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-rw-r--r--drivers/hwmon/pmbus/ucd9200.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/ucd9200.c b/drivers/hwmon/pmbus/ucd9200.c
new file mode 100644
index 0000000..033d6ac
--- /dev/null
+++ b/drivers/hwmon/pmbus/ucd9200.c
@@ -0,0 +1,180 @@
+/*
+ * Hardware monitoring driver for ucd9200 series Digital PWM System Controllers
+ *
+ * Copyright (C) 2011 Ericsson AB.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/i2c/pmbus.h>
+#include "pmbus.h"
+
+#define UCD9200_PHASE_INFO 0xd2
+#define UCD9200_DEVICE_ID 0xfd
+
+enum chips { ucd9200, ucd9220, ucd9222, ucd9224, ucd9240, ucd9244, ucd9246,
+ ucd9248 };
+
+static const struct i2c_device_id ucd9200_id[] = {
+ {"ucd9200", ucd9200},
+ {"ucd9220", ucd9220},
+ {"ucd9222", ucd9222},
+ {"ucd9224", ucd9224},
+ {"ucd9240", ucd9240},
+ {"ucd9244", ucd9244},
+ {"ucd9246", ucd9246},
+ {"ucd9248", ucd9248},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, ucd9200_id);
+
+static int ucd9200_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
+ struct pmbus_driver_info *info;
+ const struct i2c_device_id *mid;
+ int i, j, ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_BLOCK_DATA))
+ return -ENODEV;
+
+ ret = i2c_smbus_read_block_data(client, UCD9200_DEVICE_ID,
+ block_buffer);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to read device ID\n");
+ return ret;
+ }
+ block_buffer[ret] = '\0';
+ dev_info(&client->dev, "Device ID %s\n", block_buffer);
+
+ for (mid = ucd9200_id; mid->name[0]; mid++) {
+ if (!strncasecmp(mid->name, block_buffer, strlen(mid->name)))
+ break;
+ }
+ if (!mid->name[0]) {
+ dev_err(&client->dev, "Unsupported device\n");
+ return -ENODEV;
+ }
+ if (id->driver_data != ucd9200 && id->driver_data != mid->driver_data)
+ dev_notice(&client->dev,
+ "Device mismatch: Configured %s, detected %s\n",
+ id->name, mid->name);
+
+ info = devm_kzalloc(&client->dev, sizeof(struct pmbus_driver_info),
+ GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ ret = i2c_smbus_read_block_data(client, UCD9200_PHASE_INFO,
+ block_buffer);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to read phase information\n");
+ return ret;
+ }
+
+ /*
+ * Calculate number of configured pages (rails) from PHASE_INFO
+ * register.
+ * Rails have to be sequential, so we can abort after finding
+ * the first unconfigured rail.
+ */
+ info->pages = 0;
+ for (i = 0; i < ret; i++) {
+ if (!block_buffer[i])
+ break;
+ info->pages++;
+ }
+ if (!info->pages) {
+ dev_err(&client->dev, "No rails configured\n");
+ return -ENODEV;
+ }
+ dev_info(&client->dev, "%d rails configured\n", info->pages);
+
+ /*
+ * Set PHASE registers on all pages to 0xff to ensure that phase
+ * specific commands will apply to all phases of a given page (rail).
+ * This only affects the READ_IOUT and READ_TEMPERATURE2 registers.
+ * READ_IOUT will return the sum of currents of all phases of a rail,
+ * and READ_TEMPERATURE2 will return the maximum temperature detected
+ * for the the phases of the rail.
+ */
+ for (i = 0; i < info->pages; i++) {
+ /*
+ * Setting PAGE & PHASE fails once in a while for no obvious
+ * reason, so we need to retry a couple of times.
+ */
+ for (j = 0; j < 3; j++) {
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i);
+ if (ret < 0)
+ continue;
+ ret = i2c_smbus_write_byte_data(client, PMBUS_PHASE,
+ 0xff);
+ if (ret < 0)
+ continue;
+ break;
+ }
+ if (ret < 0) {
+ dev_err(&client->dev,
+ "Failed to initialize PHASE registers\n");
+ return ret;
+ }
+ }
+ if (info->pages > 1)
+ i2c_smbus_write_byte_data(client, PMBUS_PAGE, 0);
+
+ info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT |
+ PMBUS_HAVE_IIN | PMBUS_HAVE_PIN |
+ PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+ PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+ PMBUS_HAVE_POUT | PMBUS_HAVE_TEMP |
+ PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
+
+ for (i = 1; i < info->pages; i++)
+ info->func[i] = PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
+ PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
+ PMBUS_HAVE_POUT |
+ PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
+
+ /* ucd9240 supports a single fan */
+ if (mid->driver_data == ucd9240)
+ info->func[0] |= PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12;
+
+ return pmbus_do_probe(client, mid, info);
+}
+
+/* This is the driver that will be inserted */
+static struct i2c_driver ucd9200_driver = {
+ .driver = {
+ .name = "ucd9200",
+ },
+ .probe = ucd9200_probe,
+ .remove = pmbus_do_remove,
+ .id_table = ucd9200_id,
+};
+
+module_i2c_driver(ucd9200_driver);
+
+MODULE_AUTHOR("Guenter Roeck");
+MODULE_DESCRIPTION("PMBus driver for TI UCD922x, UCD924x");
+MODULE_LICENSE("GPL");
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