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 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_address.h>
16
17#define CE4100_PCI_I2C_DEVS 3
18
19struct ce4100_devices {
20 struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
21};
22
23static 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(dev: child, index: 0, r: &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(node: child, name: "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(name: "ce4100-i2c", id: devnum);
73 if (!pdev) {
74 of_node_put(node: 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, data: &pdata, size: 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;
94err:
95 platform_device_put(pdev);
96out:
97 return ERR_PTR(error: ret);
98}
99
100static 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(pdev: 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(size: 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, bar: i);
121 if (IS_ERR(ptr: sds->pdev[i])) {
122 ret = PTR_ERR(ptr: 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(pdev: dev, data: sds);
129 return 0;
130
131err_dev_add:
132 kfree(objp: sds);
133 return ret;
134}
135
136static const struct pci_device_id ce4100_i2c_devices[] = {
137 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
138 { },
139};
140
141static 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};
149builtin_pci_driver(ce4100_i2c_driver);
150

source code of linux/drivers/i2c/busses/i2c-pxa-pci.c