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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
leds: add LED driver for EL15203000 board
This patch adds a LED class driver for the LEDs found on
the Crane Merchandising System EL15203000 LEDs board
(aka RED LEDs board).
Signed-off-by: Oleh Kravchenko <oleg@kaa.org.ua>
Reviewed-by: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
authored by
Oleh Kravchenko
and committed by
Pavel
fc19967b
a788f6f2
+510
+139
Documentation/ABI/testing/sysfs-class-led-driver-el15203000
+139
Documentation/ABI/testing/sysfs-class-led-driver-el15203000
···
1
+
What: /sys/class/leds/<led>/hw_pattern
2
+
Date: September 2019
3
+
KernelVersion: 5.5
4
+
Description:
5
+
Specify a hardware pattern for the EL15203000 LED.
6
+
The LEDs board supports only predefined patterns by firmware
7
+
for specific LEDs.
8
+
9
+
Breathing mode for Screen frame light tube:
10
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"0 4000 1 4000"
11
+
12
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^
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+
|
14
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Max-| ---
15
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| / \
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+
| / \
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+
| / \ /
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+
| / \ /
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Min-|- ---
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|
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0------4------8--> time (sec)
22
+
23
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Cascade mode for Pipe LED:
24
+
"1 800 2 800 4 800 8 800 16 800"
25
+
26
+
^
27
+
|
28
+
0 On -|----+ +----+ +---
29
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| | | | |
30
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Off-| +-------------------+ +-------------------+
31
+
|
32
+
1 On -| +----+ +----+
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+
| | | | |
34
+
Off |----+ +-------------------+ +------------------
35
+
|
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+
2 On -| +----+ +----+
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+
| | | | |
38
+
Off-|---------+ +-------------------+ +-------------
39
+
|
40
+
3 On -| +----+ +----+
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+
| | | | |
42
+
Off-|--------------+ +-------------------+ +--------
43
+
|
44
+
4 On -| +----+ +----+
45
+
| | | | |
46
+
Off-|-------------------+ +-------------------+ +---
47
+
|
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0---0.8--1.6--2.4--3.2---4---4.8--5.6--6.4--7.2---8--> time (sec)
49
+
50
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Inverted cascade mode for Pipe LED:
51
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"30 800 29 800 27 800 23 800 15 800"
52
+
53
+
^
54
+
|
55
+
0 On -| +-------------------+ +-------------------+
56
+
| | | | |
57
+
Off-|----+ +----+ +---
58
+
|
59
+
1 On -|----+ +-------------------+ +------------------
60
+
| | | | |
61
+
Off | +----+ +----+
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+
|
63
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2 On -|---------+ +-------------------+ +-------------
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+
| | | | |
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Off-| +----+ +----+
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+
|
67
+
3 On -|--------------+ +-------------------+ +--------
68
+
| | | | |
69
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Off-| +----+ +----+
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+
|
71
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4 On -|-------------------+ +-------------------+ +---
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| | | | |
73
+
Off-| +----+ +----+
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+
|
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0---0.8--1.6--2.4--3.2---4---4.8--5.6--6.4--7.2---8--> time (sec)
76
+
77
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Bounce mode for Pipe LED:
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"1 800 2 800 4 800 8 800 16 800 16 800 8 800 4 800 2 800 1 800"
79
+
80
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^
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+
|
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0 On -|----+ +--------
83
+
| | |
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Off-| +---------------------------------------+
85
+
|
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1 On -| +----+ +----+
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+
| | | | |
88
+
Off |----+ +-----------------------------+ +--------
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+
|
90
+
2 On -| +----+ +----+
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+
| | | | |
92
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Off-|---------+ +-------------------+ +-------------
93
+
|
94
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3 On -| +----+ +----+
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+
| | | | |
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+
Off-|--------------+ +---------+ +------------------
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+
|
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4 On -| +---------+
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+
| | |
100
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Off-|-------------------+ +-----------------------
101
+
|
102
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0---0.8--1.6--2.4--3.2---4---4.8--5.6--6.4--7.2---8--> time (sec)
103
+
104
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Inverted bounce mode for Pipe LED:
105
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"30 800 29 800 27 800 23 800 15 800 15 800 23 800 27 800 29 800 30 800"
106
+
107
+
^
108
+
|
109
+
0 On -| +---------------------------------------+
110
+
| | |
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+
Off-|----+ +--------
112
+
|
113
+
1 On -|----+ +-----------------------------+ +--------
114
+
| | | | |
115
+
Off | +----+ +----+
116
+
|
117
+
2 On -|---------+ +-------------------+ +-------------
118
+
| | | | |
119
+
Off-| +----+ +----+
120
+
|
121
+
3 On -|--------------+ +---------+ +------------------
122
+
| | | | |
123
+
Off-| +----+ +----+
124
+
|
125
+
4 On -|-------------------+ +-----------------------
126
+
| | |
127
+
Off-| +---------+
128
+
|
129
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0---0.8--1.6--2.4--3.2---4---4.8--5.6--6.4--7.2---8--> time (sec)
130
+
131
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What: /sys/class/leds/<led>/repeat
132
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Date: September 2019
133
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KernelVersion: 5.5
134
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Description:
135
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EL15203000 supports only indefinitely patterns,
136
+
so this file should always store -1.
137
+
138
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For more info, please see:
139
+
Documentation/ABI/testing/sysfs-class-led-trigger-pattern
+13
drivers/leds/Kconfig
+13
drivers/leds/Kconfig
···
132
132
To compile this driver as a module, choose M here: the module
133
133
will be called leds-cr0014114.
134
134
135
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config LEDS_EL15203000
136
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tristate "LED Support for Crane EL15203000"
137
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depends on LEDS_CLASS
138
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depends on SPI
139
+
depends on OF
140
+
help
141
+
This option enables support for EL15203000 LED Board
142
+
(aka RED LED board) which is widely used in coffee vending
143
+
machines produced by Crane Merchandising Systems.
144
+
145
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To compile this driver as a module, choose M here: the module
146
+
will be called leds-el15203000.
147
+
135
148
config LEDS_LM3530
136
149
tristate "LCD Backlight driver for LM3530"
137
150
depends on LEDS_CLASS
+1
drivers/leds/Makefile
+1
drivers/leds/Makefile
+357
drivers/leds/leds-el15203000.c
+357
drivers/leds/leds-el15203000.c
···
1
+
// SPDX-License-Identifier: GPL-2.0
2
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// Copyright (c) 2019 Crane Merchandising Systems. All rights reserved.
3
+
// Copyright (C) 2019 Oleh Kravchenko <oleg@kaa.org.ua>
4
+
5
+
#include <linux/delay.h>
6
+
#include <linux/leds.h>
7
+
#include <linux/module.h>
8
+
#include <linux/of_device.h>
9
+
#include <linux/spi/spi.h>
10
+
11
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/*
12
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* EL15203000 SPI protocol description:
13
+
* +-----+---------+
14
+
* | LED | COMMAND |
15
+
* +-----+---------+
16
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* | 1 | 1 |
17
+
* +-----+---------+
18
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* (*) LEDs MCU board expects 20 msec delay per byte.
19
+
*
20
+
* LEDs:
21
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* +----------+--------------+-------------------------------------------+
22
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* | ID | NAME | DESCRIPTION |
23
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* +----------+--------------+-------------------------------------------+
24
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* | 'P' 0x50 | Pipe | Consists from 5 LEDs, controlled by board |
25
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* +----------+--------------+-------------------------------------------+
26
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* | 'S' 0x53 | Screen frame | Light tube around the screen |
27
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* +----------+--------------+-------------------------------------------+
28
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* | 'V' 0x56 | Vending area | Highlights a cup of coffee |
29
+
* +----------+--------------+-------------------------------------------+
30
+
*
31
+
* COMMAND:
32
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* +----------+-----------------+--------------+--------------+
33
+
* | VALUES | PIPE | SCREEN FRAME | VENDING AREA |
34
+
* +----------+-----------------+--------------+--------------+
35
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* | '0' 0x30 | Off |
36
+
* +----------+-----------------------------------------------+
37
+
* | '1' 0x31 | On |
38
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* +----------+-----------------+--------------+--------------+
39
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* | '2' 0x32 | Cascade | Breathing |
40
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* +----------+-----------------+--------------+
41
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* | '3' 0x33 | Inverse cascade |
42
+
* +----------+-----------------+
43
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* | '4' 0x34 | Bounce |
44
+
* +----------+-----------------+
45
+
* | '5' 0x35 | Inverse bounce |
46
+
* +----------+-----------------+
47
+
*/
48
+
49
+
/* EL15203000 default settings */
50
+
#define EL_FW_DELAY_USEC 20000ul
51
+
#define EL_PATTERN_DELAY_MSEC 800u
52
+
#define EL_PATTERN_LEN 10u
53
+
#define EL_PATTERN_HALF_LEN (EL_PATTERN_LEN / 2)
54
+
55
+
enum el15203000_command {
56
+
/* for all LEDs */
57
+
EL_OFF = '0',
58
+
EL_ON = '1',
59
+
60
+
/* for Screen LED */
61
+
EL_SCREEN_BREATHING = '2',
62
+
63
+
/* for Pipe LED */
64
+
EL_PIPE_CASCADE = '2',
65
+
EL_PIPE_INV_CASCADE = '3',
66
+
EL_PIPE_BOUNCE = '4',
67
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EL_PIPE_INV_BOUNCE = '5',
68
+
};
69
+
70
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struct el15203000_led {
71
+
struct el15203000 *priv;
72
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struct led_classdev ldev;
73
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u32 reg;
74
+
};
75
+
76
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struct el15203000 {
77
+
struct device *dev;
78
+
struct mutex lock;
79
+
struct spi_device *spi;
80
+
unsigned long delay;
81
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size_t count;
82
+
struct el15203000_led leds[];
83
+
};
84
+
85
+
static int el15203000_cmd(struct el15203000_led *led, u8 brightness)
86
+
{
87
+
int ret;
88
+
u8 cmd[2];
89
+
size_t i;
90
+
91
+
mutex_lock(&led->priv->lock);
92
+
93
+
dev_dbg(led->priv->dev, "Set brightness of 0x%02x(%c) to 0x%02x(%c)",
94
+
led->reg, led->reg, brightness, brightness);
95
+
96
+
/* to avoid SPI mistiming with firmware we should wait some time */
97
+
if (time_after(led->priv->delay, jiffies)) {
98
+
dev_dbg(led->priv->dev, "Wait %luus to sync",
99
+
EL_FW_DELAY_USEC);
100
+
101
+
usleep_range(EL_FW_DELAY_USEC,
102
+
EL_FW_DELAY_USEC + 1);
103
+
}
104
+
105
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cmd[0] = led->reg;
106
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cmd[1] = brightness;
107
+
108
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for (i = 0; i < ARRAY_SIZE(cmd); i++) {
109
+
if (i)
110
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usleep_range(EL_FW_DELAY_USEC,
111
+
EL_FW_DELAY_USEC + 1);
112
+
113
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ret = spi_write(led->priv->spi, &cmd[i], sizeof(cmd[i]));
114
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if (ret) {
115
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dev_err(led->priv->dev,
116
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"spi_write() error %d", ret);
117
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break;
118
+
}
119
+
}
120
+
121
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led->priv->delay = jiffies + usecs_to_jiffies(EL_FW_DELAY_USEC);
122
+
123
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mutex_unlock(&led->priv->lock);
124
+
125
+
return ret;
126
+
}
127
+
128
+
static int el15203000_set_blocking(struct led_classdev *ldev,
129
+
enum led_brightness brightness)
130
+
{
131
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struct el15203000_led *led = container_of(ldev,
132
+
struct el15203000_led,
133
+
ldev);
134
+
135
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return el15203000_cmd(led, brightness == LED_OFF ? EL_OFF : EL_ON);
136
+
}
137
+
138
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static int el15203000_pattern_set_S(struct led_classdev *ldev,
139
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struct led_pattern *pattern,
140
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u32 len, int repeat)
141
+
{
142
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struct el15203000_led *led = container_of(ldev,
143
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struct el15203000_led,
144
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ldev);
145
+
146
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if (repeat > 0 || len != 2 ||
147
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pattern[0].delta_t != 4000 || pattern[0].brightness != 0 ||
148
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pattern[1].delta_t != 4000 || pattern[1].brightness != 1)
149
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return -EINVAL;
150
+
151
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dev_dbg(led->priv->dev, "Breathing mode for 0x%02x(%c)",
152
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led->reg, led->reg);
153
+
154
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return el15203000_cmd(led, EL_SCREEN_BREATHING);
155
+
}
156
+
157
+
static bool is_cascade(const struct led_pattern *pattern, u32 len,
158
+
bool inv, bool right)
159
+
{
160
+
int val, t;
161
+
u32 i;
162
+
163
+
if (len != EL_PATTERN_HALF_LEN)
164
+
return false;
165
+
166
+
val = right ? BIT(4) : BIT(0);
167
+
168
+
for (i = 0; i < len; i++) {
169
+
t = inv ? ~val & GENMASK(4, 0) : val;
170
+
171
+
if (pattern[i].delta_t != EL_PATTERN_DELAY_MSEC ||
172
+
pattern[i].brightness != t)
173
+
return false;
174
+
175
+
val = right ? val >> 1 : val << 1;
176
+
}
177
+
178
+
return true;
179
+
}
180
+
181
+
static bool is_bounce(const struct led_pattern *pattern, u32 len, bool inv)
182
+
{
183
+
if (len != EL_PATTERN_LEN)
184
+
return false;
185
+
186
+
return is_cascade(pattern, EL_PATTERN_HALF_LEN, inv, false) &&
187
+
is_cascade(pattern + EL_PATTERN_HALF_LEN,
188
+
EL_PATTERN_HALF_LEN, inv, true);
189
+
}
190
+
191
+
static int el15203000_pattern_set_P(struct led_classdev *ldev,
192
+
struct led_pattern *pattern,
193
+
u32 len, int repeat)
194
+
{
195
+
u8 cmd;
196
+
struct el15203000_led *led = container_of(ldev,
197
+
struct el15203000_led,
198
+
ldev);
199
+
200
+
if (repeat > 0)
201
+
return -EINVAL;
202
+
203
+
if (is_cascade(pattern, len, false, false)) {
204
+
dev_dbg(led->priv->dev, "Cascade mode for 0x%02x(%c)",
205
+
led->reg, led->reg);
206
+
207
+
cmd = EL_PIPE_CASCADE;
208
+
} else if (is_cascade(pattern, len, true, false)) {
209
+
dev_dbg(led->priv->dev, "Inverse cascade mode for 0x%02x(%c)",
210
+
led->reg, led->reg);
211
+
212
+
cmd = EL_PIPE_INV_CASCADE;
213
+
} else if (is_bounce(pattern, len, false)) {
214
+
dev_dbg(led->priv->dev, "Bounce mode for 0x%02x(%c)",
215
+
led->reg, led->reg);
216
+
217
+
cmd = EL_PIPE_BOUNCE;
218
+
} else if (is_bounce(pattern, len, true)) {
219
+
dev_dbg(led->priv->dev, "Inverse bounce mode for 0x%02x(%c)",
220
+
led->reg, led->reg);
221
+
222
+
cmd = EL_PIPE_INV_BOUNCE;
223
+
} else {
224
+
dev_err(led->priv->dev, "Invalid hw_pattern for 0x%02x(%c)!",
225
+
led->reg, led->reg);
226
+
227
+
return -EINVAL;
228
+
}
229
+
230
+
return el15203000_cmd(led, cmd);
231
+
}
232
+
233
+
static int el15203000_pattern_clear(struct led_classdev *ldev)
234
+
{
235
+
struct el15203000_led *led = container_of(ldev,
236
+
struct el15203000_led,
237
+
ldev);
238
+
239
+
return el15203000_cmd(led, EL_OFF);
240
+
}
241
+
242
+
static int el15203000_probe_dt(struct el15203000 *priv)
243
+
{
244
+
struct el15203000_led *led = priv->leds;
245
+
struct fwnode_handle *child;
246
+
int ret;
247
+
248
+
device_for_each_child_node(priv->dev, child) {
249
+
struct led_init_data init_data = {};
250
+
251
+
ret = fwnode_property_read_u32(child, "reg", &led->reg);
252
+
if (ret) {
253
+
dev_err(priv->dev, "LED without ID number");
254
+
fwnode_handle_put(child);
255
+
256
+
break;
257
+
}
258
+
259
+
if (led->reg > U8_MAX) {
260
+
dev_err(priv->dev, "LED value %d is invalid", led->reg);
261
+
fwnode_handle_put(child);
262
+
263
+
return -EINVAL;
264
+
}
265
+
266
+
fwnode_property_read_string(child, "linux,default-trigger",
267
+
&led->ldev.default_trigger);
268
+
269
+
led->priv = priv;
270
+
led->ldev.max_brightness = LED_ON;
271
+
led->ldev.brightness_set_blocking = el15203000_set_blocking;
272
+
273
+
if (led->reg == 'S') {
274
+
led->ldev.pattern_set = el15203000_pattern_set_S;
275
+
led->ldev.pattern_clear = el15203000_pattern_clear;
276
+
} else if (led->reg == 'P') {
277
+
led->ldev.pattern_set = el15203000_pattern_set_P;
278
+
led->ldev.pattern_clear = el15203000_pattern_clear;
279
+
}
280
+
281
+
init_data.fwnode = child;
282
+
ret = devm_led_classdev_register_ext(priv->dev, &led->ldev,
283
+
&init_data);
284
+
if (ret) {
285
+
dev_err(priv->dev,
286
+
"failed to register LED device %s, err %d",
287
+
led->ldev.name, ret);
288
+
fwnode_handle_put(child);
289
+
290
+
break;
291
+
}
292
+
293
+
led++;
294
+
}
295
+
296
+
return ret;
297
+
}
298
+
299
+
static int el15203000_probe(struct spi_device *spi)
300
+
{
301
+
struct el15203000 *priv;
302
+
size_t count;
303
+
304
+
count = device_get_child_node_count(&spi->dev);
305
+
if (!count) {
306
+
dev_err(&spi->dev, "LEDs are not defined in device tree!");
307
+
return -ENODEV;
308
+
}
309
+
310
+
priv = devm_kzalloc(&spi->dev, struct_size(priv, leds, count),
311
+
GFP_KERNEL);
312
+
if (!priv)
313
+
return -ENOMEM;
314
+
315
+
mutex_init(&priv->lock);
316
+
priv->count = count;
317
+
priv->dev = &spi->dev;
318
+
priv->spi = spi;
319
+
priv->delay = jiffies -
320
+
usecs_to_jiffies(EL_FW_DELAY_USEC);
321
+
322
+
spi_set_drvdata(spi, priv);
323
+
324
+
return el15203000_probe_dt(priv);
325
+
}
326
+
327
+
static int el15203000_remove(struct spi_device *spi)
328
+
{
329
+
struct el15203000 *priv = spi_get_drvdata(spi);
330
+
331
+
mutex_destroy(&priv->lock);
332
+
333
+
return 0;
334
+
}
335
+
336
+
static const struct of_device_id el15203000_dt_ids[] = {
337
+
{ .compatible = "crane,el15203000", },
338
+
{},
339
+
};
340
+
341
+
MODULE_DEVICE_TABLE(of, el15203000_dt_ids);
342
+
343
+
static struct spi_driver el15203000_driver = {
344
+
.probe = el15203000_probe,
345
+
.remove = el15203000_remove,
346
+
.driver = {
347
+
.name = KBUILD_MODNAME,
348
+
.of_match_table = el15203000_dt_ids,
349
+
},
350
+
};
351
+
352
+
module_spi_driver(el15203000_driver);
353
+
354
+
MODULE_AUTHOR("Oleh Kravchenko <oleg@kaa.org.ua>");
355
+
MODULE_DESCRIPTION("el15203000 LED driver");
356
+
MODULE_LICENSE("GPL v2");
357
+
MODULE_ALIAS("spi:el15203000");