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Diffstat (limited to 'drivers/w1/slaves/w1_ds2438.c')
-rw-r--r--drivers/w1/slaves/w1_ds2438.c215
1 files changed, 170 insertions, 45 deletions
diff --git a/drivers/w1/slaves/w1_ds2438.c b/drivers/w1/slaves/w1_ds2438.c
index 6487fb772a20..86860f727e96 100644
--- a/drivers/w1/slaves/w1_ds2438.c
+++ b/drivers/w1/slaves/w1_ds2438.c
@@ -1,10 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* 1-Wire implementation for the ds2438 chip
*
* Copyright (c) 2017 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>
@@ -51,7 +49,16 @@
#define DS2438_CURRENT_MSB 0x06
#define DS2438_THRESHOLD 0x07
-int w1_ds2438_get_page(struct w1_slave *sl, int pageno, u8 *buf)
+/* Page #1 definitions */
+#define DS2438_ETM_0 0x00
+#define DS2438_ETM_1 0x01
+#define DS2438_ETM_2 0x02
+#define DS2438_ETM_3 0x03
+#define DS2438_ICA 0x04
+#define DS2438_OFFSET_LSB 0x05
+#define DS2438_OFFSET_MSB 0x06
+
+static int w1_ds2438_get_page(struct w1_slave *sl, int pageno, u8 *buf)
{
unsigned int retries = W1_DS2438_RETRIES;
u8 w1_buf[2];
@@ -59,18 +66,16 @@ int w1_ds2438_get_page(struct w1_slave *sl, int pageno, u8 *buf)
size_t count;
while (retries--) {
- crc = 0;
-
if (w1_reset_select_slave(sl))
continue;
w1_buf[0] = W1_DS2438_RECALL_MEMORY;
- w1_buf[1] = 0x00;
+ w1_buf[1] = (u8)pageno;
w1_write_block(sl->master, w1_buf, 2);
if (w1_reset_select_slave(sl))
continue;
w1_buf[0] = W1_DS2438_READ_SCRATCH;
- w1_buf[1] = 0x00;
+ w1_buf[1] = (u8)pageno;
w1_write_block(sl->master, w1_buf, 2);
count = w1_read_block(sl->master, buf, DS2438_PAGE_SIZE + 1);
@@ -85,7 +90,7 @@ int w1_ds2438_get_page(struct w1_slave *sl, int pageno, u8 *buf)
return -1;
}
-int w1_ds2438_get_temperature(struct w1_slave *sl, int16_t *temperature)
+static int w1_ds2438_get_temperature(struct w1_slave *sl, int16_t *temperature)
{
unsigned int retries = W1_DS2438_RETRIES;
u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
@@ -127,7 +132,7 @@ post_unlock:
return ret;
}
-int w1_ds2438_change_config_bit(struct w1_slave *sl, u8 mask, u8 value)
+static int w1_ds2438_change_config_bit(struct w1_slave *sl, u8 mask, u8 value)
{
unsigned int retries = W1_DS2438_RETRIES;
u8 w1_buf[3];
@@ -156,11 +161,11 @@ int w1_ds2438_change_config_bit(struct w1_slave *sl, u8 mask, u8 value)
if ((status & mask) == value)
return 0; /* already set as requested */
- else {
- /* changing bit */
- status ^= mask;
- perform_write = 1;
- }
+
+ /* changing bit */
+ status ^= mask;
+ perform_write = 1;
+
break;
}
@@ -186,7 +191,36 @@ int w1_ds2438_change_config_bit(struct w1_slave *sl, u8 mask, u8 value)
return -1;
}
-uint16_t w1_ds2438_get_voltage(struct w1_slave *sl, int adc_input, uint16_t *voltage)
+static int w1_ds2438_change_offset_register(struct w1_slave *sl, u8 *value)
+{
+ unsigned int retries = W1_DS2438_RETRIES;
+ u8 w1_buf[9];
+ u8 w1_page1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+
+ if (w1_ds2438_get_page(sl, 1, w1_page1_buf) == 0) {
+ memcpy(&w1_buf[2], w1_page1_buf, DS2438_PAGE_SIZE - 1); /* last register reserved */
+ w1_buf[7] = value[0]; /* change only offset register */
+ w1_buf[8] = value[1];
+ while (retries--) {
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_WRITE_SCRATCH;
+ w1_buf[1] = 0x01; /* write to page 1 */
+ w1_write_block(sl->master, w1_buf, 9);
+
+ if (w1_reset_select_slave(sl))
+ continue;
+ w1_buf[0] = W1_DS2438_COPY_SCRATCH;
+ w1_buf[1] = 0x01;
+ w1_write_block(sl->master, w1_buf, 2);
+ return 0;
+ }
+ }
+ return -1;
+}
+
+static int w1_ds2438_get_voltage(struct w1_slave *sl,
+ int adc_input, uint16_t *voltage)
{
unsigned int retries = W1_DS2438_RETRIES;
u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
@@ -234,8 +268,27 @@ post_unlock:
return ret;
}
+static int w1_ds2438_get_current(struct w1_slave *sl, int16_t *voltage)
+{
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+ int ret;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) {
+ /* The voltage measured across current sense resistor RSENS. */
+ *voltage = (((int16_t) w1_buf[DS2438_CURRENT_MSB]) << 8) | ((int16_t) w1_buf[DS2438_CURRENT_LSB]);
+ ret = 0;
+ } else
+ ret = -1;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
static ssize_t iad_write(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr, char *buf,
+ const struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct w1_slave *sl = kobj_to_w1_slave(kobj);
@@ -256,8 +309,29 @@ static ssize_t iad_write(struct file *filp, struct kobject *kobj,
return ret;
}
+static ssize_t iad_read(struct file *filp, struct kobject *kobj,
+ const struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ int16_t voltage;
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ if (w1_ds2438_get_current(sl, &voltage) == 0)
+ ret = snprintf(buf, count, "%i\n", voltage);
+ else
+ ret = -EIO;
+
+ return ret;
+}
+
static ssize_t page0_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr, char *buf,
+ const struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct w1_slave *sl = kobj_to_w1_slave(kobj);
@@ -271,9 +345,43 @@ static ssize_t page0_read(struct file *filp, struct kobject *kobj,
mutex_lock(&sl->master->bus_mutex);
+ /* Read no more than page0 size */
+ if (count > DS2438_PAGE_SIZE)
+ count = DS2438_PAGE_SIZE;
+
if (w1_ds2438_get_page(sl, 0, w1_buf) == 0) {
- memcpy(buf, &w1_buf, DS2438_PAGE_SIZE);
- ret = DS2438_PAGE_SIZE;
+ memcpy(buf, &w1_buf, count);
+ ret = count;
+ } else
+ ret = -EIO;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
+static ssize_t page1_read(struct file *filp, struct kobject *kobj,
+ const struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+ u8 w1_buf[DS2438_PAGE_SIZE + 1 /*for CRC*/];
+
+ if (off != 0)
+ return 0;
+ if (!buf)
+ return -EINVAL;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ /* Read no more than page1 size */
+ if (count > DS2438_PAGE_SIZE)
+ count = DS2438_PAGE_SIZE;
+
+ if (w1_ds2438_get_page(sl, 1, w1_buf) == 0) {
+ memcpy(buf, &w1_buf, count);
+ ret = count;
} else
ret = -EIO;
@@ -282,13 +390,31 @@ static ssize_t page0_read(struct file *filp, struct kobject *kobj,
return ret;
}
+static ssize_t offset_write(struct file *filp, struct kobject *kobj,
+ const struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct w1_slave *sl = kobj_to_w1_slave(kobj);
+ int ret;
+
+ mutex_lock(&sl->master->bus_mutex);
+
+ if (w1_ds2438_change_offset_register(sl, buf) == 0)
+ ret = count;
+ else
+ ret = -EIO;
+
+ mutex_unlock(&sl->master->bus_mutex);
+
+ return ret;
+}
+
static ssize_t temperature_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr, char *buf,
+ const struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct w1_slave *sl = kobj_to_w1_slave(kobj);
int ret;
- ssize_t c = PAGE_SIZE;
int16_t temp;
if (off != 0)
@@ -296,22 +422,20 @@ static ssize_t temperature_read(struct file *filp, struct kobject *kobj,
if (!buf)
return -EINVAL;
- if (w1_ds2438_get_temperature(sl, &temp) == 0) {
- c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", temp);
- ret = PAGE_SIZE - c;
- } else
+ if (w1_ds2438_get_temperature(sl, &temp) == 0)
+ ret = snprintf(buf, count, "%i\n", temp);
+ else
ret = -EIO;
return ret;
}
static ssize_t vad_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr, char *buf,
+ const struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct w1_slave *sl = kobj_to_w1_slave(kobj);
int ret;
- ssize_t c = PAGE_SIZE;
uint16_t voltage;
if (off != 0)
@@ -319,22 +443,20 @@ static ssize_t vad_read(struct file *filp, struct kobject *kobj,
if (!buf)
return -EINVAL;
- if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VAD, &voltage) == 0) {
- c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", voltage);
- ret = PAGE_SIZE - c;
- } else
+ if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VAD, &voltage) == 0)
+ ret = snprintf(buf, count, "%u\n", voltage);
+ else
ret = -EIO;
return ret;
}
static ssize_t vdd_read(struct file *filp, struct kobject *kobj,
- struct bin_attribute *bin_attr, char *buf,
+ const struct bin_attribute *bin_attr, char *buf,
loff_t off, size_t count)
{
struct w1_slave *sl = kobj_to_w1_slave(kobj);
int ret;
- ssize_t c = PAGE_SIZE;
uint16_t voltage;
if (off != 0)
@@ -342,24 +464,27 @@ static ssize_t vdd_read(struct file *filp, struct kobject *kobj,
if (!buf)
return -EINVAL;
- if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VDD, &voltage) == 0) {
- c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", voltage);
- ret = PAGE_SIZE - c;
- } else
+ if (w1_ds2438_get_voltage(sl, DS2438_ADC_INPUT_VDD, &voltage) == 0)
+ ret = snprintf(buf, count, "%u\n", voltage);
+ else
ret = -EIO;
return ret;
}
-static BIN_ATTR(iad, S_IRUGO | S_IWUSR | S_IWGRP, NULL, iad_write, 1);
-static BIN_ATTR_RO(page0, DS2438_PAGE_SIZE);
-static BIN_ATTR_RO(temperature, 0/* real length varies */);
-static BIN_ATTR_RO(vad, 0/* real length varies */);
-static BIN_ATTR_RO(vdd, 0/* real length varies */);
+static const BIN_ATTR_RW(iad, 0);
+static const BIN_ATTR_RO(page0, DS2438_PAGE_SIZE);
+static const BIN_ATTR_RO(page1, DS2438_PAGE_SIZE);
+static const BIN_ATTR_WO(offset, 2);
+static const BIN_ATTR_RO(temperature, 0/* real length varies */);
+static const BIN_ATTR_RO(vad, 0/* real length varies */);
+static const BIN_ATTR_RO(vdd, 0/* real length varies */);
-static struct bin_attribute *w1_ds2438_bin_attrs[] = {
+static const struct bin_attribute *const w1_ds2438_bin_attrs[] = {
&bin_attr_iad,
&bin_attr_page0,
+ &bin_attr_page1,
+ &bin_attr_offset,
&bin_attr_temperature,
&bin_attr_vad,
&bin_attr_vdd,
@@ -375,7 +500,7 @@ static const struct attribute_group *w1_ds2438_groups[] = {
NULL,
};
-static struct w1_family_ops w1_ds2438_fops = {
+static const struct w1_family_ops w1_ds2438_fops = {
.groups = w1_ds2438_groups,
};
generated by cgit (git 2.34.1) at 2025-12-28 09:21:26 +0000