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Tue, 13 Apr 2021 07:59:03 -0700 (PDT) Sender: Guenter Roeck Subject: Re: [PATCH v4] hwmon: Add driver for fsp-3y PSUs and PDUs To: =?UTF-8?B?VsOhY2xhdiBLdWJlcm7DoXQ=?= Cc: Jean Delvare , Jonathan Corbet , linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210329143833.1047539-1-kubernat@cesnet.cz> <20210413104233.1857736-1-kubernat@cesnet.cz> From: Guenter Roeck Autocrypt: addr=linux@roeck-us.net; keydata= xsFNBE6H1WcBEACu6jIcw5kZ5dGeJ7E7B2uweQR/4FGxH10/H1O1+ApmcQ9i87XdZQiB9cpN RYHA7RCEK2dh6dDccykQk3bC90xXMPg+O3R+C/SkwcnUak1UZaeK/SwQbq/t0tkMzYDRxfJ7 nyFiKxUehbNF3r9qlJgPqONwX5vJy4/GvDHdddSCxV41P/ejsZ8PykxyJs98UWhF54tGRWFl 7i1xvaDB9lN5WTLRKSO7wICuLiSz5WZHXMkyF4d+/O5ll7yz/o/JxK5vO/sduYDIlFTvBZDh gzaEtNf5tQjsjG4io8E0Yq0ViobLkS2RTNZT8ICq/Jmvl0SpbHRvYwa2DhNsK0YjHFQBB0FX IdhdUEzNefcNcYvqigJpdICoP2e4yJSyflHFO4dr0OrdnGLe1Zi/8Xo/2+M1dSSEt196rXaC kwu2KgIgmkRBb3cp2vIBBIIowU8W3qC1+w+RdMUrZxKGWJ3juwcgveJlzMpMZNyM1jobSXZ0 VHGMNJ3MwXlrEFPXaYJgibcg6brM6wGfX/LBvc/haWw4yO24lT5eitm4UBdIy9pKkKmHHh7s jfZJkB5fWKVdoCv/omy6UyH6ykLOPFugl+hVL2Prf8xrXuZe1CMS7ID9Lc8FaL1ROIN/W8Vk BIsJMaWOhks//7d92Uf3EArDlDShwR2+D+AMon8NULuLBHiEUQARAQABzTJHdWVudGVyIFJv ZWNrIChMaW51eCBhY2NvdW50KSA8bGludXhAcm9lY2stdXMubmV0PsLBgQQTAQIAKwIbAwYL CQgHAwIGFQgCCQoLBBYCAwECHgECF4ACGQEFAlVcphcFCRmg06EACgkQyx8mb86fmYFg0RAA nzXJzuPkLJaOmSIzPAqqnutACchT/meCOgMEpS5oLf6xn5ySZkl23OxuhpMZTVX+49c9pvBx hpvl5bCWFu5qC1jC2eWRYU+aZZE4sxMaAGeWenQJsiG9lP8wkfCJP3ockNu0ZXXAXwIbY1O1 c+l11zQkZw89zNgWgKobKzrDMBFOYtAh0pAInZ9TSn7oA4Ctejouo5wUugmk8MrDtUVXmEA9 7f9fgKYSwl/H7dfKKsS1bDOpyJlqhEAH94BHJdK/b1tzwJCFAXFhMlmlbYEk8kWjcxQgDWMu GAthQzSuAyhqyZwFcOlMCNbAcTSQawSo3B9yM9mHJne5RrAbVz4TWLnEaX8gA5xK3uCNCeyI sqYuzA4OzcMwnnTASvzsGZoYHTFP3DQwf2nzxD6yBGCfwNGIYfS0i8YN8XcBgEcDFMWpOQhT Pu3HeztMnF3HXrc0t7e5rDW9zCh3k2PA6D2NV4fews9KDFhLlTfCVzf0PS1dRVVWM+4jVl6l HRIAgWp+2/f8dx5vPc4Ycp4IsZN0l1h9uT7qm1KTwz+sSl1zOqKD/BpfGNZfLRRxrXthvvY8 BltcuZ4+PGFTcRkMytUbMDFMF9Cjd2W9dXD35PEtvj8wnEyzIos8bbgtLrGTv/SYhmPpahJA l8hPhYvmAvpOmusUUyB30StsHIU2LLccUPPOwU0ETofVZwEQALlLbQeBDTDbwQYrj0gbx3bq 7kpKABxN2MqeuqGr02DpS9883d/t7ontxasXoEz2GTioevvRmllJlPQERVxM8gQoNg22twF7 pB/zsrIjxkE9heE4wYfN1AyzT+AxgYN6f8hVQ7Nrc9XgZZe+8IkuW/Nf64KzNJXnSH4u6nJM J2+Dt274YoFcXR1nG76Q259mKwzbCukKbd6piL+VsT/qBrLhZe9Ivbjq5WMdkQKnP7gYKCAi pNVJC4enWfivZsYupMd9qn7Uv/oCZDYoBTdMSBUblaLMwlcjnPpOYK5rfHvC4opxl+P/Vzyz 6WC2TLkPtKvYvXmdsI6rnEI4Uucg0Au/Ulg7aqqKhzGPIbVaL+U0Wk82nz6hz+WP2ggTrY1w ZlPlRt8WM9w6WfLf2j+PuGklj37m+KvaOEfLsF1v464dSpy1tQVHhhp8LFTxh/6RWkRIR2uF I4v3Xu/k5D0LhaZHpQ4C+xKsQxpTGuYh2tnRaRL14YMW1dlI3HfeB2gj7Yc8XdHh9vkpPyuT nY/ZsFbnvBtiw7GchKKri2gDhRb2QNNDyBnQn5mRFw7CyuFclAksOdV/sdpQnYlYcRQWOUGY HhQ5eqTRZjm9z+qQe/T0HQpmiPTqQcIaG/edgKVTUjITfA7AJMKLQHgp04Vylb+G6jocnQQX JqvvP09whbqrABEBAAHCwWUEGAECAA8CGwwFAlVcpi8FCRmg08MACgkQyx8mb86fmYHNRQ/+ J0OZsBYP4leJvQF8lx9zif+v4ZY/6C9tTcUv/KNAE5leyrD4IKbnV4PnbrVhjq861it/zRQW cFpWQszZyWRwNPWUUz7ejmm9lAwPbr8xWT4qMSA43VKQ7ZCeTQJ4TC8kjqtcbw41SjkjrcTG wF52zFO4bOWyovVAPncvV9eGA/vtnd3xEZXQiSt91kBSqK28yjxAqK/c3G6i7IX2rg6pzgqh hiH3/1qM2M/LSuqAv0Rwrt/k+pZXE+B4Ud42hwmMr0TfhNxG+X7YKvjKC+SjPjqp0CaztQ0H nsDLSLElVROxCd9m8CAUuHplgmR3seYCOrT4jriMFBtKNPtj2EE4DNV4s7k0Zy+6iRQ8G8ng QjsSqYJx8iAR8JRB7Gm2rQOMv8lSRdjva++GT0VLXtHULdlzg8VjDnFZ3lfz5PWEOeIMk7Rj trjv82EZtrhLuLjHRCaG50OOm0hwPSk1J64R8O3HjSLdertmw7eyAYOo4RuWJguYMg5DRnBk WkRwrSuCn7UG+qVWZeKEsFKFOkynOs3pVbcbq1pxbhk3TRWCGRU5JolI4ohy/7JV1TVbjiDI HP/aVnm6NC8of26P40Pg8EdAhajZnHHjA7FrJXsy3cyIGqvg9os4rNkUWmrCfLLsZDHD8FnU mDW4+i+XlNFUPUYMrIKi9joBhu18ssf5i5Q= Message-ID: <43c5cc02-d2ad-ceee-7709-190681b81ae7@roeck-us.net> Date: Tue, 13 Apr 2021 07:59:02 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210413104233.1857736-1-kubernat@cesnet.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/13/21 3:42 AM, Václav Kubernát wrote: > This patch adds support for these devices: > - YH-5151E - the PDU > - YM-2151E - the PSU > > The device datasheet says that the devices support PMBus 1.2, but in my > testing, a lot of the commands aren't supported and if they are, they > sometimes behave strangely or inconsistently. For example, writes to the > PAGE command requires using PEC, otherwise the write won't work and the > page won't switch, even though, the standard says that PEC is opiotnal. optional > On the other hand, writes the SMBALERT don't require PEC. Because of s/writes the/writes to/ ? > this, the driver is mostly reverse engineered with the help of a tool > called pmbus_peek written by David Brownell (and later adopted by my > colleague Jan Kundrát). > > The device also has some sort of a timing issue when switching pages, > which is explained further in the code. > > Because of this, the driver support is limited. It exposes only the > values, that have been tested to work correctly. > You might want to add those details into the driver code, below the copyright line. It would be more valuable there than in the commit log. > Signed-off-by: Václav Kubernát > --- > Documentation/hwmon/fsp-3y.rst | 26 ++++ Needs to be added to index.rst. > drivers/hwmon/pmbus/Kconfig | 10 ++ > drivers/hwmon/pmbus/Makefile | 1 + > drivers/hwmon/pmbus/fsp-3y.c | 239 +++++++++++++++++++++++++++++++++ > 4 files changed, 276 insertions(+) > create mode 100644 Documentation/hwmon/fsp-3y.rst > create mode 100644 drivers/hwmon/pmbus/fsp-3y.c > > diff --git a/Documentation/hwmon/fsp-3y.rst b/Documentation/hwmon/fsp-3y.rst > new file mode 100644 > index 000000000000..68a547021846 > --- /dev/null > +++ b/Documentation/hwmon/fsp-3y.rst > @@ -0,0 +1,26 @@ > +Kernel driver fsp3y > +====================== > +Supported devices: > + * 3Y POWER YH-5151E > + * 3Y POWER YM-2151E > + > +Author: Václav Kubernát > + > +Description > +----------- > +This driver implements limited support for two 3Y POWER devices. > + > +Sysfs entries > +------------- > +in1_input input voltage > +in2_input 12V output voltage > +in3_input 5V output voltage > +curr1_input input current > +curr2_input 12V output current > +curr3_input 5V output current > +fan1_input fan rpm > +temp1_input temperature 1 > +temp2_input temperature 2 > +temp3_input temperature 3 > +power1_input input power > +power2_input output power > diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig > index 03606d4298a4..9d12d446396c 100644 > --- a/drivers/hwmon/pmbus/Kconfig > +++ b/drivers/hwmon/pmbus/Kconfig > @@ -56,6 +56,16 @@ config SENSORS_BEL_PFE > This driver can also be built as a module. If so, the module will > be called bel-pfe. > > +config SENSORS_FSP_3Y > + tristate "FSP/3Y-Power power supplies" > + help > + If you say yes here you get hardware monitoring support for > + FSP/3Y-Power hot-swap power supplies. > + Supported models: YH-5151E, YM-2151E > + > + This driver can also be built as a module. If so, the module will > + be called fsp-3y. > + > config SENSORS_IBM_CFFPS > tristate "IBM Common Form Factor Power Supply" > depends on LEDS_CLASS > diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile > index 6a4ba0fdc1db..bfe218ad898f 100644 > --- a/drivers/hwmon/pmbus/Makefile > +++ b/drivers/hwmon/pmbus/Makefile > @@ -8,6 +8,7 @@ obj-$(CONFIG_SENSORS_PMBUS) += pmbus.o > obj-$(CONFIG_SENSORS_ADM1266) += adm1266.o > obj-$(CONFIG_SENSORS_ADM1275) += adm1275.o > obj-$(CONFIG_SENSORS_BEL_PFE) += bel-pfe.o > +obj-$(CONFIG_SENSORS_FSP_3Y) += fsp-3y.o > obj-$(CONFIG_SENSORS_IBM_CFFPS) += ibm-cffps.o > obj-$(CONFIG_SENSORS_INSPUR_IPSPS) += inspur-ipsps.o > obj-$(CONFIG_SENSORS_IR35221) += ir35221.o > diff --git a/drivers/hwmon/pmbus/fsp-3y.c b/drivers/hwmon/pmbus/fsp-3y.c > new file mode 100644 > index 000000000000..2185ab119fd2 > --- /dev/null > +++ b/drivers/hwmon/pmbus/fsp-3y.c > @@ -0,0 +1,239 @@ > +// SPDX-License-Identifier: GPL-2.0-or-later > +/* > + * Hardware monitoring driver for FSP 3Y-Power PSUs > + * > + * Copyright (c) 2021 Václav Kubernát, CESNET > + */ > + > +#include > +#include > +#include > +#include > +#include "pmbus.h" > + > +#define YM2151_PAGE_12V_LOG 0x00 > +#define YM2151_PAGE_12V_REAL 0x00 > +#define YM2151_PAGE_5VSB_LOG 0x01 > +#define YM2151_PAGE_5VSB_REAL 0x20 > +#define YH5151E_PAGE_12V_LOG 0x00 > +#define YH5151E_PAGE_12V_REAL 0x00 > +#define YH5151E_PAGE_5V_LOG 0x01 > +#define YH5151E_PAGE_5V_REAL 0x10 > +#define YH5151E_PAGE_3V3_LOG 0x02 > +#define YH5151E_PAGE_3V3_REAL 0x11 > + > +enum chips { > + ym2151e, > + yh5151e > +}; > + > +struct fsp3y_data { > + struct pmbus_driver_info info; > + int chip; > + int page; > +}; > + > +#define to_fsp3y_data(x) container_of(x, struct fsp3y_data, info) > + > +static int page_log_to_page_real(int page_log, enum chips chip) > +{ > + switch (chip) { > + case ym2151e: > + switch (page_log) { > + case YM2151_PAGE_12V_LOG: > + return YM2151_PAGE_12V_REAL; > + case YM2151_PAGE_5VSB_LOG: > + return YM2151_PAGE_5VSB_REAL; > + } > + return -EINVAL; > + case yh5151e: > + switch (page_log) { > + case YH5151E_PAGE_12V_LOG: > + return YH5151E_PAGE_12V_REAL; > + case YH5151E_PAGE_5V_LOG: > + return YH5151E_PAGE_5V_LOG; > + case YH5151E_PAGE_3V3_LOG: > + return YH5151E_PAGE_3V3_REAL; > + } > + return -EINVAL; > + } > + > + return -EINVAL; > +} > + > +static int set_page(struct i2c_client *client, int page_log) > +{ > + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); > + struct fsp3y_data *data = to_fsp3y_data(info); > + int rv; > + int page_real; > + > + if (page_log < 0) > + return 0; > + > + page_real = page_log_to_page_real(page_log, data->chip); > + if (page_real < 0) > + return page_real; > + > + if (data->page != page_real) { > + rv = i2c_smbus_write_byte_data(client, PMBUS_PAGE, page_real); > + if (rv < 0) > + return rv; > + > + data->page = page_real; > + > + /* Testing showed that the device has a timing issue. After Somehow network subsystem multi-line alignments slipped in. Not in hwmon, please. I cringe at those; it makes my brain focus on the comment (because it is asynchronous) instead of the code. > + * setting a page, it takes a while, before the device actually > + * gives the correct values from the correct page. 20 ms was > + * tested to be enough to not give wrong values (15 ms wasn't > + * enough) > + */ > + usleep_range(20000, 30000); > + } > + > + return 0; > +} > + > +static int fsp3y_read_byte_data(struct i2c_client *client, int page, int reg) > +{ > + int rv; > + > + rv = set_page(client, page); > + if (rv < 0) > + return rv; > + > + return i2c_smbus_read_byte_data(client, reg); > +} > + > +static int fsp3y_read_word_data(struct i2c_client *client, int page, int phase, int reg) > +{ > + int rv; > + > + /* This masks commands which weren't tested to work correctly. Some of the masked commands > + * return either 0xFFFF. These would probably get tagged as invalid by pmbus_core. Other s/either// ? > + * ones do return values, which might be useful (that is, they are not 0xFFFF), but their s/values,/values/ > + * encoding is unknown, and so they are unsupported. > + */ > + switch (reg) { > + case PMBUS_READ_FAN_SPEED_1: > + case PMBUS_READ_IIN: > + case PMBUS_READ_IOUT: > + case PMBUS_READ_PIN: > + case PMBUS_READ_POUT: > + case PMBUS_READ_TEMPERATURE_1: > + case PMBUS_READ_TEMPERATURE_2: > + case PMBUS_READ_TEMPERATURE_3: > + case PMBUS_READ_VIN: > + case PMBUS_READ_VOUT: > + case PMBUS_STATUS_WORD: > + break; > + default: > + return -ENXIO; > + } > + > + rv = set_page(client, page); > + if (rv < 0) > + return rv; > + > + return i2c_smbus_read_word_data(client, reg); > +} > + > +struct pmbus_driver_info fsp3y_info[] = { > + [ym2151e] = { > + .pages = 2, > + .func[YM2151_PAGE_12V_LOG] = > + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | > + PMBUS_HAVE_PIN | PMBUS_HAVE_POUT | > + PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | > + PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | > + PMBUS_HAVE_FAN12, > + .func[YM2151_PAGE_5VSB_LOG] = > + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT, > + PMBUS_HAVE_IIN, > + .read_word_data = fsp3y_read_word_data, > + .read_byte_data = fsp3y_read_byte_data, > + }, > + [yh5151e] = { > + .pages = 3, > + .func[YH5151E_PAGE_12V_LOG] = > + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | > + PMBUS_HAVE_POUT | > + PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3, > + .func[YH5151E_PAGE_5V_LOG] = > + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | > + PMBUS_HAVE_POUT, > + .func[YH5151E_PAGE_3V3_LOG] = > + PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | > + PMBUS_HAVE_POUT, > + .read_word_data = fsp3y_read_word_data, > + .read_byte_data = fsp3y_read_byte_data, > + } > +}; > + > +static int fsp3y_detect(struct i2c_client *client) > +{ > + int rv; > + u8 buf[I2C_SMBUS_BLOCK_MAX]; > + > + rv = i2c_smbus_read_block_data(client, PMBUS_MFR_MODEL, buf); > + if (rv < 0) > + return rv; > + > + if (rv == 8 && !strncmp(buf, "YM-2151E", strlen("YM-2151E"))) > + return ym2151e; > + else if (rv == 8 && !strncmp(buf, "YH-5151E", strlen("YH-5151E"))) > + return yh5151e; better if (rv == 8) { /* rest of check */ } > + > + dev_err(&client->dev, "Unsupported model %.*s\n", rv, buf); Sorry I didn't notice before. This assumes that the buffer is zero-terminated, which may not be the case. For this to work, add another byte to the buffer (u8 buf[I2C_SMBUS_BLOCK_MAX + 1];), and add buf[rv] = '\0'; You could actually do that before checking the returned strings and then just use strcmp() for the model comparisons, without bothering about the return length. > + return -ENODEV; > +} > + > +static const struct i2c_device_id fsp3y_id[] = { > + {"ym2151e", ym2151e}, > + {"yh5151e", yh5151e} > +}; > + > +static int fsp3y_probe(struct i2c_client *client) > +{ > + struct fsp3y_data *data; > + const struct i2c_device_id *id; > + int rv; > + > + data = devm_kzalloc(&client->dev, sizeof(struct fsp3y_data), GFP_KERNEL); > + if (!data) > + return -ENOMEM; > + > + data->chip = fsp3y_detect(client); > + if (data->chip < 0) > + return data->chip; > + > + id = i2c_match_id(fsp3y_id, client); > + if (data->chip != id->driver_data) > + dev_warn(&client->dev, "Device mismatch: Configured %s (%d), detected %d\n", id->name, (int)id->driver_data, data->chip); > + > + rv = i2c_smbus_read_byte_data(client, PMBUS_PAGE); > + if (rv < 0) > + return rv; > + data->page = rv; > + > + data->info = fsp3y_info[data->chip]; > + > + return pmbus_do_probe(client, &data->info); > +} > + > +MODULE_DEVICE_TABLE(i2c, pmbus_id); > + > +/* This is the driver that will be inserted */ Nit: Useless comment > +static struct i2c_driver fsp3y_driver = { > + .driver = { > + .name = "fsp3y", > + }, > + .probe_new = fsp3y_probe, > + .id_table = fsp3y_id > +}; > + > +module_i2c_driver(fsp3y_driver); > + > +MODULE_AUTHOR("Václav Kubernát"); > +MODULE_DESCRIPTION("PMBus driver for FSP/3Y-Power power supplies"); > +MODULE_LICENSE("GPL"); >