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path: root/drivers/w1/slaves/w1_ds2780.c
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Diffstat (limited to 'drivers/w1/slaves/w1_ds2780.c')
-rw-r--r--drivers/w1/slaves/w1_ds2780.c191
1 files changed, 191 insertions, 0 deletions
diff --git a/drivers/w1/slaves/w1_ds2780.c b/drivers/w1/slaves/w1_ds2780.c
new file mode 100644
index 000000000..50e85f792
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds2780.c
@@ -0,0 +1,191 @@
+/*
+ * 1-Wire implementation for the ds2780 chip
+ *
+ * Copyright (C) 2010 Indesign, LLC
+ *
+ * Author: Clifton Barnes <cabarnes@indesign-llc.com>
+ *
+ * Based on w1-ds2760 driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
+#include <linux/idr.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+#include "../w1_family.h"
+#include "w1_ds2780.h"
+
+static int w1_ds2780_do_io(struct device *dev, char *buf, int addr,
+ size_t count, int io)
+{
+ struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+
+ if (addr > DS2780_DATA_SIZE || addr < 0)
+ return 0;
+
+ count = min_t(int, count, DS2780_DATA_SIZE - addr);
+
+ if (w1_reset_select_slave(sl) == 0) {
+ if (io) {
+ w1_write_8(sl->master, W1_DS2780_WRITE_DATA);
+ w1_write_8(sl->master, addr);
+ w1_write_block(sl->master, buf, count);
+ } else {
+ w1_write_8(sl->master, W1_DS2780_READ_DATA);
+ w1_write_8(sl->master, addr);
+ count = w1_read_block(sl->master, buf, count);
+ }
+ }
+
+ return count;
+}
+
+int w1_ds2780_io(struct device *dev, char *buf, int addr, size_t count,
+ int io)
+{
+ struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+ int ret;
+
+ if (!dev)
+ return -ENODEV;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ ret = w1_ds2780_do_io(dev, buf, addr, count, io);
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL(w1_ds2780_io);
+
+int w1_ds2780_eeprom_cmd(struct device *dev, int addr, int cmd)
+{
+ struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
+
+ if (!dev)
+ return -EINVAL;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_reset_select_slave(sl) == 0) {
+ w1_write_8(sl->master, cmd);
+ w1_write_8(sl->master, addr);
+ }
+
+ mutex_unlock(&sl->master->bus_mutex);
+ return 0;
+}
+EXPORT_SYMBOL(w1_ds2780_eeprom_cmd);
+
+static ssize_t w1_slave_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct device *dev = container_of(kobj, struct device, kobj);
+ return w1_ds2780_io(dev, buf, off, count, 0);
+}
+
+static BIN_ATTR_RO(w1_slave, DS2780_DATA_SIZE);
+
+static struct bin_attribute *w1_ds2780_bin_attrs[] = {
+ &bin_attr_w1_slave,
+ NULL,
+};
+
+static const struct attribute_group w1_ds2780_group = {
+ .bin_attrs = w1_ds2780_bin_attrs,
+};
+
+static const struct attribute_group *w1_ds2780_groups[] = {
+ &w1_ds2780_group,
+ NULL,
+};
+
+static DEFINE_IDA(bat_ida);
+
+static int w1_ds2780_add_slave(struct w1_slave *sl)
+{
+ int ret;
+ int id;
+ struct platform_device *pdev;
+
+ id = ida_simple_get(&bat_ida, 0, 0, GFP_KERNEL);
+ if (id < 0) {
+ ret = id;
+ goto noid;
+ }
+
+ pdev = platform_device_alloc("ds2780-battery", id);
+ if (!pdev) {
+ ret = -ENOMEM;
+ goto pdev_alloc_failed;
+ }
+ pdev->dev.parent = &sl->dev;
+
+ ret = platform_device_add(pdev);
+ if (ret)
+ goto pdev_add_failed;
+
+ dev_set_drvdata(&sl->dev, pdev);
+
+ return 0;
+
+pdev_add_failed:
+ platform_device_put(pdev);
+pdev_alloc_failed:
+ ida_simple_remove(&bat_ida, id);
+noid:
+ return ret;
+}
+
+static void w1_ds2780_remove_slave(struct w1_slave *sl)
+{
+ struct platform_device *pdev = dev_get_drvdata(&sl->dev);
+ int id = pdev->id;
+
+ platform_device_unregister(pdev);
+ ida_simple_remove(&bat_ida, id);
+}
+
+static struct w1_family_ops w1_ds2780_fops = {
+ .add_slave = w1_ds2780_add_slave,
+ .remove_slave = w1_ds2780_remove_slave,
+ .groups = w1_ds2780_groups,
+};
+
+static struct w1_family w1_ds2780_family = {
+ .fid = W1_FAMILY_DS2780,
+ .fops = &w1_ds2780_fops,
+};
+
+static int __init w1_ds2780_init(void)
+{
+ ida_init(&bat_ida);
+ return w1_register_family(&w1_ds2780_family);
+}
+
+static void __exit w1_ds2780_exit(void)
+{
+ w1_unregister_family(&w1_ds2780_family);
+ ida_destroy(&bat_ida);
+}
+
+module_init(w1_ds2780_init);
+module_exit(w1_ds2780_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Clifton Barnes <cabarnes@indesign-llc.com>");
+MODULE_DESCRIPTION("1-wire Driver for Maxim/Dallas DS2780 Stand-Alone Fuel Gauge IC");
+MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2780));