// SPDX-License-Identifier: GPL-2.0-only /* * Copyright 2023 Ondrej Zary * based on paride.c by Grant R. Guenther */ #include #include #include #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])"); /* * libata drivers cannot sleep so this driver claims parport before activating * the ata host and keeps it claimed (and protocol connected) until the ata * host is removed. Unfortunately, this means that you cannot use any chained * devices (neither other pata_parport devices nor a printer). */ static void pi_connect(struct pi_adapter *pi) { parport_claim_or_block(pi->pardev); pi->proto->connect(pi); } static void pi_disconnect(struct pi_adapter *pi) { pi->proto->disconnect(pi); parport_release(pi->pardev); } 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->proto->write_regr(pi, 0, ATA_REG_DEVICE, tmp); ata_sff_pause(ap); } static void pata_parport_set_devctl(struct ata_port *ap, u8 ctl) { struct pi_adapter *pi = ap->host->private_data; pi->proto->write_regr(pi, 1, 6, ctl); } 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->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, 0x55); 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); return (nsect == 0x55) && (lbal == 0xaa); } static int pata_parport_bus_softreset(struct ata_port *ap, unsigned int devmask, unsigned long deadline) { struct pi_adapter *pi = ap->host->private_data; /* 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; /* 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) { struct pi_adapter *pi = ap->host->private_data; return pi->proto->read_regr(pi, 0, ATA_REG_STATUS); } static u8 pata_parport_check_altstatus(struct ata_port *ap) { struct pi_adapter *pi = ap->host->private_data; return pi->proto->read_regr(pi, 1, 6); } static void pata_parport_tf_load(struct ata_port *ap, const struct ata_taskfile *tf) { struct pi_adapter *pi = ap->host->private_data; 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); } static void pata_parport_tf_read(struct ata_port *ap, struct ata_taskfile *tf) { struct pi_adapter *pi = ap->host->private_data; 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; } } static void pata_parport_exec_command(struct ata_port *ap, const struct ata_taskfile *tf) { struct pi_adapter *pi = ap->host->private_data; pi->proto->write_regr(pi, 0, ATA_REG_CMD, tf->command); ata_sff_pause(ap); } 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; if (rw == READ) pi->proto->read_block(pi, buf, buflen); else pi->proto->write_block(pi, buf, buflen); 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->proto->read_block(pi, junk, 2); } 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_set_devctl = pata_parport_set_devctl, .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) { 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); dev_dbg(&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) { int res; parport_claim_or_block(pi->pardev); if (pi->proto->test_proto) res = pi->proto->test_proto(pi); else res = default_test_proto(pi); parport_release(pi->pardev); return res; } static bool pi_probe_mode(struct pi_adapter *pi, int max) { 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); } 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)) best = pi->mode; } pi->mode = best; return best > -1; } static bool pi_probe_unit(struct pi_adapter *pi, int unit) { 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); } } parport_release(pi->pardev); return false; } return pi_probe_mode(pi, max); } static void pata_parport_dev_release(struct device *dev) { struct pi_adapter *pi = container_of(dev, struct pi_adapter, dev); ida_free(&pata_parport_bus_dev_ids, dev->id); 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, }; static const 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 = { }; 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 }; int id; /* * 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; id = ida_alloc(&pata_parport_bus_dev_ids, GFP_KERNEL); if (id < 0) return NULL; pi = kzalloc(sizeof(struct pi_adapter), GFP_KERNEL); if (!pi) { ida_free(&pata_parport_bus_dev_ids, id); 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 = id; dev_set_name(&pi->dev, "pata_parport.%u", pi->dev.id); if (device_register(&pi->dev)) { put_device(&pi->dev); /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */ return NULL; } 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, id); if (!pi->pardev) goto out_module_put; if (!pi_probe_unit(pi, unit)) { dev_info(&pi->dev, "Adapter not found\n"); goto out_unreg_parport; } pi->proto->log_adapter(pi); 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); pi_connect(pi); if (ata_host_activate(host, 0, NULL, 0, &pata_parport_sht)) goto out_disconnect; return pi; out_disconnect: pi_disconnect(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); /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */ 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, -1, -1); } mutex_unlock(&pi_mutex); return 0; } EXPORT_SYMBOL_GPL(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_GPL(pata_parport_unregister_driver); static ssize_t new_device_store(const 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")) { pr_err("invalid port name %s\n", port); return -EINVAL; } port_wanted = -1; } drv = driver_find(protocol, &pata_parport_bus_type); if (!drv) { if (strcmp(protocol, "auto")) { pr_err("protocol %s not found\n", protocol); return -EINVAL; } pr_wanted = NULL; } 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); pi_disconnect(pi); pi_release(pi); device_unregister(dev); /* pata_parport_dev_release will do ida_free(dev->id) and kfree(pi) */ } static ssize_t delete_device_store(const struct bus_type *bus, const char *buf, size_t count) { struct device *dev; mutex_lock(&pi_mutex); dev = bus_find_device_by_name(bus, NULL, buf); if (!dev) { mutex_unlock(&pi_mutex); return -ENODEV; } pi_remove_one(dev); put_device(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, -1, -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);