1 /*
2 * GPIO interface for Intel Sodaville SoCs.
3 *
4 * Copyright (c) 2010, 2011 Intel Corporation
5 *
6 * Author: Hans J. Koch <hjk@linutronix.de>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License 2 as published
10 * by the Free Software Foundation.
11 *
12 */
13
14 #include <linux/errno.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17 #include <linux/irq.h>
18 #include <linux/interrupt.h>
19 #include <linux/kernel.h>
20 #include <linux/pci.h>
21 #include <linux/platform_device.h>
22 #include <linux/of_irq.h>
23 #include <linux/gpio/driver.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 gpio_chip chip;
47 };
48
sdv_gpio_pub_set_type(struct irq_data * d,unsigned int type)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
sdv_gpio_pub_irq_handler(int irq,void * data)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
sdv_xlate(struct irq_domain * h,struct device_node * node,const u32 * intspec,u32 intsize,irq_hw_number_t * out_hwirq,u32 * out_type)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 != irq_domain_get_of_node(h))
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 const struct irq_domain_ops irq_domain_sdv_ops = {
129 .xlate = sdv_xlate,
130 };
131
sdv_register_irqsupport(struct sdv_gpio_chip_data * sd,struct pci_dev * pdev)132 static 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 = devm_irq_alloc_descs(&pdev->dev, -1, 0,
139 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 = devm_request_irq(&pdev->dev, pdev->irq,
148 sdv_gpio_pub_irq_handler, IRQF_SHARED,
149 "sdv_gpio", sd);
150 if (ret)
151 return ret;
152
153 /*
154 * This gpio irq controller latches level irqs. Testing shows that if
155 * we unmask & ACK the IRQ before the source of the interrupt is gone
156 * then the interrupt is active again.
157 */
158 sd->gc = irq_alloc_generic_chip("sdv-gpio", 1, sd->irq_base,
159 sd->gpio_pub_base, handle_fasteoi_irq);
160 if (!sd->gc)
161 return -ENOMEM;
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 return -ENODEV;
181
182 return 0;
183 }
184
sdv_gpio_probe(struct pci_dev * pdev,const struct pci_device_id * pci_id)185 static int sdv_gpio_probe(struct pci_dev *pdev,
186 const struct pci_device_id *pci_id)
187 {
188 struct sdv_gpio_chip_data *sd;
189 unsigned long addr;
190 const void *prop;
191 int len;
192 int ret;
193 u32 mux_val;
194
195 sd = kzalloc(sizeof(struct sdv_gpio_chip_data), GFP_KERNEL);
196 if (!sd)
197 return -ENOMEM;
198 ret = pci_enable_device(pdev);
199 if (ret) {
200 dev_err(&pdev->dev, "can't enable device.\n");
201 goto done;
202 }
203
204 ret = pci_request_region(pdev, GPIO_BAR, DRV_NAME);
205 if (ret) {
206 dev_err(&pdev->dev, "can't alloc PCI BAR #%d\n", GPIO_BAR);
207 goto disable_pci;
208 }
209
210 addr = pci_resource_start(pdev, GPIO_BAR);
211 if (!addr) {
212 ret = -ENODEV;
213 goto release_reg;
214 }
215 sd->gpio_pub_base = ioremap(addr, pci_resource_len(pdev, GPIO_BAR));
216
217 prop = of_get_property(pdev->dev.of_node, "intel,muxctl", &len);
218 if (prop && len == 4) {
219 mux_val = of_read_number(prop, 1);
220 writel(mux_val, sd->gpio_pub_base + GPMUXCTL);
221 }
222
223 ret = bgpio_init(&sd->chip, &pdev->dev, 4,
224 sd->gpio_pub_base + GPINR, sd->gpio_pub_base + GPOUTR,
225 NULL, sd->gpio_pub_base + GPOER, NULL, 0);
226 if (ret)
227 goto unmap;
228 sd->chip.ngpio = SDV_NUM_PUB_GPIOS;
229
230 ret = gpiochip_add_data(&sd->chip, sd);
231 if (ret < 0) {
232 dev_err(&pdev->dev, "gpiochip_add() failed.\n");
233 goto unmap;
234 }
235
236 ret = sdv_register_irqsupport(sd, pdev);
237 if (ret)
238 goto unmap;
239
240 pci_set_drvdata(pdev, sd);
241 dev_info(&pdev->dev, "Sodaville GPIO driver registered.\n");
242 return 0;
243
244 unmap:
245 iounmap(sd->gpio_pub_base);
246 release_reg:
247 pci_release_region(pdev, GPIO_BAR);
248 disable_pci:
249 pci_disable_device(pdev);
250 done:
251 kfree(sd);
252 return ret;
253 }
254
255 static const struct pci_device_id sdv_gpio_pci_ids[] = {
256 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_SDV_GPIO) },
257 { 0, },
258 };
259
260 static struct pci_driver sdv_gpio_driver = {
261 .driver = {
262 .suppress_bind_attrs = true,
263 },
264 .name = DRV_NAME,
265 .id_table = sdv_gpio_pci_ids,
266 .probe = sdv_gpio_probe,
267 };
268 builtin_pci_driver(sdv_gpio_driver);
269