gpio.c revision 0b73ee5d534cc6dcb96efb9eac4cf96b40910911 
1/*
2 * SuperH Pin Function Controller GPIO driver.
3 *
4 * Copyright (C) 2008 Magnus Damm
5 * Copyright (C) 2009 - 2012 Paul Mundt
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License.  See the file "COPYING" in the main directory of this archive
9 * for more details.
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME " gpio: " fmt
13
14#include <linux/device.h>
15#include <linux/gpio.h>
16#include <linux/init.h>
17#include <linux/module.h>
18#include <linux/pinctrl/consumer.h>
19#include <linux/slab.h>
20#include <linux/spinlock.h>
21
22#include "core.h"
23
24struct sh_pfc_chip {
25	struct sh_pfc		*pfc;
26	struct gpio_chip	gpio_chip;
27};
28
29static struct sh_pfc_chip *gpio_to_pfc_chip(struct gpio_chip *gc)
30{
31	return container_of(gc, struct sh_pfc_chip, gpio_chip);
32}
33
34static struct sh_pfc *gpio_to_pfc(struct gpio_chip *gc)
35{
36	return gpio_to_pfc_chip(gc)->pfc;
37}
38
39/* -----------------------------------------------------------------------------
40 * Pin GPIOs
41 */
42
43static int gpio_pin_request(struct gpio_chip *gc, unsigned offset)
44{
45	struct sh_pfc *pfc = gpio_to_pfc(gc);
46
47	if (pfc->info->pins[offset].enum_id == 0)
48		return -EINVAL;
49
50	return pinctrl_request_gpio(offset);
51}
52
53static void gpio_pin_free(struct gpio_chip *gc, unsigned offset)
54{
55	return pinctrl_free_gpio(offset);
56}
57
58static void gpio_pin_set_value(struct sh_pfc *pfc, unsigned offset, int value)
59{
60	struct pinmux_data_reg *dr;
61	int bit;
62
63	sh_pfc_get_data_reg(pfc, offset, &dr, &bit);
64	sh_pfc_write_bit(dr, bit, value);
65}
66
67static int gpio_pin_direction_input(struct gpio_chip *gc, unsigned offset)
68{
69	return pinctrl_gpio_direction_input(offset);
70}
71
72static int gpio_pin_direction_output(struct gpio_chip *gc, unsigned offset,
73				    int value)
74{
75	gpio_pin_set_value(gpio_to_pfc(gc), offset, value);
76
77	return pinctrl_gpio_direction_output(offset);
78}
79
80static int gpio_pin_get(struct gpio_chip *gc, unsigned offset)
81{
82	struct sh_pfc *pfc = gpio_to_pfc(gc);
83	struct pinmux_data_reg *dr;
84	int bit;
85
86	sh_pfc_get_data_reg(pfc, offset, &dr, &bit);
87	return sh_pfc_read_bit(dr, bit);
88}
89
90static void gpio_pin_set(struct gpio_chip *gc, unsigned offset, int value)
91{
92	gpio_pin_set_value(gpio_to_pfc(gc), offset, value);
93}
94
95static int gpio_pin_to_irq(struct gpio_chip *gc, unsigned offset)
96{
97	struct sh_pfc *pfc = gpio_to_pfc(gc);
98	int i, k;
99
100	for (i = 0; i < pfc->info->gpio_irq_size; i++) {
101		unsigned short *gpios = pfc->info->gpio_irq[i].gpios;
102
103		for (k = 0; gpios[k]; k++) {
104			if (gpios[k] == offset)
105				return pfc->info->gpio_irq[i].irq;
106		}
107	}
108
109	return -ENOSYS;
110}
111
112static void gpio_pin_setup(struct sh_pfc_chip *chip)
113{
114	struct sh_pfc *pfc = chip->pfc;
115	struct gpio_chip *gc = &chip->gpio_chip;
116
117	gc->request = gpio_pin_request;
118	gc->free = gpio_pin_free;
119	gc->direction_input = gpio_pin_direction_input;
120	gc->get = gpio_pin_get;
121	gc->direction_output = gpio_pin_direction_output;
122	gc->set = gpio_pin_set;
123	gc->to_irq = gpio_pin_to_irq;
124
125	gc->label = pfc->info->name;
126	gc->dev = pfc->dev;
127	gc->owner = THIS_MODULE;
128	gc->base = 0;
129	gc->ngpio = pfc->info->nr_pins;
130}
131
132/* -----------------------------------------------------------------------------
133 * Function GPIOs
134 */
135
136static int gpio_function_request(struct gpio_chip *gc, unsigned offset)
137{
138	struct sh_pfc *pfc = gpio_to_pfc(gc);
139	unsigned int mark = pfc->info->func_gpios[offset].enum_id;
140	unsigned long flags;
141	int ret = -EINVAL;
142
143	pr_notice_once("Use of GPIO API for function requests is deprecated, convert to pinctrl\n");
144
145	if (mark == 0)
146		return ret;
147
148	spin_lock_irqsave(&pfc->lock, flags);
149
150	if (sh_pfc_config_mux(pfc, mark, PINMUX_TYPE_FUNCTION, GPIO_CFG_DRYRUN))
151		goto done;
152
153	if (sh_pfc_config_mux(pfc, mark, PINMUX_TYPE_FUNCTION, GPIO_CFG_REQ))
154		goto done;
155
156	ret = 0;
157
158done:
159	spin_unlock_irqrestore(&pfc->lock, flags);
160	return ret;
161}
162
163static void gpio_function_free(struct gpio_chip *gc, unsigned offset)
164{
165	struct sh_pfc *pfc = gpio_to_pfc(gc);
166	unsigned int mark = pfc->info->func_gpios[offset].enum_id;
167	unsigned long flags;
168
169	spin_lock_irqsave(&pfc->lock, flags);
170
171	sh_pfc_config_mux(pfc, mark, PINMUX_TYPE_FUNCTION, GPIO_CFG_FREE);
172
173	spin_unlock_irqrestore(&pfc->lock, flags);
174}
175
176static void gpio_function_setup(struct sh_pfc_chip *chip)
177{
178	struct sh_pfc *pfc = chip->pfc;
179	struct gpio_chip *gc = &chip->gpio_chip;
180
181	gc->request = gpio_function_request;
182	gc->free = gpio_function_free;
183
184	gc->label = pfc->info->name;
185	gc->owner = THIS_MODULE;
186	gc->base = pfc->info->nr_pins;
187	gc->ngpio = pfc->info->nr_func_gpios;
188}
189
190/* -----------------------------------------------------------------------------
191 * Register/unregister
192 */
193
194static struct sh_pfc_chip *
195sh_pfc_add_gpiochip(struct sh_pfc *pfc, void(*setup)(struct sh_pfc_chip *))
196{
197	struct sh_pfc_chip *chip;
198	int ret;
199
200	chip = devm_kzalloc(pfc->dev, sizeof(*chip), GFP_KERNEL);
201	if (unlikely(!chip))
202		return ERR_PTR(-ENOMEM);
203
204	chip->pfc = pfc;
205
206	setup(chip);
207
208	ret = gpiochip_add(&chip->gpio_chip);
209	if (unlikely(ret < 0))
210		return ERR_PTR(ret);
211
212	pr_info("%s handling gpio %u -> %u\n",
213		chip->gpio_chip.label, chip->gpio_chip.base,
214		chip->gpio_chip.base + chip->gpio_chip.ngpio - 1);
215
216	return chip;
217}
218
219int sh_pfc_register_gpiochip(struct sh_pfc *pfc)
220{
221	struct sh_pfc_chip *chip;
222
223	chip = sh_pfc_add_gpiochip(pfc, gpio_pin_setup);
224	if (IS_ERR(chip))
225		return PTR_ERR(chip);
226
227	pfc->gpio = chip;
228
229	chip = sh_pfc_add_gpiochip(pfc, gpio_function_setup);
230	if (IS_ERR(chip))
231		return PTR_ERR(chip);
232
233	pfc->func = chip;
234
235	return 0;
236}
237
238int sh_pfc_unregister_gpiochip(struct sh_pfc *pfc)
239{
240	int err;
241	int ret;
242
243	ret = gpiochip_remove(&pfc->gpio->gpio_chip);
244	err = gpiochip_remove(&pfc->func->gpio_chip);
245
246	return ret < 0 ? ret : err;
247}
248