drivers/media/pci/cx23885/cx23885-f300.c

   1 /*
   2  * Driver for Silicon Labs C8051F300 microcontroller.
   3  *
   4  * It is used for LNB power control in TeVii S470,
   5  * TBS 6920 PCIe DVB-S2 cards.
   6  *
   7  * Microcontroller connected to cx23885 GPIO pins:
   8  * GPIO0 - data         - P0.3 F300
   9  * GPIO1 - reset        - P0.2 F300
  10  * GPIO2 - clk          - P0.1 F300
  11  * GPIO3 - busy         - P0.0 F300
  12  *
  13  * Copyright (C) 2009 Igor M. Liplianin <liplianin@me.by>
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or
  18  * (at your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful,
  21  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  23  *
  24  * GNU General Public License for more details.
  25  */
  26
  27 #include "cx23885.h"
  28 #include "cx23885-f300.h"
  29
  30 #define F300_DATA       GPIO_0
  31 #define F300_RESET      GPIO_1
  32 #define F300_CLK        GPIO_2
  33 #define F300_BUSY       GPIO_3
  34
  35 static void f300_set_line(struct cx23885_dev *dev, u32 line, u8 lvl)
  36 {
  37         cx23885_gpio_enable(dev, line, 1);
  38         if (lvl == 1)
  39                 cx23885_gpio_set(dev, line);
  40         else
  41                 cx23885_gpio_clear(dev, line);
  42 }
  43
  44 static u8 f300_get_line(struct cx23885_dev *dev, u32 line)
  45 {
  46         cx23885_gpio_enable(dev, line, 0);
  47
  48         return cx23885_gpio_get(dev, line);
  49 }
  50
  51 static void f300_send_byte(struct cx23885_dev *dev, u8 dta)
  52 {
  53         u8 i;
  54
  55         for (i = 0; i < 8; i++) {
  56                 f300_set_line(dev, F300_CLK, 0);
  57                 udelay(30);
  58                 f300_set_line(dev, F300_DATA, (dta & 0x80) >> 7);/* msb first */
  59                 udelay(30);
  60                 dta <<= 1;
  61                 f300_set_line(dev, F300_CLK, 1);
  62                 udelay(30);
  63         }
  64 }
  65
  66 static u8 f300_get_byte(struct cx23885_dev *dev)
  67 {
  68         u8 i, dta = 0;
  69
  70         for (i = 0; i < 8; i++) {
  71                 f300_set_line(dev, F300_CLK, 0);
  72                 udelay(30);
  73                 dta <<= 1;
  74                 f300_set_line(dev, F300_CLK, 1);
  75                 udelay(30);
  76                 dta |= f300_get_line(dev, F300_DATA);/* msb first */
  77
  78         }
  79
  80         return dta;
  81 }
  82
  83 static u8 f300_xfer(struct dvb_frontend *fe, u8 *buf)
  84 {
  85         struct cx23885_tsport *port = fe->dvb->priv;
  86         struct cx23885_dev *dev = port->dev;
  87         u8 i, temp, ret = 0;
  88
  89         temp = buf[0];
  90         for (i = 0; i < buf[0]; i++)
  91                 temp += buf[i + 1];
  92         temp = (~temp + 1);/* get check sum */
  93         buf[1 + buf[0]] = temp;
  94
  95         f300_set_line(dev, F300_RESET, 1);
  96         f300_set_line(dev, F300_CLK, 1);
  97         udelay(30);
  98         f300_set_line(dev, F300_DATA, 1);
  99         msleep(1);
 100
 101         /* question: */
 102         f300_set_line(dev, F300_RESET, 0);/* begin to send data */
 103         msleep(1);
 104
 105         f300_send_byte(dev, 0xe0);/* the slave address is 0xe0, write */
 106         msleep(1);
 107
 108         temp = buf[0];
 109         temp += 2;
 110         for (i = 0; i < temp; i++)
 111                 f300_send_byte(dev, buf[i]);
 112
 113         f300_set_line(dev, F300_RESET, 1);/* sent data over */
 114         f300_set_line(dev, F300_DATA, 1);
 115
 116         /* answer: */
 117         temp = 0;
 118         for (i = 0; ((i < 8) & (temp == 0)); i++) {
 119                 msleep(1);
 120                 if (f300_get_line(dev, F300_BUSY) == 0)
 121                         temp = 1;
 122         }
 123
 124         if (i > 7) {
 125                 printk(KERN_ERR "%s: timeout, the slave no response\n",
 126                                                                 __func__);
 127                 ret = 1; /* timeout, the slave no response */
 128         } else { /* the slave not busy, prepare for getting data */
 129                 f300_set_line(dev, F300_RESET, 0);/*ready...*/
 130                 msleep(1);
 131                 f300_send_byte(dev, 0xe1);/* 0xe1 is Read */
 132                 msleep(1);
 133                 temp = f300_get_byte(dev);/*get the data length */
 134                 if (temp > 14)
 135                         temp = 14;
 136
 137                 for (i = 0; i < (temp + 1); i++)
 138                         f300_get_byte(dev);/* get data to empty buffer */
 139
 140                 f300_set_line(dev, F300_RESET, 1);/* received data over */
 141                 f300_set_line(dev, F300_DATA, 1);
 142         }
 143
 144         return ret;
 145 }
 146
 147 int f300_set_voltage(struct dvb_frontend *fe, enum fe_sec_voltage voltage)
 148 {
 149         u8 buf[16];
 150
 151         buf[0] = 0x05;
 152         buf[1] = 0x38;/* write port */
 153         buf[2] = 0x01;/* A port, lnb power */
 154
 155         switch (voltage) {
 156         case SEC_VOLTAGE_13:
 157                 buf[3] = 0x01;/* power on */
 158                 buf[4] = 0x02;/* B port, H/V */
 159                 buf[5] = 0x00;/*13V v*/
 160                 break;
 161         case SEC_VOLTAGE_18:
 162                 buf[3] = 0x01;
 163                 buf[4] = 0x02;
 164                 buf[5] = 0x01;/* 18V h*/
 165                 break;
 166         case SEC_VOLTAGE_OFF:
 167                 buf[3] = 0x00;/* power off */
 168                 buf[4] = 0x00;
 169                 buf[5] = 0x00;
 170                 break;
 171         }
 172
 173         return f300_xfer(fe, buf);
 174 }