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 struct intel_quark_mfd {
56 	struct device		*dev;
57 	struct clk		*i2c_clk;
58 	struct clk_lookup	*i2c_clk_lookup;
59 };
60 
61 static const struct dmi_system_id dmi_platform_info[] = {
62 	{
63 		.matches = {
64 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "Galileo"),
65 		},
66 		.driver_data = (void *)100000,
67 	},
68 	{
69 		.matches = {
70 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
71 		},
72 		.driver_data = (void *)400000,
73 	},
74 	{
75 		.matches = {
76 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
77 			DMI_EXACT_MATCH(DMI_BOARD_ASSET_TAG,
78 					"6ES7647-0AA00-0YA2"),
79 		},
80 		.driver_data = (void *)400000,
81 	},
82 	{
83 		.matches = {
84 			DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
85 			DMI_EXACT_MATCH(DMI_BOARD_ASSET_TAG,
86 					"6ES7647-0AA00-1YA2"),
87 		},
88 		.driver_data = (void *)400000,
89 	},
90 	{}
91 };
92 
93 static struct resource intel_quark_i2c_res[] = {
94 	[INTEL_QUARK_IORES_MEM] = {
95 		.flags = IORESOURCE_MEM,
96 	},
97 	[INTEL_QUARK_IORES_IRQ] = {
98 		.flags = IORESOURCE_IRQ,
99 	},
100 };
101 
102 static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
103 	.adr = MFD_ACPI_MATCH_I2C,
104 };
105 
106 static struct resource intel_quark_gpio_res[] = {
107 	[INTEL_QUARK_IORES_MEM] = {
108 		.flags = IORESOURCE_MEM,
109 	},
110 };
111 
112 static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
113 	.adr = MFD_ACPI_MATCH_GPIO,
114 };
115 
116 static struct mfd_cell intel_quark_mfd_cells[] = {
117 	{
118 		.id = MFD_GPIO_BAR,
119 		.name = "gpio-dwapb",
120 		.acpi_match = &intel_quark_acpi_match_gpio,
121 		.num_resources = ARRAY_SIZE(intel_quark_gpio_res),
122 		.resources = intel_quark_gpio_res,
123 		.ignore_resource_conflicts = true,
124 	},
125 	{
126 		.id = MFD_I2C_BAR,
127 		.name = "i2c_designware",
128 		.acpi_match = &intel_quark_acpi_match_i2c,
129 		.num_resources = ARRAY_SIZE(intel_quark_i2c_res),
130 		.resources = intel_quark_i2c_res,
131 		.ignore_resource_conflicts = true,
132 	},
133 };
134 
135 static const struct pci_device_id intel_quark_mfd_ids[] = {
136 	{ PCI_VDEVICE(INTEL, 0x0934), },
137 	{},
138 };
139 MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
140 
141 static int intel_quark_register_i2c_clk(struct device *dev)
142 {
143 	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
144 	struct clk *i2c_clk;
145 
146 	i2c_clk = clk_register_fixed_rate(dev,
147 					  INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
148 					  0, INTEL_QUARK_I2C_CLK_HZ);
149 	if (IS_ERR(i2c_clk))
150 		return PTR_ERR(i2c_clk);
151 
152 	quark_mfd->i2c_clk = i2c_clk;
153 	quark_mfd->i2c_clk_lookup = clkdev_create(i2c_clk, NULL,
154 						INTEL_QUARK_I2C_CONTROLLER_CLK);
155 
156 	if (!quark_mfd->i2c_clk_lookup) {
157 		clk_unregister(quark_mfd->i2c_clk);
158 		dev_err(dev, "Fixed clk register failed\n");
159 		return -ENOMEM;
160 	}
161 
162 	return 0;
163 }
164 
165 static void intel_quark_unregister_i2c_clk(struct device *dev)
166 {
167 	struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
168 
169 	if (!quark_mfd->i2c_clk_lookup)
170 		return;
171 
172 	clkdev_drop(quark_mfd->i2c_clk_lookup);
173 	clk_unregister(quark_mfd->i2c_clk);
174 }
175 
176 static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
177 {
178 	const struct dmi_system_id *dmi_id;
179 	struct dw_i2c_platform_data *pdata;
180 	struct resource *res = (struct resource *)cell->resources;
181 	struct device *dev = &pdev->dev;
182 
183 	res[INTEL_QUARK_IORES_MEM].start =
184 		pci_resource_start(pdev, MFD_I2C_BAR);
185 	res[INTEL_QUARK_IORES_MEM].end =
186 		pci_resource_end(pdev, MFD_I2C_BAR);
187 
188 	res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
189 	res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
190 
191 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
192 	if (!pdata)
193 		return -ENOMEM;
194 
195 	/* Normal mode by default */
196 	pdata->i2c_scl_freq = 100000;
197 
198 	dmi_id = dmi_first_match(dmi_platform_info);
199 	if (dmi_id)
200 		pdata->i2c_scl_freq = (uintptr_t)dmi_id->driver_data;
201 
202 	cell->platform_data = pdata;
203 	cell->pdata_size = sizeof(*pdata);
204 
205 	return 0;
206 }
207 
208 static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
209 {
210 	struct dwapb_platform_data *pdata;
211 	struct resource *res = (struct resource *)cell->resources;
212 	struct device *dev = &pdev->dev;
213 
214 	res[INTEL_QUARK_IORES_MEM].start =
215 		pci_resource_start(pdev, MFD_GPIO_BAR);
216 	res[INTEL_QUARK_IORES_MEM].end =
217 		pci_resource_end(pdev, MFD_GPIO_BAR);
218 
219 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
220 	if (!pdata)
221 		return -ENOMEM;
222 
223 	/* For intel quark x1000, it has only one port: portA */
224 	pdata->nports = INTEL_QUARK_GPIO_NPORTS;
225 	pdata->properties = devm_kcalloc(dev, pdata->nports,
226 					 sizeof(*pdata->properties),
227 					 GFP_KERNEL);
228 	if (!pdata->properties)
229 		return -ENOMEM;
230 
231 	/* Set the properties for portA */
232 	pdata->properties->fwnode	= NULL;
233 	pdata->properties->idx		= 0;
234 	pdata->properties->ngpio	= INTEL_QUARK_MFD_NGPIO;
235 	pdata->properties->gpio_base	= INTEL_QUARK_MFD_GPIO_BASE;
236 	pdata->properties->irq[0]	= pdev->irq;
237 	pdata->properties->has_irq	= true;
238 	pdata->properties->irq_shared	= true;
239 
240 	cell->platform_data = pdata;
241 	cell->pdata_size = sizeof(*pdata);
242 
243 	return 0;
244 }
245 
246 static int intel_quark_mfd_probe(struct pci_dev *pdev,
247 				 const struct pci_device_id *id)
248 {
249 	struct intel_quark_mfd *quark_mfd;
250 	int ret;
251 
252 	ret = pcim_enable_device(pdev);
253 	if (ret)
254 		return ret;
255 
256 	quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
257 	if (!quark_mfd)
258 		return -ENOMEM;
259 
260 	quark_mfd->dev = &pdev->dev;
261 	dev_set_drvdata(&pdev->dev, quark_mfd);
262 
263 	ret = intel_quark_register_i2c_clk(&pdev->dev);
264 	if (ret)
265 		return ret;
266 
267 	ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);
268 	if (ret)
269 		goto err_unregister_i2c_clk;
270 
271 	ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);
272 	if (ret)
273 		goto err_unregister_i2c_clk;
274 
275 	ret = mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
276 			      ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
277 			      NULL);
278 	if (ret)
279 		goto err_unregister_i2c_clk;
280 
281 	return 0;
282 
283 err_unregister_i2c_clk:
284 	intel_quark_unregister_i2c_clk(&pdev->dev);
285 	return ret;
286 }
287 
288 static void intel_quark_mfd_remove(struct pci_dev *pdev)
289 {
290 	intel_quark_unregister_i2c_clk(&pdev->dev);
291 	mfd_remove_devices(&pdev->dev);
292 }
293 
294 static struct pci_driver intel_quark_mfd_driver = {
295 	.name		= "intel_quark_mfd_i2c_gpio",
296 	.id_table	= intel_quark_mfd_ids,
297 	.probe		= intel_quark_mfd_probe,
298 	.remove		= intel_quark_mfd_remove,
299 };
300 
301 module_pci_driver(intel_quark_mfd_driver);
302 
303 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
304 MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
305 MODULE_LICENSE("GPL v2");
306