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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-26 11:25:33 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-26 11:25:33 -0700
commitfa93669a1917f93b09142d4b2298329b82d7d36d (patch)
tree7f8d6dc9d1fbb086c59a799a3a7137c46fb9959e /drivers/w1
parentb13bc8dda81c54a66a1c84e66f60b8feba659f28 (diff)
parent6791457a090d9a234a40b501c2536f0aefaeae4b (diff)
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Merge tag 'driver-core-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core changes from Greg Kroah-Hartman: "Here's the big driver core pull request for 3.6-rc1. Unlike 3.5, this kernel should be a lot tamer, with the printk changes now settled down. All we have here is some extcon driver updates, w1 driver updates, a few printk cleanups that weren't needed for 3.5, but are good to have now, and some other minor fixes/changes in the driver core. All of these have been in the linux-next releases for a while now. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" * tag 'driver-core-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (38 commits) printk: Export struct log size and member offsets through vmcoreinfo Drivers: hv: Change the hex constant to a decimal constant driver core: don't trigger uevent after failure extcon: MAX77693: Add extcon-max77693 driver to support Maxim MAX77693 MUIC device sysfs: fail dentry revalidation after namespace change fix sysfs: fail dentry revalidation after namespace change extcon: spelling of detach in function doc extcon: arizona: Stop microphone detection if we give up on it extcon: arizona: Update cable reporting calls and split headset PM / Runtime: Do not increment device usage counts before probing kmsg - do not flush partial lines when the console is busy kmsg - export "continuation record" flag to /dev/kmsg kmsg - avoid warning for CONFIG_PRINTK=n compilations kmsg - properly print over-long continuation lines driver-core: Use kobj_to_dev instead of re-implementing it driver-core: Move kobj_to_dev from genhd.h to device.h driver core: Move deferred devices to the end of dpm_list before probing driver core: move uevent call to driver_register driver core: fix shutdown races with probe/remove(v3) Extcon: Arizona: Add driver for Wolfson Arizona class devices ...
Diffstat (limited to 'drivers/w1')
-rw-r--r--drivers/w1/masters/ds1wm.c4
-rw-r--r--drivers/w1/masters/omap_hdq.c30
-rw-r--r--drivers/w1/slaves/Kconfig13
-rw-r--r--drivers/w1/slaves/Makefile1
-rw-r--r--drivers/w1/slaves/w1_bq27000.c4
-rw-r--r--drivers/w1/slaves/w1_ds2408.c24
-rw-r--r--drivers/w1/slaves/w1_ds2423.c4
-rw-r--r--drivers/w1/slaves/w1_ds2431.c8
-rw-r--r--drivers/w1/slaves/w1_ds2433.c8
-rw-r--r--drivers/w1/slaves/w1_ds2760.c8
-rw-r--r--drivers/w1/slaves/w1_ds2780.c22
-rw-r--r--drivers/w1/slaves/w1_ds2780.h2
-rw-r--r--drivers/w1/slaves/w1_ds2781.c22
-rw-r--r--drivers/w1/slaves/w1_ds2781.h2
-rw-r--r--drivers/w1/slaves/w1_ds28e04.c469
-rw-r--r--drivers/w1/slaves/w1_therm.c10
-rw-r--r--drivers/w1/w1.c23
-rw-r--r--drivers/w1/w1.h1
-rw-r--r--drivers/w1/w1_family.h1
-rw-r--r--drivers/w1/w1_int.c3
20 files changed, 560 insertions, 99 deletions
diff --git a/drivers/w1/masters/ds1wm.c b/drivers/w1/masters/ds1wm.c
index a0c8965c1a79..530a2d309063 100644
--- a/drivers/w1/masters/ds1wm.c
+++ b/drivers/w1/masters/ds1wm.c
@@ -334,7 +334,9 @@ static void ds1wm_search(void *data, struct w1_master *master_dev,
return;
}
+ mutex_lock(&master_dev->bus_mutex);
if (ds1wm_reset(ds1wm_data)) {
+ mutex_unlock(&master_dev->bus_mutex);
dev_dbg(&ds1wm_data->pdev->dev,
"pass: %d reset error (or no slaves)\n", pass);
break;
@@ -387,6 +389,7 @@ static void ds1wm_search(void *data, struct w1_master *master_dev,
}
if (ds1wm_data->read_error) {
+ mutex_unlock(&master_dev->bus_mutex);
dev_err(&ds1wm_data->pdev->dev,
"pass: %d read error, retrying\n", pass);
break;
@@ -400,6 +403,7 @@ static void ds1wm_search(void *data, struct w1_master *master_dev,
dev_dbg(&ds1wm_data->pdev->dev,
"pass: %d resetting bus\n", pass);
ds1wm_reset(ds1wm_data);
+ mutex_unlock(&master_dev->bus_mutex);
if ((r_prime & ((u64)1 << 63)) && (d & ((u64)1 << 63))) {
dev_err(&ds1wm_data->pdev->dev,
"pass: %d bus error, retrying\n", pass);
diff --git a/drivers/w1/masters/omap_hdq.c b/drivers/w1/masters/omap_hdq.c
index 291897c881be..4b0fcf3c2d03 100644
--- a/drivers/w1/masters/omap_hdq.c
+++ b/drivers/w1/masters/omap_hdq.c
@@ -178,6 +178,7 @@ static int hdq_write_byte(struct hdq_data *hdq_data, u8 val, u8 *status)
hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
if (ret == 0) {
dev_dbg(hdq_data->dev, "TX wait elapsed\n");
+ ret = -ETIMEDOUT;
goto out;
}
@@ -185,7 +186,7 @@ static int hdq_write_byte(struct hdq_data *hdq_data, u8 val, u8 *status)
/* check irqstatus */
if (!(*status & OMAP_HDQ_INT_STATUS_TXCOMPLETE)) {
dev_dbg(hdq_data->dev, "timeout waiting for"
- "TXCOMPLETE/RXCOMPLETE, %x", *status);
+ " TXCOMPLETE/RXCOMPLETE, %x", *status);
ret = -ETIMEDOUT;
goto out;
}
@@ -196,7 +197,7 @@ static int hdq_write_byte(struct hdq_data *hdq_data, u8 val, u8 *status)
OMAP_HDQ_FLAG_CLEAR, &tmp_status);
if (ret) {
dev_dbg(hdq_data->dev, "timeout waiting GO bit"
- "return to zero, %x", tmp_status);
+ " return to zero, %x", tmp_status);
}
out:
@@ -339,7 +340,7 @@ static int omap_hdq_break(struct hdq_data *hdq_data)
&tmp_status);
if (ret)
dev_dbg(hdq_data->dev, "timeout waiting INIT&GO bits"
- "return to zero, %x", tmp_status);
+ " return to zero, %x", tmp_status);
out:
mutex_unlock(&hdq_data->hdq_mutex);
@@ -351,7 +352,6 @@ static int hdq_read_byte(struct hdq_data *hdq_data, u8 *val)
{
int ret = 0;
u8 status;
- unsigned long timeout = jiffies + OMAP_HDQ_TIMEOUT;
ret = mutex_lock_interruptible(&hdq_data->hdq_mutex);
if (ret < 0) {
@@ -369,22 +369,20 @@ static int hdq_read_byte(struct hdq_data *hdq_data, u8 *val)
OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO,
OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
/*
- * The RX comes immediately after TX. It
- * triggers another interrupt before we
- * sleep. So we have to wait for RXCOMPLETE bit.
+ * The RX comes immediately after TX.
*/
- while (!(hdq_data->hdq_irqstatus
- & OMAP_HDQ_INT_STATUS_RXCOMPLETE)
- && time_before(jiffies, timeout)) {
- schedule_timeout_uninterruptible(1);
- }
+ wait_event_timeout(hdq_wait_queue,
+ (hdq_data->hdq_irqstatus
+ & OMAP_HDQ_INT_STATUS_RXCOMPLETE),
+ OMAP_HDQ_TIMEOUT);
+
hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, 0,
OMAP_HDQ_CTRL_STATUS_DIR);
status = hdq_data->hdq_irqstatus;
/* check irqstatus */
if (!(status & OMAP_HDQ_INT_STATUS_RXCOMPLETE)) {
dev_dbg(hdq_data->dev, "timeout waiting for"
- "RXCOMPLETE, %x", status);
+ " RXCOMPLETE, %x", status);
ret = -ETIMEDOUT;
goto out;
}
@@ -394,7 +392,7 @@ static int hdq_read_byte(struct hdq_data *hdq_data, u8 *val)
out:
mutex_unlock(&hdq_data->hdq_mutex);
rtn:
- return 0;
+ return ret;
}
@@ -456,7 +454,7 @@ static int omap_hdq_put(struct hdq_data *hdq_data)
if (0 == hdq_data->hdq_usecount) {
dev_dbg(hdq_data->dev, "attempt to decrement use count"
- "when it is zero");
+ " when it is zero");
ret = -EINVAL;
} else {
hdq_data->hdq_usecount--;
@@ -524,7 +522,7 @@ static void omap_w1_write_byte(void *_hdq, u8 byte)
mutex_unlock(&hdq_data->hdq_mutex);
ret = hdq_write_byte(hdq_data, byte, &status);
- if (ret == 0) {
+ if (ret < 0) {
dev_dbg(hdq_data->dev, "TX failure:Ctrl status %x\n", status);
return;
}
diff --git a/drivers/w1/slaves/Kconfig b/drivers/w1/slaves/Kconfig
index eb9e376d6244..67526690acbc 100644
--- a/drivers/w1/slaves/Kconfig
+++ b/drivers/w1/slaves/Kconfig
@@ -94,6 +94,19 @@ config W1_SLAVE_DS2781
If you are unsure, say N.
+config W1_SLAVE_DS28E04
+ tristate "4096-Bit Addressable 1-Wire EEPROM with PIO (DS28E04-100)"
+ depends on W1
+ select CRC16
+ help
+ If you enable this you will have the DS28E04-100
+ chip support.
+
+ Say Y here if you want to use a 1-wire
+ 4kb EEPROM with PIO family device (DS28E04).
+
+ If you are unsure, say N.
+
config W1_SLAVE_BQ27000
tristate "BQ27000 slave support"
depends on W1
diff --git a/drivers/w1/slaves/Makefile b/drivers/w1/slaves/Makefile
index c4f1859fb520..05188f6aab5a 100644
--- a/drivers/w1/slaves/Makefile
+++ b/drivers/w1/slaves/Makefile
@@ -12,3 +12,4 @@ obj-$(CONFIG_W1_SLAVE_DS2760) += w1_ds2760.o
obj-$(CONFIG_W1_SLAVE_DS2780) += w1_ds2780.o
obj-$(CONFIG_W1_SLAVE_DS2781) += w1_ds2781.o
obj-$(CONFIG_W1_SLAVE_BQ27000) += w1_bq27000.o
+obj-$(CONFIG_W1_SLAVE_DS28E04) += w1_ds28e04.o
diff --git a/drivers/w1/slaves/w1_bq27000.c b/drivers/w1/slaves/w1_bq27000.c
index 52ad812fa1e7..773dca5beafe 100644
--- a/drivers/w1/slaves/w1_bq27000.c
+++ b/drivers/w1/slaves/w1_bq27000.c
@@ -31,10 +31,10 @@ static int w1_bq27000_read(struct device *dev, unsigned int reg)
u8 val;
struct w1_slave *sl = container_of(dev->parent, struct w1_slave, dev);
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
w1_write_8(sl->master, HDQ_CMD_READ | reg);
val = w1_read_8(sl->master);
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return val;
}
diff --git a/drivers/w1/slaves/w1_ds2408.c b/drivers/w1/slaves/w1_ds2408.c
index 8e813eed0f0a..441ad3a3b586 100644
--- a/drivers/w1/slaves/w1_ds2408.c
+++ b/drivers/w1/slaves/w1_ds2408.c
@@ -52,11 +52,11 @@ static int _read_reg(struct w1_slave *sl, u8 address, unsigned char* buf)
if (!buf)
return -EINVAL;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
dev_dbg(&sl->dev, "mutex locked");
if (w1_reset_select_slave(sl)) {
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return -EIO;
}
@@ -66,7 +66,7 @@ static int _read_reg(struct w1_slave *sl, u8 address, unsigned char* buf)
w1_write_block(sl->master, wrbuf, 3);
*buf = w1_read_8(sl->master);
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
dev_dbg(&sl->dev, "mutex unlocked");
return 1;
}
@@ -165,7 +165,7 @@ static ssize_t w1_f29_write_output(
return -EFAULT;
dev_dbg(&sl->dev, "locking mutex for write_output");
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
dev_dbg(&sl->dev, "mutex locked");
if (w1_reset_select_slave(sl))
@@ -200,14 +200,14 @@ static ssize_t w1_f29_write_output(
/* read the result of the READ_PIO_REGS command */
if (w1_read_8(sl->master) == *buf) {
/* success! */
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
dev_dbg(&sl->dev,
"mutex unlocked, retries:%d", retries);
return 1;
}
}
error:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
dev_dbg(&sl->dev, "mutex unlocked in error, retries:%d", retries);
return -EIO;
@@ -228,7 +228,7 @@ static ssize_t w1_f29_write_activity(
if (count != 1 || off != 0)
return -EFAULT;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
if (w1_reset_select_slave(sl))
goto error;
@@ -236,7 +236,7 @@ static ssize_t w1_f29_write_activity(
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->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return 1;
}
if (w1_reset_resume_command(sl->master))
@@ -244,7 +244,7 @@ static ssize_t w1_f29_write_activity(
}
error:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return -EIO;
}
@@ -263,7 +263,7 @@ static ssize_t w1_f29_write_status_control(
if (count != 1 || off != 0)
return -EFAULT;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
if (w1_reset_select_slave(sl))
goto error;
@@ -285,12 +285,12 @@ static ssize_t w1_f29_write_status_control(
w1_write_block(sl->master, w1_buf, 3);
if (w1_read_8(sl->master) == *buf) {
/* success! */
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return 1;
}
}
error:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return -EIO;
}
diff --git a/drivers/w1/slaves/w1_ds2423.c b/drivers/w1/slaves/w1_ds2423.c
index 7a7dbe5026f1..40a10b5ed120 100644
--- a/drivers/w1/slaves/w1_ds2423.c
+++ b/drivers/w1/slaves/w1_ds2423.c
@@ -66,7 +66,7 @@ static ssize_t w1_counter_read(struct device *device,
wrbuf[0] = 0xA5;
wrbuf[1] = rom_addr & 0xFF;
wrbuf[2] = rom_addr >> 8;
- mutex_lock(&dev->mutex);
+ mutex_lock(&dev->bus_mutex);
if (!w1_reset_select_slave(sl)) {
w1_write_block(dev, wrbuf, 3);
read_byte_count = 0;
@@ -124,7 +124,7 @@ static ssize_t w1_counter_read(struct device *device,
} else {
c -= snprintf(out_buf + PAGE_SIZE - c, c, "Connection error");
}
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->bus_mutex);
return PAGE_SIZE - c;
}
diff --git a/drivers/w1/slaves/w1_ds2431.c b/drivers/w1/slaves/w1_ds2431.c
index 84e2410aec1d..984b30331a45 100644
--- a/drivers/w1/slaves/w1_ds2431.c
+++ b/drivers/w1/slaves/w1_ds2431.c
@@ -107,7 +107,7 @@ static ssize_t w1_f2d_read_bin(struct file *filp, struct kobject *kobj,
if (count == 0)
return 0;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
/* read directly from the EEPROM in chunks of W1_F2D_READ_MAXLEN */
while (todo > 0) {
@@ -126,7 +126,7 @@ static ssize_t w1_f2d_read_bin(struct file *filp, struct kobject *kobj,
off += W1_F2D_READ_MAXLEN;
}
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return count;
}
@@ -214,7 +214,7 @@ static ssize_t w1_f2d_write_bin(struct file *filp, struct kobject *kobj,
if (count == 0)
return 0;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
/* Can only write data in blocks of the size of the scratchpad */
addr = off;
@@ -259,7 +259,7 @@ static ssize_t w1_f2d_write_bin(struct file *filp, struct kobject *kobj,
}
out_up:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return count;
}
diff --git a/drivers/w1/slaves/w1_ds2433.c b/drivers/w1/slaves/w1_ds2433.c
index 0f7b8f9c509a..85f2cdb27fa2 100644
--- a/drivers/w1/slaves/w1_ds2433.c
+++ b/drivers/w1/slaves/w1_ds2433.c
@@ -107,7 +107,7 @@ static ssize_t w1_f23_read_bin(struct file *filp, struct kobject *kobj,
if ((count = w1_f23_fix_count(off, count, W1_EEPROM_SIZE)) == 0)
return 0;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
#ifdef CONFIG_W1_SLAVE_DS2433_CRC
@@ -138,7 +138,7 @@ static ssize_t w1_f23_read_bin(struct file *filp, struct kobject *kobj,
#endif /* CONFIG_W1_SLAVE_DS2433_CRC */
out_up:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return count;
}
@@ -233,7 +233,7 @@ static ssize_t w1_f23_write_bin(struct file *filp, struct kobject *kobj,
}
#endif /* CONFIG_W1_SLAVE_DS2433_CRC */
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
/* Can only write data to one page at a time */
idx = 0;
@@ -251,7 +251,7 @@ static ssize_t w1_f23_write_bin(struct file *filp, struct kobject *kobj,
}
out_up:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return count;
}
diff --git a/drivers/w1/slaves/w1_ds2760.c b/drivers/w1/slaves/w1_ds2760.c
index 5754c9a4f58b..aa7bd5fa2fa8 100644
--- a/drivers/w1/slaves/w1_ds2760.c
+++ b/drivers/w1/slaves/w1_ds2760.c
@@ -31,7 +31,7 @@ static int w1_ds2760_io(struct device *dev, char *buf, int addr, size_t count,
if (!dev)
return 0;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
if (addr > DS2760_DATA_SIZE || addr < 0) {
count = 0;
@@ -54,7 +54,7 @@ static int w1_ds2760_io(struct device *dev, char *buf, int addr, size_t count,
}
out:
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return count;
}
@@ -76,14 +76,14 @@ static int w1_ds2760_eeprom_cmd(struct device *dev, int addr, int cmd)
if (!dev)
return -EINVAL;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
if (w1_reset_select_slave(sl) == 0) {
w1_write_8(sl->master, cmd);
w1_write_8(sl->master, addr);
}
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return 0;
}
diff --git a/drivers/w1/slaves/w1_ds2780.c b/drivers/w1/slaves/w1_ds2780.c
index 39f78c0b143c..7b09307de0ef 100644
--- a/drivers/w1/slaves/w1_ds2780.c
+++ b/drivers/w1/slaves/w1_ds2780.c
@@ -60,30 +60,16 @@ int w1_ds2780_io(struct device *dev, char *buf, int addr, size_t count,
if (!dev)
return -ENODEV;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
ret = w1_ds2780_do_io(dev, buf, addr, count, io);
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return ret;
}
EXPORT_SYMBOL(w1_ds2780_io);
-int w1_ds2780_io_nolock(struct device *dev, char *buf, int addr, size_t count,
- int io)
-{
- int ret;
-
- if (!dev)
- return -ENODEV;
-
- ret = w1_ds2780_do_io(dev, buf, addr, count, io);
-
- return ret;
-}
-EXPORT_SYMBOL(w1_ds2780_io_nolock);
-
int w1_ds2780_eeprom_cmd(struct device *dev, int addr, int cmd)
{
struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
@@ -91,14 +77,14 @@ int w1_ds2780_eeprom_cmd(struct device *dev, int addr, int cmd)
if (!dev)
return -EINVAL;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
if (w1_reset_select_slave(sl) == 0) {
w1_write_8(sl->master, cmd);
w1_write_8(sl->master, addr);
}
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return 0;
}
EXPORT_SYMBOL(w1_ds2780_eeprom_cmd);
diff --git a/drivers/w1/slaves/w1_ds2780.h b/drivers/w1/slaves/w1_ds2780.h
index 737379365021..a1fba79eb1b5 100644
--- a/drivers/w1/slaves/w1_ds2780.h
+++ b/drivers/w1/slaves/w1_ds2780.h
@@ -124,8 +124,6 @@
extern int w1_ds2780_io(struct device *dev, char *buf, int addr, size_t count,
int io);
-extern int w1_ds2780_io_nolock(struct device *dev, char *buf, int addr,
- size_t count, int io);
extern int w1_ds2780_eeprom_cmd(struct device *dev, int addr, int cmd);
#endif /* !_W1_DS2780_H */
diff --git a/drivers/w1/slaves/w1_ds2781.c b/drivers/w1/slaves/w1_ds2781.c
index 0d0c7985293f..877daf74159c 100644
--- a/drivers/w1/slaves/w1_ds2781.c
+++ b/drivers/w1/slaves/w1_ds2781.c
@@ -58,30 +58,16 @@ int w1_ds2781_io(struct device *dev, char *buf, int addr, size_t count,
if (!dev)
return -ENODEV;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
ret = w1_ds2781_do_io(dev, buf, addr, count, io);
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return ret;
}
EXPORT_SYMBOL(w1_ds2781_io);
-int w1_ds2781_io_nolock(struct device *dev, char *buf, int addr, size_t count,
- int io)
-{
- int ret;
-
- if (!dev)
- return -ENODEV;
-
- ret = w1_ds2781_do_io(dev, buf, addr, count, io);
-
- return ret;
-}
-EXPORT_SYMBOL(w1_ds2781_io_nolock);
-
int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd)
{
struct w1_slave *sl = container_of(dev, struct w1_slave, dev);
@@ -89,14 +75,14 @@ int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd)
if (!dev)
return -EINVAL;
- mutex_lock(&sl->master->mutex);
+ mutex_lock(&sl->master->bus_mutex);
if (w1_reset_select_slave(sl) == 0) {
w1_write_8(sl->master, cmd);
w1_write_8(sl->master, addr);
}
- mutex_unlock(&sl->master->mutex);
+ mutex_unlock(&sl->master->bus_mutex);
return 0;
}
EXPORT_SYMBOL(w1_ds2781_eeprom_cmd);
diff --git a/drivers/w1/slaves/w1_ds2781.h b/drivers/w1/slaves/w1_ds2781.h
index 82bc66497b43..557dfb0b4f64 100644
--- a/drivers/w1/slaves/w1_ds2781.h
+++ b/drivers/w1/slaves/w1_ds2781.h
@@ -129,8 +129,6 @@
extern int w1_ds2781_io(struct device *dev, char *buf, int addr, size_t count,
int io);
-extern int w1_ds2781_io_nolock(struct device *dev, char *buf, int addr,
- size_t count, int io);
extern int w1_ds2781_eeprom_cmd(struct device *dev, int addr, int cmd);
#endif /* !_W1_DS2781_H */
diff --git a/drivers/w1/slaves/w1_ds28e04.c b/drivers/w1/slaves/w1_ds28e04.c
new file mode 100644
index 000000000000..98117db595bb
--- /dev/null
+++ b/drivers/w1/slaves/w1_ds28e04.c
@@ -0,0 +1,469 @@
+/*
+ * w1_ds28e04.c - w1 family 1C (DS28E04) driver
+ *
+ * Copyright (c) 2012 Markus Franke <franke.m@sebakmt.com>
+ *
+ * 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 <linux/crc16.h>
+#include <linux/uaccess.h>
+
+#define CRC16_INIT 0
+#define CRC16_VALID 0xb001
+
+#include "../w1.h"
+#include "../w1_int.h"
+#include "../w1_family.h"
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Markus Franke <franke.m@sebakmt.com>, <franm@hrz.tu-chemnitz.de>");
+MODULE_DESCRIPTION("w1 family 1C driver for DS28E04, 4kb EEPROM and PIO");
+
+/* Allow the strong pullup to be disabled, but default to enabled.
+ * If it was disabled a parasite powered device might not get the required
+ * current to copy the data from the scratchpad to EEPROM. If it is enabled
+ * parasite powered devices have a better chance of getting the current
+ * required.
+ */
+static int w1_strong_pullup = 1;
+module_param_named(strong_pullup, w1_strong_pullup, int, 0);
+
+/* enable/disable CRC checking on DS28E04-100 memory accesses */
+static char w1_enable_crccheck = 1;
+
+#define W1_EEPROM_SIZE 512
+#define W1_PAGE_COUNT 16
+#define W1_PAGE_SIZE 32
+#define W1_PAGE_BITS 5
+#define W1_PAGE_MASK 0x1F
+
+#define W1_F1C_READ_EEPROM 0xF0
+#define W1_F1C_WRITE_SCRATCH 0x0F
+#define W1_F1C_READ_SCRATCH 0xAA
+#define W1_F1C_COPY_SCRATCH 0x55
+#define W1_F1C_ACCESS_WRITE 0x5A
+
+#define W1_1C_REG_LOGIC_STATE 0x220
+
+struct w1_f1C_data {
+ u8 memory[W1_EEPROM_SIZE];
+ u32 validcrc;
+};
+
+/**
+ * Check the file size bounds and adjusts count as needed.
+ * This would not be needed if the file size didn't reset to 0 after a write.
+ */
+static inline size_t w1_f1C_fix_count(loff_t off, size_t count, size_t size)
+{
+ if (off > size)
+ return 0;
+
+ if ((off + count) > size)
+ return size - off;
+
+ return count;
+}
+
+static int w1_f1C_refresh_block(struct w1_slave *sl, struct w1_f1C_data *data,
+ int block)
+{
+ u8 wrbuf[3];
+ int off = block * W1_PAGE_SIZE;
+
+ if (data->validcrc & (1 << block))
+ return 0;
+
+ if (w1_reset_select_slave(sl)) {
+ data->validcrc = 0;
+ return -EIO;
+ }
+
+ wrbuf[0] = W1_F1C_READ_EEPROM;
+ wrbuf[1] = off & 0xff;
+ wrbuf[2] = off >> 8;
+ w1_write_block(sl->master, wrbuf, 3);
+ w1_read_block(sl->master, &data->memory[off], W1_PAGE_SIZE);
+
+ /* cache the block if the CRC is valid */
+ if (crc16(CRC16_INIT, &data->memory[off], W1_PAGE_SIZE) == CRC16_VALID)
+ data->validcrc |= (1 << block);
+
+ return 0;
+}
+
+static int w1_f1C_read(struct w1_slave *sl, int addr, int len, char *data)
+{
+ u8 wrbuf[3];
+
+ /* read directly from the EEPROM */
+ if (w1_reset_select_slave(sl))
+ return -EIO;
+
+ wrbuf[0] = W1_F1C_READ_EEPROM;
+ wrbuf[1] = addr & 0xff;
+ wrbuf[2] = addr >> 8;
+
+ w1_write_block(sl->master, wrbuf, sizeof(wrbuf));
+ return w1_read_block(sl->master, data, len);
+}
+
+static ssize_t w1_f1C_read_bin(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);
+ struct w1_f1C_data *data = sl->family_data;
+ int i, min_page, max_page;
+
+ count = w1_f1C_fix_count(off, count, W1_EEPROM_SIZE);
+ if (count == 0)
+ return 0;
+
+ mutex_lock(&sl->master->mutex);
+
+ if (w1_enable_crccheck) {
+ min_page = (off >> W1_PAGE_BITS);
+ max_page = (off + count - 1) >> W1_PAGE_BITS;
+ for (i = min_page; i <= max_page; i++) {
+ if (w1_f1C_refresh_block(sl, data, i)) {
+ count = -EIO;
+ goto out_up;
+ }
+ }
+ memcpy(buf, &data->memory[off], count);
+ } else {
+ count = w1_f1C_read(sl, off, count, buf);
+ }
+
+out_up:
+ mutex_unlock(&sl->master->mutex);
+
+ return count;
+}
+
+/**
+ * Writes to the scratchpad and reads it back for verification.
+ * Then copies the scratchpad to EEPROM.
+ * The data must be on one page.
+ * The master must be locked.
+ *
+ * @param sl The slave structure
+ * @param addr Address for the write
+ * @param len length must be <= (W1_PAGE_SIZE - (addr & W1_PAGE_MASK))
+ * @param data The data to write
+ * @return 0=Success -1=failure
+ */
+static int w1_f1C_write(struct w1_slave *sl, int addr, int len, const u8 *data)
+{
+ u8 wrbuf[4];
+ u8 rdbuf[W1_PAGE_SIZE + 3];
+ u8 es = (addr + len - 1) & 0x1f;
+ unsigned int tm = 10;
+ int i;
+ struct w1_f1C_data *f1C = sl->family_data;
+
+ /* Write the data to the scratchpad */
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ wrbuf[0] = W1_F1C_WRITE_SCRATCH;
+ wrbuf[1] = addr & 0xff;
+ wrbuf[2] = addr >> 8;
+
+ w1_write_block(sl->master, wrbuf, 3);
+ w1_write_block(sl->master, data, len);
+
+ /* Read the scratchpad and verify */
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ w1_write_8(sl->master, W1_F1C_READ_SCRATCH);
+ w1_read_block(sl->master, rdbuf, len + 3);
+
+ /* Compare what was read against the data written */
+ if ((rdbuf[0] != wrbuf[1]) || (rdbuf[1] != wrbuf[2]) ||
+ (rdbuf[2] != es) || (memcmp(data, &rdbuf[3], len) != 0))
+ return -1;
+
+ /* Copy the scratchpad to EEPROM */
+ if (w1_reset_select_slave(sl))
+ return -1;
+
+ wrbuf[0] = W1_F1C_COPY_SCRATCH;
+ wrbuf[3] = es;
+
+ for (i = 0; i < sizeof(wrbuf); ++i) {
+ /* issue 10ms strong pullup (or delay) on the last byte
+ for writing the data from the scratchpad to EEPROM */
+ if (w1_strong_pullup && i == sizeof(wrbuf)-1)
+ w1_next_pullup(sl->master, tm);
+
+ w1_write_8(sl->master, wrbuf[i]);
+ }
+
+ if (!w1_strong_pullup)
+ msleep(tm);
+
+ if (w1_enable_crccheck) {
+ /* invalidate cached data */
+ f1C->validcrc &= ~(1 << (addr >> W1_PAGE_BITS));
+ }
+
+ /* Reset the bus to wake up the EEPROM (this may not be needed) */
+ w1_reset_bus(sl->master);
+
+ return 0;
+}
+
+static ssize_t w1_f1C_write_bin(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);
+ int addr, len, idx;
+
+ count = w1_f1C_fix_count(off, count, W1_EEPROM_SIZE);
+ if (count == 0)
+ return 0;
+
+ if (w1_enable_crccheck) {
+ /* can only write full blocks in cached mode */
+ if ((off & W1_PAGE_MASK) || (count & W1_PAGE_MASK)) {
+ dev_err(&sl->dev, "invalid offset/count off=%d cnt=%zd\n",
+ (int)off, count);
+ return -EINVAL;
+ }
+
+ /* make sure the block CRCs are valid */
+ for (idx = 0; idx < count; idx += W1_PAGE_SIZE) {
+ if (crc16(CRC16_INIT, &buf[idx], W1_PAGE_SIZE)
+ != CRC16_VALID) {
+ dev_err(&sl->dev, "bad CRC at offset %d\n",
+ (int)off);
+ return -EINVAL;
+ }
+ }
+ }
+
+ mutex_lock(&sl->master->mutex);
+
+ /* Can only write data to one page at a time */
+ idx = 0;
+ while (idx < count) {
+ addr = off + idx;
+ len = W1_PAGE_SIZE - (addr & W1_PAGE_MASK);
+ if (len > (count - idx))
+ len = count - idx;
+
+ if (w1_f1C_write(sl, addr, len, &buf[idx]) < 0) {
+ count = -EIO;
+ goto out_up;
+ }
+ idx += len;
+ }
+
+out_up:
+ mutex_unlock(&sl->master->mutex);
+
+ return count;
+}
+
+static ssize_t w1_f1C_read_pio(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);
+ int ret;
+
+ /* check arguments */
+ if (off != 0 || count != 1 || buf == NULL)
+ return -EINVAL;
+
+ mutex_lock(&sl->master->mutex);
+ ret = w1_f1C_read(sl, W1_1C_REG_LOGIC_STATE, count, buf);
+ mutex_unlock(&sl->master->mutex);
+
+ return ret;
+}
+
+static ssize_t w1_f1C_write_pio(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 wrbuf[3];
+ u8 ack;
+
+ /* check arguments */
+ if (off != 0 || count != 1 || buf == NULL)
+ return -EINVAL;
+
+ mutex_lock(&sl->master->mutex);
+
+ /* Write the PIO data */
+ if (w1_reset_select_slave(sl)) {
+ mutex_unlock(&sl->master->mutex);
+ return -1;
+ }
+
+ /* set bit 7..2 to value '1' */
+ *buf = *buf | 0xFC;
+
+ wrbuf[0] = W1_F1C_ACCESS_WRITE;
+ wrbuf[1] = *buf;
+ wrbuf[2] = ~(*buf);
+ w1_write_block(sl->master, wrbuf, 3);
+
+ w1_read_block(sl->master, &ack, sizeof(ack));
+
+ mutex_unlock(&sl->master->mutex);
+
+ /* check for acknowledgement */
+ if (ack != 0xAA)
+ return -EIO;
+
+ return count;
+}
+
+static ssize_t w1_f1C_show_crccheck(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ if (put_user(w1_enable_crccheck + 0x30, buf))
+ return -EFAULT;
+
+ return sizeof(w1_enable_crccheck);
+}
+
+static ssize_t w1_f1C_store_crccheck(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ char val;
+
+ if (count != 1 || !buf)
+ return -EINVAL;
+
+ if (get_user(val, buf))
+ return -EFAULT;
+
+ /* convert to decimal */
+ val = val - 0x30;
+ if (val != 0 && val != 1)
+ return -EINVAL;
+
+ /* set the new value */
+ w1_enable_crccheck = val;
+
+ return sizeof(w1_enable_crccheck);
+}
+
+#define NB_SYSFS_BIN_FILES 2
+static struct bin_attribute w1_f1C_bin_attr[NB_SYSFS_BIN_FILES] = {
+ {
+ .attr = {
+ .name = "eeprom",
+ .mode = S_IRUGO | S_IWUSR,
+ },
+ .size = W1_EEPROM_SIZE,
+ .read = w1_f1C_read_bin,
+ .write = w1_f1C_write_bin,
+ },
+ {
+ .attr = {
+ .name = "pio",
+ .mode = S_IRUGO | S_IWUSR,
+ },
+ .size = 1,
+ .read = w1_f1C_read_pio,
+ .write = w1_f1C_write_pio,
+ }
+};
+
+static DEVICE_ATTR(crccheck, S_IWUSR | S_IRUGO,
+ w1_f1C_show_crccheck, w1_f1C_store_crccheck);
+
+static int w1_f1C_add_slave(struct w1_slave *sl)
+{
+ int err = 0;
+ int i;
+ struct w1_f1C_data *data = NULL;
+
+ if (w1_enable_crccheck) {
+ data = kzalloc(sizeof(struct w1_f1C_data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+ sl->family_data = data;
+ }
+
+ /* create binary sysfs attributes */
+ for (i = 0; i < NB_SYSFS_BIN_FILES && !err; ++i)
+ err = sysfs_create_bin_file(
+ &sl->dev.kobj, &(w1_f1C_bin_attr[i]));
+
+ if (!err) {
+ /* create device attributes */
+ err = device_create_file(&sl->dev, &dev_attr_crccheck);
+ }
+
+ if (err) {
+ /* remove binary sysfs attributes */
+ for (i = 0; i < NB_SYSFS_BIN_FILES; ++i)
+ sysfs_remove_bin_file(
+ &sl->dev.kobj, &(w1_f1C_bin_attr[i]));
+
+ kfree(data);
+ }
+
+ return err;
+}
+
+static void w1_f1C_remove_slave(struct w1_slave *sl)
+{
+ int i;
+
+ kfree(sl->family_data);
+ sl->family_data = NULL;
+
+ /* remove device attributes */
+ device_remove_file(&sl->dev, &dev_attr_crccheck);
+
+ /* remove binary sysfs attributes */
+ for (i = 0; i < NB_SYSFS_BIN_FILES; ++i)
+ sysfs_remove_bin_file(&sl->dev.kobj, &(w1_f1C_bin_attr[i]));
+}
+
+static struct w1_family_ops w1_f1C_fops = {
+ .add_slave = w1_f1C_add_slave,
+ .remove_slave = w1_f1C_remove_slave,
+};
+
+static struct w1_family w1_family_1C = {
+ .fid = W1_FAMILY_DS28E04,
+ .fops = &w1_f1C_fops,
+};
+
+static int __init w1_f1C_init(void)
+{
+ return w1_register_family(&w1_family_1C);
+}
+
+static void __exit w1_f1C_fini(void)
+{
+ w1_unregister_family(&w1_family_1C);
+}
+
+module_init(w1_f1C_init);
+module_exit(w1_f1C_fini);
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
index ff29ae747ee8..d90062b211f8 100644
--- a/drivers/w1/slaves/w1_therm.c
+++ b/drivers/w1/slaves/w1_therm.c
@@ -179,7 +179,7 @@ static ssize_t w1_therm_read(struct device *device,
int i, max_trying = 10;
ssize_t c = PAGE_SIZE;
- i = mutex_lock_interruptible(&dev->mutex);
+ i = mutex_lock_interruptible(&dev->bus_mutex);
if (i != 0)
return i;
@@ -207,19 +207,19 @@ static ssize_t w1_therm_read(struct device *device,
w1_write_8(dev, W1_CONVERT_TEMP);
if (external_power) {
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->bus_mutex);
sleep_rem = msleep_interruptible(tm);
if (sleep_rem != 0)
return -EINTR;
- i = mutex_lock_interruptible(&dev->mutex);
+ i = mutex_lock_interruptible(&dev->bus_mutex);
if (i != 0)
return i;
} else if (!w1_strong_pullup) {
sleep_rem = msleep_interruptible(tm);
if (sleep_rem != 0) {
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->bus_mutex);
return -EINTR;
}
}
@@ -258,7 +258,7 @@ static ssize_t w1_therm_read(struct device *device,
c -= snprintf(buf + PAGE_SIZE - c, c, "t=%d\n",
w1_convert_temp(rom, sl->family->fid));
- mutex_unlock(&dev->mutex);
+ mutex_unlock(&dev->bus_mutex);
return PAGE_SIZE - c;
}
diff --git a/drivers/w1/w1.c b/drivers/w1/w1.c
index 2f2e894ea0c8..1a574370d2cd 100644
--- a/drivers/w1/w1.c
+++ b/drivers/w1/w1.c
@@ -557,7 +557,7 @@ static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
struct w1_master *md = NULL;
struct w1_slave *sl = NULL;
char *event_owner, *name;
- int err;
+ int err = 0;
if (dev->driver == &w1_master_driver) {
md = container_of(dev, struct w1_master, dev);
@@ -576,19 +576,17 @@ static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
event_owner, name, dev_name(dev));
if (dev->driver != &w1_slave_driver || !sl)
- return 0;
+ goto end;
err = add_uevent_var(env, "W1_FID=%02X", sl->reg_num.family);
if (err)
- return err;
+ goto end;
err = add_uevent_var(env, "W1_SLAVE_ID=%024LX",
(unsigned long long)sl->reg_num.id);
- if (err)
- return err;
-
- return 0;
-};
+end:
+ return err;
+}
#else
static int w1_uevent(struct device *dev, struct kobj_uevent_env *env)
{
@@ -887,16 +885,21 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb
*
* Return 0 - device(s) present, 1 - no devices present.
*/
+ mutex_lock(&dev->bus_mutex);
if (w1_reset_bus(dev)) {
+ mutex_unlock(&dev->bus_mutex);
dev_dbg(&dev->dev, "No devices present on the wire.\n");
break;
}
/* Do fast search on single slave bus */
if (dev->max_slave_count == 1) {
+ int rv;
w1_write_8(dev, W1_READ_ROM);
+ rv = w1_read_block(dev, (u8 *)&rn, 8);
+ mutex_unlock(&dev->bus_mutex);
- if (w1_read_block(dev, (u8 *)&rn, 8) == 8 && rn)
+ if (rv == 8 && rn)
cb(dev, rn);
break;
@@ -929,10 +932,12 @@ void w1_search(struct w1_master *dev, u8 search_type, w1_slave_found_callback cb
rn |= (tmp64 << i);
if (kthread_should_stop()) {
+ mutex_unlock(&dev->bus_mutex);
dev_dbg(&dev->dev, "Abort w1_search\n");
return;
}
}
+ mutex_unlock(&dev->bus_mutex);
if ( (triplet_ret & 0x03) != 0x03 ) {
if ( (desc_bit == last_zero) || (last_zero < 0))
diff --git a/drivers/w1/w1.h b/drivers/w1/w1.h
index 4d012ca3f32c..45908e56c2f8 100644
--- a/drivers/w1/w1.h
+++ b/drivers/w1/w1.h
@@ -180,6 +180,7 @@ struct w1_master
struct task_struct *thread;
struct mutex mutex;
+ struct mutex bus_mutex;
struct device_driver *driver;
struct device dev;
diff --git a/drivers/w1/w1_family.h b/drivers/w1/w1_family.h
index 874aeb05011b..b00ada44a89b 100644
--- a/drivers/w1/w1_family.h
+++ b/drivers/w1/w1_family.h
@@ -30,6 +30,7 @@
#define W1_FAMILY_SMEM_01 0x01
#define W1_FAMILY_SMEM_81 0x81
#define W1_THERM_DS18S20 0x10
+#define W1_FAMILY_DS28E04 0x1C
#define W1_COUNTER_DS2423 0x1D
#define W1_THERM_DS1822 0x22
#define W1_EEPROM_DS2433 0x23
diff --git a/drivers/w1/w1_int.c b/drivers/w1/w1_int.c
index 68288355727a..5a98649f6abc 100644
--- a/drivers/w1/w1_int.c
+++ b/drivers/w1/w1_int.c
@@ -76,6 +76,7 @@ static struct w1_master * w1_alloc_dev(u32 id, int slave_count, int slave_ttl,
INIT_LIST_HEAD(&dev->slist);
mutex_init(&dev->mutex);
+ mutex_init(&dev->bus_mutex);
memcpy(&dev->dev, device, sizeof(struct device));
dev_set_name(&dev->dev, "w1_bus_master%u", dev->id);
@@ -117,7 +118,7 @@ int w1_add_master_device(struct w1_bus_master *master)
return(-EINVAL);
}
/* While it would be electrically possible to make a device that
- * generated a strong pullup in bit bang mode, only hardare that
+ * generated a strong pullup in bit bang mode, only hardware that
* controls 1-wire time frames are even expected to support a strong
* pullup. w1_io.c would need to support calling set_pullup before
* the last write_bit operation of a w1_write_8 which it currently