w1: ds2413: output_write() cosmetic fixes / simplify

Make the output_write simpler.
Based on Jean-Francois Dagenais code from:
49695ac46861 ("w1: ds2408: reset on output_write retry with readback")

Signed-off-by: Mariusz Bialonczyk <manio@skyboo.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/w1/slaves/w1_ds2413.c b/drivers/w1/slaves/w1_ds2413.c
index 492e3d010321d18ed2a34dba66a17a82842df8bc..cd3763df69ac57c343bea91f0a91c2e67685719c 100644 (file)
--- a/drivers/w1/slaves/w1_ds2413.c
+++ b/drivers/w1/slaves/w1_ds2413.c
@@ -69,6 +69,7 @@ static ssize_t output_write(struct file *filp, struct kobject *kobj,
        struct w1_slave *sl = kobj_to_w1_slave(kobj);
        u8 w1_buf[3];
        unsigned int retries = W1_F3A_RETRIES;
+       ssize_t bytes_written = -EIO;
 
        if (count != 1 || off != 0)
                return -EFAULT;
@@ -78,7 +79,7 @@ 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;
 
        /* according to the DS2413 datasheet the most significant 6 bits
           should be set to "1"s, so do it now */
@@ -91,18 +92,20 @@ static ssize_t output_write(struct file *filp, struct kobject *kobj,
                w1_write_block(sl->master, w1_buf, 3);
 
                if (w1_read_8(sl->master) == W1_F3A_SUCCESS_CONFIRM_BYTE) {
-                       mutex_unlock(&sl->master->bus_mutex);
-                       dev_dbg(&sl->dev, "mutex unlocked, retries:%d", retries);
-                       return 1;
+                       bytes_written = 1;
+                       goto out;
                }
                if (w1_reset_resume_command(sl->master))
-                       goto error;
+                       goto out; /* unrecoverable error */
+
+               dev_warn(&sl->dev, "PIO_ACCESS_WRITE error, retries left: %d\n", retries);
        }
 
-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;
 }
 
 static BIN_ATTR(output, S_IRUGO | S_IWUSR | S_IWGRP, NULL, output_write, 1);