xref: /openbmc/linux/drivers/gpio/gpio-bt8xx.c (revision 79f08d9e)
1 /*
2 
3     bt8xx GPIO abuser
4 
5     Copyright (C) 2008 Michael Buesch <m@bues.ch>
6 
7     Please do _only_ contact the people listed _above_ with issues related to this driver.
8     All the other people listed below are not related to this driver. Their names
9     are only here, because this driver is derived from the bt848 driver.
10 
11 
12     Derived from the bt848 driver:
13 
14     Copyright (C) 1996,97,98 Ralph  Metzler
15 			   & Marcus Metzler
16     (c) 1999-2002 Gerd Knorr
17 
18     some v4l2 code lines are taken from Justin's bttv2 driver which is
19     (c) 2000 Justin Schoeman
20 
21     V4L1 removal from:
22     (c) 2005-2006 Nickolay V. Shmyrev
23 
24     Fixes to be fully V4L2 compliant by
25     (c) 2006 Mauro Carvalho Chehab
26 
27     Cropping and overscan support
28     Copyright (C) 2005, 2006 Michael H. Schimek
29     Sponsored by OPQ Systems AB
30 
31     This program is free software; you can redistribute it and/or modify
32     it under the terms of the GNU General Public License as published by
33     the Free Software Foundation; either version 2 of the License, or
34     (at your option) any later version.
35 
36     This program is distributed in the hope that it will be useful,
37     but WITHOUT ANY WARRANTY; without even the implied warranty of
38     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
39     GNU General Public License for more details.
40 
41     You should have received a copy of the GNU General Public License
42     along with this program; if not, write to the Free Software
43     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
44 */
45 
46 #include <linux/module.h>
47 #include <linux/pci.h>
48 #include <linux/spinlock.h>
49 #include <linux/gpio.h>
50 #include <linux/slab.h>
51 
52 /* Steal the hardware definitions from the bttv driver. */
53 #include "../media/pci/bt8xx/bt848.h"
54 
55 
56 #define BT8XXGPIO_NR_GPIOS		24 /* We have 24 GPIO pins */
57 
58 
59 struct bt8xxgpio {
60 	spinlock_t lock;
61 
62 	void __iomem *mmio;
63 	struct pci_dev *pdev;
64 	struct gpio_chip gpio;
65 
66 #ifdef CONFIG_PM
67 	u32 saved_outen;
68 	u32 saved_data;
69 #endif
70 };
71 
72 #define bgwrite(dat, adr)	writel((dat), bg->mmio+(adr))
73 #define bgread(adr)		readl(bg->mmio+(adr))
74 
75 
76 static int modparam_gpiobase = -1/* dynamic */;
77 module_param_named(gpiobase, modparam_gpiobase, int, 0444);
78 MODULE_PARM_DESC(gpiobase, "The GPIO number base. -1 means dynamic, which is the default.");
79 
80 
81 static int bt8xxgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
82 {
83 	struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
84 	unsigned long flags;
85 	u32 outen, data;
86 
87 	spin_lock_irqsave(&bg->lock, flags);
88 
89 	data = bgread(BT848_GPIO_DATA);
90 	data &= ~(1 << nr);
91 	bgwrite(data, BT848_GPIO_DATA);
92 
93 	outen = bgread(BT848_GPIO_OUT_EN);
94 	outen &= ~(1 << nr);
95 	bgwrite(outen, BT848_GPIO_OUT_EN);
96 
97 	spin_unlock_irqrestore(&bg->lock, flags);
98 
99 	return 0;
100 }
101 
102 static int bt8xxgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
103 {
104 	struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
105 	unsigned long flags;
106 	u32 val;
107 
108 	spin_lock_irqsave(&bg->lock, flags);
109 	val = bgread(BT848_GPIO_DATA);
110 	spin_unlock_irqrestore(&bg->lock, flags);
111 
112 	return !!(val & (1 << nr));
113 }
114 
115 static int bt8xxgpio_gpio_direction_output(struct gpio_chip *gpio,
116 					unsigned nr, int val)
117 {
118 	struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
119 	unsigned long flags;
120 	u32 outen, data;
121 
122 	spin_lock_irqsave(&bg->lock, flags);
123 
124 	outen = bgread(BT848_GPIO_OUT_EN);
125 	outen |= (1 << nr);
126 	bgwrite(outen, BT848_GPIO_OUT_EN);
127 
128 	data = bgread(BT848_GPIO_DATA);
129 	if (val)
130 		data |= (1 << nr);
131 	else
132 		data &= ~(1 << nr);
133 	bgwrite(data, BT848_GPIO_DATA);
134 
135 	spin_unlock_irqrestore(&bg->lock, flags);
136 
137 	return 0;
138 }
139 
140 static void bt8xxgpio_gpio_set(struct gpio_chip *gpio,
141 			    unsigned nr, int val)
142 {
143 	struct bt8xxgpio *bg = container_of(gpio, struct bt8xxgpio, gpio);
144 	unsigned long flags;
145 	u32 data;
146 
147 	spin_lock_irqsave(&bg->lock, flags);
148 
149 	data = bgread(BT848_GPIO_DATA);
150 	if (val)
151 		data |= (1 << nr);
152 	else
153 		data &= ~(1 << nr);
154 	bgwrite(data, BT848_GPIO_DATA);
155 
156 	spin_unlock_irqrestore(&bg->lock, flags);
157 }
158 
159 static void bt8xxgpio_gpio_setup(struct bt8xxgpio *bg)
160 {
161 	struct gpio_chip *c = &bg->gpio;
162 
163 	c->label = dev_name(&bg->pdev->dev);
164 	c->owner = THIS_MODULE;
165 	c->direction_input = bt8xxgpio_gpio_direction_input;
166 	c->get = bt8xxgpio_gpio_get;
167 	c->direction_output = bt8xxgpio_gpio_direction_output;
168 	c->set = bt8xxgpio_gpio_set;
169 	c->dbg_show = NULL;
170 	c->base = modparam_gpiobase;
171 	c->ngpio = BT8XXGPIO_NR_GPIOS;
172 	c->can_sleep = 0;
173 }
174 
175 static int bt8xxgpio_probe(struct pci_dev *dev,
176 			const struct pci_device_id *pci_id)
177 {
178 	struct bt8xxgpio *bg;
179 	int err;
180 
181 	bg = kzalloc(sizeof(*bg), GFP_KERNEL);
182 	if (!bg)
183 		return -ENOMEM;
184 
185 	bg->pdev = dev;
186 	spin_lock_init(&bg->lock);
187 
188 	err = pci_enable_device(dev);
189 	if (err) {
190 		printk(KERN_ERR "bt8xxgpio: Can't enable device.\n");
191 		goto err_freebg;
192 	}
193 	if (!request_mem_region(pci_resource_start(dev, 0),
194 				pci_resource_len(dev, 0),
195 				"bt8xxgpio")) {
196 		printk(KERN_WARNING "bt8xxgpio: Can't request iomem (0x%llx).\n",
197 		       (unsigned long long)pci_resource_start(dev, 0));
198 		err = -EBUSY;
199 		goto err_disable;
200 	}
201 	pci_set_master(dev);
202 	pci_set_drvdata(dev, bg);
203 
204 	bg->mmio = ioremap(pci_resource_start(dev, 0), 0x1000);
205 	if (!bg->mmio) {
206 		printk(KERN_ERR "bt8xxgpio: ioremap() failed\n");
207 		err = -EIO;
208 		goto err_release_mem;
209 	}
210 
211 	/* Disable interrupts */
212 	bgwrite(0, BT848_INT_MASK);
213 
214 	/* gpio init */
215 	bgwrite(0, BT848_GPIO_DMA_CTL);
216 	bgwrite(0, BT848_GPIO_REG_INP);
217 	bgwrite(0, BT848_GPIO_OUT_EN);
218 
219 	bt8xxgpio_gpio_setup(bg);
220 	err = gpiochip_add(&bg->gpio);
221 	if (err) {
222 		printk(KERN_ERR "bt8xxgpio: Failed to register GPIOs\n");
223 		goto err_release_mem;
224 	}
225 
226 	return 0;
227 
228 err_release_mem:
229 	release_mem_region(pci_resource_start(dev, 0),
230 			   pci_resource_len(dev, 0));
231 err_disable:
232 	pci_disable_device(dev);
233 err_freebg:
234 	kfree(bg);
235 
236 	return err;
237 }
238 
239 static void bt8xxgpio_remove(struct pci_dev *pdev)
240 {
241 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
242 
243 	gpiochip_remove(&bg->gpio);
244 
245 	bgwrite(0, BT848_INT_MASK);
246 	bgwrite(~0x0, BT848_INT_STAT);
247 	bgwrite(0x0, BT848_GPIO_OUT_EN);
248 
249 	iounmap(bg->mmio);
250 	release_mem_region(pci_resource_start(pdev, 0),
251 			   pci_resource_len(pdev, 0));
252 	pci_disable_device(pdev);
253 
254 	kfree(bg);
255 }
256 
257 #ifdef CONFIG_PM
258 static int bt8xxgpio_suspend(struct pci_dev *pdev, pm_message_t state)
259 {
260 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
261 	unsigned long flags;
262 
263 	spin_lock_irqsave(&bg->lock, flags);
264 
265 	bg->saved_outen = bgread(BT848_GPIO_OUT_EN);
266 	bg->saved_data = bgread(BT848_GPIO_DATA);
267 
268 	bgwrite(0, BT848_INT_MASK);
269 	bgwrite(~0x0, BT848_INT_STAT);
270 	bgwrite(0x0, BT848_GPIO_OUT_EN);
271 
272 	spin_unlock_irqrestore(&bg->lock, flags);
273 
274 	pci_save_state(pdev);
275 	pci_disable_device(pdev);
276 	pci_set_power_state(pdev, pci_choose_state(pdev, state));
277 
278 	return 0;
279 }
280 
281 static int bt8xxgpio_resume(struct pci_dev *pdev)
282 {
283 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
284 	unsigned long flags;
285 	int err;
286 
287 	pci_set_power_state(pdev, PCI_D0);
288 	err = pci_enable_device(pdev);
289 	if (err)
290 		return err;
291 	pci_restore_state(pdev);
292 
293 	spin_lock_irqsave(&bg->lock, flags);
294 
295 	bgwrite(0, BT848_INT_MASK);
296 	bgwrite(0, BT848_GPIO_DMA_CTL);
297 	bgwrite(0, BT848_GPIO_REG_INP);
298 	bgwrite(bg->saved_outen, BT848_GPIO_OUT_EN);
299 	bgwrite(bg->saved_data & bg->saved_outen,
300 		BT848_GPIO_DATA);
301 
302 	spin_unlock_irqrestore(&bg->lock, flags);
303 
304 	return 0;
305 }
306 #else
307 #define bt8xxgpio_suspend NULL
308 #define bt8xxgpio_resume NULL
309 #endif /* CONFIG_PM */
310 
311 static DEFINE_PCI_DEVICE_TABLE(bt8xxgpio_pci_tbl) = {
312 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT848) },
313 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT849) },
314 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT878) },
315 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT879) },
316 	{ 0, },
317 };
318 MODULE_DEVICE_TABLE(pci, bt8xxgpio_pci_tbl);
319 
320 static struct pci_driver bt8xxgpio_pci_driver = {
321 	.name		= "bt8xxgpio",
322 	.id_table	= bt8xxgpio_pci_tbl,
323 	.probe		= bt8xxgpio_probe,
324 	.remove		= bt8xxgpio_remove,
325 	.suspend	= bt8xxgpio_suspend,
326 	.resume		= bt8xxgpio_resume,
327 };
328 
329 module_pci_driver(bt8xxgpio_pci_driver);
330 
331 MODULE_LICENSE("GPL");
332 MODULE_AUTHOR("Michael Buesch");
333 MODULE_DESCRIPTION("Abuse a BT8xx framegrabber card as generic GPIO card");
334