target/linux/layerscape/patches-4.9/809-i2c-support-layerscape.patch

   1 From 3c5032fe34f1af50e9e5fe58d40bf93c1717302f Mon Sep 17 00:00:00 2001
   2 From: Yangbo Lu <yangbo.lu@nxp.com>
   3 Date: Mon, 25 Sep 2017 12:19:53 +0800
   4 Subject: [PATCH] i2c: support layerscape
   5
   6 This is a integrated patch for layerscape i2c support.
   7
   8 Signed-off-by: Zhang Ying-22455 <ying.zhang22455@nxp.com>
   9 Signed-off-by: Priyanka Jain <Priyanka.Jain@freescale.com>
  10 Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
  11 ---
  12  drivers/i2c/busses/i2c-imx.c        | 10 ++++++++-
  13  drivers/i2c/muxes/i2c-mux-pca954x.c | 43 +++++++++++++++++++++++++++++++++++++
  14  2 files changed, 52 insertions(+), 1 deletion(-)
  15
  16 --- a/drivers/i2c/busses/i2c-imx.c
  17 +++ b/drivers/i2c/busses/i2c-imx.c
  18 @@ -889,6 +889,14 @@ static int i2c_imx_xfer(struct i2c_adapt
  19
  20         dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
  21
  22 +       /*
  23 +        * workround for ERR010027: ensure that the I2C BUS is idle
  24 +        * before switching to master mode and attempting a Start cycle
  25 +        */
  26 +       result =  i2c_imx_bus_busy(i2c_imx, 0);
  27 +       if (result)
  28 +               goto out;
  29 +
  30         result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent);
  31         if (result < 0)
  32                 goto out;
  33 @@ -1100,7 +1108,7 @@ static int i2c_imx_probe(struct platform
  34         }
  35
  36         /* Request IRQ */
  37 -       ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
  38 +       ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, IRQF_SHARED,
  39                                 pdev->name, i2c_imx);
  40         if (ret) {
  41                 dev_err(&pdev->dev, "can't claim irq %d\n", irq);
  42 --- a/drivers/i2c/muxes/i2c-mux-pca954x.c
  43 +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
  44 @@ -74,6 +74,7 @@ struct pca954x {
  45         u8 last_chan;           /* last register value */
  46         u8 deselect;
  47         struct i2c_client *client;
  48 +       u8 disable_mux;         /* do not disable mux if val not 0 */
  49  };
  50
  51  /* Provide specs for the PCA954x types we know about */
  52 @@ -196,6 +197,13 @@ static int pca954x_deselect_mux(struct i
  53         if (!(data->deselect & (1 << chan)))
  54                 return 0;
  55
  56 +#ifdef CONFIG_ARCH_LAYERSCAPE
  57 +       if (data->disable_mux != 0)
  58 +               data->last_chan = data->chip->nchans;
  59 +       else
  60 +               data->last_chan = 0;
  61 +       return pca954x_reg_write(muxc->parent, client, data->disable_mux);
  62 +#endif
  63         /* Deselect active channel */
  64         data->last_chan = 0;
  65         return pca954x_reg_write(muxc->parent, client, data->last_chan);
  66 @@ -228,6 +236,28 @@ static int pca954x_probe(struct i2c_clie
  67                 return -ENOMEM;
  68         data = i2c_mux_priv(muxc);
  69
  70 +#ifdef CONFIG_ARCH_LAYERSCAPE
  71 +       /* The point here is that you must not disable a mux if there
  72 +        * are no pullups on the input or you mess up the I2C. This
  73 +        * needs to be put into the DTS really as the kernel cannot
  74 +        * know this otherwise.
  75 +        */
  76 +       match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
  77 +       if (match)
  78 +               data->chip = of_device_get_match_data(&client->dev);
  79 +       else
  80 +               data->chip = &chips[id->driver_data];
  81 +
  82 +       data->disable_mux = of_node &&
  83 +               of_property_read_bool(of_node, "i2c-mux-never-disable") &&
  84 +               data->chip->muxtype == pca954x_ismux ?
  85 +               data->chip->enable : 0;
  86 +       /* force the first selection */
  87 +       if (data->disable_mux != 0)
  88 +               data->last_chan = data->chip->nchans;
  89 +       else
  90 +               data->last_chan = 0;
  91 +#endif
  92         i2c_set_clientdata(client, muxc);
  93         data->client = client;
  94
  95 @@ -240,11 +270,16 @@ static int pca954x_probe(struct i2c_clie
  96          * that the mux is in fact present. This also
  97          * initializes the mux to disconnected state.
  98          */
  99 +#ifdef CONFIG_ARCH_LAYERSCAPE
 100 +       if (i2c_smbus_write_byte(client, data->disable_mux) < 0) {
 101 +#else
 102         if (i2c_smbus_write_byte(client, 0) < 0) {
 103 +#endif
 104                 dev_warn(&client->dev, "probe failed\n");
 105                 return -ENODEV;
 106         }
 107
 108 +#ifndef CONFIG_ARCH_LAYERSCAPE
 109         match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
 110         if (match)
 111                 data->chip = of_device_get_match_data(&client->dev);
 112 @@ -252,6 +287,7 @@ static int pca954x_probe(struct i2c_clie
 113                 data->chip = &chips[id->driver_data];
 114
 115         data->last_chan = 0;               /* force the first selection */
 116 +#endif
 117
 118         idle_disconnect_dt = of_node &&
 119                 of_property_read_bool(of_node, "i2c-mux-idle-disconnect");
 120 @@ -312,6 +348,13 @@ static int pca954x_resume(struct device
 121         struct i2c_mux_core *muxc = i2c_get_clientdata(client);
 122         struct pca954x *data = i2c_mux_priv(muxc);
 123
 124 +#ifdef CONFIG_ARCH_LAYERSCAPE
 125 +       if (data->disable_mux != 0)
 126 +               data->last_chan = data->chip->nchans;
 127 +       else
 128 +               data->last_chan = 0;
 129 +       return i2c_smbus_write_byte(client, data->disable_mux);
 130 +#endif
 131         data->last_chan = 0;
 132         return i2c_smbus_write_byte(client, 0);
 133  }