[Linux-parport] [PATCH] scsi: imm: Add a module parameter for the transfer mode
Alex Henrie
alexhenrie24 at gmail.com
Wed Aug 30 22:23:48 PDT 2023
Fix in the imm driver the same problem that was fixed in the ppa driver
by commit 68a4f84a17c1 ("scsi: ppa: Add a module parameter for the
transfer mode").
Tested and confirmed working with an Iomega Z250P zip drive and a
StarTech PEX1P2 AX99100 PCIe parallel port.
Signed-off-by: Alex Henrie <alexhenrie24 at gmail.com>
---
drivers/scsi/Kconfig | 15 ----------
drivers/scsi/imm.c | 70 +++++++++++++++++++++++---------------------
drivers/scsi/imm.h | 4 ---
3 files changed, 37 insertions(+), 52 deletions(-)
diff --git a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
index 695a57d894cd..addac7fbe37b 100644
--- a/drivers/scsi/Kconfig
+++ b/drivers/scsi/Kconfig
@@ -834,21 +834,6 @@ config SCSI_IMM
To compile this driver as a module, choose M here: the
module will be called imm.
-config SCSI_IZIP_EPP16
- bool "ppa/imm option - Use slow (but safe) EPP-16"
- depends on SCSI_IMM
- help
- EPP (Enhanced Parallel Port) is a standard for parallel ports which
- allows them to act as expansion buses that can handle up to 64
- peripheral devices.
-
- Some parallel port chipsets are slower than their motherboard, and
- so we have to control the state of the chipset's FIFO queue every
- now and then to avoid data loss. This will be done if you say Y
- here.
-
- Generally, saying Y is the safe option and slows things down a bit.
-
config SCSI_IZIP_SLOW_CTR
bool "ppa/imm option - Assume slow parport control register"
depends on SCSI_PPA || SCSI_IMM
diff --git a/drivers/scsi/imm.c b/drivers/scsi/imm.c
index 07db98161a03..180a5ddedb2c 100644
--- a/drivers/scsi/imm.c
+++ b/drivers/scsi/imm.c
@@ -51,10 +51,15 @@ typedef struct {
} imm_struct;
static void imm_reset_pulse(unsigned int base);
-static int device_check(imm_struct *dev);
+static int device_check(imm_struct *dev, bool autodetect);
#include "imm.h"
+static unsigned int mode = IMM_AUTODETECT;
+module_param(mode, uint, 0644);
+MODULE_PARM_DESC(mode, "Transfer mode (0 = Autodetect, 1 = SPP 4-bit, "
+ "2 = SPP 8-bit, 3 = EPP 8-bit, 4 = EPP 16-bit, 5 = EPP 32-bit");
+
static inline imm_struct *imm_dev(struct Scsi_Host *host)
{
return *(imm_struct **)&host->hostdata;
@@ -366,13 +371,10 @@ static int imm_out(imm_struct *dev, char *buffer, int len)
case IMM_EPP_8:
epp_reset(ppb);
w_ctr(ppb, 0x4);
-#ifdef CONFIG_SCSI_IZIP_EPP16
- if (!(((long) buffer | len) & 0x01))
- outsw(ppb + 4, buffer, len >> 1);
-#else
- if (!(((long) buffer | len) & 0x03))
+ if (dev->mode == IMM_EPP_32 && !(((long) buffer | len) & 0x03))
outsl(ppb + 4, buffer, len >> 2);
-#endif
+ else if (dev->mode == IMM_EPP_16 && !(((long) buffer | len) & 0x01))
+ outsw(ppb + 4, buffer, len >> 1);
else
outsb(ppb + 4, buffer, len);
w_ctr(ppb, 0xc);
@@ -426,13 +428,10 @@ static int imm_in(imm_struct *dev, char *buffer, int len)
case IMM_EPP_8:
epp_reset(ppb);
w_ctr(ppb, 0x24);
-#ifdef CONFIG_SCSI_IZIP_EPP16
- if (!(((long) buffer | len) & 0x01))
- insw(ppb + 4, buffer, len >> 1);
-#else
- if (!(((long) buffer | len) & 0x03))
- insl(ppb + 4, buffer, len >> 2);
-#endif
+ if (dev->mode == IMM_EPP_32 && !(((long) buffer | len) & 0x03))
+ insw(ppb + 4, buffer, len >> 2);
+ else if (dev->mode == IMM_EPP_16 && !(((long) buffer | len) & 0x01))
+ insl(ppb + 4, buffer, len >> 1);
else
insb(ppb + 4, buffer, len);
w_ctr(ppb, 0x2c);
@@ -589,13 +588,28 @@ static int imm_select(imm_struct *dev, int target)
static int imm_init(imm_struct *dev)
{
+ bool autodetect = dev->mode == IMM_AUTODETECT;
+
+ if (autodetect) {
+ int modes = dev->dev->port->modes;
+
+ /* Mode detection works up the chain of speed
+ * This avoids a nasty if-then-else-if-... tree
+ */
+ dev->mode = IMM_NIBBLE;
+
+ if (modes & PARPORT_MODE_TRISTATE)
+ dev->mode = IMM_PS2;
+ }
+
if (imm_connect(dev, 0) != 1)
return -EIO;
imm_reset_pulse(dev->base);
mdelay(1); /* Delay to allow devices to settle */
imm_disconnect(dev);
mdelay(1); /* Another delay to allow devices to settle */
- return device_check(dev);
+
+ return device_check(dev, autodetect);
}
static inline int imm_send_command(struct scsi_cmnd *cmd)
@@ -1000,7 +1014,7 @@ static int imm_reset(struct scsi_cmnd *cmd)
return SUCCESS;
}
-static int device_check(imm_struct *dev)
+static int device_check(imm_struct *dev, bool autodetect)
{
/* This routine looks for a device and then attempts to use EPP
to send a command. If all goes as planned then EPP is available. */
@@ -1012,8 +1026,8 @@ static int device_check(imm_struct *dev)
old_mode = dev->mode;
for (loop = 0; loop < 8; loop++) {
/* Attempt to use EPP for Test Unit Ready */
- if ((ppb & 0x0007) == 0x0000)
- dev->mode = IMM_EPP_32;
+ if (autodetect && (ppb & 0x0007) == 0x0000)
+ dev->mode = IMM_EPP_8;
second_pass:
imm_connect(dev, CONNECT_EPP_MAYBE);
@@ -1038,7 +1052,7 @@ static int device_check(imm_struct *dev)
udelay(1000);
imm_disconnect(dev);
udelay(1000);
- if (dev->mode == IMM_EPP_32) {
+ if (dev->mode != old_mode) {
dev->mode = old_mode;
goto second_pass;
}
@@ -1063,7 +1077,7 @@ static int device_check(imm_struct *dev)
udelay(1000);
imm_disconnect(dev);
udelay(1000);
- if (dev->mode == IMM_EPP_32) {
+ if (dev->mode != old_mode) {
dev->mode = old_mode;
goto second_pass;
}
@@ -1150,7 +1164,6 @@ static int __imm_attach(struct parport *pb)
DECLARE_WAIT_QUEUE_HEAD_ONSTACK(waiting);
DEFINE_WAIT(wait);
int ports;
- int modes, ppb;
int err = -ENOMEM;
struct pardev_cb imm_cb;
@@ -1162,7 +1175,7 @@ static int __imm_attach(struct parport *pb)
dev->base = -1;
- dev->mode = IMM_AUTODETECT;
+ dev->mode = mode < IMM_UNKNOWN ? mode : IMM_AUTODETECT;
INIT_LIST_HEAD(&dev->list);
temp = find_parent();
@@ -1197,18 +1210,9 @@ static int __imm_attach(struct parport *pb)
}
dev->waiting = NULL;
finish_wait(&waiting, &wait);
- ppb = dev->base = dev->dev->port->base;
+ dev->base = dev->dev->port->base;
dev->base_hi = dev->dev->port->base_hi;
- w_ctr(ppb, 0x0c);
- modes = dev->dev->port->modes;
-
- /* Mode detection works up the chain of speed
- * This avoids a nasty if-then-else-if-... tree
- */
- dev->mode = IMM_NIBBLE;
-
- if (modes & PARPORT_MODE_TRISTATE)
- dev->mode = IMM_PS2;
+ w_ctr(dev->base, 0x0c);
/* Done configuration */
diff --git a/drivers/scsi/imm.h b/drivers/scsi/imm.h
index 411cf94af5b0..398fa5b15181 100644
--- a/drivers/scsi/imm.h
+++ b/drivers/scsi/imm.h
@@ -100,11 +100,7 @@ static char *IMM_MODE_STRING[] =
[IMM_PS2] = "PS/2",
[IMM_EPP_8] = "EPP 8 bit",
[IMM_EPP_16] = "EPP 16 bit",
-#ifdef CONFIG_SCSI_IZIP_EPP16
- [IMM_EPP_32] = "EPP 16 bit",
-#else
[IMM_EPP_32] = "EPP 32 bit",
-#endif
[IMM_UNKNOWN] = "Unknown",
};
--
2.42.0
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