[PATCH v5] hwmon: Add driver for the TEXAS TPS546D24 Buck Converter.

[Duke Du]

From: Duke Du <dukedu83@xxxxxxxxx>

Add the pmbus driver for TEXAS tps546d24 Buck Converter.
The vout mode of tps546d24 supported relative data format,
which is not supported by the PMBus core.

Signed-off-by: Duke Du <dukedu83@xxxxxxxxx>
---
Change in v1:
    Initial patchset.
Change in v2:
    Correct the tps546d24.rst format.
Change in v3:
    1. Modify the patch description.
    2. Put the change log between the dashes and diffstat.
Change in v4:
    1. Modify the patch description.
    2. Clear the bit 7 of PMBUS_VOUT_MODE to change the mode from relative
       to absolute.
    3. Add the vendor prefix.
Change in v5:
    1. Update the patch description.
    2. Extend the title underline at tps546d24.rst line 4.
    3. Add error handler and cover the edge case.
---
---
 Documentation/hwmon/index.rst     |  1 +
 Documentation/hwmon/tps546d24.rst | 35 +++++++++++++++++++
 MAINTAINERS                       |  7 ++++
 drivers/hwmon/pmbus/Kconfig       |  9 +++++
 drivers/hwmon/pmbus/Makefile      |  1 +
 drivers/hwmon/pmbus/tps546d24.c   | 71 +++++++++++++++++++++++++++++++++++++++
 6 files changed, 124 insertions(+)
 create mode 100644 Documentation/hwmon/tps546d24.rst
 create mode 100644 drivers/hwmon/pmbus/tps546d24.c

diff --git a/Documentation/hwmon/index.rst b/Documentation/hwmon/index.rst
index f7113b0..d3eede4 100644
--- a/Documentation/hwmon/index.rst
+++ b/Documentation/hwmon/index.rst
@@ -205,6 +205,7 @@ Hardware Monitoring Kernel Drivers
    tps23861
    tps40422
    tps53679
+   tps546d24
    twl4030-madc-hwmon
    ucd9000
    ucd9200
diff --git a/Documentation/hwmon/tps546d24.rst b/Documentation/hwmon/tps546d24.rst
new file mode 100644
index 0000000..97adb8a
--- /dev/null
+++ b/Documentation/hwmon/tps546d24.rst
@@ -0,0 +1,35 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+Kernel driver tps546d24
+=======================
+
+Supported chips:
+
+  * TI TPS546D24
+
+    Prefix: 'tps546d24'
+
+    Addresses scanned: -
+
+    Datasheet: https://www.ti.com/lit/gpn/tps546d24
+
+Author: Duke Du <dukedu83@xxxxxxxxx>
+
+
+Description
+-----------
+
+The TPS546D24A is a highly integrated, non-isolated DC/DC converter capable
+of high frequency operation and 40-A current output from a 7-mm x 5-mm
+package.
+
+Two, three, and four TPS546D24A devices can be interconnected
+to provide up to 160 A on a single output. The device has an option to
+overdrive the internal 5-V LDO with an external 5-V supply via the VDD5
+pin to improve efficiency and reduce power dissipation of the converter.
+
+
+Platform data support
+---------------------
+
+The driver supports standard PMBus driver platform data.
diff --git a/MAINTAINERS b/MAINTAINERS
index 8a5012b..fa2d4fb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -20583,6 +20583,13 @@ Q:	https://patchwork.kernel.org/project/linux-integrity/list/
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git
 F:	drivers/char/tpm/
 
+TPS546D24 DRIVER
+M:	Duke Du <dukedu83@xxxxxxxxx>
+L:	linux-hwmon@xxxxxxxxxxxxxxx
+S:	Maintained
+F:	Documentation/hwmon/tps546d24.rst
+F:	drivers/hwmon/pmbus/tps546d24.c
+
 TRACING
 M:	Steven Rostedt <rostedt@xxxxxxxxxxx>
 M:	Ingo Molnar <mingo@xxxxxxxxxx>
diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 951e4a9..89668af 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -397,6 +397,15 @@ config SENSORS_TPS53679
 	  This driver can also be built as a module. If so, the module will
 	  be called tps53679.
 
+config SENSORS_TPS546D24
+	tristate "TPS546D24"
+	help
+	  If you say yes here you get hardware monitoring support for TEXAS
+	  TPS546D24.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called tps546d24
+
 config SENSORS_UCD9000
 	tristate "TI UCD90120, UCD90124, UCD90160, UCD90320, UCD9090, UCD90910"
 	help
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index e2fe86f..0002dbe 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -41,6 +41,7 @@ obj-$(CONFIG_SENSORS_Q54SJ108A2)	+= q54sj108a2.o
 obj-$(CONFIG_SENSORS_STPDDC60)	+= stpddc60.o
 obj-$(CONFIG_SENSORS_TPS40422)	+= tps40422.o
 obj-$(CONFIG_SENSORS_TPS53679)	+= tps53679.o
+obj-$(CONFIG_SENSORS_TPS546D24)	+= tps546d24.o
 obj-$(CONFIG_SENSORS_UCD9000)	+= ucd9000.o
 obj-$(CONFIG_SENSORS_UCD9200)	+= ucd9200.o
 obj-$(CONFIG_SENSORS_XDPE122)	+= xdpe12284.o
diff --git a/drivers/hwmon/pmbus/tps546d24.c b/drivers/hwmon/pmbus/tps546d24.c
new file mode 100644
index 0000000..ef2b0be
--- /dev/null
+++ b/drivers/hwmon/pmbus/tps546d24.c
@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hardware monitoring driver for TEXAS TPS546D24 buck converter
+ */
+
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+#include "pmbus.h"
+
+static struct pmbus_driver_info tps546d24_info = {
+	.pages = 1,
+	.format[PSC_VOLTAGE_IN] = linear,
+	.format[PSC_VOLTAGE_OUT] = linear,
+	.format[PSC_TEMPERATURE] = linear,
+	.format[PSC_CURRENT_OUT] = linear,
+	.func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_IIN
+			| PMBUS_HAVE_IOUT | PMBUS_HAVE_VOUT
+			| PMBUS_HAVE_STATUS_IOUT | PMBUS_HAVE_STATUS_VOUT
+			| PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP,
+};
+
+static int tps546d24_probe(struct i2c_client *client)
+{
+	int reg;
+
+	reg = i2c_smbus_read_byte_data(client, PMBUS_VOUT_MODE);
+	if (reg < 0)
+		return reg;
+
+	if (reg & 0x80) {
+		int err;
+
+		err = i2c_smbus_write_byte_data(client, PMBUS_VOUT_MODE, reg & 0x7f);
+		if (err < 0)
+			return err;
+	}
+	return pmbus_do_probe(client, &tps546d24_info);
+}
+
+static const struct i2c_device_id tps546d24_id[] = {
+	{"tps546d24", 0},
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, tps546d24_id);
+
+static const struct of_device_id tps546d24_of_match[] = {
+	{.compatible = "ti,tps546d24"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, tps546d24_of_match);
+
+/* This is the driver that will be inserted */
+static struct i2c_driver tps546d24_driver = {
+	.driver = {
+		   .name = "tps546d24",
+		   .of_match_table = of_match_ptr(tps546d24_of_match),
+	   },
+	.probe_new = tps546d24_probe,
+	.id_table = tps546d24_id,
+};
+
+module_i2c_driver(tps546d24_driver);
+
+MODULE_AUTHOR("Duke Du <dukedu83@xxxxxxxxx>");
+MODULE_DESCRIPTION("PMBus driver for TI tps546d24");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);
-- 
2.7.4