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Date: Fri, 18 Jul 2014 11:12:54 +0400 From: matwey@....msu.ru To: gregkh@...uxfoundation.org Cc: linux-kernel@...r.kernel.org, linux-parport@...ts.infradead.org, hsommer@....org, gnomes@...rguk.ukuu.org.uk, matwey.kornilov@...il.com, "Matwey V. Kornilov" <matwey@....msu.ru> Subject: [PATCHv4 1/2] parport: parport_pc: Introduce intel_bug_present function. From: "Matwey V. Kornilov" <matwey@....msu.ru> 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. Suggested-by: One Thousand Gnomes <gnomes@...rguk.ukuu.org.uk> Tested-by: Heiko Andreas Sommer <hsommer@....org> Signed-off-by: Matwey V. Kornilov <matwey@....msu.ru> --- drivers/parport/parport_pc.c | 38 ++++++++++++++++++++++++++------------ 1 file changed, 26 insertions(+), 12 deletions(-) diff --git a/drivers/parport/parport_pc.c b/drivers/parport/parport_pc.c index 76ee775..a6eaafb 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; -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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