From 46a243f72de931aad2632a0f3de3612534212ae9 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Sun, 15 Jan 2012 00:16:51 +0100 Subject: [PATCH] [SCSI] st: implement PM MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This implements basic power management for SCSI tapes. Signed-off-by: Oliver Neukum Acked-by: Kai Mäkisara Signed-off-by: James Bottomley --- drivers/scsi/st.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c index 9b28f39bac26..9262cdfa4b23 100644 --- a/drivers/scsi/st.c +++ b/drivers/scsi/st.c @@ -1177,6 +1177,7 @@ static int check_tape(struct scsi_tape *STp, struct file *filp) static int st_open(struct inode *inode, struct file *filp) { int i, retval = (-EIO); + int resumed = 0; struct scsi_tape *STp; struct st_partstat *STps; int dev = TAPE_NR(inode); @@ -1211,6 +1212,11 @@ static int st_open(struct inode *inode, struct file *filp) write_unlock(&st_dev_arr_lock); STp->rew_at_close = STp->autorew_dev = (iminor(inode) & 0x80) == 0; + if (scsi_autopm_get_device(STp->device) < 0) { + retval = -EIO; + goto err_out; + } + resumed = 1; if (!scsi_block_when_processing_errors(STp->device)) { retval = (-ENXIO); goto err_out; @@ -1258,6 +1264,8 @@ static int st_open(struct inode *inode, struct file *filp) normalize_buffer(STp->buffer); STp->in_use = 0; scsi_tape_put(STp); + if (resumed) + scsi_autopm_put_device(STp->device); mutex_unlock(&st_mutex); return retval; @@ -1391,6 +1399,7 @@ static int st_release(struct inode *inode, struct file *filp) write_lock(&st_dev_arr_lock); STp->in_use = 0; write_unlock(&st_dev_arr_lock); + scsi_autopm_put_device(STp->device); scsi_tape_put(STp); return result; @@ -4154,6 +4163,7 @@ static int st_probe(struct device *dev) if (error) goto out_free_tape; } + scsi_autopm_put_device(SDp); sdev_printk(KERN_NOTICE, SDp, "Attached scsi tape %s\n", tape_name(tpnt)); @@ -4201,6 +4211,7 @@ static int st_remove(struct device *dev) struct scsi_tape *tpnt; int i, j, mode; + scsi_autopm_get_device(SDp); write_lock(&st_dev_arr_lock); for (i = 0; i < st_dev_max; i++) { tpnt = scsi_tapes[i];