1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * h3xxx atmel micro companion support, notification LED subdevice
5  *
6  * Author : Linus Walleij <linus.walleij@linaro.org>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <linux/mfd/ipaq-micro.h>
12 #include <linux/leds.h>
13 
14 #define LED_YELLOW	0x00
15 #define LED_GREEN	0x01
16 
17 #define LED_EN       (1 << 4) /* LED ON/OFF 0:off, 1:on                       */
18 #define LED_AUTOSTOP (1 << 5) /* LED ON/OFF auto stop set 0:disable, 1:enable */
19 #define LED_ALWAYS   (1 << 6) /* LED Interrupt Mask 0:No mask, 1:mask         */
20 
micro_leds_brightness_set(struct led_classdev * led_cdev,enum led_brightness value)21 static int micro_leds_brightness_set(struct led_classdev *led_cdev,
22 				      enum led_brightness value)
23 {
24 	struct ipaq_micro *micro = dev_get_drvdata(led_cdev->dev->parent->parent);
25 	/*
26 	 * In this message:
27 	 * Byte 0 = LED color: 0 = yellow, 1 = green
28 	 *          yellow LED is always ~30 blinks per minute
29 	 * Byte 1 = duration (flags?) appears to be ignored
30 	 * Byte 2 = green ontime in 1/10 sec (deciseconds)
31 	 *          1 = 1/10 second
32 	 *          0 = 256/10 second
33 	 * Byte 3 = green offtime in 1/10 sec (deciseconds)
34 	 *          1 = 1/10 second
35 	 *          0 = 256/10 seconds
36 	 */
37 	struct ipaq_micro_msg msg = {
38 		.id = MSG_NOTIFY_LED,
39 		.tx_len = 4,
40 	};
41 
42 	msg.tx_data[0] = LED_GREEN;
43 	msg.tx_data[1] = 0;
44 	if (value) {
45 		msg.tx_data[2] = 0; /* Duty cycle 256 */
46 		msg.tx_data[3] = 1;
47 	} else {
48 		msg.tx_data[2] = 1;
49 		msg.tx_data[3] = 0; /* Duty cycle 256 */
50 	}
51 	return ipaq_micro_tx_msg_sync(micro, &msg);
52 }
53 
54 /* Maximum duty cycle in ms 256/10 sec = 25600 ms */
55 #define IPAQ_LED_MAX_DUTY 25600
56 
micro_leds_blink_set(struct led_classdev * led_cdev,unsigned long * delay_on,unsigned long * delay_off)57 static int micro_leds_blink_set(struct led_classdev *led_cdev,
58 				unsigned long *delay_on,
59 				unsigned long *delay_off)
60 {
61 	struct ipaq_micro *micro = dev_get_drvdata(led_cdev->dev->parent->parent);
62 	/*
63 	 * In this message:
64 	 * Byte 0 = LED color: 0 = yellow, 1 = green
65 	 *          yellow LED is always ~30 blinks per minute
66 	 * Byte 1 = duration (flags?) appears to be ignored
67 	 * Byte 2 = green ontime in 1/10 sec (deciseconds)
68 	 *          1 = 1/10 second
69 	 *          0 = 256/10 second
70 	 * Byte 3 = green offtime in 1/10 sec (deciseconds)
71 	 *          1 = 1/10 second
72 	 *          0 = 256/10 seconds
73 	 */
74 	struct ipaq_micro_msg msg = {
75 		.id = MSG_NOTIFY_LED,
76 		.tx_len = 4,
77 	};
78 
79 	msg.tx_data[0] = LED_GREEN;
80 	if (*delay_on > IPAQ_LED_MAX_DUTY ||
81 	    *delay_off > IPAQ_LED_MAX_DUTY)
82 		return -EINVAL;
83 
84 	if (*delay_on == 0 && *delay_off == 0) {
85 		*delay_on = 100;
86 		*delay_off = 100;
87 	}
88 
89 	msg.tx_data[1] = 0;
90 	if (*delay_on >= IPAQ_LED_MAX_DUTY)
91 		msg.tx_data[2] = 0;
92 	else
93 		msg.tx_data[2] = (u8) DIV_ROUND_CLOSEST(*delay_on, 100);
94 	if (*delay_off >= IPAQ_LED_MAX_DUTY)
95 		msg.tx_data[3] = 0;
96 	else
97 		msg.tx_data[3] = (u8) DIV_ROUND_CLOSEST(*delay_off, 100);
98 	return ipaq_micro_tx_msg_sync(micro, &msg);
99 }
100 
101 static struct led_classdev micro_led = {
102 	.name			= "led-ipaq-micro",
103 	.brightness_set_blocking = micro_leds_brightness_set,
104 	.blink_set		= micro_leds_blink_set,
105 	.flags			= LED_CORE_SUSPENDRESUME,
106 };
107 
micro_leds_probe(struct platform_device * pdev)108 static int micro_leds_probe(struct platform_device *pdev)
109 {
110 	int ret;
111 
112 	ret = devm_led_classdev_register(&pdev->dev, &micro_led);
113 	if (ret) {
114 		dev_err(&pdev->dev, "registering led failed: %d\n", ret);
115 		return ret;
116 	}
117 	dev_info(&pdev->dev, "iPAQ micro notification LED driver\n");
118 
119 	return 0;
120 }
121 
122 static struct platform_driver micro_leds_device_driver = {
123 	.driver = {
124 		.name    = "ipaq-micro-leds",
125 	},
126 	.probe   = micro_leds_probe,
127 };
128 module_platform_driver(micro_leds_device_driver);
129 
130 MODULE_LICENSE("GPL");
131 MODULE_DESCRIPTION("driver for iPAQ Atmel micro leds");
132 MODULE_ALIAS("platform:ipaq-micro-leds");
133