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

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * CE4100 PCI-I2C glue code for PXA's driver
   4  * Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   5  *
   6  * The CE4100's I2C device is more or less the same one as found on PXA.
   7  * It does not support target 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_address.h>
  16
  17 #define CE4100_PCI_I2C_DEVS     3
  18
  19 struct ce4100_devices {
  20         struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
  21 };
  22
  23 static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar)
  24 {
  25         struct platform_device *pdev;
  26         struct i2c_pxa_platform_data pdata;
  27         struct resource res[2];
  28         struct device_node *child;
  29         static int devnum;
  30         int ret;
  31
  32         memset(&pdata, 0, sizeof(struct i2c_pxa_platform_data));
  33         memset(&res, 0, sizeof(res));
  34
  35         res[0].flags = IORESOURCE_MEM;
  36         res[0].start = pci_resource_start(dev, bar);
  37         res[0].end = pci_resource_end(dev, bar);
  38
  39         res[1].flags = IORESOURCE_IRQ;
  40         res[1].start = dev->irq;
  41         res[1].end = dev->irq;
  42
  43         for_each_child_of_node(dev->dev.of_node, child) {
  44                 const void *prop;
  45                 struct resource r;
  46                 int ret;
  47
  48                 ret = of_address_to_resource(child, 0, &r);
  49                 if (ret < 0)
  50                         continue;
  51                 if (r.start != res[0].start)
  52                         continue;
  53                 if (r.end != res[0].end)
  54                         continue;
  55                 if (r.flags != res[0].flags)
  56                         continue;
  57
  58                 prop = of_get_property(child, "fast-mode", NULL);
  59                 if (prop)
  60                         pdata.fast_mode = 1;
  61
  62                 break;
  63         }
  64
  65         if (!child) {
  66                 dev_err(&dev->dev, "failed to match a DT node for bar %d.\n",
  67                                 bar);
  68                 ret = -EINVAL;
  69                 goto out;
  70         }
  71
  72         pdev = platform_device_alloc("ce4100-i2c", devnum);
  73         if (!pdev) {
  74                 of_node_put(child);
  75                 ret = -ENOMEM;
  76                 goto out;
  77         }
  78         pdev->dev.parent = &dev->dev;
  79         pdev->dev.of_node = child;
  80
  81         ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
  82         if (ret)
  83                 goto err;
  84
  85         ret = platform_device_add_data(pdev, &pdata, sizeof(pdata));
  86         if (ret)
  87                 goto err;
  88
  89         ret = platform_device_add(pdev);
  90         if (ret)
  91                 goto err;
  92         devnum++;
  93         return pdev;
  94 err:
  95         platform_device_put(pdev);
  96 out:
  97         return ERR_PTR(ret);
  98 }
  99
 100 static int ce4100_i2c_probe(struct pci_dev *dev,
 101                 const struct pci_device_id *ent)
 102 {
 103         int ret;
 104         int i;
 105         struct ce4100_devices *sds;
 106
 107         ret = pcim_enable_device(dev);
 108         if (ret)
 109                 return ret;
 110
 111         if (!dev->dev.of_node) {
 112                 dev_err(&dev->dev, "Missing device tree node.\n");
 113                 return -EINVAL;
 114         }
 115         sds = kzalloc(sizeof(*sds), GFP_KERNEL);
 116         if (!sds)
 117                 return -ENOMEM;
 118
 119         for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) {
 120                 sds->pdev[i] = add_i2c_device(dev, i);
 121                 if (IS_ERR(sds->pdev[i])) {
 122                         ret = PTR_ERR(sds->pdev[i]);
 123                         while (--i >= 0)
 124                                 platform_device_unregister(sds->pdev[i]);
 125                         goto err_dev_add;
 126                 }
 127         }
 128         pci_set_drvdata(dev, sds);
 129         return 0;
 130
 131 err_dev_add:
 132         kfree(sds);
 133         return ret;
 134 }
 135
 136 static const struct pci_device_id ce4100_i2c_devices[] = {
 137         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
 138         { }
 139 };
 140
 141 static struct pci_driver ce4100_i2c_driver = {
 142         .driver = {
 143                 .suppress_bind_attrs = true,
 144         },
 145         .name           = "ce4100_i2c",
 146         .id_table       = ce4100_i2c_devices,
 147         .probe          = ce4100_i2c_probe,
 148 };
 149 builtin_pci_driver(ce4100_i2c_driver);