target/linux/coldfire/patches/088-m547x_8x_i2c_timeout_fix.patch

   1 From b9607c9083b767eac26df1d39a030f3cba5d3ae3 Mon Sep 17 00:00:00 2001
   2 From: Kurt Mahan <kmahan@freescale.com>
   3 Date: Fri, 18 Jul 2008 12:40:04 -0600
   4 Subject: [PATCH] Increase timeouts on I2C bus.
   5
   6 LTIBName: m547x-8x-i2c-timeout-fix
   7 Signed-off-by: Shrek Wu <b16972@freescale.com>
   8 ---
   9  drivers/i2c/busses/i2c-mcf548x.c |   40 +++++++++++++++++++++++++++++--------
  10  1 files changed, 31 insertions(+), 9 deletions(-)
  11
  12 --- a/drivers/i2c/busses/i2c-mcf548x.c
  13 +++ b/drivers/i2c/busses/i2c-mcf548x.c
  14 @@ -43,8 +43,8 @@ static struct i2c_adapter i2c_mcf_board_
  15         .id = I2C_HW_MPC107,
  16         .algo_data = &i2c_mcf_board_data,
  17         .class = I2C_CLASS_HWMON,
  18 -       .timeout = 1,
  19 -       .retries = 1
  20 +       .timeout = 100,
  21 +       .retries = 2
  22  };
  23  /*
  24   *  static void i2c_start()
  25 @@ -105,7 +105,7 @@ wait_for_bb(
  26         for (i = 0; i < adap->timeout; i++) {
  27                 if (!(MCF_I2SR & MCF_I2SR_IBB))
  28                         return 0;
  29 -               udelay(10);
  30 +               udelay(100);
  31         }
  32         printk(KERN_ERR "%s: timeout", __FUNCTION__);
  33         return -ETIMEDOUT;
  34 @@ -124,7 +124,7 @@ wait_for_not_bb(
  35         for (i = 0; i < adap->timeout; i++) {
  36                 if (MCF_I2SR & MCF_I2SR_IBB)
  37                         return 0;
  38 -               udelay(10);
  39 +               udelay(100);
  40         }
  41         printk(KERN_ERR "%s: timeout", __FUNCTION__);
  42         return -ETIMEDOUT;
  43 @@ -146,7 +146,7 @@ wait_xfer_done(
  44                         MCF_I2SR &= ~MCF_I2SR_IIF;
  45                         return 0;
  46                 }
  47 -               udelay(1);
  48 +               udelay(10);
  49         }
  50         printk(KERN_ERR "%s: timeout", __FUNCTION__);
  51         return -ETIMEDOUT;
  52 @@ -166,7 +166,7 @@ i2c_set_addr(
  53  ) {
  54         unsigned short flags = msg->flags;
  55         unsigned char addr;
  56 -
  57 +       MCF_I2CR |= MCF_I2CR_MTX;
  58         if ((flags & I2C_M_TEN)) {
  59                 /* 10 bit address not supported yet */
  60                 return -EIO;
  61 @@ -269,7 +269,7 @@ mcf_sendbytes(
  62                 i2c_stop(adap);
  63                 wait_for_bb(adap);
  64         } else {
  65 -               i2c_repstart(adap);
  66 +       /*      i2c_repstart(adap);*/
  67         }
  68
  69         return (i);
  70 @@ -330,7 +330,7 @@ mcf_readbytes(
  71                 i2c_stop(adap);
  72                 wait_for_bb(adap);
  73         } else {
  74 -               i2c_repstart(adap);
  75 +       /*      i2c_repstart(adap);*/
  76         }
  77
  78         return (i+1);
  79 @@ -380,6 +380,27 @@ mcf_xfer(
  80         wait_for_bb(adap);
  81
  82         for (i = 0; ret >= 0 && i < num; i++) {
  83 +               if (MCF_I2SR & MCF_I2SR_IBB) {
  84 +                       MCF_I2ICR = 0x00;
  85 +                       MCF_I2CR  = 0x00;
  86 +                       MCF_I2CR  = 0x0A;
  87 +                       timeout = MCF_I2DR;
  88 +                       MCF_I2SR  = 0x00;
  89 +                       MCF_I2CR  = 0x00;
  90 +                       MCF_I2ICR = 0x01;
  91 +               }
  92 +               /* setup SCL clock */
  93 +               MCF_I2FDR = get_clock(adap);
  94 +               /* set slave address */
  95 +               MCF_I2AR = get_own(adap);
  96 +               /* enable I2C module */
  97 +               MCF_I2CR = MCF_I2CR_IEN;
  98 +
  99 +               MCF_I2CR |= MCF_I2CR_TXAK;
 100 +
 101 +               /* Check for bus busy */
 102 +               wait_for_bb(adap);
 103 +
 104                 pmsg = &msgs[i];
 105
 106                 printk(KERN_DEBUG "i2c-algo-mcf: Doing %s %d bytes "
 107 @@ -388,7 +409,7 @@ mcf_xfer(
 108                         pmsg->len, pmsg->addr, i + 1, num);
 109
 110                 /* Send START */
 111 -               if (i == 0)
 112 +               /*if (i == 0)*/
 113                         i2c_start(adap);
 114
 115                 /* Wait for Bus Busy */
 116 @@ -440,6 +461,7 @@ mcf_xfer(
 117                                         "%d bytes.\n", ret);
 118                         }
 119                 }
 120 +       MCF_I2CR = 0;
 121         }
 122
 123         /* Disable I2C module */