Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Broadcom specific AMBA
3 * GPIO driver
4 *
5 * Copyright 2011, Broadcom Corporation
6 * Copyright 2012, Hauke Mehrtens <hauke@hauke-m.de>
7 *
8 * Licensed under the GNU/GPL. See COPYING for details.
9 */
10
11#include <linux/gpio/driver.h>
12#include <linux/interrupt.h>
13#include <linux/export.h>
14#include <linux/property.h>
15
16#include <linux/bcma/bcma.h>
17
18#include "bcma_private.h"
19
20#define BCMA_GPIO_MAX_PINS 32
21
22static int bcma_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
23{
24 struct bcma_drv_cc *cc = gpiochip_get_data(chip);
25
26 return !!bcma_chipco_gpio_in(cc, 1 << gpio);
27}
28
29static int bcma_gpio_set_value(struct gpio_chip *chip, unsigned int gpio,
30 int value)
31{
32 struct bcma_drv_cc *cc = gpiochip_get_data(chip);
33
34 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0);
35
36 return 0;
37}
38
39static int bcma_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
40{
41 struct bcma_drv_cc *cc = gpiochip_get_data(chip);
42
43 bcma_chipco_gpio_outen(cc, 1 << gpio, 0);
44 return 0;
45}
46
47static int bcma_gpio_direction_output(struct gpio_chip *chip, unsigned gpio,
48 int value)
49{
50 struct bcma_drv_cc *cc = gpiochip_get_data(chip);
51
52 bcma_chipco_gpio_outen(cc, 1 << gpio, 1 << gpio);
53 bcma_chipco_gpio_out(cc, 1 << gpio, value ? 1 << gpio : 0);
54 return 0;
55}
56
57static int bcma_gpio_request(struct gpio_chip *chip, unsigned gpio)
58{
59 struct bcma_drv_cc *cc = gpiochip_get_data(chip);
60
61 bcma_chipco_gpio_control(cc, 1 << gpio, 0);
62 /* clear pulldown */
63 bcma_chipco_gpio_pulldown(cc, 1 << gpio, 0);
64 /* Set pullup */
65 bcma_chipco_gpio_pullup(cc, 1 << gpio, 1 << gpio);
66
67 return 0;
68}
69
70static void bcma_gpio_free(struct gpio_chip *chip, unsigned gpio)
71{
72 struct bcma_drv_cc *cc = gpiochip_get_data(chip);
73
74 /* clear pullup */
75 bcma_chipco_gpio_pullup(cc, 1 << gpio, 0);
76}
77
78#if IS_BUILTIN(CONFIG_BCM47XX) || IS_BUILTIN(CONFIG_ARCH_BCM_5301X)
79
80static void bcma_gpio_irq_unmask(struct irq_data *d)
81{
82 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
83 struct bcma_drv_cc *cc = gpiochip_get_data(gc);
84 int gpio = irqd_to_hwirq(d);
85 u32 val = bcma_chipco_gpio_in(cc, BIT(gpio));
86
87 gpiochip_enable_irq(gc, gpio);
88 bcma_chipco_gpio_polarity(cc, BIT(gpio), val);
89 bcma_chipco_gpio_intmask(cc, BIT(gpio), BIT(gpio));
90}
91
92static void bcma_gpio_irq_mask(struct irq_data *d)
93{
94 struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
95 struct bcma_drv_cc *cc = gpiochip_get_data(gc);
96 int gpio = irqd_to_hwirq(d);
97
98 bcma_chipco_gpio_intmask(cc, BIT(gpio), 0);
99 gpiochip_disable_irq(gc, gpio);
100}
101
102static const struct irq_chip bcma_gpio_irq_chip = {
103 .name = "BCMA-GPIO",
104 .irq_mask = bcma_gpio_irq_mask,
105 .irq_unmask = bcma_gpio_irq_unmask,
106 .flags = IRQCHIP_IMMUTABLE,
107 GPIOCHIP_IRQ_RESOURCE_HELPERS,
108};
109
110static irqreturn_t bcma_gpio_irq_handler(int irq, void *dev_id)
111{
112 struct bcma_drv_cc *cc = dev_id;
113 struct gpio_chip *gc = &cc->gpio;
114 u32 val = bcma_cc_read32(cc, BCMA_CC_GPIOIN);
115 u32 mask = bcma_cc_read32(cc, BCMA_CC_GPIOIRQ);
116 u32 pol = bcma_cc_read32(cc, BCMA_CC_GPIOPOL);
117 unsigned long irqs = (val ^ pol) & mask;
118 int gpio;
119
120 if (!irqs)
121 return IRQ_NONE;
122
123 for_each_set_bit(gpio, &irqs, gc->ngpio)
124 generic_handle_domain_irq_safe(gc->irq.domain, gpio);
125 bcma_chipco_gpio_polarity(cc, irqs, val & irqs);
126
127 return IRQ_HANDLED;
128}
129
130static int bcma_gpio_irq_init(struct bcma_drv_cc *cc)
131{
132 struct gpio_chip *chip = &cc->gpio;
133 struct gpio_irq_chip *girq = &chip->irq;
134 int hwirq, err;
135
136 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC)
137 return 0;
138
139 hwirq = bcma_core_irq(cc->core, 0);
140 err = request_irq(hwirq, bcma_gpio_irq_handler, IRQF_SHARED, "gpio",
141 cc);
142 if (err)
143 return err;
144
145 bcma_chipco_gpio_intmask(cc, ~0, 0);
146 bcma_cc_set32(cc, BCMA_CC_IRQMASK, BCMA_CC_IRQ_GPIO);
147
148 gpio_irq_chip_set_chip(girq, &bcma_gpio_irq_chip);
149 /* This will let us handle the parent IRQ in the driver */
150 girq->parent_handler = NULL;
151 girq->num_parents = 0;
152 girq->parents = NULL;
153 girq->default_type = IRQ_TYPE_NONE;
154 girq->handler = handle_simple_irq;
155
156 return 0;
157}
158
159static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc)
160{
161 if (cc->core->bus->hosttype != BCMA_HOSTTYPE_SOC)
162 return;
163
164 bcma_cc_mask32(cc, BCMA_CC_IRQMASK, ~BCMA_CC_IRQ_GPIO);
165 free_irq(bcma_core_irq(cc->core, 0), cc);
166}
167#else
168static int bcma_gpio_irq_init(struct bcma_drv_cc *cc)
169{
170 return 0;
171}
172
173static void bcma_gpio_irq_exit(struct bcma_drv_cc *cc)
174{
175}
176#endif
177
178int bcma_gpio_init(struct bcma_drv_cc *cc)
179{
180 struct bcma_bus *bus = cc->core->bus;
181 struct gpio_chip *chip = &cc->gpio;
182 int err;
183
184 chip->label = "bcma_gpio";
185 chip->owner = THIS_MODULE;
186 chip->request = bcma_gpio_request;
187 chip->free = bcma_gpio_free;
188 chip->get = bcma_gpio_get_value;
189 chip->set = bcma_gpio_set_value;
190 chip->direction_input = bcma_gpio_direction_input;
191 chip->direction_output = bcma_gpio_direction_output;
192 chip->parent = bus->dev;
193 chip->fwnode = dev_fwnode(&cc->core->dev);
194
195 switch (bus->chipinfo.id) {
196 case BCMA_CHIP_ID_BCM4707:
197 case BCMA_CHIP_ID_BCM5357:
198 case BCMA_CHIP_ID_BCM53572:
199 case BCMA_CHIP_ID_BCM53573:
200 case BCMA_CHIP_ID_BCM47094:
201 chip->ngpio = 32;
202 break;
203 default:
204 chip->ngpio = 16;
205 }
206
207 /*
208 * Register SoC GPIO devices with absolute GPIO pin base.
209 * On MIPS, we don't have Device Tree and we can't use relative (per chip)
210 * GPIO numbers.
211 * On some ARM devices, user space may want to access some system GPIO
212 * pins directly, which is easier to do with a predictable GPIO base.
213 */
214 if (IS_BUILTIN(CONFIG_BCM47XX) ||
215 cc->core->bus->hosttype == BCMA_HOSTTYPE_SOC)
216 chip->base = bus->num * BCMA_GPIO_MAX_PINS;
217 else
218 chip->base = -1;
219
220 err = bcma_gpio_irq_init(cc);
221 if (err)
222 return err;
223
224 err = gpiochip_add_data(chip, cc);
225 if (err) {
226 bcma_gpio_irq_exit(cc);
227 return err;
228 }
229
230 return 0;
231}
232
233int bcma_gpio_unregister(struct bcma_drv_cc *cc)
234{
235 bcma_gpio_irq_exit(cc);
236 gpiochip_remove(&cc->gpio);
237 return 0;
238}