treewide: gpio-export: add error handling
[openwrt/staging/stintel.git] / target / linux / lantiq / patches-4.14 / 0030-GPIO-add-named-gpio-exports.patch
1 From cc809a441d8f2924f785eb863dfa6aef47a25b0b Mon Sep 17 00:00:00 2001
2 From: John Crispin <blogic@openwrt.org>
3 Date: Tue, 12 Aug 2014 20:49:27 +0200
4 Subject: [PATCH 30/36] GPIO: add named gpio exports
5
6 Signed-off-by: John Crispin <blogic@openwrt.org>
7 ---
8 drivers/gpio/gpiolib-of.c | 68 +++++++++++++++++++++++++++++++++++++++++
9 drivers/gpio/gpiolib.c | 11 +++++--
10 include/asm-generic/gpio.h | 5 +++
11 include/linux/gpio/consumer.h | 8 +++++
12 4 files changed, 90 insertions(+), 2 deletions(-)
13
14 --- a/drivers/gpio/gpiolib-of.c
15 +++ b/drivers/gpio/gpiolib-of.c
16 @@ -23,6 +23,8 @@
17 #include <linux/pinctrl/pinctrl.h>
18 #include <linux/slab.h>
19 #include <linux/gpio/machine.h>
20 +#include <linux/init.h>
21 +#include <linux/platform_device.h>
22
23 #include "gpiolib.h"
24
25 @@ -506,3 +508,75 @@ void of_gpiochip_remove(struct gpio_chip
26 gpiochip_remove_pin_ranges(chip);
27 of_node_put(chip->of_node);
28 }
29 +
30 +#ifdef CONFIG_GPIO_SYSFS
31 +
32 +static struct of_device_id gpio_export_ids[] = {
33 + { .compatible = "gpio-export" },
34 + { /* sentinel */ }
35 +};
36 +
37 +static int __init of_gpio_export_probe(struct platform_device *pdev)
38 +{
39 + struct device_node *np = pdev->dev.of_node;
40 + struct device_node *cnp;
41 + u32 val;
42 + int nb = 0;
43 +
44 + for_each_child_of_node(np, cnp) {
45 + const char *name = NULL;
46 + int gpio;
47 + bool dmc;
48 + int max_gpio = 1;
49 + int i;
50 +
51 + of_property_read_string(cnp, "gpio-export,name", &name);
52 +
53 + if (!name)
54 + max_gpio = of_gpio_count(cnp);
55 +
56 + for (i = 0; i < max_gpio; i++) {
57 + unsigned flags = 0;
58 + enum of_gpio_flags of_flags;
59 +
60 + gpio = of_get_gpio_flags(cnp, i, &of_flags);
61 + if (!gpio_is_valid(gpio))
62 + return gpio;
63 +
64 + if (of_flags == OF_GPIO_ACTIVE_LOW)
65 + flags |= GPIOF_ACTIVE_LOW;
66 +
67 + if (!of_property_read_u32(cnp, "gpio-export,output", &val))
68 + flags |= val ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
69 + else
70 + flags |= GPIOF_IN;
71 +
72 + if (devm_gpio_request_one(&pdev->dev, gpio, flags, name ? name : of_node_full_name(np)))
73 + continue;
74 +
75 + dmc = of_property_read_bool(cnp, "gpio-export,direction_may_change");
76 + gpio_export_with_name(gpio, dmc, name);
77 + nb++;
78 + }
79 + }
80 +
81 + dev_info(&pdev->dev, "%d gpio(s) exported\n", nb);
82 +
83 + return 0;
84 +}
85 +
86 +static struct platform_driver gpio_export_driver = {
87 + .driver = {
88 + .name = "gpio-export",
89 + .owner = THIS_MODULE,
90 + .of_match_table = of_match_ptr(gpio_export_ids),
91 + },
92 +};
93 +
94 +static int __init of_gpio_export_init(void)
95 +{
96 + return platform_driver_probe(&gpio_export_driver, of_gpio_export_probe);
97 +}
98 +device_initcall(of_gpio_export_init);
99 +
100 +#endif
101 --- a/include/asm-generic/gpio.h
102 +++ b/include/asm-generic/gpio.h
103 @@ -127,6 +127,12 @@ static inline int gpio_export(unsigned g
104 return gpiod_export(gpio_to_desc(gpio), direction_may_change);
105 }
106
107 +int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
108 +static inline int gpio_export_with_name(unsigned gpio, bool direction_may_change, const char *name)
109 +{
110 + return __gpiod_export(gpio_to_desc(gpio), direction_may_change, name);
111 +}
112 +
113 static inline int gpio_export_link(struct device *dev, const char *name,
114 unsigned gpio)
115 {
116 --- a/include/linux/gpio/consumer.h
117 +++ b/include/linux/gpio/consumer.h
118 @@ -451,6 +451,7 @@ struct gpio_desc *devm_fwnode_get_gpiod_
119
120 #if IS_ENABLED(CONFIG_GPIOLIB) && IS_ENABLED(CONFIG_GPIO_SYSFS)
121
122 +int _gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name);
123 int gpiod_export(struct gpio_desc *desc, bool direction_may_change);
124 int gpiod_export_link(struct device *dev, const char *name,
125 struct gpio_desc *desc);
126 @@ -458,6 +459,13 @@ void gpiod_unexport(struct gpio_desc *de
127
128 #else /* CONFIG_GPIOLIB && CONFIG_GPIO_SYSFS */
129
130 +static inline int _gpiod_export(struct gpio_desc *desc,
131 + bool direction_may_change,
132 + const char *name)
133 +{
134 + return -ENOSYS;
135 +}
136 +
137 static inline int gpiod_export(struct gpio_desc *desc,
138 bool direction_may_change)
139 {
140 --- a/drivers/gpio/gpiolib-sysfs.c
141 +++ b/drivers/gpio/gpiolib-sysfs.c
142 @@ -553,7 +553,7 @@ static struct class gpio_class = {
143 *
144 * Returns zero on success, else an error.
145 */
146 -int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
147 +int __gpiod_export(struct gpio_desc *desc, bool direction_may_change, const char *name)
148 {
149 struct gpio_chip *chip;
150 struct gpio_device *gdev;
151 @@ -615,6 +615,8 @@ int gpiod_export(struct gpio_desc *desc,
152 offset = gpio_chip_hwgpio(desc);
153 if (chip->names && chip->names[offset])
154 ioname = chip->names[offset];
155 + if (name)
156 + ioname = name;
157
158 dev = device_create_with_groups(&gpio_class, &gdev->dev,
159 MKDEV(0, 0), data, gpio_groups,
160 @@ -636,6 +638,12 @@ err_unlock:
161 gpiod_dbg(desc, "%s: status %d\n", __func__, status);
162 return status;
163 }
164 +EXPORT_SYMBOL_GPL(__gpiod_export);
165 +
166 +int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
167 +{
168 + return __gpiod_export(desc, direction_may_change, NULL);
169 +}
170 EXPORT_SYMBOL_GPL(gpiod_export);
171
172 static int match_export(struct device *dev, const void *desc)