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-rw-r--r--target/linux/brcm2708/patches-4.1/0119-Merge-pull-request-1059-from-pelwell-rpi-4.0.y.patch298
1 files changed, 298 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.1/0119-Merge-pull-request-1059-from-pelwell-rpi-4.0.y.patch b/target/linux/brcm2708/patches-4.1/0119-Merge-pull-request-1059-from-pelwell-rpi-4.0.y.patch
new file mode 100644
index 0000000000..6280f75a48
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.1/0119-Merge-pull-request-1059-from-pelwell-rpi-4.0.y.patch
@@ -0,0 +1,298 @@
+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)