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authorMichael Buesch <mb@bu3sch.de>2008-07-25 04:46:10 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2008-07-25 13:53:30 -0400
commitff1d5c2f0268f4e32103536e2e65480b5b7b6530 (patch)
tree3f5e538b85c35eb73db07fb7a57dc8edc46968a4 /drivers/gpio
parent8f1cc3b10e6ee0c5c7c8ed27f8771c4f252b4862 (diff)
gpio: add bt8xxgpio driver
This adds the bt8xxgpio driver. The purpose of the bt8xxgpio driver is to export all of the 24 GPIO pins available on Brooktree 8xx chips to the kernel GPIO infrastructure. This makes it possible to use a physically modified BT8xx card as cheap digital GPIO card. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: David Brownell <david-b@pacbell.net> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r--drivers/gpio/Kconfig18
-rw-r--r--drivers/gpio/Makefile1
-rw-r--r--drivers/gpio/bt8xxgpio.c348
3 files changed, 367 insertions, 0 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 6ec0e35b98e3..de202dbe5300 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -83,6 +83,24 @@ config GPIO_PCF857X
83 This driver provides an in-kernel interface to those GPIOs using 83 This driver provides an in-kernel interface to those GPIOs using
84 platform-neutral GPIO calls. 84 platform-neutral GPIO calls.
85 85
86comment "PCI GPIO expanders:"
87
88config GPIO_BT8XX
89 tristate "BT8XX GPIO abuser"
90 depends on PCI && VIDEO_BT848=n
91 help
92 The BT8xx frame grabber chip has 24 GPIO pins than can be abused
93 as a cheap PCI GPIO card.
94
95 This chip can be found on Miro, Hauppauge and STB TV-cards.
96
97 The card needs to be physically altered for using it as a
98 GPIO card. For more information on how to build a GPIO card
99 from a BT8xx TV card, see the documentation file at
100 Documentation/bt8xxgpio.txt
101
102 If unsure, say N.
103
86comment "SPI GPIO expanders:" 104comment "SPI GPIO expanders:"
87 105
88config GPIO_MAX7301 106config GPIO_MAX7301
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 16e796dc5410..eeb2f2b20282 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -8,3 +8,4 @@ obj-$(CONFIG_GPIO_MAX7301) += max7301.o
8obj-$(CONFIG_GPIO_MCP23S08) += mcp23s08.o 8obj-$(CONFIG_GPIO_MCP23S08) += mcp23s08.o
9obj-$(CONFIG_GPIO_PCA953X) += pca953x.o 9obj-$(CONFIG_GPIO_PCA953X) += pca953x.o
10obj-$(CONFIG_GPIO_PCF857X) += pcf857x.o 10obj-$(CONFIG_GPIO_PCF857X) += pcf857x.o
11obj-$(CONFIG_GPIO_BT8XX) += bt8xxgpio.o
diff --git a/drivers/gpio/bt8xxgpio.c b/drivers/gpio/bt8xxgpio.c
new file mode 100644
index 000000000000..7a1168249dd5
--- /dev/null
+++ b/drivers/gpio/bt8xxgpio.c
@@ -0,0 +1,348 @@
1/*
2
3 bt8xx GPIO abuser
4
5 Copyright (C) 2008 Michael Buesch <mb@bu3sch.de>
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
50#include <asm/gpio.h>
51
52/* Steal the hardware definitions from the bttv driver. */
53#include "../media/video/bt8xx/bt848.h"
54
55
56#define BT8XXGPIO_NR_GPIOS 24 /* We have 24 GPIO pins */
57
58
59struct 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
76static int modparam_gpiobase = -1/* dynamic */;
77module_param_named(gpiobase, modparam_gpiobase, int, 0444);
78MODULE_PARM_DESC(gpiobase, "The GPIO number base. -1 means dynamic, which is the default.");
79
80
81static 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
102static 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
115static 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
140static 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
159static void bt8xxgpio_gpio_setup(struct bt8xxgpio *bg)
160{
161 struct gpio_chip *c = &bg->gpio;
162
163 c->label = bg->pdev->dev.bus_id;
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
175static 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 printk(KERN_INFO "bt8xxgpio: Abusing BT8xx card for GPIOs %d to %d\n",
227 bg->gpio.base, bg->gpio.base + BT8XXGPIO_NR_GPIOS - 1);
228
229 return 0;
230
231err_release_mem:
232 release_mem_region(pci_resource_start(dev, 0),
233 pci_resource_len(dev, 0));
234 pci_set_drvdata(dev, NULL);
235err_disable:
236 pci_disable_device(dev);
237err_freebg:
238 kfree(bg);
239
240 return err;
241}
242
243static void bt8xxgpio_remove(struct pci_dev *pdev)
244{
245 struct bt8xxgpio *bg = pci_get_drvdata(pdev);
246
247 gpiochip_remove(&bg->gpio);
248
249 bgwrite(0, BT848_INT_MASK);
250 bgwrite(~0x0, BT848_INT_STAT);
251 bgwrite(0x0, BT848_GPIO_OUT_EN);
252
253 iounmap(bg->mmio);
254 release_mem_region(pci_resource_start(pdev, 0),
255 pci_resource_len(pdev, 0));
256 pci_disable_device(pdev);
257
258 pci_set_drvdata(pdev, NULL);
259 kfree(bg);
260}
261
262#ifdef CONFIG_PM
263static int bt8xxgpio_suspend(struct pci_dev *pdev, pm_message_t state)
264{
265 struct bt8xxgpio *bg = pci_get_drvdata(pdev);
266 unsigned long flags;
267
268 spin_lock_irqsave(&bg->lock, flags);
269
270 bg->saved_outen = bgread(BT848_GPIO_OUT_EN);
271 bg->saved_data = bgread(BT848_GPIO_DATA);
272
273 bgwrite(0, BT848_INT_MASK);
274 bgwrite(~0x0, BT848_INT_STAT);
275 bgwrite(0x0, BT848_GPIO_OUT_EN);
276
277 spin_unlock_irqrestore(&bg->lock, flags);
278
279 pci_save_state(pdev);
280 pci_disable_device(pdev);
281 pci_set_power_state(pdev, pci_choose_state(pdev, state));
282
283 return 0;
284}
285
286static int bt8xxgpio_resume(struct pci_dev *pdev)
287{
288 struct bt8xxgpio *bg = pci_get_drvdata(pdev);
289 unsigned long flags;
290 int err;
291
292 pci_set_power_state(pdev, 0);
293 err = pci_enable_device(pdev);
294 if (err)
295 return err;
296 pci_restore_state(pdev);
297
298 spin_lock_irqsave(&bg->lock, flags);
299
300 bgwrite(0, BT848_INT_MASK);
301 bgwrite(0, BT848_GPIO_DMA_CTL);
302 bgwrite(0, BT848_GPIO_REG_INP);
303 bgwrite(bg->saved_outen, BT848_GPIO_OUT_EN);
304 bgwrite(bg->saved_data & bg->saved_outen,
305 BT848_GPIO_DATA);
306
307 spin_unlock_irqrestore(&bg->lock, flags);
308
309 return 0;
310}
311#else
312#define bt8xxgpio_suspend NULL
313#define bt8xxgpio_resume NULL
314#endif /* CONFIG_PM */
315
316static struct pci_device_id bt8xxgpio_pci_tbl[] = {
317 { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT848) },
318 { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT849) },
319 { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT878) },
320 { PCI_DEVICE(PCI_VENDOR_ID_BROOKTREE, PCI_DEVICE_ID_BT879) },
321 { 0, },
322};
323MODULE_DEVICE_TABLE(pci, bt8xxgpio_pci_tbl);
324
325static struct pci_driver bt8xxgpio_pci_driver = {
326 .name = "bt8xxgpio",
327 .id_table = bt8xxgpio_pci_tbl,
328 .probe = bt8xxgpio_probe,
329 .remove = bt8xxgpio_remove,
330 .suspend = bt8xxgpio_suspend,
331 .resume = bt8xxgpio_resume,
332};
333
334static int bt8xxgpio_init(void)
335{
336 return pci_register_driver(&bt8xxgpio_pci_driver);
337}
338module_init(bt8xxgpio_init)
339
340static void bt8xxgpio_exit(void)
341{
342 pci_unregister_driver(&bt8xxgpio_pci_driver);
343}
344module_exit(bt8xxgpio_exit)
345
346MODULE_LICENSE("GPL");
347MODULE_AUTHOR("Michael Buesch");
348MODULE_DESCRIPTION("Abuse a BT8xx framegrabber card as generic GPIO card");