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 diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
  17 index 47fc1f1a..a35c366b 100644
  18 --- a/drivers/i2c/busses/i2c-imx.c
  19 +++ b/drivers/i2c/busses/i2c-imx.c
  20 @@ -889,6 +889,14 @@ static int i2c_imx_xfer(struct i2c_adapter *adapter,
  21
  22         dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
  23
  24 +       /*
  25 +        * workround for ERR010027: ensure that the I2C BUS is idle
  26 +        * before switching to master mode and attempting a Start cycle
  27 +        */
  28 +       result =  i2c_imx_bus_busy(i2c_imx, 0);
  29 +       if (result)
  30 +               goto out;
  31 +
  32         result = pm_runtime_get_sync(i2c_imx->adapter.dev.parent);
  33         if (result < 0)
  34                 goto out;
  35 @@ -1100,7 +1108,7 @@ static int i2c_imx_probe(struct platform_device *pdev)
  36         }
  37
  38         /* Request IRQ */
  39 -       ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
  40 +       ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, IRQF_SHARED,
  41                                 pdev->name, i2c_imx);
  42         if (ret) {
  43                 dev_err(&pdev->dev, "can't claim irq %d\n", irq);
  44 diff --git a/drivers/i2c/muxes/i2c-mux-pca954x.c b/drivers/i2c/muxes/i2c-mux-pca954x.c
  45 index 9c4ac26c..3c27ab84 100644
  46 --- a/drivers/i2c/muxes/i2c-mux-pca954x.c
  47 +++ b/drivers/i2c/muxes/i2c-mux-pca954x.c
  48 @@ -74,6 +74,7 @@ struct pca954x {
  49         u8 last_chan;           /* last register value */
  50         u8 deselect;
  51         struct i2c_client *client;
  52 +       u8 disable_mux;         /* do not disable mux if val not 0 */
  53  };
  54
  55  /* Provide specs for the PCA954x types we know about */
  56 @@ -196,6 +197,13 @@ static int pca954x_deselect_mux(struct i2c_mux_core *muxc, u32 chan)
  57         if (!(data->deselect & (1 << chan)))
  58                 return 0;
  59
  60 +#ifdef CONFIG_ARCH_LAYERSCAPE
  61 +       if (data->disable_mux != 0)
  62 +               data->last_chan = data->chip->nchans;
  63 +       else
  64 +               data->last_chan = 0;
  65 +       return pca954x_reg_write(muxc->parent, client, data->disable_mux);
  66 +#endif
  67         /* Deselect active channel */
  68         data->last_chan = 0;
  69         return pca954x_reg_write(muxc->parent, client, data->last_chan);
  70 @@ -228,6 +236,28 @@ static int pca954x_probe(struct i2c_client *client,
  71                 return -ENOMEM;
  72         data = i2c_mux_priv(muxc);
  73
  74 +#ifdef CONFIG_ARCH_LAYERSCAPE
  75 +       /* The point here is that you must not disable a mux if there
  76 +        * are no pullups on the input or you mess up the I2C. This
  77 +        * needs to be put into the DTS really as the kernel cannot
  78 +        * know this otherwise.
  79 +        */
  80 +       match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
  81 +       if (match)
  82 +               data->chip = of_device_get_match_data(&client->dev);
  83 +       else
  84 +               data->chip = &chips[id->driver_data];
  85 +
  86 +       data->disable_mux = of_node &&
  87 +               of_property_read_bool(of_node, "i2c-mux-never-disable") &&
  88 +               data->chip->muxtype == pca954x_ismux ?
  89 +               data->chip->enable : 0;
  90 +       /* force the first selection */
  91 +       if (data->disable_mux != 0)
  92 +               data->last_chan = data->chip->nchans;
  93 +       else
  94 +               data->last_chan = 0;
  95 +#endif
  96         i2c_set_clientdata(client, muxc);
  97         data->client = client;
  98
  99 @@ -240,11 +270,16 @@ static int pca954x_probe(struct i2c_client *client,
 100          * that the mux is in fact present. This also
 101          * initializes the mux to disconnected state.
 102          */
 103 +#ifdef CONFIG_ARCH_LAYERSCAPE
 104 +       if (i2c_smbus_write_byte(client, data->disable_mux) < 0) {
 105 +#else
 106         if (i2c_smbus_write_byte(client, 0) < 0) {
 107 +#endif
 108                 dev_warn(&client->dev, "probe failed\n");
 109                 return -ENODEV;
 110         }
 111
 112 +#ifndef CONFIG_ARCH_LAYERSCAPE
 113         match = of_match_device(of_match_ptr(pca954x_of_match), &client->dev);
 114         if (match)
 115                 data->chip = of_device_get_match_data(&client->dev);
 116 @@ -252,6 +287,7 @@ static int pca954x_probe(struct i2c_client *client,
 117                 data->chip = &chips[id->driver_data];
 118
 119         data->last_chan = 0;               /* force the first selection */
 120 +#endif
 121
 122         idle_disconnect_dt = of_node &&
 123                 of_property_read_bool(of_node, "i2c-mux-idle-disconnect");
 124 @@ -312,6 +348,13 @@ static int pca954x_resume(struct device *dev)
 125         struct i2c_mux_core *muxc = i2c_get_clientdata(client);
 126         struct pca954x *data = i2c_mux_priv(muxc);
 127
 128 +#ifdef CONFIG_ARCH_LAYERSCAPE
 129 +       if (data->disable_mux != 0)
 130 +               data->last_chan = data->chip->nchans;
 131 +       else
 132 +               data->last_chan = 0;
 133 +       return i2c_smbus_write_byte(client, data->disable_mux);
 134 +#endif
 135         data->last_chan = 0;
 136         return i2c_smbus_write_byte(client, 0);
 137  }
 138 --
 139 2.14.1
 140