xref: /openbmc/linux/drivers/i2c/busses/i2c-pxa-pci.c (revision f3539c12)
1 /*
2  * The CE4100's I2C device is more or less the same one as found on PXA.
3  * It does not support slave mode, the register slightly moved. This PCI
4  * device provides three bars, every contains a single I2C controller.
5  */
6 #include <linux/module.h>
7 #include <linux/pci.h>
8 #include <linux/platform_device.h>
9 #include <linux/i2c/pxa-i2c.h>
10 #include <linux/of.h>
11 #include <linux/of_device.h>
12 #include <linux/of_address.h>
13 
14 #define CE4100_PCI_I2C_DEVS	3
15 
16 struct ce4100_devices {
17 	struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
18 };
19 
20 static struct platform_device *add_i2c_device(struct pci_dev *dev, int bar)
21 {
22 	struct platform_device *pdev;
23 	struct i2c_pxa_platform_data pdata;
24 	struct resource res[2];
25 	struct device_node *child;
26 	static int devnum;
27 	int ret;
28 
29 	memset(&pdata, 0, sizeof(struct i2c_pxa_platform_data));
30 	memset(&res, 0, sizeof(res));
31 
32 	res[0].flags = IORESOURCE_MEM;
33 	res[0].start = pci_resource_start(dev, bar);
34 	res[0].end = pci_resource_end(dev, bar);
35 
36 	res[1].flags = IORESOURCE_IRQ;
37 	res[1].start = dev->irq;
38 	res[1].end = dev->irq;
39 
40 	for_each_child_of_node(dev->dev.of_node, child) {
41 		const void *prop;
42 		struct resource r;
43 		int ret;
44 
45 		ret = of_address_to_resource(child, 0, &r);
46 		if (ret < 0)
47 			continue;
48 		if (r.start != res[0].start)
49 			continue;
50 		if (r.end != res[0].end)
51 			continue;
52 		if (r.flags != res[0].flags)
53 			continue;
54 
55 		prop = of_get_property(child, "fast-mode", NULL);
56 		if (prop)
57 			pdata.fast_mode = 1;
58 
59 		break;
60 	}
61 
62 	if (!child) {
63 		dev_err(&dev->dev, "failed to match a DT node for bar %d.\n",
64 				bar);
65 		ret = -EINVAL;
66 		goto out;
67 	}
68 
69 	pdev = platform_device_alloc("ce4100-i2c", devnum);
70 	if (!pdev) {
71 		of_node_put(child);
72 		ret = -ENOMEM;
73 		goto out;
74 	}
75 	pdev->dev.parent = &dev->dev;
76 	pdev->dev.of_node = child;
77 
78 	ret = platform_device_add_resources(pdev, res, ARRAY_SIZE(res));
79 	if (ret)
80 		goto err;
81 
82 	ret = platform_device_add_data(pdev, &pdata, sizeof(pdata));
83 	if (ret)
84 		goto err;
85 
86 	ret = platform_device_add(pdev);
87 	if (ret)
88 		goto err;
89 	devnum++;
90 	return pdev;
91 err:
92 	platform_device_put(pdev);
93 out:
94 	return ERR_PTR(ret);
95 }
96 
97 static int ce4100_i2c_probe(struct pci_dev *dev,
98 		const struct pci_device_id *ent)
99 {
100 	int ret;
101 	int i;
102 	struct ce4100_devices *sds;
103 
104 	ret = pci_enable_device_mem(dev);
105 	if (ret)
106 		return ret;
107 
108 	if (!dev->dev.of_node) {
109 		dev_err(&dev->dev, "Missing device tree node.\n");
110 		return -EINVAL;
111 	}
112 	sds = kzalloc(sizeof(*sds), GFP_KERNEL);
113 	if (!sds) {
114 		ret = -ENOMEM;
115 		goto err_mem;
116 	}
117 
118 	for (i = 0; i < ARRAY_SIZE(sds->pdev); i++) {
119 		sds->pdev[i] = add_i2c_device(dev, i);
120 		if (IS_ERR(sds->pdev[i])) {
121 			ret = PTR_ERR(sds->pdev[i]);
122 			while (--i >= 0)
123 				platform_device_unregister(sds->pdev[i]);
124 			goto err_dev_add;
125 		}
126 	}
127 	pci_set_drvdata(dev, sds);
128 	return 0;
129 
130 err_dev_add:
131 	kfree(sds);
132 err_mem:
133 	pci_disable_device(dev);
134 	return ret;
135 }
136 
137 static void ce4100_i2c_remove(struct pci_dev *dev)
138 {
139 	struct ce4100_devices *sds;
140 	unsigned int i;
141 
142 	sds = pci_get_drvdata(dev);
143 
144 	for (i = 0; i < ARRAY_SIZE(sds->pdev); i++)
145 		platform_device_unregister(sds->pdev[i]);
146 
147 	pci_disable_device(dev);
148 	kfree(sds);
149 }
150 
151 static const struct pci_device_id ce4100_i2c_devices[] = {
152 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
153 	{ },
154 };
155 MODULE_DEVICE_TABLE(pci, ce4100_i2c_devices);
156 
157 static struct pci_driver ce4100_i2c_driver = {
158 	.name           = "ce4100_i2c",
159 	.id_table       = ce4100_i2c_devices,
160 	.probe          = ce4100_i2c_probe,
161 	.remove         = ce4100_i2c_remove,
162 };
163 
164 module_pci_driver(ce4100_i2c_driver);
165 
166 MODULE_DESCRIPTION("CE4100 PCI-I2C glue code for PXA's driver");
167 MODULE_LICENSE("GPL v2");
168 MODULE_AUTHOR("Sebastian Andrzej Siewior <bigeasy@linutronix.de>");
169