xref: /openbmc/linux/drivers/gpio/gpio-bt8xx.c (revision 020c5260)
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 = gpiochip_get_data(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 = gpiochip_get_data(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 = gpiochip_get_data(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 = gpiochip_get_data(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 = false;
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 = devm_kzalloc(&dev->dev, sizeof(struct bt8xxgpio), 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 		return err;
192 	}
193 	if (!devm_request_mem_region(&dev->dev, 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 = devm_ioremap(&dev->dev, pci_resource_start(dev, 0), 0x1000);
205 	if (!bg->mmio) {
206 		printk(KERN_ERR "bt8xxgpio: ioremap() failed\n");
207 		err = -EIO;
208 		goto err_disable;
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_data(&bg->gpio, bg);
221 	if (err) {
222 		printk(KERN_ERR "bt8xxgpio: Failed to register GPIOs\n");
223 		goto err_disable;
224 	}
225 
226 	return 0;
227 
228 err_disable:
229 	pci_disable_device(dev);
230 
231 	return err;
232 }
233 
234 static void bt8xxgpio_remove(struct pci_dev *pdev)
235 {
236 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
237 
238 	gpiochip_remove(&bg->gpio);
239 
240 	bgwrite(0, BT848_INT_MASK);
241 	bgwrite(~0x0, BT848_INT_STAT);
242 	bgwrite(0x0, BT848_GPIO_OUT_EN);
243 
244 	pci_disable_device(pdev);
245 }
246 
247 #ifdef CONFIG_PM
248 static int bt8xxgpio_suspend(struct pci_dev *pdev, pm_message_t state)
249 {
250 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
251 	unsigned long flags;
252 
253 	spin_lock_irqsave(&bg->lock, flags);
254 
255 	bg->saved_outen = bgread(BT848_GPIO_OUT_EN);
256 	bg->saved_data = bgread(BT848_GPIO_DATA);
257 
258 	bgwrite(0, BT848_INT_MASK);
259 	bgwrite(~0x0, BT848_INT_STAT);
260 	bgwrite(0x0, BT848_GPIO_OUT_EN);
261 
262 	spin_unlock_irqrestore(&bg->lock, flags);
263 
264 	pci_save_state(pdev);
265 	pci_disable_device(pdev);
266 	pci_set_power_state(pdev, pci_choose_state(pdev, state));
267 
268 	return 0;
269 }
270 
271 static int bt8xxgpio_resume(struct pci_dev *pdev)
272 {
273 	struct bt8xxgpio *bg = pci_get_drvdata(pdev);
274 	unsigned long flags;
275 	int err;
276 
277 	pci_set_power_state(pdev, PCI_D0);
278 	err = pci_enable_device(pdev);
279 	if (err)
280 		return err;
281 	pci_restore_state(pdev);
282 
283 	spin_lock_irqsave(&bg->lock, flags);
284 
285 	bgwrite(0, BT848_INT_MASK);
286 	bgwrite(0, BT848_GPIO_DMA_CTL);
287 	bgwrite(0, BT848_GPIO_REG_INP);
288 	bgwrite(bg->saved_outen, BT848_GPIO_OUT_EN);
289 	bgwrite(bg->saved_data & bg->saved_outen,
290 		BT848_GPIO_DATA);
291 
292 	spin_unlock_irqrestore(&bg->lock, flags);
293 
294 	return 0;
295 }
296 #else
297 #define bt8xxgpio_suspend NULL
298 #define bt8xxgpio_resume NULL
299 #endif /* CONFIG_PM */
300 
301 static const struct pci_device_id bt8xxgpio_pci_tbl[] = {
302 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT848) },
303 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT849) },
304 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT878) },
305 	{ PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT879) },
306 	{ 0, },
307 };
308 MODULE_DEVICE_TABLE(pci, bt8xxgpio_pci_tbl);
309 
310 static struct pci_driver bt8xxgpio_pci_driver = {
311 	.name		= "bt8xxgpio",
312 	.id_table	= bt8xxgpio_pci_tbl,
313 	.probe		= bt8xxgpio_probe,
314 	.remove		= bt8xxgpio_remove,
315 	.suspend	= bt8xxgpio_suspend,
316 	.resume		= bt8xxgpio_resume,
317 };
318 
319 module_pci_driver(bt8xxgpio_pci_driver);
320 
321 MODULE_LICENSE("GPL");
322 MODULE_AUTHOR("Michael Buesch");
323 MODULE_DESCRIPTION("Abuse a BT8xx framegrabber card as generic GPIO card");
324