xref: /linux/drivers/gpio/gpio-pch.c (revision 5f00bcb38ef9a980a33c6dbdc0044964b05f22dd)
1 /*
2  * Copyright (C) 2010 OKI SEMICONDUCTOR Co., LTD.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 2 of the License.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
16  */
17 #include <linux/kernel.h>
18 #include <linux/pci.h>
19 #include <linux/gpio.h>
20 
21 #define PCH_GPIO_ALL_PINS	0xfff /* Mask for GPIO pins 0 to 11 */
22 #define GPIO_NUM_PINS	12	/* Specifies number of GPIO PINS GPIO0-GPIO11 */
23 
24 struct pch_regs {
25 	u32	ien;
26 	u32	istatus;
27 	u32	idisp;
28 	u32	iclr;
29 	u32	imask;
30 	u32	imaskclr;
31 	u32	po;
32 	u32	pi;
33 	u32	pm;
34 	u32	im0;
35 	u32	im1;
36 	u32	reserved[4];
37 	u32	reset;
38 };
39 
40 /**
41  * struct pch_gpio_reg_data - The register store data.
42  * @po_reg:	To store contents of PO register.
43  * @pm_reg:	To store contents of PM register.
44  */
45 struct pch_gpio_reg_data {
46 	u32 po_reg;
47 	u32 pm_reg;
48 };
49 
50 /**
51  * struct pch_gpio - GPIO private data structure.
52  * @base:			PCI base address of Memory mapped I/O register.
53  * @reg:			Memory mapped PCH GPIO register list.
54  * @dev:			Pointer to device structure.
55  * @gpio:			Data for GPIO infrastructure.
56  * @pch_gpio_reg:		Memory mapped Register data is saved here
57  *				when suspend.
58  */
59 struct pch_gpio {
60 	void __iomem *base;
61 	struct pch_regs __iomem *reg;
62 	struct device *dev;
63 	struct gpio_chip gpio;
64 	struct pch_gpio_reg_data pch_gpio_reg;
65 	struct mutex lock;
66 };
67 
68 static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
69 {
70 	u32 reg_val;
71 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
72 
73 	mutex_lock(&chip->lock);
74 	reg_val = ioread32(&chip->reg->po);
75 	if (val)
76 		reg_val |= (1 << nr);
77 	else
78 		reg_val &= ~(1 << nr);
79 
80 	iowrite32(reg_val, &chip->reg->po);
81 	mutex_unlock(&chip->lock);
82 }
83 
84 static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
85 {
86 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
87 
88 	return ioread32(&chip->reg->pi) & (1 << nr);
89 }
90 
91 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
92 				     int val)
93 {
94 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
95 	u32 pm;
96 	u32 reg_val;
97 
98 	mutex_lock(&chip->lock);
99 	pm = ioread32(&chip->reg->pm) & PCH_GPIO_ALL_PINS;
100 	pm |= (1 << nr);
101 	iowrite32(pm, &chip->reg->pm);
102 
103 	reg_val = ioread32(&chip->reg->po);
104 	if (val)
105 		reg_val |= (1 << nr);
106 	else
107 		reg_val &= ~(1 << nr);
108 	iowrite32(reg_val, &chip->reg->po);
109 
110 	mutex_unlock(&chip->lock);
111 
112 	return 0;
113 }
114 
115 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
116 {
117 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
118 	u32 pm;
119 
120 	mutex_lock(&chip->lock);
121 	pm = ioread32(&chip->reg->pm) & PCH_GPIO_ALL_PINS; /*bits 0-11*/
122 	pm &= ~(1 << nr);
123 	iowrite32(pm, &chip->reg->pm);
124 	mutex_unlock(&chip->lock);
125 
126 	return 0;
127 }
128 
129 /*
130  * Save register configuration and disable interrupts.
131  */
132 static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
133 {
134 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
135 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
136 }
137 
138 /*
139  * This function restores the register configuration of the GPIO device.
140  */
141 static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
142 {
143 	/* to store contents of PO register */
144 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
145 	/* to store contents of PM register */
146 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
147 }
148 
149 static void pch_gpio_setup(struct pch_gpio *chip)
150 {
151 	struct gpio_chip *gpio = &chip->gpio;
152 
153 	gpio->label = dev_name(chip->dev);
154 	gpio->owner = THIS_MODULE;
155 	gpio->direction_input = pch_gpio_direction_input;
156 	gpio->get = pch_gpio_get;
157 	gpio->direction_output = pch_gpio_direction_output;
158 	gpio->set = pch_gpio_set;
159 	gpio->dbg_show = NULL;
160 	gpio->base = -1;
161 	gpio->ngpio = GPIO_NUM_PINS;
162 	gpio->can_sleep = 0;
163 }
164 
165 static int __devinit pch_gpio_probe(struct pci_dev *pdev,
166 				    const struct pci_device_id *id)
167 {
168 	s32 ret;
169 	struct pch_gpio *chip;
170 
171 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
172 	if (chip == NULL)
173 		return -ENOMEM;
174 
175 	chip->dev = &pdev->dev;
176 	ret = pci_enable_device(pdev);
177 	if (ret) {
178 		dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
179 		goto err_pci_enable;
180 	}
181 
182 	ret = pci_request_regions(pdev, KBUILD_MODNAME);
183 	if (ret) {
184 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
185 		goto err_request_regions;
186 	}
187 
188 	chip->base = pci_iomap(pdev, 1, 0);
189 	if (chip->base == 0) {
190 		dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
191 		ret = -ENOMEM;
192 		goto err_iomap;
193 	}
194 
195 	chip->reg = chip->base;
196 	pci_set_drvdata(pdev, chip);
197 	mutex_init(&chip->lock);
198 	pch_gpio_setup(chip);
199 	ret = gpiochip_add(&chip->gpio);
200 	if (ret) {
201 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
202 		goto err_gpiochip_add;
203 	}
204 
205 	return 0;
206 
207 err_gpiochip_add:
208 	pci_iounmap(pdev, chip->base);
209 
210 err_iomap:
211 	pci_release_regions(pdev);
212 
213 err_request_regions:
214 	pci_disable_device(pdev);
215 
216 err_pci_enable:
217 	kfree(chip);
218 	dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
219 	return ret;
220 }
221 
222 static void __devexit pch_gpio_remove(struct pci_dev *pdev)
223 {
224 	int err;
225 	struct pch_gpio *chip = pci_get_drvdata(pdev);
226 
227 	err = gpiochip_remove(&chip->gpio);
228 	if (err)
229 		dev_err(&pdev->dev, "Failed gpiochip_remove\n");
230 
231 	pci_iounmap(pdev, chip->base);
232 	pci_release_regions(pdev);
233 	pci_disable_device(pdev);
234 	kfree(chip);
235 }
236 
237 #ifdef CONFIG_PM
238 static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
239 {
240 	s32 ret;
241 	struct pch_gpio *chip = pci_get_drvdata(pdev);
242 
243 	pch_gpio_save_reg_conf(chip);
244 	pch_gpio_restore_reg_conf(chip);
245 
246 	ret = pci_save_state(pdev);
247 	if (ret) {
248 		dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
249 		return ret;
250 	}
251 	pci_disable_device(pdev);
252 	pci_set_power_state(pdev, PCI_D0);
253 	ret = pci_enable_wake(pdev, PCI_D0, 1);
254 	if (ret)
255 		dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
256 
257 	return 0;
258 }
259 
260 static int pch_gpio_resume(struct pci_dev *pdev)
261 {
262 	s32 ret;
263 	struct pch_gpio *chip = pci_get_drvdata(pdev);
264 
265 	ret = pci_enable_wake(pdev, PCI_D0, 0);
266 
267 	pci_set_power_state(pdev, PCI_D0);
268 	ret = pci_enable_device(pdev);
269 	if (ret) {
270 		dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
271 		return ret;
272 	}
273 	pci_restore_state(pdev);
274 
275 	iowrite32(0x01, &chip->reg->reset);
276 	iowrite32(0x00, &chip->reg->reset);
277 	pch_gpio_restore_reg_conf(chip);
278 
279 	return 0;
280 }
281 #else
282 #define pch_gpio_suspend NULL
283 #define pch_gpio_resume NULL
284 #endif
285 
286 #define PCI_VENDOR_ID_ROHM             0x10DB
287 static DEFINE_PCI_DEVICE_TABLE(pch_gpio_pcidev_id) = {
288 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
289 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
290 	{ 0, }
291 };
292 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
293 
294 static struct pci_driver pch_gpio_driver = {
295 	.name = "pch_gpio",
296 	.id_table = pch_gpio_pcidev_id,
297 	.probe = pch_gpio_probe,
298 	.remove = __devexit_p(pch_gpio_remove),
299 	.suspend = pch_gpio_suspend,
300 	.resume = pch_gpio_resume
301 };
302 
303 static int __init pch_gpio_pci_init(void)
304 {
305 	return pci_register_driver(&pch_gpio_driver);
306 }
307 module_init(pch_gpio_pci_init);
308 
309 static void __exit pch_gpio_pci_exit(void)
310 {
311 	pci_unregister_driver(&pch_gpio_driver);
312 }
313 module_exit(pch_gpio_pci_exit);
314 
315 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
316 MODULE_LICENSE("GPL");
317