LXR linux/drivers/media/pci/mantis/mantis

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3        Mantis PCI bridge driver
   4
   5        Copyright (C) Manu Abraham (abraham.manu@gmail.com)
   6
   7*/
   8
   9#include <linux/kernel.h>
  10#include <linux/spinlock.h>
  11#include <asm/io.h>
  12
  13#include <linux/signal.h>
  14#include <linux/sched.h>
  15#include <linux/interrupt.h>
  16#include <linux/pci.h>
  17
  18#include <media/dmxdev.h>
  19#include <media/dvbdev.h>
  20#include <media/dvb_demux.h>
  21#include <media/dvb_frontend.h>
  22#include <media/dvb_net.h>
  23
  24#include "mantis_common.h"
  25#include "mantis_reg.h"
  26#include "mantis_uart.h"
  27#include "mantis_input.h"
  28
  29struct mantis_uart_params {
  30        enum mantis_baud        baud_rate;
  31        enum mantis_parity      parity;
  32};
  33
  34static struct {
  35        char string[7];
  36} rates[5] = {
  37        { "9600" },
  38        { "19200" },
  39        { "38400" },
  40        { "57600" },
  41        { "115200" }
  42};
  43
  44static struct {
  45        char string[5];
  46} parity[3] = {
  47        { "NONE" },
  48        { "ODD" },
  49        { "EVEN" }
  50};
  51
  52static void mantis_uart_read(struct mantis_pci *mantis)
  53{
  54        struct mantis_hwconfig *config = mantis->hwconfig;
  55        int i, scancode = 0, err = 0;
  56
  57        /* get data */
  58        dprintk(MANTIS_DEBUG, 1, "UART Reading ...");
  59        for (i = 0; i < (config->bytes + 1); i++) {
  60                int data = mmread(MANTIS_UART_RXD);
  61
  62                dprintk(MANTIS_DEBUG, 0, " <%02x>", data);
  63
  64                scancode = (scancode << 8) | (data & 0x3f);
  65                err |= data;
  66
  67                if (data & (1 << 7))
  68                        dprintk(MANTIS_ERROR, 1, "UART framing error");
  69
  70                if (data & (1 << 6))
  71                        dprintk(MANTIS_ERROR, 1, "UART parity error");
  72        }
  73        dprintk(MANTIS_DEBUG, 0, "\n");
  74
  75        if ((err & 0xC0) == 0)
  76                mantis_input_process(mantis, scancode);
  77}
  78
  79static void mantis_uart_work(struct work_struct *work)
  80{
  81        struct mantis_pci *mantis = container_of(work, struct mantis_pci, uart_work);
  82        u32 stat;
  83        unsigned long timeout;
  84
  85        stat = mmread(MANTIS_UART_STAT);
  86
  87        if (stat & MANTIS_UART_RXFIFO_FULL)
  88                dprintk(MANTIS_ERROR, 1, "RX Fifo FULL");
  89
  90        /*
  91         * MANTIS_UART_RXFIFO_DATA is only set if at least
  92         * config->bytes + 1 bytes are in the FIFO.
  93         */
  94
  95        /* FIXME: is 10ms good enough ? */
  96        timeout = jiffies +  msecs_to_jiffies(10);
  97        while (stat & MANTIS_UART_RXFIFO_DATA) {
  98                mantis_uart_read(mantis);
  99                stat = mmread(MANTIS_UART_STAT);
 100
 101                if (!time_is_after_jiffies(timeout))
 102                        break;
 103        }
 104
 105        /* re-enable UART (RX) interrupt */
 106        mantis_unmask_ints(mantis, MANTIS_INT_IRQ1);
 107}
 108
 109static int mantis_uart_setup(struct mantis_pci *mantis,
 110                             struct mantis_uart_params *params)
 111{
 112        u32 reg;
 113
 114        mmwrite((mmread(MANTIS_UART_CTL) | (params->parity & 0x3)), MANTIS_UART_CTL);
 115
 116        reg = mmread(MANTIS_UART_BAUD);
 117
 118        switch (params->baud_rate) {
 119        case MANTIS_BAUD_9600:
 120                reg |= 0xd8;
 121                break;
 122        case MANTIS_BAUD_19200:
 123                reg |= 0x6c;
 124                break;
 125        case MANTIS_BAUD_38400:
 126                reg |= 0x36;
 127                break;
 128        case MANTIS_BAUD_57600:
 129                reg |= 0x23;
 130                break;
 131        case MANTIS_BAUD_115200:
 132                reg |= 0x11;
 133                break;
 134        default:
 135                return -EINVAL;
 136        }
 137
 138        mmwrite(reg, MANTIS_UART_BAUD);
 139
 140        return 0;
 141}
 142
 143int mantis_uart_init(struct mantis_pci *mantis)
 144{
 145        struct mantis_hwconfig *config = mantis->hwconfig;
 146        struct mantis_uart_params params;
 147
 148        /* default parity: */
 149        params.baud_rate = config->baud_rate;
 150        params.parity = config->parity;
 151        dprintk(MANTIS_INFO, 1, "Initializing UART @ %sbps parity:%s",
 152                rates[params.baud_rate].string,
 153                parity[params.parity].string);
 154
 155        INIT_WORK(&mantis->uart_work, mantis_uart_work);
 156
 157        /* disable interrupt */
 158        mmwrite(mmread(MANTIS_UART_CTL) & 0xffef, MANTIS_UART_CTL);
 159
 160        mantis_uart_setup(mantis, &params);
 161
 162        /* default 1 byte */
 163        mmwrite((mmread(MANTIS_UART_BAUD) | (config->bytes << 8)), MANTIS_UART_BAUD);
 164
 165        /* flush buffer */
 166        mmwrite((mmread(MANTIS_UART_CTL) | MANTIS_UART_RXFLUSH), MANTIS_UART_CTL);
 167
 168        /* enable interrupt */
 169        mmwrite(mmread(MANTIS_UART_CTL) | MANTIS_UART_RXINT, MANTIS_UART_CTL);
 170        mantis_unmask_ints(mantis, MANTIS_INT_IRQ1);
 171
 172        schedule_work(&mantis->uart_work);
 173        dprintk(MANTIS_DEBUG, 1, "UART successfully initialized");
 174
 175        return 0;
 176}
 177EXPORT_SYMBOL_GPL(mantis_uart_init);
 178
 179void mantis_uart_exit(struct mantis_pci *mantis)
 180{
 181        /* disable interrupt */
 182        mantis_mask_ints(mantis, MANTIS_INT_IRQ1);
 183        mmwrite(mmread(MANTIS_UART_CTL) & 0xffef, MANTIS_UART_CTL);
 184        flush_work(&mantis->uart_work);
 185}
 186EXPORT_SYMBOL_GPL(mantis_uart_exit);
 187