Trimming is a manufacturer-specific command provided by TPS544C20.
Since there is no generic interface for trimming yet this patch
proposes a new driver with dedicated sysfs entries for trimming
support for the component, according to its datasheet. This
allows users to access the VREF_TRIM and STORE_USER_ALL commands.
---
drivers/hwmon/pmbus/Kconfig | 10 +++
drivers/hwmon/pmbus/Makefile | 1 +
drivers/hwmon/pmbus/tps544c20.c | 164 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 175 insertions(+)
create mode 100644 drivers/hwmon/pmbus/tps544c20.c
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 40019325b517..6f46e17d2004 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -153,6 +153,16 @@ config SENSORS_TPS53679
This driver can also be built as a module. If so, the module will
be called tps53679.
+config SENSORS_TPS544C20
+ tristate "TI TPS544C20"
+ default n
+ help
+ If you say yes here you get hardware monitoring support for TI
+ TPS544C20 with trimming support.
+
+ This driver can also be built as a module. If so, the module will
+ be called tps544c20.
+
config SENSORS_UCD9000
tristate "TI UCD90120, UCD90124, UCD90160, UCD9090, UCD90910"
default n
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 459a6be3390e..5b8e0a37551a 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_SENSORS_MAX34440) += max34440.o
obj-$(CONFIG_SENSORS_MAX8688) += max8688.o
obj-$(CONFIG_SENSORS_TPS40422) += tps40422.o
obj-$(CONFIG_SENSORS_TPS53679) += tps53679.o
+obj-$(CONFIG_SENSORS_TPS544C20) += tps544c20.o
obj-$(CONFIG_SENSORS_UCD9000) += ucd9000.o
obj-$(CONFIG_SENSORS_UCD9200) += ucd9200.o
obj-$(CONFIG_SENSORS_ZL6100) += zl6100.o
diff --git a/drivers/hwmon/pmbus/tps544c20.c b/drivers/hwmon/pmbus/tps544c20.c
new file mode 100644
index 000000000000..241c030fc216
--- /dev/null
+++ b/drivers/hwmon/pmbus/tps544c20.c
@@ -0,0 +1,164 @@
+/*
+ * Hardware monitoring driver for TI TPS544C20 with trim support
+ *
+ * Copyright (c) 2017 Nokia Solutions and Networks.
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include "pmbus.h"
+
+#define VREF_TRIM_ADDR 0xD4
+#define STORE_USER_ALL_ADDR 0x15
+
+static struct pmbus_driver_info tps544c20_info = {
+ .pages = 1,
+ .format[PSC_VOLTAGE_IN] = linear,
+ .format[PSC_VOLTAGE_OUT] = linear,
+ .format[PSC_TEMPERATURE] = linear,
+ .func[0] = PMBUS_HAVE_VOUT | PMBUS_HAVE_TEMP2
+ | PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_TEMP
+ | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT,
+};
+
+static ssize_t show_vref_trim(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int ret;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ ret = pmbus_read_word_data(client, 0, VREF_TRIM_ADDR);
+ if (ret < 0) {
+ dev_err(dev, "error reading vref_trim (%d)\n", ret);
+ return ret;
+ }
+
+ ret = snprintf(buf, PAGE_SIZE, "%d\n", (int16_t) ret);
+ return ret;
+}
+
+static ssize_t store_vref_trim(struct device *dev,
+ struct device_attribute *attr, const char *buf,
+ size_t count)
+{
+ int ret;
+ int value;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ ret = sscanf(buf, "%d", &value);
+ if (ret != 1) {
+ dev_err(dev, "bad value, please write integer\n");
+ return -EINVAL;
+ }
+
+ ret = pmbus_write_word_data(client, 0, VREF_TRIM_ADDR, (int16_t) value);
+ if (ret < 0) {
+ dev_err(dev, "error writing vref_trim\n");
+ return ret;
+ }
+
+ /* Delay of at least 15 us/mV of change (0.067 mV/us), lets wait 10ms */
+ msleep(10);
+
+ return count;
+}
+
+static ssize_t set_store_user_all(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ int ret;
+ int read_value;
+ struct i2c_client *client = to_i2c_client(dev);
+
+ ret = sscanf(buf, "%d", &read_value);
+ if (ret != 1 || read_value != 1) {
+ dev_err(dev, "bad value, write 1 to store. abort\n");
+ return -EINVAL;
+ }
+
+ ret = pmbus_write_byte(client, 0, STORE_USER_ALL_ADDR);
+ if (ret < 0) {
+ dev_err(dev, "error writing store_user_all\n");
+ return ret;
+ }
+
+ return count;
+}
+
+DEVICE_ATTR(vref_trim, S_IWUSR | S_IRUGO, show_vref_trim, store_vref_trim);
+DEVICE_ATTR(store_user_all, S_IWUSR, NULL, set_store_user_all);
+
+static struct attribute *tps544c20_attributes[] = {
+ &dev_attr_vref_trim.attr,
+ &dev_attr_store_user_all.attr,
+ NULL
+};
+
+static const struct attribute_group tps544c20_group = {
+ .attrs = tps544c20_attributes,
+};
+
+static int tps544c20_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+
+ ret = pmbus_do_probe(client, id, &tps544c20_info);
+ if (ret < 0) {
+ pr_err("error during pmbus probe\n");
+ return ret;
+ }
+
+ ret = sysfs_create_group(&client->dev.kobj, &tps544c20_group);
+ if (ret < 0) {
+ pr_err("error creating sysfs\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int tps544c20_remove(struct i2c_client *client)
+{
+ sysfs_remove_group(&client->dev.kobj, &tps544c20_group);
+
+ return pmbus_do_remove(client);
+}
+
+static const struct i2c_device_id tps544c20_id[] = {
+ {"tps544c20", 0},
+ {}
+};
+
+MODULE_DEVICE_TABLE(i2c, tps544c20_id);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver tps544c20_driver = {
+ .driver = {
+ .name = "tps544c20",
+ },
+ .probe = tps544c20_probe,
+ .remove = tps544c20_remove,
+ .id_table = tps544c20_id,
+};
+
+module_i2c_driver(tps544c20_driver);
+
+MODULE_AUTHOR("Romain Porte <romain.po...@nokia.com>");
+MODULE_DESCRIPTION("PMBus driver for TI TPS544C20 with trim support");
+MODULE_LICENSE("GPL");
--
2.11.0
