This change adds a few example I2C debug counters as sysfs attributes: - ber_cnt (bus error count) - nack_cnt (NACK count) - rec_fail_cnt, rec_succ_cnt (recovery failure/success count) - timeout_cnt (timeout count) - i2c_speed (bus frequency) - tx_complete_cnt (transaction completed, including both as an initiator and as a target) The function i2c_adapter_create_stats_folder creates a stats directory in the device's sysfs directory to hold the debug counters. The platform drivers are responsible for instantiating the counters in the stats directory if applicable. i2c_adapter_create_stats_folder is placed in i2c-core-base.c for fixing a build error on arc700. Signed-off-by: Sui Chen <suichen@xxxxxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> --- drivers/i2c/i2c-core-base.c | 23 +++++++ drivers/i2c/i2c-dev.c | 124 ++++++++++++++++++++++++++++++++++++ include/linux/i2c.h | 28 ++++++++ 3 files changed, 175 insertions(+) diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c index 84f12bf90644a..64dd79d32a0c3 100644 --- a/drivers/i2c/i2c-core-base.c +++ b/drivers/i2c/i2c-core-base.c @@ -1610,6 +1610,8 @@ static int i2c_register_adapter(struct i2c_adapter *adap) bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); mutex_unlock(&core_lock); + i2c_adapter_create_stats_directory(adap); + return 0; out_reg: @@ -2617,6 +2619,27 @@ void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred) kfree(buf); } + +/** + * 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; + + stats = kzalloc(sizeof(*stats), GFP_KERNEL); + if (!stats) { + adapter->stats = NULL; + return 1; + } + adapter->stats = stats; + adapter->stats->kobj = kobject_create_and_add("stats", &adapter->dev.kobj); + return 0; +} + EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf); MODULE_AUTHOR("Simon G. Vogl <simon@xxxxxxxxxxxxxxxxx>"); diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c index 77f576e516522..902a964d47b10 100644 --- a/drivers/i2c/i2c-dev.c +++ b/drivers/i2c/i2c-dev.c @@ -767,6 +767,130 @@ 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); +} + +static ssize_t ber_cnt_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *ber_cnt = kobj_to_adapter(pdev)->stats->ber_cnt; + + if (!ber_cnt) + return 0; + return sysfs_emit(buf, "%llu\n", *ber_cnt); +} +DEVICE_ATTR_RO(ber_cnt); + +ssize_t nack_cnt_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *nack_cnt = kobj_to_adapter(pdev)->stats->nack_cnt; + + if (!nack_cnt) + return 0; + return sysfs_emit(buf, "%llu\n", *nack_cnt); +} +DEVICE_ATTR_RO(nack_cnt); + +ssize_t rec_succ_cnt_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *rec_succ_cnt = kobj_to_adapter(pdev)->stats->rec_succ_cnt; + + if (!rec_succ_cnt) + return 0; + return sysfs_emit(buf, "%llu\n", *rec_succ_cnt); +} +DEVICE_ATTR_RO(rec_succ_cnt); + +ssize_t rec_fail_cnt_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *rec_fail_cnt = kobj_to_adapter(pdev)->stats->rec_fail_cnt; + + if (!rec_fail_cnt) + return 0; + return sysfs_emit(buf, "%llu\n", *rec_fail_cnt); +} +DEVICE_ATTR_RO(rec_fail_cnt); + +ssize_t timeout_cnt_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *timeout_cnt = kobj_to_adapter(pdev)->stats->timeout_cnt; + + if (!timeout_cnt) + return 0; + return sysfs_emit(buf, "%llu\n", *timeout_cnt); +} +DEVICE_ATTR_RO(timeout_cnt); + +ssize_t i2c_speed_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *i2c_speed = kobj_to_adapter(pdev)->stats->i2c_speed; + + if (!i2c_speed) + return 0; + return sysfs_emit(buf, "%llu\n", *i2c_speed); +} +DEVICE_ATTR_RO(i2c_speed); + +ssize_t tx_complete_cnt_show(struct device *pdev, + struct device_attribute *attr, char *buf) +{ + u64 *tx_complete_cnt = kobj_to_adapter(pdev)->stats->tx_complete_cnt; + + if (!tx_complete_cnt) + return 0; + return sysfs_emit(buf, "%llu\n", *tx_complete_cnt); +} +DEVICE_ATTR_RO(tx_complete_cnt); + +void i2c_adapter_stats_register_counter(struct i2c_adapter *adapter, + const char *counter_name, void *data_source) +{ + int ret = 1; + + if (!adapter->stats) { + if (i2c_adapter_create_stats_directory(adapter)) + return; + } + + if (!strcmp(counter_name, "ber_cnt")) { + adapter->stats->ber_cnt = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_ber_cnt.attr); + } else if (!strcmp(counter_name, "nack_cnt")) { + adapter->stats->nack_cnt = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_nack_cnt.attr); + } else if (!strcmp(counter_name, "rec_succ_cnt")) { + adapter->stats->rec_succ_cnt = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_rec_succ_cnt.attr); + } else if (!strcmp(counter_name, "rec_fail_cnt")) { + adapter->stats->rec_fail_cnt = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_rec_fail_cnt.attr); + } else if (!strcmp(counter_name, "timeout_cnt")) { + adapter->stats->timeout_cnt = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_timeout_cnt.attr); + } else if (!strcmp(counter_name, "i2c_speed")) { + adapter->stats->i2c_speed = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_i2c_speed.attr); + } else if (!strcmp(counter_name, "tx_complete_cnt")) { + adapter->stats->tx_complete_cnt = data_source; + ret = sysfs_create_file(adapter->stats->kobj, &dev_attr_tx_complete_cnt.attr); + } + + if (ret) + dev_warn(&adapter->dev, "Failed to create sysfs file for %s\n", counter_name); +} + MODULE_AUTHOR("Frodo Looijaard <frodol@xxxxxx>"); MODULE_AUTHOR("Simon G. Vogl <simon@xxxxxxxxxxxxxxxxx>"); MODULE_DESCRIPTION("I2C /dev entries driver"); diff --git a/include/linux/i2c.h b/include/linux/i2c.h index 3eb60a2e9e618..23914600af586 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 +685,27 @@ 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; + + /* a NULL value means the counter is not available */ + u64 *tx_complete_cnt; + u64 *ber_cnt; + u64 *nack_cnt; + u64 *rec_succ_cnt; + u64 *rec_fail_cnt; + u64 *timeout_cnt; + u64 *i2c_speed; +}; + /* 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 +757,18 @@ 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); -- 2.34.1.307.g9b7440fafd-goog