2022-03-11 03:51:01

by Ondrej Zary

[permalink] [raw]
Subject: [PATCH v0] pata_parport: add driver (PARIDE replacement)

Add pata_parport (PARIDE replacement) core libata driver.

The original paride protocol modules are used for now so allow them to
be compiled without old PARIDE core.

Signed-off-by: Ondrej Zary <[email protected]>
---
drivers/Makefile | 2 +-
drivers/ata/Kconfig | 22 +
drivers/ata/Makefile | 2 +
drivers/ata/parport/Makefile | 3 +
drivers/ata/parport/pata_parport.c | 805 +++++++++++++++++++++++++++++
drivers/ata/parport/pata_parport.h | 108 ++++
drivers/block/paride/Kconfig | 32 +-
drivers/block/paride/paride.h | 5 +
8 files changed, 962 insertions(+), 17 deletions(-)
create mode 100644 drivers/ata/parport/Makefile
create mode 100644 drivers/ata/parport/pata_parport.c
create mode 100644 drivers/ata/parport/pata_parport.h

diff --git a/drivers/Makefile b/drivers/Makefile
index a110338c860c..8ec515f3614e 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -98,7 +98,7 @@ obj-$(CONFIG_DIO) += dio/
obj-$(CONFIG_SBUS) += sbus/
obj-$(CONFIG_ZORRO) += zorro/
obj-$(CONFIG_ATA_OVER_ETH) += block/aoe/
-obj-$(CONFIG_PARIDE) += block/paride/
+obj-y += block/paride/
obj-$(CONFIG_TC) += tc/
obj-$(CONFIG_USB_PHY) += usb/
obj-$(CONFIG_USB) += usb/
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index e5641e6c52ee..671c27b77a48 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -1161,6 +1161,28 @@ config PATA_WINBOND_VLB
Support for the Winbond W83759A controller on Vesa Local Bus
systems.

+config PATA_PARPORT
+ tristate "Parallel port IDE device support"
+ depends on PARPORT_PC && PARIDE=n
+ help
+ There are many external CD-ROM and disk devices that connect through
+ your computer's parallel port. Most of them are actually IDE devices
+ using a parallel port IDE adapter. This option enables the
+ PATA_PARPORT subsystem which contains drivers for many of these
+ external drives.
+ Read <file:Documentation/admin-guide/blockdev/paride.rst> for more
+ information.
+
+ If your parallel port support is in a loadable module, you must build
+ PATA_PARPORT as a module. If you built PATA_PARPORT support into your
+ kernel, you may still build the individual protocol modules
+ as loadable modules. Use the old PARIDE protocol modules.
+ If you build this support as a module, it will be called pata_parport.
+
+ Unlike the old PARIDE, there are no high-level drivers needed.
+ The IDE devices behind parallel port adapters are handled by the
+ ATA layer.
+
comment "Generic fallback / legacy drivers"

config PATA_ACPI
diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
index b8aebfb14e82..171045578541 100644
--- a/drivers/ata/Makefile
+++ b/drivers/ata/Makefile
@@ -114,6 +114,8 @@ obj-$(CONFIG_PATA_SAMSUNG_CF) += pata_samsung_cf.o

obj-$(CONFIG_PATA_PXA) += pata_pxa.o

+obj-$(CONFIG_PATA_PARPORT) += parport/
+
# Should be last but two libata driver
obj-$(CONFIG_PATA_ACPI) += pata_acpi.o
# Should be last but one libata driver
diff --git a/drivers/ata/parport/Makefile b/drivers/ata/parport/Makefile
new file mode 100644
index 000000000000..3ec4a4a66e26
--- /dev/null
+++ b/drivers/ata/parport/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0
+
+obj-$(CONFIG_PATA_PARPORT) += pata_parport.o
diff --git a/drivers/ata/parport/pata_parport.c b/drivers/ata/parport/pata_parport.c
new file mode 100644
index 000000000000..3ea8d824091e
--- /dev/null
+++ b/drivers/ata/parport/pata_parport.c
@@ -0,0 +1,805 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/parport.h>
+#include "pata_parport.h"
+
+#define DRV_NAME "pata_parport"
+
+static DEFINE_IDR(parport_list);
+static DEFINE_IDR(protocols);
+static DEFINE_IDA(pata_parport_bus_dev_ids);
+static DEFINE_MUTEX(pi_mutex);
+
+static bool probe = true;
+module_param(probe, bool, 0644);
+MODULE_PARM_DESC(probe, "Enable automatic device probing (0=off, 1=on [default])");
+
+static bool verbose;
+module_param(verbose, bool, 0644);
+MODULE_PARM_DESC(verbose, "Enable verbose messages (0=off [default], 1=on)");
+
+#define DISCONNECT_TIMEOUT (HZ / 10)
+
+static void pi_connect(struct pi_adapter *pi)
+{
+ del_timer_sync(&pi->timer);
+ if (!pi->claimed) {
+ pi->claimed = true;
+ parport_claim_or_block(pi->pardev);
+ pi->proto->connect(pi);
+ }
+}
+
+static void pi_disconnect_timer(struct timer_list *t)
+{
+ struct pi_adapter *pi = from_timer(pi, t, timer);
+
+ if (pi->claimed) {
+ pi->proto->disconnect(pi);
+ parport_release(pi->pardev);
+ pi->claimed = false;
+ }
+}
+
+/* functions taken from libata-sff.c and converted from direct port I/O */
+static void pata_parport_dev_select(struct ata_port *ap, unsigned int device)
+{
+ struct pi_adapter *pi = ap->host->private_data;
+ u8 tmp;
+
+ if (device == 0)
+ tmp = ATA_DEVICE_OBS;
+ else
+ tmp = ATA_DEVICE_OBS | ATA_DEV1;
+
+ pi_connect(pi);
+ pi->proto->write_regr(pi, 0, ATA_REG_DEVICE, tmp);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+ ata_sff_pause(ap);
+}
+
+static bool pata_parport_devchk(struct ata_port *ap, unsigned int device)
+{
+ struct pi_adapter *pi = ap->host->private_data;
+ u8 nsect, lbal;
+
+ pata_parport_dev_select(ap, device);
+
+ pi_connect(pi);
+ pi->proto->write_regr(pi, 0, ATA_REG_NSECT, 0x55);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAL, 0xaa);
+
+ pi->proto->write_regr(pi, 0, ATA_REG_NSECT, 0xaa);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAL, 0x55);
+
+ pi->proto->write_regr(pi, 0, ATA_REG_NSECT, 055);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAL, 0xaa);
+
+ nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
+ lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+
+ if ((nsect == 0x55) && (lbal == 0xaa))
+ return true; /* we found a device */
+
+ return false; /* nothing found */
+}
+
+static int pata_parport_bus_softreset(struct ata_port *ap, unsigned int devmask,
+ unsigned long deadline)
+{
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ /* software reset. causes dev0 to be selected */
+ pi->proto->write_regr(pi, 1, 6, ap->ctl);
+ udelay(20);
+ pi->proto->write_regr(pi, 1, 6, ap->ctl | ATA_SRST);
+ udelay(20);
+ pi->proto->write_regr(pi, 1, 6, ap->ctl);
+ ap->last_ctl = ap->ctl;
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+
+ /* wait the port to become ready */
+ return ata_sff_wait_after_reset(&ap->link, devmask, deadline);
+}
+
+static int pata_parport_softreset(struct ata_link *link, unsigned int *classes,
+ unsigned long deadline)
+{
+ struct ata_port *ap = link->ap;
+ unsigned int devmask = 0;
+ int rc;
+ u8 err;
+
+ /* determine if device 0/1 are present */
+ if (pata_parport_devchk(ap, 0))
+ devmask |= (1 << 0);
+ if (pata_parport_devchk(ap, 1))
+ devmask |= (1 << 1);
+
+ /* select device 0 again */
+ pata_parport_dev_select(ap, 0);
+
+ /* issue bus reset */
+ rc = pata_parport_bus_softreset(ap, devmask, deadline);
+ if (rc && rc != -ENODEV) {
+ ata_link_err(link, "SRST failed (errno=%d)\n", rc);
+ return rc;
+ }
+
+ /* determine by signature whether we have ATA or ATAPI devices */
+ classes[0] = ata_sff_dev_classify(&link->device[0],
+ devmask & (1 << 0), &err);
+ if (err != 0x81)
+ classes[1] = ata_sff_dev_classify(&link->device[1],
+ devmask & (1 << 1), &err);
+
+ return 0;
+}
+
+static u8 pata_parport_check_status(struct ata_port *ap)
+{
+ u8 status;
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ status = pi->proto->read_regr(pi, 0, ATA_REG_STATUS);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+
+ return status;
+}
+
+static u8 pata_parport_check_altstatus(struct ata_port *ap)
+{
+ u8 altstatus;
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ altstatus = pi->proto->read_regr(pi, 1, 6);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+
+ return altstatus;
+}
+
+static void pata_parport_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
+{
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ if (tf->ctl != ap->last_ctl) {
+ pi->proto->write_regr(pi, 1, 6, tf->ctl);
+ ap->last_ctl = tf->ctl;
+ ata_wait_idle(ap);
+ }
+
+ if (tf->flags & ATA_TFLAG_ISADDR) {
+ if (tf->flags & ATA_TFLAG_LBA48) {
+ pi->proto->write_regr(pi, 0, ATA_REG_FEATURE, tf->hob_feature);
+ pi->proto->write_regr(pi, 0, ATA_REG_NSECT, tf->hob_nsect);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAL, tf->hob_lbal);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAM, tf->hob_lbam);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAH, tf->hob_lbah);
+ }
+ pi->proto->write_regr(pi, 0, ATA_REG_FEATURE, tf->feature);
+ pi->proto->write_regr(pi, 0, ATA_REG_NSECT, tf->nsect);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAL, tf->lbal);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAM, tf->lbam);
+ pi->proto->write_regr(pi, 0, ATA_REG_LBAH, tf->lbah);
+ }
+
+ if (tf->flags & ATA_TFLAG_DEVICE)
+ pi->proto->write_regr(pi, 0, ATA_REG_DEVICE, tf->device);
+
+ ata_wait_idle(ap);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+}
+
+static void pata_parport_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
+{
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ tf->status = pi->proto->read_regr(pi, 0, ATA_REG_STATUS);
+ tf->error = pi->proto->read_regr(pi, 0, ATA_REG_ERR);
+ tf->nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
+ tf->lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
+ tf->lbam = pi->proto->read_regr(pi, 0, ATA_REG_LBAM);
+ tf->lbah = pi->proto->read_regr(pi, 0, ATA_REG_LBAH);
+ tf->device = pi->proto->read_regr(pi, 0, ATA_REG_DEVICE);
+
+ if (tf->flags & ATA_TFLAG_LBA48) {
+ pi->proto->write_regr(pi, 1, 6, tf->ctl | ATA_HOB);
+ tf->hob_feature = pi->proto->read_regr(pi, 0, ATA_REG_ERR);
+ tf->hob_nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
+ tf->hob_lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
+ tf->hob_lbam = pi->proto->read_regr(pi, 0, ATA_REG_LBAM);
+ tf->hob_lbah = pi->proto->read_regr(pi, 0, ATA_REG_LBAH);
+ pi->proto->write_regr(pi, 1, 6, tf->ctl);
+ ap->last_ctl = tf->ctl;
+ }
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+}
+
+static void pata_parport_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)
+{
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ pi->proto->write_regr(pi, 0, ATA_REG_CMD, tf->command);
+ ata_sff_pause(ap);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+}
+
+static unsigned int pata_parport_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf,
+ unsigned int buflen, int rw)
+{
+ struct ata_port *ap = qc->dev->link->ap;
+ struct pi_adapter *pi = ap->host->private_data;
+
+ pi_connect(pi);
+ if (rw == READ)
+ pi->proto->read_block(pi, buf, buflen);
+ else
+ pi->proto->write_block(pi, buf, buflen);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+
+ return buflen;
+}
+
+static void pata_parport_drain_fifo(struct ata_queued_cmd *qc)
+{
+ int count;
+ struct ata_port *ap;
+ struct pi_adapter *pi;
+ char junk[2];
+
+ /* We only need to flush incoming data when a command was running */
+ if (qc == NULL || qc->dma_dir == DMA_TO_DEVICE)
+ return;
+
+ ap = qc->ap;
+ pi = ap->host->private_data;
+ /* Drain up to 64K of data before we give up this recovery method */
+ for (count = 0; (pata_parport_check_status(ap) & ATA_DRQ)
+ && count < 65536; count += 2) {
+ pi_connect(pi);
+ pi->proto->read_block(pi, junk, 2);
+ mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
+ }
+
+ if (count)
+ ata_port_dbg(ap, "drained %d bytes to clear DRQ\n", count);
+}
+
+static void pata_parport_lost_interrupt(struct ata_port *ap)
+{
+ u8 status;
+ struct ata_queued_cmd *qc;
+
+ /* Only one outstanding command per SFF channel */
+ qc = ata_qc_from_tag(ap, ap->link.active_tag);
+ /* We cannot lose an interrupt on a non-existent or polled command */
+ if (!qc || qc->tf.flags & ATA_TFLAG_POLLING)
+ return;
+ /*
+ * See if the controller thinks it is still busy - if so the command
+ * isn't a lost IRQ but is still in progress
+ */
+ status = pata_parport_check_altstatus(ap);
+ if (status & ATA_BUSY)
+ return;
+
+ /*
+ * There was a command running, we are no longer busy and we have
+ * no interrupt.
+ */
+ ata_port_warn(ap, "lost interrupt (Status 0x%x)\n", status);
+ /* Run the host interrupt logic as if the interrupt had not been lost */
+ ata_sff_port_intr(ap, qc);
+}
+
+static struct ata_port_operations pata_parport_port_ops = {
+ .inherits = &ata_sff_port_ops,
+
+ .softreset = pata_parport_softreset,
+ .hardreset = NULL,
+
+ .sff_dev_select = pata_parport_dev_select,
+ .sff_check_status = pata_parport_check_status,
+ .sff_check_altstatus = pata_parport_check_altstatus,
+ .sff_tf_load = pata_parport_tf_load,
+ .sff_tf_read = pata_parport_tf_read,
+ .sff_exec_command = pata_parport_exec_command,
+ .sff_data_xfer = pata_parport_data_xfer,
+ .sff_drain_fifo = pata_parport_drain_fifo,
+
+ .lost_interrupt = pata_parport_lost_interrupt,
+};
+
+static const struct ata_port_info pata_parport_port_info = {
+ .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_POLLING,
+ .pio_mask = ATA_PIO0,
+ /* No DMA */
+ .port_ops = &pata_parport_port_ops,
+};
+
+static void pi_release(struct pi_adapter *pi)
+{
+ parport_unregister_device(pi->pardev);
+ if (pi->proto->release_proto)
+ pi->proto->release_proto(pi);
+ module_put(pi->proto->owner);
+}
+
+static int default_test_proto(struct pi_adapter *pi, char *scratch)
+{
+ int j, k;
+ int e[2] = { 0, 0 };
+
+ pi->proto->connect(pi);
+
+ for (j = 0; j < 2; j++) {
+ pi->proto->write_regr(pi, 0, 6, 0xa0 + j * 0x10);
+ for (k = 0; k < 256; k++) {
+ pi->proto->write_regr(pi, 0, 2, k ^ 0xaa);
+ pi->proto->write_regr(pi, 0, 3, k ^ 0x55);
+ if (pi->proto->read_regr(pi, 0, 2) != (k ^ 0xaa))
+ e[j]++;
+ }
+ }
+ pi->proto->disconnect(pi);
+
+ if (verbose)
+ dev_info(&pi->dev, "%s: port 0x%x, mode %d, test=(%d,%d)\n",
+ pi->proto->name, pi->port,
+ pi->mode, e[0], e[1]);
+
+ return e[0] && e[1]; /* not here if both > 0 */
+}
+
+static int pi_test_proto(struct pi_adapter *pi, char *scratch)
+{
+ int res;
+
+ parport_claim_or_block(pi->pardev);
+ if (pi->proto->test_proto)
+ res = pi->proto->test_proto(pi, scratch, verbose);
+ else
+ res = default_test_proto(pi, scratch);
+ parport_release(pi->pardev);
+
+ return res;
+}
+
+static bool pi_probe_mode(struct pi_adapter *pi, int max, char *scratch)
+{
+ int best, range;
+
+ if (pi->mode != -1) {
+ if (pi->mode >= max)
+ return false;
+ range = 3;
+ if (pi->mode >= pi->proto->epp_first)
+ range = 8;
+ if (range == 8 && pi->port % 8)
+ return false;
+ return !pi_test_proto(pi, scratch);
+ }
+ best = -1;
+ for (pi->mode = 0; pi->mode < max; pi->mode++) {
+ range = 3;
+ if (pi->mode >= pi->proto->epp_first)
+ range = 8;
+ if (range == 8 && pi->port % 8)
+ break;
+ if (!pi_test_proto(pi, scratch))
+ best = pi->mode;
+ }
+ pi->mode = best;
+ return best > -1;
+}
+
+static bool pi_probe_unit(struct pi_adapter *pi, int unit, char *scratch)
+{
+ int max, s, e;
+
+ s = unit;
+ e = s + 1;
+
+ if (s == -1) {
+ s = 0;
+ e = pi->proto->max_units;
+ }
+
+ if (pi->proto->test_port) {
+ parport_claim_or_block(pi->pardev);
+ max = pi->proto->test_port(pi);
+ parport_release(pi->pardev);
+ } else {
+ max = pi->proto->max_mode;
+ }
+
+ if (pi->proto->probe_unit) {
+ parport_claim_or_block(pi->pardev);
+ for (pi->unit = s; pi->unit < e; pi->unit++) {
+ if (pi->proto->probe_unit(pi)) {
+ parport_release(pi->pardev);
+ return pi_probe_mode(pi, max, scratch);
+ }
+ }
+ parport_release(pi->pardev);
+ return false;
+ }
+
+ return pi_probe_mode(pi, max, scratch);
+}
+
+static void pata_parport_dev_release(struct device *dev)
+{
+ struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev);
+
+ kfree(pi);
+}
+
+static void pata_parport_bus_release(struct device *dev)
+{
+ /* nothing to do here but required to avoid warning on device removal */
+}
+
+static struct bus_type pata_parport_bus_type = {
+ .name = DRV_NAME,
+};
+
+static struct device pata_parport_bus = {
+ .init_name = DRV_NAME,
+ .release = pata_parport_bus_release,
+};
+
+/* temporary for old paride protocol modules */
+static struct scsi_host_template pata_parport_sht = {
+ PATA_PARPORT_SHT("pata_parport")
+};
+
+static struct pi_adapter *pi_init_one(struct parport *parport,
+ struct pi_protocol *pr, int mode, int unit, int delay)
+{
+ struct pardev_cb par_cb = { };
+ char scratch[512];
+ const struct ata_port_info *ppi[] = { &pata_parport_port_info };
+ struct ata_host *host;
+ struct pi_adapter *pi;
+
+ pi = kzalloc(sizeof(struct pi_adapter), GFP_KERNEL);
+ if (!pi)
+ return NULL;
+
+ /* set up pi->dev before pi_probe_unit() so it can use dev_printk() */
+ pi->dev.parent = &pata_parport_bus;
+ pi->dev.bus = &pata_parport_bus_type;
+ pi->dev.driver = &pr->driver;
+ pi->dev.release = pata_parport_dev_release;
+ pi->dev.id = ida_alloc(&pata_parport_bus_dev_ids, GFP_KERNEL);
+ if (pi->dev.id < 0)
+ return NULL; /* pata_parport_dev_release will do kfree(pi) */
+ dev_set_name(&pi->dev, "pata_parport.%u", pi->dev.id);
+ if (device_register(&pi->dev)) {
+ put_device(&pi->dev);
+ goto out_ida_free;
+ }
+
+ pi->proto = pr;
+
+ if (!try_module_get(pi->proto->owner))
+ goto out_unreg_dev;
+ if (pi->proto->init_proto && pi->proto->init_proto(pi) < 0)
+ goto out_module_put;
+
+ pi->delay = (delay == -1) ? pi->proto->default_delay : delay;
+ pi->mode = mode;
+ pi->port = parport->base;
+
+ par_cb.private = pi;
+ pi->pardev = parport_register_dev_model(parport, dev_name(&pi->dev),
+ &par_cb, pi->dev.id);
+ if (!pi->pardev)
+ goto out_module_put;
+
+ if (!pi_probe_unit(pi, unit, scratch)) {
+ dev_info(&pi->dev, "Adapter not found\n");
+ goto out_unreg_parport;
+ }
+
+ pi->proto->log_adapter(pi, scratch, verbose);
+
+ host = ata_host_alloc_pinfo(&pi->dev, ppi, 1);
+ if (!host)
+ goto out_unreg_parport;
+ dev_set_drvdata(&pi->dev, host);
+ host->private_data = pi;
+
+ ata_port_desc(host->ports[0], "port %s", pi->pardev->port->name);
+ ata_port_desc(host->ports[0], "protocol %s", pi->proto->name);
+
+ timer_setup(&pi->timer, pi_disconnect_timer, 0);
+
+ if (ata_host_activate(host, 0, NULL, 0, &pata_parport_sht))
+ goto out_unreg_parport;
+
+ return pi;
+
+out_unreg_parport:
+ parport_unregister_device(pi->pardev);
+ if (pi->proto->release_proto)
+ pi->proto->release_proto(pi);
+out_module_put:
+ module_put(pi->proto->owner);
+out_unreg_dev:
+ device_unregister(&pi->dev);
+out_ida_free:
+ ida_free(&pata_parport_bus_dev_ids, pi->dev.id);
+ return NULL;
+}
+
+int pata_parport_register_driver(struct pi_protocol *pr)
+{
+ int error;
+ struct parport *parport;
+ int port_num;
+
+ pr->driver.bus = &pata_parport_bus_type;
+ pr->driver.name = pr->name;
+ error = driver_register(&pr->driver);
+ if (error)
+ return error;
+
+ mutex_lock(&pi_mutex);
+ error = idr_alloc(&protocols, pr, 0, 0, GFP_KERNEL);
+ if (error < 0) {
+ driver_unregister(&pr->driver);
+ mutex_unlock(&pi_mutex);
+ return error;
+ }
+
+ pr_info("pata_parport: protocol %s registered\n", pr->name);
+
+ if (probe) {
+ /* probe all parports using this protocol */
+ idr_for_each_entry(&parport_list, parport, port_num)
+ pi_init_one(parport, pr, -1, 0, -1);
+ }
+ mutex_unlock(&pi_mutex);
+
+ return 0;
+}
+EXPORT_SYMBOL(pata_parport_register_driver);
+
+void pata_parport_unregister_driver(struct pi_protocol *pr)
+{
+ struct pi_protocol *pr_iter;
+ int id = -1;
+
+ mutex_lock(&pi_mutex);
+ idr_for_each_entry(&protocols, pr_iter, id) {
+ if (pr_iter == pr)
+ break;
+ }
+ idr_remove(&protocols, id);
+ mutex_unlock(&pi_mutex);
+ driver_unregister(&pr->driver);
+}
+EXPORT_SYMBOL(pata_parport_unregister_driver);
+
+static ssize_t new_device_store(struct bus_type *bus, const char *buf, size_t count)
+{
+ char port[12] = "auto";
+ char protocol[8] = "auto";
+ int mode = -1, unit = -1, delay = -1;
+ struct pi_protocol *pr, *pr_wanted;
+ struct device_driver *drv;
+ struct parport *parport;
+ int port_num, port_wanted, pr_num;
+ bool ok = false;
+
+ if (sscanf(buf, "%11s %7s %d %d %d",
+ port, protocol, &mode, &unit, &delay) < 1)
+ return -EINVAL;
+
+ if (sscanf(port, "parport%u", &port_wanted) < 1) {
+ if (!strcmp(port, "auto")) {
+ port_wanted = -1;
+ } else {
+ pr_err("invalid port name %s\n", port);
+ return -EINVAL;
+ }
+ }
+
+ drv = driver_find(protocol, &pata_parport_bus_type);
+ if (!drv) {
+ if (!strcmp(protocol, "auto")) {
+ pr_wanted = NULL;
+ } else {
+ pr_err("protocol %s not found\n", protocol);
+ return -EINVAL;
+ }
+ } else {
+ pr_wanted = container_of(drv, struct pi_protocol, driver);
+ }
+
+ mutex_lock(&pi_mutex);
+ /* walk all parports */
+ idr_for_each_entry(&parport_list, parport, port_num) {
+ if (port_num == port_wanted || port_wanted == -1) {
+ parport = parport_find_number(port_num);
+ if (!parport) {
+ pr_err("no such port %s\n", port);
+ mutex_unlock(&pi_mutex);
+ return -ENODEV;
+ }
+ /* walk all protocols */
+ idr_for_each_entry(&protocols, pr, pr_num) {
+ if (pr == pr_wanted || !pr_wanted)
+ if (pi_init_one(parport, pr, mode, unit,
+ delay))
+ ok = true;
+ }
+ parport_put_port(parport);
+ }
+ }
+ mutex_unlock(&pi_mutex);
+ if (!ok)
+ return -ENODEV;
+
+ return count;
+}
+static BUS_ATTR_WO(new_device);
+
+static void pi_remove_one(struct device *dev)
+{
+ struct ata_host *host = dev_get_drvdata(dev);
+ struct pi_adapter *pi = host->private_data;
+
+ ata_host_detach(host);
+ del_timer_sync(&pi->timer);
+ if (pi->claimed) {
+ pi->proto->disconnect(pi);
+ parport_release(pi->pardev);
+ }
+ pi_release(pi);
+ device_unregister(dev);
+ ida_free(&pata_parport_bus_dev_ids, dev->id);
+ /* pata_parport_dev_release will do kfree(pi) */
+}
+
+static ssize_t delete_device_store(struct bus_type *bus, const char *buf, size_t count)
+{
+ struct device *dev;
+ char device_name[32];
+
+ if (sscanf(buf, "%31s", device_name) < 1)
+ return -EINVAL;
+
+ mutex_lock(&pi_mutex);
+ dev = bus_find_device_by_name(bus, NULL, device_name);
+ if (!dev) {
+ mutex_unlock(&pi_mutex);
+ return -ENODEV;
+ }
+
+ pi_remove_one(dev);
+ mutex_unlock(&pi_mutex);
+
+ return count;
+}
+static BUS_ATTR_WO(delete_device);
+
+static void pata_parport_attach(struct parport *port)
+{
+ struct pi_protocol *pr;
+ int pr_num, id;
+
+ mutex_lock(&pi_mutex);
+ id = idr_alloc(&parport_list, port, port->number, port->number, GFP_KERNEL);
+ if (id < 0) {
+ mutex_unlock(&pi_mutex);
+ return;
+ }
+
+ if (probe) {
+ /* probe this port using all protocols */
+ idr_for_each_entry(&protocols, pr, pr_num)
+ pi_init_one(port, pr, -1, 0, -1);
+ }
+ mutex_unlock(&pi_mutex);
+}
+
+static int pi_remove_port(struct device *dev, void *p)
+{
+ struct ata_host *host = dev_get_drvdata(dev);
+ struct pi_adapter *pi = host->private_data;
+
+ if (pi->pardev->port == p)
+ pi_remove_one(dev);
+
+ return 0;
+}
+
+static void pata_parport_detach(struct parport *port)
+{
+ mutex_lock(&pi_mutex);
+ bus_for_each_dev(&pata_parport_bus_type, NULL, port, pi_remove_port);
+ idr_remove(&parport_list, port->number);
+ mutex_unlock(&pi_mutex);
+}
+
+static struct parport_driver pata_parport_driver = {
+ .name = DRV_NAME,
+ .match_port = pata_parport_attach,
+ .detach = pata_parport_detach,
+ .devmodel = true,
+};
+
+static __init int pata_parport_init(void)
+{
+ int error;
+
+ error = bus_register(&pata_parport_bus_type);
+ if (error) {
+ pr_err("failed to register pata_parport bus, error: %d\n", error);
+ return error;
+ }
+
+ error = device_register(&pata_parport_bus);
+ if (error) {
+ pr_err("failed to register pata_parport bus, error: %d\n", error);
+ goto out_unregister_bus;
+ }
+
+ error = bus_create_file(&pata_parport_bus_type, &bus_attr_new_device);
+ if (error) {
+ pr_err("unable to create sysfs file, error: %d\n", error);
+ goto out_unregister_dev;
+ }
+
+ error = bus_create_file(&pata_parport_bus_type, &bus_attr_delete_device);
+ if (error) {
+ pr_err("unable to create sysfs file, error: %d\n", error);
+ goto out_remove_new;
+ }
+
+ error = parport_register_driver(&pata_parport_driver);
+ if (error) {
+ pr_err("unable to register parport driver, error: %d\n", error);
+ goto out_remove_del;
+ }
+
+ return 0;
+
+out_remove_del:
+ bus_remove_file(&pata_parport_bus_type, &bus_attr_delete_device);
+out_remove_new:
+ bus_remove_file(&pata_parport_bus_type, &bus_attr_new_device);
+out_unregister_dev:
+ device_unregister(&pata_parport_bus);
+out_unregister_bus:
+ bus_unregister(&pata_parport_bus_type);
+ return error;
+}
+
+static __exit void pata_parport_exit(void)
+{
+ parport_unregister_driver(&pata_parport_driver);
+ bus_remove_file(&pata_parport_bus_type, &bus_attr_new_device);
+ bus_remove_file(&pata_parport_bus_type, &bus_attr_delete_device);
+ device_unregister(&pata_parport_bus);
+ bus_unregister(&pata_parport_bus_type);
+}
+
+MODULE_AUTHOR("Ondrej Zary");
+MODULE_DESCRIPTION("driver for parallel port ATA adapters");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("paride");
+
+module_init(pata_parport_init);
+module_exit(pata_parport_exit);
diff --git a/drivers/ata/parport/pata_parport.h b/drivers/ata/parport/pata_parport.h
new file mode 100644
index 000000000000..d8d45f8bc742
--- /dev/null
+++ b/drivers/ata/parport/pata_parport.h
@@ -0,0 +1,108 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * pata_parport.h (c) 1997-8 Grant R. Guenther <[email protected]>
+ * Under the terms of the GPL.
+ *
+ * This file defines the interface for parallell port IDE adapter chip drivers.
+ */
+
+#include <linux/libata.h>
+
+#define PI_PCD 1 /* dummy for paride protocol modules */
+
+struct pi_adapter {
+ struct device dev;
+ struct pi_protocol *proto; /* adapter protocol */
+ int port; /* base address of parallel port */
+ int mode; /* transfer mode in use */
+ int delay; /* adapter delay setting */
+ int devtype; /* dummy for paride protocol modules */
+ char *device; /* dummy for paride protocol modules */
+ int unit; /* unit number for chained adapters */
+ int saved_r0; /* saved port state */
+ int saved_r2; /* saved port state */
+ unsigned long private; /* for protocol module */
+ struct pardevice *pardev; /* pointer to pardevice */
+ bool claimed; /* parport has already been claimed */
+ struct timer_list timer; /* disconnect timer */
+};
+
+typedef struct pi_adapter PIA; /* for paride protocol modules */
+
+/* registers are addressed as (cont,regr)
+ * cont: 0 for command register file, 1 for control register(s)
+ * regr: 0-7 for register number.
+ */
+
+/* macros and functions exported to the protocol modules */
+#define delay_p (pi->delay ? udelay(pi->delay) : (void)0)
+#define out_p(offs, byte) do { outb(byte, pi->port + offs); delay_p; } while (0)
+#define in_p(offs) (delay_p, inb(pi->port + offs))
+
+#define w0(byte) out_p(0, byte)
+#define r0() (in_p(0) & 0xff)
+#define w1(byte) out_p(1, byte)
+#define r1() (in_p(1) & 0xff)
+#define w2(byte) out_p(2, byte)
+#define r2() (in_p(2) & 0xff)
+#define w3(byte) out_p(3, byte)
+#define w4(byte) out_p(4, byte)
+#define r4() (in_p(4) & 0xff)
+#define w4w(data) do { outw(data, pi->port + 4); delay_p; } while (0)
+#define w4l(data) do { outl(data, pi->port + 4); delay_p; } while (0)
+#define r4w() (delay_p, inw(pi->port + 4) & 0xffff)
+#define r4l() (delay_p, inl(pi->port + 4) & 0xffffffff)
+
+static inline u16 pi_swab16(char *b, int k)
+{
+ union { u16 u; char t[2]; } r;
+
+ r.t[0] = b[2 * k + 1]; r.t[1] = b[2 * k];
+ return r.u;
+}
+
+static inline u32 pi_swab32(char *b, int k)
+{
+ union { u32 u; char f[4]; } r;
+
+ r.f[0] = b[4 * k + 1]; r.f[1] = b[4 * k];
+ r.f[2] = b[4 * k + 3]; r.f[3] = b[4 * k + 2];
+ return r.u;
+}
+
+struct pi_protocol {
+ char name[8];
+
+ int max_mode;
+ int epp_first; /* modes >= this use 8 ports */
+
+ int default_delay;
+ int max_units; /* max chained units probed for */
+
+ void (*write_regr)(struct pi_adapter *pi, int cont, int regr, int val);
+ int (*read_regr)(struct pi_adapter *pi, int cont, int regr);
+ void (*write_block)(struct pi_adapter *pi, char *buf, int count);
+ void (*read_block)(struct pi_adapter *pi, char *buf, int count);
+
+ void (*connect)(struct pi_adapter *pi);
+ void (*disconnect)(struct pi_adapter *pi);
+
+ int (*test_port)(struct pi_adapter *pi);
+ int (*probe_unit)(struct pi_adapter *pi);
+ int (*test_proto)(struct pi_adapter *pi, char *scratch, int verbose);
+ void (*log_adapter)(struct pi_adapter *pi, char *scratch, int verbose);
+
+ int (*init_proto)(struct pi_adapter *pi);
+ void (*release_proto)(struct pi_adapter *pi);
+ struct module *owner;
+ struct device_driver driver;
+ struct scsi_host_template sht;
+};
+
+#define PATA_PARPORT_SHT ATA_PIO_SHT
+
+int pata_parport_register_driver(struct pi_protocol *pr);
+void pata_parport_unregister_driver(struct pi_protocol *pr);
+/* defines for old paride protocol modules */
+#define paride_register pata_parport_register_driver
+#define paride_unregister pata_parport_unregister_driver
diff --git a/drivers/block/paride/Kconfig b/drivers/block/paride/Kconfig
index a295634597ba..01e4ef3655c1 100644
--- a/drivers/block/paride/Kconfig
+++ b/drivers/block/paride/Kconfig
@@ -92,11 +92,11 @@ config PARIDE_PG
later fully support this driver.

comment "Parallel IDE protocol modules"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT

config PARIDE_ATEN
tristate "ATEN EH-100 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the ATEN EH-100 parallel port IDE
protocol. This protocol is used in some inexpensive low performance
@@ -109,7 +109,7 @@ config PARIDE_ATEN

config PARIDE_BPCK
tristate "MicroSolutions backpack (Series 5) protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the Micro Solutions BACKPACK
parallel port Series 5 IDE protocol. (Most BACKPACK drives made
@@ -127,7 +127,7 @@ config PARIDE_BPCK

config PARIDE_BPCK6
tristate "MicroSolutions backpack (Series 6) protocol"
- depends on PARIDE && !64BIT
+ depends on (PARIDE || PATA_PARPORT) && !64BIT
help
This option enables support for the Micro Solutions BACKPACK
parallel port Series 6 IDE protocol. (Most BACKPACK drives made
@@ -146,7 +146,7 @@ config PARIDE_BPCK6

config PARIDE_COMM
tristate "DataStor Commuter protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the Commuter parallel port IDE
protocol from DataStor. If you chose to build PARIDE support
@@ -157,7 +157,7 @@ config PARIDE_COMM

config PARIDE_DSTR
tristate "DataStor EP-2000 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the EP-2000 parallel port IDE
protocol from DataStor. If you chose to build PARIDE support
@@ -168,7 +168,7 @@ config PARIDE_DSTR

config PARIDE_FIT2
tristate "FIT TD-2000 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the TD-2000 parallel port IDE
protocol from Fidelity International Technology. This is a simple
@@ -181,7 +181,7 @@ config PARIDE_FIT2

config PARIDE_FIT3
tristate "FIT TD-3000 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the TD-3000 parallel port IDE
protocol from Fidelity International Technology. This protocol is
@@ -194,7 +194,7 @@ config PARIDE_FIT3

config PARIDE_EPAT
tristate "Shuttle EPAT/EPEZ protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the EPAT parallel port IDE protocol.
EPAT is a parallel port IDE adapter manufactured by Shuttle
@@ -216,7 +216,7 @@ config PARIDE_EPATC8

config PARIDE_EPIA
tristate "Shuttle EPIA protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the (obsolete) EPIA parallel port
IDE protocol from Shuttle Technology. This adapter can still be
@@ -228,7 +228,7 @@ config PARIDE_EPIA

config PARIDE_FRIQ
tristate "Freecom IQ ASIC-2 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for version 2 of the Freecom IQ parallel
port IDE adapter. This adapter is used by the Maxell Superdisk
@@ -240,7 +240,7 @@ config PARIDE_FRIQ

config PARIDE_FRPW
tristate "FreeCom power protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the Freecom power parallel port IDE
protocol. If you chose to build PARIDE support into your kernel, you
@@ -251,7 +251,7 @@ config PARIDE_FRPW

config PARIDE_KBIC
tristate "KingByte KBIC-951A/971A protocols"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the KBIC-951A and KBIC-971A parallel
port IDE protocols from KingByte Information Corp. KingByte's
@@ -264,7 +264,7 @@ config PARIDE_KBIC

config PARIDE_KTTI
tristate "KT PHd protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the "PHd" parallel port IDE protocol
from KT Technology. This is a simple (low speed) adapter that is
@@ -277,7 +277,7 @@ config PARIDE_KTTI

config PARIDE_ON20
tristate "OnSpec 90c20 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the (obsolete) 90c20 parallel port
IDE protocol from OnSpec (often marketed under the ValuStore brand
@@ -289,7 +289,7 @@ config PARIDE_ON20

config PARIDE_ON26
tristate "OnSpec 90c26 protocol"
- depends on PARIDE
+ depends on PARIDE || PATA_PARPORT
help
This option enables support for the 90c26 parallel port IDE protocol
from OnSpec Electronics (often marketed under the ValuStore brand
diff --git a/drivers/block/paride/paride.h b/drivers/block/paride/paride.h
index ddb9e589da7f..f3bd01a9c9ec 100644
--- a/drivers/block/paride/paride.h
+++ b/drivers/block/paride/paride.h
@@ -1,3 +1,7 @@
+#if IS_ENABLED(CONFIG_PATA_PARPORT)
+#include "../../ata/parport/pata_parport.h"
+
+#else
#ifndef __DRIVERS_PARIDE_H__
#define __DRIVERS_PARIDE_H__

@@ -170,3 +174,4 @@ void pi_unregister_driver(void *);

#endif /* __DRIVERS_PARIDE_H__ */
/* end of paride.h */
+#endif /* IS_ENABLED(CONFIG_PATA_PARPORT) */
--
Ondrej Zary


2022-03-11 07:54:45

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH v0] pata_parport: add driver (PARIDE replacement)

On Thu, Mar 10, 2022 at 10:28:12PM +0100, Ondrej Zary wrote:
> Add pata_parport (PARIDE replacement) core libata driver.
>
> The original paride protocol modules are used for now so allow them to
> be compiled without old PARIDE core.

I agree with Damien that this needs a bit more text here. Explaining
what kind of hardware this drives, that this will allow to eventually
drop paride, how it reuesed the low-level drivers, etc.

> + If your parallel port support is in a loadable module, you must build
> + PATA_PARPORT as a module. If you built PATA_PARPORT support into your
> + kernel, you may still build the individual protocol modules
> + as loadable modules.

I'd drop the above. The dependencies are already enforced by Kconfig
and we don't really tend to mention this elsewhere.

> + Unlike the old PARIDE, there are no high-level drivers needed.
> + The IDE devices behind parallel port adapters are handled by the
> + ATA layer.

I also don't think this is needed.

> index 000000000000..3ea8d824091e
> --- /dev/null
> +++ b/drivers/ata/parport/pata_parport.c
> @@ -0,0 +1,805 @@
> +// SPDX-License-Identifier: GPL-2.0-only

Please add your copyright statement here.

> +static void pata_parport_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)

Overly long line.

> + pi->proto->write_regr(pi, 0, ATA_REG_NSECT, tf->hob_nsect);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAL, tf->hob_lbal);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAM, tf->hob_lbam);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAH, tf->hob_lbah);

Same here.

> +static void pata_parport_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)

.. and here.

And a bunch more.

> +static void pata_parport_bus_release(struct device *dev)
> +{
> + /* nothing to do here but required to avoid warning on device removal */
> +}
> +
> +static struct bus_type pata_parport_bus_type = {
> + .name = DRV_NAME,
> +};
> +
> +static struct device pata_parport_bus = {
> + .init_name = DRV_NAME,
> + .release = pata_parport_bus_release,
> +};
> +
> +/* temporary for old paride protocol modules */
> +static struct scsi_host_template pata_parport_sht = {
> + PATA_PARPORT_SHT("pata_parport")
> +};

Did you look into my suggestion to use struct pardevice.dev instead?

> index ddb9e589da7f..f3bd01a9c9ec 100644
> --- a/drivers/block/paride/paride.h
> +++ b/drivers/block/paride/paride.h
> @@ -1,3 +1,7 @@
> +#if IS_ENABLED(CONFIG_PATA_PARPORT)
> +#include "../../ata/parport/pata_parport.h"
> +
> +#else

Maybe add a comment here? Also this is a pretty clear indication
that pata_parport.h should be in include/linux/ at least for now.

2022-03-11 21:51:05

by Damien Le Moal

[permalink] [raw]
Subject: Re: [PATCH v0] pata_parport: add driver (PARIDE replacement)

On 3/11/22 06:28, Ondrej Zary wrote:
> Add pata_parport (PARIDE replacement) core libata driver.
>
> The original paride protocol modules are used for now so allow them to
> be compiled without old PARIDE core.
>
> Signed-off-by: Ondrej Zary <[email protected]>
> ---
> drivers/Makefile | 2 +-
> drivers/ata/Kconfig | 22 +
> drivers/ata/Makefile | 2 +
> drivers/ata/parport/Makefile | 3 +
> drivers/ata/parport/pata_parport.c | 805 +++++++++++++++++++++++++++++
> drivers/ata/parport/pata_parport.h | 108 ++++
> drivers/block/paride/Kconfig | 32 +-
> drivers/block/paride/paride.h | 5 +
> 8 files changed, 962 insertions(+), 17 deletions(-)
> create mode 100644 drivers/ata/parport/Makefile
> create mode 100644 drivers/ata/parport/pata_parport.c
> create mode 100644 drivers/ata/parport/pata_parport.h
>
> diff --git a/drivers/Makefile b/drivers/Makefile
> index a110338c860c..8ec515f3614e 100644
> --- a/drivers/Makefile
> +++ b/drivers/Makefile
> @@ -98,7 +98,7 @@ obj-$(CONFIG_DIO) += dio/
> obj-$(CONFIG_SBUS) += sbus/
> obj-$(CONFIG_ZORRO) += zorro/
> obj-$(CONFIG_ATA_OVER_ETH) += block/aoe/
> -obj-$(CONFIG_PARIDE) += block/paride/
> +obj-y += block/paride/
> obj-$(CONFIG_TC) += tc/
> obj-$(CONFIG_USB_PHY) += usb/
> obj-$(CONFIG_USB) += usb/
> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> index e5641e6c52ee..671c27b77a48 100644
> --- a/drivers/ata/Kconfig
> +++ b/drivers/ata/Kconfig
> @@ -1161,6 +1161,28 @@ config PATA_WINBOND_VLB
> Support for the Winbond W83759A controller on Vesa Local Bus
> systems.
>
> +config PATA_PARPORT
> + tristate "Parallel port IDE device support"
> + depends on PARPORT_PC && PARIDE=n

This is very confusing. The change above this one switch paride
compilation to be unconditional, regardless of CONFIG_PARIDE value, but
here, you have the dependency to PARIDE=n. I do not understand... Please
clarify.

The commit message is also way too light given the size of this patch.
Better explanation is needed.

> + help
> + There are many external CD-ROM and disk devices that connect through
> + your computer's parallel port. Most of them are actually IDE devices
> + using a parallel port IDE adapter. This option enables the
> + PATA_PARPORT subsystem which contains drivers for many of these
> + external drives.
> + Read <file:Documentation/admin-guide/blockdev/paride.rst> for more
> + information.
> +
> + If your parallel port support is in a loadable module, you must build
> + PATA_PARPORT as a module. If you built PATA_PARPORT support into your
> + kernel, you may still build the individual protocol modules
> + as loadable modules. Use the old PARIDE protocol modules.
> + If you build this support as a module, it will be called pata_parport.
> +
> + Unlike the old PARIDE, there are no high-level drivers needed.
> + The IDE devices behind parallel port adapters are handled by the
> + ATA layer.
> +
> comment "Generic fallback / legacy drivers"
>
> config PATA_ACPI
> diff --git a/drivers/ata/Makefile b/drivers/ata/Makefile
> index b8aebfb14e82..171045578541 100644
> --- a/drivers/ata/Makefile
> +++ b/drivers/ata/Makefile
> @@ -114,6 +114,8 @@ obj-$(CONFIG_PATA_SAMSUNG_CF) += pata_samsung_cf.o
>
> obj-$(CONFIG_PATA_PXA) += pata_pxa.o
>
> +obj-$(CONFIG_PATA_PARPORT) += parport/
> +
> # Should be last but two libata driver
> obj-$(CONFIG_PATA_ACPI) += pata_acpi.o
> # Should be last but one libata driver
> diff --git a/drivers/ata/parport/Makefile b/drivers/ata/parport/Makefile
> new file mode 100644
> index 000000000000..3ec4a4a66e26
> --- /dev/null
> +++ b/drivers/ata/parport/Makefile
> @@ -0,0 +1,3 @@
> +# SPDX-License-Identifier: GPL-2.0
> +
> +obj-$(CONFIG_PATA_PARPORT) += pata_parport.o
> diff --git a/drivers/ata/parport/pata_parport.c b/drivers/ata/parport/pata_parport.c
> new file mode 100644
> index 000000000000..3ea8d824091e
> --- /dev/null
> +++ b/drivers/ata/parport/pata_parport.c
> @@ -0,0 +1,805 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/parport.h>
> +#include "pata_parport.h"
> +
> +#define DRV_NAME "pata_parport"
> +
> +static DEFINE_IDR(parport_list);
> +static DEFINE_IDR(protocols);
> +static DEFINE_IDA(pata_parport_bus_dev_ids);
> +static DEFINE_MUTEX(pi_mutex);
> +
> +static bool probe = true;
> +module_param(probe, bool, 0644);
> +MODULE_PARM_DESC(probe, "Enable automatic device probing (0=off, 1=on [default])");
> +
> +static bool verbose;
> +module_param(verbose, bool, 0644);
> +MODULE_PARM_DESC(verbose, "Enable verbose messages (0=off [default], 1=on)");
> +
> +#define DISCONNECT_TIMEOUT (HZ / 10)
> +
> +static void pi_connect(struct pi_adapter *pi)
> +{
> + del_timer_sync(&pi->timer);
> + if (!pi->claimed) {
> + pi->claimed = true;
> + parport_claim_or_block(pi->pardev);
> + pi->proto->connect(pi);
> + }
> +}
> +
> +static void pi_disconnect_timer(struct timer_list *t)
> +{
> + struct pi_adapter *pi = from_timer(pi, t, timer);
> +
> + if (pi->claimed) {
> + pi->proto->disconnect(pi);
> + parport_release(pi->pardev);
> + pi->claimed = false;
> + }
> +}
> +
> +/* functions taken from libata-sff.c and converted from direct port I/O */
> +static void pata_parport_dev_select(struct ata_port *ap, unsigned int device)
> +{
> + struct pi_adapter *pi = ap->host->private_data;
> + u8 tmp;
> +
> + if (device == 0)
> + tmp = ATA_DEVICE_OBS;
> + else
> + tmp = ATA_DEVICE_OBS | ATA_DEV1;
> +
> + pi_connect(pi);
> + pi->proto->write_regr(pi, 0, ATA_REG_DEVICE, tmp);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> + ata_sff_pause(ap);
> +}
> +
> +static bool pata_parport_devchk(struct ata_port *ap, unsigned int device)
> +{
> + struct pi_adapter *pi = ap->host->private_data;
> + u8 nsect, lbal;
> +
> + pata_parport_dev_select(ap, device);
> +
> + pi_connect(pi);
> + pi->proto->write_regr(pi, 0, ATA_REG_NSECT, 0x55);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAL, 0xaa);
> +
> + pi->proto->write_regr(pi, 0, ATA_REG_NSECT, 0xaa);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAL, 0x55);
> +
> + pi->proto->write_regr(pi, 0, ATA_REG_NSECT, 055);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAL, 0xaa);
> +
> + nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
> + lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +
> + if ((nsect == 0x55) && (lbal == 0xaa))
> + return true; /* we found a device */
> +
> + return false; /* nothing found */
> +}
> +
> +static int pata_parport_bus_softreset(struct ata_port *ap, unsigned int devmask,
> + unsigned long deadline)
> +{
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + /* software reset. causes dev0 to be selected */
> + pi->proto->write_regr(pi, 1, 6, ap->ctl);
> + udelay(20);
> + pi->proto->write_regr(pi, 1, 6, ap->ctl | ATA_SRST);
> + udelay(20);
> + pi->proto->write_regr(pi, 1, 6, ap->ctl);
> + ap->last_ctl = ap->ctl;
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +
> + /* wait the port to become ready */
> + return ata_sff_wait_after_reset(&ap->link, devmask, deadline);
> +}
> +
> +static int pata_parport_softreset(struct ata_link *link, unsigned int *classes,
> + unsigned long deadline)
> +{
> + struct ata_port *ap = link->ap;
> + unsigned int devmask = 0;
> + int rc;
> + u8 err;
> +
> + /* determine if device 0/1 are present */
> + if (pata_parport_devchk(ap, 0))
> + devmask |= (1 << 0);
> + if (pata_parport_devchk(ap, 1))
> + devmask |= (1 << 1);
> +
> + /* select device 0 again */
> + pata_parport_dev_select(ap, 0);
> +
> + /* issue bus reset */
> + rc = pata_parport_bus_softreset(ap, devmask, deadline);
> + if (rc && rc != -ENODEV) {
> + ata_link_err(link, "SRST failed (errno=%d)\n", rc);
> + return rc;
> + }
> +
> + /* determine by signature whether we have ATA or ATAPI devices */
> + classes[0] = ata_sff_dev_classify(&link->device[0],
> + devmask & (1 << 0), &err);
> + if (err != 0x81)
> + classes[1] = ata_sff_dev_classify(&link->device[1],
> + devmask & (1 << 1), &err);
> +
> + return 0;
> +}
> +
> +static u8 pata_parport_check_status(struct ata_port *ap)
> +{
> + u8 status;
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + status = pi->proto->read_regr(pi, 0, ATA_REG_STATUS);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +
> + return status;
> +}
> +
> +static u8 pata_parport_check_altstatus(struct ata_port *ap)
> +{
> + u8 altstatus;
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + altstatus = pi->proto->read_regr(pi, 1, 6);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +
> + return altstatus;
> +}
> +
> +static void pata_parport_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
> +{
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + if (tf->ctl != ap->last_ctl) {
> + pi->proto->write_regr(pi, 1, 6, tf->ctl);
> + ap->last_ctl = tf->ctl;
> + ata_wait_idle(ap);
> + }
> +
> + if (tf->flags & ATA_TFLAG_ISADDR) {
> + if (tf->flags & ATA_TFLAG_LBA48) {
> + pi->proto->write_regr(pi, 0, ATA_REG_FEATURE, tf->hob_feature);
> + pi->proto->write_regr(pi, 0, ATA_REG_NSECT, tf->hob_nsect);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAL, tf->hob_lbal);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAM, tf->hob_lbam);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAH, tf->hob_lbah);
> + }
> + pi->proto->write_regr(pi, 0, ATA_REG_FEATURE, tf->feature);
> + pi->proto->write_regr(pi, 0, ATA_REG_NSECT, tf->nsect);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAL, tf->lbal);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAM, tf->lbam);
> + pi->proto->write_regr(pi, 0, ATA_REG_LBAH, tf->lbah);
> + }
> +
> + if (tf->flags & ATA_TFLAG_DEVICE)
> + pi->proto->write_regr(pi, 0, ATA_REG_DEVICE, tf->device);
> +
> + ata_wait_idle(ap);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +}
> +
> +static void pata_parport_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
> +{
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + tf->status = pi->proto->read_regr(pi, 0, ATA_REG_STATUS);
> + tf->error = pi->proto->read_regr(pi, 0, ATA_REG_ERR);
> + tf->nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
> + tf->lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
> + tf->lbam = pi->proto->read_regr(pi, 0, ATA_REG_LBAM);
> + tf->lbah = pi->proto->read_regr(pi, 0, ATA_REG_LBAH);
> + tf->device = pi->proto->read_regr(pi, 0, ATA_REG_DEVICE);
> +
> + if (tf->flags & ATA_TFLAG_LBA48) {
> + pi->proto->write_regr(pi, 1, 6, tf->ctl | ATA_HOB);
> + tf->hob_feature = pi->proto->read_regr(pi, 0, ATA_REG_ERR);
> + tf->hob_nsect = pi->proto->read_regr(pi, 0, ATA_REG_NSECT);
> + tf->hob_lbal = pi->proto->read_regr(pi, 0, ATA_REG_LBAL);
> + tf->hob_lbam = pi->proto->read_regr(pi, 0, ATA_REG_LBAM);
> + tf->hob_lbah = pi->proto->read_regr(pi, 0, ATA_REG_LBAH);
> + pi->proto->write_regr(pi, 1, 6, tf->ctl);
> + ap->last_ctl = tf->ctl;
> + }
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +}
> +
> +static void pata_parport_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)
> +{
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + pi->proto->write_regr(pi, 0, ATA_REG_CMD, tf->command);
> + ata_sff_pause(ap);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +}
> +
> +static unsigned int pata_parport_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf,
> + unsigned int buflen, int rw)
> +{
> + struct ata_port *ap = qc->dev->link->ap;
> + struct pi_adapter *pi = ap->host->private_data;
> +
> + pi_connect(pi);
> + if (rw == READ)
> + pi->proto->read_block(pi, buf, buflen);
> + else
> + pi->proto->write_block(pi, buf, buflen);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> +
> + return buflen;
> +}
> +
> +static void pata_parport_drain_fifo(struct ata_queued_cmd *qc)
> +{
> + int count;
> + struct ata_port *ap;
> + struct pi_adapter *pi;
> + char junk[2];
> +
> + /* We only need to flush incoming data when a command was running */
> + if (qc == NULL || qc->dma_dir == DMA_TO_DEVICE)
> + return;
> +
> + ap = qc->ap;
> + pi = ap->host->private_data;
> + /* Drain up to 64K of data before we give up this recovery method */
> + for (count = 0; (pata_parport_check_status(ap) & ATA_DRQ)
> + && count < 65536; count += 2) {
> + pi_connect(pi);
> + pi->proto->read_block(pi, junk, 2);
> + mod_timer(&pi->timer, jiffies + DISCONNECT_TIMEOUT);
> + }
> +
> + if (count)
> + ata_port_dbg(ap, "drained %d bytes to clear DRQ\n", count);
> +}
> +
> +static void pata_parport_lost_interrupt(struct ata_port *ap)
> +{
> + u8 status;
> + struct ata_queued_cmd *qc;
> +
> + /* Only one outstanding command per SFF channel */
> + qc = ata_qc_from_tag(ap, ap->link.active_tag);
> + /* We cannot lose an interrupt on a non-existent or polled command */
> + if (!qc || qc->tf.flags & ATA_TFLAG_POLLING)
> + return;
> + /*
> + * See if the controller thinks it is still busy - if so the command
> + * isn't a lost IRQ but is still in progress
> + */
> + status = pata_parport_check_altstatus(ap);
> + if (status & ATA_BUSY)
> + return;
> +
> + /*
> + * There was a command running, we are no longer busy and we have
> + * no interrupt.
> + */
> + ata_port_warn(ap, "lost interrupt (Status 0x%x)\n", status);
> + /* Run the host interrupt logic as if the interrupt had not been lost */
> + ata_sff_port_intr(ap, qc);
> +}
> +
> +static struct ata_port_operations pata_parport_port_ops = {
> + .inherits = &ata_sff_port_ops,
> +
> + .softreset = pata_parport_softreset,
> + .hardreset = NULL,
> +
> + .sff_dev_select = pata_parport_dev_select,
> + .sff_check_status = pata_parport_check_status,
> + .sff_check_altstatus = pata_parport_check_altstatus,
> + .sff_tf_load = pata_parport_tf_load,
> + .sff_tf_read = pata_parport_tf_read,
> + .sff_exec_command = pata_parport_exec_command,
> + .sff_data_xfer = pata_parport_data_xfer,
> + .sff_drain_fifo = pata_parport_drain_fifo,
> +
> + .lost_interrupt = pata_parport_lost_interrupt,
> +};
> +
> +static const struct ata_port_info pata_parport_port_info = {
> + .flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_PIO_POLLING,
> + .pio_mask = ATA_PIO0,
> + /* No DMA */
> + .port_ops = &pata_parport_port_ops,
> +};
> +
> +static void pi_release(struct pi_adapter *pi)
> +{
> + parport_unregister_device(pi->pardev);
> + if (pi->proto->release_proto)
> + pi->proto->release_proto(pi);
> + module_put(pi->proto->owner);
> +}
> +
> +static int default_test_proto(struct pi_adapter *pi, char *scratch)
> +{
> + int j, k;
> + int e[2] = { 0, 0 };
> +
> + pi->proto->connect(pi);
> +
> + for (j = 0; j < 2; j++) {
> + pi->proto->write_regr(pi, 0, 6, 0xa0 + j * 0x10);
> + for (k = 0; k < 256; k++) {
> + pi->proto->write_regr(pi, 0, 2, k ^ 0xaa);
> + pi->proto->write_regr(pi, 0, 3, k ^ 0x55);
> + if (pi->proto->read_regr(pi, 0, 2) != (k ^ 0xaa))
> + e[j]++;
> + }
> + }
> + pi->proto->disconnect(pi);
> +
> + if (verbose)
> + dev_info(&pi->dev, "%s: port 0x%x, mode %d, test=(%d,%d)\n",
> + pi->proto->name, pi->port,
> + pi->mode, e[0], e[1]);
> +
> + return e[0] && e[1]; /* not here if both > 0 */
> +}
> +
> +static int pi_test_proto(struct pi_adapter *pi, char *scratch)
> +{
> + int res;
> +
> + parport_claim_or_block(pi->pardev);
> + if (pi->proto->test_proto)
> + res = pi->proto->test_proto(pi, scratch, verbose);
> + else
> + res = default_test_proto(pi, scratch);
> + parport_release(pi->pardev);
> +
> + return res;
> +}
> +
> +static bool pi_probe_mode(struct pi_adapter *pi, int max, char *scratch)
> +{
> + int best, range;
> +
> + if (pi->mode != -1) {
> + if (pi->mode >= max)
> + return false;
> + range = 3;
> + if (pi->mode >= pi->proto->epp_first)
> + range = 8;
> + if (range == 8 && pi->port % 8)
> + return false;
> + return !pi_test_proto(pi, scratch);
> + }
> + best = -1;
> + for (pi->mode = 0; pi->mode < max; pi->mode++) {
> + range = 3;
> + if (pi->mode >= pi->proto->epp_first)
> + range = 8;
> + if (range == 8 && pi->port % 8)
> + break;
> + if (!pi_test_proto(pi, scratch))
> + best = pi->mode;
> + }
> + pi->mode = best;
> + return best > -1;
> +}
> +
> +static bool pi_probe_unit(struct pi_adapter *pi, int unit, char *scratch)
> +{
> + int max, s, e;
> +
> + s = unit;
> + e = s + 1;
> +
> + if (s == -1) {
> + s = 0;
> + e = pi->proto->max_units;
> + }
> +
> + if (pi->proto->test_port) {
> + parport_claim_or_block(pi->pardev);
> + max = pi->proto->test_port(pi);
> + parport_release(pi->pardev);
> + } else {
> + max = pi->proto->max_mode;
> + }
> +
> + if (pi->proto->probe_unit) {
> + parport_claim_or_block(pi->pardev);
> + for (pi->unit = s; pi->unit < e; pi->unit++) {
> + if (pi->proto->probe_unit(pi)) {
> + parport_release(pi->pardev);
> + return pi_probe_mode(pi, max, scratch);
> + }
> + }
> + parport_release(pi->pardev);
> + return false;
> + }
> +
> + return pi_probe_mode(pi, max, scratch);
> +}
> +
> +static void pata_parport_dev_release(struct device *dev)
> +{
> + struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev);
> +
> + kfree(pi);
> +}
> +
> +static void pata_parport_bus_release(struct device *dev)
> +{
> + /* nothing to do here but required to avoid warning on device removal */
> +}
> +
> +static struct bus_type pata_parport_bus_type = {
> + .name = DRV_NAME,
> +};
> +
> +static struct device pata_parport_bus = {
> + .init_name = DRV_NAME,
> + .release = pata_parport_bus_release,
> +};
> +
> +/* temporary for old paride protocol modules */
> +static struct scsi_host_template pata_parport_sht = {
> + PATA_PARPORT_SHT("pata_parport")
> +};
> +
> +static struct pi_adapter *pi_init_one(struct parport *parport,
> + struct pi_protocol *pr, int mode, int unit, int delay)
> +{
> + struct pardev_cb par_cb = { };
> + char scratch[512];
> + const struct ata_port_info *ppi[] = { &pata_parport_port_info };
> + struct ata_host *host;
> + struct pi_adapter *pi;
> +
> + pi = kzalloc(sizeof(struct pi_adapter), GFP_KERNEL);
> + if (!pi)
> + return NULL;
> +
> + /* set up pi->dev before pi_probe_unit() so it can use dev_printk() */
> + pi->dev.parent = &pata_parport_bus;
> + pi->dev.bus = &pata_parport_bus_type;
> + pi->dev.driver = &pr->driver;
> + pi->dev.release = pata_parport_dev_release;
> + pi->dev.id = ida_alloc(&pata_parport_bus_dev_ids, GFP_KERNEL);
> + if (pi->dev.id < 0)
> + return NULL; /* pata_parport_dev_release will do kfree(pi) */
> + dev_set_name(&pi->dev, "pata_parport.%u", pi->dev.id);
> + if (device_register(&pi->dev)) {
> + put_device(&pi->dev);
> + goto out_ida_free;
> + }
> +
> + pi->proto = pr;
> +
> + if (!try_module_get(pi->proto->owner))
> + goto out_unreg_dev;
> + if (pi->proto->init_proto && pi->proto->init_proto(pi) < 0)
> + goto out_module_put;
> +
> + pi->delay = (delay == -1) ? pi->proto->default_delay : delay;
> + pi->mode = mode;
> + pi->port = parport->base;
> +
> + par_cb.private = pi;
> + pi->pardev = parport_register_dev_model(parport, dev_name(&pi->dev),
> + &par_cb, pi->dev.id);
> + if (!pi->pardev)
> + goto out_module_put;
> +
> + if (!pi_probe_unit(pi, unit, scratch)) {
> + dev_info(&pi->dev, "Adapter not found\n");
> + goto out_unreg_parport;
> + }
> +
> + pi->proto->log_adapter(pi, scratch, verbose);
> +
> + host = ata_host_alloc_pinfo(&pi->dev, ppi, 1);
> + if (!host)
> + goto out_unreg_parport;
> + dev_set_drvdata(&pi->dev, host);
> + host->private_data = pi;
> +
> + ata_port_desc(host->ports[0], "port %s", pi->pardev->port->name);
> + ata_port_desc(host->ports[0], "protocol %s", pi->proto->name);
> +
> + timer_setup(&pi->timer, pi_disconnect_timer, 0);
> +
> + if (ata_host_activate(host, 0, NULL, 0, &pata_parport_sht))
> + goto out_unreg_parport;
> +
> + return pi;
> +
> +out_unreg_parport:
> + parport_unregister_device(pi->pardev);
> + if (pi->proto->release_proto)
> + pi->proto->release_proto(pi);
> +out_module_put:
> + module_put(pi->proto->owner);
> +out_unreg_dev:
> + device_unregister(&pi->dev);
> +out_ida_free:
> + ida_free(&pata_parport_bus_dev_ids, pi->dev.id);
> + return NULL;
> +}
> +
> +int pata_parport_register_driver(struct pi_protocol *pr)
> +{
> + int error;
> + struct parport *parport;
> + int port_num;
> +
> + pr->driver.bus = &pata_parport_bus_type;
> + pr->driver.name = pr->name;
> + error = driver_register(&pr->driver);
> + if (error)
> + return error;
> +
> + mutex_lock(&pi_mutex);
> + error = idr_alloc(&protocols, pr, 0, 0, GFP_KERNEL);
> + if (error < 0) {
> + driver_unregister(&pr->driver);
> + mutex_unlock(&pi_mutex);
> + return error;
> + }
> +
> + pr_info("pata_parport: protocol %s registered\n", pr->name);
> +
> + if (probe) {
> + /* probe all parports using this protocol */
> + idr_for_each_entry(&parport_list, parport, port_num)
> + pi_init_one(parport, pr, -1, 0, -1);
> + }
> + mutex_unlock(&pi_mutex);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL(pata_parport_register_driver);
> +
> +void pata_parport_unregister_driver(struct pi_protocol *pr)
> +{
> + struct pi_protocol *pr_iter;
> + int id = -1;
> +
> + mutex_lock(&pi_mutex);
> + idr_for_each_entry(&protocols, pr_iter, id) {
> + if (pr_iter == pr)
> + break;
> + }
> + idr_remove(&protocols, id);
> + mutex_unlock(&pi_mutex);
> + driver_unregister(&pr->driver);
> +}
> +EXPORT_SYMBOL(pata_parport_unregister_driver);
> +
> +static ssize_t new_device_store(struct bus_type *bus, const char *buf, size_t count)
> +{
> + char port[12] = "auto";
> + char protocol[8] = "auto";
> + int mode = -1, unit = -1, delay = -1;
> + struct pi_protocol *pr, *pr_wanted;
> + struct device_driver *drv;
> + struct parport *parport;
> + int port_num, port_wanted, pr_num;
> + bool ok = false;
> +
> + if (sscanf(buf, "%11s %7s %d %d %d",
> + port, protocol, &mode, &unit, &delay) < 1)
> + return -EINVAL;
> +
> + if (sscanf(port, "parport%u", &port_wanted) < 1) {
> + if (!strcmp(port, "auto")) {
> + port_wanted = -1;
> + } else {
> + pr_err("invalid port name %s\n", port);
> + return -EINVAL;
> + }
> + }
> +
> + drv = driver_find(protocol, &pata_parport_bus_type);
> + if (!drv) {
> + if (!strcmp(protocol, "auto")) {
> + pr_wanted = NULL;
> + } else {
> + pr_err("protocol %s not found\n", protocol);
> + return -EINVAL;
> + }
> + } else {
> + pr_wanted = container_of(drv, struct pi_protocol, driver);
> + }
> +
> + mutex_lock(&pi_mutex);
> + /* walk all parports */
> + idr_for_each_entry(&parport_list, parport, port_num) {
> + if (port_num == port_wanted || port_wanted == -1) {
> + parport = parport_find_number(port_num);
> + if (!parport) {
> + pr_err("no such port %s\n", port);
> + mutex_unlock(&pi_mutex);
> + return -ENODEV;
> + }
> + /* walk all protocols */
> + idr_for_each_entry(&protocols, pr, pr_num) {
> + if (pr == pr_wanted || !pr_wanted)
> + if (pi_init_one(parport, pr, mode, unit,
> + delay))
> + ok = true;
> + }
> + parport_put_port(parport);
> + }
> + }
> + mutex_unlock(&pi_mutex);
> + if (!ok)
> + return -ENODEV;
> +
> + return count;
> +}
> +static BUS_ATTR_WO(new_device);
> +
> +static void pi_remove_one(struct device *dev)
> +{
> + struct ata_host *host = dev_get_drvdata(dev);
> + struct pi_adapter *pi = host->private_data;
> +
> + ata_host_detach(host);
> + del_timer_sync(&pi->timer);
> + if (pi->claimed) {
> + pi->proto->disconnect(pi);
> + parport_release(pi->pardev);
> + }
> + pi_release(pi);
> + device_unregister(dev);
> + ida_free(&pata_parport_bus_dev_ids, dev->id);
> + /* pata_parport_dev_release will do kfree(pi) */
> +}
> +
> +static ssize_t delete_device_store(struct bus_type *bus, const char *buf, size_t count)
> +{
> + struct device *dev;
> + char device_name[32];
> +
> + if (sscanf(buf, "%31s", device_name) < 1)
> + return -EINVAL;
> +
> + mutex_lock(&pi_mutex);
> + dev = bus_find_device_by_name(bus, NULL, device_name);
> + if (!dev) {
> + mutex_unlock(&pi_mutex);
> + return -ENODEV;
> + }
> +
> + pi_remove_one(dev);
> + mutex_unlock(&pi_mutex);
> +
> + return count;
> +}
> +static BUS_ATTR_WO(delete_device);
> +
> +static void pata_parport_attach(struct parport *port)
> +{
> + struct pi_protocol *pr;
> + int pr_num, id;
> +
> + mutex_lock(&pi_mutex);
> + id = idr_alloc(&parport_list, port, port->number, port->number, GFP_KERNEL);
> + if (id < 0) {
> + mutex_unlock(&pi_mutex);
> + return;
> + }
> +
> + if (probe) {
> + /* probe this port using all protocols */
> + idr_for_each_entry(&protocols, pr, pr_num)
> + pi_init_one(port, pr, -1, 0, -1);
> + }
> + mutex_unlock(&pi_mutex);
> +}
> +
> +static int pi_remove_port(struct device *dev, void *p)
> +{
> + struct ata_host *host = dev_get_drvdata(dev);
> + struct pi_adapter *pi = host->private_data;
> +
> + if (pi->pardev->port == p)
> + pi_remove_one(dev);
> +
> + return 0;
> +}
> +
> +static void pata_parport_detach(struct parport *port)
> +{
> + mutex_lock(&pi_mutex);
> + bus_for_each_dev(&pata_parport_bus_type, NULL, port, pi_remove_port);
> + idr_remove(&parport_list, port->number);
> + mutex_unlock(&pi_mutex);
> +}
> +
> +static struct parport_driver pata_parport_driver = {
> + .name = DRV_NAME,
> + .match_port = pata_parport_attach,
> + .detach = pata_parport_detach,
> + .devmodel = true,
> +};
> +
> +static __init int pata_parport_init(void)
> +{
> + int error;
> +
> + error = bus_register(&pata_parport_bus_type);
> + if (error) {
> + pr_err("failed to register pata_parport bus, error: %d\n", error);
> + return error;
> + }
> +
> + error = device_register(&pata_parport_bus);
> + if (error) {
> + pr_err("failed to register pata_parport bus, error: %d\n", error);
> + goto out_unregister_bus;
> + }
> +
> + error = bus_create_file(&pata_parport_bus_type, &bus_attr_new_device);
> + if (error) {
> + pr_err("unable to create sysfs file, error: %d\n", error);
> + goto out_unregister_dev;
> + }
> +
> + error = bus_create_file(&pata_parport_bus_type, &bus_attr_delete_device);
> + if (error) {
> + pr_err("unable to create sysfs file, error: %d\n", error);
> + goto out_remove_new;
> + }
> +
> + error = parport_register_driver(&pata_parport_driver);
> + if (error) {
> + pr_err("unable to register parport driver, error: %d\n", error);
> + goto out_remove_del;
> + }
> +
> + return 0;
> +
> +out_remove_del:
> + bus_remove_file(&pata_parport_bus_type, &bus_attr_delete_device);
> +out_remove_new:
> + bus_remove_file(&pata_parport_bus_type, &bus_attr_new_device);
> +out_unregister_dev:
> + device_unregister(&pata_parport_bus);
> +out_unregister_bus:
> + bus_unregister(&pata_parport_bus_type);
> + return error;
> +}
> +
> +static __exit void pata_parport_exit(void)
> +{
> + parport_unregister_driver(&pata_parport_driver);
> + bus_remove_file(&pata_parport_bus_type, &bus_attr_new_device);
> + bus_remove_file(&pata_parport_bus_type, &bus_attr_delete_device);
> + device_unregister(&pata_parport_bus);
> + bus_unregister(&pata_parport_bus_type);
> +}
> +
> +MODULE_AUTHOR("Ondrej Zary");
> +MODULE_DESCRIPTION("driver for parallel port ATA adapters");
> +MODULE_LICENSE("GPL");
> +MODULE_ALIAS("paride");
> +
> +module_init(pata_parport_init);
> +module_exit(pata_parport_exit);
> diff --git a/drivers/ata/parport/pata_parport.h b/drivers/ata/parport/pata_parport.h
> new file mode 100644
> index 000000000000..d8d45f8bc742
> --- /dev/null
> +++ b/drivers/ata/parport/pata_parport.h
> @@ -0,0 +1,108 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * pata_parport.h (c) 1997-8 Grant R. Guenther <[email protected]>
> + * Under the terms of the GPL.
> + *
> + * This file defines the interface for parallell port IDE adapter chip drivers.
> + */
> +
> +#include <linux/libata.h>
> +
> +#define PI_PCD 1 /* dummy for paride protocol modules */
> +
> +struct pi_adapter {
> + struct device dev;
> + struct pi_protocol *proto; /* adapter protocol */
> + int port; /* base address of parallel port */
> + int mode; /* transfer mode in use */
> + int delay; /* adapter delay setting */
> + int devtype; /* dummy for paride protocol modules */
> + char *device; /* dummy for paride protocol modules */
> + int unit; /* unit number for chained adapters */
> + int saved_r0; /* saved port state */
> + int saved_r2; /* saved port state */
> + unsigned long private; /* for protocol module */
> + struct pardevice *pardev; /* pointer to pardevice */
> + bool claimed; /* parport has already been claimed */
> + struct timer_list timer; /* disconnect timer */
> +};
> +
> +typedef struct pi_adapter PIA; /* for paride protocol modules */
> +
> +/* registers are addressed as (cont,regr)
> + * cont: 0 for command register file, 1 for control register(s)
> + * regr: 0-7 for register number.
> + */
> +
> +/* macros and functions exported to the protocol modules */
> +#define delay_p (pi->delay ? udelay(pi->delay) : (void)0)
> +#define out_p(offs, byte) do { outb(byte, pi->port + offs); delay_p; } while (0)
> +#define in_p(offs) (delay_p, inb(pi->port + offs))
> +
> +#define w0(byte) out_p(0, byte)
> +#define r0() (in_p(0) & 0xff)
> +#define w1(byte) out_p(1, byte)
> +#define r1() (in_p(1) & 0xff)
> +#define w2(byte) out_p(2, byte)
> +#define r2() (in_p(2) & 0xff)
> +#define w3(byte) out_p(3, byte)
> +#define w4(byte) out_p(4, byte)
> +#define r4() (in_p(4) & 0xff)
> +#define w4w(data) do { outw(data, pi->port + 4); delay_p; } while (0)
> +#define w4l(data) do { outl(data, pi->port + 4); delay_p; } while (0)
> +#define r4w() (delay_p, inw(pi->port + 4) & 0xffff)
> +#define r4l() (delay_p, inl(pi->port + 4) & 0xffffffff)
> +
> +static inline u16 pi_swab16(char *b, int k)
> +{
> + union { u16 u; char t[2]; } r;
> +
> + r.t[0] = b[2 * k + 1]; r.t[1] = b[2 * k];
> + return r.u;
> +}
> +
> +static inline u32 pi_swab32(char *b, int k)
> +{
> + union { u32 u; char f[4]; } r;
> +
> + r.f[0] = b[4 * k + 1]; r.f[1] = b[4 * k];
> + r.f[2] = b[4 * k + 3]; r.f[3] = b[4 * k + 2];
> + return r.u;
> +}
> +
> +struct pi_protocol {
> + char name[8];
> +
> + int max_mode;
> + int epp_first; /* modes >= this use 8 ports */
> +
> + int default_delay;
> + int max_units; /* max chained units probed for */
> +
> + void (*write_regr)(struct pi_adapter *pi, int cont, int regr, int val);
> + int (*read_regr)(struct pi_adapter *pi, int cont, int regr);
> + void (*write_block)(struct pi_adapter *pi, char *buf, int count);
> + void (*read_block)(struct pi_adapter *pi, char *buf, int count);
> +
> + void (*connect)(struct pi_adapter *pi);
> + void (*disconnect)(struct pi_adapter *pi);
> +
> + int (*test_port)(struct pi_adapter *pi);
> + int (*probe_unit)(struct pi_adapter *pi);
> + int (*test_proto)(struct pi_adapter *pi, char *scratch, int verbose);
> + void (*log_adapter)(struct pi_adapter *pi, char *scratch, int verbose);
> +
> + int (*init_proto)(struct pi_adapter *pi);
> + void (*release_proto)(struct pi_adapter *pi);
> + struct module *owner;
> + struct device_driver driver;
> + struct scsi_host_template sht;
> +};
> +
> +#define PATA_PARPORT_SHT ATA_PIO_SHT
> +
> +int pata_parport_register_driver(struct pi_protocol *pr);
> +void pata_parport_unregister_driver(struct pi_protocol *pr);
> +/* defines for old paride protocol modules */
> +#define paride_register pata_parport_register_driver
> +#define paride_unregister pata_parport_unregister_driver
> diff --git a/drivers/block/paride/Kconfig b/drivers/block/paride/Kconfig
> index a295634597ba..01e4ef3655c1 100644
> --- a/drivers/block/paride/Kconfig
> +++ b/drivers/block/paride/Kconfig
> @@ -92,11 +92,11 @@ config PARIDE_PG
> later fully support this driver.
>
> comment "Parallel IDE protocol modules"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
>
> config PARIDE_ATEN
> tristate "ATEN EH-100 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the ATEN EH-100 parallel port IDE
> protocol. This protocol is used in some inexpensive low performance
> @@ -109,7 +109,7 @@ config PARIDE_ATEN
>
> config PARIDE_BPCK
> tristate "MicroSolutions backpack (Series 5) protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the Micro Solutions BACKPACK
> parallel port Series 5 IDE protocol. (Most BACKPACK drives made
> @@ -127,7 +127,7 @@ config PARIDE_BPCK
>
> config PARIDE_BPCK6
> tristate "MicroSolutions backpack (Series 6) protocol"
> - depends on PARIDE && !64BIT
> + depends on (PARIDE || PATA_PARPORT) && !64BIT
> help
> This option enables support for the Micro Solutions BACKPACK
> parallel port Series 6 IDE protocol. (Most BACKPACK drives made
> @@ -146,7 +146,7 @@ config PARIDE_BPCK6
>
> config PARIDE_COMM
> tristate "DataStor Commuter protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the Commuter parallel port IDE
> protocol from DataStor. If you chose to build PARIDE support
> @@ -157,7 +157,7 @@ config PARIDE_COMM
>
> config PARIDE_DSTR
> tristate "DataStor EP-2000 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the EP-2000 parallel port IDE
> protocol from DataStor. If you chose to build PARIDE support
> @@ -168,7 +168,7 @@ config PARIDE_DSTR
>
> config PARIDE_FIT2
> tristate "FIT TD-2000 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the TD-2000 parallel port IDE
> protocol from Fidelity International Technology. This is a simple
> @@ -181,7 +181,7 @@ config PARIDE_FIT2
>
> config PARIDE_FIT3
> tristate "FIT TD-3000 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the TD-3000 parallel port IDE
> protocol from Fidelity International Technology. This protocol is
> @@ -194,7 +194,7 @@ config PARIDE_FIT3
>
> config PARIDE_EPAT
> tristate "Shuttle EPAT/EPEZ protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the EPAT parallel port IDE protocol.
> EPAT is a parallel port IDE adapter manufactured by Shuttle
> @@ -216,7 +216,7 @@ config PARIDE_EPATC8
>
> config PARIDE_EPIA
> tristate "Shuttle EPIA protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the (obsolete) EPIA parallel port
> IDE protocol from Shuttle Technology. This adapter can still be
> @@ -228,7 +228,7 @@ config PARIDE_EPIA
>
> config PARIDE_FRIQ
> tristate "Freecom IQ ASIC-2 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for version 2 of the Freecom IQ parallel
> port IDE adapter. This adapter is used by the Maxell Superdisk
> @@ -240,7 +240,7 @@ config PARIDE_FRIQ
>
> config PARIDE_FRPW
> tristate "FreeCom power protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the Freecom power parallel port IDE
> protocol. If you chose to build PARIDE support into your kernel, you
> @@ -251,7 +251,7 @@ config PARIDE_FRPW
>
> config PARIDE_KBIC
> tristate "KingByte KBIC-951A/971A protocols"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the KBIC-951A and KBIC-971A parallel
> port IDE protocols from KingByte Information Corp. KingByte's
> @@ -264,7 +264,7 @@ config PARIDE_KBIC
>
> config PARIDE_KTTI
> tristate "KT PHd protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the "PHd" parallel port IDE protocol
> from KT Technology. This is a simple (low speed) adapter that is
> @@ -277,7 +277,7 @@ config PARIDE_KTTI
>
> config PARIDE_ON20
> tristate "OnSpec 90c20 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the (obsolete) 90c20 parallel port
> IDE protocol from OnSpec (often marketed under the ValuStore brand
> @@ -289,7 +289,7 @@ config PARIDE_ON20
>
> config PARIDE_ON26
> tristate "OnSpec 90c26 protocol"
> - depends on PARIDE
> + depends on PARIDE || PATA_PARPORT
> help
> This option enables support for the 90c26 parallel port IDE protocol
> from OnSpec Electronics (often marketed under the ValuStore brand
> diff --git a/drivers/block/paride/paride.h b/drivers/block/paride/paride.h
> index ddb9e589da7f..f3bd01a9c9ec 100644
> --- a/drivers/block/paride/paride.h
> +++ b/drivers/block/paride/paride.h
> @@ -1,3 +1,7 @@
> +#if IS_ENABLED(CONFIG_PATA_PARPORT)
> +#include "../../ata/parport/pata_parport.h"
> +
> +#else
> #ifndef __DRIVERS_PARIDE_H__
> #define __DRIVERS_PARIDE_H__
>
> @@ -170,3 +174,4 @@ void pi_unregister_driver(void *);
>
> #endif /* __DRIVERS_PARIDE_H__ */
> /* end of paride.h */
> +#endif /* IS_ENABLED(CONFIG_PATA_PARPORT) */


--
Damien Le Moal
Western Digital Research

2022-03-11 22:17:51

by Ondrej Zary

[permalink] [raw]
Subject: Re: [PATCH v0] pata_parport: add driver (PARIDE replacement)

On Friday 11 March 2022 00:59:20 Damien Le Moal wrote:
> On 3/11/22 06:28, Ondrej Zary wrote:
> > Add pata_parport (PARIDE replacement) core libata driver.
> >
> > The original paride protocol modules are used for now so allow them to
> > be compiled without old PARIDE core.
> >
> > Signed-off-by: Ondrej Zary <[email protected]>
> > ---
> > drivers/Makefile | 2 +-
> > drivers/ata/Kconfig | 22 +
> > drivers/ata/Makefile | 2 +
> > drivers/ata/parport/Makefile | 3 +
> > drivers/ata/parport/pata_parport.c | 805 +++++++++++++++++++++++++++++
> > drivers/ata/parport/pata_parport.h | 108 ++++
> > drivers/block/paride/Kconfig | 32 +-
> > drivers/block/paride/paride.h | 5 +
> > 8 files changed, 962 insertions(+), 17 deletions(-)
> > create mode 100644 drivers/ata/parport/Makefile
> > create mode 100644 drivers/ata/parport/pata_parport.c
> > create mode 100644 drivers/ata/parport/pata_parport.h
> >
> > diff --git a/drivers/Makefile b/drivers/Makefile
> > index a110338c860c..8ec515f3614e 100644
> > --- a/drivers/Makefile
> > +++ b/drivers/Makefile
> > @@ -98,7 +98,7 @@ obj-$(CONFIG_DIO) += dio/
> > obj-$(CONFIG_SBUS) += sbus/
> > obj-$(CONFIG_ZORRO) += zorro/
> > obj-$(CONFIG_ATA_OVER_ETH) += block/aoe/
> > -obj-$(CONFIG_PARIDE) += block/paride/
> > +obj-y += block/paride/
> > obj-$(CONFIG_TC) += tc/
> > obj-$(CONFIG_USB_PHY) += usb/
> > obj-$(CONFIG_USB) += usb/
> > diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> > index e5641e6c52ee..671c27b77a48 100644
> > --- a/drivers/ata/Kconfig
> > +++ b/drivers/ata/Kconfig
> > @@ -1161,6 +1161,28 @@ config PATA_WINBOND_VLB
> > Support for the Winbond W83759A controller on Vesa Local Bus
> > systems.
> >
> > +config PATA_PARPORT
> > + tristate "Parallel port IDE device support"
> > + depends on PARPORT_PC && PARIDE=n
>
> This is very confusing. The change above this one switch paride
> compilation to be unconditional, regardless of CONFIG_PARIDE value, but
> here, you have the dependency to PARIDE=n. I do not understand... Please
> clarify.

pata_parport will use existing paride protocol modules. So the paride/ directory must be processed to compile the protocol modules (if they're enabled) even if paride is not enabled.

pata_parport and paride are mutually exclusive because the binary protocol modules are incompatible (the struct pi_adapter is different).

--
Ondrej Zary

2022-03-12 11:41:59

by Damien Le Moal

[permalink] [raw]
Subject: Re: [PATCH v0] pata_parport: add driver (PARIDE replacement)

On 3/12/22 03:55, Ondrej Zary wrote:
> On Friday 11 March 2022 00:59:20 Damien Le Moal wrote:
>> On 3/11/22 06:28, Ondrej Zary wrote:
>>> Add pata_parport (PARIDE replacement) core libata driver.
>>>
>>> The original paride protocol modules are used for now so allow them to
>>> be compiled without old PARIDE core.
>>>
>>> Signed-off-by: Ondrej Zary <[email protected]>
>>> ---
>>> drivers/Makefile | 2 +-
>>> drivers/ata/Kconfig | 22 +
>>> drivers/ata/Makefile | 2 +
>>> drivers/ata/parport/Makefile | 3 +
>>> drivers/ata/parport/pata_parport.c | 805 +++++++++++++++++++++++++++++
>>> drivers/ata/parport/pata_parport.h | 108 ++++
>>> drivers/block/paride/Kconfig | 32 +-
>>> drivers/block/paride/paride.h | 5 +
>>> 8 files changed, 962 insertions(+), 17 deletions(-)
>>> create mode 100644 drivers/ata/parport/Makefile
>>> create mode 100644 drivers/ata/parport/pata_parport.c
>>> create mode 100644 drivers/ata/parport/pata_parport.h
>>>
>>> diff --git a/drivers/Makefile b/drivers/Makefile
>>> index a110338c860c..8ec515f3614e 100644
>>> --- a/drivers/Makefile
>>> +++ b/drivers/Makefile
>>> @@ -98,7 +98,7 @@ obj-$(CONFIG_DIO) += dio/
>>> obj-$(CONFIG_SBUS) += sbus/
>>> obj-$(CONFIG_ZORRO) += zorro/
>>> obj-$(CONFIG_ATA_OVER_ETH) += block/aoe/
>>> -obj-$(CONFIG_PARIDE) += block/paride/
>>> +obj-y += block/paride/
>>> obj-$(CONFIG_TC) += tc/
>>> obj-$(CONFIG_USB_PHY) += usb/
>>> obj-$(CONFIG_USB) += usb/
>>> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
>>> index e5641e6c52ee..671c27b77a48 100644
>>> --- a/drivers/ata/Kconfig
>>> +++ b/drivers/ata/Kconfig
>>> @@ -1161,6 +1161,28 @@ config PATA_WINBOND_VLB
>>> Support for the Winbond W83759A controller on Vesa Local Bus
>>> systems.
>>>
>>> +config PATA_PARPORT
>>> + tristate "Parallel port IDE device support"
>>> + depends on PARPORT_PC && PARIDE=n
>>
>> This is very confusing. The change above this one switch paride
>> compilation to be unconditional, regardless of CONFIG_PARIDE value, but
>> here, you have the dependency to PARIDE=n. I do not understand... Please
>> clarify.
>
> pata_parport will use existing paride protocol modules. So the paride/ directory must be processed to compile the protocol modules (if they're enabled) even if paride is not enabled.
>
> pata_parport and paride are mutually exclusive because the binary protocol modules are incompatible (the struct pi_adapter is different).

So if both CONFIG_PARIDE and CONFIG_PATA_PARPORT are disabled, there
should be no need to compile the core PARIDE code under block/. You
should have something like:

In drivers/Makefile:

-obj-$(CONFIG_PARIDE) += block/paride/
+obj-$(CONFIG_PARIDE_CORE) += block/paride/

And then have CONFIG_PARIDE and CONFIG_PATA_PARPORT select PARIDE_CORE,
with CONFIG_PARIDE and CONFIG_PATA_PARPORT being mutually exclusive
(using "depends on" as you did).

Here, I am assuming that block/paride is the core code used by both
PARIDE and PATA_PARPORT. Not sure what PARPORT_PC does nor what its
dependency on block/paride code is.


--
Damien Le Moal
Western Digital Research

2022-03-13 10:41:23

by Ondrej Zary

[permalink] [raw]
Subject: Re: [PATCH v0] pata_parport: add driver (PARIDE replacement)


On Saturday 12 March 2022 09:09:54 Damien Le Moal wrote:
> On 3/12/22 03:55, Ondrej Zary wrote:
> > On Friday 11 March 2022 00:59:20 Damien Le Moal wrote:
> >> On 3/11/22 06:28, Ondrej Zary wrote:
> >>> Add pata_parport (PARIDE replacement) core libata driver.
> >>>
> >>> The original paride protocol modules are used for now so allow them to
> >>> be compiled without old PARIDE core.
> >>>
> >>> Signed-off-by: Ondrej Zary <[email protected]>
> >>> ---
> >>> drivers/Makefile | 2 +-
> >>> drivers/ata/Kconfig | 22 +
> >>> drivers/ata/Makefile | 2 +
> >>> drivers/ata/parport/Makefile | 3 +
> >>> drivers/ata/parport/pata_parport.c | 805 +++++++++++++++++++++++++++++
> >>> drivers/ata/parport/pata_parport.h | 108 ++++
> >>> drivers/block/paride/Kconfig | 32 +-
> >>> drivers/block/paride/paride.h | 5 +
> >>> 8 files changed, 962 insertions(+), 17 deletions(-)
> >>> create mode 100644 drivers/ata/parport/Makefile
> >>> create mode 100644 drivers/ata/parport/pata_parport.c
> >>> create mode 100644 drivers/ata/parport/pata_parport.h
> >>>
> >>> diff --git a/drivers/Makefile b/drivers/Makefile
> >>> index a110338c860c..8ec515f3614e 100644
> >>> --- a/drivers/Makefile
> >>> +++ b/drivers/Makefile
> >>> @@ -98,7 +98,7 @@ obj-$(CONFIG_DIO) += dio/
> >>> obj-$(CONFIG_SBUS) += sbus/
> >>> obj-$(CONFIG_ZORRO) += zorro/
> >>> obj-$(CONFIG_ATA_OVER_ETH) += block/aoe/
> >>> -obj-$(CONFIG_PARIDE) += block/paride/
> >>> +obj-y += block/paride/
> >>> obj-$(CONFIG_TC) += tc/
> >>> obj-$(CONFIG_USB_PHY) += usb/
> >>> obj-$(CONFIG_USB) += usb/
> >>> diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
> >>> index e5641e6c52ee..671c27b77a48 100644
> >>> --- a/drivers/ata/Kconfig
> >>> +++ b/drivers/ata/Kconfig
> >>> @@ -1161,6 +1161,28 @@ config PATA_WINBOND_VLB
> >>> Support for the Winbond W83759A controller on Vesa Local Bus
> >>> systems.
> >>>
> >>> +config PATA_PARPORT
> >>> + tristate "Parallel port IDE device support"
> >>> + depends on PARPORT_PC && PARIDE=n
> >>
> >> This is very confusing. The change above this one switch paride
> >> compilation to be unconditional, regardless of CONFIG_PARIDE value, but
> >> here, you have the dependency to PARIDE=n. I do not understand... Please
> >> clarify.
> >
> > pata_parport will use existing paride protocol modules. So the paride/ directory must be processed to compile the protocol modules (if they're enabled) even if paride is not enabled.
> >
> > pata_parport and paride are mutually exclusive because the binary protocol modules are incompatible (the struct pi_adapter is different).
>
> So if both CONFIG_PARIDE and CONFIG_PATA_PARPORT are disabled, there
> should be no need to compile the core PARIDE code under block/. You
> should have something like:
>
> In drivers/Makefile:
>
> -obj-$(CONFIG_PARIDE) += block/paride/
> +obj-$(CONFIG_PARIDE_CORE) += block/paride/
>
> And then have CONFIG_PARIDE and CONFIG_PATA_PARPORT select PARIDE_CORE,
> with CONFIG_PARIDE and CONFIG_PATA_PARPORT being mutually exclusive
> (using "depends on" as you did).
>
> Here, I am assuming that block/paride is the core code used by both
> PARIDE and PATA_PARPORT. Not sure what PARPORT_PC does nor what its
> dependency on block/paride code is.

There's no common core in block/paride. The block/paride/Makefile says:
obj-$(CONFIG_PARIDE) += paride.o
obj-$(CONFIG_PARIDE_ATEN) += aten.o
obj-$(CONFIG_PARIDE_...other protocol drivers

So if PARIDE and all protocol drivers are disabled, nothing is compiled there.

--
Ondrej Zary

2022-03-17 06:07:56

by Christoph Hellwig

[permalink] [raw]
Subject: Re: [PATCH v0] pata_parport: add driver (PARIDE replacement)

On Sat, Mar 12, 2022 at 12:21:55PM +0100, Ondrej Zary wrote:
> > Here, I am assuming that block/paride is the core code used by both
> > PARIDE and PATA_PARPORT. Not sure what PARPORT_PC does nor what its
> > dependency on block/paride code is.
>
> There's no common core in block/paride. The block/paride/Makefile says:
> obj-$(CONFIG_PARIDE) += paride.o
> obj-$(CONFIG_PARIDE_ATEN) += aten.o
> obj-$(CONFIG_PARIDE_...other protocol drivers
>
> So if PARIDE and all protocol drivers are disabled, nothing is compiled there.

Yeah. The pattern of unconditionally descending into a subdirectory
isn't entirely uncommon. I think this is perfectly fine here.