[PATCH v4] hwmon: Add driver for STMicroelectronics PM6764 Voltage Regulator

[Charles]

Add the pmbus driver for the STMicroelectronics pm6764 voltage regulator.

the output voltage use the MFR_READ_VOUT 0xD4
vout value returned is linear11

Signed-off-by: Charles Hsu <hsu.yungteng@xxxxxxxxx>
---

v4:
 - Add pm6764tr to Documentation/hwmon/index.rst.
v3:
 - Add Documentation(Documentation/hwmon/pm6764tr.rst).
 - Fix include order.
v2:
 - Fix formatting.
 - Remove pmbus_do_remove.
 - Change from .probe to .probe_new.
v1:
 - Initial patchset.
---

 Documentation/hwmon/index.rst    |  1 +
 Documentation/hwmon/pm6764tr.rst | 33 ++++++++++++++
 drivers/hwmon/pmbus/Kconfig      |  9 ++++
 drivers/hwmon/pmbus/Makefile     |  1 +
 drivers/hwmon/pmbus/pm6764tr.c   | 78 ++++++++++++++++++++++++++++++++
 5 files changed, 122 insertions(+)
 create mode 100644 Documentation/hwmon/pm6764tr.rst
 create mode 100644 drivers/hwmon/pmbus/pm6764tr.c

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index b797db738225..1bbd05e41de4 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -144,6 +144,7 @@ Hardware Monitoring Kernel Drivers
    pc87360
    pc87427
    pcf8591
+   pm6764tr
    pmbus
    powr1220
    pxe1610
diff --git a/Documentation/hwmon/pm6764tr.rst 
b/Documentation/hwmon/pm6764tr.rst
new file mode 100644
index 000000000000..5e8092e39297
--- /dev/null
+++ b/Documentation/hwmon/pm6764tr.rst
@@ -0,0 +1,33 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+Kernel driver pm6764tr
+======================
+
+Supported chips:
+
+  * ST PM6764TR
+
+    Prefix: 'pm6764tr'
+
+    Addresses scanned: -
+
+    Datasheet: http://www.st.com/resource/en/data_brief/pm6764.pdf
+
+Authors:
+    <hsu.yungteng@xxxxxxxxx>
+
+Description:
+------------
+
+This driver supports the STMicroelectronics PM6764TR chip. The PM6764TR 
is a high
+performance digital controller designed to power Intel’s VR12.5 
processors and memories.
+
+The device utilizes digital technology to implement all control and 
power management
+functions to provide maximum flexibility and performance. The NVM is 
embedded to store
+custom configurations. The PM6764TR device features up to 4-phase 
programmable operation.
+
+The PM6764TR supports power state transitions featuring VFDE, and 
programmable DPM
+maintaining the best efficiency over all loading conditions without 
compromising transient
+response. The device assures fast and independent protectionagainstload 
overcurrent,
+under/overvoltage and feedback disconnections.
+
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index a25faf69fce3..9c846facce9f 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -220,6 +220,15 @@ config SENSORS_MP2975
       This driver can also be built as a module. If so, the module will
       be called mp2975.

+config SENSORS_PM6764TR
+    tristate "ST PM6764TR"
+    help
+      If you say yes here you get hardware monitoring support for ST
+      PM6764TR.
+
+      This driver can also be built as a module. If so, the module will
+      be called pm6764tr.
+
 config SENSORS_PXE1610
     tristate "Infineon PXE1610"
     help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 4c97ad0bd791..31ebdef5d4a6 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_SENSORS_MAX31785)    += max31785.o
 obj-$(CONFIG_SENSORS_MAX34440)    += max34440.o
 obj-$(CONFIG_SENSORS_MAX8688)    += max8688.o
 obj-$(CONFIG_SENSORS_MP2975)    += mp2975.o
+obj-$(CONFIG_SENSORS_PM6764TR)    += pm6764tr.o
 obj-$(CONFIG_SENSORS_PXE1610)    += pxe1610.o
 obj-$(CONFIG_SENSORS_TPS40422)    += tps40422.o
 obj-$(CONFIG_SENSORS_TPS53679)    += tps53679.o
diff --git a/drivers/hwmon/pmbus/pm6764tr.c b/drivers/hwmon/pmbus/pm6764tr.c
new file mode 100644
index 000000000000..2ab68036bb0c
--- /dev/null
+++ b/drivers/hwmon/pmbus/pm6764tr.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for STMicroelectronics digital controller 
PM6764TR
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/pmbus.h>
+#include <linux/slab.h>
+#include "pmbus.h"
+
+#define PM6764TR_PMBUS_READ_VOUT    0xD4
+
+static int pm6764tr_read_word_data(struct i2c_client *client, int page, 
int reg)
+{
+    int ret;
+
+    switch (reg) {
+    case PMBUS_VIRT_READ_VMON:
+        ret = pmbus_read_word_data(client, page, PM6764TR_PMBUS_READ_VOUT);
+        break;
+    default:
+        ret = -ENODATA;
+        break;
+    }
+    return ret;
+}
+
+static struct pmbus_driver_info pm6764tr_info = {
+    .pages = 1,
+    .format[PSC_VOLTAGE_IN] = linear,
+    .format[PSC_VOLTAGE_OUT] = vid,
+    .format[PSC_TEMPERATURE] = linear,
+    .format[PSC_CURRENT_OUT] = linear,
+    .format[PSC_POWER] = linear,
+    .func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN |  PMBUS_HAVE_PIN |
+        PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT | PMBUS_HAVE_VMON |
+        PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_VOUT |
+        PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP,
+    .read_word_data = pm6764tr_read_word_data,
+};
+
+static int pm6764tr_probe(struct i2c_client *client,
+              const struct i2c_device_id *id)
+{
+    return pmbus_do_probe(client, id, &pm6764tr_info);
+}
+
+static const struct i2c_device_id pm6764tr_id[] = {
+    {"pm6764tr", 0},
+    {}
+};
+MODULE_DEVICE_TABLE(i2c, pm6764tr_id);
+
+static const struct of_device_id pm6764tr_of_match[] = {
+    {.compatible = "pm6764tr"},
+    {}
+};
+
+/* This is the driver that will be inserted */
+static struct i2c_driver pm6764tr_driver = {
+    .driver = {
+           .name = "pm6764tr",
+           .of_match_table = of_match_ptr(pm6764tr_of_match),
+           },
+    .probe_new = pm6764tr_probe,
+    .id_table = pm6764tr_id,
+};
+
+module_i2c_driver(pm6764tr_driver);
+
+MODULE_AUTHOR("Charles Hsu");
+MODULE_DESCRIPTION("PMBus driver for  ST PM6764TR");
+MODULE_LICENSE("GPL");
--
2.25.1