diff options
Diffstat (limited to 'drivers/parport/parport_amiga.c')
| -rw-r--r-- | drivers/parport/parport_amiga.c | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/drivers/parport/parport_amiga.c b/drivers/parport/parport_amiga.c new file mode 100644 index 000000000..84d5701d6 --- /dev/null +++ b/drivers/parport/parport_amiga.c @@ -0,0 +1,245 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Low-level parallel port routines for the Amiga built-in port + * + * Author: Joerg Dorchain <joerg@dorchain.net> + * + * This is a complete rewrite of the code, but based heaviy upon the old + * lp_intern. code. + * + * The built-in Amiga parallel port provides one port at a fixed address + * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status + * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically + * in hardware when the data register is accessed), and 1 input control line + * /ACK, able to cause an interrupt, but both not directly settable by + * software. + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/parport.h> +#include <linux/ioport.h> +#include <linux/interrupt.h> +#include <linux/platform_device.h> + +#include <asm/setup.h> +#include <asm/amigahw.h> +#include <asm/irq.h> +#include <asm/io.h> +#include <asm/amigaints.h> + +#undef DEBUG + +static void amiga_write_data(struct parport *p, unsigned char data) +{ + pr_debug("write_data %c\n", data); + /* Triggers also /STROBE. This behavior cannot be changed */ + ciaa.prb = data; + mb(); +} + +static unsigned char amiga_read_data(struct parport *p) +{ + /* Triggers also /STROBE. This behavior cannot be changed */ + return ciaa.prb; +} + +static unsigned char control_amiga_to_pc(unsigned char control) +{ + return PARPORT_CONTROL_SELECT | + PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE; + /* fake value: interrupt enable, select in, no reset, + no autolf, no strobe - seems to be closest the wiring diagram */ +} + +static void amiga_write_control(struct parport *p, unsigned char control) +{ + pr_debug("write_control %02x\n", control); + /* No implementation possible */ +} + +static unsigned char amiga_read_control( struct parport *p) +{ + pr_debug("read_control\n"); + return control_amiga_to_pc(0); +} + +static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val) +{ + unsigned char old; + + pr_debug("frob_control mask %02x, value %02x\n", mask, val); + old = amiga_read_control(p); + amiga_write_control(p, (old & ~mask) ^ val); + return old; +} + +static unsigned char status_amiga_to_pc(unsigned char status) +{ + unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR; + + if (status & 1) /* Busy */ + ret &= ~PARPORT_STATUS_BUSY; + if (status & 2) /* PaperOut */ + ret |= PARPORT_STATUS_PAPEROUT; + if (status & 4) /* Selected */ + ret |= PARPORT_STATUS_SELECT; + /* the rest is not connected or handled autonomously in hardware */ + + return ret; +} + +static unsigned char amiga_read_status(struct parport *p) +{ + unsigned char status; + + status = status_amiga_to_pc(ciab.pra & 7); + pr_debug("read_status %02x\n", status); + return status; +} + +static void amiga_enable_irq(struct parport *p) +{ + enable_irq(IRQ_AMIGA_CIAA_FLG); +} + +static void amiga_disable_irq(struct parport *p) +{ + disable_irq(IRQ_AMIGA_CIAA_FLG); +} + +static void amiga_data_forward(struct parport *p) +{ + pr_debug("forward\n"); + ciaa.ddrb = 0xff; /* all pins output */ + mb(); +} + +static void amiga_data_reverse(struct parport *p) +{ + pr_debug("reverse\n"); + ciaa.ddrb = 0; /* all pins input */ + mb(); +} + +static void amiga_init_state(struct pardevice *dev, struct parport_state *s) +{ + s->u.amiga.data = 0; + s->u.amiga.datadir = 255; + s->u.amiga.status = 0; + s->u.amiga.statusdir = 0; +} + +static void amiga_save_state(struct parport *p, struct parport_state *s) +{ + mb(); + s->u.amiga.data = ciaa.prb; + s->u.amiga.datadir = ciaa.ddrb; + s->u.amiga.status = ciab.pra & 7; + s->u.amiga.statusdir = ciab.ddra & 7; + mb(); +} + +static void amiga_restore_state(struct parport *p, struct parport_state *s) +{ + mb(); + ciaa.prb = s->u.amiga.data; + ciaa.ddrb = s->u.amiga.datadir; + ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status; + ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir; + mb(); +} + +static struct parport_operations pp_amiga_ops = { + .write_data = amiga_write_data, + .read_data = amiga_read_data, + + .write_control = amiga_write_control, + .read_control = amiga_read_control, + .frob_control = amiga_frob_control, + + .read_status = amiga_read_status, + + .enable_irq = amiga_enable_irq, + .disable_irq = amiga_disable_irq, + + .data_forward = amiga_data_forward, + .data_reverse = amiga_data_reverse, + + .init_state = amiga_init_state, + .save_state = amiga_save_state, + .restore_state = amiga_restore_state, + + .epp_write_data = parport_ieee1284_epp_write_data, + .epp_read_data = parport_ieee1284_epp_read_data, + .epp_write_addr = parport_ieee1284_epp_write_addr, + .epp_read_addr = parport_ieee1284_epp_read_addr, + + .ecp_write_data = parport_ieee1284_ecp_write_data, + .ecp_read_data = parport_ieee1284_ecp_read_data, + .ecp_write_addr = parport_ieee1284_ecp_write_addr, + + .compat_write_data = parport_ieee1284_write_compat, + .nibble_read_data = parport_ieee1284_read_nibble, + .byte_read_data = parport_ieee1284_read_byte, + + .owner = THIS_MODULE, +}; + +/* ----------- Initialisation code --------------------------------- */ + +static int __init amiga_parallel_probe(struct platform_device *pdev) +{ + struct parport *p; + int err; + + ciaa.ddrb = 0xff; + ciab.ddra &= 0xf8; + mb(); + + p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG, + PARPORT_DMA_NONE, &pp_amiga_ops); + if (!p) + return -EBUSY; + + err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name, + p); + if (err) + goto out_irq; + + pr_info("%s: Amiga built-in port using irq\n", p->name); + /* XXX: set operating mode */ + parport_announce_port(p); + + platform_set_drvdata(pdev, p); + + return 0; + +out_irq: + parport_put_port(p); + return err; +} + +static int __exit amiga_parallel_remove(struct platform_device *pdev) +{ + struct parport *port = platform_get_drvdata(pdev); + + parport_remove_port(port); + if (port->irq != PARPORT_IRQ_NONE) + free_irq(IRQ_AMIGA_CIAA_FLG, port); + parport_put_port(port); + return 0; +} + +static struct platform_driver amiga_parallel_driver = { + .remove = __exit_p(amiga_parallel_remove), + .driver = { + .name = "amiga-parallel", + }, +}; + +module_platform_driver_probe(amiga_parallel_driver, amiga_parallel_probe); + +MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>"); +MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:amiga-parallel"); |