From 1e4063329fe865380177945efed3a42c0bbbfa05 Mon Sep 17 00:00:00 2001 From: Erik Rosen Date: Mon, 19 Apr 2021 12:12:51 +0200 Subject: [PATCH] hwmon: (pmbus) Add pmbus driver for MAX15301 Add pmbus driver support for Maxim MAX15301 InTune Automatically Compensated Digital PoL Controller with Driver and PMBus Telemetry Even though the specification does not specifically mention it, extensive empirical testing has revealed that auto-detection of limit-registers will fail in a random fashion unless the delay parameter is set to above about 80us. The default delay is set to 100us to include some safety margin. This patch is tested on a Flex BMR461 converter module. Signed-off-by: Erik Rosen Link: https://lore.kernel.org/r/20210419101251.24840-1-erik.rosen@metormote.com [groeck: Added rationale for delay to driver header] Signed-off-by: Guenter Roeck --- Documentation/hwmon/index.rst | 1 + Documentation/hwmon/max15301.rst | 87 ++++++++++++++ MAINTAINERS | 7 ++ drivers/hwmon/pmbus/Kconfig | 9 ++ drivers/hwmon/pmbus/Makefile | 1 + drivers/hwmon/pmbus/max15301.c | 189 +++++++++++++++++++++++++++++++ 6 files changed, 294 insertions(+) create mode 100644 Documentation/hwmon/max15301.rst create mode 100644 drivers/hwmon/pmbus/max15301.c diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst index d6a050f85477..6bc696fa0ed5 100644 --- a/Documentation/hwmon/index.rst +++ b/Documentation/hwmon/index.rst @@ -115,6 +115,7 @@ Hardware Monitoring Kernel Drivers ltc4260 ltc4261 max127 + max15301 max16064 max16065 max1619 diff --git a/Documentation/hwmon/max15301.rst b/Documentation/hwmon/max15301.rst new file mode 100644 index 000000000000..e3dc22fe1c6d --- /dev/null +++ b/Documentation/hwmon/max15301.rst @@ -0,0 +1,87 @@ +.. SPDX-License-Identifier: GPL-2.0 + +Kernel driver max15301 +====================== + +Supported chips: + + * Maxim MAX15301 + + Prefix: 'max15301', 'bmr461' + + Addresses scanned: - + + Datasheet: https://datasheets.maximintegrated.com/en/ds/MAX15301.pdf + +Author: Erik Rosen + + +Description +----------- + +This driver supports hardware monitoring for Maxim MAX15301 controller chip and +compatible modules. + +The driver is a client driver to the core PMBus driver. Please see +Documentation/hwmon/pmbus.rst and Documentation.hwmon/pmbus-core for details +on PMBus client drivers. + + +Usage Notes +----------- + +This driver does not auto-detect devices. You will have to instantiate the +devices explicitly. Please see Documentation/i2c/instantiating-devices.rst for +details. + + +Platform data support +--------------------- + +The driver supports standard PMBus driver platform data. + + +Module parameters +----------------- + +delay +----- + +The controller requires a minimum interval between I2C bus accesses. +The default interval is set to 100 us. For manual override, the driver +provides a writeable module parameter, 'delay', which can be used to +set the interval to a value between 0 and 65,535 microseconds. + + +Sysfs entries +------------- + +The following attributes are supported. Limits are read-write; all other +attributes are read-only. + +======================= ======================================================== +in1_label "vin" +in1_input Measured input voltage. +in1_lcrit Critical minimum input voltage. +in1_crit Critical maximum input voltage. +in1_lcrit_alarm Input voltage critical low alarm. +in1_crit_alarm Input voltage critical high alarm. + +in2_label "vout1" +in2_input Measured output voltage. +in2_lcrit Critical minimum output Voltage. +in2_crit Critical maximum output voltage. +in2_lcrit_alarm Critical output voltage critical low alarm. +in2_crit_alarm Critical output voltage critical high alarm. + +curr1_label "iout1" +curr1_input Measured output current. +curr1_crit Critical maximum output current. +curr1_crit_alarm Output current critical high alarm. + +temp1_input Measured maximum temperature of all phases. +temp1_max Maximum temperature limit. +temp1_max_alarm High temperature alarm. +temp1_crit Critical maximum temperature limit. +temp1_crit_alarm Critical maximum temperature alarm. +======================= ======================================================== diff --git a/MAINTAINERS b/MAINTAINERS index bb5bbaa5fba2..8f4010d6031c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -10791,6 +10791,13 @@ S: Orphan F: drivers/video/fbdev/matrox/matroxfb_* F: include/uapi/linux/matroxfb.h +MAX15301 DRIVER +M: Daniel Nilsson +L: linux-hwmon@vger.kernel.org +S: Maintained +F: Documentation/hwmon/max15301.rst +F: drivers/hwmon/pmbus/max15301.c + MAX16065 HARDWARE MONITOR DRIVER M: Guenter Roeck L: linux-hwmon@vger.kernel.org diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig index e9727176b167..37a5c39784fa 100644 --- a/drivers/hwmon/pmbus/Kconfig +++ b/drivers/hwmon/pmbus/Kconfig @@ -176,6 +176,15 @@ config SENSORS_LTC3815 This driver can also be built as a module. If so, the module will be called ltc3815. +config SENSORS_MAX15301 + tristate "Maxim MAX15301" + help + If you say yes here you get hardware monitoring support for Maxim + MAX15301, as well as for Flex BMR461. + + This driver can also be built as a module. If so, the module will + be called max15301. + config SENSORS_MAX16064 tristate "Maxim MAX16064" help diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile index 4ca98e9005f1..f8dcc27cd56a 100644 --- a/drivers/hwmon/pmbus/Makefile +++ b/drivers/hwmon/pmbus/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_SENSORS_ISL68137) += isl68137.o obj-$(CONFIG_SENSORS_LM25066) += lm25066.o obj-$(CONFIG_SENSORS_LTC2978) += ltc2978.o obj-$(CONFIG_SENSORS_LTC3815) += ltc3815.o +obj-$(CONFIG_SENSORS_MAX15301) += max15301.o obj-$(CONFIG_SENSORS_MAX16064) += max16064.o obj-$(CONFIG_SENSORS_MAX16601) += max16601.o obj-$(CONFIG_SENSORS_MAX20730) += max20730.o diff --git a/drivers/hwmon/pmbus/max15301.c b/drivers/hwmon/pmbus/max15301.c new file mode 100644 index 000000000000..727455e5740b --- /dev/null +++ b/drivers/hwmon/pmbus/max15301.c @@ -0,0 +1,189 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Hardware monitoring driver for Maxim MAX15301 + * + * Copyright (c) 2021 Flextronics International Sweden AB + * + * Even though the specification does not specifically mention it, + * extensive empirical testing has revealed that auto-detection of + * limit-registers will fail in a random fashion unless the delay + * parameter is set to above about 80us. The default delay is set + * to 100us to include some safety margin. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include "pmbus.h" + +static const struct i2c_device_id max15301_id[] = { + {"bmr461", 0}, + {"max15301", 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, max15301_id); + +struct max15301_data { + int id; + ktime_t access; /* Chip access time */ + int delay; /* Delay between chip accesses in us */ + struct pmbus_driver_info info; +}; + +#define to_max15301_data(x) container_of(x, struct max15301_data, info) + +#define MAX15301_WAIT_TIME 100 /* us */ + +static ushort delay = MAX15301_WAIT_TIME; +module_param(delay, ushort, 0644); +MODULE_PARM_DESC(delay, "Delay between chip accesses in us"); + +static struct max15301_data max15301_data = { + .info = { + .pages = 1, + .func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT + | PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT + | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 + | PMBUS_HAVE_STATUS_TEMP + | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT, + } +}; + +/* This chip needs a delay between accesses */ +static inline void max15301_wait(const struct max15301_data *data) +{ + if (data->delay) { + s64 delta = ktime_us_delta(ktime_get(), data->access); + + if (delta < data->delay) + udelay(data->delay - delta); + } +} + +static int max15301_read_word_data(struct i2c_client *client, int page, + int phase, int reg) +{ + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); + struct max15301_data *data = to_max15301_data(info); + int ret; + + if (page > 0) + return -ENXIO; + + if (reg >= PMBUS_VIRT_BASE) + return -ENXIO; + + max15301_wait(data); + ret = pmbus_read_word_data(client, page, phase, reg); + data->access = ktime_get(); + + return ret; +} + +static int max15301_read_byte_data(struct i2c_client *client, int page, int reg) +{ + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); + struct max15301_data *data = to_max15301_data(info); + int ret; + + if (page > 0) + return -ENXIO; + + max15301_wait(data); + ret = pmbus_read_byte_data(client, page, reg); + data->access = ktime_get(); + + return ret; +} + +static int max15301_write_word_data(struct i2c_client *client, int page, int reg, + u16 word) +{ + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); + struct max15301_data *data = to_max15301_data(info); + int ret; + + if (page > 0) + return -ENXIO; + + if (reg >= PMBUS_VIRT_BASE) + return -ENXIO; + + max15301_wait(data); + ret = pmbus_write_word_data(client, page, reg, word); + data->access = ktime_get(); + + return ret; +} + +static int max15301_write_byte(struct i2c_client *client, int page, u8 value) +{ + const struct pmbus_driver_info *info = pmbus_get_driver_info(client); + struct max15301_data *data = to_max15301_data(info); + int ret; + + if (page > 0) + return -ENXIO; + + max15301_wait(data); + ret = pmbus_write_byte(client, page, value); + data->access = ktime_get(); + + return ret; +} + +static int max15301_probe(struct i2c_client *client) +{ + int status; + u8 device_id[I2C_SMBUS_BLOCK_MAX + 1]; + const struct i2c_device_id *mid; + struct pmbus_driver_info *info = &max15301_data.info; + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_BYTE_DATA + | I2C_FUNC_SMBUS_BLOCK_DATA)) + return -ENODEV; + + status = i2c_smbus_read_block_data(client, PMBUS_IC_DEVICE_ID, device_id); + if (status < 0) { + dev_err(&client->dev, "Failed to read Device Id\n"); + return status; + } + for (mid = max15301_id; mid->name[0]; mid++) { + if (!strncasecmp(mid->name, device_id, strlen(mid->name))) + break; + } + if (!mid->name[0]) { + dev_err(&client->dev, "Unsupported device\n"); + return -ENODEV; + } + + max15301_data.delay = delay; + + info->read_byte_data = max15301_read_byte_data; + info->read_word_data = max15301_read_word_data; + info->write_byte = max15301_write_byte; + info->write_word_data = max15301_write_word_data; + + return pmbus_do_probe(client, info); +} + +static struct i2c_driver max15301_driver = { + .driver = { + .name = "max15301", + }, + .probe_new = max15301_probe, + .id_table = max15301_id, +}; + +module_i2c_driver(max15301_driver); + +MODULE_AUTHOR("Erik Rosen "); +MODULE_DESCRIPTION("PMBus driver for Maxim MAX15301"); +MODULE_LICENSE("GPL");