[PATCH AUTOSEL 6.5 24/31] ata: pata_parport: add custom version of wait_after_reset

[PATCH AUTOSEL 6.5 24/31] ata: pata_parport: add custom version of wait_after_reset

[Sasha Levin]

From: Ondrej Zary <linux@zary.sk>

[ Upstream commit f343e578fef99a69b3322aca38b94a6d8ded2ce7 ]

Some parallel adapters (e.g. EXP Computer MC-1285B EPP Cable) return
bogus values when there's no master device present. This can cause
reset to fail, preventing the lone slave device (such as EXP Computer
CD-865) from working.

Add custom version of wait_after_reset that ignores master failure when
a slave device is present. The custom version is also needed because
the generic ata_sff_wait_after_reset uses direct port I/O for slave
device detection.

Signed-off-by: Ondrej Zary <linux@zary.sk>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/ata/pata_parport/pata_parport.c | 68 ++++++++++++++++++++++++-
 1 file changed, 67 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/pata_parport/pata_parport.c b/drivers/ata/pata_parport/pata_parport.c
index 1af64d435d3c2..cd5463970be2e 100644
--- a/drivers/ata/pata_parport/pata_parport.c
+++ b/drivers/ata/pata_parport/pata_parport.c
@@ -73,6 +73,72 @@ static bool pata_parport_devchk(struct ata_port *ap, unsigned int device)
 	return (nsect == 0x55) && (lbal == 0xaa);
 }
 
+static int pata_parport_wait_after_reset(struct ata_link *link,
+					 unsigned int devmask,
+					 unsigned long deadline)
+{
+	struct ata_port *ap = link->ap;
+	struct pi_adapter *pi = ap->host->private_data;
+	unsigned int dev0 = devmask & (1 << 0);
+	unsigned int dev1 = devmask & (1 << 1);
+	int rc, ret = 0;
+
+	ata_msleep(ap, ATA_WAIT_AFTER_RESET);
+
+	/* always check readiness of the master device */
+	rc = ata_sff_wait_ready(link, deadline);
+	if (rc) {
+		/*
+		 * some adapters return bogus values if master device is not
+		 * present, so don't abort now if a slave device is present
+		 */
+		if (!dev1)
+			return rc;
+		ret = -ENODEV;
+	}
+
+	/*
+	 * if device 1 was found in ata_devchk, wait for register
+	 * access briefly, then wait for BSY to clear.
+	 */
+	if (dev1) {
+		int i;
+
+		pata_parport_dev_select(ap, 1);
+
+		/*
+		 * Wait for register access.  Some ATAPI devices fail
+		 * to set nsect/lbal after reset, so don't waste too
+		 * much time on it.  We're gonna wait for !BSY anyway.
+		 */
+		for (i = 0; i < 2; i++) {
+			u8 nsect, lbal;
+
+			nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
+			lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
+			if (nsect == 1 && lbal == 1)
+				break;
+			/* give drive a breather */
+			ata_msleep(ap, 50);
+		}
+
+		rc = ata_sff_wait_ready(link, deadline);
+		if (rc) {
+			if (rc != -ENODEV)
+				return rc;
+			ret = rc;
+		}
+	}
+
+	pata_parport_dev_select(ap, 0);
+	if (dev1)
+		pata_parport_dev_select(ap, 1);
+	if (dev0)
+		pata_parport_dev_select(ap, 0);
+
+	return ret;
+}
+
 static int pata_parport_bus_softreset(struct ata_port *ap, unsigned int devmask,
 				      unsigned long deadline)
 {
@@ -87,7 +153,7 @@ static int pata_parport_bus_softreset(struct ata_port *ap, unsigned int devmask,
 	ap->last_ctl = ap->ctl;
 
 	/* wait the port to become ready */
-	return ata_sff_wait_after_reset(&ap->link, devmask, deadline);
+	return pata_parport_wait_after_reset(&ap->link, devmask, deadline);
 }
 
 static int pata_parport_softreset(struct ata_link *link, unsigned int *classes,
-- 
2.40.1

[PATCH AUTOSEL 6.5 25/31] ata: pata_parport: fit3: implement IDE command set registers

[Sasha Levin]

From: Ondrej Zary <linux@zary.sk>

[ Upstream commit 0c1e81d0b5ebd5813536dd5fcf5966ad043f37dc ]

fit3 protocol driver does not support accessing IDE control registers
(device control/altstatus). The DOS driver does not use these registers
either (as observed from DOSEMU trace). But the HW seems to be capable
of accessing these registers - I simply tried bit 3 and it works!

The control register is required to properly reset ATAPI devices or
they will be detected only once (after a power cycle).

Tested with EXP Computer CD-865 with MC-1285B EPP cable and
TransDisk 3000.

Signed-off-by: Ondrej Zary <linux@zary.sk>
Reviewed-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/ata/pata_parport/fit3.c | 14 ++------------
 1 file changed, 2 insertions(+), 12 deletions(-)

diff --git a/drivers/ata/pata_parport/fit3.c b/drivers/ata/pata_parport/fit3.c
index bad7aa920cdca..d2b81cf2e16d2 100644
--- a/drivers/ata/pata_parport/fit3.c
+++ b/drivers/ata/pata_parport/fit3.c
@@ -9,11 +9,6 @@
  *
  * The TD-2000 and certain older devices use a different protocol.
  * Try the fit2 protocol module with them.
- *
- * NB:  The FIT adapters do not appear to support the control
- * registers.  So, we map ALT_STATUS to STATUS and NO-OP writes
- * to the device control register - this means that IDE reset
- * will not work on these devices.
  */
 
 #include <linux/module.h>
@@ -37,8 +32,7 @@
 
 static void fit3_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
 {
-	if (cont == 1)
-		return;
+	regr += cont << 3;
 
 	switch (pi->mode) {
 	case 0:
@@ -59,11 +53,7 @@ static int fit3_read_regr(struct pi_adapter *pi, int cont, int regr)
 {
 	int  a, b;
 
-	if (cont) {
-		if (regr != 6)
-			return 0xff;
-		regr = 7;
-	}
+	regr += cont << 3;
 
 	switch (pi->mode) {
 	case 0:
-- 
2.40.1