You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
298 lines
8.8 KiB
298 lines
8.8 KiB
From 0dd4dae3071d135836946ab1b990061c0899e9b5 Mon Sep 17 00:00:00 2001
|
|
From: Phil Elwell <pelwell@users.noreply.github.com>
|
|
Date: Mon, 13 Jul 2015 13:25:31 +0100
|
|
Subject: [PATCH 119/121] Merge pull request #1059 from pelwell/rpi-4.0.y
|
|
|
|
w1_therm: Back-port locking improvements from 4.2-rc1
|
|
---
|
|
Documentation/ABI/stable/sysfs-driver-w1_ds28ea00 | 6 +
|
|
Documentation/w1/slaves/w1_therm | 11 +-
|
|
drivers/w1/slaves/w1_therm.c | 162 ++++++++++++++++++++--
|
|
3 files changed, 163 insertions(+), 16 deletions(-)
|
|
create mode 100644 Documentation/ABI/stable/sysfs-driver-w1_ds28ea00
|
|
|
|
--- /dev/null
|
|
+++ b/Documentation/ABI/stable/sysfs-driver-w1_ds28ea00
|
|
@@ -0,0 +1,6 @@
|
|
+What: /sys/bus/w1/devices/.../w1_seq
|
|
+Date: Apr 2015
|
|
+Contact: Matt Campbell <mattrcampbell@gmail.com>
|
|
+Description: Support for the DS28EA00 chain sequence function
|
|
+ see Documentation/w1/slaves/w1_therm for detailed information
|
|
+Users: any user space application which wants to communicate with DS28EA00
|
|
--- a/Documentation/w1/slaves/w1_therm
|
|
+++ b/Documentation/w1/slaves/w1_therm
|
|
@@ -11,12 +11,14 @@ Author: Evgeniy Polyakov <johnpol@2ka.mi
|
|
Description
|
|
-----------
|
|
|
|
-w1_therm provides basic temperature conversion for ds18*20 devices.
|
|
+w1_therm provides basic temperature conversion for ds18*20 devices, and the
|
|
+ds28ea00 device.
|
|
supported family codes:
|
|
W1_THERM_DS18S20 0x10
|
|
W1_THERM_DS1822 0x22
|
|
W1_THERM_DS18B20 0x28
|
|
W1_THERM_DS1825 0x3B
|
|
+W1_THERM_DS28EA00 0x42
|
|
|
|
Support is provided through the sysfs w1_slave file. Each open and
|
|
read sequence will initiate a temperature conversion then provide two
|
|
@@ -48,3 +50,10 @@ resistor). The DS18b20 temperature sens
|
|
maximum current draw of 1.5mA and that a 5k pullup resistor is not
|
|
sufficient. The strong pullup is designed to provide the additional
|
|
current required.
|
|
+
|
|
+The DS28EA00 provides an additional two pins for implementing a sequence
|
|
+detection algorithm. This feature allows you to determine the physical
|
|
+location of the chip in the 1-wire bus without needing pre-existing
|
|
+knowledge of the bus ordering. Support is provided through the sysfs
|
|
+w1_seq file. The file will contain a single line with an integer value
|
|
+representing the device index in the bus starting at 0.
|
|
--- a/drivers/w1/slaves/w1_therm.c
|
|
+++ b/drivers/w1/slaves/w1_therm.c
|
|
@@ -59,16 +59,32 @@ MODULE_ALIAS("w1-family-" __stringify(W1
|
|
static int w1_strong_pullup = 1;
|
|
module_param_named(strong_pullup, w1_strong_pullup, int, 0);
|
|
|
|
+struct w1_therm_family_data {
|
|
+ uint8_t rom[9];
|
|
+ atomic_t refcnt;
|
|
+};
|
|
+
|
|
+/* return the address of the refcnt in the family data */
|
|
+#define THERM_REFCNT(family_data) \
|
|
+ (&((struct w1_therm_family_data*)family_data)->refcnt)
|
|
+
|
|
static int w1_therm_add_slave(struct w1_slave *sl)
|
|
{
|
|
- sl->family_data = kzalloc(9, GFP_KERNEL);
|
|
+ sl->family_data = kzalloc(sizeof(struct w1_therm_family_data),
|
|
+ GFP_KERNEL);
|
|
if (!sl->family_data)
|
|
return -ENOMEM;
|
|
+ atomic_set(THERM_REFCNT(sl->family_data), 1);
|
|
return 0;
|
|
}
|
|
|
|
static void w1_therm_remove_slave(struct w1_slave *sl)
|
|
{
|
|
+ int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data));
|
|
+ while(refcnt) {
|
|
+ msleep(1000);
|
|
+ refcnt = atomic_read(THERM_REFCNT(sl->family_data));
|
|
+ }
|
|
kfree(sl->family_data);
|
|
sl->family_data = NULL;
|
|
}
|
|
@@ -76,13 +92,24 @@ static void w1_therm_remove_slave(struct
|
|
static ssize_t w1_slave_show(struct device *device,
|
|
struct device_attribute *attr, char *buf);
|
|
|
|
+static ssize_t w1_seq_show(struct device *device,
|
|
+ struct device_attribute *attr, char *buf);
|
|
+
|
|
static DEVICE_ATTR_RO(w1_slave);
|
|
+static DEVICE_ATTR_RO(w1_seq);
|
|
|
|
static struct attribute *w1_therm_attrs[] = {
|
|
&dev_attr_w1_slave.attr,
|
|
NULL,
|
|
};
|
|
+
|
|
+static struct attribute *w1_ds28ea00_attrs[] = {
|
|
+ &dev_attr_w1_slave.attr,
|
|
+ &dev_attr_w1_seq.attr,
|
|
+ NULL,
|
|
+};
|
|
ATTRIBUTE_GROUPS(w1_therm);
|
|
+ATTRIBUTE_GROUPS(w1_ds28ea00);
|
|
|
|
static struct w1_family_ops w1_therm_fops = {
|
|
.add_slave = w1_therm_add_slave,
|
|
@@ -90,6 +117,12 @@ static struct w1_family_ops w1_therm_fop
|
|
.groups = w1_therm_groups,
|
|
};
|
|
|
|
+static struct w1_family_ops w1_ds28ea00_fops = {
|
|
+ .add_slave = w1_therm_add_slave,
|
|
+ .remove_slave = w1_therm_remove_slave,
|
|
+ .groups = w1_ds28ea00_groups,
|
|
+};
|
|
+
|
|
static struct w1_family w1_therm_family_DS18S20 = {
|
|
.fid = W1_THERM_DS18S20,
|
|
.fops = &w1_therm_fops,
|
|
@@ -107,7 +140,7 @@ static struct w1_family w1_therm_family_
|
|
|
|
static struct w1_family w1_therm_family_DS28EA00 = {
|
|
.fid = W1_THERM_DS28EA00,
|
|
- .fops = &w1_therm_fops,
|
|
+ .fops = &w1_ds28ea00_fops,
|
|
};
|
|
|
|
static struct w1_family w1_therm_family_DS1825 = {
|
|
@@ -194,13 +227,22 @@ static ssize_t w1_slave_show(struct devi
|
|
struct w1_slave *sl = dev_to_w1_slave(device);
|
|
struct w1_master *dev = sl->master;
|
|
u8 rom[9], crc, verdict, external_power;
|
|
- int i, max_trying = 10;
|
|
+ int i, ret, max_trying = 10;
|
|
ssize_t c = PAGE_SIZE;
|
|
+ u8 *family_data = sl->family_data;
|
|
|
|
- i = mutex_lock_interruptible(&dev->bus_mutex);
|
|
- if (i != 0)
|
|
- return i;
|
|
+ ret = mutex_lock_interruptible(&dev->bus_mutex);
|
|
+ if (ret != 0)
|
|
+ goto post_unlock;
|
|
+
|
|
+ if(!sl->family_data)
|
|
+ {
|
|
+ ret = -ENODEV;
|
|
+ goto pre_unlock;
|
|
+ }
|
|
|
|
+ /* prevent the slave from going away in sleep */
|
|
+ atomic_inc(THERM_REFCNT(family_data));
|
|
memset(rom, 0, sizeof(rom));
|
|
|
|
while (max_trying--) {
|
|
@@ -230,17 +272,19 @@ static ssize_t w1_slave_show(struct devi
|
|
mutex_unlock(&dev->bus_mutex);
|
|
|
|
sleep_rem = msleep_interruptible(tm);
|
|
- if (sleep_rem != 0)
|
|
- return -EINTR;
|
|
+ if (sleep_rem != 0) {
|
|
+ ret = -EINTR;
|
|
+ goto post_unlock;
|
|
+ }
|
|
|
|
- i = mutex_lock_interruptible(&dev->bus_mutex);
|
|
- if (i != 0)
|
|
- return i;
|
|
+ ret = mutex_lock_interruptible(&dev->bus_mutex);
|
|
+ if (ret != 0)
|
|
+ goto post_unlock;
|
|
} else if (!w1_strong_pullup) {
|
|
sleep_rem = msleep_interruptible(tm);
|
|
if (sleep_rem != 0) {
|
|
- mutex_unlock(&dev->bus_mutex);
|
|
- return -EINTR;
|
|
+ ret = -EINTR;
|
|
+ goto pre_unlock;
|
|
}
|
|
}
|
|
|
|
@@ -269,19 +313,107 @@ static ssize_t w1_slave_show(struct devi
|
|
c -= snprintf(buf + PAGE_SIZE - c, c, ": crc=%02x %s\n",
|
|
crc, (verdict) ? "YES" : "NO");
|
|
if (verdict)
|
|
- memcpy(sl->family_data, rom, sizeof(rom));
|
|
+ memcpy(family_data, rom, sizeof(rom));
|
|
else
|
|
dev_warn(device, "Read failed CRC check\n");
|
|
|
|
for (i = 0; i < 9; ++i)
|
|
c -= snprintf(buf + PAGE_SIZE - c, c, "%02x ",
|
|
- ((u8 *)sl->family_data)[i]);
|
|
+ ((u8 *)family_data)[i]);
|
|
|
|
c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n",
|
|
w1_convert_temp(rom, sl->family->fid));
|
|
+ ret = PAGE_SIZE - c;
|
|
+
|
|
+pre_unlock:
|
|
mutex_unlock(&dev->bus_mutex);
|
|
|
|
+post_unlock:
|
|
+ atomic_dec(THERM_REFCNT(family_data));
|
|
+ return ret;
|
|
+}
|
|
+
|
|
+#define W1_42_CHAIN 0x99
|
|
+#define W1_42_CHAIN_OFF 0x3C
|
|
+#define W1_42_CHAIN_OFF_INV 0xC3
|
|
+#define W1_42_CHAIN_ON 0x5A
|
|
+#define W1_42_CHAIN_ON_INV 0xA5
|
|
+#define W1_42_CHAIN_DONE 0x96
|
|
+#define W1_42_CHAIN_DONE_INV 0x69
|
|
+#define W1_42_COND_READ 0x0F
|
|
+#define W1_42_SUCCESS_CONFIRM_BYTE 0xAA
|
|
+#define W1_42_FINISHED_BYTE 0xFF
|
|
+static ssize_t w1_seq_show(struct device *device,
|
|
+ struct device_attribute *attr, char *buf)
|
|
+{
|
|
+ struct w1_slave *sl = dev_to_w1_slave(device);
|
|
+ ssize_t c = PAGE_SIZE;
|
|
+ int rv;
|
|
+ int i;
|
|
+ u8 ack;
|
|
+ u64 rn;
|
|
+ struct w1_reg_num *reg_num;
|
|
+ int seq = 0;
|
|
+
|
|
+ mutex_lock(&sl->master->bus_mutex);
|
|
+ /* Place all devices in CHAIN state */
|
|
+ if (w1_reset_bus(sl->master))
|
|
+ goto error;
|
|
+ w1_write_8(sl->master, W1_SKIP_ROM);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN_ON);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN_ON_INV);
|
|
+ msleep(sl->master->pullup_duration);
|
|
+
|
|
+ /* check for acknowledgment */
|
|
+ ack = w1_read_8(sl->master);
|
|
+ if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
|
|
+ goto error;
|
|
+
|
|
+ /* In case the bus fails to send 0xFF, limit*/
|
|
+ for (i = 0; i <= 64; i++) {
|
|
+ if (w1_reset_bus(sl->master))
|
|
+ goto error;
|
|
+
|
|
+ w1_write_8(sl->master, W1_42_COND_READ);
|
|
+ rv = w1_read_block(sl->master, (u8 *)&rn, 8);
|
|
+ reg_num = (struct w1_reg_num *) &rn;
|
|
+ if (reg_num->family == W1_42_FINISHED_BYTE)
|
|
+ break;
|
|
+ if (sl->reg_num.id == reg_num->id)
|
|
+ seq = i;
|
|
+
|
|
+ w1_write_8(sl->master, W1_42_CHAIN);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN_DONE);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN_DONE_INV);
|
|
+ w1_read_block(sl->master, &ack, sizeof(ack));
|
|
+
|
|
+ /* check for acknowledgment */
|
|
+ ack = w1_read_8(sl->master);
|
|
+ if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
|
|
+ goto error;
|
|
+
|
|
+ }
|
|
+
|
|
+ /* Exit from CHAIN state */
|
|
+ if (w1_reset_bus(sl->master))
|
|
+ goto error;
|
|
+ w1_write_8(sl->master, W1_SKIP_ROM);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN_OFF);
|
|
+ w1_write_8(sl->master, W1_42_CHAIN_OFF_INV);
|
|
+
|
|
+ /* check for acknowledgment */
|
|
+ ack = w1_read_8(sl->master);
|
|
+ if (ack != W1_42_SUCCESS_CONFIRM_BYTE)
|
|
+ goto error;
|
|
+ mutex_unlock(&sl->master->bus_mutex);
|
|
+
|
|
+ c -= snprintf(buf + PAGE_SIZE - c, c, "%d\n", seq);
|
|
return PAGE_SIZE - c;
|
|
+error:
|
|
+ mutex_unlock(&sl->master->bus_mutex);
|
|
+ return -EIO;
|
|
}
|
|
|
|
static int __init w1_therm_init(void)
|
|
|