Several fixes for the AVR32 PATA driver

Several fixes for the AVR32 PATA driver:

* Updated to use new AVR32 SMC timing API. This removes the need for "magic"
constants in signal timing.

* Removed the ATA_FLAG_PIO_POLLING, the driver should use interrupts.

* Removed .port_disable and .irq_ack as these are no longer needed.

* Improved some comments.

Signed-off-by: Kristoffer Nyborg Gregertsen <kngregertsen@norway.atmel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 33 insertions, 28 deletions

diff --git a/drivers/ata/pata_at32.c b/drivers/ata/pata_at32.c
index bb250a48e27c..67e574de31e8 100644
--- a/drivers/ata/pata_at32.c
+++ b/drivers/ata/pata_at32.c
@@ -28,7 +28,7 @@
 #include <asm/arch/smc.h>
 
 #define DRV_NAME "pata_at32"
-#define DRV_VERSION "0.0.2"
+#define DRV_VERSION "0.0.3"
 
 /*
  * CompactFlash controller memory layout relative to the base address:
@@ -64,6 +64,8 @@
  *      Mode 2  | 8.3   | 240 ns         | 0x07
  *      Mode 3  | 11.1  | 180 ns         | 0x0f
  *      Mode 4  | 16.7  | 120 ns         | 0x1f
+ *
+ * Alter PIO_MASK below according to table to set maximal PIO mode.
  */
 #define PIO_MASK (0x1f)
 
@@ -85,36 +87,40 @@ struct at32_ide_info {
  */
 static int pata_at32_setup_timing(struct device *dev,
                                   struct at32_ide_info *info,
-                                  const struct ata_timing *timing)
+                                  const struct ata_timing *ata)
 {
-        /* These two values are found through testing */
-        const int min_recover = 25;
-        const int ncs_hold    = 15;
-
         struct smc_config *smc = &info->smc;
+        struct smc_timing timing;
 
         int active;
         int recover;
 
+        memset(&timing, 0, sizeof(struct smc_timing));
+
         /* Total cycle time */
-        smc->read_cycle = timing->cyc8b;
+        timing.read_cycle  = ata->cyc8b;
 
         /* DIOR <= CFIOR timings */
-        smc->nrd_setup = timing->setup;
-        smc->nrd_pulse = timing->act8b;
+        timing.nrd_setup   = ata->setup;
+        timing.nrd_pulse   = ata->act8b;
+        timing.nrd_recover = ata->rec8b;
+
+        /* Convert nanosecond timing to clock cycles */
+        smc_set_timing(smc, &timing);
 
-        /* Compute recover, extend total cycle if needed */
-        active  = smc->nrd_setup + smc->nrd_pulse;
+        /* Add one extra cycle setup due to signal ring */
+        smc->nrd_setup = smc->nrd_setup + 1;
+
+        active  = smc->nrd_setup + smc->nrd_pulse;
         recover = smc->read_cycle - active;
 
-        if (recover < min_recover) {
-                smc->read_cycle = active + min_recover;
-                recover = min_recover;
-        }
+        /* Need at least two cycles recovery */
+        if (recover < 2)
+          smc->read_cycle = active + 2;
 
         /* (CS0, CS1, DIR, OE) <= (CFCE1, CFCE2, CFRNW, NCSX) timings */
-        smc->ncs_read_setup  = 0;
-        smc->ncs_read_pulse  = active + ncs_hold;
+        smc->ncs_read_setup = 1;
+        smc->ncs_read_pulse = smc->read_cycle - 2;
 
         /* Write timings same as read timings */
         smc->write_cycle = smc->read_cycle;
@@ -123,11 +129,13 @@ static int pata_at32_setup_timing(struct device *dev,
         smc->ncs_write_setup = smc->ncs_read_setup;
         smc->ncs_write_pulse = smc->ncs_read_pulse;
 
-        /* Do some debugging output */
-        dev_dbg(dev, "SMC: C=%d S=%d P=%d R=%d NCSS=%d NCSP=%d NCSR=%d\n",
+        /* Do some debugging output of ATA and SMC timings */
+        dev_dbg(dev, "ATA: C=%d S=%d P=%d R=%d\n",
+                ata->cyc8b, ata->setup, ata->act8b, ata->rec8b);
+
+        dev_dbg(dev, "SMC: C=%d S=%d P=%d NS=%d NP=%d\n",
                 smc->read_cycle, smc->nrd_setup, smc->nrd_pulse,
-                recover, smc->ncs_read_setup, smc->ncs_read_pulse,
-                smc->read_cycle - smc->ncs_read_pulse);
+                smc->ncs_read_setup, smc->ncs_read_pulse);
 
         /* Finally, configure the SMC */
         return smc_set_configuration(info->cs, smc);
@@ -182,7 +190,6 @@ static struct scsi_host_template at32_sht = {
 };
 
 static struct ata_port_operations at32_port_ops = {
-        .port_disable           = ata_port_disable,
         .set_piomode            = pata_at32_set_piomode,
         .tf_load                = ata_tf_load,
         .tf_read                = ata_tf_read,
@@ -203,7 +210,6 @@ static struct ata_port_operations at32_port_ops = {
 
         .irq_clear              = pata_at32_irq_clear,
         .irq_on                 = ata_irq_on,
-        .irq_ack                = ata_irq_ack,
 
         .port_start             = ata_sff_port_start,
 };
@@ -223,8 +229,7 @@ static int __init pata_at32_init_one(struct device *dev,
         /* Setup ATA bindings */
         ap->ops      = &at32_port_ops;
         ap->pio_mask = PIO_MASK;
-        ap->flags    = ATA_FLAG_MMIO | ATA_FLAG_SLAVE_POSS
-                | ATA_FLAG_PIO_POLLING;
+        ap->flags   |= ATA_FLAG_MMIO | ATA_FLAG_SLAVE_POSS;
 
         /*
          * Since all 8-bit taskfile transfers has to go on the lower
@@ -357,12 +362,12 @@ static int __init pata_at32_probe(struct platform_device *pdev)
         info->smc.tdf_mode       = 0; /* TDF optimization disabled */
         info->smc.tdf_cycles     = 0; /* No TDF wait cycles */
 
-        /* Setup ATA timing */
+        /* Setup SMC to ATA timing */
         ret = pata_at32_setup_timing(dev, info, &initial_timing);
         if (ret)
                 goto err_setup_timing;
 
-        /* Setup ATA addresses */
+        /* Map ATA address space */
         ret = -ENOMEM;
         info->ide_addr = devm_ioremap(dev, info->res_ide.start, 16);
         info->alt_addr = devm_ioremap(dev, info->res_alt.start, 16);
@@ -373,7 +378,7 @@ static int __init pata_at32_probe(struct platform_device *pdev)
         pata_at32_debug_bus(dev, info);
 #endif
 
-        /* Register ATA device */
+        /* Setup and register ATA device */
         ret = pata_at32_init_one(dev, info);
         if (ret)
                 goto err_ata_device;