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SubjectRe: [PATCH] pata_parport: add driver (PARIDE replacement)
From
On 11/14/22 16:53, Ondrej Zary wrote:
> On Monday 14 November 2022, Damien Le Moal wrote:
>> On 11/12/22 20:17, Ondrej Zary wrote:
>>> On Wednesday 19 October 2022 09:34:31 Christoph Hellwig wrote:
>>>> It's been a while - did you get a chance to make some progress on
>>>> this? Do you need any help to unblock you?
>>>>
>>>
>>> Sorry again, I'm back now. Trying to fix locking problems.
>>> Added this to each function for analysis how the functions are called wrt.
>>> locking:
>>>
>>> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
>>
>> Do you have your code somewhere that we can look at ?
>
> This is the current version with debug printks. I've also added dump_stack()
> to find out the code path but haven't analyzed the output yet.

Can you send a proper patch ? Or a link to a git tree ? That is easier to
handle than pasted code in an email...

>
> // SPDX-License-Identifier: GPL-2.0-only
> /*
> * Copyright 2022 Ondrej Zary
> * based on paride.c by Grant R. Guenther <grant@torque.net>
> */
> #include <linux/kernel.h>
> #include <linux/module.h>
> #include <linux/parport.h>
> #include <linux/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 ata_port *ap)
> {
> struct pi_adapter *pi = ap->host->private_data;
> if (spin_is_locked(ap->lock))
> dump_stack();
>
> 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(struct pi_adapter *pi)
> {
> if (pi->claimed) {
> pi->proto->disconnect(pi);
> parport_release(pi->pardev);
> pi->claimed = false;
> }
> }
>
> static void pi_disconnect_timer(struct timer_list *t)
> {
> struct pi_adapter *pi = from_timer(pi, t, timer);
>
> pi_disconnect(pi);
> }
>
> /* 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
>
> if (device == 0)
> tmp = ATA_DEVICE_OBS;
> else
> tmp = ATA_DEVICE_OBS | ATA_DEV1;
>
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pata_parport_dev_select(ap, device);
>
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> /* 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> /* 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> pi_connect(ap);
> 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;
> printk("%s, locked=%d\n", __FUNCTION__, spin_is_locked(ap->lock));
> 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(ap);
> 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 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,
> };
>
> 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")
> };
>
> struct pi_device_match {
> struct parport *parport;
> struct pi_protocol *proto;
> };
>
> static int pi_find_dev(struct device *dev, void *data)
> {
> struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev);
> struct pi_device_match *match = data;
>
> return pi->pardev->port == match->parport && pi->proto == match->proto;
> }
>
> 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;
> struct pi_device_match match = { .parport = parport, .proto = pr };
>
> /*
> * Abort if there's a device already registered on the same parport
> * using the same protocol.
> */
> if (bus_for_each_dev(&pata_parport_bus_type, NULL, &match, pi_find_dev))
> return NULL;
>
> 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, DRV_NAME, &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->pardev->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);
> pi_disconnect(pi);
> 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);
>
>
>

--
Damien Le Moal
Western Digital Research

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