drivers/ata/pata_parport/comm.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * (c) 1997-1998  Grant R. Guenther <[email protected]>
   4  *
   5  * comm.c is a low-level protocol driver for some older models of the DataStor
   6  * "Commuter" parallel to IDE adapter. Some of the parallel port devices
   7  * marketed by Arista currently use this adapter.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/delay.h>
  13 #include <linux/kernel.h>
  14 #include <linux/types.h>
  15 #include <linux/wait.h>
  16 #include <asm/io.h>
  17 #include "pata_parport.h"
  18
  19 /*
  20  * mode codes:  0  nybble reads, 8-bit writes
  21  *              1  8-bit reads and writes
  22  *              2  8-bit EPP mode
  23  */
  24
  25 #define j44(a, b)       (((a >> 3) & 0x0f) | ((b << 1) & 0xf0))
  26
  27 #define P1      w2(5);w2(0xd);w2(0xd);w2(5);w2(4);
  28 #define P2      w2(5);w2(7);w2(7);w2(5);w2(4);
  29
  30 /*
  31  * cont = 0 - access the IDE register file
  32  * cont = 1 - access the IDE command set
  33  */
  34 static int  cont_map[2] = { 0x08, 0x10 };
  35
  36 static int comm_read_regr(struct pi_adapter *pi, int cont, int regr)
  37 {
  38         int l, h, r;
  39
  40         r = regr + cont_map[cont];
  41
  42         switch (pi->mode) {
  43         case 0:
  44                 w0(r); P1; w0(0);
  45                 w2(6); l = r1(); w0(0x80); h = r1(); w2(4);
  46                 return j44(l, h);
  47
  48         case 1:
  49                 w0(r+0x20); P1;
  50                 w0(0); w2(0x26); h = r0(); w2(4);
  51                 return h;
  52
  53         case 2:
  54         case 3:
  55         case 4:
  56                 w3(r+0x20); (void)r1();
  57                 w2(0x24); h = r4(); w2(4);
  58                 return h;
  59         }
  60
  61         return -1;
  62 }
  63
  64 static void comm_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
  65 {
  66         int r = regr + cont_map[cont];
  67
  68         switch (pi->mode) {
  69         case 0:
  70         case 1:
  71                 w0(r); P1; w0(val); P2;
  72                 break;
  73         case 2:
  74         case 3:
  75         case 4:
  76                 w3(r); (void)r1(); w4(val);
  77                 break;
  78         }
  79 }
  80
  81 static void comm_connect(struct pi_adapter *pi)
  82 {
  83         pi->saved_r0 = r0();
  84         pi->saved_r2 = r2();
  85         w2(4); w0(0xff); w2(6);
  86         w2(4); w0(0xaa); w2(6);
  87         w2(4); w0(0x00); w2(6);
  88         w2(4); w0(0x87); w2(6);
  89         w2(4); w0(0xe0); w2(0xc); w2(0xc); w2(4);
  90 }
  91
  92 static void comm_disconnect(struct pi_adapter *pi)
  93 {
  94         w2(0); w2(0); w2(0); w2(4);
  95         w0(pi->saved_r0);
  96         w2(pi->saved_r2);
  97 }
  98
  99 static void comm_read_block(struct pi_adapter *pi, char *buf, int count)
 100 {
 101         int i, l, h;
 102
 103         switch (pi->mode) {
 104         case 0:
 105                 w0(0x48); P1;
 106                 for (i = 0; i < count; i++) {
 107                         w0(0); w2(6); l = r1();
 108                         w0(0x80); h = r1(); w2(4);
 109                         buf[i] = j44(l, h);
 110                 }
 111                 break;
 112         case 1:
 113                 w0(0x68); P1; w0(0);
 114                 for (i = 0; i < count; i++) {
 115                         w2(0x26);
 116                         buf[i] = r0();
 117                         w2(0x24);
 118                 }
 119                 w2(4);
 120                 break;
 121         case 2:
 122                 w3(0x68); (void)r1(); w2(0x24);
 123                 for (i = 0; i < count; i++)
 124                         buf[i] = r4();
 125                 w2(4);
 126                 break;
 127         case 3:
 128                 w3(0x68); (void)r1(); w2(0x24);
 129                 for (i = 0; i < count / 2; i++)
 130                         ((u16 *)buf)[i] = r4w();
 131                 w2(4);
 132                 break;
 133         case 4:
 134                 w3(0x68); (void)r1(); w2(0x24);
 135                 for (i = 0; i < count / 4; i++)
 136                         ((u32 *)buf)[i] = r4l();
 137                 w2(4);
 138                 break;
 139         }
 140 }
 141
 142 /* NB: Watch out for the byte swapped writes ! */
 143 static void comm_write_block(struct pi_adapter *pi, char *buf, int count)
 144 {
 145         int k;
 146
 147         switch (pi->mode) {
 148         case 0:
 149         case 1:
 150                 w0(0x68); P1;
 151                 for (k = 0; k < count; k++) {
 152                         w2(5);
 153                         w0(buf[k ^ 1]);
 154                         w2(7);
 155                 }
 156                 w2(5); w2(4);
 157                 break;
 158         case 2:
 159                 w3(0x48); (void)r1();
 160                 for (k = 0; k < count; k++)
 161                         w4(buf[k ^ 1]);
 162                 break;
 163         case 3:
 164                 w3(0x48); (void)r1();
 165                 for (k = 0; k < count / 2; k++)
 166                         w4w(swab16(((u16 *)buf)[k]));
 167                 break;
 168         case 4:
 169                 w3(0x48); (void)r1();
 170                 for (k = 0; k < count / 4; k++)
 171                         w4l(swab16(((u16 *)buf)[2 * k]) |
 172                             swab16(((u16 *)buf)[2 * k + 1]) << 16);
 173                 break;
 174         }
 175 }
 176
 177 static void comm_log_adapter(struct pi_adapter *pi)
 178 {
 179         char *mode_string[5] = { "4-bit", "8-bit", "EPP-8", "EPP-16", "EPP-32" };
 180
 181         dev_info(&pi->dev,
 182                  "DataStor Commuter at 0x%x, mode %d (%s), delay %d\n",
 183                  pi->port, pi->mode, mode_string[pi->mode], pi->delay);
 184 }
 185
 186 static struct pi_protocol comm = {
 187         .owner          = THIS_MODULE,
 188         .name           = "comm",
 189         .max_mode       = 5,
 190         .epp_first      = 2,
 191         .default_delay  = 1,
 192         .max_units      = 1,
 193         .write_regr     = comm_write_regr,
 194         .read_regr      = comm_read_regr,
 195         .write_block    = comm_write_block,
 196         .read_block     = comm_read_block,
 197         .connect        = comm_connect,
 198         .disconnect     = comm_disconnect,
 199         .log_adapter    = comm_log_adapter,
 200 };
 201
 202 MODULE_LICENSE("GPL");
 203 MODULE_AUTHOR("Grant R. Guenther <[email protected]>");
 204 MODULE_DESCRIPTION("DataStor Commuter parallel port IDE adapter protocol driver");
 205 module_pata_parport_driver(comm);