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, 15 insertions, 10 deletions

diff --git a/drivers/ata/sata_promise.c b/drivers/ata/sata_promise.c
index d2fcb9a6bec2..d39ebc23c4a9 100644
--- a/drivers/ata/sata_promise.c
+++ b/drivers/ata/sata_promise.c
@@ -128,8 +128,8 @@ struct pdc_port_priv {
         dma_addr_t              pkt_dma;
 };
 
-static u32 pdc_sata_scr_read (struct ata_port *ap, unsigned int sc_reg);
-static void pdc_sata_scr_write (struct ata_port *ap, unsigned int sc_reg, u32 val);
+static int pdc_sata_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val);
+static int pdc_sata_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val);
 static int pdc_ata_init_one (struct pci_dev *pdev, const struct pci_device_id *ent);
 static int pdc_common_port_start(struct ata_port *ap);
 static int pdc_sata_port_start(struct ata_port *ap);
@@ -427,19 +427,20 @@ static int pdc_sata_cable_detect(struct ata_port *ap)
         return ATA_CBL_SATA;
 }
 
-static u32 pdc_sata_scr_read (struct ata_port *ap, unsigned int sc_reg)
+static int pdc_sata_scr_read(struct ata_port *ap, unsigned int sc_reg, u32 *val)
 {
         if (sc_reg > SCR_CONTROL)
-                return 0xffffffffU;
-        return readl(ap->ioaddr.scr_addr + (sc_reg * 4));
+                return -EINVAL;
+        *val = readl(ap->ioaddr.scr_addr + (sc_reg * 4));
+        return 0;
 }
 
-static void pdc_sata_scr_write (struct ata_port *ap, unsigned int sc_reg,
-                               u32 val)
+static int pdc_sata_scr_write(struct ata_port *ap, unsigned int sc_reg, u32 val)
 {
         if (sc_reg > SCR_CONTROL)
-                return;
+                return -EINVAL;
         writel(val, ap->ioaddr.scr_addr + (sc_reg * 4));
+        return 0;
 }
 
 static void pdc_atapi_pkt(struct ata_queued_cmd *qc)
@@ -642,8 +643,12 @@ static void pdc_error_intr(struct ata_port *ap, struct ata_queued_cmd *qc,
                            | PDC_PCI_SYS_ERR | PDC1_PCI_PARITY_ERR))
                 ac_err_mask |= AC_ERR_HOST_BUS;
 
-        if (sata_scr_valid(ap))
-                ehi->serror |= pdc_sata_scr_read(ap, SCR_ERROR);
+        if (sata_scr_valid(ap)) {
+                u32 serror;
+
+                pdc_sata_scr_read(ap, SCR_ERROR, &serror);
+                ehi->serror |= serror;
+        }
 
         qc->err_mask |= ac_err_mask;