xref: /linux/drivers/gpio/gpio-pch.c (revision d568a6814fde60f5ab6b0c29b6261ff1899da443)
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  * @spinlock:		Used for register access protection in
59  *				interrupt context pch_irq_mask,
60  *				pch_irq_unmask and pch_irq_type;
61  */
62 struct pch_gpio {
63 	void __iomem *base;
64 	struct pch_regs __iomem *reg;
65 	struct device *dev;
66 	struct gpio_chip gpio;
67 	struct pch_gpio_reg_data pch_gpio_reg;
68 	struct mutex lock;
69 	spinlock_t spinlock;
70 };
71 
72 static void pch_gpio_set(struct gpio_chip *gpio, unsigned nr, int val)
73 {
74 	u32 reg_val;
75 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
76 
77 	mutex_lock(&chip->lock);
78 	reg_val = ioread32(&chip->reg->po);
79 	if (val)
80 		reg_val |= (1 << nr);
81 	else
82 		reg_val &= ~(1 << nr);
83 
84 	iowrite32(reg_val, &chip->reg->po);
85 	mutex_unlock(&chip->lock);
86 }
87 
88 static int pch_gpio_get(struct gpio_chip *gpio, unsigned nr)
89 {
90 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
91 
92 	return ioread32(&chip->reg->pi) & (1 << nr);
93 }
94 
95 static int pch_gpio_direction_output(struct gpio_chip *gpio, unsigned nr,
96 				     int val)
97 {
98 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
99 	u32 pm;
100 	u32 reg_val;
101 
102 	mutex_lock(&chip->lock);
103 	pm = ioread32(&chip->reg->pm) & PCH_GPIO_ALL_PINS;
104 	pm |= (1 << nr);
105 	iowrite32(pm, &chip->reg->pm);
106 
107 	reg_val = ioread32(&chip->reg->po);
108 	if (val)
109 		reg_val |= (1 << nr);
110 	else
111 		reg_val &= ~(1 << nr);
112 	iowrite32(reg_val, &chip->reg->po);
113 
114 	mutex_unlock(&chip->lock);
115 
116 	return 0;
117 }
118 
119 static int pch_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
120 {
121 	struct pch_gpio *chip =	container_of(gpio, struct pch_gpio, gpio);
122 	u32 pm;
123 
124 	mutex_lock(&chip->lock);
125 	pm = ioread32(&chip->reg->pm) & PCH_GPIO_ALL_PINS; /*bits 0-11*/
126 	pm &= ~(1 << nr);
127 	iowrite32(pm, &chip->reg->pm);
128 	mutex_unlock(&chip->lock);
129 
130 	return 0;
131 }
132 
133 /*
134  * Save register configuration and disable interrupts.
135  */
136 static void pch_gpio_save_reg_conf(struct pch_gpio *chip)
137 {
138 	chip->pch_gpio_reg.po_reg = ioread32(&chip->reg->po);
139 	chip->pch_gpio_reg.pm_reg = ioread32(&chip->reg->pm);
140 }
141 
142 /*
143  * This function restores the register configuration of the GPIO device.
144  */
145 static void pch_gpio_restore_reg_conf(struct pch_gpio *chip)
146 {
147 	/* to store contents of PO register */
148 	iowrite32(chip->pch_gpio_reg.po_reg, &chip->reg->po);
149 	/* to store contents of PM register */
150 	iowrite32(chip->pch_gpio_reg.pm_reg, &chip->reg->pm);
151 }
152 
153 static void pch_gpio_setup(struct pch_gpio *chip)
154 {
155 	struct gpio_chip *gpio = &chip->gpio;
156 
157 	gpio->label = dev_name(chip->dev);
158 	gpio->owner = THIS_MODULE;
159 	gpio->direction_input = pch_gpio_direction_input;
160 	gpio->get = pch_gpio_get;
161 	gpio->direction_output = pch_gpio_direction_output;
162 	gpio->set = pch_gpio_set;
163 	gpio->dbg_show = NULL;
164 	gpio->base = -1;
165 	gpio->ngpio = GPIO_NUM_PINS;
166 	gpio->can_sleep = 0;
167 }
168 
169 static int __devinit pch_gpio_probe(struct pci_dev *pdev,
170 				    const struct pci_device_id *id)
171 {
172 	s32 ret;
173 	struct pch_gpio *chip;
174 
175 	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
176 	if (chip == NULL)
177 		return -ENOMEM;
178 
179 	chip->dev = &pdev->dev;
180 	ret = pci_enable_device(pdev);
181 	if (ret) {
182 		dev_err(&pdev->dev, "%s : pci_enable_device FAILED", __func__);
183 		goto err_pci_enable;
184 	}
185 
186 	ret = pci_request_regions(pdev, KBUILD_MODNAME);
187 	if (ret) {
188 		dev_err(&pdev->dev, "pci_request_regions FAILED-%d", ret);
189 		goto err_request_regions;
190 	}
191 
192 	chip->base = pci_iomap(pdev, 1, 0);
193 	if (chip->base == 0) {
194 		dev_err(&pdev->dev, "%s : pci_iomap FAILED", __func__);
195 		ret = -ENOMEM;
196 		goto err_iomap;
197 	}
198 
199 	chip->reg = chip->base;
200 	pci_set_drvdata(pdev, chip);
201 	mutex_init(&chip->lock);
202 	pch_gpio_setup(chip);
203 	ret = gpiochip_add(&chip->gpio);
204 	if (ret) {
205 		dev_err(&pdev->dev, "PCH gpio: Failed to register GPIO\n");
206 		goto err_gpiochip_add;
207 	}
208 
209 	return 0;
210 
211 err_gpiochip_add:
212 	pci_iounmap(pdev, chip->base);
213 
214 err_iomap:
215 	pci_release_regions(pdev);
216 
217 err_request_regions:
218 	pci_disable_device(pdev);
219 
220 err_pci_enable:
221 	kfree(chip);
222 	dev_err(&pdev->dev, "%s Failed returns %d\n", __func__, ret);
223 	return ret;
224 }
225 
226 static void __devexit pch_gpio_remove(struct pci_dev *pdev)
227 {
228 	int err;
229 	struct pch_gpio *chip = pci_get_drvdata(pdev);
230 
231 	err = gpiochip_remove(&chip->gpio);
232 	if (err)
233 		dev_err(&pdev->dev, "Failed gpiochip_remove\n");
234 
235 	pci_iounmap(pdev, chip->base);
236 	pci_release_regions(pdev);
237 	pci_disable_device(pdev);
238 	kfree(chip);
239 }
240 
241 #ifdef CONFIG_PM
242 static int pch_gpio_suspend(struct pci_dev *pdev, pm_message_t state)
243 {
244 	s32 ret;
245 	struct pch_gpio *chip = pci_get_drvdata(pdev);
246 	unsigned long flags;
247 
248 	spin_lock_irqsave(&chip->spinlock, flags);
249 	pch_gpio_save_reg_conf(chip);
250 	spin_unlock_irqrestore(&chip->spinlock, flags);
251 
252 	ret = pci_save_state(pdev);
253 	if (ret) {
254 		dev_err(&pdev->dev, "pci_save_state Failed-%d\n", ret);
255 		return ret;
256 	}
257 	pci_disable_device(pdev);
258 	pci_set_power_state(pdev, PCI_D0);
259 	ret = pci_enable_wake(pdev, PCI_D0, 1);
260 	if (ret)
261 		dev_err(&pdev->dev, "pci_enable_wake Failed -%d\n", ret);
262 
263 	return 0;
264 }
265 
266 static int pch_gpio_resume(struct pci_dev *pdev)
267 {
268 	s32 ret;
269 	struct pch_gpio *chip = pci_get_drvdata(pdev);
270 	unsigned long flags;
271 
272 	ret = pci_enable_wake(pdev, PCI_D0, 0);
273 
274 	pci_set_power_state(pdev, PCI_D0);
275 	ret = pci_enable_device(pdev);
276 	if (ret) {
277 		dev_err(&pdev->dev, "pci_enable_device Failed-%d ", ret);
278 		return ret;
279 	}
280 	pci_restore_state(pdev);
281 
282 	spin_lock_irqsave(&chip->spinlock, flags);
283 	iowrite32(0x01, &chip->reg->reset);
284 	iowrite32(0x00, &chip->reg->reset);
285 	pch_gpio_restore_reg_conf(chip);
286 	spin_unlock_irqrestore(&chip->spinlock, flags);
287 
288 	return 0;
289 }
290 #else
291 #define pch_gpio_suspend NULL
292 #define pch_gpio_resume NULL
293 #endif
294 
295 #define PCI_VENDOR_ID_ROHM             0x10DB
296 static DEFINE_PCI_DEVICE_TABLE(pch_gpio_pcidev_id) = {
297 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x8803) },
298 	{ PCI_DEVICE(PCI_VENDOR_ID_ROHM, 0x8014) },
299 	{ 0, }
300 };
301 MODULE_DEVICE_TABLE(pci, pch_gpio_pcidev_id);
302 
303 static struct pci_driver pch_gpio_driver = {
304 	.name = "pch_gpio",
305 	.id_table = pch_gpio_pcidev_id,
306 	.probe = pch_gpio_probe,
307 	.remove = __devexit_p(pch_gpio_remove),
308 	.suspend = pch_gpio_suspend,
309 	.resume = pch_gpio_resume
310 };
311 
312 static int __init pch_gpio_pci_init(void)
313 {
314 	return pci_register_driver(&pch_gpio_driver);
315 }
316 module_init(pch_gpio_pci_init);
317 
318 static void __exit pch_gpio_pci_exit(void)
319 {
320 	pci_unregister_driver(&pch_gpio_driver);
321 }
322 module_exit(pch_gpio_pci_exit);
323 
324 MODULE_DESCRIPTION("PCH GPIO PCI Driver");
325 MODULE_LICENSE("GPL");
326