diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/w1/slaves/w1_ds2413.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/drivers/w1/slaves/w1_ds2413.c b/drivers/w1/slaves/w1_ds2413.c index d63778c70568..21f08ac8a4e0 100644 --- a/drivers/w1/slaves/w1_ds2413.c +++ b/drivers/w1/slaves/w1_ds2413.c @@ -24,6 +24,7 @@ #define W1_F3A_FUNC_PIO_ACCESS_READ 0xF5 #define W1_F3A_FUNC_PIO_ACCESS_WRITE 0x5A #define W1_F3A_SUCCESS_CONFIRM_BYTE 0xAA +#define W1_F3A_INVALID_PIO_STATE 0xFF static ssize_t state_read(struct file *filp, struct kobject *kobj, struct bin_attribute *bin_attr, char *buf, loff_t off, @@ -45,6 +46,7 @@ static ssize_t state_read(struct file *filp, struct kobject *kobj, mutex_lock(&sl->master->bus_mutex); dev_dbg(&sl->dev, "mutex locked"); +next: if (w1_reset_select_slave(sl)) goto out; @@ -52,10 +54,15 @@ static ssize_t state_read(struct file *filp, struct kobject *kobj, w1_write_8(sl->master, W1_F3A_FUNC_PIO_ACCESS_READ); *buf = w1_read_8(sl->master); - /* check for correct complement */ if ((*buf & 0x0F) == ((~*buf >> 4) & 0x0F)) { + /* complement is correct */ bytes_read = 1; goto out; + } else if (*buf == W1_F3A_INVALID_PIO_STATE) { + /* slave didn't respond, try to select it again */ + dev_warn(&sl->dev, "slave device did not respond to PIO_ACCESS_READ, " \ + "reselecting, retries left: %d\n", retries); + goto next; } if (w1_reset_resume_command(sl->master)) |