cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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i2c-pxa-pci.c (3351B)

      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_device.h>
     16#include <linux/of_address.h>
     17
     18#define CE4100_PCI_I2C_DEVS	3
     19
     20struct ce4100_devices {
     21	struct platform_device *pdev[CE4100_PCI_I2C_DEVS];
     22};
     23
     24static 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;
     95err:
     96	platform_device_put(pdev);
     97out:
     98	return ERR_PTR(ret);
     99}
    100
    101static 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
    134err_dev_add:
    135	kfree(sds);
    136err_mem:
    137	pci_disable_device(dev);
    138	return ret;
    139}
    140
    141static const struct pci_device_id ce4100_i2c_devices[] = {
    142	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x2e68)},
    143	{ },
    144};
    145
    146static 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};
    154builtin_pci_driver(ce4100_i2c_driver);