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/* ACPI _ADR value to match the child node */
35#define MFD_ACPI_MATCH_GPIO	0ULL
36#define MFD_ACPI_MATCH_I2C	1ULL
37
38/* The base GPIO number under GPIOLIB framework */
39#define INTEL_QUARK_MFD_GPIO_BASE	8
40
41/* The default number of South-Cluster GPIO on Quark. */
42#define INTEL_QUARK_MFD_NGPIO		8
43
44/* The DesignWare GPIO ports on Quark. */
45#define INTEL_QUARK_GPIO_NPORTS	1
46
47#define INTEL_QUARK_IORES_MEM	0
48#define INTEL_QUARK_IORES_IRQ	1
49
50#define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
51
52/* The Quark I2C controller source clock */
53#define INTEL_QUARK_I2C_CLK_HZ	33000000
54
55#define INTEL_QUARK_I2C_NCLK	1
56
57struct intel_quark_mfd {
58	struct pci_dev		*pdev;
59	struct clk		*i2c_clk;
60	struct clk_lookup	*i2c_clk_lookup;
61};
62
63struct i2c_mode_info {
64	const char *name;
65	unsigned int i2c_scl_freq;
66};
67
68static const struct i2c_mode_info platform_i2c_mode_info[] = {
69	{
70		.name = "Galileo",
71		.i2c_scl_freq = 100000,
72	},
73	{
74		.name = "GalileoGen2",
75		.i2c_scl_freq = 400000,
76	},
77	{}
78};
79
80static struct resource intel_quark_i2c_res[] = {
81	[INTEL_QUARK_IORES_MEM] = {
82		.flags = IORESOURCE_MEM,
83	},
84	[INTEL_QUARK_IORES_IRQ] = {
85		.flags = IORESOURCE_IRQ,
86	},
87};
88
89static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
90	.adr = MFD_ACPI_MATCH_I2C,
91};
92
93static struct resource intel_quark_gpio_res[] = {
94	[INTEL_QUARK_IORES_MEM] = {
95		.flags = IORESOURCE_MEM,
96	},
97};
98
99static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
100	.adr = MFD_ACPI_MATCH_GPIO,
101};
102
103static struct mfd_cell intel_quark_mfd_cells[] = {
104	{
105		.id = MFD_GPIO_BAR,
106		.name = "gpio-dwapb",
107		.acpi_match = &intel_quark_acpi_match_gpio,
108		.num_resources = ARRAY_SIZE(intel_quark_gpio_res),
109		.resources = intel_quark_gpio_res,
110		.ignore_resource_conflicts = true,
111	},
112	{
113		.id = MFD_I2C_BAR,
114		.name = "i2c_designware",
115		.acpi_match = &intel_quark_acpi_match_i2c,
116		.num_resources = ARRAY_SIZE(intel_quark_i2c_res),
117		.resources = intel_quark_i2c_res,
118		.ignore_resource_conflicts = true,
119	},
120};
121
122static const struct pci_device_id intel_quark_mfd_ids[] = {
123	{ PCI_VDEVICE(INTEL, 0x0934), },
124	{},
125};
126MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
127
128static int intel_quark_register_i2c_clk(struct intel_quark_mfd *quark_mfd)
129{
130	struct pci_dev *pdev = quark_mfd->pdev;
131	struct clk_lookup *i2c_clk_lookup;
132	struct clk *i2c_clk;
133	int ret;
134
135	i2c_clk_lookup = devm_kcalloc(&pdev->dev, INTEL_QUARK_I2C_NCLK,
136				      sizeof(*i2c_clk_lookup), GFP_KERNEL);
137	if (!i2c_clk_lookup)
138		return -ENOMEM;
139
140	i2c_clk_lookup[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
141
142	i2c_clk = clk_register_fixed_rate(&pdev->dev,
143					  INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
144					  CLK_IS_ROOT, INTEL_QUARK_I2C_CLK_HZ);
145
146	quark_mfd->i2c_clk_lookup = i2c_clk_lookup;
147	quark_mfd->i2c_clk = i2c_clk;
148
149	ret = clk_register_clkdevs(i2c_clk, i2c_clk_lookup,
150				   INTEL_QUARK_I2C_NCLK);
151	if (ret)
152		dev_err(&pdev->dev, "Fixed clk register failed: %d\n", ret);
153
154	return ret;
155}
156
157static void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)
158{
159	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(&pdev->dev);
160
161	if (!quark_mfd->i2c_clk || !quark_mfd->i2c_clk_lookup)
162		return;
163
164	clkdev_drop(quark_mfd->i2c_clk_lookup);
165	clk_unregister(quark_mfd->i2c_clk);
166}
167
168static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
169{
170	const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
171	const struct i2c_mode_info *info;
172	struct dw_i2c_platform_data *pdata;
173	struct resource *res = (struct resource *)cell->resources;
174	struct device *dev = &pdev->dev;
175
176	res[INTEL_QUARK_IORES_MEM].start =
177		pci_resource_start(pdev, MFD_I2C_BAR);
178	res[INTEL_QUARK_IORES_MEM].end =
179		pci_resource_end(pdev, MFD_I2C_BAR);
180
181	res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
182	res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
183
184	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
185	if (!pdata)
186		return -ENOMEM;
187
188	/* Normal mode by default */
189	pdata->i2c_scl_freq = 100000;
190
191	if (board_name) {
192		for (info = platform_i2c_mode_info; info->name; info++) {
193			if (!strcmp(board_name, info->name)) {
194				pdata->i2c_scl_freq = info->i2c_scl_freq;
195				break;
196			}
197		}
198	}
199
200	cell->platform_data = pdata;
201	cell->pdata_size = sizeof(*pdata);
202
203	return 0;
204}
205
206static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
207{
208	struct dwapb_platform_data *pdata;
209	struct resource *res = (struct resource *)cell->resources;
210	struct device *dev = &pdev->dev;
211
212	res[INTEL_QUARK_IORES_MEM].start =
213		pci_resource_start(pdev, MFD_GPIO_BAR);
214	res[INTEL_QUARK_IORES_MEM].end =
215		pci_resource_end(pdev, MFD_GPIO_BAR);
216
217	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
218	if (!pdata)
219		return -ENOMEM;
220
221	/* For intel quark x1000, it has only one port: portA */
222	pdata->nports = INTEL_QUARK_GPIO_NPORTS;
223	pdata->properties = devm_kcalloc(dev, pdata->nports,
224					 sizeof(*pdata->properties),
225					 GFP_KERNEL);
226	if (!pdata->properties)
227		return -ENOMEM;
228
229	/* Set the properties for portA */
230	pdata->properties->node		= NULL;
231	pdata->properties->name		= "intel-quark-x1000-gpio-portA";
232	pdata->properties->idx		= 0;
233	pdata->properties->ngpio	= INTEL_QUARK_MFD_NGPIO;
234	pdata->properties->gpio_base	= INTEL_QUARK_MFD_GPIO_BASE;
235	pdata->properties->irq		= pdev->irq;
236	pdata->properties->irq_shared	= true;
237
238	cell->platform_data = pdata;
239	cell->pdata_size = sizeof(*pdata);
240
241	return 0;
242}
243
244static int intel_quark_mfd_probe(struct pci_dev *pdev,
245				 const struct pci_device_id *id)
246{
247	struct intel_quark_mfd *quark_mfd;
248	int ret;
249
250	ret = pcim_enable_device(pdev);
251	if (ret)
252		return ret;
253
254	quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
255	if (!quark_mfd)
256		return -ENOMEM;
257	quark_mfd->pdev = pdev;
258
259	ret = intel_quark_register_i2c_clk(quark_mfd);
260	if (ret)
261		return ret;
262
263	dev_set_drvdata(&pdev->dev, quark_mfd);
264
265	ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);
266	if (ret)
267		return ret;
268
269	ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);
270	if (ret)
271		return ret;
272
273	return mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
274			       ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
275			       NULL);
276}
277
278static void intel_quark_mfd_remove(struct pci_dev *pdev)
279{
280	intel_quark_unregister_i2c_clk(pdev);
281	mfd_remove_devices(&pdev->dev);
282}
283
284static struct pci_driver intel_quark_mfd_driver = {
285	.name		= "intel_quark_mfd_i2c_gpio",
286	.id_table	= intel_quark_mfd_ids,
287	.probe		= intel_quark_mfd_probe,
288	.remove		= intel_quark_mfd_remove,
289};
290
291module_pci_driver(intel_quark_mfd_driver);
292
293MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
294MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
295MODULE_LICENSE("GPL v2");
296