libata: make reset related methods proper port operations

Currently reset methods are not specified directly in the
ata_port_operations table.  If a LLD wants to use custom reset
methods, it should construct and use a error_handler which uses those
reset methods.  It's done this way for two reasons.

First, the ops table already contained too many methods and adding
four more of them would noticeably increase the amount of necessary
boilerplate code all over low level drivers.

Second, as ->error_handler uses those reset methods, it can get
confusing.  ie. By overriding ->error_handler, those reset ops can be
made useless making layering a bit hazy.

Now that ops table uses inheritance, the first problem doesn't exist
anymore.  The second isn't completely solved but is relieved by
providing default values - most drivers can just override what it has
implemented and don't have to concern itself about higher level
callbacks.  In fact, there currently is no driver which actually
modifies error handling behavior.  Drivers which override
->error_handler just wraps the standard error handler only to prepare
the controller for EH.  I don't think making ops layering strict has
any noticeable benefit.

This patch makes ->prereset, ->softreset, ->hardreset, ->postreset and
their PMP counterparts propoer ops.  Default ops are provided in the
base ops tables and drivers are converted to override individual reset
methods instead of creating custom error_handler.

* ata_std_error_handler() doesn't use sata_std_hardreset() if SCRs
  aren't accessible.  sata_promise doesn't need to use separate
  error_handlers for PATA and SATA anymore.

* softreset is broken for sata_inic162x and sata_sx4.  As libata now
  always prefers hardreset, this doesn't really matter but the ops are
  forced to NULL using ATA_OP_NULL for documentation purpose.

* pata_hpt374 needs to use different prereset for the first and second
  PCI functions.  This used to be done by branching from
  hpt374_error_handler().  The proper way to do this is to use
  separate ops and port_info tables for each function.  Converted.

Signed-off-by: Tejun Heo <htejun@gmail.com>

1 files changed, 20 insertions, 41 deletions

diff --git a/drivers/ata/pata_hpt37x.c b/drivers/ata/pata_hpt37x.c
index fb37e3a161fc..c10fcd31418d 100644
--- a/drivers/ata/pata_hpt37x.c
+++ b/drivers/ata/pata_hpt37x.c
@@ -341,19 +341,7 @@ static int hpt37x_pre_reset(struct ata_link *link, unsigned long deadline)
         return ata_std_prereset(link, deadline);
 }
 
-/**
- *      hpt37x_error_handler    -       reset the hpt374
- *      @ap: ATA port to reset
- *
- *      Perform probe for HPT37x, except for HPT374 channel 2
- */
-
-static void hpt37x_error_handler(struct ata_port *ap)
-{
-        ata_bmdma_drive_eh(ap, hpt37x_pre_reset, ata_std_softreset, NULL, ata_std_postreset);
-}
-
-static int hpt374_pre_reset(struct ata_link *link, unsigned long deadline)
+static int hpt374_fn1_pre_reset(struct ata_link *link, unsigned long deadline)
 {
         static const struct pci_bits hpt37x_enable_bits[] = {
                 { 0x50, 1, 0x04, 0x04 },
@@ -390,25 +378,6 @@ static int hpt374_pre_reset(struct ata_link *link, unsigned long deadline)
 }
 
 /**
- *      hpt374_error_handler    -       reset the hpt374
- *      @classes:
- *
- *      The 374 cable detect is a little different due to the extra
- *      channels. The function 0 channels work like usual but function 1
- *      is special
- */
-
-static void hpt374_error_handler(struct ata_port *ap)
-{
-        struct pci_dev *pdev = to_pci_dev(ap->host->dev);
-
-        if (!(PCI_FUNC(pdev->devfn) & 1))
-                hpt37x_error_handler(ap);
-        else
-                ata_bmdma_drive_eh(ap, hpt374_pre_reset, ata_std_softreset, NULL, ata_std_postreset);
-}
-
-/**
  *      hpt370_set_piomode              -       PIO setup
  *      @ap: ATA interface
  *      @adev: device on the interface
@@ -635,7 +604,7 @@ static struct ata_port_operations hpt370_port_ops = {
         .mode_filter    = hpt370_filter,
         .set_piomode    = hpt370_set_piomode,
         .set_dmamode    = hpt370_set_dmamode,
-        .error_handler  = hpt37x_error_handler,
+        .prereset       = hpt37x_pre_reset,
 };
 
 /*
@@ -659,17 +628,17 @@ static struct ata_port_operations hpt372_port_ops = {
 
         .set_piomode    = hpt372_set_piomode,
         .set_dmamode    = hpt372_set_dmamode,
-        .error_handler  = hpt37x_error_handler,
+        .prereset       = hpt37x_pre_reset,
 };
 
 /*
  *      Configuration for HPT374. Mode setting works like 372 and friends
- *      but we have a different cable detection procedure.
+ *      but we have a different cable detection procedure for function 1.
  */
 
-static struct ata_port_operations hpt374_port_ops = {
+static struct ata_port_operations hpt374_fn1_port_ops = {
         .inherits       = &hpt372_port_ops,
-        .error_handler  = hpt374_error_handler,
+        .prereset       = hpt374_fn1_pre_reset,
 };
 
 /**
@@ -821,13 +790,20 @@ static int hpt37x_init_one(struct pci_dev *dev, const struct pci_device_id *id)
                 .udma_mask = ATA_UDMA6,
                 .port_ops = &hpt372_port_ops
         };
-        /* HPT374 - UDMA100 */
-        static const struct ata_port_info info_hpt374 = {
+        /* HPT374 - UDMA100, function 1 uses different prereset method */
+        static const struct ata_port_info info_hpt374_fn0 = {
+                .flags = ATA_FLAG_SLAVE_POSS,
+                .pio_mask = 0x1f,
+                .mwdma_mask = 0x07,
+                .udma_mask = ATA_UDMA5,
+                .port_ops = &hpt372_port_ops
+        };
+        static const struct ata_port_info info_hpt374_fn1 = {
                 .flags = ATA_FLAG_SLAVE_POSS,
                 .pio_mask = 0x1f,
                 .mwdma_mask = 0x07,
                 .udma_mask = ATA_UDMA5,
-                .port_ops = &hpt374_port_ops
+                .port_ops = &hpt374_fn1_port_ops
         };
 
         static const int MHz[4] = { 33, 40, 50, 66 };
@@ -912,7 +888,10 @@ static int hpt37x_init_one(struct pci_dev *dev, const struct pci_device_id *id)
                                 break;
                         case PCI_DEVICE_ID_TTI_HPT374:
                                 chip_table = &hpt374;
-                                ppi[0] = &info_hpt374;
+                                if (!(PCI_FUNC(dev->devfn) & 1))
+                                        *ppi = &info_hpt374_fn0;
+                                else
+                                        *ppi = &info_hpt374_fn1;
                                 break;
                         default:
                                 printk(KERN_ERR "pata_hpt37x: PCI table is bogus please report (%d).\n", dev->device);