* [RFC Patch v4 0/1] i2c statistics as sysfs attributes
@ 2022-04-01 0:21 Sui Chen
2022-04-01 0:22 ` [RFC Patch v4 1/1] i2c debug counters " Sui Chen
0 siblings, 1 reply; 5+ messages in thread
From: Sui Chen @ 2022-04-01 0:21 UTC (permalink / raw)
To: linux-i2c, openbmc, joel, andrew, tali.perry1, benjaminfair, krellan
Cc: Sui Chen
This change renames the I2C debug counters as suggested, and moves their
processing into the i2c core:
- bus_errors
- transfers
- nacks
- recovery_successes
- recovery_failures
- timeouts
Did some brief tests with a few test programs that saves/replays I2C
trace by reading hwmon sensors. The test program and hardware run in
QEMU. The test programs are located at
https://gerrit.openbmc-project.xyz/c/openbmc/openbmc-tools/+/52527
(A normal read)
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
264
root@gsj:/tmp# ./i2c_bmk_bmc 0
idx=0
Processing 1 inputs
/sys/class/hwmon/hwmon0/temp1_input
(../../devices/platform/ahb/ahb:apb/f0081000.i2c/i2c-1/1-005c/hwmon/hwmon0):
0
[FindTraceEntries] t0=391.000000 t1=393.000000
Found 4 interesting I2C trace entries:
i2c_write: i2c-1 #0 a=05c f=0000 l=1 [00]
i2c_read: i2c-1 #1 a=05c f=0001 l=2
i2c_reply: i2c-1 #1 a=05c f=0001 l=2 [00-00]
i2c_result: i2c-1 n=2 ret=2
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
265
(Read from an inexistent address, NACK)
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
6
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
265
root@gsj:/tmp# cat i2c_trace.txt
i2c_write: i2c-1 #0 a=0ff f=0000 l=1 [00]
i2c_read: i2c-1 #1 a=0ff f=0001 l=2
root@gsj:/tmp# ./i2c_replay_bmc i2c_trace.txt
(program runs and finishes with 6 errors)
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
12
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
265
The program makes 2 attempts, performing 3 I2C operations at each
attempt, which translates to the 6 nack events.
We will do more testing.
Sui Chen (1):
i2c debug counters as sysfs attributes
drivers/i2c/i2c-core-base.c | 32 ++++++++++++-
drivers/i2c/i2c-dev.c | 94 +++++++++++++++++++++++++++++++++++++
include/linux/i2c.h | 26 ++++++++++
3 files changed, 151 insertions(+), 1 deletion(-)
--
2.35.1.1094.g7c7d902a7c-goog
^ permalink raw reply [flat|nested] 5+ messages in thread
* [RFC Patch v4 1/1] i2c debug counters as sysfs attributes
2022-04-01 0:21 [RFC Patch v4 0/1] i2c statistics as sysfs attributes Sui Chen
@ 2022-04-01 0:22 ` Sui Chen
2022-04-03 12:12 ` Avi Fishman
0 siblings, 1 reply; 5+ messages in thread
From: Sui Chen @ 2022-04-01 0:22 UTC (permalink / raw)
To: linux-i2c, openbmc, joel, andrew, tali.perry1, benjaminfair, krellan
Cc: Sui Chen
This change renames the I2C debug counters as suggested, and moves their
processing into the i2c core:
- bus_errors
- transfers
- nacks
- recovery_successes
- recovery_failures
- timeouts
The function i2c_adapter_create_stats_folder creates a stats directory
in the device's sysfs directory to hold the above debug counters.
Did some brief tests with a few test programs that saves/replays I2C
trace by reading hwmon sensors. The test program and hardware run in
QEMU. The test programs are located at
https://gerrit.openbmc-project.xyz/c/openbmc/openbmc-tools/+/52527
(A normal read)
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
264
root@gsj:/tmp# ./i2c_bmk_bmc 0
idx=0
Processing 1 inputs
/sys/class/hwmon/hwmon0/temp1_input
(../../devices/platform/ahb/ahb:apb/f0081000.i2c/i2c-1/1-005c/hwmon/hwmon0):
0
[FindTraceEntries] t0=391.000000 t1=393.000000
Found 4 interesting I2C trace entries:
i2c_write: i2c-1 #0 a=05c f=0000 l=1 [00]
i2c_read: i2c-1 #1 a=05c f=0001 l=2
i2c_reply: i2c-1 #1 a=05c f=0001 l=2 [00-00]
i2c_result: i2c-1 n=2 ret=2
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
265
(Read from an inexistent address, NACK)
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
6
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
265
root@gsj:/tmp# cat i2c_trace.txt
i2c_write: i2c-1 #0 a=0ff f=0000 l=1 [00]
i2c_read: i2c-1 #1 a=0ff f=0001 l=2
root@gsj:/tmp# ./i2c_replay_bmc i2c_trace.txt
(program runs and completes)
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
12
root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
265
The program makes 2 attempts, performing 3 I2C operations at each
attempt, which translates to the 6 nack events.
Signed-off-by: Sui Chen <suichen@google.com>
---
drivers/i2c/i2c-core-base.c | 32 ++++++++++++-
drivers/i2c/i2c-dev.c | 94 +++++++++++++++++++++++++++++++++++++
include/linux/i2c.h | 26 ++++++++++
3 files changed, 151 insertions(+), 1 deletion(-)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 84f12bf90644..53688b1d855a 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -270,11 +270,22 @@ EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery);
int i2c_recover_bus(struct i2c_adapter *adap)
{
+
+ if (adap->stats == NULL)
+ i2c_adapter_create_stats_directory(adap);
+
if (!adap->bus_recovery_info)
return -EBUSY;
dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
- return adap->bus_recovery_info->recover_bus(adap);
+ int ret = adap->bus_recovery_info->recover_bus(adap);
+
+ if (ret == 0)
+ ++(adap->stats->recovery_successes);
+ else
+ ++(adap->stats->recovery_failures);
+
+ return ret;
}
EXPORT_SYMBOL_GPL(i2c_recover_bus);
@@ -2223,6 +2234,23 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
trace_i2c_result(adap, num, ret);
}
+ if (adap->stats == NULL) {
+ i2c_adapter_create_stats_directory(adap);
+ }
+
+ if (ret < 0) {
+ if (ret == -ENXIO)
+ ++(adap->stats->nacks);
+ else if (ret == -ETIMEDOUT)
+ ++(adap->stats->timeouts);
+ else
+ ++(adap->stats->bus_errors);
+ }
+
+ if (ret == num) {
+ ++(adap->stats->transfers);
+ }
+
return ret;
}
EXPORT_SYMBOL(__i2c_transfer);
@@ -2485,6 +2513,7 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
}
kfree(temp_client);
+ i2c_adapter_create_stats_directory(adapter);
return err;
}
@@ -2617,6 +2646,7 @@ void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred)
kfree(buf);
}
+
EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf);
MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index 77f576e51652..253622706b63 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -767,6 +767,100 @@ static void __exit i2c_dev_exit(void)
unregister_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS);
}
+static struct i2c_adapter *kobj_to_adapter(struct device *pdev)
+{
+ struct kobject *dev_kobj;
+ struct device *dev;
+
+ dev_kobj = ((struct kobject *)pdev)->parent;
+ dev = container_of(dev_kobj, struct device, kobj);
+ return to_i2c_adapter(dev);
+}
+
+ssize_t bus_errors_show(struct device *pdev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->bus_errors);
+}
+DEVICE_ATTR_RO(bus_errors);
+
+ssize_t transfers_show(struct device *pdev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->transfers);
+}
+DEVICE_ATTR_RO(transfers);
+
+ssize_t nacks_show(struct device *pdev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->nacks);
+}
+DEVICE_ATTR_RO(nacks);
+
+ssize_t recovery_successes_show(struct device *pdev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_successes);
+}
+DEVICE_ATTR_RO(recovery_successes);
+
+ssize_t recovery_failures_show(struct device *pdev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_failures);
+}
+DEVICE_ATTR_RO(recovery_failures);
+
+ssize_t timeouts_show(struct device *pdev,
+ struct device_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->timeouts);
+}
+DEVICE_ATTR_RO(timeouts);
+
+/**
+ * i2c_adapter_create_stats_directory - creates folder for I2C statistics.
+ * @adapter: the i2c_adapter to create the stats directory for.
+ *
+ * Return: 0 if successful, 1 if failed.
+ */
+int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter)
+{
+ struct i2c_adapter_stats *stats;
+ int ret = 1;
+
+ stats = kzalloc(sizeof(*stats), GFP_KERNEL);
+ if (!stats) {
+ adapter->stats = NULL;
+ return ret;
+ }
+ adapter->stats = stats;
+ adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj);
+
+ ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_transfers.attr);
+ if (ret)
+ dev_warn(&adapter->dev, "Failed to create sysfs file for tx_complete_cnt\n");
+
+ ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_bus_errors.attr);
+ if (ret)
+ dev_warn(&adapter->dev, "Failed to create sysfs file for bus_errors\n");
+
+ ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nacks.attr);
+ if (ret)
+ dev_warn(&adapter->dev, "Failed to create sysfs file for nacks\n");
+
+ ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_successes.attr);
+ if (ret)
+ dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_successes\n");
+
+ ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_failures.attr);
+ if (ret)
+ dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_failures\n");
+
+ return ret;
+}
+
MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
MODULE_DESCRIPTION("I2C /dev entries driver");
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 3eb60a2e9e61..c8608378da2a 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -21,6 +21,7 @@
#include <linux/of.h> /* for struct device_node */
#include <linux/swab.h> /* for swab16 */
#include <uapi/linux/i2c.h>
+#include <linux/slab.h> /* for kzalloc */
extern struct bus_type i2c_bus_type;
extern struct device_type i2c_adapter_type;
@@ -684,6 +685,25 @@ struct i2c_adapter_quirks {
u16 max_comb_2nd_msg_len;
};
+/**
+ * I2C statistics
+ * The list of statistics are currently copied from npcm7xx.
+ * Perhaps a more universal set of statistics can be used.
+ *
+ * The stats are currently modeled as pointers to members in the bus drivers.
+ * A null pointer indicates the counter is not supported by the bus driver.
+ */
+struct i2c_adapter_stats {
+ struct kobject *kobj;
+
+ u64 transfers;
+ u64 bus_errors;
+ u64 nacks;
+ u64 recovery_successes;
+ u64 recovery_failures;
+ u64 timeouts;
+};
+
/* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */
#define I2C_AQ_COMB BIT(0)
/* first combined message must be write */
@@ -735,12 +755,18 @@ struct i2c_adapter {
struct i2c_bus_recovery_info *bus_recovery_info;
const struct i2c_adapter_quirks *quirks;
+ struct i2c_adapter_stats *stats;
struct irq_domain *host_notify_domain;
struct regulator *bus_regulator;
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
+int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter);
+
+void i2c_adapter_stats_register_counter(struct i2c_adapter *adapter,
+ const char *counter_name, void *data_source);
+
static inline void *i2c_get_adapdata(const struct i2c_adapter *adap)
{
return dev_get_drvdata(&adap->dev);
--
2.35.1.1094.g7c7d902a7c-goog
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [RFC Patch v4 1/1] i2c debug counters as sysfs attributes
2022-04-01 0:22 ` [RFC Patch v4 1/1] i2c debug counters " Sui Chen
@ 2022-04-03 12:12 ` Avi Fishman
2022-04-12 6:57 ` Sui Chen
0 siblings, 1 reply; 5+ messages in thread
From: Avi Fishman @ 2022-04-03 12:12 UTC (permalink / raw)
To: Sui Chen
Cc: Benjamin Fair, Andrew Jeffery, OpenBMC Maillist, Tali Perry,
krellan, linux-i2c, Joel Stanley
Hi Sui,
Do you intend later to push it also to kernel.org?
Avi
On Fri, Apr 1, 2022 at 3:28 AM Sui Chen <suichen@google.com> wrote:
>
> This change renames the I2C debug counters as suggested, and moves their
> processing into the i2c core:
> - bus_errors
> - transfers
> - nacks
> - recovery_successes
> - recovery_failures
> - timeouts
>
> The function i2c_adapter_create_stats_folder creates a stats directory
> in the device's sysfs directory to hold the above debug counters.
>
> Did some brief tests with a few test programs that saves/replays I2C
> trace by reading hwmon sensors. The test program and hardware run in
> QEMU. The test programs are located at
> https://gerrit.openbmc-project.xyz/c/openbmc/openbmc-tools/+/52527
>
> (A normal read)
>
> root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> 264
> root@gsj:/tmp# ./i2c_bmk_bmc 0
> idx=0
> Processing 1 inputs
> /sys/class/hwmon/hwmon0/temp1_input
> (../../devices/platform/ahb/ahb:apb/f0081000.i2c/i2c-1/1-005c/hwmon/hwmon0):
> 0
> [FindTraceEntries] t0=391.000000 t1=393.000000
> Found 4 interesting I2C trace entries:
> i2c_write: i2c-1 #0 a=05c f=0000 l=1 [00]
> i2c_read: i2c-1 #1 a=05c f=0001 l=2
> i2c_reply: i2c-1 #1 a=05c f=0001 l=2 [00-00]
> i2c_result: i2c-1 n=2 ret=2
> root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> 265
>
> (Read from an inexistent address, NACK)
>
> root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
> 6
> root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> 265
>
> root@gsj:/tmp# cat i2c_trace.txt
> i2c_write: i2c-1 #0 a=0ff f=0000 l=1 [00]
> i2c_read: i2c-1 #1 a=0ff f=0001 l=2
> root@gsj:/tmp# ./i2c_replay_bmc i2c_trace.txt
> (program runs and completes)
>
> root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
> 12
> root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> 265
>
> The program makes 2 attempts, performing 3 I2C operations at each
> attempt, which translates to the 6 nack events.
>
> Signed-off-by: Sui Chen <suichen@google.com>
> ---
> drivers/i2c/i2c-core-base.c | 32 ++++++++++++-
> drivers/i2c/i2c-dev.c | 94 +++++++++++++++++++++++++++++++++++++
> include/linux/i2c.h | 26 ++++++++++
> 3 files changed, 151 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> index 84f12bf90644..53688b1d855a 100644
> --- a/drivers/i2c/i2c-core-base.c
> +++ b/drivers/i2c/i2c-core-base.c
> @@ -270,11 +270,22 @@ EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery);
>
> int i2c_recover_bus(struct i2c_adapter *adap)
> {
> +
> + if (adap->stats == NULL)
> + i2c_adapter_create_stats_directory(adap);
> +
> if (!adap->bus_recovery_info)
> return -EBUSY;
>
> dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
> - return adap->bus_recovery_info->recover_bus(adap);
> + int ret = adap->bus_recovery_info->recover_bus(adap);
> +
> + if (ret == 0)
> + ++(adap->stats->recovery_successes);
> + else
> + ++(adap->stats->recovery_failures);
> +
> + return ret;
> }
> EXPORT_SYMBOL_GPL(i2c_recover_bus);
>
> @@ -2223,6 +2234,23 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
> trace_i2c_result(adap, num, ret);
> }
>
> + if (adap->stats == NULL) {
> + i2c_adapter_create_stats_directory(adap);
> + }
> +
> + if (ret < 0) {
> + if (ret == -ENXIO)
> + ++(adap->stats->nacks);
> + else if (ret == -ETIMEDOUT)
> + ++(adap->stats->timeouts);
> + else
> + ++(adap->stats->bus_errors);
> + }
> +
> + if (ret == num) {
> + ++(adap->stats->transfers);
> + }
> +
> return ret;
> }
> EXPORT_SYMBOL(__i2c_transfer);
> @@ -2485,6 +2513,7 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
> }
>
> kfree(temp_client);
> + i2c_adapter_create_stats_directory(adapter);
> return err;
> }
>
> @@ -2617,6 +2646,7 @@ void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred)
>
> kfree(buf);
> }
> +
> EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf);
>
> MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
> diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
> index 77f576e51652..253622706b63 100644
> --- a/drivers/i2c/i2c-dev.c
> +++ b/drivers/i2c/i2c-dev.c
> @@ -767,6 +767,100 @@ static void __exit i2c_dev_exit(void)
> unregister_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS);
> }
>
> +static struct i2c_adapter *kobj_to_adapter(struct device *pdev)
> +{
> + struct kobject *dev_kobj;
> + struct device *dev;
> +
> + dev_kobj = ((struct kobject *)pdev)->parent;
> + dev = container_of(dev_kobj, struct device, kobj);
> + return to_i2c_adapter(dev);
> +}
> +
> +ssize_t bus_errors_show(struct device *pdev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->bus_errors);
> +}
> +DEVICE_ATTR_RO(bus_errors);
> +
> +ssize_t transfers_show(struct device *pdev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->transfers);
> +}
> +DEVICE_ATTR_RO(transfers);
> +
> +ssize_t nacks_show(struct device *pdev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->nacks);
> +}
> +DEVICE_ATTR_RO(nacks);
> +
> +ssize_t recovery_successes_show(struct device *pdev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_successes);
> +}
> +DEVICE_ATTR_RO(recovery_successes);
> +
> +ssize_t recovery_failures_show(struct device *pdev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_failures);
> +}
> +DEVICE_ATTR_RO(recovery_failures);
> +
> +ssize_t timeouts_show(struct device *pdev,
> + struct device_attribute *attr, char *buf)
> +{
> + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->timeouts);
> +}
> +DEVICE_ATTR_RO(timeouts);
> +
> +/**
> + * i2c_adapter_create_stats_directory - creates folder for I2C statistics.
> + * @adapter: the i2c_adapter to create the stats directory for.
> + *
> + * Return: 0 if successful, 1 if failed.
> + */
> +int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter)
> +{
> + struct i2c_adapter_stats *stats;
> + int ret = 1;
> +
> + stats = kzalloc(sizeof(*stats), GFP_KERNEL);
> + if (!stats) {
> + adapter->stats = NULL;
> + return ret;
> + }
> + adapter->stats = stats;
> + adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj);
> +
> + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_transfers.attr);
> + if (ret)
> + dev_warn(&adapter->dev, "Failed to create sysfs file for tx_complete_cnt\n");
> +
> + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_bus_errors.attr);
> + if (ret)
> + dev_warn(&adapter->dev, "Failed to create sysfs file for bus_errors\n");
> +
> + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nacks.attr);
> + if (ret)
> + dev_warn(&adapter->dev, "Failed to create sysfs file for nacks\n");
> +
> + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_successes.attr);
> + if (ret)
> + dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_successes\n");
> +
> + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_failures.attr);
> + if (ret)
> + dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_failures\n");
> +
> + return ret;
> +}
> +
> MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
> MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
> MODULE_DESCRIPTION("I2C /dev entries driver");
> diff --git a/include/linux/i2c.h b/include/linux/i2c.h
> index 3eb60a2e9e61..c8608378da2a 100644
> --- a/include/linux/i2c.h
> +++ b/include/linux/i2c.h
> @@ -21,6 +21,7 @@
> #include <linux/of.h> /* for struct device_node */
> #include <linux/swab.h> /* for swab16 */
> #include <uapi/linux/i2c.h>
> +#include <linux/slab.h> /* for kzalloc */
>
> extern struct bus_type i2c_bus_type;
> extern struct device_type i2c_adapter_type;
> @@ -684,6 +685,25 @@ struct i2c_adapter_quirks {
> u16 max_comb_2nd_msg_len;
> };
>
> +/**
> + * I2C statistics
> + * The list of statistics are currently copied from npcm7xx.
> + * Perhaps a more universal set of statistics can be used.
> + *
> + * The stats are currently modeled as pointers to members in the bus drivers.
> + * A null pointer indicates the counter is not supported by the bus driver.
> + */
> +struct i2c_adapter_stats {
> + struct kobject *kobj;
> +
> + u64 transfers;
> + u64 bus_errors;
> + u64 nacks;
> + u64 recovery_successes;
> + u64 recovery_failures;
> + u64 timeouts;
> +};
> +
> /* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */
> #define I2C_AQ_COMB BIT(0)
> /* first combined message must be write */
> @@ -735,12 +755,18 @@ struct i2c_adapter {
>
> struct i2c_bus_recovery_info *bus_recovery_info;
> const struct i2c_adapter_quirks *quirks;
> + struct i2c_adapter_stats *stats;
>
> struct irq_domain *host_notify_domain;
> struct regulator *bus_regulator;
> };
> #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
>
> +int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter);
> +
> +void i2c_adapter_stats_register_counter(struct i2c_adapter *adapter,
> + const char *counter_name, void *data_source);
> +
> static inline void *i2c_get_adapdata(const struct i2c_adapter *adap)
> {
> return dev_get_drvdata(&adap->dev);
> --
> 2.35.1.1094.g7c7d902a7c-goog
>
--
Regards,
Avi
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [RFC Patch v4 1/1] i2c debug counters as sysfs attributes
2022-04-03 12:12 ` Avi Fishman
@ 2022-04-12 6:57 ` Sui Chen
2022-04-12 15:38 ` Avi Fishman
0 siblings, 1 reply; 5+ messages in thread
From: Sui Chen @ 2022-04-12 6:57 UTC (permalink / raw)
To: Avi Fishman
Cc: Benjamin Fair, Andrew Jeffery, OpenBMC Maillist, Tali Perry,
Josh Lehan, linux-i2c, Joel Stanley
Hello Avi,
I recently installed a patched kernel on a real machine and am trying
to validate the counters a bit; I would like to find out how the
counters in the i2c core relate to the counters in the npcm7xx driver,
and also explore the possibility of per-address counters, then update
to this list and the linux-kernel list when the results are clear.
And also I need to find a better place to create the sysfs folders
than from within i2c_transfer and i2c_recover_bus.
Thanks,
Sui
On Sun, Apr 3, 2022 at 5:12 AM Avi Fishman <avifishman70@gmail.com> wrote:
>
> Hi Sui,
>
> Do you intend later to push it also to kernel.org?
>
> Avi
>
> On Fri, Apr 1, 2022 at 3:28 AM Sui Chen <suichen@google.com> wrote:
> >
> > This change renames the I2C debug counters as suggested, and moves their
> > processing into the i2c core:
> > - bus_errors
> > - transfers
> > - nacks
> > - recovery_successes
> > - recovery_failures
> > - timeouts
> >
> > The function i2c_adapter_create_stats_folder creates a stats directory
> > in the device's sysfs directory to hold the above debug counters.
> >
> > Did some brief tests with a few test programs that saves/replays I2C
> > trace by reading hwmon sensors. The test program and hardware run in
> > QEMU. The test programs are located at
> > https://gerrit.openbmc-project.xyz/c/openbmc/openbmc-tools/+/52527
> >
> > (A normal read)
> >
> > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > 264
> > root@gsj:/tmp# ./i2c_bmk_bmc 0
> > idx=0
> > Processing 1 inputs
> > /sys/class/hwmon/hwmon0/temp1_input
> > (../../devices/platform/ahb/ahb:apb/f0081000.i2c/i2c-1/1-005c/hwmon/hwmon0):
> > 0
> > [FindTraceEntries] t0=391.000000 t1=393.000000
> > Found 4 interesting I2C trace entries:
> > i2c_write: i2c-1 #0 a=05c f=0000 l=1 [00]
> > i2c_read: i2c-1 #1 a=05c f=0001 l=2
> > i2c_reply: i2c-1 #1 a=05c f=0001 l=2 [00-00]
> > i2c_result: i2c-1 n=2 ret=2
> > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > 265
> >
> > (Read from an inexistent address, NACK)
> >
> > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
> > 6
> > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > 265
> >
> > root@gsj:/tmp# cat i2c_trace.txt
> > i2c_write: i2c-1 #0 a=0ff f=0000 l=1 [00]
> > i2c_read: i2c-1 #1 a=0ff f=0001 l=2
> > root@gsj:/tmp# ./i2c_replay_bmc i2c_trace.txt
> > (program runs and completes)
> >
> > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
> > 12
> > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > 265
> >
> > The program makes 2 attempts, performing 3 I2C operations at each
> > attempt, which translates to the 6 nack events.
> >
> > Signed-off-by: Sui Chen <suichen@google.com>
> > ---
> > drivers/i2c/i2c-core-base.c | 32 ++++++++++++-
> > drivers/i2c/i2c-dev.c | 94 +++++++++++++++++++++++++++++++++++++
> > include/linux/i2c.h | 26 ++++++++++
> > 3 files changed, 151 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> > index 84f12bf90644..53688b1d855a 100644
> > --- a/drivers/i2c/i2c-core-base.c
> > +++ b/drivers/i2c/i2c-core-base.c
> > @@ -270,11 +270,22 @@ EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery);
> >
> > int i2c_recover_bus(struct i2c_adapter *adap)
> > {
> > +
> > + if (adap->stats == NULL)
> > + i2c_adapter_create_stats_directory(adap);
> > +
> > if (!adap->bus_recovery_info)
> > return -EBUSY;
> >
> > dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
> > - return adap->bus_recovery_info->recover_bus(adap);
> > + int ret = adap->bus_recovery_info->recover_bus(adap);
> > +
> > + if (ret == 0)
> > + ++(adap->stats->recovery_successes);
> > + else
> > + ++(adap->stats->recovery_failures);
> > +
> > + return ret;
> > }
> > EXPORT_SYMBOL_GPL(i2c_recover_bus);
> >
> > @@ -2223,6 +2234,23 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
> > trace_i2c_result(adap, num, ret);
> > }
> >
> > + if (adap->stats == NULL) {
> > + i2c_adapter_create_stats_directory(adap);
> > + }
> > +
> > + if (ret < 0) {
> > + if (ret == -ENXIO)
> > + ++(adap->stats->nacks);
> > + else if (ret == -ETIMEDOUT)
> > + ++(adap->stats->timeouts);
> > + else
> > + ++(adap->stats->bus_errors);
> > + }
> > +
> > + if (ret == num) {
> > + ++(adap->stats->transfers);
> > + }
> > +
> > return ret;
> > }
> > EXPORT_SYMBOL(__i2c_transfer);
> > @@ -2485,6 +2513,7 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
> > }
> >
> > kfree(temp_client);
> > + i2c_adapter_create_stats_directory(adapter);
> > return err;
> > }
> >
> > @@ -2617,6 +2646,7 @@ void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred)
> >
> > kfree(buf);
> > }
> > +
> > EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf);
> >
> > MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
> > diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
> > index 77f576e51652..253622706b63 100644
> > --- a/drivers/i2c/i2c-dev.c
> > +++ b/drivers/i2c/i2c-dev.c
> > @@ -767,6 +767,100 @@ static void __exit i2c_dev_exit(void)
> > unregister_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS);
> > }
> >
> > +static struct i2c_adapter *kobj_to_adapter(struct device *pdev)
> > +{
> > + struct kobject *dev_kobj;
> > + struct device *dev;
> > +
> > + dev_kobj = ((struct kobject *)pdev)->parent;
> > + dev = container_of(dev_kobj, struct device, kobj);
> > + return to_i2c_adapter(dev);
> > +}
> > +
> > +ssize_t bus_errors_show(struct device *pdev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->bus_errors);
> > +}
> > +DEVICE_ATTR_RO(bus_errors);
> > +
> > +ssize_t transfers_show(struct device *pdev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->transfers);
> > +}
> > +DEVICE_ATTR_RO(transfers);
> > +
> > +ssize_t nacks_show(struct device *pdev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->nacks);
> > +}
> > +DEVICE_ATTR_RO(nacks);
> > +
> > +ssize_t recovery_successes_show(struct device *pdev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_successes);
> > +}
> > +DEVICE_ATTR_RO(recovery_successes);
> > +
> > +ssize_t recovery_failures_show(struct device *pdev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_failures);
> > +}
> > +DEVICE_ATTR_RO(recovery_failures);
> > +
> > +ssize_t timeouts_show(struct device *pdev,
> > + struct device_attribute *attr, char *buf)
> > +{
> > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->timeouts);
> > +}
> > +DEVICE_ATTR_RO(timeouts);
> > +
> > +/**
> > + * i2c_adapter_create_stats_directory - creates folder for I2C statistics.
> > + * @adapter: the i2c_adapter to create the stats directory for.
> > + *
> > + * Return: 0 if successful, 1 if failed.
> > + */
> > +int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter)
> > +{
> > + struct i2c_adapter_stats *stats;
> > + int ret = 1;
> > +
> > + stats = kzalloc(sizeof(*stats), GFP_KERNEL);
> > + if (!stats) {
> > + adapter->stats = NULL;
> > + return ret;
> > + }
> > + adapter->stats = stats;
> > + adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj);
> > +
> > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_transfers.attr);
> > + if (ret)
> > + dev_warn(&adapter->dev, "Failed to create sysfs file for tx_complete_cnt\n");
> > +
> > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_bus_errors.attr);
> > + if (ret)
> > + dev_warn(&adapter->dev, "Failed to create sysfs file for bus_errors\n");
> > +
> > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nacks.attr);
> > + if (ret)
> > + dev_warn(&adapter->dev, "Failed to create sysfs file for nacks\n");
> > +
> > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_successes.attr);
> > + if (ret)
> > + dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_successes\n");
> > +
> > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_failures.attr);
> > + if (ret)
> > + dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_failures\n");
> > +
> > + return ret;
> > +}
> > +
> > MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
> > MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
> > MODULE_DESCRIPTION("I2C /dev entries driver");
> > diff --git a/include/linux/i2c.h b/include/linux/i2c.h
> > index 3eb60a2e9e61..c8608378da2a 100644
> > --- a/include/linux/i2c.h
> > +++ b/include/linux/i2c.h
> > @@ -21,6 +21,7 @@
> > #include <linux/of.h> /* for struct device_node */
> > #include <linux/swab.h> /* for swab16 */
> > #include <uapi/linux/i2c.h>
> > +#include <linux/slab.h> /* for kzalloc */
> >
> > extern struct bus_type i2c_bus_type;
> > extern struct device_type i2c_adapter_type;
> > @@ -684,6 +685,25 @@ struct i2c_adapter_quirks {
> > u16 max_comb_2nd_msg_len;
> > };
> >
> > +/**
> > + * I2C statistics
> > + * The list of statistics are currently copied from npcm7xx.
> > + * Perhaps a more universal set of statistics can be used.
> > + *
> > + * The stats are currently modeled as pointers to members in the bus drivers.
> > + * A null pointer indicates the counter is not supported by the bus driver.
> > + */
> > +struct i2c_adapter_stats {
> > + struct kobject *kobj;
> > +
> > + u64 transfers;
> > + u64 bus_errors;
> > + u64 nacks;
> > + u64 recovery_successes;
> > + u64 recovery_failures;
> > + u64 timeouts;
> > +};
> > +
> > /* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */
> > #define I2C_AQ_COMB BIT(0)
> > /* first combined message must be write */
> > @@ -735,12 +755,18 @@ struct i2c_adapter {
> >
> > struct i2c_bus_recovery_info *bus_recovery_info;
> > const struct i2c_adapter_quirks *quirks;
> > + struct i2c_adapter_stats *stats;
> >
> > struct irq_domain *host_notify_domain;
> > struct regulator *bus_regulator;
> > };
> > #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
> >
> > +int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter);
> > +
> > +void i2c_adapter_stats_register_counter(struct i2c_adapter *adapter,
> > + const char *counter_name, void *data_source);
> > +
> > static inline void *i2c_get_adapdata(const struct i2c_adapter *adap)
> > {
> > return dev_get_drvdata(&adap->dev);
> > --
> > 2.35.1.1094.g7c7d902a7c-goog
> >
>
>
> --
> Regards,
> Avi
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [RFC Patch v4 1/1] i2c debug counters as sysfs attributes
2022-04-12 6:57 ` Sui Chen
@ 2022-04-12 15:38 ` Avi Fishman
0 siblings, 0 replies; 5+ messages in thread
From: Avi Fishman @ 2022-04-12 15:38 UTC (permalink / raw)
To: Sui Chen
Cc: Benjamin Fair, Andrew Jeffery, OpenBMC Maillist, Tomer Maimon,
Tali Perry, krellan, Joel Stanley, Tyrone Ting, linux-i2c
Hi Sui
I am not sure that there is a standard that returning -ENXIO means
always NACK, and I am not sure that there are no other cases where we
return -ENXIO which is not NACK, unless you are asking for local
modification that will not be upstreamed.
Also you can know the per-address counters via the 'adap' stract you
use for transfer.
Thanks,
Avi
On Tue, Apr 12, 2022 at 9:57 AM Sui Chen <suichen@google.com> wrote:
>
> Hello Avi,
>
> I recently installed a patched kernel on a real machine and am trying
> to validate the counters a bit; I would like to find out how the
> counters in the i2c core relate to the counters in the npcm7xx driver,
> and also explore the possibility of per-address counters, then update
> to this list and the linux-kernel list when the results are clear.
>
> And also I need to find a better place to create the sysfs folders
> than from within i2c_transfer and i2c_recover_bus.
>
> Thanks,
> Sui
>
>
> On Sun, Apr 3, 2022 at 5:12 AM Avi Fishman <avifishman70@gmail.com> wrote:
> >
> > Hi Sui,
> >
> > Do you intend later to push it also to kernel.org?
> >
> > Avi
> >
> > On Fri, Apr 1, 2022 at 3:28 AM Sui Chen <suichen@google.com> wrote:
> > >
> > > This change renames the I2C debug counters as suggested, and moves their
> > > processing into the i2c core:
> > > - bus_errors
> > > - transfers
> > > - nacks
> > > - recovery_successes
> > > - recovery_failures
> > > - timeouts
> > >
> > > The function i2c_adapter_create_stats_folder creates a stats directory
> > > in the device's sysfs directory to hold the above debug counters.
> > >
> > > Did some brief tests with a few test programs that saves/replays I2C
> > > trace by reading hwmon sensors. The test program and hardware run in
> > > QEMU. The test programs are located at
> > > https://gerrit.openbmc-project.xyz/c/openbmc/openbmc-tools/+/52527
> > >
> > > (A normal read)
> > >
> > > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > > 264
> > > root@gsj:/tmp# ./i2c_bmk_bmc 0
> > > idx=0
> > > Processing 1 inputs
> > > /sys/class/hwmon/hwmon0/temp1_input
> > > (../../devices/platform/ahb/ahb:apb/f0081000.i2c/i2c-1/1-005c/hwmon/hwmon0):
> > > 0
> > > [FindTraceEntries] t0=391.000000 t1=393.000000
> > > Found 4 interesting I2C trace entries:
> > > i2c_write: i2c-1 #0 a=05c f=0000 l=1 [00]
> > > i2c_read: i2c-1 #1 a=05c f=0001 l=2
> > > i2c_reply: i2c-1 #1 a=05c f=0001 l=2 [00-00]
> > > i2c_result: i2c-1 n=2 ret=2
> > > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > > 265
> > >
> > > (Read from an inexistent address, NACK)
> > >
> > > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
> > > 6
> > > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > > 265
> > >
> > > root@gsj:/tmp# cat i2c_trace.txt
> > > i2c_write: i2c-1 #0 a=0ff f=0000 l=1 [00]
> > > i2c_read: i2c-1 #1 a=0ff f=0001 l=2
> > > root@gsj:/tmp# ./i2c_replay_bmc i2c_trace.txt
> > > (program runs and completes)
> > >
> > > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/nacks
> > > 12
> > > root@gsj:/tmp# cat /sys/class/i2c-adapter/i2c-1/stats/transfers
> > > 265
> > >
> > > The program makes 2 attempts, performing 3 I2C operations at each
> > > attempt, which translates to the 6 nack events.
> > >
> > > Signed-off-by: Sui Chen <suichen@google.com>
> > > ---
> > > drivers/i2c/i2c-core-base.c | 32 ++++++++++++-
> > > drivers/i2c/i2c-dev.c | 94 +++++++++++++++++++++++++++++++++++++
> > > include/linux/i2c.h | 26 ++++++++++
> > > 3 files changed, 151 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
> > > index 84f12bf90644..53688b1d855a 100644
> > > --- a/drivers/i2c/i2c-core-base.c
> > > +++ b/drivers/i2c/i2c-core-base.c
> > > @@ -270,11 +270,22 @@ EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery);
> > >
> > > int i2c_recover_bus(struct i2c_adapter *adap)
> > > {
> > > +
> > > + if (adap->stats == NULL)
> > > + i2c_adapter_create_stats_directory(adap);
> > > +
> > > if (!adap->bus_recovery_info)
> > > return -EBUSY;
> > >
> > > dev_dbg(&adap->dev, "Trying i2c bus recovery\n");
> > > - return adap->bus_recovery_info->recover_bus(adap);
> > > + int ret = adap->bus_recovery_info->recover_bus(adap);
> > > +
> > > + if (ret == 0)
> > > + ++(adap->stats->recovery_successes);
> > > + else
> > > + ++(adap->stats->recovery_failures);
> > > +
> > > + return ret;
> > > }
> > > EXPORT_SYMBOL_GPL(i2c_recover_bus);
> > >
> > > @@ -2223,6 +2234,23 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
> > > trace_i2c_result(adap, num, ret);
> > > }
> > >
> > > + if (adap->stats == NULL) {
> > > + i2c_adapter_create_stats_directory(adap);
> > > + }
> > > +
> > > + if (ret < 0) {
> > > + if (ret == -ENXIO)
> > > + ++(adap->stats->nacks);
> > > + else if (ret == -ETIMEDOUT)
> > > + ++(adap->stats->timeouts);
> > > + else
> > > + ++(adap->stats->bus_errors);
> > > + }
> > > +
> > > + if (ret == num) {
> > > + ++(adap->stats->transfers);
> > > + }
> > > +
> > > return ret;
> > > }
> > > EXPORT_SYMBOL(__i2c_transfer);
> > > @@ -2485,6 +2513,7 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
> > > }
> > >
> > > kfree(temp_client);
> > > + i2c_adapter_create_stats_directory(adapter);
> > > return err;
> > > }
> > >
> > > @@ -2617,6 +2646,7 @@ void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred)
> > >
> > > kfree(buf);
> > > }
> > > +
> > > EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf);
> > >
> > > MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
> > > diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
> > > index 77f576e51652..253622706b63 100644
> > > --- a/drivers/i2c/i2c-dev.c
> > > +++ b/drivers/i2c/i2c-dev.c
> > > @@ -767,6 +767,100 @@ static void __exit i2c_dev_exit(void)
> > > unregister_chrdev_region(MKDEV(I2C_MAJOR, 0), I2C_MINORS);
> > > }
> > >
> > > +static struct i2c_adapter *kobj_to_adapter(struct device *pdev)
> > > +{
> > > + struct kobject *dev_kobj;
> > > + struct device *dev;
> > > +
> > > + dev_kobj = ((struct kobject *)pdev)->parent;
> > > + dev = container_of(dev_kobj, struct device, kobj);
> > > + return to_i2c_adapter(dev);
> > > +}
> > > +
> > > +ssize_t bus_errors_show(struct device *pdev,
> > > + struct device_attribute *attr, char *buf)
> > > +{
> > > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->bus_errors);
> > > +}
> > > +DEVICE_ATTR_RO(bus_errors);
> > > +
> > > +ssize_t transfers_show(struct device *pdev,
> > > + struct device_attribute *attr, char *buf)
> > > +{
> > > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->transfers);
> > > +}
> > > +DEVICE_ATTR_RO(transfers);
> > > +
> > > +ssize_t nacks_show(struct device *pdev,
> > > + struct device_attribute *attr, char *buf)
> > > +{
> > > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->nacks);
> > > +}
> > > +DEVICE_ATTR_RO(nacks);
> > > +
> > > +ssize_t recovery_successes_show(struct device *pdev,
> > > + struct device_attribute *attr, char *buf)
> > > +{
> > > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_successes);
> > > +}
> > > +DEVICE_ATTR_RO(recovery_successes);
> > > +
> > > +ssize_t recovery_failures_show(struct device *pdev,
> > > + struct device_attribute *attr, char *buf)
> > > +{
> > > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->recovery_failures);
> > > +}
> > > +DEVICE_ATTR_RO(recovery_failures);
> > > +
> > > +ssize_t timeouts_show(struct device *pdev,
> > > + struct device_attribute *attr, char *buf)
> > > +{
> > > + return sysfs_emit(buf, "%llu\n", kobj_to_adapter(pdev)->stats->timeouts);
> > > +}
> > > +DEVICE_ATTR_RO(timeouts);
> > > +
> > > +/**
> > > + * i2c_adapter_create_stats_directory - creates folder for I2C statistics.
> > > + * @adapter: the i2c_adapter to create the stats directory for.
> > > + *
> > > + * Return: 0 if successful, 1 if failed.
> > > + */
> > > +int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter)
> > > +{
> > > + struct i2c_adapter_stats *stats;
> > > + int ret = 1;
> > > +
> > > + stats = kzalloc(sizeof(*stats), GFP_KERNEL);
> > > + if (!stats) {
> > > + adapter->stats = NULL;
> > > + return ret;
> > > + }
> > > + adapter->stats = stats;
> > > + adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj);
> > > +
> > > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_transfers.attr);
> > > + if (ret)
> > > + dev_warn(&adapter->dev, "Failed to create sysfs file for tx_complete_cnt\n");
> > > +
> > > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_bus_errors.attr);
> > > + if (ret)
> > > + dev_warn(&adapter->dev, "Failed to create sysfs file for bus_errors\n");
> > > +
> > > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nacks.attr);
> > > + if (ret)
> > > + dev_warn(&adapter->dev, "Failed to create sysfs file for nacks\n");
> > > +
> > > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_successes.attr);
> > > + if (ret)
> > > + dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_successes\n");
> > > +
> > > + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_recovery_failures.attr);
> > > + if (ret)
> > > + dev_warn(&adapter->dev, "Failed to create sysfs file for recovery_failures\n");
> > > +
> > > + return ret;
> > > +}
> > > +
> > > MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
> > > MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
> > > MODULE_DESCRIPTION("I2C /dev entries driver");
> > > diff --git a/include/linux/i2c.h b/include/linux/i2c.h
> > > index 3eb60a2e9e61..c8608378da2a 100644
> > > --- a/include/linux/i2c.h
> > > +++ b/include/linux/i2c.h
> > > @@ -21,6 +21,7 @@
> > > #include <linux/of.h> /* for struct device_node */
> > > #include <linux/swab.h> /* for swab16 */
> > > #include <uapi/linux/i2c.h>
> > > +#include <linux/slab.h> /* for kzalloc */
> > >
> > > extern struct bus_type i2c_bus_type;
> > > extern struct device_type i2c_adapter_type;
> > > @@ -684,6 +685,25 @@ struct i2c_adapter_quirks {
> > > u16 max_comb_2nd_msg_len;
> > > };
> > >
> > > +/**
> > > + * I2C statistics
> > > + * The list of statistics are currently copied from npcm7xx.
> > > + * Perhaps a more universal set of statistics can be used.
> > > + *
> > > + * The stats are currently modeled as pointers to members in the bus drivers.
> > > + * A null pointer indicates the counter is not supported by the bus driver.
> > > + */
> > > +struct i2c_adapter_stats {
> > > + struct kobject *kobj;
> > > +
> > > + u64 transfers;
> > > + u64 bus_errors;
> > > + u64 nacks;
> > > + u64 recovery_successes;
> > > + u64 recovery_failures;
> > > + u64 timeouts;
> > > +};
> > > +
> > > /* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */
> > > #define I2C_AQ_COMB BIT(0)
> > > /* first combined message must be write */
> > > @@ -735,12 +755,18 @@ struct i2c_adapter {
> > >
> > > struct i2c_bus_recovery_info *bus_recovery_info;
> > > const struct i2c_adapter_quirks *quirks;
> > > + struct i2c_adapter_stats *stats;
> > >
> > > struct irq_domain *host_notify_domain;
> > > struct regulator *bus_regulator;
> > > };
> > > #define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
> > >
> > > +int i2c_adapter_create_stats_directory(struct i2c_adapter *adapter);
> > > +
> > > +void i2c_adapter_stats_register_counter(struct i2c_adapter *adapter,
> > > + const char *counter_name, void *data_source);
> > > +
> > > static inline void *i2c_get_adapdata(const struct i2c_adapter *adap)
> > > {
> > > return dev_get_drvdata(&adap->dev);
> > > --
> > > 2.35.1.1094.g7c7d902a7c-goog
> > >
> >
> >
> > --
> > Regards,
> > Avi
--
Regards,
Avi
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2022-04-12 15:39 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-04-01 0:21 [RFC Patch v4 0/1] i2c statistics as sysfs attributes Sui Chen
2022-04-01 0:22 ` [RFC Patch v4 1/1] i2c debug counters " Sui Chen
2022-04-03 12:12 ` Avi Fishman
2022-04-12 6:57 ` Sui Chen
2022-04-12 15:38 ` Avi Fishman
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).