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

Damien Le Moal
2022-03-11T00:27:56Z

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 <linux@zary.sk>
> ---
> 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 <grant@torque.net>
> + * 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