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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Generic GPIO card-detect helper
4 *
5 * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
6 */
7
8#include <linux/err.h>
9#include <linux/gpio/consumer.h>
10#include <linux/interrupt.h>
11#include <linux/jiffies.h>
12#include <linux/mmc/host.h>
13#include <linux/mmc/slot-gpio.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16
17#include "slot-gpio.h"
18
19struct mmc_gpio {
20 struct gpio_desc *ro_gpio;
21 struct gpio_desc *cd_gpio;
22 irqreturn_t (*cd_gpio_isr)(int irq, void *dev_id);
23 char *ro_label;
24 char *cd_label;
25 u32 cd_debounce_delay_ms;
26};
27
28static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
29{
30 /* Schedule a card detection after a debounce timeout */
31 struct mmc_host *host = dev_id;
32 struct mmc_gpio *ctx = host->slot.handler_priv;
33
34 host->trigger_card_event = true;
35 mmc_detect_change(host, msecs_to_jiffies(ctx->cd_debounce_delay_ms));
36
37 return IRQ_HANDLED;
38}
39
40int mmc_gpio_alloc(struct mmc_host *host)
41{
42 const char *devname = dev_name(host->parent);
43 struct mmc_gpio *ctx;
44
45 ctx = devm_kzalloc(host->parent, sizeof(*ctx), GFP_KERNEL);
46 if (!ctx)
47 return -ENOMEM;
48
49 ctx->cd_debounce_delay_ms = 200;
50 ctx->cd_label = devm_kasprintf(host->parent, GFP_KERNEL, "%s cd", devname);
51 if (!ctx->cd_label)
52 return -ENOMEM;
53 ctx->ro_label = devm_kasprintf(host->parent, GFP_KERNEL, "%s ro", devname);
54 if (!ctx->ro_label)
55 return -ENOMEM;
56 host->slot.handler_priv = ctx;
57 host->slot.cd_irq = -EINVAL;
58
59 return 0;
60}
61
62int mmc_gpio_get_ro(struct mmc_host *host)
63{
64 struct mmc_gpio *ctx = host->slot.handler_priv;
65
66 if (!ctx || !ctx->ro_gpio)
67 return -ENOSYS;
68
69 return gpiod_get_value_cansleep(ctx->ro_gpio);
70}
71EXPORT_SYMBOL(mmc_gpio_get_ro);
72
73int mmc_gpio_get_cd(struct mmc_host *host)
74{
75 struct mmc_gpio *ctx = host->slot.handler_priv;
76 int cansleep;
77
78 if (!ctx || !ctx->cd_gpio)
79 return -ENOSYS;
80
81 cansleep = gpiod_cansleep(ctx->cd_gpio);
82 return cansleep ?
83 gpiod_get_value_cansleep(ctx->cd_gpio) :
84 gpiod_get_value(ctx->cd_gpio);
85}
86EXPORT_SYMBOL(mmc_gpio_get_cd);
87
88void mmc_gpiod_request_cd_irq(struct mmc_host *host)
89{
90 struct mmc_gpio *ctx = host->slot.handler_priv;
91 int irq = -EINVAL;
92 int ret;
93
94 if (host->slot.cd_irq >= 0 || !ctx || !ctx->cd_gpio)
95 return;
96
97 /*
98 * Do not use IRQ if the platform prefers to poll, e.g., because that
99 * IRQ number is already used by another unit and cannot be shared.
100 */
101 if (!(host->caps & MMC_CAP_NEEDS_POLL))
102 irq = gpiod_to_irq(ctx->cd_gpio);
103
104 if (irq >= 0) {
105 if (!ctx->cd_gpio_isr)
106 ctx->cd_gpio_isr = mmc_gpio_cd_irqt;
107 ret = devm_request_threaded_irq(host->parent, irq,
108 NULL, ctx->cd_gpio_isr,
109 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
110 ctx->cd_label, host);
111 if (ret < 0)
112 irq = ret;
113 }
114
115 host->slot.cd_irq = irq;
116
117 if (irq < 0)
118 host->caps |= MMC_CAP_NEEDS_POLL;
119}
120EXPORT_SYMBOL(mmc_gpiod_request_cd_irq);
121
122int mmc_gpio_set_cd_wake(struct mmc_host *host, bool on)
123{
124 int ret = 0;
125
126 if (!(host->caps & MMC_CAP_CD_WAKE) ||
127 host->slot.cd_irq < 0 ||
128 on == host->slot.cd_wake_enabled)
129 return 0;
130
131 if (on) {
132 ret = enable_irq_wake(host->slot.cd_irq);
133 host->slot.cd_wake_enabled = !ret;
134 } else {
135 disable_irq_wake(host->slot.cd_irq);
136 host->slot.cd_wake_enabled = false;
137 }
138
139 return ret;
140}
141EXPORT_SYMBOL(mmc_gpio_set_cd_wake);
142
143/* Register an alternate interrupt service routine for
144 * the card-detect GPIO.
145 */
146void mmc_gpio_set_cd_isr(struct mmc_host *host,
147 irqreturn_t (*isr)(int irq, void *dev_id))
148{
149 struct mmc_gpio *ctx = host->slot.handler_priv;
150
151 WARN_ON(ctx->cd_gpio_isr);
152 ctx->cd_gpio_isr = isr;
153}
154EXPORT_SYMBOL(mmc_gpio_set_cd_isr);
155
156/**
157 * mmc_gpiod_request_cd - request a gpio descriptor for card-detection
158 * @host: mmc host
159 * @con_id: function within the GPIO consumer
160 * @idx: index of the GPIO to obtain in the consumer
161 * @override_active_level: ignore %GPIO_ACTIVE_LOW flag
162 * @debounce: debounce time in microseconds
163 *
164 * Note that this must be called prior to mmc_add_host()
165 * otherwise the caller must also call mmc_gpiod_request_cd_irq().
166 *
167 * Returns zero on success, else an error.
168 */
169int mmc_gpiod_request_cd(struct mmc_host *host, const char *con_id,
170 unsigned int idx, bool override_active_level,
171 unsigned int debounce)
172{
173 struct mmc_gpio *ctx = host->slot.handler_priv;
174 struct gpio_desc *desc;
175 int ret;
176
177 desc = devm_gpiod_get_index(host->parent, con_id, idx, GPIOD_IN);
178 if (IS_ERR(desc))
179 return PTR_ERR(desc);
180
181 /* Update default label if no con_id provided */
182 if (!con_id)
183 gpiod_set_consumer_name(desc, ctx->cd_label);
184
185 if (debounce) {
186 ret = gpiod_set_debounce(desc, debounce);
187 if (ret < 0)
188 ctx->cd_debounce_delay_ms = debounce / 1000;
189 }
190
191 /* override forces default (active-low) polarity ... */
192 if (override_active_level && !gpiod_is_active_low(desc))
193 gpiod_toggle_active_low(desc);
194
195 /* ... or active-high */
196 if (host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH)
197 gpiod_toggle_active_low(desc);
198
199 ctx->cd_gpio = desc;
200
201 return 0;
202}
203EXPORT_SYMBOL(mmc_gpiod_request_cd);
204
205bool mmc_can_gpio_cd(struct mmc_host *host)
206{
207 struct mmc_gpio *ctx = host->slot.handler_priv;
208
209 return ctx->cd_gpio ? true : false;
210}
211EXPORT_SYMBOL(mmc_can_gpio_cd);
212
213/**
214 * mmc_gpiod_request_ro - request a gpio descriptor for write protection
215 * @host: mmc host
216 * @con_id: function within the GPIO consumer
217 * @idx: index of the GPIO to obtain in the consumer
218 * @debounce: debounce time in microseconds
219 *
220 * Returns zero on success, else an error.
221 */
222int mmc_gpiod_request_ro(struct mmc_host *host, const char *con_id,
223 unsigned int idx, unsigned int debounce)
224{
225 struct mmc_gpio *ctx = host->slot.handler_priv;
226 struct gpio_desc *desc;
227 int ret;
228
229 desc = devm_gpiod_get_index(host->parent, con_id, idx, GPIOD_IN);
230 if (IS_ERR(desc))
231 return PTR_ERR(desc);
232
233 /* Update default label if no con_id provided */
234 if (!con_id)
235 gpiod_set_consumer_name(desc, ctx->ro_label);
236
237 if (debounce) {
238 ret = gpiod_set_debounce(desc, debounce);
239 if (ret < 0)
240 return ret;
241 }
242
243 if (host->caps2 & MMC_CAP2_RO_ACTIVE_HIGH)
244 gpiod_toggle_active_low(desc);
245
246 ctx->ro_gpio = desc;
247
248 return 0;
249}
250EXPORT_SYMBOL(mmc_gpiod_request_ro);
251
252bool mmc_can_gpio_ro(struct mmc_host *host)
253{
254 struct mmc_gpio *ctx = host->slot.handler_priv;
255
256 return ctx->ro_gpio ? true : false;
257}
258EXPORT_SYMBOL(mmc_can_gpio_ro);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Generic GPIO card-detect helper
4 *
5 * Copyright (C) 2011, Guennadi Liakhovetski <g.liakhovetski@gmx.de>
6 */
7
8#include <linux/err.h>
9#include <linux/gpio/consumer.h>
10#include <linux/interrupt.h>
11#include <linux/jiffies.h>
12#include <linux/mmc/host.h>
13#include <linux/mmc/slot-gpio.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16
17#include "slot-gpio.h"
18
19struct mmc_gpio {
20 struct gpio_desc *ro_gpio;
21 struct gpio_desc *cd_gpio;
22 bool override_cd_active_level;
23 irqreturn_t (*cd_gpio_isr)(int irq, void *dev_id);
24 char *ro_label;
25 char *cd_label;
26 u32 cd_debounce_delay_ms;
27};
28
29static irqreturn_t mmc_gpio_cd_irqt(int irq, void *dev_id)
30{
31 /* Schedule a card detection after a debounce timeout */
32 struct mmc_host *host = dev_id;
33 struct mmc_gpio *ctx = host->slot.handler_priv;
34
35 host->trigger_card_event = true;
36 mmc_detect_change(host, msecs_to_jiffies(ctx->cd_debounce_delay_ms));
37
38 return IRQ_HANDLED;
39}
40
41int mmc_gpio_alloc(struct mmc_host *host)
42{
43 struct mmc_gpio *ctx = devm_kzalloc(host->parent,
44 sizeof(*ctx), GFP_KERNEL);
45
46 if (ctx) {
47 ctx->cd_debounce_delay_ms = 200;
48 ctx->cd_label = devm_kasprintf(host->parent, GFP_KERNEL,
49 "%s cd", dev_name(host->parent));
50 if (!ctx->cd_label)
51 return -ENOMEM;
52 ctx->ro_label = devm_kasprintf(host->parent, GFP_KERNEL,
53 "%s ro", dev_name(host->parent));
54 if (!ctx->ro_label)
55 return -ENOMEM;
56 host->slot.handler_priv = ctx;
57 host->slot.cd_irq = -EINVAL;
58 }
59
60 return ctx ? 0 : -ENOMEM;
61}
62
63int mmc_gpio_get_ro(struct mmc_host *host)
64{
65 struct mmc_gpio *ctx = host->slot.handler_priv;
66
67 if (!ctx || !ctx->ro_gpio)
68 return -ENOSYS;
69
70 return gpiod_get_value_cansleep(ctx->ro_gpio);
71}
72EXPORT_SYMBOL(mmc_gpio_get_ro);
73
74int mmc_gpio_get_cd(struct mmc_host *host)
75{
76 struct mmc_gpio *ctx = host->slot.handler_priv;
77 int cansleep;
78
79 if (!ctx || !ctx->cd_gpio)
80 return -ENOSYS;
81
82 cansleep = gpiod_cansleep(ctx->cd_gpio);
83 if (ctx->override_cd_active_level) {
84 int value = cansleep ?
85 gpiod_get_raw_value_cansleep(ctx->cd_gpio) :
86 gpiod_get_raw_value(ctx->cd_gpio);
87 return !value ^ !!(host->caps2 & MMC_CAP2_CD_ACTIVE_HIGH);
88 }
89
90 return cansleep ?
91 gpiod_get_value_cansleep(ctx->cd_gpio) :
92 gpiod_get_value(ctx->cd_gpio);
93}
94EXPORT_SYMBOL(mmc_gpio_get_cd);
95
96void mmc_gpiod_request_cd_irq(struct mmc_host *host)
97{
98 struct mmc_gpio *ctx = host->slot.handler_priv;
99 int irq = -EINVAL;
100 int ret;
101
102 if (host->slot.cd_irq >= 0 || !ctx || !ctx->cd_gpio)
103 return;
104
105 /*
106 * Do not use IRQ if the platform prefers to poll, e.g., because that
107 * IRQ number is already used by another unit and cannot be shared.
108 */
109 if (!(host->caps & MMC_CAP_NEEDS_POLL))
110 irq = gpiod_to_irq(ctx->cd_gpio);
111
112 if (irq >= 0) {
113 if (!ctx->cd_gpio_isr)
114 ctx->cd_gpio_isr = mmc_gpio_cd_irqt;
115 ret = devm_request_threaded_irq(host->parent, irq,
116 NULL, ctx->cd_gpio_isr,
117 IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
118 ctx->cd_label, host);
119 if (ret < 0)
120 irq = ret;
121 }
122
123 host->slot.cd_irq = irq;
124
125 if (irq < 0)
126 host->caps |= MMC_CAP_NEEDS_POLL;
127}
128EXPORT_SYMBOL(mmc_gpiod_request_cd_irq);
129
130int mmc_gpio_set_cd_wake(struct mmc_host *host, bool on)
131{
132 int ret = 0;
133
134 if (!(host->caps & MMC_CAP_CD_WAKE) ||
135 host->slot.cd_irq < 0 ||
136 on == host->slot.cd_wake_enabled)
137 return 0;
138
139 if (on) {
140 ret = enable_irq_wake(host->slot.cd_irq);
141 host->slot.cd_wake_enabled = !ret;
142 } else {
143 disable_irq_wake(host->slot.cd_irq);
144 host->slot.cd_wake_enabled = false;
145 }
146
147 return ret;
148}
149EXPORT_SYMBOL(mmc_gpio_set_cd_wake);
150
151/* Register an alternate interrupt service routine for
152 * the card-detect GPIO.
153 */
154void mmc_gpio_set_cd_isr(struct mmc_host *host,
155 irqreturn_t (*isr)(int irq, void *dev_id))
156{
157 struct mmc_gpio *ctx = host->slot.handler_priv;
158
159 WARN_ON(ctx->cd_gpio_isr);
160 ctx->cd_gpio_isr = isr;
161}
162EXPORT_SYMBOL(mmc_gpio_set_cd_isr);
163
164/**
165 * mmc_gpiod_request_cd - request a gpio descriptor for card-detection
166 * @host: mmc host
167 * @con_id: function within the GPIO consumer
168 * @idx: index of the GPIO to obtain in the consumer
169 * @override_active_level: ignore %GPIO_ACTIVE_LOW flag
170 * @debounce: debounce time in microseconds
171 * @gpio_invert: will return whether the GPIO line is inverted or not, set
172 * to NULL to ignore
173 *
174 * Note that this must be called prior to mmc_add_host()
175 * otherwise the caller must also call mmc_gpiod_request_cd_irq().
176 *
177 * Returns zero on success, else an error.
178 */
179int mmc_gpiod_request_cd(struct mmc_host *host, const char *con_id,
180 unsigned int idx, bool override_active_level,
181 unsigned int debounce, bool *gpio_invert)
182{
183 struct mmc_gpio *ctx = host->slot.handler_priv;
184 struct gpio_desc *desc;
185 int ret;
186
187 desc = devm_gpiod_get_index(host->parent, con_id, idx, GPIOD_IN);
188 if (IS_ERR(desc))
189 return PTR_ERR(desc);
190
191 if (debounce) {
192 ret = gpiod_set_debounce(desc, debounce);
193 if (ret < 0)
194 ctx->cd_debounce_delay_ms = debounce / 1000;
195 }
196
197 if (gpio_invert)
198 *gpio_invert = !gpiod_is_active_low(desc);
199
200 ctx->override_cd_active_level = override_active_level;
201 ctx->cd_gpio = desc;
202
203 return 0;
204}
205EXPORT_SYMBOL(mmc_gpiod_request_cd);
206
207bool mmc_can_gpio_cd(struct mmc_host *host)
208{
209 struct mmc_gpio *ctx = host->slot.handler_priv;
210
211 return ctx->cd_gpio ? true : false;
212}
213EXPORT_SYMBOL(mmc_can_gpio_cd);
214
215/**
216 * mmc_gpiod_request_ro - request a gpio descriptor for write protection
217 * @host: mmc host
218 * @con_id: function within the GPIO consumer
219 * @idx: index of the GPIO to obtain in the consumer
220 * @debounce: debounce time in microseconds
221 * @gpio_invert: will return whether the GPIO line is inverted or not,
222 * set to NULL to ignore
223 *
224 * Returns zero on success, else an error.
225 */
226int mmc_gpiod_request_ro(struct mmc_host *host, const char *con_id,
227 unsigned int idx,
228 unsigned int debounce, bool *gpio_invert)
229{
230 struct mmc_gpio *ctx = host->slot.handler_priv;
231 struct gpio_desc *desc;
232 int ret;
233
234 desc = devm_gpiod_get_index(host->parent, con_id, idx, GPIOD_IN);
235 if (IS_ERR(desc))
236 return PTR_ERR(desc);
237
238 if (debounce) {
239 ret = gpiod_set_debounce(desc, debounce);
240 if (ret < 0)
241 return ret;
242 }
243
244 if (gpio_invert)
245 *gpio_invert = !gpiod_is_active_low(desc);
246
247 ctx->ro_gpio = desc;
248
249 return 0;
250}
251EXPORT_SYMBOL(mmc_gpiod_request_ro);
252
253bool mmc_can_gpio_ro(struct mmc_host *host)
254{
255 struct mmc_gpio *ctx = host->slot.handler_priv;
256
257 return ctx->ro_gpio ? true : false;
258}
259EXPORT_SYMBOL(mmc_can_gpio_ro);