xref: /linux/drivers/gpio/gpio-sodaville.c (revision d5efccd5b6843c504042735c1e20d9252daefd98)
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 reg;
55 
56 	if (d->hwirq < 8)
57 		type_reg = sd->gpio_pub_base + GPIT1R0;
58 	else
59 		type_reg = sd->gpio_pub_base + GPIT1R1;
60 
61 	reg = readl(type_reg);
62 
63 	switch (type) {
64 	case IRQ_TYPE_LEVEL_HIGH:
65 		reg &= ~BIT(4 * (d->hwirq % 8));
66 		break;
67 
68 	case IRQ_TYPE_LEVEL_LOW:
69 		reg |= BIT(4 * (d->hwirq % 8));
70 		break;
71 
72 	default:
73 		return -EINVAL;
74 	}
75 
76 	writel(reg, type_reg);
77 	return 0;
78 }
79 
80 static irqreturn_t sdv_gpio_pub_irq_handler(int irq, void *data)
81 {
82 	struct sdv_gpio_chip_data *sd = data;
83 	u32 irq_stat = readl(sd->gpio_pub_base + GPSTR);
84 
85 	irq_stat &= readl(sd->gpio_pub_base + GPIO_INT);
86 	if (!irq_stat)
87 		return IRQ_NONE;
88 
89 	while (irq_stat) {
90 		u32 irq_bit = __fls(irq_stat);
91 
92 		irq_stat &= ~BIT(irq_bit);
93 		generic_handle_irq(irq_find_mapping(sd->id, irq_bit));
94 	}
95 
96 	return IRQ_HANDLED;
97 }
98 
99 static int sdv_xlate(struct irq_domain *h, struct device_node *node,
100 		const u32 *intspec, u32 intsize, irq_hw_number_t *out_hwirq,
101 		u32 *out_type)
102 {
103 	u32 line, type;
104 
105 	if (node != h->of_node)
106 		return -EINVAL;
107 
108 	if (intsize < 2)
109 		return -EINVAL;
110 
111 	line = *intspec;
112 	*out_hwirq = line;
113 
114 	intspec++;
115 	type = *intspec;
116 
117 	switch (type) {
118 	case IRQ_TYPE_LEVEL_LOW:
119 	case IRQ_TYPE_LEVEL_HIGH:
120 		*out_type = type;
121 		break;
122 	default:
123 		return -EINVAL;
124 	}
125 	return 0;
126 }
127 
128 static struct irq_domain_ops irq_domain_sdv_ops = {
129 	.xlate = sdv_xlate,
130 };
131 
132 static __devinit int sdv_register_irqsupport(struct sdv_gpio_chip_data *sd,
133 		struct pci_dev *pdev)
134 {
135 	struct irq_chip_type *ct;
136 	int ret;
137 
138 	sd->irq_base = irq_alloc_descs(-1, 0, SDV_NUM_PUB_GPIOS, -1);
139 	if (sd->irq_base < 0)
140 		return sd->irq_base;
141 
142 	/* mask + ACK all interrupt sources */
143 	writel(0, sd->gpio_pub_base + GPIO_INT);
144 	writel((1 << 11) - 1, sd->gpio_pub_base + GPSTR);
145 
146 	ret = request_irq(pdev->irq, sdv_gpio_pub_irq_handler, IRQF_SHARED,
147 			"sdv_gpio", sd);
148 	if (ret)
149 		goto out_free_desc;
150 
151 	/*
152 	 * This gpio irq controller latches level irqs. Testing shows that if
153 	 * we unmask & ACK the IRQ before the source of the interrupt is gone
154 	 * then the interrupt is active again.
155 	 */
156 	sd->gc = irq_alloc_generic_chip("sdv-gpio", 1, sd->irq_base,
157 			sd->gpio_pub_base, handle_fasteoi_irq);
158 	if (!sd->gc) {
159 		ret = -ENOMEM;
160 		goto out_free_irq;
161 	}
162 
163 	sd->gc->private = sd;
164 	ct = sd->gc->chip_types;
165 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
166 	ct->regs.eoi = GPSTR;
167 	ct->regs.mask = GPIO_INT;
168 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
169 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
170 	ct->chip.irq_eoi = irq_gc_eoi;
171 	ct->chip.irq_set_type = sdv_gpio_pub_set_type;
172 
173 	irq_setup_generic_chip(sd->gc, IRQ_MSK(SDV_NUM_PUB_GPIOS),
174 			IRQ_GC_INIT_MASK_CACHE, IRQ_NOREQUEST,
175 			IRQ_LEVEL | IRQ_NOPROBE);
176 
177 	sd->id = irq_domain_add_legacy(pdev->dev.of_node, SDV_NUM_PUB_GPIOS,
178 				sd->irq_base, 0, &irq_domain_sdv_ops, sd);
179 	if (!sd->id)
180 		goto out_free_irq;
181 	return 0;
182 out_free_irq:
183 	free_irq(pdev->irq, sd);
184 out_free_desc:
185 	irq_free_descs(sd->irq_base, SDV_NUM_PUB_GPIOS);
186 	return ret;
187 }
188 
189 static int __devinit sdv_gpio_probe(struct pci_dev *pdev,
190 					const struct pci_device_id *pci_id)
191 {
192 	struct sdv_gpio_chip_data *sd;
193 	unsigned long addr;
194 	const void *prop;
195 	int len;
196 	int ret;
197 	u32 mux_val;
198 
199 	sd = kzalloc(sizeof(struct sdv_gpio_chip_data), GFP_KERNEL);
200 	if (!sd)
201 		return -ENOMEM;
202 	ret = pci_enable_device(pdev);
203 	if (ret) {
204 		dev_err(&pdev->dev, "can't enable device.\n");
205 		goto done;
206 	}
207 
208 	ret = pci_request_region(pdev, GPIO_BAR, DRV_NAME);
209 	if (ret) {
210 		dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", GPIO_BAR);
211 		goto disable_pci;
212 	}
213 
214 	addr = pci_resource_start(pdev, GPIO_BAR);
215 	if (!addr)
216 		goto release_reg;
217 	sd->gpio_pub_base = ioremap(addr, pci_resource_len(pdev, GPIO_BAR));
218 
219 	prop = of_get_property(pdev->dev.of_node, "intel,muxctl", &len);
220 	if (prop && len == 4) {
221 		mux_val = of_read_number(prop, 1);
222 		writel(mux_val, sd->gpio_pub_base + GPMUXCTL);
223 	}
224 
225 	ret = bgpio_init(&sd->bgpio, &pdev->dev, 4,
226 			sd->gpio_pub_base + GPINR, sd->gpio_pub_base + GPOUTR,
227 			NULL, sd->gpio_pub_base + GPOER, NULL, false);
228 	if (ret)
229 		goto unmap;
230 	sd->bgpio.gc.ngpio = SDV_NUM_PUB_GPIOS;
231 
232 	ret = gpiochip_add(&sd->bgpio.gc);
233 	if (ret < 0) {
234 		dev_err(&pdev->dev, "gpiochip_add() failed.\n");
235 		goto unmap;
236 	}
237 
238 	ret = sdv_register_irqsupport(sd, pdev);
239 	if (ret)
240 		goto unmap;
241 
242 	pci_set_drvdata(pdev, sd);
243 	dev_info(&pdev->dev, "Sodaville GPIO driver registered.\n");
244 	return 0;
245 
246 unmap:
247 	iounmap(sd->gpio_pub_base);
248 release_reg:
249 	pci_release_region(pdev, GPIO_BAR);
250 disable_pci:
251 	pci_disable_device(pdev);
252 done:
253 	kfree(sd);
254 	return ret;
255 }
256 
257 static void sdv_gpio_remove(struct pci_dev *pdev)
258 {
259 	struct sdv_gpio_chip_data *sd = pci_get_drvdata(pdev);
260 
261 	free_irq(pdev->irq, sd);
262 	irq_free_descs(sd->irq_base, SDV_NUM_PUB_GPIOS);
263 
264 	if (gpiochip_remove(&sd->bgpio.gc))
265 		dev_err(&pdev->dev, "gpiochip_remove() failed.\n");
266 
267 	pci_release_region(pdev, GPIO_BAR);
268 	iounmap(sd->gpio_pub_base);
269 	pci_disable_device(pdev);
270 	kfree(sd);
271 }
272 
273 static struct pci_device_id sdv_gpio_pci_ids[] __devinitdata = {
274 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_SDV_GPIO) },
275 	{ 0, },
276 };
277 
278 static struct pci_driver sdv_gpio_driver = {
279 	.name = DRV_NAME,
280 	.id_table = sdv_gpio_pci_ids,
281 	.probe = sdv_gpio_probe,
282 	.remove = sdv_gpio_remove,
283 };
284 
285 static int __init sdv_gpio_init(void)
286 {
287 	return pci_register_driver(&sdv_gpio_driver);
288 }
289 module_init(sdv_gpio_init);
290 
291 static void __exit sdv_gpio_exit(void)
292 {
293 	pci_unregister_driver(&sdv_gpio_driver);
294 }
295 module_exit(sdv_gpio_exit);
296 
297 MODULE_AUTHOR("Hans J. Koch <hjk@linutronix.de>");
298 MODULE_DESCRIPTION("GPIO interface for Intel Sodaville SoCs");
299 MODULE_LICENSE("GPL v2");
300