From 3280ce5f5483a351f49e84b48ad98df87989346a Mon Sep 17 00:00:00 2001 From: Mariusz Bialonczyk Date: Mon, 20 May 2019 09:05:55 +0200 Subject: [PATCH] w1: ds2413: output_write() cosmetic fixes / simplify commit ae2ee27aa985232f66421d7cd1c7f4b87c7dba7d upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/w1/slaves/w1_ds2413.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) --- 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 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 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 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);