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authorMatwey V. Kornilov <matwey@sai.msu.ru>2014-08-27 12:07:43 +0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-09-23 23:14:28 -0700
commit17891c8a9ea17a11b437c7184f7f04e0ab7be811 (patch)
treea6f4b9fe753793224e130e3e0388f9a3cc5533aa
parent82a82340bab6c251e0705339f60763718eaa2a22 (diff)
parport: parport_pc: Introduce intel_bug_present function.
Put the code to check present of the Intel bug from parport_EPP_supported into new intel_bug_present function. The later also return ECR register to the state it has before function call. Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/parport/parport_pc.c38
1 files changed, 26 insertions, 12 deletions
diff --git a/drivers/parport/parport_pc.c b/drivers/parport/parport_pc.c
index 76ee7750bc5e..fedc06bed18d 100644
--- a/drivers/parport/parport_pc.c
+++ b/drivers/parport/parport_pc.c
@@ -1702,6 +1702,30 @@ static int parport_ECP_supported(struct parport *pb)
}
#endif
+static int intel_bug_present(struct parport *pb)
+{
+ const struct parport_pc_private *priv = pb->private_data;
+ int bug_present = 0;
+
+ if (priv->ecr) {
+ /* store value of ECR */
+ unsigned char ecr = inb(ECONTROL(pb));
+ unsigned char i;
+ for (i = 0x00; i < 0x80; i += 0x20) {
+ ECR_WRITE(pb, i);
+ if (clear_epp_timeout(pb)) {
+ /* Phony EPP in ECP. */
+ bug_present = 1;
+ break;
+ }
+ }
+ /* return ECR into the inital state */
+ ECR_WRITE(pb, ecr);
+ }
+
+ return bug_present;
+}
+
static int parport_ECPPS2_supported(struct parport *pb)
{
const struct parport_pc_private *priv = pb->private_data;
@@ -1722,8 +1746,6 @@ static int parport_ECPPS2_supported(struct parport *pb)
static int parport_EPP_supported(struct parport *pb)
{
- const struct parport_pc_private *priv = pb->private_data;
-
/*
* Theory:
* Bit 0 of STR is the EPP timeout bit, this bit is 0
@@ -1742,16 +1764,8 @@ static int parport_EPP_supported(struct parport *pb)
return 0; /* No way to clear timeout */
/* Check for Intel bug. */
- if (priv->ecr) {
- unsigned char i;
- for (i = 0x00; i < 0x80; i += 0x20) {
- ECR_WRITE(pb, i);
- if (clear_epp_timeout(pb)) {
- /* Phony EPP in ECP. */
- return 0;
- }
- }
- }
+ if (intel_bug_present(pb))
+ return 0;
pb->modes |= PARPORT_MODE_EPP;