From:   Lakshmi Yadlapati <lakshmiy@us.ibm.com>
To:     linux@roeck-us.net, jdelvare@suse.com,
        linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org
Cc:     Lakshmi Yadlapati <lakshmiy@us.ibm.com>
Subject: [PATCH 3/4] hwmon: (pmbus/acbel-crps) Add Acbel CRPS power supply driver
Date:   Wed, 15 Mar 2023 13:53:03 -0500
Message-Id: <20230315185303.960368-1-lakshmiy@us.ibm.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Add the driver to support Acbel CRPS power supply.

Signed-off-by: Lakshmi Yadlapati <lakshmiy@us.ibm.com>
---
 drivers/hwmon/pmbus/Kconfig      |   9 +
 drivers/hwmon/pmbus/Makefile     |   1 +
 drivers/hwmon/pmbus/acbel-crps.c | 311 +++++++++++++++++++++++++++++++
 3 files changed, 321 insertions(+)
 create mode 100644 drivers/hwmon/pmbus/acbel-crps.c

diff --git a/drivers/hwmon/pmbus/Kconfig b/drivers/hwmon/pmbus/Kconfig
index 59d9a7430499..9fe7ac94cfa2 100644
--- a/drivers/hwmon/pmbus/Kconfig
+++ b/drivers/hwmon/pmbus/Kconfig
@@ -27,6 +27,15 @@ config SENSORS_PMBUS
 	  This driver can also be built as a module. If so, the module will
 	  be called pmbus.
 
+config SENSORS_ACBEL_CRPS
+	tristate "ACBEL CRPS Power Supply"
+	help
+	  If you say yes here you get hardware monitoring support for the ACBEL
+	  CRPS power supply.
+
+	  This driver can also be built as a module. If so, the module will
+	  be called acbel-crps.
+
 config SENSORS_ADM1266
 	tristate "Analog Devices ADM1266 Sequencer"
 	select CRC8
diff --git a/drivers/hwmon/pmbus/Makefile b/drivers/hwmon/pmbus/Makefile
index 3ae019916267..39aef0cb9934 100644
--- a/drivers/hwmon/pmbus/Makefile
+++ b/drivers/hwmon/pmbus/Makefile
@@ -5,6 +5,7 @@
 
 obj-$(CONFIG_PMBUS)		+= pmbus_core.o
 obj-$(CONFIG_SENSORS_PMBUS)	+= pmbus.o
+obj-$(CONFIG_SENSORS_ACBEL_CRPS) += acbel-crps.o
 obj-$(CONFIG_SENSORS_ADM1266)	+= adm1266.o
 obj-$(CONFIG_SENSORS_ADM1275)	+= adm1275.o
 obj-$(CONFIG_SENSORS_BEL_PFE)	+= bel-pfe.o
diff --git a/drivers/hwmon/pmbus/acbel-crps.c b/drivers/hwmon/pmbus/acbel-crps.c
new file mode 100644
index 000000000000..f7779f0fbb2d
--- /dev/null
+++ b/drivers/hwmon/pmbus/acbel-crps.c
@@ -0,0 +1,311 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2023 IBM Corp.
+ */
+
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/pmbus.h>
+#include <linux/hwmon-sysfs.h>
+#include "pmbus.h"
+
+#define CRPS_MFG_ID_CMD                 0x99
+#define CRPS_MFG_MODEL_CMD              0x9A
+#define CRPS_MFG_REVISION_CMD           0x9B
+#define CRPS_MFG_LOCATION_CMD           0x9C
+#define CRPS_MFG_SERIAL_CMD             0x9E
+#define CRPS_CCIN_CMD                   CRPS_MFG_SERIAL_CMD
+
+/* STATUS_VOUT */
+#define CRPS_STATUS_UV_FAULT            BIT(4)
+#define CRPS_STATUS_OV_FAULT            BIT(7)
+
+/* STATUS_IOUT */
+#define CRPS_STATUS_OP_WARNING          BIT(0)
+#define CRPS_STATUS_OP_FAULT            BIT(1)
+#define CRPS_STATUS_OC_WARNING          BIT(5)
+#define CRPS_STATUS_OC_FAULT            BIT(7)
+
+/* STATUS_TEMP */
+#define CRPS_STATUS_OT_WARNING          BIT(6)
+#define CRPS_STATUS_OT_FAULT            BIT(7)
+
+/* STATUS_FAN12 */
+#define CRPS_FAN1_SPEED_OVERRIDE        BIT(2)
+#define CRPS_FAN1_WARNING               BIT(5)
+#define CRPS_FAN1_FAULT                 BIT(7)
+
+enum {
+	CRPS_DEBUGFS_MFG_ID,
+	CRPS_DEBUGFS_MFG_MODEL,
+	CRPS_DEBUGFS_MFG_REVISION,
+	CRPS_DEBUGFS_MFG_LOCATION,
+	CRPS_DEBUGFS_MFG_SERIAL,
+	CRPS_DEBUGFS_CCIN,
+	CRPS_DEBUGFS_NUM_ENTRIES
+};
+
+struct acbel_crps {
+	struct i2c_client *client;
+	int debugfs_entries[CRPS_DEBUGFS_NUM_ENTRIES];
+};
+
+static const struct i2c_device_id acbel_crps_id[] = {
+	{ "acbel_crps" },
+	{ }
+};
+#define to_psu(x, y) container_of((x), struct acbel_crps, debugfs_entries[(y)])
+
+static ssize_t acbel_crps_debugfs_read(struct file *file, char __user *buf,
+				       size_t count, loff_t *ppos)
+{
+	u8 cmd;
+	int rc;
+	int *idxp = file->private_data;
+	int idx = *idxp;
+	struct acbel_crps *psu = to_psu(idxp, idx);
+	char data[I2C_SMBUS_BLOCK_MAX + 2] = { 0 };
+
+	pmbus_set_page(psu->client, 0, 0xff);
+
+	switch (idx) {
+	case CRPS_DEBUGFS_MFG_ID:
+		cmd = CRPS_MFG_ID_CMD;
+		break;
+	case CRPS_DEBUGFS_MFG_MODEL:
+		cmd = CRPS_MFG_MODEL_CMD;
+		break;
+	case CRPS_DEBUGFS_MFG_REVISION:
+		cmd = CRPS_MFG_REVISION_CMD;
+		break;
+	case CRPS_DEBUGFS_MFG_LOCATION:
+		cmd = CRPS_MFG_LOCATION_CMD;
+		break;
+	case CRPS_DEBUGFS_MFG_SERIAL:
+		cmd = CRPS_MFG_SERIAL_CMD;
+		break;
+	case CRPS_DEBUGFS_CCIN:
+		cmd = CRPS_CCIN_CMD;
+		rc = i2c_smbus_read_block_data(psu->client, cmd, data);
+		if (rc < 0)
+			return rc;
+		data[4] = '\n';
+		data[5] = '\0';
+		rc = 6;
+		goto done;
+	default:
+		return -EINVAL;
+	}
+
+	rc = i2c_smbus_read_block_data(psu->client, cmd, data);
+	if (rc < 0)
+		return rc;
+	data[rc] = '\n';
+	rc += 2;
+done:
+	return simple_read_from_buffer(buf, count, ppos, data, rc);
+}
+
+static const struct file_operations acbel_crps_fops = {
+	.llseek = noop_llseek,
+	.read = acbel_crps_debugfs_read,
+	.open = simple_open,
+};
+
+static int acbel_crps_read_word_data(struct i2c_client *client, int page,
+				     int phase, int reg)
+{
+	int ret = 0;
+
+	if (page > 0)
+		return -ENXIO;
+
+	switch (reg) {
+	case PMBUS_VOUT_OV_FAULT_LIMIT:
+	case PMBUS_VOUT_UV_FAULT_LIMIT:
+	case PMBUS_IOUT_OC_FAULT_LIMIT:
+	case PMBUS_IOUT_OC_WARN_LIMIT:
+	case PMBUS_OT_WARN_LIMIT:
+	case PMBUS_IIN_OC_FAULT_LIMIT:
+	case PMBUS_IIN_OC_WARN_LIMIT:
+	case PMBUS_POUT_OP_FAULT_LIMIT:
+	case PMBUS_POUT_OP_WARN_LIMIT:
+	case PMBUS_MFR_VIN_MIN:
+	case PMBUS_MFR_VIN_MAX:
+	case PMBUS_MFR_IIN_MAX:
+	case PMBUS_MFR_PIN_MAX:
+	case PMBUS_MFR_VOUT_MIN:
+	case PMBUS_MFR_VOUT_MAX:
+	case PMBUS_MFR_IOUT_MAX:
+	case PMBUS_MFR_POUT_MAX:
+	case PMBUS_PIN_OP_WARN_LIMIT:
+	case PMBUS_READ_VIN:
+	case PMBUS_READ_IIN:
+	case PMBUS_READ_VOUT:
+	case PMBUS_READ_IOUT:
+	case PMBUS_READ_TEMPERATURE_1:
+	case PMBUS_READ_TEMPERATURE_2:
+	case PMBUS_READ_TEMPERATURE_3:
+	case PMBUS_READ_FAN_SPEED_1:
+	case PMBUS_READ_POUT:
+	case PMBUS_READ_PIN:
+		ret = pmbus_read_word_data(client, page, 0xff, reg);
+		break;
+	default:
+		ret = -EOPNOTSUPP;
+		break;
+	}
+	return ret;
+}
+
+static int acbel_crps_read_byte_data(struct i2c_client *client, int page,
+				     int reg)
+{
+	int ret = 0;
+	int mfg_status;
+
+	if (page >= 0) {
+		ret = pmbus_set_page(client, page, 0xff);
+		if (ret < 0)
+			return ret;
+	}
+
+	switch (reg) {
+	case PMBUS_STATUS_VOUT:
+	case PMBUS_STATUS_IOUT:
+	case PMBUS_STATUS_TEMPERATURE:
+	case PMBUS_STATUS_FAN_12:
+		mfg_status = pmbus_read_word_data(client, 0, 0xff,
+						  PMBUS_STATUS_MFR_SPECIFIC);
+		if (mfg_status < 0)
+			return mfg_status;
+
+		if (reg == PMBUS_STATUS_VOUT) {
+			if (mfg_status & CRPS_STATUS_OV_FAULT)
+				ret |= PB_VOLTAGE_OV_FAULT;
+			else if (mfg_status & CRPS_STATUS_UV_FAULT)
+				ret |= PB_VOLTAGE_UV_FAULT;
+		} else if (reg == PMBUS_STATUS_IOUT) {
+			if (mfg_status & CRPS_STATUS_OC_FAULT)
+				ret |= PB_IOUT_OC_FAULT;
+			else if (mfg_status & CRPS_STATUS_OC_WARNING)
+				ret |= PB_IOUT_OC_WARNING;
+			else if (mfg_status & CRPS_STATUS_OP_FAULT)
+				ret |= PB_POUT_OP_FAULT;
+			else if (mfg_status & CRPS_STATUS_OP_WARNING)
+				ret |= PB_POUT_OP_WARNING;
+		} else if (reg == PMBUS_STATUS_TEMPERATURE) {
+			if (mfg_status & CRPS_STATUS_OT_FAULT)
+				ret |= PB_TEMP_OT_FAULT;
+			else if (mfg_status & CRPS_STATUS_OT_WARNING)
+				ret |= PB_TEMP_OT_WARNING;
+		} else if (reg == PMBUS_STATUS_FAN_12) {
+			if (mfg_status & CRPS_FAN1_FAULT)
+				ret |= PB_FAN_FAN1_FAULT;
+			else if (mfg_status & CRPS_FAN1_WARNING)
+				ret |= PB_FAN_FAN1_WARNING;
+			else if (mfg_status & CRPS_FAN1_SPEED_OVERRIDE)
+				ret |= PB_FAN_FAN1_SPEED_OVERRIDE;
+		}
+		break;
+	default:
+		ret = -ENODATA;
+		break;
+	}
+	return ret;
+}
+
+static struct pmbus_driver_info acbel_crps_info = {
+        .pages = 1,
+        .func[0] =  PMBUS_HAVE_VIN | PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
+                    PMBUS_HAVE_VOUT | PMBUS_HAVE_IOUT | PMBUS_HAVE_POUT |
+                    PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_TEMP3 |
+                    PMBUS_HAVE_FAN12 |
+                    PMBUS_HAVE_STATUS_VOUT | PMBUS_HAVE_STATUS_IOUT |
+                    PMBUS_HAVE_STATUS_TEMP | PMBUS_HAVE_STATUS_INPUT |
+                    PMBUS_HAVE_STATUS_FAN12 | PMBUS_MFR_IIN_MAX,
+        .read_word_data = acbel_crps_read_word_data,
+        .read_byte_data = acbel_crps_read_byte_data,
+};
+
+
+static int acbel_crps_probe(struct i2c_client *client)
+{
+	struct dentry *acbel_crps_dir;
+	struct dentry *debugfs;
+	struct acbel_crps *psu;
+	int rc, i;
+
+	rc = pmbus_do_probe(client, &acbel_crps_info);
+        if (rc)
+                return rc;
+	/*
+         * Don't fail the probe if there isn't enough memory for debugfs.
+         */
+	psu = devm_kzalloc(&client->dev, sizeof(*psu), GFP_KERNEL);
+	if (!psu)
+		return 0;
+
+	psu->client = client;
+
+	debugfs = pmbus_get_debugfs_dir(client);
+	if (!debugfs)
+		return 0;
+
+	acbel_crps_dir = debugfs_create_dir(client->name, debugfs);
+	if (!acbel_crps_dir)
+		return 0;
+
+	for (i = 0; i < CRPS_DEBUGFS_NUM_ENTRIES; ++i)
+		psu->debugfs_entries[i] = i;
+
+	debugfs_create_file("mfg_id", 0444, acbel_crps_dir,
+			    &psu->debugfs_entries[CRPS_DEBUGFS_MFG_ID],
+			    &acbel_crps_fops);
+
+	debugfs_create_file("part_number", 0444, acbel_crps_dir,
+			    &psu->debugfs_entries[CRPS_DEBUGFS_MFG_MODEL],
+			    &acbel_crps_fops);
+
+	debugfs_create_file("fw_version", 0444, acbel_crps_dir,
+			    &psu->debugfs_entries[CRPS_DEBUGFS_MFG_REVISION],
+			    &acbel_crps_fops);
+
+	debugfs_create_file("mfg_location", 0444, acbel_crps_dir,
+			    &psu->debugfs_entries[CRPS_DEBUGFS_MFG_LOCATION],
+			    &acbel_crps_fops);
+
+	debugfs_create_file("serial_number", 0444, acbel_crps_dir,
+			    &psu->debugfs_entries[CRPS_DEBUGFS_MFG_SERIAL],
+			    &acbel_crps_fops);
+
+	debugfs_create_file("ccin", 0444, acbel_crps_dir,
+			    &psu->debugfs_entries[CRPS_DEBUGFS_CCIN],
+			    &acbel_crps_fops);
+	return 0;
+}
+
+static const struct of_device_id acbel_crps_of_match[] = {
+	{ .compatible = "acbel,crps"},
+	{}
+};
+MODULE_DEVICE_TABLE(of, acbel_crps_of_match);
+
+static struct i2c_driver acbel_crps_driver = {
+	.driver = {
+		.name = "acbel-crps",
+		.of_match_table = acbel_crps_of_match,
+	},
+	.probe_new = acbel_crps_probe,
+	.id_table = acbel_crps_id,
+};
+
+module_i2c_driver(acbel_crps_driver);
+
+MODULE_AUTHOR("Lakshmi Yadlapati");
+MODULE_DESCRIPTION("PMBus driver for AcBel Power System power supplies");
+MODULE_LICENSE("GPL");
+MODULE_IMPORT_NS(PMBUS);
-- 
2.37.2