[PATCH] ics932s401: New driver
From: Darrick J. Wong
Date: Fri Nov 07 2008 - 14:11:31 EST
The ics932s401 is a clock generator chip. This driver allows users to read
the current clock outputs.
Signed-off-by: Darrick J. Wong <djwong@xxxxxxxxxx>
---
Documentation/ics932s401 | 31 +++
drivers/misc/Kconfig | 10 +
drivers/misc/Makefile | 1
drivers/misc/ics932s401.c | 515 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 557 insertions(+), 0 deletions(-)
diff --git a/Documentation/ics932s401 b/Documentation/ics932s401
new file mode 100644
index 0000000..07a739f
--- /dev/null
+++ b/Documentation/ics932s401
@@ -0,0 +1,31 @@
+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!
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 9494400..6917d61 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -227,6 +227,16 @@ config HP_WMI
To compile this driver as a module, choose M here: the module will
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
tristate "MSI Laptop Extras"
depends on X86
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 909e246..bb14633 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_ATMEL_PWM) += atmel_pwm.o
obj-$(CONFIG_ATMEL_SSC) += atmel-ssc.o
obj-$(CONFIG_ATMEL_TCLIB) += atmel_tclib.o
obj-$(CONFIG_HP_WMI) += hp-wmi.o
+obj-$(CONFIG_ICS932S401) += ics932s401.o
obj-$(CONFIG_TC1100_WMI) += tc1100-wmi.o
obj-$(CONFIG_LKDTM) += lkdtm.o
obj-$(CONFIG_TIFM_CORE) += tifm_core.o
diff --git a/drivers/misc/ics932s401.c b/drivers/misc/ics932s401.c
new file mode 100644
index 0000000..6e43ab4
--- /dev/null
+++ b/drivers/misc/ics932s401.c
@@ -0,0 +1,515 @@
+/*
+ * A driver for the Integrated Circuits ICS932S401
+ * Copyright (C) 2008 IBM
+ *
+ * Author: Darrick J. Wong <djwong@xxxxxxxxxx>
+ *
+ * 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@xxxxxxxxxx>");
+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*");
--
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