xref: /linux/drivers/gpio/gpio-sodaville.c (revision 55a42f78ffd386e01a5404419f8c5ded7db70a21)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  GPIO interface for Intel Sodaville SoCs.
4  *
5  *  Copyright (c) 2010, 2011 Intel Corporation
6  *
7  *  Author: Hans J. Koch <hjk@linutronix.de>
8  */
9 
10 #include <linux/errno.h>
11 #include <linux/gpio/driver.h>
12 #include <linux/gpio/generic.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 #include <linux/kernel.h>
18 #include <linux/of_irq.h>
19 #include <linux/pci.h>
20 #include <linux/platform_device.h>
21 
22 #define DRV_NAME		"sdv_gpio"
23 #define SDV_NUM_PUB_GPIOS	12
24 #define PCI_DEVICE_ID_SDV_GPIO	0x2e67
25 #define GPIO_BAR		0
26 
27 #define GPOUTR		0x00
28 #define GPOER		0x04
29 #define GPINR		0x08
30 
31 #define GPSTR		0x0c
32 #define GPIT1R0		0x10
33 #define GPIO_INT	0x14
34 #define GPIT1R1		0x18
35 
36 #define GPMUXCTL	0x1c
37 
38 struct sdv_gpio_chip_data {
39 	int irq_base;
40 	void __iomem *gpio_pub_base;
41 	struct irq_domain *id;
42 	struct irq_chip_generic *gc;
43 	struct gpio_generic_chip gen_gc;
44 };
45 
46 static int sdv_gpio_pub_set_type(struct irq_data *d, unsigned int type)
47 {
48 	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
49 	struct sdv_gpio_chip_data *sd = gc->private;
50 	void __iomem *type_reg;
51 	u32 reg;
52 
53 	if (d->hwirq < 8)
54 		type_reg = sd->gpio_pub_base + GPIT1R0;
55 	else
56 		type_reg = sd->gpio_pub_base + GPIT1R1;
57 
58 	reg = readl(type_reg);
59 
60 	switch (type) {
61 	case IRQ_TYPE_LEVEL_HIGH:
62 		reg &= ~BIT(4 * (d->hwirq % 8));
63 		break;
64 
65 	case IRQ_TYPE_LEVEL_LOW:
66 		reg |= BIT(4 * (d->hwirq % 8));
67 		break;
68 
69 	default:
70 		return -EINVAL;
71 	}
72 
73 	writel(reg, type_reg);
74 	return 0;
75 }
76 
77 static irqreturn_t sdv_gpio_pub_irq_handler(int irq, void *data)
78 {
79 	struct sdv_gpio_chip_data *sd = data;
80 	unsigned long irq_stat = readl(sd->gpio_pub_base + GPSTR);
81 	int irq_bit;
82 
83 	irq_stat &= readl(sd->gpio_pub_base + GPIO_INT);
84 	if (!irq_stat)
85 		return IRQ_NONE;
86 
87 	for_each_set_bit(irq_bit, &irq_stat, 32)
88 		generic_handle_domain_irq(sd->id, irq_bit);
89 
90 	return IRQ_HANDLED;
91 }
92 
93 static int sdv_xlate(struct irq_domain *h, struct device_node *node,
94 		const u32 *intspec, u32 intsize, irq_hw_number_t *out_hwirq,
95 		u32 *out_type)
96 {
97 	u32 line, type;
98 
99 	if (node != irq_domain_get_of_node(h))
100 		return -EINVAL;
101 
102 	if (intsize < 2)
103 		return -EINVAL;
104 
105 	line = *intspec;
106 	*out_hwirq = line;
107 
108 	intspec++;
109 	type = *intspec;
110 
111 	switch (type) {
112 	case IRQ_TYPE_LEVEL_LOW:
113 	case IRQ_TYPE_LEVEL_HIGH:
114 		*out_type = type;
115 		break;
116 	default:
117 		return -EINVAL;
118 	}
119 	return 0;
120 }
121 
122 static const struct irq_domain_ops irq_domain_sdv_ops = {
123 	.xlate = sdv_xlate,
124 };
125 
126 static int sdv_register_irqsupport(struct sdv_gpio_chip_data *sd,
127 		struct pci_dev *pdev)
128 {
129 	struct irq_chip_type *ct;
130 	int ret;
131 
132 	sd->irq_base = devm_irq_alloc_descs(&pdev->dev, -1, 0,
133 					    SDV_NUM_PUB_GPIOS, -1);
134 	if (sd->irq_base < 0)
135 		return sd->irq_base;
136 
137 	/* mask + ACK all interrupt sources */
138 	writel(0, sd->gpio_pub_base + GPIO_INT);
139 	writel((1 << 11) - 1, sd->gpio_pub_base + GPSTR);
140 
141 	ret = devm_request_irq(&pdev->dev, pdev->irq,
142 			       sdv_gpio_pub_irq_handler, IRQF_SHARED,
143 			       "sdv_gpio", sd);
144 	if (ret)
145 		return ret;
146 
147 	/*
148 	 * This gpio irq controller latches level irqs. Testing shows that if
149 	 * we unmask & ACK the IRQ before the source of the interrupt is gone
150 	 * then the interrupt is active again.
151 	 */
152 	sd->gc = devm_irq_alloc_generic_chip(&pdev->dev, "sdv-gpio", 1,
153 					     sd->irq_base,
154 					     sd->gpio_pub_base,
155 					     handle_fasteoi_irq);
156 	if (!sd->gc)
157 		return -ENOMEM;
158 
159 	sd->gc->private = sd;
160 	ct = sd->gc->chip_types;
161 	ct->type = IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW;
162 	ct->regs.eoi = GPSTR;
163 	ct->regs.mask = GPIO_INT;
164 	ct->chip.irq_mask = irq_gc_mask_clr_bit;
165 	ct->chip.irq_unmask = irq_gc_mask_set_bit;
166 	ct->chip.irq_eoi = irq_gc_eoi;
167 	ct->chip.irq_set_type = sdv_gpio_pub_set_type;
168 
169 	irq_setup_generic_chip(sd->gc, IRQ_MSK(SDV_NUM_PUB_GPIOS),
170 			IRQ_GC_INIT_MASK_CACHE, IRQ_NOREQUEST,
171 			IRQ_LEVEL | IRQ_NOPROBE);
172 
173 	sd->id = irq_domain_create_legacy(dev_fwnode(&pdev->dev), SDV_NUM_PUB_GPIOS, sd->irq_base,
174 					  0, &irq_domain_sdv_ops, sd);
175 	if (!sd->id)
176 		return -ENODEV;
177 
178 	return 0;
179 }
180 
181 static int sdv_gpio_probe(struct pci_dev *pdev,
182 					const struct pci_device_id *pci_id)
183 {
184 	struct gpio_generic_chip_config config;
185 	struct sdv_gpio_chip_data *sd;
186 	int ret;
187 	u32 mux_val;
188 
189 	sd = devm_kzalloc(&pdev->dev, sizeof(*sd), GFP_KERNEL);
190 	if (!sd)
191 		return -ENOMEM;
192 
193 	ret = pcim_enable_device(pdev);
194 	if (ret) {
195 		dev_err(&pdev->dev, "can't enable device.\n");
196 		return ret;
197 	}
198 
199 	ret = pcim_iomap_regions(pdev, 1 << GPIO_BAR, DRV_NAME);
200 	if (ret) {
201 		dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", GPIO_BAR);
202 		return ret;
203 	}
204 
205 	sd->gpio_pub_base = pcim_iomap_table(pdev)[GPIO_BAR];
206 
207 	ret = of_property_read_u32(pdev->dev.of_node, "intel,muxctl", &mux_val);
208 	if (!ret)
209 		writel(mux_val, sd->gpio_pub_base + GPMUXCTL);
210 
211 	config = (struct gpio_generic_chip_config) {
212 		.dev = &pdev->dev,
213 		.sz = 4,
214 		.dat = sd->gpio_pub_base + GPINR,
215 		.set = sd->gpio_pub_base + GPOUTR,
216 		.dirout = sd->gpio_pub_base + GPOER,
217 	};
218 
219 	ret = gpio_generic_chip_init(&sd->gen_gc, &config);
220 	if (ret)
221 		return ret;
222 
223 	sd->gen_gc.gc.ngpio = SDV_NUM_PUB_GPIOS;
224 
225 	ret = devm_gpiochip_add_data(&pdev->dev, &sd->gen_gc.gc, sd);
226 	if (ret < 0) {
227 		dev_err(&pdev->dev, "gpiochip_add() failed.\n");
228 		return ret;
229 	}
230 
231 	ret = sdv_register_irqsupport(sd, pdev);
232 	if (ret)
233 		return ret;
234 
235 	pci_set_drvdata(pdev, sd);
236 	dev_info(&pdev->dev, "Sodaville GPIO driver registered.\n");
237 	return 0;
238 }
239 
240 static const struct pci_device_id sdv_gpio_pci_ids[] = {
241 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_SDV_GPIO) },
242 	{ 0, },
243 };
244 
245 static struct pci_driver sdv_gpio_driver = {
246 	.driver = {
247 		.suppress_bind_attrs = true,
248 	},
249 	.name = DRV_NAME,
250 	.id_table = sdv_gpio_pci_ids,
251 	.probe = sdv_gpio_probe,
252 };
253 builtin_pci_driver(sdv_gpio_driver);
254