LXR uboot/drivers/misc/pca9551

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Copyright (C) 2015 Stefan Roese <sr@denx.de>
   4 */
   5
   6#include <common.h>
   7#include <errno.h>
   8#include <i2c.h>
   9
  10#ifndef CONFIG_PCA9551_I2C_ADDR
  11#error "CONFIG_PCA9551_I2C_ADDR not defined!"
  12#endif
  13
  14#define PCA9551_REG_INPUT       0x00    /* Input register (read only) */
  15#define PCA9551_REG_PSC0        0x01    /* Frequency prescaler 0 */
  16#define PCA9551_REG_PWM0        0x02    /* PWM0 */
  17#define PCA9551_REG_PSC1        0x03    /* Frequency prescaler 1 */
  18#define PCA9551_REG_PWM1        0x04    /* PWM1 */
  19#define PCA9551_REG_LS0         0x05    /* LED0 to LED3 selector */
  20#define PCA9551_REG_LS1         0x06    /* LED4 to LED7 selector */
  21
  22#define PCA9551_CTRL_AI         (1 << 4)        /* Auto-increment flag */
  23
  24#define PCA9551_LED_STATE_ON            0x00
  25#define PCA9551_LED_STATE_OFF           0x01
  26#define PCA9551_LED_STATE_BLINK0        0x02
  27#define PCA9551_LED_STATE_BLINK1        0x03
  28
  29struct pca9551_blink_rate {
  30        u8 psc; /* Frequency preescaler, see PCA9551_7.pdf p. 6 */
  31        u8 pwm; /* Pulse width modulation, see PCA9551_7.pdf p. 6 */
  32};
  33
  34static int freq_last = -1;
  35static int mask_last = -1;
  36static int idx_last = -1;
  37static int mode_last;
  38
  39static int pca9551_led_get_state(int led, int *state)
  40{
  41        unsigned int reg;
  42        u8 shift, buf;
  43        int ret;
  44
  45        if (led < 0 || led > 7) {
  46                return -EINVAL;
  47        } else if (led < 4) {
  48                reg = PCA9551_REG_LS0;
  49                shift = led << 1;
  50        } else {
  51                reg = PCA9551_REG_LS1;
  52                shift = (led - 4) << 1;
  53        }
  54
  55        ret = i2c_read(CONFIG_PCA9551_I2C_ADDR, reg, 1, &buf, 1);
  56        if (ret)
  57                return ret;
  58
  59        *state = (buf >> shift) & 0x03;
  60        return 0;
  61}
  62
  63static int pca9551_led_set_state(int led, int state)
  64{
  65        unsigned int reg;
  66        u8 shift, buf, mask;
  67        int ret;
  68
  69        if (led < 0 || led > 7) {
  70                return -EINVAL;
  71        } else if (led < 4) {
  72                reg = PCA9551_REG_LS0;
  73                shift = led << 1;
  74        } else {
  75                reg = PCA9551_REG_LS1;
  76                shift = (led - 4) << 1;
  77        }
  78        mask = 0x03 << shift;
  79
  80        ret = i2c_read(CONFIG_PCA9551_I2C_ADDR, reg, 1, &buf, 1);
  81        if (ret)
  82                return ret;
  83
  84        buf = (buf & ~mask) | ((state & 0x03) << shift);
  85
  86        ret = i2c_write(CONFIG_PCA9551_I2C_ADDR, reg, 1, &buf, 1);
  87        if (ret)
  88                return ret;
  89
  90        return 0;
  91}
  92
  93static int pca9551_led_set_blink_rate(int idx, struct pca9551_blink_rate rate)
  94{
  95        unsigned int reg;
  96        int ret;
  97
  98        switch (idx) {
  99        case 0:
 100                reg = PCA9551_REG_PSC0;
 101                break;
 102        case 1:
 103                reg = PCA9551_REG_PSC1;
 104                break;
 105        default:
 106                return -EINVAL;
 107        }
 108        reg |= PCA9551_CTRL_AI;
 109
 110        ret = i2c_write(CONFIG_PCA9551_I2C_ADDR, reg, 1, (u8 *)&rate, 2);
 111        if (ret)
 112                return ret;
 113
 114        return 0;
 115}
 116
 117/*
 118 * Functions referenced by cmd_led.c or status_led.c
 119 */
 120void __led_init(led_id_t id, int state)
 121{
 122}
 123
 124void __led_set(led_id_t mask, int state)
 125{
 126        if (state == CONFIG_LED_STATUS_OFF)
 127                pca9551_led_set_state(mask, PCA9551_LED_STATE_OFF);
 128        else
 129                pca9551_led_set_state(mask, PCA9551_LED_STATE_ON);
 130}
 131
 132void __led_toggle(led_id_t mask)
 133{
 134        int state = 0;
 135
 136        pca9551_led_get_state(mask, &state);
 137        pca9551_led_set_state(mask, !state);
 138}
 139
 140void __led_blink(led_id_t mask, int freq)
 141{
 142        struct pca9551_blink_rate rate;
 143        int mode;
 144        int idx;
 145
 146        if ((freq == freq_last) || (mask == mask_last)) {
 147                idx = idx_last;
 148                mode = mode_last;
 149        } else {
 150                /* Toggle blink index */
 151                if (idx_last == 0) {
 152                        idx = 1;
 153                        mode = PCA9551_LED_STATE_BLINK1;
 154                } else {
 155                        idx = 0;
 156                        mode = PCA9551_LED_STATE_BLINK0;
 157                }
 158
 159                idx_last = idx;
 160                mode_last = mode;
 161        }
 162        freq_last = freq;
 163        mask_last = mask;
 164
 165        rate.psc = ((freq * 38) / 1000) - 1;
 166        rate.pwm = 128;         /* 50% duty cycle */
 167
 168        pca9551_led_set_blink_rate(idx, rate);
 169        pca9551_led_set_state(mask, mode);
 170}
 171