xref: /linux/drivers/leds/leds-ipaq-micro.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License version 2 as
4  * published by the Free Software Foundation.
5  *
6  * h3xxx atmel micro companion support, notification LED subdevice
7  *
8  * Author : Linus Walleij <linus.walleij@linaro.org>
9  */
10 
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/mfd/ipaq-micro.h>
14 #include <linux/leds.h>
15 
16 #define LED_YELLOW	0x00
17 #define LED_GREEN	0x01
18 
19 #define LED_EN          (1 << 4)        /* LED ON/OFF 0:off, 1:on                       */
20 #define LED_AUTOSTOP    (1 << 5)        /* LED ON/OFF auto stop set 0:disable, 1:enable */
21 #define LED_ALWAYS      (1 << 6)        /* LED Interrupt Mask 0:No mask, 1:mask         */
22 
23 static void micro_leds_brightness_set(struct led_classdev *led_cdev,
24 				      enum led_brightness value)
25 {
26 	struct ipaq_micro *micro = dev_get_drvdata(led_cdev->dev->parent->parent);
27 	/*
28 	 * In this message:
29 	 * Byte 0 = LED color: 0 = yellow, 1 = green
30 	 *          yellow LED is always ~30 blinks per minute
31 	 * Byte 1 = duration (flags?) appears to be ignored
32 	 * Byte 2 = green ontime in 1/10 sec (deciseconds)
33 	 *          1 = 1/10 second
34 	 *          0 = 256/10 second
35 	 * Byte 3 = green offtime in 1/10 sec (deciseconds)
36 	 *          1 = 1/10 second
37 	 *          0 = 256/10 seconds
38 	 */
39 	struct ipaq_micro_msg msg = {
40 		.id = MSG_NOTIFY_LED,
41 		.tx_len = 4,
42 	};
43 
44 	msg.tx_data[0] = LED_GREEN;
45 	msg.tx_data[1] = 0;
46 	if (value) {
47 		msg.tx_data[2] = 0; /* Duty cycle 256 */
48 		msg.tx_data[3] = 1;
49 	} else {
50 		msg.tx_data[2] = 1;
51 		msg.tx_data[3] = 0; /* Duty cycle 256 */
52 	}
53 	ipaq_micro_tx_msg_sync(micro, &msg);
54 }
55 
56 /* Maximum duty cycle in ms 256/10 sec = 25600 ms */
57 #define IPAQ_LED_MAX_DUTY 25600
58 
59 static int micro_leds_blink_set(struct led_classdev *led_cdev,
60 				unsigned long *delay_on,
61 				unsigned long *delay_off)
62 {
63 	struct ipaq_micro *micro = dev_get_drvdata(led_cdev->dev->parent->parent);
64 	/*
65 	 * In this message:
66 	 * Byte 0 = LED color: 0 = yellow, 1 = green
67 	 *          yellow LED is always ~30 blinks per minute
68 	 * Byte 1 = duration (flags?) appears to be ignored
69 	 * Byte 2 = green ontime in 1/10 sec (deciseconds)
70 	 *          1 = 1/10 second
71 	 *          0 = 256/10 second
72 	 * Byte 3 = green offtime in 1/10 sec (deciseconds)
73 	 *          1 = 1/10 second
74 	 *          0 = 256/10 seconds
75 	 */
76 	struct ipaq_micro_msg msg = {
77 		.id = MSG_NOTIFY_LED,
78 		.tx_len = 4,
79 	};
80 
81 	msg.tx_data[0] = LED_GREEN;
82         if (*delay_on > IPAQ_LED_MAX_DUTY ||
83 	    *delay_off > IPAQ_LED_MAX_DUTY)
84                 return -EINVAL;
85 
86         if (*delay_on == 0 && *delay_off == 0) {
87                 *delay_on = 100;
88                 *delay_off = 100;
89         }
90 
91 	msg.tx_data[1] = 0;
92 	if (*delay_on >= IPAQ_LED_MAX_DUTY)
93 		msg.tx_data[2] = 0;
94 	else
95 		msg.tx_data[2] = (u8) DIV_ROUND_CLOSEST(*delay_on, 100);
96 	if (*delay_off >= IPAQ_LED_MAX_DUTY)
97 		msg.tx_data[3] = 0;
98 	else
99 		msg.tx_data[3] = (u8) DIV_ROUND_CLOSEST(*delay_off, 100);
100 	return ipaq_micro_tx_msg_sync(micro, &msg);
101 }
102 
103 static struct led_classdev micro_led = {
104 	.name			= "led-ipaq-micro",
105 	.brightness_set		= micro_leds_brightness_set,
106 	.blink_set		= micro_leds_blink_set,
107 	.flags			= LED_CORE_SUSPENDRESUME,
108 };
109 
110 static int micro_leds_probe(struct platform_device *pdev)
111 {
112 	int ret;
113 
114 	ret = led_classdev_register(&pdev->dev, &micro_led);
115 	if (ret) {
116 		dev_err(&pdev->dev, "registering led failed: %d\n", ret);
117 		return ret;
118 	}
119 	dev_info(&pdev->dev, "iPAQ micro notification LED driver\n");
120 
121 	return 0;
122 }
123 
124 static int micro_leds_remove(struct platform_device *pdev)
125 {
126 	led_classdev_unregister(&micro_led);
127 	return 0;
128 }
129 
130 static struct platform_driver micro_leds_device_driver = {
131 	.driver = {
132 		.name    = "ipaq-micro-leds",
133 	},
134 	.probe   = micro_leds_probe,
135 	.remove  = micro_leds_remove,
136 };
137 module_platform_driver(micro_leds_device_driver);
138 
139 MODULE_LICENSE("GPL");
140 MODULE_DESCRIPTION("driver for iPAQ Atmel micro leds");
141 MODULE_ALIAS("platform:ipaq-micro-leds");
142