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1// SPDX-License-Identifier: GPL-2.0-only2/* Low-level parallel port routines for the Amiga built-in port3 *4 * Author: Joerg Dorchain <joerg@dorchain.net>5 *6 * This is a complete rewrite of the code, but based heaviy upon the old7 * lp_intern. code.8 *9 * The built-in Amiga parallel port provides one port at a fixed address10 * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status11 * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically12 * in hardware when the data register is accessed), and 1 input control line13 * /ACK, able to cause an interrupt, but both not directly settable by14 * software.15 */16 17#include <linux/module.h>18#include <linux/init.h>19#include <linux/parport.h>20#include <linux/ioport.h>21#include <linux/interrupt.h>22#include <linux/platform_device.h>23 24#include <asm/setup.h>25#include <asm/amigahw.h>26#include <asm/irq.h>27#include <asm/io.h>28#include <asm/amigaints.h>29 30#undef DEBUG31 32static void amiga_write_data(struct parport *p, unsigned char data)33{34 pr_debug("write_data %c\n", data);35 /* Triggers also /STROBE. This behavior cannot be changed */36 ciaa.prb = data;37 mb();38}39 40static unsigned char amiga_read_data(struct parport *p)41{42 /* Triggers also /STROBE. This behavior cannot be changed */43 return ciaa.prb;44}45 46static unsigned char control_amiga_to_pc(unsigned char control)47{48 return PARPORT_CONTROL_SELECT |49 PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE;50 /* fake value: interrupt enable, select in, no reset,51 no autolf, no strobe - seems to be closest the wiring diagram */52}53 54static void amiga_write_control(struct parport *p, unsigned char control)55{56 pr_debug("write_control %02x\n", control);57 /* No implementation possible */58}59 60static unsigned char amiga_read_control( struct parport *p)61{62 pr_debug("read_control\n");63 return control_amiga_to_pc(0);64}65 66static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val)67{68 unsigned char old;69 70 pr_debug("frob_control mask %02x, value %02x\n", mask, val);71 old = amiga_read_control(p);72 amiga_write_control(p, (old & ~mask) ^ val);73 return old;74}75 76static unsigned char status_amiga_to_pc(unsigned char status)77{78 unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR;79 80 if (status & 1) /* Busy */81 ret &= ~PARPORT_STATUS_BUSY;82 if (status & 2) /* PaperOut */83 ret |= PARPORT_STATUS_PAPEROUT;84 if (status & 4) /* Selected */85 ret |= PARPORT_STATUS_SELECT;86 /* the rest is not connected or handled autonomously in hardware */87 88 return ret;89}90 91static unsigned char amiga_read_status(struct parport *p)92{93 unsigned char status;94 95 status = status_amiga_to_pc(ciab.pra & 7);96 pr_debug("read_status %02x\n", status);97 return status;98}99 100static void amiga_enable_irq(struct parport *p)101{102 enable_irq(IRQ_AMIGA_CIAA_FLG);103}104 105static void amiga_disable_irq(struct parport *p)106{107 disable_irq(IRQ_AMIGA_CIAA_FLG);108}109 110static void amiga_data_forward(struct parport *p)111{112 pr_debug("forward\n");113 ciaa.ddrb = 0xff; /* all pins output */114 mb();115}116 117static void amiga_data_reverse(struct parport *p)118{119 pr_debug("reverse\n");120 ciaa.ddrb = 0; /* all pins input */121 mb();122}123 124static void amiga_init_state(struct pardevice *dev, struct parport_state *s)125{126 s->u.amiga.data = 0;127 s->u.amiga.datadir = 255;128 s->u.amiga.status = 0;129 s->u.amiga.statusdir = 0;130}131 132static void amiga_save_state(struct parport *p, struct parport_state *s)133{134 mb();135 s->u.amiga.data = ciaa.prb;136 s->u.amiga.datadir = ciaa.ddrb;137 s->u.amiga.status = ciab.pra & 7;138 s->u.amiga.statusdir = ciab.ddra & 7;139 mb();140}141 142static void amiga_restore_state(struct parport *p, struct parport_state *s)143{144 mb();145 ciaa.prb = s->u.amiga.data;146 ciaa.ddrb = s->u.amiga.datadir;147 ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status;148 ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir;149 mb();150}151 152static struct parport_operations pp_amiga_ops = {153 .write_data = amiga_write_data,154 .read_data = amiga_read_data,155 156 .write_control = amiga_write_control,157 .read_control = amiga_read_control,158 .frob_control = amiga_frob_control,159 160 .read_status = amiga_read_status,161 162 .enable_irq = amiga_enable_irq,163 .disable_irq = amiga_disable_irq,164 165 .data_forward = amiga_data_forward,166 .data_reverse = amiga_data_reverse,167 168 .init_state = amiga_init_state,169 .save_state = amiga_save_state,170 .restore_state = amiga_restore_state,171 172 .epp_write_data = parport_ieee1284_epp_write_data,173 .epp_read_data = parport_ieee1284_epp_read_data,174 .epp_write_addr = parport_ieee1284_epp_write_addr,175 .epp_read_addr = parport_ieee1284_epp_read_addr,176 177 .ecp_write_data = parport_ieee1284_ecp_write_data,178 .ecp_read_data = parport_ieee1284_ecp_read_data,179 .ecp_write_addr = parport_ieee1284_ecp_write_addr,180 181 .compat_write_data = parport_ieee1284_write_compat,182 .nibble_read_data = parport_ieee1284_read_nibble,183 .byte_read_data = parport_ieee1284_read_byte,184 185 .owner = THIS_MODULE,186};187 188/* ----------- Initialisation code --------------------------------- */189 190static int __init amiga_parallel_probe(struct platform_device *pdev)191{192 struct parport *p;193 int err;194 195 ciaa.ddrb = 0xff;196 ciab.ddra &= 0xf8;197 mb();198 199 p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG,200 PARPORT_DMA_NONE, &pp_amiga_ops);201 if (!p)202 return -EBUSY;203 204 err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name,205 p);206 if (err)207 goto out_irq;208 209 pr_info("%s: Amiga built-in port using irq\n", p->name);210 /* XXX: set operating mode */211 parport_announce_port(p);212 213 platform_set_drvdata(pdev, p);214 215 return 0;216 217out_irq:218 parport_put_port(p);219 return err;220}221 222static void __exit amiga_parallel_remove(struct platform_device *pdev)223{224 struct parport *port = platform_get_drvdata(pdev);225 226 parport_remove_port(port);227 if (port->irq != PARPORT_IRQ_NONE)228 free_irq(IRQ_AMIGA_CIAA_FLG, port);229 parport_put_port(port);230}231 232/*233 * amiga_parallel_remove() lives in .exit.text. For drivers registered via234 * module_platform_driver_probe() this is ok because they cannot get unbound at235 * runtime. So mark the driver struct with __refdata to prevent modpost236 * triggering a section mismatch warning.237 */238static struct platform_driver amiga_parallel_driver __refdata = {239 .remove_new = __exit_p(amiga_parallel_remove),240 .driver = {241 .name = "amiga-parallel",242 },243};244 245module_platform_driver_probe(amiga_parallel_driver, amiga_parallel_probe);246 247MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>");248MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port");249MODULE_LICENSE("GPL");250MODULE_ALIAS("platform:amiga-parallel");251