1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Low-level parallel port routines for the Amiga built-in port 3 * 4 * Author: Joerg Dorchain <joerg@dorchain.net> 5 * 6 * This is a complete rewrite of the code, but based heaviy upon the old 7 * lp_intern. code. 8 * 9 * The built-in Amiga parallel port provides one port at a fixed address 10 * with 8 bidirectional data lines (D0 - D7) and 3 bidirectional status 11 * lines (BUSY, POUT, SEL), 1 output control line /STROBE (raised automatically 12 * in hardware when the data register is accessed), and 1 input control line 13 * /ACK, able to cause an interrupt, but both not directly settable by 14 * 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 DEBUG 31 #ifdef DEBUG 32 #define DPRINTK printk 33 #else 34 #define DPRINTK(x...) do { } while (0) 35 #endif 36 37 38 static void amiga_write_data(struct parport *p, unsigned char data) 39 { 40 DPRINTK(KERN_DEBUG "write_data %c\n",data); 41 /* Triggers also /STROBE. This behavior cannot be changed */ 42 ciaa.prb = data; 43 mb(); 44 } 45 46 static unsigned char amiga_read_data(struct parport *p) 47 { 48 /* Triggers also /STROBE. This behavior cannot be changed */ 49 return ciaa.prb; 50 } 51 52 static unsigned char control_amiga_to_pc(unsigned char control) 53 { 54 return PARPORT_CONTROL_SELECT | 55 PARPORT_CONTROL_AUTOFD | PARPORT_CONTROL_STROBE; 56 /* fake value: interrupt enable, select in, no reset, 57 no autolf, no strobe - seems to be closest the wiring diagram */ 58 } 59 60 static void amiga_write_control(struct parport *p, unsigned char control) 61 { 62 DPRINTK(KERN_DEBUG "write_control %02x\n",control); 63 /* No implementation possible */ 64 } 65 66 static unsigned char amiga_read_control( struct parport *p) 67 { 68 DPRINTK(KERN_DEBUG "read_control \n"); 69 return control_amiga_to_pc(0); 70 } 71 72 static unsigned char amiga_frob_control( struct parport *p, unsigned char mask, unsigned char val) 73 { 74 unsigned char old; 75 76 DPRINTK(KERN_DEBUG "frob_control mask %02x, value %02x\n",mask,val); 77 old = amiga_read_control(p); 78 amiga_write_control(p, (old & ~mask) ^ val); 79 return old; 80 } 81 82 static unsigned char status_amiga_to_pc(unsigned char status) 83 { 84 unsigned char ret = PARPORT_STATUS_BUSY | PARPORT_STATUS_ACK | PARPORT_STATUS_ERROR; 85 86 if (status & 1) /* Busy */ 87 ret &= ~PARPORT_STATUS_BUSY; 88 if (status & 2) /* PaperOut */ 89 ret |= PARPORT_STATUS_PAPEROUT; 90 if (status & 4) /* Selected */ 91 ret |= PARPORT_STATUS_SELECT; 92 /* the rest is not connected or handled autonomously in hardware */ 93 94 return ret; 95 } 96 97 static unsigned char amiga_read_status(struct parport *p) 98 { 99 unsigned char status; 100 101 status = status_amiga_to_pc(ciab.pra & 7); 102 DPRINTK(KERN_DEBUG "read_status %02x\n", status); 103 return status; 104 } 105 106 static void amiga_enable_irq(struct parport *p) 107 { 108 enable_irq(IRQ_AMIGA_CIAA_FLG); 109 } 110 111 static void amiga_disable_irq(struct parport *p) 112 { 113 disable_irq(IRQ_AMIGA_CIAA_FLG); 114 } 115 116 static void amiga_data_forward(struct parport *p) 117 { 118 DPRINTK(KERN_DEBUG "forward\n"); 119 ciaa.ddrb = 0xff; /* all pins output */ 120 mb(); 121 } 122 123 static void amiga_data_reverse(struct parport *p) 124 { 125 DPRINTK(KERN_DEBUG "reverse\n"); 126 ciaa.ddrb = 0; /* all pins input */ 127 mb(); 128 } 129 130 static void amiga_init_state(struct pardevice *dev, struct parport_state *s) 131 { 132 s->u.amiga.data = 0; 133 s->u.amiga.datadir = 255; 134 s->u.amiga.status = 0; 135 s->u.amiga.statusdir = 0; 136 } 137 138 static void amiga_save_state(struct parport *p, struct parport_state *s) 139 { 140 mb(); 141 s->u.amiga.data = ciaa.prb; 142 s->u.amiga.datadir = ciaa.ddrb; 143 s->u.amiga.status = ciab.pra & 7; 144 s->u.amiga.statusdir = ciab.ddra & 7; 145 mb(); 146 } 147 148 static void amiga_restore_state(struct parport *p, struct parport_state *s) 149 { 150 mb(); 151 ciaa.prb = s->u.amiga.data; 152 ciaa.ddrb = s->u.amiga.datadir; 153 ciab.pra |= (ciab.pra & 0xf8) | s->u.amiga.status; 154 ciab.ddra |= (ciab.ddra & 0xf8) | s->u.amiga.statusdir; 155 mb(); 156 } 157 158 static struct parport_operations pp_amiga_ops = { 159 .write_data = amiga_write_data, 160 .read_data = amiga_read_data, 161 162 .write_control = amiga_write_control, 163 .read_control = amiga_read_control, 164 .frob_control = amiga_frob_control, 165 166 .read_status = amiga_read_status, 167 168 .enable_irq = amiga_enable_irq, 169 .disable_irq = amiga_disable_irq, 170 171 .data_forward = amiga_data_forward, 172 .data_reverse = amiga_data_reverse, 173 174 .init_state = amiga_init_state, 175 .save_state = amiga_save_state, 176 .restore_state = amiga_restore_state, 177 178 .epp_write_data = parport_ieee1284_epp_write_data, 179 .epp_read_data = parport_ieee1284_epp_read_data, 180 .epp_write_addr = parport_ieee1284_epp_write_addr, 181 .epp_read_addr = parport_ieee1284_epp_read_addr, 182 183 .ecp_write_data = parport_ieee1284_ecp_write_data, 184 .ecp_read_data = parport_ieee1284_ecp_read_data, 185 .ecp_write_addr = parport_ieee1284_ecp_write_addr, 186 187 .compat_write_data = parport_ieee1284_write_compat, 188 .nibble_read_data = parport_ieee1284_read_nibble, 189 .byte_read_data = parport_ieee1284_read_byte, 190 191 .owner = THIS_MODULE, 192 }; 193 194 /* ----------- Initialisation code --------------------------------- */ 195 196 static int __init amiga_parallel_probe(struct platform_device *pdev) 197 { 198 struct parport *p; 199 int err; 200 201 ciaa.ddrb = 0xff; 202 ciab.ddra &= 0xf8; 203 mb(); 204 205 p = parport_register_port((unsigned long)&ciaa.prb, IRQ_AMIGA_CIAA_FLG, 206 PARPORT_DMA_NONE, &pp_amiga_ops); 207 if (!p) 208 return -EBUSY; 209 210 err = request_irq(IRQ_AMIGA_CIAA_FLG, parport_irq_handler, 0, p->name, 211 p); 212 if (err) 213 goto out_irq; 214 215 printk(KERN_INFO "%s: Amiga built-in port using irq\n", p->name); 216 /* XXX: set operating mode */ 217 parport_announce_port(p); 218 219 platform_set_drvdata(pdev, p); 220 221 return 0; 222 223 out_irq: 224 parport_put_port(p); 225 return err; 226 } 227 228 static int __exit amiga_parallel_remove(struct platform_device *pdev) 229 { 230 struct parport *port = platform_get_drvdata(pdev); 231 232 parport_remove_port(port); 233 if (port->irq != PARPORT_IRQ_NONE) 234 free_irq(IRQ_AMIGA_CIAA_FLG, port); 235 parport_put_port(port); 236 return 0; 237 } 238 239 static struct platform_driver amiga_parallel_driver = { 240 .remove = __exit_p(amiga_parallel_remove), 241 .driver = { 242 .name = "amiga-parallel", 243 }, 244 }; 245 246 module_platform_driver_probe(amiga_parallel_driver, amiga_parallel_probe); 247 248 MODULE_AUTHOR("Joerg Dorchain <joerg@dorchain.net>"); 249 MODULE_DESCRIPTION("Parport Driver for Amiga builtin Port"); 250 MODULE_SUPPORTED_DEVICE("Amiga builtin Parallel Port"); 251 MODULE_LICENSE("GPL"); 252 MODULE_ALIAS("platform:amiga-parallel"); 253