Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / w1 / slaves / w1_ds2413.c

diff --git a/kernel/drivers/w1/slaves/w1_ds2413.c b/kernel/drivers/w1/slaves/w1_ds2413.c
new file mode 100644 (file)
index 0000000..ee28fc1
--- /dev/null
+++ b/kernel/drivers/w1/slaves/w1_ds2413.c
@@ -0,0 +1,150 @@
+/*
+ * w1_ds2413.c - w1 family 3a (DS2413) driver
+ * based on w1_ds2408.c by Jean-Francois Dagenais <dagenaisj@sonatest.com>
+ *
+ * Copyright (c) 2013 Mariusz Bialonczyk <manio@skyboo.net>
+ *
+ * This source code is licensed under the GNU General Public License,
+ * Version 2. See the file COPYING for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/device.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+
+#include "../w1.h"
+#include "../w1_int.h"
+#include "../w1_family.h"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mariusz Bialonczyk <manio@skyboo.net>");
+MODULE_DESCRIPTION("w1 family 3a driver for DS2413 2 Pin IO");
+MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2413));
+
+#define W1_F3A_RETRIES                     3
+#define W1_F3A_FUNC_PIO_ACCESS_READ        0xF5
+#define W1_F3A_FUNC_PIO_ACCESS_WRITE       0x5A
+#define W1_F3A_SUCCESS_CONFIRM_BYTE        0xAA
+
+static ssize_t state_read(struct file *filp, struct kobject *kobj,
+                         struct bin_attribute *bin_attr, char *buf, loff_t off,
+                         size_t count)
+{
+       struct w1_slave *sl = kobj_to_w1_slave(kobj);
+       dev_dbg(&sl->dev,
+               "Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
+               bin_attr->attr.name, kobj, (unsigned int)off, count, buf);
+
+       if (off != 0)
+               return 0;
+       if (!buf)
+               return -EINVAL;
+
+       mutex_lock(&sl->master->bus_mutex);
+       dev_dbg(&sl->dev, "mutex locked");
+
+       if (w1_reset_select_slave(sl)) {
+               mutex_unlock(&sl->master->bus_mutex);
+               return -EIO;
+       }
+
+       w1_write_8(sl->master, W1_F3A_FUNC_PIO_ACCESS_READ);
+       *buf = w1_read_8(sl->master);
+
+       mutex_unlock(&sl->master->bus_mutex);
+       dev_dbg(&sl->dev, "mutex unlocked");
+
+       /* check for correct complement */
+       if ((*buf & 0x0F) != ((~*buf >> 4) & 0x0F))
+               return -EIO;
+       else
+               return 1;
+}
+
+static BIN_ATTR_RO(state, 1);
+
+static ssize_t output_write(struct file *filp, struct kobject *kobj,
+                           struct bin_attribute *bin_attr, char *buf,
+                           loff_t off, size_t count)
+{
+       struct w1_slave *sl = kobj_to_w1_slave(kobj);
+       u8 w1_buf[3];
+       unsigned int retries = W1_F3A_RETRIES;
+
+       if (count != 1 || off != 0)
+               return -EFAULT;
+
+       dev_dbg(&sl->dev, "locking mutex for write_output");
+       mutex_lock(&sl->master->bus_mutex);
+       dev_dbg(&sl->dev, "mutex locked");
+
+       if (w1_reset_select_slave(sl))
+               goto error;
+
+       /* according to the DS2413 datasheet the most significant 6 bits
+          should be set to "1"s, so do it now */
+       *buf = *buf | 0xFC;
+
+       while (retries--) {
+               w1_buf[0] = W1_F3A_FUNC_PIO_ACCESS_WRITE;
+               w1_buf[1] = *buf;
+               w1_buf[2] = ~(*buf);
+               w1_write_block(sl->master, w1_buf, 3);
+
+               if (w1_read_8(sl->master) == W1_F3A_SUCCESS_CONFIRM_BYTE) {
+                       mutex_unlock(&sl->master->bus_mutex);
+                       dev_dbg(&sl->dev, "mutex unlocked, retries:%d", retries);
+                       return 1;
+               }
+               if (w1_reset_resume_command(sl->master))
+                       goto error;
+       }
+
+error:
+       mutex_unlock(&sl->master->bus_mutex);
+       dev_dbg(&sl->dev, "mutex unlocked in error, retries:%d", retries);
+       return -EIO;
+}
+
+static BIN_ATTR(output, S_IRUGO | S_IWUSR | S_IWGRP, NULL, output_write, 1);
+
+static struct bin_attribute *w1_f3a_bin_attrs[] = {
+       &bin_attr_state,
+       &bin_attr_output,
+       NULL,
+};
+
+static const struct attribute_group w1_f3a_group = {
+       .bin_attrs = w1_f3a_bin_attrs,
+};
+
+static const struct attribute_group *w1_f3a_groups[] = {
+       &w1_f3a_group,
+       NULL,
+};
+
+static struct w1_family_ops w1_f3a_fops = {
+       .groups         = w1_f3a_groups,
+};
+
+static struct w1_family w1_family_3a = {
+       .fid = W1_FAMILY_DS2413,
+       .fops = &w1_f3a_fops,
+};
+
+static int __init w1_f3a_init(void)
+{
+       return w1_register_family(&w1_family_3a);
+}
+
+static void __exit w1_f3a_exit(void)
+{
+       w1_unregister_family(&w1_family_3a);
+}
+
+module_init(w1_f3a_init);
+module_exit(w1_f3a_exit);