[PATCH 05/16] pata_parport: add comm protocol driver
From: Ondrej Zary
Date: Sat Mar 05 2022 - 15:15:02 EST
Add DataStor Commuter protocol driver.
Signed-off-by: Ondrej Zary <linux@xxxxxxx>
---
drivers/ata/pata_parport/Kconfig | 10 ++
drivers/ata/pata_parport/Makefile | 1 +
drivers/ata/pata_parport/comm.c | 198 ++++++++++++++++++++++++++++++
3 files changed, 209 insertions(+)
create mode 100644 drivers/ata/pata_parport/comm.c
diff --git a/drivers/ata/pata_parport/Kconfig b/drivers/ata/pata_parport/Kconfig
index e88d9c0bedc6..3cc3d6ae4d45 100644
--- a/drivers/ata/pata_parport/Kconfig
+++ b/drivers/ata/pata_parport/Kconfig
@@ -54,3 +54,13 @@ config PATA_PARPORT_BPCK6
answer Y here to build in the protocol driver, otherwise you should
answer M to build it as a loadable module. The module will be
called bpck6.
+
+config PATA_PARPORT_COMM
+ tristate "DataStor Commuter protocol"
+ depends on PATA_PARPORT
+ help
+ This option enables support for the Commuter parallel port IDE
+ protocol from DataStor. If you chose to build PATA_PARPORT support
+ into your kernel, you may answer Y here to build in the protocol
+ driver, otherwise you should answer M to build it as a loadable
+ module. The module will be called comm.
diff --git a/drivers/ata/pata_parport/Makefile b/drivers/ata/pata_parport/Makefile
index 60522279aa16..fcb77a855ef6 100644
--- a/drivers/ata/pata_parport/Makefile
+++ b/drivers/ata/pata_parport/Makefile
@@ -10,3 +10,4 @@ obj-$(CONFIG_PATA_PARPORT) += pata_parport.o
obj-$(CONFIG_PATA_PARPORT_ATEN) += aten.o
obj-$(CONFIG_PATA_PARPORT_BPCK) += bpck.o
obj-$(CONFIG_PATA_PARPORT_BPCK6) += bpck6.o
+obj-$(CONFIG_PATA_PARPORT_COMM) += comm.o
diff --git a/drivers/ata/pata_parport/comm.c b/drivers/ata/pata_parport/comm.c
new file mode 100644
index 000000000000..cca67e15b498
--- /dev/null
+++ b/drivers/ata/pata_parport/comm.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * comm.c (c) 1997-8 Grant R. Guenther <grant@xxxxxxxxxx>
+ * Under the terms of the GNU General Public License.
+ *
+ * comm.c is a low-level protocol driver for some older models
+ * of the DataStor "Commuter" parallel to IDE adapter. Some of
+ * the parallel port devices marketed by Arista currently
+ * use this adapter.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/wait.h>
+#include <linux/io.h>
+
+#include "pata_parport.h"
+
+/* mode codes: 0 nybble reads, 8-bit writes
+ * 1 8-bit reads and writes
+ * 2 8-bit EPP mode
+ */
+
+#define j44(a, b) (((a >> 3) & 0x0f) | ((b << 1) & 0xf0))
+
+#define P1 do { w2(5); w2(0xd); w2(0xd); w2(5); w2(4); } while (0)
+#define P2 do { w2(5); w2(7); w2(7); w2(5); w2(4); } while (0)
+
+/* cont = 0 - access the IDE register file
+ * cont = 1 - access the IDE command set
+ */
+
+static int cont_map[2] = { 0x08, 0x10 };
+
+static int comm_read_regr(struct pi_adapter *pi, int cont, int regr)
+{
+ int l, h, r;
+
+ r = regr + cont_map[cont];
+
+ switch (pi->mode) {
+ case 0:
+ w0(r); P1; w0(0);
+ w2(6); l = r1(); w0(0x80); h = r1(); w2(4);
+ return j44(l, h);
+ case 1:
+ w0(r+0x20); P1;
+ w0(0); w2(0x26); h = r0(); w2(4);
+ return h;
+ case 2:
+ case 3:
+ case 4:
+ w3(r+0x20); (void)r1();
+ w2(0x24); h = r4(); w2(4);
+ return h;
+ }
+ return -1;
+}
+
+static void comm_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
+{
+ int r = regr + cont_map[cont];
+
+ switch (pi->mode) {
+ case 0:
+ case 1:
+ w0(r); P1; w0(val); P2;
+ break;
+ case 2:
+ case 3:
+ case 4:
+ w3(r); (void)r1(); w4(val);
+ break;
+ }
+}
+
+static void comm_connect(struct pi_adapter *pi)
+{
+ pi->saved_r0 = r0();
+ pi->saved_r2 = r2();
+ w2(4); w0(0xff); w2(6);
+ w2(4); w0(0xaa); w2(6);
+ w2(4); w0(0x00); w2(6);
+ w2(4); w0(0x87); w2(6);
+ w2(4); w0(0xe0); w2(0xc); w2(0xc); w2(4);
+}
+
+static void comm_disconnect(struct pi_adapter *pi)
+{
+ w2(0); w2(0); w2(0); w2(4);
+ w0(pi->saved_r0);
+ w2(pi->saved_r2);
+}
+
+static void comm_read_block(struct pi_adapter *pi, char *buf, int count)
+{
+ int i, l, h;
+
+ switch (pi->mode) {
+ case 0:
+ w0(0x48); P1;
+ for (i = 0; i < count; i++) {
+ w0(0); w2(6); l = r1();
+ w0(0x80); h = r1(); w2(4);
+ buf[i] = j44(l, h);
+ }
+ break;
+ case 1:
+ w0(0x68); P1; w0(0);
+ for (i = 0; i < count; i++) {
+ w2(0x26); buf[i] = r0(); w2(0x24);
+ }
+ w2(4);
+ break;
+ case 2:
+ w3(0x68); (void)r1(); w2(0x24);
+ for (i = 0; i < count; i++)
+ buf[i] = r4();
+ w2(4);
+ break;
+ case 3:
+ w3(0x68); (void)r1(); w2(0x24);
+ for (i = 0; i < count / 2; i++)
+ ((u16 *)buf)[i] = r4w();
+ w2(4);
+ break;
+ case 4:
+ w3(0x68); (void)r1(); w2(0x24);
+ for (i = 0; i < count / 4; i++)
+ ((u32 *)buf)[i] = r4l();
+ w2(4);
+ break;
+ }
+}
+
+/* NB: Watch out for the byte swapped writes ! */
+static void comm_write_block(struct pi_adapter *pi, char *buf, int count)
+{
+ int k;
+
+ switch (pi->mode) {
+ case 0:
+ case 1:
+ w0(0x68); P1;
+ for (k = 0; k < count; k++) {
+ w2(5); w0(buf[k^1]); w2(7);
+ }
+ w2(5); w2(4);
+ break;
+ case 2:
+ w3(0x48); (void)r1();
+ for (k = 0; k < count; k++)
+ w4(buf[k^1]);
+ break;
+ case 3:
+ w3(0x48); (void)r1();
+ for (k = 0; k < count / 2; k++)
+ w4w(pi_swab16(buf, k));
+ break;
+ case 4:
+ w3(0x48); (void)r1();
+ for (k = 0; k < count / 4; k++)
+ w4l(pi_swab32(buf, k));
+ break;
+ }
+}
+
+static void comm_log_adapter(struct pi_adapter *pi, char *scratch, int verbose)
+{
+ static char * const mode_string[] = {
+ "4-bit", "8-bit", "EPP-8", "EPP-16", "EPP-32" };
+
+ dev_info(&pi->dev, "comm, DataStor Commuter at 0x%x, mode %d (%s), delay %d\n",
+ pi->port, pi->mode, mode_string[pi->mode], pi->delay);
+}
+
+static struct pi_protocol comm = {
+ .owner = THIS_MODULE,
+ .name = "comm",
+ .max_mode = 5,
+ .epp_first = 2,
+ .default_delay = 1,
+ .max_units = 1,
+ .write_regr = comm_write_regr,
+ .read_regr = comm_read_regr,
+ .write_block = comm_write_block,
+ .read_block = comm_read_block,
+ .connect = comm_connect,
+ .disconnect = comm_disconnect,
+ .log_adapter = comm_log_adapter,
+ .sht = { PATA_PARPORT_SHT("pata_parport-comm") },
+};
+
+MODULE_LICENSE("GPL");
+module_pata_parport_driver(comm);
--
Ondrej Zary