Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 353 insertions, 0 deletions

diff --git a/drivers/w1/slaves/w1_ds2408.c b/drivers/w1/slaves/w1_ds2408.c
new file mode 100644
index 000000000..ad102c577
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds2408.c
@@ -0,0 +1,353 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *	w1_ds2408.c - w1 family 29 (DS2408) driver
+ *
+ * Copyright (c) 2010 Jean-Francois Dagenais <dagenaisj@sonatest.com>
+ */
+
+#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 <linux/w1.h>
+
+#define W1_FAMILY_DS2408	0x29
+
+#define W1_F29_RETRIES		3
+
+#define W1_F29_REG_LOGIG_STATE             0x88 /* R */
+#define W1_F29_REG_OUTPUT_LATCH_STATE      0x89 /* R */
+#define W1_F29_REG_ACTIVITY_LATCH_STATE    0x8A /* R */
+#define W1_F29_REG_COND_SEARCH_SELECT_MASK 0x8B /* RW */
+#define W1_F29_REG_COND_SEARCH_POL_SELECT  0x8C /* RW */
+#define W1_F29_REG_CONTROL_AND_STATUS      0x8D /* RW */
+
+#define W1_F29_FUNC_READ_PIO_REGS          0xF0
+#define W1_F29_FUNC_CHANN_ACCESS_READ      0xF5
+#define W1_F29_FUNC_CHANN_ACCESS_WRITE     0x5A
+/* also used to write the control/status reg (0x8D): */
+#define W1_F29_FUNC_WRITE_COND_SEARCH_REG  0xCC
+#define W1_F29_FUNC_RESET_ACTIVITY_LATCHES 0xC3
+
+#define W1_F29_SUCCESS_CONFIRM_BYTE        0xAA
+
+static int _read_reg(struct w1_slave *sl, u8 address, unsigned char* buf)
+{
+	u8 wrbuf[3];
+	dev_dbg(&sl->dev,
+			"Reading with slave: %p, reg addr: %0#4x, buff addr: %p",
+			sl, (unsigned int)address, buf);
+
+	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;
+	}
+
+	wrbuf[0] = W1_F29_FUNC_READ_PIO_REGS;
+	wrbuf[1] = address;
+	wrbuf[2] = 0;
+	w1_write_block(sl->master, wrbuf, 3);
+	*buf = w1_read_8(sl->master);
+
+	mutex_unlock(&sl->master->bus_mutex);
+	dev_dbg(&sl->dev, "mutex unlocked");
+	return 1;
+}
+
+static ssize_t state_read(struct file *filp, struct kobject *kobj,
+			  struct bin_attribute *bin_attr, char *buf, loff_t off,
+			  size_t count)
+{
+	dev_dbg(&kobj_to_w1_slave(kobj)->dev,
+		"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
+		bin_attr->attr.name, kobj, (unsigned int)off, count, buf);
+	if (count != 1 || off != 0)
+		return -EFAULT;
+	return _read_reg(kobj_to_w1_slave(kobj), W1_F29_REG_LOGIG_STATE, buf);
+}
+
+static ssize_t output_read(struct file *filp, struct kobject *kobj,
+			   struct bin_attribute *bin_attr, char *buf,
+			   loff_t off, size_t count)
+{
+	dev_dbg(&kobj_to_w1_slave(kobj)->dev,
+		"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
+		bin_attr->attr.name, kobj, (unsigned int)off, count, buf);
+	if (count != 1 || off != 0)
+		return -EFAULT;
+	return _read_reg(kobj_to_w1_slave(kobj),
+					 W1_F29_REG_OUTPUT_LATCH_STATE, buf);
+}
+
+static ssize_t activity_read(struct file *filp, struct kobject *kobj,
+			     struct bin_attribute *bin_attr, char *buf,
+			     loff_t off, size_t count)
+{
+	dev_dbg(&kobj_to_w1_slave(kobj)->dev,
+		"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
+		bin_attr->attr.name, kobj, (unsigned int)off, count, buf);
+	if (count != 1 || off != 0)
+		return -EFAULT;
+	return _read_reg(kobj_to_w1_slave(kobj),
+					 W1_F29_REG_ACTIVITY_LATCH_STATE, buf);
+}
+
+static ssize_t cond_search_mask_read(struct file *filp, struct kobject *kobj,
+				     struct bin_attribute *bin_attr, char *buf,
+				     loff_t off, size_t count)
+{
+	dev_dbg(&kobj_to_w1_slave(kobj)->dev,
+		"Reading %s kobj: %p, off: %0#10x, count: %zu, buff addr: %p",
+		bin_attr->attr.name, kobj, (unsigned int)off, count, buf);
+	if (count != 1 || off != 0)
+		return -EFAULT;
+	return _read_reg(kobj_to_w1_slave(kobj),
+		W1_F29_REG_COND_SEARCH_SELECT_MASK, buf);
+}
+
+static ssize_t cond_search_polarity_read(struct file *filp,
+					 struct kobject *kobj,
+					 struct bin_attribute *bin_attr,
+					 char *buf, loff_t off, size_t count)
+{
+	if (count != 1 || off != 0)
+		return -EFAULT;
+	return _read_reg(kobj_to_w1_slave(kobj),
+		W1_F29_REG_COND_SEARCH_POL_SELECT, buf);
+}
+
+static ssize_t status_control_read(struct file *filp, struct kobject *kobj,
+				   struct bin_attribute *bin_attr, char *buf,
+				   loff_t off, size_t count)
+{
+	if (count != 1 || off != 0)
+		return -EFAULT;
+	return _read_reg(kobj_to_w1_slave(kobj),
+		W1_F29_REG_CONTROL_AND_STATUS, buf);
+}
+
+#ifdef CONFIG_W1_SLAVE_DS2408_READBACK
+static bool optional_read_back_valid(struct w1_slave *sl, u8 expected)
+{
+	u8 w1_buf[3];
+
+	if (w1_reset_resume_command(sl->master))
+		return false;
+
+	w1_buf[0] = W1_F29_FUNC_READ_PIO_REGS;
+	w1_buf[1] = W1_F29_REG_OUTPUT_LATCH_STATE;
+	w1_buf[2] = 0;
+
+	w1_write_block(sl->master, w1_buf, 3);
+
+	return (w1_read_8(sl->master) == expected);
+}
+#else
+static bool optional_read_back_valid(struct w1_slave *sl, u8 expected)
+{
+	return true;
+}
+#endif
+
+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_F29_RETRIES;
+	ssize_t bytes_written = -EIO;
+
+	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 out;
+
+	do {
+		w1_buf[0] = W1_F29_FUNC_CHANN_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_F29_SUCCESS_CONFIRM_BYTE &&
+		    optional_read_back_valid(sl, *buf)) {
+			bytes_written = 1;
+			goto out;
+		}
+
+		if (w1_reset_resume_command(sl->master))
+			goto out; /* unrecoverable error */
+		/* try again, the slave is ready for a command */
+	} while (--retries);
+
+out:
+	mutex_unlock(&sl->master->bus_mutex);
+
+	dev_dbg(&sl->dev, "%s, mutex unlocked retries:%d\n",
+		(bytes_written > 0) ? "succeeded" : "error", retries);
+
+	return bytes_written;
+}
+
+
+/**
+ * Writing to the activity file resets the activity latches.
+ */
+static ssize_t activity_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);
+	unsigned int retries = W1_F29_RETRIES;
+
+	if (count != 1 || off != 0)
+		return -EFAULT;
+
+	mutex_lock(&sl->master->bus_mutex);
+
+	if (w1_reset_select_slave(sl))
+		goto error;
+
+	while (retries--) {
+		w1_write_8(sl->master, W1_F29_FUNC_RESET_ACTIVITY_LATCHES);
+		if (w1_read_8(sl->master) == W1_F29_SUCCESS_CONFIRM_BYTE) {
+			mutex_unlock(&sl->master->bus_mutex);
+			return 1;
+		}
+		if (w1_reset_resume_command(sl->master))
+			goto error;
+	}
+
+error:
+	mutex_unlock(&sl->master->bus_mutex);
+	return -EIO;
+}
+
+static ssize_t status_control_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[4];
+	unsigned int retries = W1_F29_RETRIES;
+
+	if (count != 1 || off != 0)
+		return -EFAULT;
+
+	mutex_lock(&sl->master->bus_mutex);
+
+	if (w1_reset_select_slave(sl))
+		goto error;
+
+	while (retries--) {
+		w1_buf[0] = W1_F29_FUNC_WRITE_COND_SEARCH_REG;
+		w1_buf[1] = W1_F29_REG_CONTROL_AND_STATUS;
+		w1_buf[2] = 0;
+		w1_buf[3] = *buf;
+
+		w1_write_block(sl->master, w1_buf, 4);
+		if (w1_reset_resume_command(sl->master))
+			goto error;
+
+		w1_buf[0] = W1_F29_FUNC_READ_PIO_REGS;
+		w1_buf[1] = W1_F29_REG_CONTROL_AND_STATUS;
+		w1_buf[2] = 0;
+
+		w1_write_block(sl->master, w1_buf, 3);
+		if (w1_read_8(sl->master) == *buf) {
+			/* success! */
+			mutex_unlock(&sl->master->bus_mutex);
+			return 1;
+		}
+	}
+error:
+	mutex_unlock(&sl->master->bus_mutex);
+
+	return -EIO;
+}
+
+/*
+ * This is a special sequence we must do to ensure the P0 output is not stuck
+ * in test mode. This is described in rev 2 of the ds2408's datasheet
+ * (http://datasheets.maximintegrated.com/en/ds/DS2408.pdf) under
+ * "APPLICATION INFORMATION/Power-up timing".
+ */
+static int w1_f29_disable_test_mode(struct w1_slave *sl)
+{
+	int res;
+	u8 magic[10] = {0x96, };
+	u64 rn = le64_to_cpu(*((u64*)&sl->reg_num));
+
+	memcpy(&magic[1], &rn, 8);
+	magic[9] = 0x3C;
+
+	mutex_lock(&sl->master->bus_mutex);
+
+	res = w1_reset_bus(sl->master);
+	if (res)
+		goto out;
+	w1_write_block(sl->master, magic, ARRAY_SIZE(magic));
+
+	res = w1_reset_bus(sl->master);
+out:
+	mutex_unlock(&sl->master->bus_mutex);
+	return res;
+}
+
+static BIN_ATTR_RO(state, 1);
+static BIN_ATTR_RW(output, 1);
+static BIN_ATTR_RW(activity, 1);
+static BIN_ATTR_RO(cond_search_mask, 1);
+static BIN_ATTR_RO(cond_search_polarity, 1);
+static BIN_ATTR_RW(status_control, 1);
+
+static struct bin_attribute *w1_f29_bin_attrs[] = {
+	&bin_attr_state,
+	&bin_attr_output,
+	&bin_attr_activity,
+	&bin_attr_cond_search_mask,
+	&bin_attr_cond_search_polarity,
+	&bin_attr_status_control,
+	NULL,
+};
+
+static const struct attribute_group w1_f29_group = {
+	.bin_attrs = w1_f29_bin_attrs,
+};
+
+static const struct attribute_group *w1_f29_groups[] = {
+	&w1_f29_group,
+	NULL,
+};
+
+static const struct w1_family_ops w1_f29_fops = {
+	.add_slave      = w1_f29_disable_test_mode,
+	.groups		= w1_f29_groups,
+};
+
+static struct w1_family w1_family_29 = {
+	.fid = W1_FAMILY_DS2408,
+	.fops = &w1_f29_fops,
+};
+module_w1_family(w1_family_29);
+
+MODULE_AUTHOR("Jean-Francois Dagenais <dagenaisj@sonatest.com>");
+MODULE_DESCRIPTION("w1 family 29 driver for DS2408 8 Pin IO");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("w1-family-" __stringify(W1_FAMILY_DS2408));