From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753241AbdHNQpv (ORCPT ); Mon, 14 Aug 2017 12:45:51 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:39669 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751520AbdHNQpa (ORCPT ); Mon, 14 Aug 2017 12:45:30 -0400 Subject: Re: [PATCH v3] hwmon: (pmbus): Add debugfs for status registers To: Guenter Roeck Cc: jdelvare@suse.com, linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, joel@jms.id.au, "Edward A. James" References: <1502722790-12704-1-git-send-email-eajames@linux.vnet.ibm.com> <20170814161358.GE7025@roeck-us.net> From: Eddie James Date: Mon, 14 Aug 2017 11:45:23 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.0 MIME-Version: 1.0 In-Reply-To: <20170814161358.GE7025@roeck-us.net> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-TM-AS-GCONF: 00 x-cbid: 17081416-0008-0000-0000-000008655CE7 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007544; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000220; SDB=6.00902259; UDB=6.00451875; IPR=6.00682475; BA=6.00005531; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00016690; XFM=3.00000015; UTC=2017-08-14 16:45:27 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17081416-0009-0000-0000-000043892895 Message-Id: <32f8c672-41cb-b7d1-2660-a90a9b0c167f@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-08-14_15:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=2 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1706020000 definitions=main-1708140274 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/14/2017 11:13 AM, Guenter Roeck wrote: > On Mon, Aug 14, 2017 at 09:59:50AM -0500, Eddie James wrote: >> From: "Edward A. James" >> >> Export all the available status registers through debugfs. This is >> useful for hardware diagnostics, especially on multi-page pmbus devices, >> as user-space access of the i2c space could corrupt the pmbus page >> accounting. >> >> Signed-off-by: Edward A. James >> >> Changes since v2: >> * Remove client driver conditional debugfs - add it for all devices. >> * Use scnprintf instead of snprintf. >> * Add module_init and module_exit to create root pmbus debugfs >> directory. >> --- >> drivers/hwmon/pmbus/pmbus_core.c | 200 +++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 200 insertions(+) >> >> diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c >> index ef135d8..677bea1 100644 >> --- a/drivers/hwmon/pmbus/pmbus_core.c >> +++ b/drivers/hwmon/pmbus/pmbus_core.c >> @@ -19,6 +19,7 @@ >> * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. >> */ >> >> +#include >> #include >> #include >> #include >> @@ -101,6 +102,7 @@ struct pmbus_data { >> int num_attributes; >> struct attribute_group group; >> const struct attribute_group *groups[2]; >> + struct dentry *debugfs; /* debugfs device directory */ >> >> struct pmbus_sensor *sensors; >> >> @@ -120,6 +122,12 @@ struct pmbus_data { >> u8 currpage; >> }; >> >> +struct pmbus_debugfs_entry { >> + struct i2c_client *client; >> + u8 page; >> + u8 reg; >> +}; >> + >> void pmbus_clear_cache(struct i2c_client *client) >> { >> struct pmbus_data *data = i2c_get_clientdata(client); >> @@ -1893,6 +1901,174 @@ static int pmbus_regulator_register(struct pmbus_data *data) >> } >> #endif >> >> +static struct dentry *pmbus_debugfs_dir; /* pmbus debugfs directory */ >> + >> +#if IS_ENABLED(CONFIG_DEBUG_FS) >> +static int pmbus_debugfs_get(void *data, u64 *val) >> +{ >> + struct pmbus_debugfs_entry *entry = data; >> + >> + *val = _pmbus_read_byte_data(entry->client, entry->page, entry->reg); >> + >> + return 0; >> +} >> +DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops, pmbus_debugfs_get, NULL, >> + "0x%02llx\n"); >> + >> +static int pmbus_debugfs_get_status(void *data, u64 *val) >> +{ >> + struct pmbus_debugfs_entry *entry = data; >> + struct pmbus_data *pdata = i2c_get_clientdata(entry->client); >> + >> + *val = pdata->read_status(entry->client, entry->page); > Wait ... read_status() returns an integer where a negative value reflects > an error. Are you sure you want to display that as 4-digit hex value ? > Wouldn't it be better to return that error instead ? Good point, thanks. Also applicable for _pmbus_read_byte_data above. On to v4... Eddie > > Guenter > >> + >> + return 0; >> +} >> +DEFINE_DEBUGFS_ATTRIBUTE(pmbus_debugfs_ops_status, pmbus_debugfs_get_status, >> + NULL, "0x%04llx\n"); >> + >> +static int pmbus_init_debugfs(struct i2c_client *client, >> + struct pmbus_data *data) >> +{ >> + int i, idx = 0; >> + char name[PMBUS_NAME_SIZE]; >> + struct pmbus_debugfs_entry *entries; >> + >> + if (!pmbus_debugfs_dir) >> + return -ENODEV; >> + >> + /* >> + * Create the debugfs directory for this device. Use the hwmon device >> + * name to avoid conflicts (hwmon numbers are globally unique). >> + */ >> + data->debugfs = debugfs_create_dir(dev_name(data->hwmon_dev), >> + pmbus_debugfs_dir); >> + if (IS_ERR_OR_NULL(data->debugfs)) { >> + data->debugfs = NULL; >> + return -ENODEV; >> + } >> + >> + /* Allocate the max possible entries we need. */ >> + entries = devm_kzalloc(data->dev, >> + sizeof(*entries) * (data->info->pages * 10), >> + GFP_KERNEL); >> + if (!entries) >> + return -ENOMEM; >> + >> + for (i = 0; i < data->info->pages; ++i) { >> + /* Check accessibility of status register if it's not page 0 */ >> + if (!i || pmbus_check_status_register(client, i)) { >> + /* No need to set reg as we have special read op. */ >> + entries[idx].client = client; >> + entries[idx].page = i; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops_status); >> + } >> + >> + if (data->info->func[i] & PMBUS_HAVE_STATUS_VOUT) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_VOUT; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_vout", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (data->info->func[i] & PMBUS_HAVE_STATUS_IOUT) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_IOUT; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_iout", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (data->info->func[i] & PMBUS_HAVE_STATUS_INPUT) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_INPUT; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_input", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (data->info->func[i] & PMBUS_HAVE_STATUS_TEMP) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_TEMPERATURE; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_temp", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (pmbus_check_byte_register(client, i, PMBUS_STATUS_CML)) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_CML; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_cml", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (pmbus_check_byte_register(client, i, PMBUS_STATUS_OTHER)) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_OTHER; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_other", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (pmbus_check_byte_register(client, i, >> + PMBUS_STATUS_MFR_SPECIFIC)) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_MFR_SPECIFIC; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_mfr", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (data->info->func[i] & PMBUS_HAVE_STATUS_FAN12) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_FAN_12; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_fan12", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + >> + if (data->info->func[i] & PMBUS_HAVE_STATUS_FAN34) { >> + entries[idx].client = client; >> + entries[idx].page = i; >> + entries[idx].reg = PMBUS_STATUS_FAN_34; >> + scnprintf(name, PMBUS_NAME_SIZE, "status%d_fan34", i); >> + debugfs_create_file(name, 0444, data->debugfs, >> + &entries[idx++], >> + &pmbus_debugfs_ops); >> + } >> + } >> + >> + return 0; >> +} >> +#else >> +static int pmbus_init_debugfs(struct i2c_client *client, >> + struct pmbus_data *data) >> +{ >> + return 0; >> +} >> +#endif /* IS_ENABLED(CONFIG_DEBUG_FS) */ >> + >> int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id, >> struct pmbus_driver_info *info) >> { >> @@ -1952,6 +2128,10 @@ int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id, >> if (ret) >> goto out_unregister; >> >> + ret = pmbus_init_debugfs(client, data); >> + if (ret) >> + dev_warn(dev, "Failed to register debugfs\n"); >> + >> return 0; >> >> out_unregister: >> @@ -1965,12 +2145,32 @@ int pmbus_do_probe(struct i2c_client *client, const struct i2c_device_id *id, >> int pmbus_do_remove(struct i2c_client *client) >> { >> struct pmbus_data *data = i2c_get_clientdata(client); >> + >> + debugfs_remove_recursive(data->debugfs); >> + >> hwmon_device_unregister(data->hwmon_dev); >> kfree(data->group.attrs); >> return 0; >> } >> EXPORT_SYMBOL_GPL(pmbus_do_remove); >> >> +static int __init pmbus_core_init(void) >> +{ >> + pmbus_debugfs_dir = debugfs_create_dir("pmbus", NULL); >> + if (IS_ERR(pmbus_debugfs_dir)) >> + pmbus_debugfs_dir = NULL; >> + >> + return 0; >> +} >> + >> +static void __exit pmbus_core_exit(void) >> +{ >> + debugfs_remove_recursive(pmbus_debugfs_dir); >> +} >> + >> +module_init(pmbus_core_init); >> +module_exit(pmbus_core_exit); >> + >> MODULE_AUTHOR("Guenter Roeck"); >> MODULE_DESCRIPTION("PMBus core driver"); >> MODULE_LICENSE("GPL"); >> -- >> 1.8.3.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html