xref: /linux/drivers/gpio/gpio-sodaville.c (revision 06eb4eafbdc0796d741d139a44f1253278da8611)
1 /*
2  *  GPIO interface for Intel Sodaville SoCs.
3  *
4  *  Copyright (c) 2010, 2011 Intel Corporation
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License 2 as published
8  *  by the Free Software Foundation.
9  *
10  */
11 
12 #include <linux/errno.h>
13 #include <linux/gpio.h>
14 #include <linux/init.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 #include <linux/interrupt.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/pci.h>
21 #include <linux/platform_device.h>
22 #include <linux/of_irq.h>
23 #include <linux/basic_mmio_gpio.h>
24 
25 #define DRV_NAME		"sdv_gpio"
26 #define SDV_NUM_PUB_GPIOS	12
27 #define PCI_DEVICE_ID_SDV_GPIO	0x2e67
28 #define GPIO_BAR		0
29 
30 #define GPOUTR		0x00
31 #define GPOER		0x04
32 #define GPINR		0x08
33 
34 #define GPSTR		0x0c
35 #define GPIT1R0		0x10
36 #define GPIO_INT	0x14
37 #define GPIT1R1		0x18
38 
39 #define GPMUXCTL	0x1c
40 
41 struct sdv_gpio_chip_data {
42 	int irq_base;
43 	void __iomem *gpio_pub_base;
44 	struct irq_domain id;
45 	struct irq_chip_generic *gc;
46 	struct bgpio_chip bgpio;
47 };
48 
49 static int sdv_gpio_pub_set_type(struct irq_data *d, unsigned int type)
50 {
51 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
52 	struct sdv_gpio_chip_data *sd = gc->private;
53 	void __iomem *type_reg;
54 	u32 irq_offs = d->irq - sd->irq_base;
55 	u32 reg;
56 
57 	if (irq_offs < 8)
58 		type_reg = sd->gpio_pub_base + GPIT1R0;
59 	else
60 		type_reg = sd->gpio_pub_base + GPIT1R1;
61 
62 	reg = readl(type_reg);
63 
64 	switch (type) {
65 	case IRQ_TYPE_LEVEL_HIGH:
66 		reg &= ~BIT(4 * (irq_offs % 8));
67 		break;
68 
69 	case IRQ_TYPE_LEVEL_LOW:
70 		reg |= BIT(4 * (irq_offs % 8));
71 		break;
72 
73 	default:
74 		return -EINVAL;
75 	}
76 
77 	writel(reg, type_reg);
78 	return 0;
79 }
80 
81 static irqreturn_t sdv_gpio_pub_irq_handler(int irq, void *data)
82 {
83 	struct sdv_gpio_chip_data *sd = data;
84 	u32 irq_stat = readl(sd->gpio_pub_base + GPSTR);
85 
86 	irq_stat &= readl(sd->gpio_pub_base + GPIO_INT);
87 	if (!irq_stat)
88 		return IRQ_NONE;
89 
90 	while (irq_stat) {
91 		u32 irq_bit = __fls(irq_stat);
92 
93 		irq_stat &= ~BIT(irq_bit);
94 		generic_handle_irq(sd->irq_base + irq_bit);
95 	}
96 
97 	return IRQ_HANDLED;
98 }
99 
100 static int sdv_xlate(struct irq_domain *h, struct device_node *node,
101 		const u32 *intspec, u32 intsize, irq_hw_number_t *out_hwirq,
102 		u32 *out_type)
103 {
104 	u32 line, type;
105 
106 	if (node != h->of_node)
107 		return -EINVAL;
108 
109 	if (intsize < 2)
110 		return -EINVAL;
111 
112 	line = *intspec;
113 	*out_hwirq = line;
114 
115 	intspec++;
116 	type = *intspec;
117 
118 	switch (type) {
119 	case IRQ_TYPE_LEVEL_LOW:
120 	case IRQ_TYPE_LEVEL_HIGH:
121 		*out_type = type;
122 		break;
123 	default:
124 		return -EINVAL;
125 	}
126 	return 0;
127 }
128 
129 static struct irq_domain_ops irq_domain_sdv_ops = {
130 	.dt_translate	= sdv_xlate,
131 };
132 
133 static __devinit int sdv_register_irqsupport(struct sdv_gpio_chip_data *sd,
134 		struct pci_dev *pdev)
135 {
136 	struct irq_chip_type *ct;
137 	int ret;
138 
139 	sd->irq_base = irq_alloc_descs(-1, 0, SDV_NUM_PUB_GPIOS, -1);
140 	if (sd->irq_base < 0)
141 		return sd->irq_base;
142 
143 	/* mask + ACK all interrupt sources */
144 	writel(0, sd->gpio_pub_base + GPIO_INT);
145 	writel((1 << 11) - 1, sd->gpio_pub_base + GPSTR);
146 
147 	ret = request_irq(pdev->irq, sdv_gpio_pub_irq_handler, IRQF_SHARED,
148 			"sdv_gpio", sd);
149 	if (ret)
150 		goto out_free_desc;
151 
152 	sd->id.irq_base = sd->irq_base;
153 	sd->id.of_node = of_node_get(pdev->dev.of_node);
154 	sd->id.ops = &irq_domain_sdv_ops;
155 
156 	/*
157 	 * This gpio irq controller latches level irqs. Testing shows that if
158 	 * we unmask & ACK the IRQ before the source of the interrupt is gone
159 	 * then the interrupt is active again.
160 	 */
161 	sd->gc = irq_alloc_generic_chip("sdv-gpio", 1, sd->irq_base,
162 			sd->gpio_pub_base, handle_fasteoi_irq);
163 	if (!sd->gc) {
164 		ret = -ENOMEM;
165 		goto out_free_irq;
166 	}
167 
168 	sd->gc->private = sd;
169 	ct = sd->gc->chip_types;
170 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
171 	ct->regs.eoi = GPSTR;
172 	ct->regs.mask = GPIO_INT;
173 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
174 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
175 	ct->chip.irq_eoi = irq_gc_eoi;
176 	ct->chip.irq_set_type = sdv_gpio_pub_set_type;
177 
178 	irq_setup_generic_chip(sd->gc, IRQ_MSK(SDV_NUM_PUB_GPIOS),
179 			IRQ_GC_INIT_MASK_CACHE, IRQ_NOREQUEST,
180 			IRQ_LEVEL | IRQ_NOPROBE);
181 
182 	irq_domain_add(&sd->id);
183 	return 0;
184 out_free_irq:
185 	free_irq(pdev->irq, sd);
186 out_free_desc:
187 	irq_free_descs(sd->irq_base, SDV_NUM_PUB_GPIOS);
188 	return ret;
189 }
190 
191 static int __devinit sdv_gpio_probe(struct pci_dev *pdev,
192 					const struct pci_device_id *pci_id)
193 {
194 	struct sdv_gpio_chip_data *sd;
195 	unsigned long addr;
196 	const void *prop;
197 	int len;
198 	int ret;
199 	u32 mux_val;
200 
201 	sd = kzalloc(sizeof(struct sdv_gpio_chip_data), GFP_KERNEL);
202 	if (!sd)
203 		return -ENOMEM;
204 	ret = pci_enable_device(pdev);
205 	if (ret) {
206 		dev_err(&pdev->dev, "can't enable device.\n");
207 		goto done;
208 	}
209 
210 	ret = pci_request_region(pdev, GPIO_BAR, DRV_NAME);
211 	if (ret) {
212 		dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", GPIO_BAR);
213 		goto disable_pci;
214 	}
215 
216 	addr = pci_resource_start(pdev, GPIO_BAR);
217 	if (!addr)
218 		goto release_reg;
219 	sd->gpio_pub_base = ioremap(addr, pci_resource_len(pdev, GPIO_BAR));
220 
221 	prop = of_get_property(pdev->dev.of_node, "intel,muxctl", &len);
222 	if (prop && len == 4) {
223 		mux_val = of_read_number(prop, 1);
224 		writel(mux_val, sd->gpio_pub_base + GPMUXCTL);
225 	}
226 
227 	ret = bgpio_init(&sd->bgpio, &pdev->dev, 4,
228 			sd->gpio_pub_base + GPINR, sd->gpio_pub_base + GPOUTR,
229 			NULL, sd->gpio_pub_base + GPOER, NULL, false);
230 	if (ret)
231 		goto unmap;
232 	sd->bgpio.gc.ngpio = SDV_NUM_PUB_GPIOS;
233 
234 	ret = gpiochip_add(&sd->bgpio.gc);
235 	if (ret < 0) {
236 		dev_err(&pdev->dev, "gpiochip_add() failed.\n");
237 		goto unmap;
238 	}
239 
240 	ret = sdv_register_irqsupport(sd, pdev);
241 	if (ret)
242 		goto unmap;
243 
244 	pci_set_drvdata(pdev, sd);
245 	dev_info(&pdev->dev, "Sodaville GPIO driver registered.\n");
246 	return 0;
247 
248 unmap:
249 	iounmap(sd->gpio_pub_base);
250 release_reg:
251 	pci_release_region(pdev, GPIO_BAR);
252 disable_pci:
253 	pci_disable_device(pdev);
254 done:
255 	kfree(sd);
256 	return ret;
257 }
258 
259 static void sdv_gpio_remove(struct pci_dev *pdev)
260 {
261 	struct sdv_gpio_chip_data *sd = pci_get_drvdata(pdev);
262 
263 	irq_domain_del(&sd->id);
264 	free_irq(pdev->irq, sd);
265 	irq_free_descs(sd->irq_base, SDV_NUM_PUB_GPIOS);
266 
267 	if (gpiochip_remove(&sd->bgpio.gc))
268 		dev_err(&pdev->dev, "gpiochip_remove() failed.\n");
269 
270 	pci_release_region(pdev, GPIO_BAR);
271 	iounmap(sd->gpio_pub_base);
272 	pci_disable_device(pdev);
273 	kfree(sd);
274 }
275 
276 static struct pci_device_id sdv_gpio_pci_ids[] __devinitdata = {
277 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_SDV_GPIO) },
278 	{ 0, },
279 };
280 
281 static struct pci_driver sdv_gpio_driver = {
282 	.name = DRV_NAME,
283 	.id_table = sdv_gpio_pci_ids,
284 	.probe = sdv_gpio_probe,
285 	.remove = sdv_gpio_remove,
286 };
287 
288 static int __init sdv_gpio_init(void)
289 {
290 	return pci_register_driver(&sdv_gpio_driver);
291 }
292 module_init(sdv_gpio_init);
293 
294 static void __exit sdv_gpio_exit(void)
295 {
296 	pci_unregister_driver(&sdv_gpio_driver);
297 }
298 module_exit(sdv_gpio_exit);
299 
300 MODULE_AUTHOR("Hans J. Koch <hjk@linutronix.de>");
301 MODULE_DESCRIPTION("GPIO interface for Intel Sodaville SoCs");
302 MODULE_LICENSE("GPL v2");
303