1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Freescale vf610 GPIO support through PORT and GPIO
4 *
5 * Copyright (c) 2014 Toradex AG.
6 *
7 * Author: Stefan Agner <stefan@agner.ch>.
8 */
9#include <linux/bitops.h>
10#include <linux/clk.h>
11#include <linux/err.h>
12#include <linux/gpio/driver.h>
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/io.h>
16#include <linux/ioport.h>
17#include <linux/irq.h>
18#include <linux/platform_device.h>
19#include <linux/of.h>
20#include <linux/of_device.h>
21#include <linux/of_irq.h>
22
23#define VF610_GPIO_PER_PORT		32
24
25struct fsl_gpio_soc_data {
26	/* SoCs has a Port Data Direction Register (PDDR) */
27	bool have_paddr;
28};
29
30struct vf610_gpio_port {
31	struct gpio_chip gc;
32	struct irq_chip ic;
33	void __iomem *base;
34	void __iomem *gpio_base;
35	const struct fsl_gpio_soc_data *sdata;
36	u8 irqc[VF610_GPIO_PER_PORT];
37	struct clk *clk_port;
38	struct clk *clk_gpio;
39	int irq;
40};
41
42#define GPIO_PDOR		0x00
43#define GPIO_PSOR		0x04
44#define GPIO_PCOR		0x08
45#define GPIO_PTOR		0x0c
46#define GPIO_PDIR		0x10
47#define GPIO_PDDR		0x14
48
49#define PORT_PCR(n)		((n) * 0x4)
50#define PORT_PCR_IRQC_OFFSET	16
51
52#define PORT_ISFR		0xa0
53#define PORT_DFER		0xc0
54#define PORT_DFCR		0xc4
55#define PORT_DFWR		0xc8
56
57#define PORT_INT_OFF		0x0
58#define PORT_INT_LOGIC_ZERO	0x8
59#define PORT_INT_RISING_EDGE	0x9
60#define PORT_INT_FALLING_EDGE	0xa
61#define PORT_INT_EITHER_EDGE	0xb
62#define PORT_INT_LOGIC_ONE	0xc
63
64static const struct fsl_gpio_soc_data imx_data = {
65	.have_paddr = true,
66};
67
68static const struct of_device_id vf610_gpio_dt_ids[] = {
69	{ .compatible = "fsl,vf610-gpio",	.data = NULL, },
70	{ .compatible = "fsl,imx7ulp-gpio",	.data = &imx_data, },
71	{ /* sentinel */ }
72};
73
74static inline void vf610_gpio_writel(u32 val, void __iomem *reg)
75{
76	writel_relaxed(val, reg);
77}
78
79static inline u32 vf610_gpio_readl(void __iomem *reg)
80{
81	return readl_relaxed(reg);
82}
83
84static int vf610_gpio_get(struct gpio_chip *gc, unsigned int gpio)
85{
86	struct vf610_gpio_port *port = gpiochip_get_data(gc);
87	unsigned long mask = BIT(gpio);
88	unsigned long offset = GPIO_PDIR;
89
90	if (port->sdata && port->sdata->have_paddr) {
91		mask &= vf610_gpio_readl(port->gpio_base + GPIO_PDDR);
92		if (mask)
93			offset = GPIO_PDOR;
94	}
95
96	return !!(vf610_gpio_readl(port->gpio_base + offset) & BIT(gpio));
97}
98
99static void vf610_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
100{
101	struct vf610_gpio_port *port = gpiochip_get_data(gc);
102	unsigned long mask = BIT(gpio);
103	unsigned long offset = val ? GPIO_PSOR : GPIO_PCOR;
104
105	vf610_gpio_writel(mask, port->gpio_base + offset);
106}
107
108static int vf610_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
109{
110	struct vf610_gpio_port *port = gpiochip_get_data(chip);
111	unsigned long mask = BIT(gpio);
112	u32 val;
113
114	if (port->sdata && port->sdata->have_paddr) {
115		val = vf610_gpio_readl(port->gpio_base + GPIO_PDDR);
116		val &= ~mask;
117		vf610_gpio_writel(val, port->gpio_base + GPIO_PDDR);
118	}
119
120	return pinctrl_gpio_direction_input(chip->base + gpio);
121}
122
123static int vf610_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
124				       int value)
125{
126	struct vf610_gpio_port *port = gpiochip_get_data(chip);
127	unsigned long mask = BIT(gpio);
128	u32 val;
129
130	vf610_gpio_set(chip, gpio, value);
131
132	if (port->sdata && port->sdata->have_paddr) {
133		val = vf610_gpio_readl(port->gpio_base + GPIO_PDDR);
134		val |= mask;
135		vf610_gpio_writel(val, port->gpio_base + GPIO_PDDR);
136	}
137
138	return pinctrl_gpio_direction_output(chip->base + gpio);
139}
140
141static void vf610_gpio_irq_handler(struct irq_desc *desc)
142{
143	struct vf610_gpio_port *port =
144		gpiochip_get_data(irq_desc_get_handler_data(desc));
145	struct irq_chip *chip = irq_desc_get_chip(desc);
146	int pin;
147	unsigned long irq_isfr;
148
149	chained_irq_enter(chip, desc);
150
151	irq_isfr = vf610_gpio_readl(port->base + PORT_ISFR);
152
153	for_each_set_bit(pin, &irq_isfr, VF610_GPIO_PER_PORT) {
154		vf610_gpio_writel(BIT(pin), port->base + PORT_ISFR);
155
156		generic_handle_irq(irq_find_mapping(port->gc.irq.domain, pin));
157	}
158
159	chained_irq_exit(chip, desc);
160}
161
162static void vf610_gpio_irq_ack(struct irq_data *d)
163{
164	struct vf610_gpio_port *port =
165		gpiochip_get_data(irq_data_get_irq_chip_data(d));
166	int gpio = d->hwirq;
167
168	vf610_gpio_writel(BIT(gpio), port->base + PORT_ISFR);
169}
170
171static int vf610_gpio_irq_set_type(struct irq_data *d, u32 type)
172{
173	struct vf610_gpio_port *port =
174		gpiochip_get_data(irq_data_get_irq_chip_data(d));
175	u8 irqc;
176
177	switch (type) {
178	case IRQ_TYPE_EDGE_RISING:
179		irqc = PORT_INT_RISING_EDGE;
180		break;
181	case IRQ_TYPE_EDGE_FALLING:
182		irqc = PORT_INT_FALLING_EDGE;
183		break;
184	case IRQ_TYPE_EDGE_BOTH:
185		irqc = PORT_INT_EITHER_EDGE;
186		break;
187	case IRQ_TYPE_LEVEL_LOW:
188		irqc = PORT_INT_LOGIC_ZERO;
189		break;
190	case IRQ_TYPE_LEVEL_HIGH:
191		irqc = PORT_INT_LOGIC_ONE;
192		break;
193	default:
194		return -EINVAL;
195	}
196
197	port->irqc[d->hwirq] = irqc;
198
199	if (type & IRQ_TYPE_LEVEL_MASK)
200		irq_set_handler_locked(d, handle_level_irq);
201	else
202		irq_set_handler_locked(d, handle_edge_irq);
203
204	return 0;
205}
206
207static void vf610_gpio_irq_mask(struct irq_data *d)
208{
209	struct vf610_gpio_port *port =
210		gpiochip_get_data(irq_data_get_irq_chip_data(d));
211	void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq);
212
213	vf610_gpio_writel(0, pcr_base);
214}
215
216static void vf610_gpio_irq_unmask(struct irq_data *d)
217{
218	struct vf610_gpio_port *port =
219		gpiochip_get_data(irq_data_get_irq_chip_data(d));
220	void __iomem *pcr_base = port->base + PORT_PCR(d->hwirq);
221
222	vf610_gpio_writel(port->irqc[d->hwirq] << PORT_PCR_IRQC_OFFSET,
223			  pcr_base);
224}
225
226static int vf610_gpio_irq_set_wake(struct irq_data *d, u32 enable)
227{
228	struct vf610_gpio_port *port =
229		gpiochip_get_data(irq_data_get_irq_chip_data(d));
230
231	if (enable)
232		enable_irq_wake(port->irq);
233	else
234		disable_irq_wake(port->irq);
235
236	return 0;
237}
238
239static void vf610_gpio_disable_clk(void *data)
240{
241	clk_disable_unprepare(data);
242}
243
244static int vf610_gpio_probe(struct platform_device *pdev)
245{
246	struct device *dev = &pdev->dev;
247	struct device_node *np = dev->of_node;
248	struct vf610_gpio_port *port;
249	struct gpio_chip *gc;
250	struct gpio_irq_chip *girq;
251	struct irq_chip *ic;
252	int i;
253	int ret;
254
255	port = devm_kzalloc(dev, sizeof(*port), GFP_KERNEL);
256	if (!port)
257		return -ENOMEM;
258
259	port->sdata = of_device_get_match_data(dev);
260	port->base = devm_platform_ioremap_resource(pdev, 0);
261	if (IS_ERR(port->base))
262		return PTR_ERR(port->base);
263
264	port->gpio_base = devm_platform_ioremap_resource(pdev, 1);
265	if (IS_ERR(port->gpio_base))
266		return PTR_ERR(port->gpio_base);
267
268	port->irq = platform_get_irq(pdev, 0);
269	if (port->irq < 0)
270		return port->irq;
271
272	port->clk_port = devm_clk_get(dev, "port");
273	ret = PTR_ERR_OR_ZERO(port->clk_port);
274	if (!ret) {
275		ret = clk_prepare_enable(port->clk_port);
276		if (ret)
277			return ret;
278		ret = devm_add_action_or_reset(dev, vf610_gpio_disable_clk,
279					       port->clk_port);
280		if (ret)
281			return ret;
282	} else if (ret == -EPROBE_DEFER) {
283		/*
284		 * Percolate deferrals, for anything else,
285		 * just live without the clocking.
286		 */
287		return ret;
288	}
289
290	port->clk_gpio = devm_clk_get(dev, "gpio");
291	ret = PTR_ERR_OR_ZERO(port->clk_gpio);
292	if (!ret) {
293		ret = clk_prepare_enable(port->clk_gpio);
294		if (ret)
295			return ret;
296		ret = devm_add_action_or_reset(dev, vf610_gpio_disable_clk,
297					       port->clk_gpio);
298		if (ret)
299			return ret;
300	} else if (ret == -EPROBE_DEFER) {
301		return ret;
302	}
303
304	gc = &port->gc;
305	gc->of_node = np;
306	gc->parent = dev;
307	gc->label = dev_name(dev);
308	gc->ngpio = VF610_GPIO_PER_PORT;
309	gc->base = of_alias_get_id(np, "gpio") * VF610_GPIO_PER_PORT;
310
311	gc->request = gpiochip_generic_request;
312	gc->free = gpiochip_generic_free;
313	gc->direction_input = vf610_gpio_direction_input;
314	gc->get = vf610_gpio_get;
315	gc->direction_output = vf610_gpio_direction_output;
316	gc->set = vf610_gpio_set;
317
318	ic = &port->ic;
319	ic->name = "gpio-vf610";
320	ic->irq_ack = vf610_gpio_irq_ack;
321	ic->irq_mask = vf610_gpio_irq_mask;
322	ic->irq_unmask = vf610_gpio_irq_unmask;
323	ic->irq_set_type = vf610_gpio_irq_set_type;
324	ic->irq_set_wake = vf610_gpio_irq_set_wake;
325
326	/* Mask all GPIO interrupts */
327	for (i = 0; i < gc->ngpio; i++)
328		vf610_gpio_writel(0, port->base + PORT_PCR(i));
329
330	/* Clear the interrupt status register for all GPIO's */
331	vf610_gpio_writel(~0, port->base + PORT_ISFR);
332
333	girq = &gc->irq;
334	girq->chip = ic;
335	girq->parent_handler = vf610_gpio_irq_handler;
336	girq->num_parents = 1;
337	girq->parents = devm_kcalloc(&pdev->dev, 1,
338				     sizeof(*girq->parents),
339				     GFP_KERNEL);
340	if (!girq->parents)
341		return -ENOMEM;
342	girq->parents[0] = port->irq;
343	girq->default_type = IRQ_TYPE_NONE;
344	girq->handler = handle_edge_irq;
345
346	return devm_gpiochip_add_data(dev, gc, port);
347}
348
349static struct platform_driver vf610_gpio_driver = {
350	.driver		= {
351		.name	= "gpio-vf610",
352		.of_match_table = vf610_gpio_dt_ids,
353	},
354	.probe		= vf610_gpio_probe,
355};
356
357builtin_platform_driver(vf610_gpio_driver);
358