[PATCH 1/2] drivers: pata_octeon_cf : Switch IO mode depending on model number

From: Daniel Walker
Date: Fri Jan 08 2016 - 00:28:52 EST


From: Anil Veliyankara Madam <aveliyan@xxxxxxxxx>

Since viking flash has a problem in the MWDMA mode which causes data
corruption, this patch allows the driver to detect the model number
and switch the IO mode to PIO6 if it's a viking flash.

Cc: xe-kernel@xxxxxxxxxxxxxxxxxx
Signed-off-by: Anil Veliyankara Madam <aveliyan@xxxxxxxxx>
Signed-off-by: Shikha Jain <shikjain@xxxxxxxxx>
---
drivers/ata/pata_octeon_cf.c | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/drivers/ata/pata_octeon_cf.c b/drivers/ata/pata_octeon_cf.c
index 2724595..9d05bc9 100644
--- a/drivers/ata/pata_octeon_cf.c
+++ b/drivers/ata/pata_octeon_cf.c
@@ -826,6 +826,30 @@ static unsigned int octeon_cf_qc_issue(struct ata_queued_cmd *qc)
return 0;
}

+static unsigned long octeon_cf_mode_filter(struct ata_device *dev,
+ unsigned long mask)
+{
+ const char viking_model_num[] = "VRFDFC22048UCHC-TE";
+ unsigned char model_num[ATA_ID_PROD_LEN + 1];
+
+ if (dev->class != ATA_DEV_ATA)
+ return mask;
+
+ ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
+ /*
+ * Viking flash with SMI controller causes read errors in
+ * MWDMA modes. Force PIO mode.
+ */
+ if (strncmp(model_num, viking_model_num,
+ strlen(viking_model_num)) == 0) {
+ DPRINTK("Viking flash with SMI controller detected.");
+ DPRINTK("Forcing PIO mode.\n");
+ mask &= ATA_MASK_PIO;
+ }
+
+ return mask;
+}
+
static struct ata_port_operations octeon_cf_ops = {
.inherits = &ata_sff_port_ops,
.check_atapi_dma = octeon_cf_check_atapi_dma,
@@ -835,6 +859,7 @@ static struct ata_port_operations octeon_cf_ops = {
.sff_irq_on = octeon_cf_ata_port_noaction,
.sff_irq_clear = octeon_cf_ata_port_noaction,
.cable_detect = ata_cable_40wire,
+ .mode_filter = octeon_cf_mode_filter,
.set_piomode = octeon_cf_set_piomode,
.set_dmamode = octeon_cf_set_dmamode,
.dev_config = octeon_cf_dev_config,
--
2.1.4