libata: make ->scr_read/write callbacks return error code

Convert ->scr_read/write callbacks to return error code to better
indicate failure.  This will help handling of SCR_NOTIFICATION.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/include/linux/libata.h b/include/linux/libata.h
index cb181713d9b..c732b3e78e2 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -620,9 +620,8 @@ struct ata_port_operations {
         u8 (*irq_on) (struct ata_port *);
         u8 (*irq_ack) (struct ata_port *ap, unsigned int chk_drq);
 
-        u32 (*scr_read) (struct ata_port *ap, unsigned int sc_reg);
-        void (*scr_write) (struct ata_port *ap, unsigned int sc_reg,
-                           u32 val);
+        int (*scr_read) (struct ata_port *ap, unsigned int sc_reg, u32 *val);
+        int (*scr_write) (struct ata_port *ap, unsigned int sc_reg, u32 val);
 
         int (*port_suspend) (struct ata_port *ap, pm_message_t mesg);
         int (*port_resume) (struct ata_port *ap);