linux-imx

// 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;