summaryrefslogtreecommitdiff
path: root/drivers/hwmon/pmbus/zl6100.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/hwmon/pmbus/zl6100.c')
-rw-r--r--drivers/hwmon/pmbus/zl6100.c256
1 files changed, 256 insertions, 0 deletions
diff --git a/drivers/hwmon/pmbus/zl6100.c b/drivers/hwmon/pmbus/zl6100.c
new file mode 100644
index 000000000000..2bc980006f83
--- /dev/null
+++ b/drivers/hwmon/pmbus/zl6100.c
@@ -0,0 +1,256 @@
+/*
+ * Hardware monitoring driver for ZL6100 and compatibles
+ *
+ * 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/ktime.h>
+#include <linux/delay.h>
+#include "pmbus.h"
+
+enum chips { zl2004, zl2006, zl2008, zl2105, zl2106, zl6100, zl6105 };
+
+struct zl6100_data {
+ int id;
+ ktime_t access; /* chip access time */
+ struct pmbus_driver_info info;
+};
+
+#define to_zl6100_data(x) container_of(x, struct zl6100_data, info)
+
+#define ZL6100_DEVICE_ID 0xe4
+
+#define ZL6100_WAIT_TIME 1000 /* uS */
+
+static ushort delay = ZL6100_WAIT_TIME;
+module_param(delay, ushort, 0644);
+MODULE_PARM_DESC(delay, "Delay between chip accesses in uS");
+
+/* Some chips need a delay between accesses */
+static inline void zl6100_wait(const struct zl6100_data *data)
+{
+ if (delay) {
+ s64 delta = ktime_us_delta(ktime_get(), data->access);
+ if (delta < delay)
+ udelay(delay - delta);
+ }
+}
+
+static int zl6100_read_word_data(struct i2c_client *client, int page, int reg)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ struct zl6100_data *data = to_zl6100_data(info);
+ int ret;
+
+ if (page || reg >= PMBUS_VIRT_BASE)
+ return -ENXIO;
+
+ zl6100_wait(data);
+ ret = pmbus_read_word_data(client, page, reg);
+ data->access = ktime_get();
+
+ return ret;
+}
+
+static int zl6100_read_byte_data(struct i2c_client *client, int page, int reg)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ struct zl6100_data *data = to_zl6100_data(info);
+ int ret;
+
+ if (page > 0)
+ return -ENXIO;
+
+ zl6100_wait(data);
+ ret = pmbus_read_byte_data(client, page, reg);
+ data->access = ktime_get();
+
+ return ret;
+}
+
+static int zl6100_write_word_data(struct i2c_client *client, int page, int reg,
+ u16 word)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ struct zl6100_data *data = to_zl6100_data(info);
+ int ret;
+
+ if (page || reg >= PMBUS_VIRT_BASE)
+ return -ENXIO;
+
+ zl6100_wait(data);
+ ret = pmbus_write_word_data(client, page, reg, word);
+ data->access = ktime_get();
+
+ return ret;
+}
+
+static int zl6100_write_byte(struct i2c_client *client, int page, u8 value)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ struct zl6100_data *data = to_zl6100_data(info);
+ int ret;
+
+ if (page > 0)
+ return -ENXIO;
+
+ zl6100_wait(data);
+ ret = pmbus_write_byte(client, page, value);
+ data->access = ktime_get();
+
+ return ret;
+}
+
+static const struct i2c_device_id zl6100_id[] = {
+ {"zl2004", zl2004},
+ {"zl2006", zl2006},
+ {"zl2008", zl2008},
+ {"zl2105", zl2105},
+ {"zl2106", zl2106},
+ {"zl6100", zl6100},
+ {"zl6105", zl6105},
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, zl6100_id);
+
+static int zl6100_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct zl6100_data *data;
+ struct pmbus_driver_info *info;
+ u8 device_id[I2C_SMBUS_BLOCK_MAX + 1];
+ const struct i2c_device_id *mid;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_BYTE_DATA
+ | I2C_FUNC_SMBUS_READ_BLOCK_DATA))
+ return -ENODEV;
+
+ ret = i2c_smbus_read_block_data(client, ZL6100_DEVICE_ID,
+ device_id);
+ if (ret < 0) {
+ dev_err(&client->dev, "Failed to read device ID\n");
+ return ret;
+ }
+ device_id[ret] = '\0';
+ dev_info(&client->dev, "Device ID %s\n", device_id);
+
+ mid = NULL;
+ for (mid = zl6100_id; mid->name[0]; mid++) {
+ if (!strncasecmp(mid->name, device_id, strlen(mid->name)))
+ break;
+ }
+ if (!mid->name[0]) {
+ dev_err(&client->dev, "Unsupported device\n");
+ return -ENODEV;
+ }
+ if (id->driver_data != mid->driver_data)
+ dev_notice(&client->dev,
+ "Device mismatch: Configured %s, detected %s\n",
+ id->name, mid->name);
+
+ data = kzalloc(sizeof(struct zl6100_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->id = mid->driver_data;
+
+ /*
+ * ZL2008, ZL2105, and ZL6100 are known to require a wait time
+ * between I2C accesses. ZL2004 and ZL6105 are known to be safe.
+ *
+ * Only clear the wait time for chips known to be safe. The wait time
+ * can be cleared later for additional chips if tests show that it
+ * is not needed (in other words, better be safe than sorry).
+ */
+ if (data->id == zl2004 || data->id == zl6105)
+ delay = 0;
+
+ /*
+ * Since there was a direct I2C device access above, wait before
+ * accessing the chip again.
+ * Set the timestamp, wait, then set it again. This should provide
+ * enough buffer time to be safe.
+ */
+ data->access = ktime_get();
+ zl6100_wait(data);
+ data->access = ktime_get();
+
+ info = &data->info;
+
+ info->pages = 1;
+ info->func[0] = PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT
+ | PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT
+ | PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT
+ | PMBUS_HAVE_TEMP | PMBUS_HAVE_TEMP2 | PMBUS_HAVE_STATUS_TEMP;
+
+ info->read_word_data = zl6100_read_word_data;
+ info->read_byte_data = zl6100_read_byte_data;
+ info->write_word_data = zl6100_write_word_data;
+ info->write_byte = zl6100_write_byte;
+
+ ret = pmbus_do_probe(client, mid, info);
+ if (ret)
+ goto err_mem;
+ return 0;
+
+err_mem:
+ kfree(data);
+ return ret;
+}
+
+static int zl6100_remove(struct i2c_client *client)
+{
+ const struct pmbus_driver_info *info = pmbus_get_driver_info(client);
+ const struct zl6100_data *data = to_zl6100_data(info);
+
+ pmbus_do_remove(client);
+ kfree(data);
+ return 0;
+}
+
+static struct i2c_driver zl6100_driver = {
+ .driver = {
+ .name = "zl6100",
+ },
+ .probe = zl6100_probe,
+ .remove = zl6100_remove,
+ .id_table = zl6100_id,
+};
+
+static int __init zl6100_init(void)
+{
+ return i2c_add_driver(&zl6100_driver);
+}
+
+static void __exit zl6100_exit(void)
+{
+ i2c_del_driver(&zl6100_driver);
+}
+
+MODULE_AUTHOR("Guenter Roeck");
+MODULE_DESCRIPTION("PMBus driver for ZL6100 and compatibles");
+MODULE_LICENSE("GPL");
+module_init(zl6100_init);
+module_exit(zl6100_exit);
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-26 23:44:32 +0300