1/*
2 * Intel Quark MFD PCI driver for I2C & GPIO
3 *
4 * Copyright(c) 2014 Intel Corporation.
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
9 *
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13 * more details.
14 *
15 * Intel Quark PCI device for I2C and GPIO controller sharing the same
16 * PCI function. This PCI driver will split the 2 devices into their
17 * respective drivers.
18 */
19
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/pci.h>
23#include <linux/mfd/core.h>
24#include <linux/clkdev.h>
25#include <linux/clk-provider.h>
26#include <linux/dmi.h>
27#include <linux/platform_data/gpio-dwapb.h>
28#include <linux/platform_data/i2c-designware.h>
29
30/* PCI BAR for register base address */
31#define MFD_I2C_BAR		0
32#define MFD_GPIO_BAR		1
33
34/* The base GPIO number under GPIOLIB framework */
35#define INTEL_QUARK_MFD_GPIO_BASE	8
36
37/* The default number of South-Cluster GPIO on Quark. */
38#define INTEL_QUARK_MFD_NGPIO		8
39
40/* The DesignWare GPIO ports on Quark. */
41#define INTEL_QUARK_GPIO_NPORTS	1
42
43#define INTEL_QUARK_IORES_MEM	0
44#define INTEL_QUARK_IORES_IRQ	1
45
46#define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
47
48/* The Quark I2C controller source clock */
49#define INTEL_QUARK_I2C_CLK_HZ	33000000
50
51#define INTEL_QUARK_I2C_NCLK	1
52
53struct intel_quark_mfd {
54	struct pci_dev		*pdev;
55	struct clk		*i2c_clk;
56	struct clk_lookup	*i2c_clk_lookup;
57};
58
59struct i2c_mode_info {
60	const char *name;
61	unsigned int i2c_scl_freq;
62};
63
64static const struct i2c_mode_info platform_i2c_mode_info[] = {
65	{
66		.name = "Galileo",
67		.i2c_scl_freq = 100000,
68	},
69	{
70		.name = "GalileoGen2",
71		.i2c_scl_freq = 400000,
72	},
73	{}
74};
75
76static struct resource intel_quark_i2c_res[] = {
77	[INTEL_QUARK_IORES_MEM] = {
78		.flags = IORESOURCE_MEM,
79	},
80	[INTEL_QUARK_IORES_IRQ] = {
81		.flags = IORESOURCE_IRQ,
82	},
83};
84
85static struct resource intel_quark_gpio_res[] = {
86	[INTEL_QUARK_IORES_MEM] = {
87		.flags = IORESOURCE_MEM,
88	},
89};
90
91static struct mfd_cell intel_quark_mfd_cells[] = {
92	{
93		.id = MFD_GPIO_BAR,
94		.name = "gpio-dwapb",
95		.num_resources = ARRAY_SIZE(intel_quark_gpio_res),
96		.resources = intel_quark_gpio_res,
97		.ignore_resource_conflicts = true,
98	},
99	{
100		.id = MFD_I2C_BAR,
101		.name = "i2c_designware",
102		.num_resources = ARRAY_SIZE(intel_quark_i2c_res),
103		.resources = intel_quark_i2c_res,
104		.ignore_resource_conflicts = true,
105	},
106};
107
108static const struct pci_device_id intel_quark_mfd_ids[] = {
109	{ PCI_VDEVICE(INTEL, 0x0934), },
110	{},
111};
112MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
113
114static int intel_quark_register_i2c_clk(struct intel_quark_mfd *quark_mfd)
115{
116	struct pci_dev *pdev = quark_mfd->pdev;
117	struct clk_lookup *i2c_clk_lookup;
118	struct clk *i2c_clk;
119	int ret;
120
121	i2c_clk_lookup = devm_kcalloc(&pdev->dev, INTEL_QUARK_I2C_NCLK,
122				      sizeof(*i2c_clk_lookup), GFP_KERNEL);
123	if (!i2c_clk_lookup)
124		return -ENOMEM;
125
126	i2c_clk_lookup[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
127
128	i2c_clk = clk_register_fixed_rate(&pdev->dev,
129					  INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
130					  CLK_IS_ROOT, INTEL_QUARK_I2C_CLK_HZ);
131
132	quark_mfd->i2c_clk_lookup = i2c_clk_lookup;
133	quark_mfd->i2c_clk = i2c_clk;
134
135	ret = clk_register_clkdevs(i2c_clk, i2c_clk_lookup,
136				   INTEL_QUARK_I2C_NCLK);
137	if (ret)
138		dev_err(&pdev->dev, "Fixed clk register failed: %d\n", ret);
139
140	return ret;
141}
142
143static void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)
144{
145	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(&pdev->dev);
146
147	if (!quark_mfd->i2c_clk || !quark_mfd->i2c_clk_lookup)
148		return;
149
150	clkdev_drop(quark_mfd->i2c_clk_lookup);
151	clk_unregister(quark_mfd->i2c_clk);
152}
153
154static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
155{
156	const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
157	const struct i2c_mode_info *info;
158	struct dw_i2c_platform_data *pdata;
159	struct resource *res = (struct resource *)cell->resources;
160	struct device *dev = &pdev->dev;
161
162	res[INTEL_QUARK_IORES_MEM].start =
163		pci_resource_start(pdev, MFD_I2C_BAR);
164	res[INTEL_QUARK_IORES_MEM].end =
165		pci_resource_end(pdev, MFD_I2C_BAR);
166
167	res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
168	res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
169
170	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
171	if (!pdata)
172		return -ENOMEM;
173
174	/* Normal mode by default */
175	pdata->i2c_scl_freq = 100000;
176
177	if (board_name) {
178		for (info = platform_i2c_mode_info; info->name; info++) {
179			if (!strcmp(board_name, info->name)) {
180				pdata->i2c_scl_freq = info->i2c_scl_freq;
181				break;
182			}
183		}
184	}
185
186	cell->platform_data = pdata;
187	cell->pdata_size = sizeof(*pdata);
188
189	return 0;
190}
191
192static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
193{
194	struct dwapb_platform_data *pdata;
195	struct resource *res = (struct resource *)cell->resources;
196	struct device *dev = &pdev->dev;
197
198	res[INTEL_QUARK_IORES_MEM].start =
199		pci_resource_start(pdev, MFD_GPIO_BAR);
200	res[INTEL_QUARK_IORES_MEM].end =
201		pci_resource_end(pdev, MFD_GPIO_BAR);
202
203	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
204	if (!pdata)
205		return -ENOMEM;
206
207	/* For intel quark x1000, it has only one port: portA */
208	pdata->nports = INTEL_QUARK_GPIO_NPORTS;
209	pdata->properties = devm_kcalloc(dev, pdata->nports,
210					 sizeof(*pdata->properties),
211					 GFP_KERNEL);
212	if (!pdata->properties)
213		return -ENOMEM;
214
215	/* Set the properties for portA */
216	pdata->properties->node		= NULL;
217	pdata->properties->name		= "intel-quark-x1000-gpio-portA";
218	pdata->properties->idx		= 0;
219	pdata->properties->ngpio	= INTEL_QUARK_MFD_NGPIO;
220	pdata->properties->gpio_base	= INTEL_QUARK_MFD_GPIO_BASE;
221	pdata->properties->irq		= pdev->irq;
222	pdata->properties->irq_shared	= true;
223
224	cell->platform_data = pdata;
225	cell->pdata_size = sizeof(*pdata);
226
227	return 0;
228}
229
230static int intel_quark_mfd_probe(struct pci_dev *pdev,
231				 const struct pci_device_id *id)
232{
233	struct intel_quark_mfd *quark_mfd;
234	int ret;
235
236	ret = pcim_enable_device(pdev);
237	if (ret)
238		return ret;
239
240	quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
241	if (!quark_mfd)
242		return -ENOMEM;
243	quark_mfd->pdev = pdev;
244
245	ret = intel_quark_register_i2c_clk(quark_mfd);
246	if (ret)
247		return ret;
248
249	dev_set_drvdata(&pdev->dev, quark_mfd);
250
251	ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);
252	if (ret)
253		return ret;
254
255	ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);
256	if (ret)
257		return ret;
258
259	return mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
260			       ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
261			       NULL);
262}
263
264static void intel_quark_mfd_remove(struct pci_dev *pdev)
265{
266	intel_quark_unregister_i2c_clk(pdev);
267	mfd_remove_devices(&pdev->dev);
268}
269
270static struct pci_driver intel_quark_mfd_driver = {
271	.name		= "intel_quark_mfd_i2c_gpio",
272	.id_table	= intel_quark_mfd_ids,
273	.probe		= intel_quark_mfd_probe,
274	.remove		= intel_quark_mfd_remove,
275};
276
277module_pci_driver(intel_quark_mfd_driver);
278
279MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
280MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
281MODULE_LICENSE("GPL v2");
282