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-rw-r--r--drivers/w1/masters/ds2482.c18
-rw-r--r--drivers/w1/slaves/w1_ds2408.c76
-rw-r--r--drivers/w1/w1_io.c3
3 files changed, 51 insertions, 46 deletions
diff --git a/drivers/w1/masters/ds2482.c b/drivers/w1/masters/ds2482.c
index 8b5e598ffdb3..8f2b25f1614c 100644
--- a/drivers/w1/masters/ds2482.c
+++ b/drivers/w1/masters/ds2482.c
@@ -37,6 +37,11 @@ module_param_named(active_pullup, ds2482_active_pullup, int, 0644);
MODULE_PARM_DESC(active_pullup, "Active pullup (apply to all buses): " \
"0-disable, 1-enable (default)");
+/* extra configurations - e.g. 1WS */
+static int extra_config;
+module_param(extra_config, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(extra_config, "Extra Configuration settings 1=APU,2=PPM,3=SPU,8=1WS");
+
/**
* The DS2482 registers - there are 3 registers that are addressed by a read
* pointer. The read pointer is set by the last command executed.
@@ -70,8 +75,6 @@ MODULE_PARM_DESC(active_pullup, "Active pullup (apply to all buses): " \
#define DS2482_REG_CFG_PPM 0x02 /* presence pulse masking */
#define DS2482_REG_CFG_APU 0x01 /* active pull-up */
-/* extra configurations - e.g. 1WS */
-static int extra_config;
/**
* Write and verify codes for the CHANNEL_SELECT command (DS2482-800 only).
@@ -130,6 +133,8 @@ struct ds2482_data {
*/
static inline u8 ds2482_calculate_config(u8 conf)
{
+ conf |= extra_config;
+
if (ds2482_active_pullup)
conf |= DS2482_REG_CFG_APU;
@@ -405,7 +410,7 @@ static u8 ds2482_w1_reset_bus(void *data)
/* If the chip did reset since detect, re-config it */
if (err & DS2482_REG_STS_RST)
ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,
- ds2482_calculate_config(extra_config));
+ ds2482_calculate_config(0x00));
}
mutex_unlock(&pdev->access_lock);
@@ -431,7 +436,8 @@ static u8 ds2482_w1_set_pullup(void *data, int delay)
ds2482_wait_1wire_idle(pdev);
/* note: it seems like both SPU and APU have to be set! */
retval = ds2482_send_cmd_data(pdev, DS2482_CMD_WRITE_CONFIG,
- ds2482_calculate_config(extra_config|DS2482_REG_CFG_SPU|DS2482_REG_CFG_APU));
+ ds2482_calculate_config(DS2482_REG_CFG_SPU |
+ DS2482_REG_CFG_APU));
ds2482_wait_1wire_idle(pdev);
}
@@ -484,7 +490,7 @@ static int ds2482_probe(struct i2c_client *client,
/* Set all config items to 0 (off) */
ds2482_send_cmd_data(data, DS2482_CMD_WRITE_CONFIG,
- ds2482_calculate_config(extra_config));
+ ds2482_calculate_config(0x00));
mutex_init(&data->access_lock);
@@ -559,7 +565,5 @@ module_i2c_driver(ds2482_driver);
MODULE_AUTHOR("Ben Gardner <bgardner@wabtec.com>");
MODULE_DESCRIPTION("DS2482 driver");
-module_param(extra_config, int, S_IRUGO | S_IWUSR);
-MODULE_PARM_DESC(extra_config, "Extra Configuration settings 1=APU,2=PPM,3=SPU,8=1WS");
MODULE_LICENSE("GPL");
diff --git a/drivers/w1/slaves/w1_ds2408.c b/drivers/w1/slaves/w1_ds2408.c
index b535d5ec35b6..92e8f0755b9a 100644
--- a/drivers/w1/slaves/w1_ds2408.c
+++ b/drivers/w1/slaves/w1_ds2408.c
@@ -138,14 +138,37 @@ static ssize_t status_control_read(struct file *filp, struct kobject *kobj,
W1_F29_REG_CONTROL_AND_STATUS, buf);
}
+#ifdef fCONFIG_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];
- u8 readBack;
unsigned int retries = W1_F29_RETRIES;
+ ssize_t bytes_written = -EIO;
if (count != 1 || off != 0)
return -EFAULT;
@@ -155,54 +178,33 @@ static ssize_t output_write(struct file *filp, struct kobject *kobj,
dev_dbg(&sl->dev, "mutex locked");
if (w1_reset_select_slave(sl))
- goto error;
+ goto out;
- while (retries--) {
+ 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);
- readBack = w1_read_8(sl->master);
+ w1_write_block(sl->master, w1_buf, 3);
- if (readBack != W1_F29_SUCCESS_CONFIRM_BYTE) {
- if (w1_reset_resume_command(sl->master))
- goto error;
- /* try again, the slave is ready for a command */
- continue;
+ if (w1_read_8(sl->master) == W1_F29_SUCCESS_CONFIRM_BYTE &&
+ optional_read_back_valid(sl, *buf)) {
+ bytes_written = 1;
+ goto out;
}
-#ifdef CONFIG_W1_SLAVE_DS2408_READBACK
- /* here the master could read another byte which
- would be the PIO reg (the actual pin logic state)
- since in this driver we don't know which pins are
- in and outs, there's no value to read the state and
- compare. with (*buf) so end this command abruptly: */
if (w1_reset_resume_command(sl->master))
- goto error;
+ goto out; /* unrecoverable error */
+ /* try again, the slave is ready for a command */
+ } while (--retries);
- /* go read back the output latches */
- /* (the direct effect of the write above) */
- 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);
- /* read the result of the READ_PIO_REGS command */
- if (w1_read_8(sl->master) == *buf)
-#endif
- {
- /* success! */
- mutex_unlock(&sl->master->bus_mutex);
- dev_dbg(&sl->dev,
- "mutex unlocked, retries:%d", retries);
- return 1;
- }
- }
-error:
+out:
mutex_unlock(&sl->master->bus_mutex);
- dev_dbg(&sl->dev, "mutex unlocked in error, retries:%d", retries);
- return -EIO;
+ dev_dbg(&sl->dev, "%s, mutex unlocked retries:%d\n",
+ (bytes_written > 0) ? "succeeded" : "error", retries);
+
+ return bytes_written;
}
diff --git a/drivers/w1/w1_io.c b/drivers/w1/w1_io.c
index 0364d3329c52..3516ce6718d9 100644
--- a/drivers/w1/w1_io.c
+++ b/drivers/w1/w1_io.c
@@ -432,8 +432,7 @@ int w1_reset_resume_command(struct w1_master *dev)
if (w1_reset_bus(dev))
return -1;
- /* This will make only the last matched slave perform a skip ROM. */
- w1_write_8(dev, W1_RESUME_CMD);
+ w1_write_8(dev, dev->slave_count > 1 ? W1_RESUME_CMD : W1_SKIP_ROM);
return 0;
}
EXPORT_SYMBOL_GPL(w1_reset_resume_command);