parameters */
I2C_CLIENT_INSMOD_1(ics932s401);
/* ICS932S401 registers */
#define ICS932S401_REG_CFG2 0x01
#define ICS932S401_CFG1_SPREAD 0x01
#define ICS932S401_REG_CFG7 0x06
#define ICS932S401_FS_MASK 0x07
#define ICS932S401_REG_VENDOR_REV 0x07
#define ICS932S401_VENDOR 1
#define ICS932S401_VENDOR_MASK 0x0F
#define ICS932S401_REV 4
#define ICS932S401_REV_SHIFT 4
#define ICS932S401_REG_DEVICE 0x09
#define ICS932S401_DEVICE 11
#define ICS932S401_REG_CTRL 0x0A
#define ICS932S401_MN_ENABLED 0x80
#define ICS932S401_CPU_ALT 0x04
#define ICS932S401_SRC_ALT 0x08
#define ICS932S401_REG_CPU_M_CTRL 0x0B
#define ICS932S401_M_MASK 0x3F
#define ICS932S401_REG_CPU_N_CTRL 0x0C
#define ICS932S401_REG_CPU_SPREAD1 0x0D
#define ICS932S401_REG_CPU_SPREAD2 0x0E
#define ICS932S401_SPREAD_MASK 0x7FFF
#define ICS932S401_REG_SRC_M_CTRL 0x0F
#define ICS932S401_REG_SRC_N_CTRL 0x10
#define ICS932S401_REG_SRC_SPREAD1 0x11
#define ICS932S401_REG_SRC_SPREAD2 0x12
#define ICS932S401_REG_CPU_DIVISOR 0x13
#define ICS932S401_CPU_DIVISOR_SHIFT 4
#define ICS932S401_REG_PCISRC_DIVISOR 0x14
#define ICS932S401_SRC_DIVISOR_MASK 0x0F
#define ICS932S401_PCI_DIVISOR_SHIFT 4
/* Base clock is 14.318MHz */
#define BASE_CLOCK 14318
#define NUM_REGS 21
#define NUM_MIRRORED_REGS 15
static int regs_to_copy[NUM_MIRRORED_REGS] = {
ICS932S401_REG_CFG2,
ICS932S401_REG_CFG7,
ICS932S401_REG_VENDOR_REV,
ICS932S401_REG_DEVICE,
ICS932S401_REG_CTRL,
ICS932S401_REG_CPU_M_CTRL,
ICS932S401_REG_CPU_N_CTRL,
ICS932S401_REG_CPU_SPREAD1,
ICS932S401_REG_CPU_SPREAD2,
ICS932S401_REG_SRC_M_CTRL,
ICS932S401_REG_SRC_N_CTRL,
ICS932S401_REG_SRC_SPREAD1,
ICS932S401_REG_SRC_SPREAD2,
ICS932S401_REG_CPU_DIVISOR,
ICS932S401_REG_PCISRC_DIVISOR,
};
/* How often do we reread sensors values? (In jiffies) */
#define SENSOR_REFRESH_INTERVAL (2 * HZ)
/* How often do we reread sensor limit values? (In jiffies) */
#define LIMIT_REFRESH_INTERVAL (60 * HZ)
struct ics932s401_data {
struct attribute_group attrs;
struct mutex lock;
char sensors_valid;
unsigned long sensors_last_updated; /* In jiffies */
u8 regs[NUM_REGS];
};
static int ics932s401_probe(struct i2c_client *client,
const struct i2c_device_id *id);
static int ics932s401_detect(struct i2c_client *client, int kind,
struct i2c_board_info *info);
static int ics932s401_remove(struct i2c_client *client);
static const struct i2c_device_id ics932s401_id[] = {
{ "ics932s401", ics932s401 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ics932s401_id);
static struct i2c_driver ics932s401_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "ics932s401",
},
.probe = ics932s401_probe,
.remove = ics932s401_remove,
.id_table = ics932s401_id,
.detect = ics932s401_detect,
.address_data = &addr_data,
};
static struct ics932s401_data *ics932s401_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct ics932s401_data *data = i2c_get_clientdata(client);
unsigned long local_jiffies = jiffies;
int i, temp;
mutex_lock(&data->lock);
if (time_before(local_jiffies, data->sensors_last_updated +
SENSOR_REFRESH_INTERVAL)
&& data->sensors_valid)
goto out;
/*
* Each register must be read as a word and then right shifted 8 bits.
* Not really sure why this is; setting the "byte count programming"
* register to 1 does not fix this problem.
*/
for (i = 0; i < NUM_MIRRORED_REGS; i++) {
temp = i2c_smbus_read_word_data(client, regs_to_copy[i]);
data->regs[regs_to_copy[i]] = temp >> 8;
}
data->sensors_last_updated = local_jiffies;
data->sensors_valid = 1;
out:
mutex_unlock(&data->lock);
return data;
}
static ssize_t show_spread_enabled(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
if (data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD)
return sprintf(buf, "1\n");
return sprintf(buf, "0\n");
}
/* bit to cpu khz map */
static const int fs_speeds[] = {
266666,
133333,
200000,
166666,
333333,
100000,
400000,
0,
};
/* clock divisor map */
static const int divisors[] = {2, 3, 5, 15, 4, 6, 10, 30, 8, 12, 20, 60, 16,
24, 40, 120};
/* Calculate CPU frequency from the M/N registers. */
static int calculate_cpu_freq(struct ics932s401_data *data)
{
int m, n, freq;
m = data->regs[ICS932S401_REG_CPU_M_CTRL] & ICS932S401_M_MASK;
n = data->regs[ICS932S401_REG_CPU_N_CTRL];
/* Pull in bits 8 & 9 from the M register */
n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x80) << 1;
n |= ((int)data->regs[ICS932S401_REG_CPU_M_CTRL] & 0x40) << 3;
freq = BASE_CLOCK * (n + 8) / (m + 2);
freq /= divisors[data->regs[ICS932S401_REG_CPU_DIVISOR] >>
ICS932S401_CPU_DIVISOR_SHIFT];
return freq;
}
static ssize_t show_cpu_clock(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
return sprintf(buf, "%d\n", calculate_cpu_freq(data));
}
static ssize_t show_cpu_clock_sel(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
int freq;
if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
freq = calculate_cpu_freq(data);
else {
/* Freq is neatly wrapped up for us */
int fid = data->regs[ICS932S401_REG_CFG7] & ICS932S401_FS_MASK;
freq = fs_speeds[fid];
if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT) {
switch (freq) {
case 166666:
freq = 160000;
break;
case 333333:
freq = 320000;
break;
}
}
}
return sprintf(buf, "%d\n", freq);
}
/* Calculate SRC frequency from the M/N registers. */
static int calculate_src_freq(struct ics932s401_data *data)
{
int m, n, freq;
m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
n = data->regs[ICS932S401_REG_SRC_N_CTRL];
/* Pull in bits 8 & 9 from the M register */
n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
freq = BASE_CLOCK * (n + 8) / (m + 2);
freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] &
ICS932S401_SRC_DIVISOR_MASK];
return freq;
}
static ssize_t show_src_clock(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
return sprintf(buf, "%d\n", calculate_src_freq(data));
}
static ssize_t show_src_clock_sel(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
int freq;
if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
freq = calculate_src_freq(data);
else
/* Freq is neatly wrapped up for us */
if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_CPU_ALT &&
data->regs[ICS932S401_REG_CTRL] & ICS932S401_SRC_ALT)
freq = 96000;
else
freq = 100000;
return sprintf(buf, "%d\n", freq);
}
/* Calculate PCI frequency from the SRC M/N registers. */
static int calculate_pci_freq(struct ics932s401_data *data)
{
int m, n, freq;
m = data->regs[ICS932S401_REG_SRC_M_CTRL] & ICS932S401_M_MASK;
n = data->regs[ICS932S401_REG_SRC_N_CTRL];
/* Pull in bits 8 & 9 from the M register */
n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x80) << 1;
n |= ((int)data->regs[ICS932S401_REG_SRC_M_CTRL] & 0x40) << 3;
freq = BASE_CLOCK * (n + 8) / (m + 2);
freq /= divisors[data->regs[ICS932S401_REG_PCISRC_DIVISOR] >>
ICS932S401_PCI_DIVISOR_SHIFT];
return freq;
}
static ssize_t show_pci_clock(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
return sprintf(buf, "%d\n", calculate_pci_freq(data));
}
static ssize_t show_pci_clock_sel(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
int freq;
if (data->regs[ICS932S401_REG_CTRL] & ICS932S401_MN_ENABLED)
freq = calculate_pci_freq(data);
else
freq = 33333;
return sprintf(buf, "%d\n", freq);
}
static ssize_t show_value(struct device *dev,
struct device_attribute *devattr,
char *buf);
static ssize_t show_spread(struct device *dev,
struct device_attribute *devattr,
char *buf);
static DEVICE_ATTR(spread_enabled, S_IRUGO, show_spread_enabled, NULL);
static DEVICE_ATTR(cpu_clock_selection, S_IRUGO, show_cpu_clock_sel, NULL);
static DEVICE_ATTR(cpu_clock, S_IRUGO, show_cpu_clock, NULL);
static DEVICE_ATTR(src_clock_selection, S_IRUGO, show_src_clock_sel, NULL);
static DEVICE_ATTR(src_clock, S_IRUGO, show_src_clock, NULL);
static DEVICE_ATTR(pci_clock_selection, S_IRUGO, show_pci_clock_sel, NULL);
static DEVICE_ATTR(pci_clock, S_IRUGO, show_pci_clock, NULL);
static DEVICE_ATTR(usb_clock, S_IRUGO, show_value, NULL);
static DEVICE_ATTR(ref_clock, S_IRUGO, show_value, NULL);
static DEVICE_ATTR(cpu_spread, S_IRUGO, show_spread, NULL);
static DEVICE_ATTR(src_spread, S_IRUGO, show_spread, NULL);
static struct attribute *ics932s401_attr[] =
{
&dev_attr_spread_enabled.attr,
&dev_attr_cpu_clock_selection.attr,
&dev_attr_cpu_clock.attr,
&dev_attr_src_clock_selection.attr,
&dev_attr_src_clock.attr,
&dev_attr_pci_clock_selection.attr,
&dev_attr_pci_clock.attr,
&dev_attr_usb_clock.attr,
&dev_attr_ref_clock.attr,
&dev_attr_cpu_spread.attr,
&dev_attr_src_spread.attr,
NULL
};
static ssize_t show_value(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
int x;
if (devattr == &dev_attr_usb_clock)
x = 48000;
else if (devattr == &dev_attr_ref_clock)
x = BASE_CLOCK;
else
BUG();
return sprintf(buf, "%d\n", x);
}
static ssize_t show_spread(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
struct ics932s401_data *data = ics932s401_update_device(dev);
int reg;
unsigned long val;
if (!(data->regs[ICS932S401_REG_CFG2] & ICS932S401_CFG1_SPREAD))
return sprintf(buf, "0%%\n");
if (devattr == &dev_attr_src_spread)
reg = ICS932S401_REG_SRC_SPREAD1;
else if (devattr == &dev_attr_cpu_spread)
reg = ICS932S401_REG_CPU_SPREAD1;
else
BUG();
val = data->regs[reg] | (data->regs[reg + 1] << 8);
val &= ICS932S401_SPREAD_MASK;
/* Scale 0..2^14 to -0.5. */
val = 500000 * val / 16384;
return sprintf(buf, "-0.%lu%%\n", val);
}
/* Return 0 if detection is successful, -ENODEV otherwise */
static int ics932s401_detect(struct i2c_client *client, int kind,
struct i2c_board_info *info)
{
struct i2c_adapter *adapter = client->adapter;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
if (kind <= 0) {
int vendor, device, revision;
vendor = i2c_smbus_read_word_data(client,
ICS932S401_REG_VENDOR_REV);
vendor >>= 8;
revision = vendor >> ICS932S401_REV_SHIFT;
vendor &= ICS932S401_VENDOR_MASK;
if (vendor != ICS932S401_VENDOR)
return -ENODEV;
device = i2c_smbus_read_word_data(client,
ICS932S401_REG_DEVICE);
device >>= 8;
if (device != ICS932S401_DEVICE)
return -ENODEV;
if (revision != ICS932S401_REV)
dev_info(&adapter->dev, "Unknown revision %d\n",
revision);
} else
dev_dbg(&adapter->dev, "detection forced\n");
strlcpy(info->type, "ics932s401", I2C_NAME_SIZE);
return 0;
}
static int ics932s401_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct ics932s401_data *data;
int err;
data = kzalloc(sizeof(struct ics932s401_data), GFP_KERNEL);
if (!data) {
err = -ENOMEM;
goto exit;
}
i2c_set_clientdata(client, data);
mutex_init(&data->lock);
dev_info(&client->dev, "%s chip found\n", client->name);
/* Register sysfs hooks */
data->attrs.attrs = ics932s401_attr;
err = sysfs_create_group(&client->dev.kobj, &data->attrs);
if (err)
goto exit_free;
return 0;
exit_free:
kfree(data);
exit:
return err;
}
static int ics932s401_remove(struct i2c_client *client)
{
struct ics932s401_data *data = i2c_get_clientdata(client);
sysfs_remove_group(&client->dev.kobj, &data->attrs);
kfree(data);
return 0;
}
static int __init ics932s401_init(void)
{
return i2c_add_driver(&ics932s401_driver);
}
static void __exit ics932s401_exit(void)
{
i2c_del_driver(&ics932s401_driver);
}
MODULE_AUTHOR("Darrick J. Wong <djwong@us.ibm.com>");
MODULE_DESCRIPTION("ICS932S401 driver");
MODULE_LICENSE("GPL");
module_init(ics932s401_init);
module_exit(ics932s401_exit);
/* IBM IntelliStation Z30 */
MODULE_ALIAS("dmi:bvnIBM:*:rn9228:*");
MODULE_ALIAS("dmi:bvnIBM:*:rn9232:*");
/* IBM x3650/x3550 */
MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3650*");
MODULE_ALIAS("dmi:bvnIBM:*:pnIBMSystemx3550*");
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment