Re: [PATCH v2 2/3] hwmon: (pmbus): Add POWER system power supply driver
From: Eddie James
Date: Fri Aug 11 2017 - 10:31:15 EST
On 08/10/2017 08:18 PM, Guenter Roeck wrote:
On Thu, Aug 10, 2017 at 05:19:45PM -0500, Eddie James wrote:
From: "Edward A. James" <eajames@xxxxxxxxxx>
Add the driver to monitor POWER system power supplies with hwmon over
pmbus.
Signed-off-by: Edward A. James <eajames@xxxxxxxxxx>
---
drivers/hwmon/pmbus/Kconfig | 10 +++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/powerps.c | 144 ++++++++++++++++++++++++++++++++++++++++++
3 files changed, 155 insertions(+)
create mode 100644 drivers/hwmon/pmbus/powerps.c
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 68d717a..8925c1a 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -125,6 +125,16 @@ config SENSORS_MAX8688
This driver can also be built as a module. If so, the module will
be called max8688.
+config SENSORS_POWERPS
+ tristate "IBM POWER System Power Supply"
+ default n
+ help
+ If you say yes here you get hardware monitoring support for the IBM
+ POWER system power supply.
+
+ This driver can also be built as a module. If so, the module will
+ be called powerps.
+
config SENSORS_TPS40422
tristate "TI TPS40422"
default n
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 75bb7ca..3303af5 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -13,6 +13,7 @@ obj-$(CONFIG_SENSORS_MAX16064) += max16064.o
obj-$(CONFIG_SENSORS_MAX20751) += max20751.o
obj-$(CONFIG_SENSORS_MAX34440) += max34440.o
obj-$(CONFIG_SENSORS_MAX8688) += max8688.o
+obj-$(CONFIG_SENSORS_POWERPS) += powerps.o
obj-$(CONFIG_SENSORS_TPS40422) += tps40422.o
obj-$(CONFIG_SENSORS_UCD9000) += ucd9000.o
obj-$(CONFIG_SENSORS_UCD9200) += ucd9200.o
diff --git a/drivers/hwmon/pmbus/powerps.c b/drivers/hwmon/pmbus/powerps.c
new file mode 100644
index 0000000..21d28f2
--- /dev/null
+++ b/drivers/hwmon/pmbus/powerps.c
@@ -0,0 +1,144 @@
+/*
+ * Copyright 2017 IBM Corp.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/i2c.h>
+#include <linux/jiffies.h>
+#include <linux/module.h>
+
+#include "pmbus.h"
+
+/* STATUS_MFR_SPECIFIC bits */
+#define POWERPS_MFR_FAN_FAULT BIT(0)
+#define POWERPS_MFR_THERMAL_FAULT BIT(1)
+#define POWERPS_MFR_OV_FAULT BIT(2)
+#define POWERPS_MFR_UV_FAULT BIT(3)
+#define POWERPS_MFR_PS_KILL BIT(4)
+#define POWERPS_MFR_OC_FAULT BIT(5)
+#define POWERPS_MFR_VAUX_FAULT BIT(6)
+#define POWERPS_MFR_CURRENT_SHARE_WARNING BIT(7)
+
+static int powerps_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+ int rc, mfr;
+
+ switch (reg) {
+ case PMBUS_STATUS_VOUT:
+ case PMBUS_STATUS_IOUT:
+ case PMBUS_STATUS_TEMPERATURE:
+ case PMBUS_STATUS_FAN_12:
+ rc = pmbus_read_byte_data(client, page, reg);
+ if (rc < 0)
+ return rc;
+
+ mfr = pmbus_read_byte_data(client, page,
+ PMBUS_STATUS_MFR_SPECIFIC);
+ if (mfr < 0)
+ return rc;
return mfr; ?
Well I returned rc because we read the status register without error, so
just return the status register contents without the additional mfr
bits. It's not very clear... I better add a comment.
+
+ /* Add MFR_SPECIFIC bits to the standard pmbus status regs. */
+ if (reg == PMBUS_STATUS_FAN_12) {
+ if (mfr & POWERPS_MFR_FAN_FAULT)
+ rc |= PB_FAN_FAN1_FAULT;
+ } else if (reg == PMBUS_STATUS_TEMPERATURE) {
+ if (mfr & POWERPS_MFR_THERMAL_FAULT)
+ rc |= PB_TEMP_OT_FAULT;
+ } else if (reg == PMBUS_STATUS_VOUT) {
+ if (mfr &
+ (POWERPS_MFR_OV_FAULT | POWERPS_MFR_VAUX_FAULT))
Wondering - this suggests that there is a VAUX. Would it make sense
to map it to PMBUS_VIRT_READ_VMON ?
There is no VAUX for this device. The power supply spec calls it "12Vaux
Fault" but I don't know why.
Thanks for the quick review!
Eddie
+ rc |= PB_VOLTAGE_OV_FAULT;
+ if (mfr & POWERPS_MFR_UV_FAULT)
+ rc |= PB_VOLTAGE_UV_FAULT;
+ } else if (reg == PMBUS_STATUS_IOUT) {
+ if (mfr & POWERPS_MFR_OC_FAULT)
+ rc |= PB_IOUT_OC_FAULT;
+ if (mfr & POWERPS_MFR_CURRENT_SHARE_WARNING)
+ rc |= PB_CURRENT_SHARE_FAULT;
+ }
+ break;
+ default:
+ rc = -ENODATA;
+ break;
+ }
+
+ return rc;
+}
+
+static int powerps_read_word_data(struct i2c_client *client, int page, int reg)
+{
+ int rc, mfr;
+
+ switch (reg) {
+ case PMBUS_STATUS_WORD:
+ rc = pmbus_read_word_data(client, page, reg);
+ if (rc < 0)
+ return rc;
+
+ mfr = pmbus_read_byte_data(client, page,
+ PMBUS_STATUS_MFR_SPECIFIC);
+ if (mfr < 0)
+ return rc;
return mfr; ?
+
+ if (mfr & POWERPS_MFR_PS_KILL)
+ rc |= PB_STATUS_OFF;
+ break;
+ default:
+ rc = -ENODATA;
+ break;
+ }
+
+ return rc;
+}
+
+static struct pmbus_driver_info powerps_info = {
+ .pages = 1,
+ .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT |
+ PMBUS_HAVE_PIN | PMBUS_HAVE_FAN12 | PMBUS_HAVE_TEMP |
+ PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 | PMBUS_HAVE_STATUS_VOUT |
+ PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_INPUT |
+ PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_STATUS_FAN12,
+ .read_byte_data = powerps_read_byte_data,
+ .read_word_data = powerps_read_word_data,
+ .debugfs = true,
+};
+
+static int powerps_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ return pmbus_do_probe(client, id, &powerps_info);
+}
+
+static const struct i2c_device_id powerps_id[] = {
+ { "power_ps", 1 },
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, powerps_id);
+
+/* IBM provides many compatible power supplies; use a generic name. */
+static const struct of_device_id powerps_of_match[] = {
+ { .compatible = "ibm,power-ps" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, powerps_of_match);
+
+static struct i2c_driver powerps_driver = {
+ .driver = {
+ .name = "powerps",
+ .of_match_table = powerps_of_match,
+ },
+ .probe = powerps_probe,
+ .remove = pmbus_do_remove,
+ .id_table = powerps_id,
+};
+
+module_i2c_driver(powerps_driver);
+
+MODULE_AUTHOR("Eddie James");
+MODULE_DESCRIPTION("PMBus driver for POWER system power supplies");
+MODULE_LICENSE("GPL");
--
1.8.3.1