[PATCH] w1: add support for DS2413 Dual Channel Addressable Switch

From: Mariusz Bialonczyk
Date: Tue Jan 01 2013 - 08:25:48 EST


Also fixes some whitespace inconsistency in Kconfig and w1_family.h
when DS2408 chip support was added.

Signed-off-by: Mariusz Bialonczyk <manio@xxxxxxxxxx>
---
drivers/w1/slaves/Kconfig | 13 ++-
drivers/w1/slaves/Makefile | 3 +-
drivers/w1/slaves/w1_ds2413.c | 177 +++++++++++++++++++++++++++++++++++++++++
drivers/w1/w1_family.h | 1 +
4 files changed, 189 insertions(+), 5 deletions(-)
create mode 100644 drivers/w1/slaves/w1_ds2413.c

diff --git a/drivers/w1/slaves/Kconfig b/drivers/w1/slaves/Kconfig
index 6752669..762561f 100644
--- a/drivers/w1/slaves/Kconfig
+++ b/drivers/w1/slaves/Kconfig
@@ -17,11 +17,16 @@ config W1_SLAVE_SMEM
simple 64bit memory rom(ds2401/ds2411/ds1990*) to your wire.

config W1_SLAVE_DS2408
- tristate "8-Channel Addressable Switch (IO Expander) 0x29 family support (DS2408)"
- help
- Say Y here if you want to use a 1-wire
+ tristate "8-Channel Addressable Switch (IO Expander) 0x29 family support (DS2408)"
+ help
+ Say Y here if you want to use a 1-wire
+ DS2408 8-Channel Addressable Switch device support

- DS2408 8-Channel Addressable Switch device support
+config W1_SLAVE_DS2413
+ tristate "Dual Channel Addressable Switch 0x3a family support (DS2413)"
+ help
+ Say Y here if you want to use a 1-wire
+ DS2413 Dual Channel Addressable Switch device support

config W1_SLAVE_DS2423
tristate "Counter 1-wire device (DS2423)"
diff --git a/drivers/w1/slaves/Makefile b/drivers/w1/slaves/Makefile
index 05188f6..06529f3 100644
--- a/drivers/w1/slaves/Makefile
+++ b/drivers/w1/slaves/Makefile
@@ -4,7 +4,8 @@

obj-$(CONFIG_W1_SLAVE_THERM) += w1_therm.o
obj-$(CONFIG_W1_SLAVE_SMEM) += w1_smem.o
-obj-$(CONFIG_W1_SLAVE_DS2408) += w1_ds2408.o
+obj-$(CONFIG_W1_SLAVE_DS2408) += w1_ds2408.o
+obj-$(CONFIG_W1_SLAVE_DS2413) += w1_ds2413.o
obj-$(CONFIG_W1_SLAVE_DS2423) += w1_ds2423.o
obj-$(CONFIG_W1_SLAVE_DS2431) += w1_ds2431.o
obj-$(CONFIG_W1_SLAVE_DS2433) += w1_ds2433.o
diff --git a/drivers/w1/slaves/w1_ds2413.c b/drivers/w1/slaves/w1_ds2413.c
new file mode 100644
index 0000000..8297862
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds2413.c
@@ -0,0 +1,177 @@
+/*
+ * w1_ds2413.c - w1 family 3a (DS2413) driver
+ * based on w1_ds2408.c by Jean-Francois Dagenais <dagenaisj@xxxxxxxxxxxx>
+ *
+ * Copyright (c) 2013 Mariusz Bialonczyk <manio@xxxxxxxxxx>
+ *
+ * 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@xxxxxxxxxx>");
+MODULE_DESCRIPTION("w1 family 3a driver for DS2413 2 Pin IO");
+
+#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 w1_f3a_read_state(
+ 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 ssize_t w1_f3a_write_output(
+ 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;
+}
+
+#define NB_SYSFS_BIN_FILES 2
+static struct bin_attribute w1_f3a_sysfs_bin_files[NB_SYSFS_BIN_FILES] = {
+ {
+ .attr = {
+ .name = "state",
+ .mode = S_IRUGO,
+ },
+ .size = 1,
+ .read = w1_f3a_read_state,
+ },
+ {
+ .attr = {
+ .name = "output",
+ .mode = S_IRUGO | S_IWUSR | S_IWGRP,
+ },
+ .size = 1,
+ .write = w1_f3a_write_output,
+ }
+};
+
+static int w1_f3a_add_slave(struct w1_slave *sl)
+{
+ int err = 0;
+ int i;
+
+ for (i = 0; i < NB_SYSFS_BIN_FILES && !err; ++i)
+ err = sysfs_create_bin_file(
+ &sl->dev.kobj,
+ &(w1_f3a_sysfs_bin_files[i]));
+ if (err)
+ while (--i >= 0)
+ sysfs_remove_bin_file(&sl->dev.kobj,
+ &(w1_f3a_sysfs_bin_files[i]));
+ return err;
+}
+
+static void w1_f3a_remove_slave(struct w1_slave *sl)
+{
+ int i;
+ for (i = NB_SYSFS_BIN_FILES - 1; i >= 0; --i)
+ sysfs_remove_bin_file(&sl->dev.kobj,
+ &(w1_f3a_sysfs_bin_files[i]));
+}
+
+static struct w1_family_ops w1_f3a_fops = {
+ .add_slave = w1_f3a_add_slave,
+ .remove_slave = w1_f3a_remove_slave,
+};
+
+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);
diff --git a/drivers/w1/w1_family.h b/drivers/w1/w1_family.h
index a1f0ce1..625dd08 100644
--- a/drivers/w1/w1_family.h
+++ b/drivers/w1/w1_family.h
@@ -39,6 +39,7 @@
#define W1_EEPROM_DS2431 0x2D
#define W1_FAMILY_DS2760 0x30
#define W1_FAMILY_DS2780 0x32
+#define W1_FAMILY_DS2413 0x3A
#define W1_THERM_DS1825 0x3B
#define W1_FAMILY_DS2781 0x3D
#define W1_THERM_DS28EA00 0x42
--
1.7.10.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/