root/drivers/leds/leds-ipaq-micro.c

DEFINITIONS

1. micro_leds_brightness_set
2. micro_leds_blink_set
3. micro_leds_probe

   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 
  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 
  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 
 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");