drivers/media/dvb/frontends/dibx000_common.c

   1 #include <linux/i2c.h>
   2
   3 #include "dibx000_common.h"
   4
   5 static int debug;
   6 module_param(debug, int, 0644);
   7 MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");
   8
   9 #define dprintk(args...) do { if (debug) { printk(KERN_DEBUG "DiBX000: "); printk(args); } } while (0)
  10
  11 static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
  12 {
  13         u8 b[4] = {
  14                 (reg >> 8) & 0xff, reg & 0xff,
  15                 (val >> 8) & 0xff, val & 0xff,
  16         };
  17         struct i2c_msg msg = {
  18                 .addr = mst->i2c_addr,.flags = 0,.buf = b,.len = 4
  19         };
  20         return i2c_transfer(mst->i2c_adap, &msg, 1) != 1 ? -EREMOTEIO : 0;
  21 }
  22
  23
  24 static int dibx000_i2c_select_interface(struct dibx000_i2c_master *mst,
  25                                         enum dibx000_i2c_interface intf)
  26 {
  27         if (mst->device_rev > DIB3000MC && mst->selected_interface != intf) {
  28                 dprintk("selecting interface: %d\n", intf);
  29                 mst->selected_interface = intf;
  30                 return dibx000_write_word(mst, mst->base_reg + 4, intf);
  31         }
  32         return 0;
  33 }
  34
  35 static int dibx000_i2c_gate_ctrl(struct dibx000_i2c_master *mst, u8 tx[4],
  36                                  u8 addr, int onoff)
  37 {
  38         u16 val;
  39
  40
  41         if (onoff)
  42                 val = addr << 8;        // bit 7 = use master or not, if 0, the gate is open
  43         else
  44                 val = 1 << 7;
  45
  46         if (mst->device_rev > DIB7000)
  47                 val <<= 1;
  48
  49         tx[0] = (((mst->base_reg + 1) >> 8) & 0xff);
  50         tx[1] = ((mst->base_reg + 1) & 0xff);
  51         tx[2] = val >> 8;
  52         tx[3] = val & 0xff;
  53
  54         return 0;
  55 }
  56
  57 static u32 dibx000_i2c_func(struct i2c_adapter *adapter)
  58 {
  59         return I2C_FUNC_I2C;
  60 }
  61
  62 static int dibx000_i2c_gated_tuner_xfer(struct i2c_adapter *i2c_adap,
  63                                         struct i2c_msg msg[], int num)
  64 {
  65         struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
  66         struct i2c_msg m[2 + num];
  67         u8 tx_open[4], tx_close[4];
  68
  69         memset(m, 0, sizeof(struct i2c_msg) * (2 + num));
  70
  71         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
  72
  73         dibx000_i2c_gate_ctrl(mst, tx_open, msg[0].addr, 1);
  74         m[0].addr = mst->i2c_addr;
  75         m[0].buf = tx_open;
  76         m[0].len = 4;
  77
  78         memcpy(&m[1], msg, sizeof(struct i2c_msg) * num);
  79
  80         dibx000_i2c_gate_ctrl(mst, tx_close, 0, 0);
  81         m[num + 1].addr = mst->i2c_addr;
  82         m[num + 1].buf = tx_close;
  83         m[num + 1].len = 4;
  84
  85         return i2c_transfer(mst->i2c_adap, m, 2 + num) == 2 + num ? num : -EIO;
  86 }
  87
  88 static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {
  89         .master_xfer = dibx000_i2c_gated_tuner_xfer,
  90         .functionality = dibx000_i2c_func,
  91 };
  92
  93 struct i2c_adapter *dibx000_get_i2c_adapter(struct dibx000_i2c_master *mst,
  94                                             enum dibx000_i2c_interface intf,
  95                                             int gating)
  96 {
  97         struct i2c_adapter *i2c = NULL;
  98
  99         switch (intf) {
 100         case DIBX000_I2C_INTERFACE_TUNER:
 101                 if (gating)
 102                         i2c = &mst->gated_tuner_i2c_adap;
 103                 break;
 104         default:
 105                 printk(KERN_ERR "DiBX000: incorrect I2C interface selected\n");
 106                 break;
 107         }
 108
 109         return i2c;
 110 }
 111
 112 EXPORT_SYMBOL(dibx000_get_i2c_adapter);
 113
 114 void dibx000_reset_i2c_master(struct dibx000_i2c_master *mst)
 115 {
 116         /* initialize the i2c-master by closing the gate */
 117         u8 tx[4];
 118         struct i2c_msg m = {.addr = mst->i2c_addr,.buf = tx,.len = 4 };
 119
 120         dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
 121         i2c_transfer(mst->i2c_adap, &m, 1);
 122         mst->selected_interface = 0xff; // the first time force a select of the I2C
 123         dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
 124 }
 125
 126 EXPORT_SYMBOL(dibx000_reset_i2c_master);
 127
 128 static int i2c_adapter_init(struct i2c_adapter *i2c_adap,
 129                             struct i2c_algorithm *algo, const char *name,
 130                             struct dibx000_i2c_master *mst)
 131 {
 132         strncpy(i2c_adap->name, name, sizeof(i2c_adap->name));
 133         i2c_adap->class = I2C_CLASS_TV_DIGITAL, i2c_adap->algo = algo;
 134         i2c_adap->algo_data = NULL;
 135         i2c_set_adapdata(i2c_adap, mst);
 136         if (i2c_add_adapter(i2c_adap) < 0)
 137                 return -ENODEV;
 138         return 0;
 139 }
 140
 141 int dibx000_init_i2c_master(struct dibx000_i2c_master *mst, u16 device_rev,
 142                             struct i2c_adapter *i2c_adap, u8 i2c_addr)
 143 {
 144         u8 tx[4];
 145         struct i2c_msg m = {.addr = i2c_addr >> 1,.buf = tx,.len = 4 };
 146
 147         mst->device_rev = device_rev;
 148         mst->i2c_adap = i2c_adap;
 149         mst->i2c_addr = i2c_addr >> 1;
 150
 151         if (device_rev == DIB7000P || device_rev == DIB8000)
 152                 mst->base_reg = 1024;
 153         else
 154                 mst->base_reg = 768;
 155
 156         if (i2c_adapter_init
 157             (&mst->gated_tuner_i2c_adap, &dibx000_i2c_gated_tuner_algo,
 158              "DiBX000 tuner I2C bus", mst) != 0)
 159                 printk(KERN_ERR
 160                        "DiBX000: could not initialize the tuner i2c_adapter\n");
 161
 162         /* initialize the i2c-master by closing the gate */
 163         dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
 164
 165         return i2c_transfer(i2c_adap, &m, 1) == 1;
 166 }
 167
 168 EXPORT_SYMBOL(dibx000_init_i2c_master);
 169
 170 void dibx000_exit_i2c_master(struct dibx000_i2c_master *mst)
 171 {
 172         i2c_del_adapter(&mst->gated_tuner_i2c_adap);
 173 }
 174
 175 EXPORT_SYMBOL(dibx000_exit_i2c_master);
 176
 177 MODULE_AUTHOR("Patrick Boettcher <pboettcher@dibcom.fr>");
 178 MODULE_DESCRIPTION("Common function the DiBcom demodulator family");
 179 MODULE_LICENSE("GPL");