diff options
Diffstat (limited to 'driver/led/mp3385.c')
| -rw-r--r-- | driver/led/mp3385.c | 132 |
1 files changed, 132 insertions, 0 deletions
diff --git a/driver/led/mp3385.c b/driver/led/mp3385.c new file mode 100644 index 0000000000..278e333ae1 --- /dev/null +++ b/driver/led/mp3385.c @@ -0,0 +1,132 @@ +/* Copyright 2021 The Chromium OS Authors. All rights reserved. + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + * + * MPS MP3385 LED driver. + */ + +#include "console.h" +#include "gpio.h" +#include "hooks.h" +#include "i2c.h" +#include "mp3385.h" +#include "task.h" +#include "timer.h" + +#define CPRINTS(format, args...) cprints(CC_I2C, format, ## args) +#define CPRINTF(format, args...) cprintf(CC_I2C, format, ## args) + +#define I2C_ADDR_MP3385_FLAGS 0x31 + +struct mp3385_value { + uint8_t offset; + uint8_t data; +}; + +/* + * MP3385 asserts the interrupt when it's ready for writing settings, which + * are cleared when it's turned off. We enable the interrupt on HOOK_INIT and + * keep it enabled in S0/S3/S5. + * + * It's assumed the device doesn't have a lid and MP3385 is powered only in + * S0. For clamshell devices, different interrupt & power control scheme may be + * needed. + */ + +/* This ordering is suggested by vendor. */ +static struct mp3385_value mp3385_conf[] = { + /* + * Register 0x01: Operation frequency control + * Frequency selection: 300(KHz) + * Short circuit protection: 8(V) + */ + {.offset = 1, .data = 0x43}, + /* + * Register 0x02: LED current Full-Scale Register + * ISET Resistor: 127(Kohm) + * Maximum LED current: 20196/127 = 159(mA) + * Setting LED current: 62(mA) + */ + {.offset = 2, .data = 0x65}, + + /* Register 0x03: RO - ignored */ + + /* + * Register 0x04: Internal LED Dimming Brightness Register + * SMBus PWM function: None Use + */ + {.offset = 4, .data = 0x00}, + /* + * Register 0x05: OVP, OCP Threshold Register + * Over Current Protection: 0.5(V) + * Panel LED Voltage(Max): 47.8(V) + * OVP setting: 54(V) + */ + {.offset = 5, .data = 0x97}, + /* + * Register 0x00: Dimming mode Register + * String Selection: 4(Number) + * Interface Selection: 1 + * Brightness mode: 3 + */ + {.offset = 0, .data = 0xF2}, +}; +static const int mp3385_conf_size = ARRAY_SIZE(mp3385_conf); + +static void set_mp3385_reg(void) +{ + int i; + + for (i = 0; i < mp3385_conf_size; ++i) { + int rv = i2c_write8(I2C_PORT_BACKLIGHT, + I2C_ADDR_MP3385_FLAGS, + mp3385_conf[i].offset, mp3385_conf[i].data); + if (rv) { + CPRINTS("Write MP3385 register %d " + "failed rv=%d", i, rv); + return; + } + } + CPRINTS("Wrote MP3385 settings"); +} + +static void mp3385_backlight_enable_deferred(void) +{ + if (gpio_get_level(GPIO_PANEL_BACKLIGHT_EN)) + set_mp3385_reg(); +} +DECLARE_DEFERRED(mp3385_backlight_enable_deferred); + +void mp3385_interrupt(enum gpio_signal signal) +{ + /* + * 1. Spec says backlight should be turned on after 500ms + * after eDP signals are ready. + * + * 2. There's no way to get exact eDP ready time, therefore, + * give one second delay. + * + * power up __/---------------- + * eDP ______/------------ + * backlight _____________/----- + * |- t1 -| : >=500 ms + * |- t2 -| : 1 second is enough + */ + hook_call_deferred(&mp3385_backlight_enable_deferred_data, + MP3385_POWER_BACKLIGHT_DELAY); +} + +int mp3385_set_config(int offset, int data) +{ + int i; + + for (i = 0; i < mp3385_conf_size; i++) { + if (mp3385_conf[i].offset == offset) { + mp3385_conf[i].data = data; + return EC_SUCCESS; + } + } + + CPRINTS("mp3385: offset %d not found", i); + return EC_ERROR_INVAL; +} |