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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 | // SPDX-License-Identifier: GPL-2.0-only /* * Copyright (C) 2011 Paul Parsons <lost.distance@yahoo.com> */ #include <linux/kernel.h> #include <linux/platform_device.h> #include <linux/leds.h> #include <linux/slab.h> #include <linux/mfd/asic3.h> #include <linux/mfd/core.h> #include <linux/module.h> /* * The HTC ASIC3 LED GPIOs are inputs, not outputs. * Hence we turn the LEDs on/off via the TimeBase register. */ /* * When TimeBase is 4 the clock resolution is about 32Hz. * This driver supports hardware blinking with an on+off * period from 62ms (2 clocks) to 125s (4000 clocks). */ #define MS_TO_CLK(ms) DIV_ROUND_CLOSEST(((ms)*1024), 32000) #define CLK_TO_MS(clk) (((clk)*32000)/1024) #define MAX_CLK 4000 /* Fits into 12-bit Time registers */ #define MAX_MS CLK_TO_MS(MAX_CLK) static const unsigned int led_n_base[ASIC3_NUM_LEDS] = { [0] = ASIC3_LED_0_Base, [1] = ASIC3_LED_1_Base, [2] = ASIC3_LED_2_Base, }; static void brightness_set(struct led_classdev *cdev, enum led_brightness value) { struct platform_device *pdev = to_platform_device(cdev->dev->parent); const struct mfd_cell *cell = mfd_get_cell(pdev); struct asic3 *asic = dev_get_drvdata(pdev->dev.parent); u32 timebase; unsigned int base; timebase = (value == LED_OFF) ? 0 : (LED_EN|0x4); base = led_n_base[cell->id]; asic3_write_register(asic, (base + ASIC3_LED_PeriodTime), 32); asic3_write_register(asic, (base + ASIC3_LED_DutyTime), 32); asic3_write_register(asic, (base + ASIC3_LED_AutoStopCount), 0); asic3_write_register(asic, (base + ASIC3_LED_TimeBase), timebase); } static int blink_set(struct led_classdev *cdev, unsigned long *delay_on, unsigned long *delay_off) { struct platform_device *pdev = to_platform_device(cdev->dev->parent); const struct mfd_cell *cell = mfd_get_cell(pdev); struct asic3 *asic = dev_get_drvdata(pdev->dev.parent); u32 on; u32 off; unsigned int base; if (*delay_on > MAX_MS || *delay_off > MAX_MS) return -EINVAL; if (*delay_on == 0 && *delay_off == 0) { /* If both are zero then a sensible default should be chosen */ on = MS_TO_CLK(500); off = MS_TO_CLK(500); } else { on = MS_TO_CLK(*delay_on); off = MS_TO_CLK(*delay_off); if ((on + off) > MAX_CLK) return -EINVAL; } base = led_n_base[cell->id]; asic3_write_register(asic, (base + ASIC3_LED_PeriodTime), (on + off)); asic3_write_register(asic, (base + ASIC3_LED_DutyTime), on); asic3_write_register(asic, (base + ASIC3_LED_AutoStopCount), 0); asic3_write_register(asic, (base + ASIC3_LED_TimeBase), (LED_EN|0x4)); *delay_on = CLK_TO_MS(on); *delay_off = CLK_TO_MS(off); return 0; } static int asic3_led_probe(struct platform_device *pdev) { struct asic3_led *led = dev_get_platdata(&pdev->dev); int ret; ret = mfd_cell_enable(pdev); if (ret < 0) return ret; led->cdev = devm_kzalloc(&pdev->dev, sizeof(struct led_classdev), GFP_KERNEL); if (!led->cdev) { ret = -ENOMEM; goto out; } led->cdev->name = led->name; led->cdev->flags = LED_CORE_SUSPENDRESUME; led->cdev->brightness_set = brightness_set; led->cdev->blink_set = blink_set; led->cdev->default_trigger = led->default_trigger; ret = led_classdev_register(&pdev->dev, led->cdev); if (ret < 0) goto out; return 0; out: (void) mfd_cell_disable(pdev); return ret; } static int asic3_led_remove(struct platform_device *pdev) { struct asic3_led *led = dev_get_platdata(&pdev->dev); led_classdev_unregister(led->cdev); return mfd_cell_disable(pdev); } #ifdef CONFIG_PM_SLEEP static int asic3_led_suspend(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); const struct mfd_cell *cell = mfd_get_cell(pdev); int ret; ret = 0; if (cell->suspend) ret = (*cell->suspend)(pdev); return ret; } static int asic3_led_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); const struct mfd_cell *cell = mfd_get_cell(pdev); int ret; ret = 0; if (cell->resume) ret = (*cell->resume)(pdev); return ret; } #endif static SIMPLE_DEV_PM_OPS(asic3_led_pm_ops, asic3_led_suspend, asic3_led_resume); static struct platform_driver asic3_led_driver = { .probe = asic3_led_probe, .remove = asic3_led_remove, .driver = { .name = "leds-asic3", .pm = &asic3_led_pm_ops, }, }; module_platform_driver(asic3_led_driver); MODULE_AUTHOR("Paul Parsons <lost.distance@yahoo.com>"); MODULE_DESCRIPTION("HTC ASIC3 LED driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:leds-asic3"); |