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