drivers/media/dvb/mantis/mantis_uart.c

   1 /*
   2         Mantis PCI bridge driver
   3
   4         Copyright (C) Manu Abraham (abraham.manu@gmail.com)
   5
   6         This program is free software; you can redistribute it and/or modify
   7         it under the terms of the GNU General Public License as published by
   8         the Free Software Foundation; either version 2 of the License, or
   9         (at your option) any later version.
  10
  11         This program is distributed in the hope that it will be useful,
  12         but WITHOUT ANY WARRANTY; without even the implied warranty of
  13         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14         GNU General Public License for more details.
  15
  16         You should have received a copy of the GNU General Public License
  17         along with this program; if not, write to the Free Software
  18         Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/spinlock.h>
  23
  24 #include <linux/signal.h>
  25 #include <linux/sched.h>
  26 #include <linux/interrupt.h>
  27
  28 #include "dmxdev.h"
  29 #include "dvbdev.h"
  30 #include "dvb_demux.h"
  31 #include "dvb_frontend.h"
  32 #include "dvb_net.h"
  33
  34 #include "mantis_common.h"
  35 #include "mantis_reg.h"
  36 #include "mantis_uart.h"
  37
  38 struct mantis_uart_params {
  39         enum mantis_baud        baud_rate;
  40         enum mantis_parity      parity;
  41 };
  42
  43 static struct {
  44         char string[7];
  45 } rates[5] = {
  46         { "9600" },
  47         { "19200" },
  48         { "38400" },
  49         { "57600" },
  50         { "115200" }
  51 };
  52
  53 static struct {
  54         char string[5];
  55 } parity[3] = {
  56         { "NONE" },
  57         { "ODD" },
  58         { "EVEN" }
  59 };
  60
  61 #define UART_MAX_BUF                    16
  62
  63 int mantis_uart_read(struct mantis_pci *mantis, u8 *data)
  64 {
  65         struct mantis_hwconfig *config = mantis->hwconfig;
  66         u32 stat = 0, i;
  67
  68         /* get data */
  69         for (i = 0; i < (config->bytes + 1); i++) {
  70
  71                 stat = mmread(MANTIS_UART_STAT);
  72
  73                 if (stat & MANTIS_UART_RXFIFO_FULL) {
  74                         dprintk(MANTIS_ERROR, 1, "RX Fifo FULL");
  75                 }
  76                 data[i] = mmread(MANTIS_UART_RXD) & 0x3f;
  77
  78                 dprintk(MANTIS_DEBUG, 1, "Reading ... <%02x>", data[i] & 0x3f);
  79
  80                 if (data[i] & (1 << 7)) {
  81                         dprintk(MANTIS_ERROR, 1, "UART framing error");
  82                         return -EINVAL;
  83                 }
  84                 if (data[i] & (1 << 6)) {
  85                         dprintk(MANTIS_ERROR, 1, "UART parity error");
  86                         return -EINVAL;
  87                 }
  88         }
  89
  90         return 0;
  91 }
  92
  93 static void mantis_uart_work(struct work_struct *work)
  94 {
  95         struct mantis_pci *mantis = container_of(work, struct mantis_pci, uart_work);
  96         struct mantis_hwconfig *config = mantis->hwconfig;
  97         u8 buf[16];
  98         int i;
  99
 100         mantis_uart_read(mantis, buf);
 101
 102         for (i = 0; i < (config->bytes + 1); i++)
 103                 dprintk(MANTIS_INFO, 1, "UART BUF:%d <%02x> ", i, buf[i]);
 104
 105         dprintk(MANTIS_DEBUG, 0, "\n");
 106 }
 107
 108 static int mantis_uart_setup(struct mantis_pci *mantis,
 109                              struct mantis_uart_params *params)
 110 {
 111         u32 reg;
 112
 113         mmwrite((mmread(MANTIS_UART_CTL) | (params->parity & 0x3)), MANTIS_UART_CTL);
 114
 115         reg = mmread(MANTIS_UART_BAUD);
 116
 117         switch (params->baud_rate) {
 118         case MANTIS_BAUD_9600:
 119                 reg |= 0xd8;
 120                 break;
 121         case MANTIS_BAUD_19200:
 122                 reg |= 0x6c;
 123                 break;
 124         case MANTIS_BAUD_38400:
 125                 reg |= 0x36;
 126                 break;
 127         case MANTIS_BAUD_57600:
 128                 reg |= 0x23;
 129                 break;
 130         case MANTIS_BAUD_115200:
 131                 reg |= 0x11;
 132                 break;
 133         default:
 134                 return -EINVAL;
 135         }
 136
 137         mmwrite(reg, MANTIS_UART_BAUD);
 138
 139         return 0;
 140 }
 141
 142 int mantis_uart_init(struct mantis_pci *mantis)
 143 {
 144         struct mantis_hwconfig *config = mantis->hwconfig;
 145         struct mantis_uart_params params;
 146
 147         /* default parity: */
 148         params.baud_rate = config->baud_rate;
 149         params.parity = config->parity;
 150         dprintk(MANTIS_INFO, 1, "Initializing UART @ %sbps parity:%s",
 151                 rates[params.baud_rate].string,
 152                 parity[params.parity].string);
 153
 154         init_waitqueue_head(&mantis->uart_wq);
 155         spin_lock_init(&mantis->uart_lock);
 156
 157         INIT_WORK(&mantis->uart_work, mantis_uart_work);
 158
 159         /* disable interrupt */
 160         mmwrite(mmread(MANTIS_UART_CTL) & 0xffef, MANTIS_UART_CTL);
 161
 162         mantis_uart_setup(mantis, &params);
 163
 164         /* default 1 byte */
 165         mmwrite((mmread(MANTIS_UART_BAUD) | (config->bytes << 8)), MANTIS_UART_BAUD);
 166
 167         /* flush buffer */
 168         mmwrite((mmread(MANTIS_UART_CTL) | MANTIS_UART_RXFLUSH), MANTIS_UART_CTL);
 169
 170         /* enable interrupt */
 171         mmwrite(mmread(MANTIS_INT_MASK) | 0x800, MANTIS_INT_MASK);
 172         mmwrite(mmread(MANTIS_UART_CTL) | MANTIS_UART_RXINT, MANTIS_UART_CTL);
 173
 174         schedule_work(&mantis->uart_work);
 175         dprintk(MANTIS_DEBUG, 1, "UART successfully initialized");
 176
 177         return 0;
 178 }
 179 EXPORT_SYMBOL_GPL(mantis_uart_init);
 180
 181 void mantis_uart_exit(struct mantis_pci *mantis)
 182 {
 183         /* disable interrupt */
 184         mmwrite(mmread(MANTIS_UART_CTL) & 0xffef, MANTIS_UART_CTL);
 185         flush_work_sync(&mantis->uart_work);
 186 }
 187 EXPORT_SYMBOL_GPL(mantis_uart_exit);