From: "Edward A. James" <[email protected]>
This series enables debugfs entries in the IBM common form factor power supply
driver. In order to avoid multiple debugfs directories for the same driver, the
first patch in the series allows a pmbus client driver to query pmbus core for
it's debugfs directory.
The second patch in the series adds debugfs files for a number of attributes of
the power supply, including FRU (field replaceable unit) number, firmware
version, part number, serial number, and CCIN. There is also an entry for the
psu "input history" in binary format. This data represents previous 10 minutes
of power supply data.
Changes since v2:
- CCIN is big-endian and has to be swapped.
Changes since v1:
- Check for debugfs directory before allocating memory.
- Add cffps1 sub-directory for the debugfs entries.
- Always set last_update to jiffies - HZ.
- Add EXPORT_SYMBOL_GPL for pmbus_get_debugfs_dir().
Edward A. James (2):
hwmon (pmbus): Export pmbus device debugfs directory entry
hwmon (pmbus): cffps: Add debugfs entries
drivers/hwmon/pmbus/ibm-cffps.c | 202 ++++++++++++++++++++++++++++++++++++++-
drivers/hwmon/pmbus/pmbus.h | 2 +
drivers/hwmon/pmbus/pmbus_core.c | 8 ++
3 files changed, 211 insertions(+), 1 deletion(-)
--
1.8.3.1
From: "Edward A. James" <[email protected]>
Add debugfs entries for additional power supply data, including part
number, serial number, FRU number, firmware revision, ccin, and the
input history of the power supply. The input history is 10 minutes of
input power data in the form of twenty 30-second packets. Each packet
contains average and maximum power for that 30 second period.
Signed-off-by: Edward A. James <[email protected]>
---
drivers/hwmon/pmbus/ibm-cffps.c | 202 +++++++++++++++++++++++++++++++++++++++-
1 file changed, 201 insertions(+), 1 deletion(-)
diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
index cb56da6..5376f04 100644
--- a/drivers/hwmon/pmbus/ibm-cffps.c
+++ b/drivers/hwmon/pmbus/ibm-cffps.c
@@ -8,12 +8,26 @@
*/
#include <linux/bitops.h>
+#include <linux/debugfs.h>
#include <linux/device.h>
+#include <linux/fs.h>
#include <linux/i2c.h>
+#include <linux/jiffies.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include "pmbus.h"
+#define CFFPS_FRU_CMD 0x9A
+#define CFFPS_PN_CMD 0x9B
+#define CFFPS_SN_CMD 0x9E
+#define CFFPS_CCIN_CMD 0xBD
+#define CFFPS_FW_CMD_START 0xFA
+#define CFFPS_FW_NUM_BYTES 4
+
+#define CFFPS_INPUT_HISTORY_CMD 0xD6
+#define CFFPS_INPUT_HISTORY_SIZE 100
+
/* STATUS_MFR_SPECIFIC bits */
#define CFFPS_MFR_FAN_FAULT BIT(0)
#define CFFPS_MFR_THERMAL_FAULT BIT(1)
@@ -24,6 +38,144 @@
#define CFFPS_MFR_VAUX_FAULT BIT(6)
#define CFFPS_MFR_CURRENT_SHARE_WARNING BIT(7)
+enum {
+ CFFPS_DEBUGFS_INPUT_HISTORY = 0,
+ CFFPS_DEBUGFS_FRU,
+ CFFPS_DEBUGFS_PN,
+ CFFPS_DEBUGFS_SN,
+ CFFPS_DEBUGFS_CCIN,
+ CFFPS_DEBUGFS_FW,
+ CFFPS_DEBUGFS_NUM_ENTRIES
+};
+
+struct ibm_cffps_input_history {
+ struct mutex update_lock;
+ unsigned long last_update;
+
+ u8 byte_count;
+ u8 data[CFFPS_INPUT_HISTORY_SIZE];
+};
+
+struct ibm_cffps {
+ struct i2c_client *client;
+
+ struct ibm_cffps_input_history input_history;
+
+ int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];
+};
+
+#define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
+
+static ssize_t ibm_cffps_read_input_history(struct ibm_cffps *psu,
+ char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ int rc;
+ u8 msgbuf0[1] = { CFFPS_INPUT_HISTORY_CMD };
+ u8 msgbuf1[CFFPS_INPUT_HISTORY_SIZE + 1] = { 0 };
+ struct i2c_msg msg[2] = {
+ {
+ .addr = psu->client->addr,
+ .flags = psu->client->flags,
+ .len = 1,
+ .buf = msgbuf0,
+ }, {
+ .addr = psu->client->addr,
+ .flags = psu->client->flags | I2C_M_RD,
+ .len = CFFPS_INPUT_HISTORY_SIZE + 1,
+ .buf = msgbuf1,
+ },
+ };
+
+ if (!*ppos) {
+ mutex_lock(&psu->input_history.update_lock);
+ if (time_after(jiffies, psu->input_history.last_update + HZ)) {
+ /*
+ * Use a raw i2c transfer, since we need more bytes
+ * than Linux I2C supports through smbus xfr (only 32).
+ */
+ rc = i2c_transfer(psu->client->adapter, msg, 2);
+ if (rc < 0) {
+ mutex_unlock(&psu->input_history.update_lock);
+ return rc;
+ }
+
+ psu->input_history.byte_count = msgbuf1[0];
+ memcpy(psu->input_history.data, &msgbuf1[1],
+ CFFPS_INPUT_HISTORY_SIZE);
+ psu->input_history.last_update = jiffies;
+ }
+
+ mutex_unlock(&psu->input_history.update_lock);
+ }
+
+ return simple_read_from_buffer(buf, count, ppos,
+ psu->input_history.data,
+ psu->input_history.byte_count);
+}
+
+static ssize_t ibm_cffps_debugfs_op(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ u8 cmd;
+ int i, rc;
+ int *idxp = file->private_data;
+ int idx = *idxp;
+ struct ibm_cffps *psu = to_psu(idxp, idx);
+ char data[I2C_SMBUS_BLOCK_MAX] = { 0 };
+
+ switch (idx) {
+ case CFFPS_DEBUGFS_INPUT_HISTORY:
+ return ibm_cffps_read_input_history(psu, buf, count, ppos);
+ case CFFPS_DEBUGFS_FRU:
+ cmd = CFFPS_FRU_CMD;
+ break;
+ case CFFPS_DEBUGFS_PN:
+ cmd = CFFPS_PN_CMD;
+ break;
+ case CFFPS_DEBUGFS_SN:
+ cmd = CFFPS_SN_CMD;
+ break;
+ case CFFPS_DEBUGFS_CCIN:
+ rc = i2c_smbus_read_word_data(psu->client, CFFPS_CCIN_CMD);
+ if (rc < 0)
+ return rc;
+
+ rc = snprintf(data, 5, "%04X", be16_to_cpu(rc));
+ goto done;
+ case CFFPS_DEBUGFS_FW:
+ for (i = 0; i < CFFPS_FW_NUM_BYTES; ++i) {
+ rc = i2c_smbus_read_byte_data(psu->client,
+ CFFPS_FW_CMD_START + i);
+ if (rc < 0)
+ return rc;
+
+ snprintf(&data[i * 2], 3, "%02X", rc);
+ }
+
+ rc = i * 2;
+ goto done;
+ default:
+ return -EINVAL;
+ }
+
+ rc = i2c_smbus_read_block_data(psu->client, cmd, data);
+ if (rc < 0)
+ return rc;
+
+done:
+ data[rc] = '\n';
+ rc += 2;
+
+ return simple_read_from_buffer(buf, count, ppos, data, rc);
+}
+
+static const struct file_operations ibm_cffps_fops = {
+ .llseek = noop_llseek,
+ .read = ibm_cffps_debugfs_op,
+ .open = simple_open,
+};
+
static int ibm_cffps_read_byte_data(struct i2c_client *client, int page,
int reg)
{
@@ -119,7 +271,55 @@ static int ibm_cffps_read_word_data(struct i2c_client *client, int page,
static int ibm_cffps_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- return pmbus_do_probe(client, id, &ibm_cffps_info);
+ int i, rc;
+ struct dentry *debugfs;
+ struct dentry *ibm_cffps_dir;
+ struct ibm_cffps *psu;
+
+ rc = pmbus_do_probe(client, id, &ibm_cffps_info);
+ if (rc)
+ return rc;
+
+ /* Don't fail the probe if we can't create debugfs */
+ debugfs = pmbus_get_debugfs_dir(client);
+ if (!debugfs)
+ return 0;
+
+ ibm_cffps_dir = debugfs_create_dir(client->name, debugfs);
+ if (!ibm_cffps_dir)
+ return 0;
+
+ psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
+ if (!psu)
+ return 0;
+
+ psu->client = client;
+ mutex_init(&psu->input_history.update_lock);
+ psu->input_history.last_update = jiffies - HZ;
+
+ for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
+ psu->debugfs_entries[i] = i;
+
+ debugfs_create_file("input_history", 0444, ibm_cffps_dir,
+ &psu->debugfs_entries[CFFPS_DEBUGFS_INPUT_HISTORY],
+ &ibm_cffps_fops);
+ debugfs_create_file("fru", 0444, ibm_cffps_dir,
+ &psu->debugfs_entries[CFFPS_DEBUGFS_FRU],
+ &ibm_cffps_fops);
+ debugfs_create_file("part_number", 0444, ibm_cffps_dir,
+ &psu->debugfs_entries[CFFPS_DEBUGFS_PN],
+ &ibm_cffps_fops);
+ debugfs_create_file("serial_number", 0444, ibm_cffps_dir,
+ &psu->debugfs_entries[CFFPS_DEBUGFS_SN],
+ &ibm_cffps_fops);
+ debugfs_create_file("ccin", 0444, ibm_cffps_dir,
+ &psu->debugfs_entries[CFFPS_DEBUGFS_CCIN],
+ &ibm_cffps_fops);
+ debugfs_create_file("fw_version", 0444, ibm_cffps_dir,
+ &psu->debugfs_entries[CFFPS_DEBUGFS_FW],
+ &ibm_cffps_fops);
+
+ return 0;
}
static const struct i2c_device_id ibm_cffps_id[] = {
--
1.8.3.1
From: "Edward A. James" <[email protected]>
Pmbus client drivers, if they want to use debugfs, should use the same
root directory as the pmbus debugfs entries are using. Therefore, export
the device dentry for the pmbus client.
Signed-off-by: Edward A. James <[email protected]>
---
drivers/hwmon/pmbus/pmbus.h | 2 ++
drivers/hwmon/pmbus/pmbus_core.c | 8 ++++++++
2 files changed, 10 insertions(+)
diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
index d39d506..1d24397 100644
--- a/drivers/hwmon/pmbus/pmbus.h
+++ b/drivers/hwmon/pmbus/pmbus.h
@@ -461,4 +461,6 @@ int pmbus_get_fan_rate_cached(struct i2c_client *client, int page, int id,
enum pmbus_fan_mode mode);
int pmbus_update_fan(struct i2c_client *client, int page, int id,
u8 config, u8 mask, u16 command);
+struct dentry *pmbus_get_debugfs_dir(struct i2c_client *client);
+
#endif /* PMBUS_H */
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 99ab39f..f7c47d7 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -2381,6 +2381,14 @@ int pmbus_do_remove(struct i2c_client *client)
}
EXPORT_SYMBOL_GPL(pmbus_do_remove);
+struct dentry *pmbus_get_debugfs_dir(struct i2c_client *client)
+{
+ struct pmbus_data *data = i2c_get_clientdata(client);
+
+ return data->debugfs;
+}
+EXPORT_SYMBOL_GPL(pmbus_get_debugfs_dir);
+
static int __init pmbus_core_init(void)
{
pmbus_debugfs_dir = debugfs_create_dir("pmbus", NULL);
--
1.8.3.1
On Mon, Dec 11, 2017 at 03:32:49PM -0600, [email protected] wrote:
> From: "Edward A. James" <[email protected]>
>
> Pmbus client drivers, if they want to use debugfs, should use the same
> root directory as the pmbus debugfs entries are using. Therefore, export
> the device dentry for the pmbus client.
>
> Signed-off-by: Edward A. James <[email protected]>
Applied to hwmon-next.
Thanks,
Guenter
> ---
> drivers/hwmon/pmbus/pmbus.h | 2 ++
> drivers/hwmon/pmbus/pmbus_core.c | 8 ++++++++
> 2 files changed, 10 insertions(+)
>
> diff --git a/drivers/hwmon/pmbus/pmbus.h b/drivers/hwmon/pmbus/pmbus.h
> index d39d506..1d24397 100644
> --- a/drivers/hwmon/pmbus/pmbus.h
> +++ b/drivers/hwmon/pmbus/pmbus.h
> @@ -461,4 +461,6 @@ int pmbus_get_fan_rate_cached(struct i2c_client *client, int page, int id,
> enum pmbus_fan_mode mode);
> int pmbus_update_fan(struct i2c_client *client, int page, int id,
> u8 config, u8 mask, u16 command);
> +struct dentry *pmbus_get_debugfs_dir(struct i2c_client *client);
> +
> #endif /* PMBUS_H */
> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
> index 99ab39f..f7c47d7 100644
> --- a/drivers/hwmon/pmbus/pmbus_core.c
> +++ b/drivers/hwmon/pmbus/pmbus_core.c
> @@ -2381,6 +2381,14 @@ int pmbus_do_remove(struct i2c_client *client)
> }
> EXPORT_SYMBOL_GPL(pmbus_do_remove);
>
> +struct dentry *pmbus_get_debugfs_dir(struct i2c_client *client)
> +{
> + struct pmbus_data *data = i2c_get_clientdata(client);
> +
> + return data->debugfs;
> +}
> +EXPORT_SYMBOL_GPL(pmbus_get_debugfs_dir);
> +
> static int __init pmbus_core_init(void)
> {
> pmbus_debugfs_dir = debugfs_create_dir("pmbus", NULL);
On Mon, Dec 11, 2017 at 03:32:50PM -0600, [email protected] wrote:
> From: "Edward A. James" <[email protected]>
>
> Add debugfs entries for additional power supply data, including part
> number, serial number, FRU number, firmware revision, ccin, and the
> input history of the power supply. The input history is 10 minutes of
> input power data in the form of twenty 30-second packets. Each packet
> contains average and maximum power for that 30 second period.
>
> Signed-off-by: Edward A. James <[email protected]>
Applied to hwmon-next.
Thanks,
Guenter
> ---
> drivers/hwmon/pmbus/ibm-cffps.c | 202 +++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 201 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c
> index cb56da6..5376f04 100644
> --- a/drivers/hwmon/pmbus/ibm-cffps.c
> +++ b/drivers/hwmon/pmbus/ibm-cffps.c
> @@ -8,12 +8,26 @@
> */
>
> #include <linux/bitops.h>
> +#include <linux/debugfs.h>
> #include <linux/device.h>
> +#include <linux/fs.h>
> #include <linux/i2c.h>
> +#include <linux/jiffies.h>
> #include <linux/module.h>
> +#include <linux/mutex.h>
>
> #include "pmbus.h"
>
> +#define CFFPS_FRU_CMD 0x9A
> +#define CFFPS_PN_CMD 0x9B
> +#define CFFPS_SN_CMD 0x9E
> +#define CFFPS_CCIN_CMD 0xBD
> +#define CFFPS_FW_CMD_START 0xFA
> +#define CFFPS_FW_NUM_BYTES 4
> +
> +#define CFFPS_INPUT_HISTORY_CMD 0xD6
> +#define CFFPS_INPUT_HISTORY_SIZE 100
> +
> /* STATUS_MFR_SPECIFIC bits */
> #define CFFPS_MFR_FAN_FAULT BIT(0)
> #define CFFPS_MFR_THERMAL_FAULT BIT(1)
> @@ -24,6 +38,144 @@
> #define CFFPS_MFR_VAUX_FAULT BIT(6)
> #define CFFPS_MFR_CURRENT_SHARE_WARNING BIT(7)
>
> +enum {
> + CFFPS_DEBUGFS_INPUT_HISTORY = 0,
> + CFFPS_DEBUGFS_FRU,
> + CFFPS_DEBUGFS_PN,
> + CFFPS_DEBUGFS_SN,
> + CFFPS_DEBUGFS_CCIN,
> + CFFPS_DEBUGFS_FW,
> + CFFPS_DEBUGFS_NUM_ENTRIES
> +};
> +
> +struct ibm_cffps_input_history {
> + struct mutex update_lock;
> + unsigned long last_update;
> +
> + u8 byte_count;
> + u8 data[CFFPS_INPUT_HISTORY_SIZE];
> +};
> +
> +struct ibm_cffps {
> + struct i2c_client *client;
> +
> + struct ibm_cffps_input_history input_history;
> +
> + int debugfs_entries[CFFPS_DEBUGFS_NUM_ENTRIES];
> +};
> +
> +#define to_psu(x, y) container_of((x), struct ibm_cffps, debugfs_entries[(y)])
> +
> +static ssize_t ibm_cffps_read_input_history(struct ibm_cffps *psu,
> + char __user *buf, size_t count,
> + loff_t *ppos)
> +{
> + int rc;
> + u8 msgbuf0[1] = { CFFPS_INPUT_HISTORY_CMD };
> + u8 msgbuf1[CFFPS_INPUT_HISTORY_SIZE + 1] = { 0 };
> + struct i2c_msg msg[2] = {
> + {
> + .addr = psu->client->addr,
> + .flags = psu->client->flags,
> + .len = 1,
> + .buf = msgbuf0,
> + }, {
> + .addr = psu->client->addr,
> + .flags = psu->client->flags | I2C_M_RD,
> + .len = CFFPS_INPUT_HISTORY_SIZE + 1,
> + .buf = msgbuf1,
> + },
> + };
> +
> + if (!*ppos) {
> + mutex_lock(&psu->input_history.update_lock);
> + if (time_after(jiffies, psu->input_history.last_update + HZ)) {
> + /*
> + * Use a raw i2c transfer, since we need more bytes
> + * than Linux I2C supports through smbus xfr (only 32).
> + */
> + rc = i2c_transfer(psu->client->adapter, msg, 2);
> + if (rc < 0) {
> + mutex_unlock(&psu->input_history.update_lock);
> + return rc;
> + }
> +
> + psu->input_history.byte_count = msgbuf1[0];
> + memcpy(psu->input_history.data, &msgbuf1[1],
> + CFFPS_INPUT_HISTORY_SIZE);
> + psu->input_history.last_update = jiffies;
> + }
> +
> + mutex_unlock(&psu->input_history.update_lock);
> + }
> +
> + return simple_read_from_buffer(buf, count, ppos,
> + psu->input_history.data,
> + psu->input_history.byte_count);
> +}
> +
> +static ssize_t ibm_cffps_debugfs_op(struct file *file, char __user *buf,
> + size_t count, loff_t *ppos)
> +{
> + u8 cmd;
> + int i, rc;
> + int *idxp = file->private_data;
> + int idx = *idxp;
> + struct ibm_cffps *psu = to_psu(idxp, idx);
> + char data[I2C_SMBUS_BLOCK_MAX] = { 0 };
> +
> + switch (idx) {
> + case CFFPS_DEBUGFS_INPUT_HISTORY:
> + return ibm_cffps_read_input_history(psu, buf, count, ppos);
> + case CFFPS_DEBUGFS_FRU:
> + cmd = CFFPS_FRU_CMD;
> + break;
> + case CFFPS_DEBUGFS_PN:
> + cmd = CFFPS_PN_CMD;
> + break;
> + case CFFPS_DEBUGFS_SN:
> + cmd = CFFPS_SN_CMD;
> + break;
> + case CFFPS_DEBUGFS_CCIN:
> + rc = i2c_smbus_read_word_data(psu->client, CFFPS_CCIN_CMD);
> + if (rc < 0)
> + return rc;
> +
> + rc = snprintf(data, 5, "%04X", be16_to_cpu(rc));
> + goto done;
> + case CFFPS_DEBUGFS_FW:
> + for (i = 0; i < CFFPS_FW_NUM_BYTES; ++i) {
> + rc = i2c_smbus_read_byte_data(psu->client,
> + CFFPS_FW_CMD_START + i);
> + if (rc < 0)
> + return rc;
> +
> + snprintf(&data[i * 2], 3, "%02X", rc);
> + }
> +
> + rc = i * 2;
> + goto done;
> + default:
> + return -EINVAL;
> + }
> +
> + rc = i2c_smbus_read_block_data(psu->client, cmd, data);
> + if (rc < 0)
> + return rc;
> +
> +done:
> + data[rc] = '\n';
> + rc += 2;
> +
> + return simple_read_from_buffer(buf, count, ppos, data, rc);
> +}
> +
> +static const struct file_operations ibm_cffps_fops = {
> + .llseek = noop_llseek,
> + .read = ibm_cffps_debugfs_op,
> + .open = simple_open,
> +};
> +
> static int ibm_cffps_read_byte_data(struct i2c_client *client, int page,
> int reg)
> {
> @@ -119,7 +271,55 @@ static int ibm_cffps_read_word_data(struct i2c_client *client, int page,
> static int ibm_cffps_probe(struct i2c_client *client,
> const struct i2c_device_id *id)
> {
> - return pmbus_do_probe(client, id, &ibm_cffps_info);
> + int i, rc;
> + struct dentry *debugfs;
> + struct dentry *ibm_cffps_dir;
> + struct ibm_cffps *psu;
> +
> + rc = pmbus_do_probe(client, id, &ibm_cffps_info);
> + if (rc)
> + return rc;
> +
> + /* Don't fail the probe if we can't create debugfs */
> + debugfs = pmbus_get_debugfs_dir(client);
> + if (!debugfs)
> + return 0;
> +
> + ibm_cffps_dir = debugfs_create_dir(client->name, debugfs);
> + if (!ibm_cffps_dir)
> + return 0;
> +
> + psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
> + if (!psu)
> + return 0;
> +
> + psu->client = client;
> + mutex_init(&psu->input_history.update_lock);
> + psu->input_history.last_update = jiffies - HZ;
> +
> + for (i = 0; i < CFFPS_DEBUGFS_NUM_ENTRIES; ++i)
> + psu->debugfs_entries[i] = i;
> +
> + debugfs_create_file("input_history", 0444, ibm_cffps_dir,
> + &psu->debugfs_entries[CFFPS_DEBUGFS_INPUT_HISTORY],
> + &ibm_cffps_fops);
> + debugfs_create_file("fru", 0444, ibm_cffps_dir,
> + &psu->debugfs_entries[CFFPS_DEBUGFS_FRU],
> + &ibm_cffps_fops);
> + debugfs_create_file("part_number", 0444, ibm_cffps_dir,
> + &psu->debugfs_entries[CFFPS_DEBUGFS_PN],
> + &ibm_cffps_fops);
> + debugfs_create_file("serial_number", 0444, ibm_cffps_dir,
> + &psu->debugfs_entries[CFFPS_DEBUGFS_SN],
> + &ibm_cffps_fops);
> + debugfs_create_file("ccin", 0444, ibm_cffps_dir,
> + &psu->debugfs_entries[CFFPS_DEBUGFS_CCIN],
> + &ibm_cffps_fops);
> + debugfs_create_file("fw_version", 0444, ibm_cffps_dir,
> + &psu->debugfs_entries[CFFPS_DEBUGFS_FW],
> + &ibm_cffps_fops);
> +
> + return 0;
> }
>
> static const struct i2c_device_id ibm_cffps_id[] = {