drivers/i2c/busses/i2c-pxa-pci.c

   1 /*
   2  * CE4100 PCI-I2C glue code for PXA's driver
   3  * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   4  * License: GPL v2
   5  *
   6  * The CE4100's I2C device is more or less the same one as found on PXA.
   7  * It does not support slave mode, the register slightly moved. This PCI
   8  * device provides three bars, every contains a single I2C controller.
   9  */
  10 #include <linux/init.h>
  11 #include <linux/pci.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/platform_data/i2c-pxa.h>
  14 #include <linux/of.h>
  15 #include <linux/of_device.h>
  16 #include <linux/of_address.h>
  17
  18 #define CE4100_PCI_I2C_DEVS     3
  19
  20 struct ce4100_devices {
  21         struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
  22 };
  23
  24 static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar)
  25 {
  26         struct platform_device *pdev;
  27         struct i2c_pxa_platform_data pdata;
  28         struct resource res[2];
  29         struct device_node *child;
  30         static int devnum;
  31         int ret;
  32
  33         memset(&pdata, 0, sizeof(struct i2c_pxa_platform_data));
  34         memset(&res, 0, sizeof(res));
  35
  36         res[0].flags = IORESOURCE_MEM;
  37         res[0].start = pci_resource_start(dev, bar);
  38         res[0].end = pci_resource_end(dev, bar);
  39
  40         res[1].flags = IORESOURCE_IRQ;
  41         res[1].start = dev->irq;
  42         res[1].end = dev->irq;
  43
  44         for_each_child_of_node(dev->dev.of_node, child) {
  45                 const void *prop;
  46                 struct resource r;
  47                 int ret;
  48
  49                 ret = of_address_to_resource(child, 0, &r);
  50                 if (ret < 0)
  51                         continue;
  52                 if (r.start != res[0].start)
  53                         continue;
  54                 if (r.end != res[0].end)
  55                         continue;
  56                 if (r.flags != res[0].flags)
  57                         continue;
  58
  59                 prop = of_get_property(child, "fast-mode", NULL);
  60                 if (prop)
  61                         pdata.fast_mode = 1;
  62
  63                 break;
  64         }
  65
  66         if (!child) {
  67                 dev_err(&dev->dev, "failed to match a DT node for bar %d.\n",
  68                                 bar);
  69                 ret = -EINVAL;
  70                 goto out;
  71         }
  72
  73         pdev = platform_device_alloc("ce4100-i2c", devnum);
  74         if (!pdev) {
  75                 of_node_put(child);
  76                 ret = -ENOMEM;
  77                 goto out;
  78         }
  79         pdev->dev.parent = &dev->dev;
  80         pdev->dev.of_node = child;
  81
  82         ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
  83         if (ret)
  84                 goto err;
  85
  86         ret = platform_device_add_data(pdev, &pdata, sizeof(pdata));
  87         if (ret)
  88                 goto err;
  89
  90         ret = platform_device_add(pdev);
  91         if (ret)
  92                 goto err;
  93         devnum++;
  94         return pdev;
  95 err:
  96         platform_device_put(pdev);
  97 out:
  98         return ERR_PTR(ret);
  99 }
 100
 101 static int ce4100_i2c_probe(struct pci_dev *dev,
 102                 const struct pci_device_id *ent)
 103 {
 104         int ret;
 105         int i;
 106         struct ce4100_devices *sds;
 107
 108         ret = pci_enable_device_mem(dev);
 109         if (ret)
 110                 return ret;
 111
 112         if (!dev->dev.of_node) {
 113                 dev_err(&dev->dev, "Missing device tree node.\n");
 114                 return -EINVAL;
 115         }
 116         sds = kzalloc(sizeof(*sds), GFP_KERNEL);
 117         if (!sds) {
 118                 ret = -ENOMEM;
 119                 goto err_mem;
 120         }
 121
 122         for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) {
 123                 sds->pdev[i] = add_i2c_device(dev, i);
 124                 if (IS_ERR(sds->pdev[i])) {
 125                         ret = PTR_ERR(sds->pdev[i]);
 126                         while (--i >= 0)
 127                                 platform_device_unregister(sds->pdev[i]);
 128                         goto err_dev_add;
 129                 }
 130         }
 131         pci_set_drvdata(dev, sds);
 132         return 0;
 133
 134 err_dev_add:
 135         kfree(sds);
 136 err_mem:
 137         pci_disable_device(dev);
 138         return ret;
 139 }
 140
 141 static const struct pci_device_id ce4100_i2c_devices[] = {
 142         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
 143         { },
 144 };
 145
 146 static struct pci_driver ce4100_i2c_driver = {
 147         .driver = {
 148                 .suppress_bind_attrs = true,
 149         },
 150         .name           = "ce4100_i2c",
 151         .id_table       = ce4100_i2c_devices,
 152         .probe          = ce4100_i2c_probe,
 153 };
 154 builtin_pci_driver(ce4100_i2c_driver);