1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Intel MID GPIO driver
4 *
5 * Copyright (c) 2008-2014,2016 Intel Corporation.
6 */
7
8/* Supports:
9 * Moorestown platform Langwell chip.
10 * Medfield platform Penwell chip.
11 * Clovertrail platform Cloverview chip.
12 */
13
14#include <linux/delay.h>
15#include <linux/gpio/driver.h>
16#include <linux/init.h>
17#include <linux/interrupt.h>
18#include <linux/io.h>
19#include <linux/kernel.h>
20#include <linux/pci.h>
21#include <linux/platform_device.h>
22#include <linux/pm_runtime.h>
23#include <linux/slab.h>
24#include <linux/stddef.h>
25
26#define INTEL_MID_IRQ_TYPE_EDGE (1 << 0)
27#define INTEL_MID_IRQ_TYPE_LEVEL (1 << 1)
28
29/*
30 * Langwell chip has 64 pins and thus there are 2 32bit registers to control
31 * each feature, while Penwell chip has 96 pins for each block, and need 3 32bit
32 * registers to control them, so we only define the order here instead of a
33 * structure, to get a bit offset for a pin (use GPDR as an example):
34 *
35 * nreg = ngpio / 32;
36 * reg = offset / 32;
37 * bit = offset % 32;
38 * reg_addr = reg_base + GPDR * nreg * 4 + reg * 4;
39 *
40 * so the bit of reg_addr is to control pin offset's GPDR feature
41*/
42
43enum GPIO_REG {
44 GPLR = 0, /* pin level read-only */
45 GPDR, /* pin direction */
46 GPSR, /* pin set */
47 GPCR, /* pin clear */
48 GRER, /* rising edge detect */
49 GFER, /* falling edge detect */
50 GEDR, /* edge detect result */
51 GAFR, /* alt function */
52};
53
54/* intel_mid gpio driver data */
55struct intel_mid_gpio_ddata {
56 u16 ngpio; /* number of gpio pins */
57 u32 chip_irq_type; /* chip interrupt type */
58};
59
60struct intel_mid_gpio {
61 struct gpio_chip chip;
62 void __iomem *reg_base;
63 spinlock_t lock;
64 struct pci_dev *pdev;
65};
66
67static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned offset,
68 enum GPIO_REG reg_type)
69{
70 struct intel_mid_gpio *priv = gpiochip_get_data(chip);
71 unsigned nreg = chip->ngpio / 32;
72 u8 reg = offset / 32;
73
74 return priv->reg_base + reg_type * nreg * 4 + reg * 4;
75}
76
77static void __iomem *gpio_reg_2bit(struct gpio_chip *chip, unsigned offset,
78 enum GPIO_REG reg_type)
79{
80 struct intel_mid_gpio *priv = gpiochip_get_data(chip);
81 unsigned nreg = chip->ngpio / 32;
82 u8 reg = offset / 16;
83
84 return priv->reg_base + reg_type * nreg * 4 + reg * 4;
85}
86
87static int intel_gpio_request(struct gpio_chip *chip, unsigned offset)
88{
89 void __iomem *gafr = gpio_reg_2bit(chip, offset, GAFR);
90 u32 value = readl(gafr);
91 int shift = (offset % 16) << 1, af = (value >> shift) & 3;
92
93 if (af) {
94 value &= ~(3 << shift);
95 writel(value, gafr);
96 }
97 return 0;
98}
99
100static int intel_gpio_get(struct gpio_chip *chip, unsigned offset)
101{
102 void __iomem *gplr = gpio_reg(chip, offset, GPLR);
103
104 return !!(readl(gplr) & BIT(offset % 32));
105}
106
107static void intel_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
108{
109 void __iomem *gpsr, *gpcr;
110
111 if (value) {
112 gpsr = gpio_reg(chip, offset, GPSR);
113 writel(BIT(offset % 32), gpsr);
114 } else {
115 gpcr = gpio_reg(chip, offset, GPCR);
116 writel(BIT(offset % 32), gpcr);
117 }
118}
119
120static int intel_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
121{
122 struct intel_mid_gpio *priv = gpiochip_get_data(chip);
123 void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
124 u32 value;
125 unsigned long flags;
126
127 if (priv->pdev)
128 pm_runtime_get(&priv->pdev->dev);
129
130 spin_lock_irqsave(&priv->lock, flags);
131 value = readl(gpdr);
132 value &= ~BIT(offset % 32);
133 writel(value, gpdr);
134 spin_unlock_irqrestore(&priv->lock, flags);
135
136 if (priv->pdev)
137 pm_runtime_put(&priv->pdev->dev);
138
139 return 0;
140}
141
142static int intel_gpio_direction_output(struct gpio_chip *chip,
143 unsigned offset, int value)
144{
145 struct intel_mid_gpio *priv = gpiochip_get_data(chip);
146 void __iomem *gpdr = gpio_reg(chip, offset, GPDR);
147 unsigned long flags;
148
149 intel_gpio_set(chip, offset, value);
150
151 if (priv->pdev)
152 pm_runtime_get(&priv->pdev->dev);
153
154 spin_lock_irqsave(&priv->lock, flags);
155 value = readl(gpdr);
156 value |= BIT(offset % 32);
157 writel(value, gpdr);
158 spin_unlock_irqrestore(&priv->lock, flags);
159
160 if (priv->pdev)
161 pm_runtime_put(&priv->pdev->dev);
162
163 return 0;
164}
165
166static int intel_mid_irq_type(struct irq_data *d, unsigned type)
167{
168 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
169 struct intel_mid_gpio *priv = gpiochip_get_data(gc);
170 u32 gpio = irqd_to_hwirq(d);
171 unsigned long flags;
172 u32 value;
173 void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
174 void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
175
176 if (gpio >= priv->chip.ngpio)
177 return -EINVAL;
178
179 if (priv->pdev)
180 pm_runtime_get(&priv->pdev->dev);
181
182 spin_lock_irqsave(&priv->lock, flags);
183 if (type & IRQ_TYPE_EDGE_RISING)
184 value = readl(grer) | BIT(gpio % 32);
185 else
186 value = readl(grer) & (~BIT(gpio % 32));
187 writel(value, grer);
188
189 if (type & IRQ_TYPE_EDGE_FALLING)
190 value = readl(gfer) | BIT(gpio % 32);
191 else
192 value = readl(gfer) & (~BIT(gpio % 32));
193 writel(value, gfer);
194 spin_unlock_irqrestore(&priv->lock, flags);
195
196 if (priv->pdev)
197 pm_runtime_put(&priv->pdev->dev);
198
199 return 0;
200}
201
202static void intel_mid_irq_unmask(struct irq_data *d)
203{
204}
205
206static void intel_mid_irq_mask(struct irq_data *d)
207{
208}
209
210static struct irq_chip intel_mid_irqchip = {
211 .name = "INTEL_MID-GPIO",
212 .irq_mask = intel_mid_irq_mask,
213 .irq_unmask = intel_mid_irq_unmask,
214 .irq_set_type = intel_mid_irq_type,
215};
216
217static const struct intel_mid_gpio_ddata gpio_lincroft = {
218 .ngpio = 64,
219};
220
221static const struct intel_mid_gpio_ddata gpio_penwell_aon = {
222 .ngpio = 96,
223 .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
224};
225
226static const struct intel_mid_gpio_ddata gpio_penwell_core = {
227 .ngpio = 96,
228 .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
229};
230
231static const struct intel_mid_gpio_ddata gpio_cloverview_aon = {
232 .ngpio = 96,
233 .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE | INTEL_MID_IRQ_TYPE_LEVEL,
234};
235
236static const struct intel_mid_gpio_ddata gpio_cloverview_core = {
237 .ngpio = 96,
238 .chip_irq_type = INTEL_MID_IRQ_TYPE_EDGE,
239};
240
241static const struct pci_device_id intel_gpio_ids[] = {
242 {
243 /* Lincroft */
244 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x080f),
245 .driver_data = (kernel_ulong_t)&gpio_lincroft,
246 },
247 {
248 /* Penwell AON */
249 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081f),
250 .driver_data = (kernel_ulong_t)&gpio_penwell_aon,
251 },
252 {
253 /* Penwell Core */
254 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081a),
255 .driver_data = (kernel_ulong_t)&gpio_penwell_core,
256 },
257 {
258 /* Cloverview Aon */
259 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08eb),
260 .driver_data = (kernel_ulong_t)&gpio_cloverview_aon,
261 },
262 {
263 /* Cloverview Core */
264 PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x08f7),
265 .driver_data = (kernel_ulong_t)&gpio_cloverview_core,
266 },
267 { }
268};
269
270static void intel_mid_irq_handler(struct irq_desc *desc)
271{
272 struct gpio_chip *gc = irq_desc_get_handler_data(desc);
273 struct intel_mid_gpio *priv = gpiochip_get_data(gc);
274 struct irq_data *data = irq_desc_get_irq_data(desc);
275 struct irq_chip *chip = irq_data_get_irq_chip(data);
276 u32 base, gpio, mask;
277 unsigned long pending;
278 void __iomem *gedr;
279
280 /* check GPIO controller to check which pin triggered the interrupt */
281 for (base = 0; base < priv->chip.ngpio; base += 32) {
282 gedr = gpio_reg(&priv->chip, base, GEDR);
283 while ((pending = readl(gedr))) {
284 gpio = __ffs(pending);
285 mask = BIT(gpio);
286 /* Clear before handling so we can't lose an edge */
287 writel(mask, gedr);
288 generic_handle_irq(irq_find_mapping(gc->irq.domain,
289 base + gpio));
290 }
291 }
292
293 chip->irq_eoi(data);
294}
295
296static void intel_mid_irq_init_hw(struct intel_mid_gpio *priv)
297{
298 void __iomem *reg;
299 unsigned base;
300
301 for (base = 0; base < priv->chip.ngpio; base += 32) {
302 /* Clear the rising-edge detect register */
303 reg = gpio_reg(&priv->chip, base, GRER);
304 writel(0, reg);
305 /* Clear the falling-edge detect register */
306 reg = gpio_reg(&priv->chip, base, GFER);
307 writel(0, reg);
308 /* Clear the edge detect status register */
309 reg = gpio_reg(&priv->chip, base, GEDR);
310 writel(~0, reg);
311 }
312}
313
314static int __maybe_unused intel_gpio_runtime_idle(struct device *dev)
315{
316 int err = pm_schedule_suspend(dev, 500);
317 return err ?: -EBUSY;
318}
319
320static const struct dev_pm_ops intel_gpio_pm_ops = {
321 SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
322};
323
324static int intel_gpio_probe(struct pci_dev *pdev,
325 const struct pci_device_id *id)
326{
327 void __iomem *base;
328 struct intel_mid_gpio *priv;
329 u32 gpio_base;
330 u32 irq_base;
331 int retval;
332 struct intel_mid_gpio_ddata *ddata =
333 (struct intel_mid_gpio_ddata *)id->driver_data;
334
335 retval = pcim_enable_device(pdev);
336 if (retval)
337 return retval;
338
339 retval = pcim_iomap_regions(pdev, 1 << 0 | 1 << 1, pci_name(pdev));
340 if (retval) {
341 dev_err(&pdev->dev, "I/O memory mapping error\n");
342 return retval;
343 }
344
345 base = pcim_iomap_table(pdev)[1];
346
347 irq_base = readl(base);
348 gpio_base = readl(sizeof(u32) + base);
349
350 /* release the IO mapping, since we already get the info from bar1 */
351 pcim_iounmap_regions(pdev, 1 << 1);
352
353 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
354 if (!priv)
355 return -ENOMEM;
356
357 priv->reg_base = pcim_iomap_table(pdev)[0];
358 priv->chip.label = dev_name(&pdev->dev);
359 priv->chip.parent = &pdev->dev;
360 priv->chip.request = intel_gpio_request;
361 priv->chip.direction_input = intel_gpio_direction_input;
362 priv->chip.direction_output = intel_gpio_direction_output;
363 priv->chip.get = intel_gpio_get;
364 priv->chip.set = intel_gpio_set;
365 priv->chip.base = gpio_base;
366 priv->chip.ngpio = ddata->ngpio;
367 priv->chip.can_sleep = false;
368 priv->pdev = pdev;
369
370 spin_lock_init(&priv->lock);
371
372 pci_set_drvdata(pdev, priv);
373 retval = devm_gpiochip_add_data(&pdev->dev, &priv->chip, priv);
374 if (retval) {
375 dev_err(&pdev->dev, "gpiochip_add error %d\n", retval);
376 return retval;
377 }
378
379 retval = gpiochip_irqchip_add(&priv->chip,
380 &intel_mid_irqchip,
381 irq_base,
382 handle_simple_irq,
383 IRQ_TYPE_NONE);
384 if (retval) {
385 dev_err(&pdev->dev,
386 "could not connect irqchip to gpiochip\n");
387 return retval;
388 }
389
390 intel_mid_irq_init_hw(priv);
391
392 gpiochip_set_chained_irqchip(&priv->chip,
393 &intel_mid_irqchip,
394 pdev->irq,
395 intel_mid_irq_handler);
396
397 pm_runtime_put_noidle(&pdev->dev);
398 pm_runtime_allow(&pdev->dev);
399
400 return 0;
401}
402
403static struct pci_driver intel_gpio_driver = {
404 .name = "intel_mid_gpio",
405 .id_table = intel_gpio_ids,
406 .probe = intel_gpio_probe,
407 .driver = {
408 .pm = &intel_gpio_pm_ops,
409 },
410};
411
412builtin_pci_driver(intel_gpio_driver);
413