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Diffstat (limited to 'common/lb_common.c')
| -rw-r--r-- | common/lb_common.c | 345 |
1 files changed, 0 insertions, 345 deletions
diff --git a/common/lb_common.c b/common/lb_common.c deleted file mode 100644 index 019e0e254f..0000000000 --- a/common/lb_common.c +++ /dev/null @@ -1,345 +0,0 @@ -/* Copyright 2012 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. - * - * Lightbar IC interface - * - * Here's the API provided by this file. - * - * Looking at it from the outside, the lightbar has four "segments", each of - * which can be independently adjusted to display a unique color such as blue, - * purple, yellow, pinkish-white, etc. Segment 0 is on the left (looking - * straight at it from behind). - * - * The lb_set_rgb() and lb_get_rgb() functions let you specify the color of a - * segment using individual Red, Green, and Blue values in the 0x00 to 0xFF - * range (see https://en.wikipedia.org/wiki/Web_color for background info). - * - * The lb_set_brightness() function provides a simple way to set the intensity, - * over a range of 0x00 (off) to 0xFF (full brightness). It does this by - * scaling each RGB value proportionally. For example, an RGB value of #FF8000 - * appears orange. To make the segment half as bright, you could specify a RGB - * value of #7f4000, or you could leave the RGB value unchanged and just set - * the brightness to 0x80. - * - * That covers most of the lb_* functions found in include/lb_common.h, and - * those functions are what are used to implement the various colors and - * sequences for displaying power state changes and other events. - * - * The internals are a little more messy. - * - * Each segment has three individual color emitters - red, green, and blue. A - * single emitter may consist of 3 to 7 physical LEDs, but they are all wired - * in parallel so there is only one wire that provides current for any one - * color emitter. That makes a total of 12 current control wires for the - * lightbar: four segments, three color emitters per segment. - * - * The ICs that we use each have seven independently adjustable - * current-limiters. We use six of those current limiters (called "Independent - * Sink Controls", or "ISC"s ) from each of two ICs to control the 12 color - * emitters in the lightbar. The ICs are not identical, but they're close - * enough that we can treat them the same. We call the ICs "controller 0" and - * "controller 1". - * - * For no apparent reason, each Chromebook has wired the ICs and the ISCs - * differently, so there are a couple of lookup tables that ensure that when we - * call lb_set_rgb() to make segment 1 yellow, it looks the same on all - * Chromebooks. - * - * Each ISC has a control register to set the amount of current that passes - * through the color emitter control wire. We need to limit the max current so - * that the current through each of the emitter's LEDs doesn't exceed the - * manufacturer's specifications. For example, if a particular LED can't handle - * more than 5 mA, and the emitter is made up of four LEDs in parallel, the - * maxiumum limit for that particular ISC would be 20 mA. - * - * Although the specified maximum currents are usually similar, the three - * different colors of LEDs have different brightnesses. For any given current, - * green LEDs are pretty bright, red LEDS are medium, and blue are fairly dim. - * So we calibrate the max current per ISC differently, depending on which - * color it controls. - * - * First we set one segment to red, one to green, and one to blue, using the - * ISC register to allow the max current per LED that the LED manufacturer - * recommends. Then we adjust the current of the brighter segments downward - * until all three segments appear equally bright to the eye. The MAX_RED, - * MAX_BLUE, and MAX_GREEN values are the ISC control register values at this - * point. This means that if we set all ISCs to their MAX_* values, all - * segments should appear white. - * - * To translate the RGB values passed to lb_set_rgb() into ISC values, we - * perform two transformations. The color value is first scaled according to - * the current brightness setting, and then that intensity is scaled according - * to the MAX_* value for the particular color. The result is the ISC register - * value to use. - * - * To add lightbar support for a new Chromebook, you do the following: - * - * 1. Figure out the segment-to-IC and color-to-ISC mappings so that - * lb_set_rgb() does the same thing as on the other Chromebooks. - * - * 2. Calibrate the MAX_RED, MAX_GREEN, and MAX_BLUE values so that white looks - * white, and solid red, green, and blue all appear to be the same - * brightness. - * - * 3. Use lb_set_rgb() to set the colors to what *should be* the Google colors - * (at maximum brightness). Tweak the RGB values until the colors match, - * then edit common/lightbar.c to set them as the defaults. - * - * 4. Curse because the physical variation between the LEDs prevents you from - * getting everything exactly right: white looks bluish, yellow turns - * orange at lower brightness, segment 3 has a bright spot when displaying - * solid red, etc. Go back to step 2, and repeat until deadline. - */ - -#include "common.h" -#include "console.h" -#include "ec_commands.h" -#include "i2c.h" -#include "lb_common.h" -#include "util.h" - -/* Console output macros */ -#define CPUTS(outstr) cputs(CC_LIGHTBAR, outstr) -#define CPRINTF(format, args...) cprintf(CC_LIGHTBAR, format, ## args) -#define CPRINTS(format, args...) cprints(CC_LIGHTBAR, format, ## args) - -/******************************************************************************/ -/* How to talk to the controller */ -/******************************************************************************/ - -/* Since there's absolutely nothing we can do about it if an I2C access - * isn't working, we're completely ignoring any failures. */ - -static const uint16_t i2c_addr_flags[] = { 0x2A, 0x2B }; - -static inline void controller_write(int ctrl_num, uint8_t reg, uint8_t val) -{ - uint8_t buf[2]; - - buf[0] = reg; - buf[1] = val; - ctrl_num = ctrl_num % ARRAY_SIZE(i2c_addr_flags); - i2c_xfer_unlocked(I2C_PORT_LIGHTBAR, i2c_addr_flags[ctrl_num], - buf, 2, 0, 0, - I2C_XFER_SINGLE); -} - -static inline uint8_t controller_read(int ctrl_num, uint8_t reg) -{ - uint8_t buf[1]; - int rv; - - ctrl_num = ctrl_num % ARRAY_SIZE(i2c_addr_flags); - rv = i2c_xfer_unlocked(I2C_PORT_LIGHTBAR, i2c_addr_flags[ctrl_num], - ®, 1, buf, 1, I2C_XFER_SINGLE); - return rv ? 0 : buf[0]; -} - -/******************************************************************************/ -/* Controller details. We have an ADP8861 and and ADP8863, but we can treat - * them identically for our purposes */ -/******************************************************************************/ - -#ifdef BOARD_BDS -/* We need to limit the total current per ISC to no more than 20mA (5mA per - * color LED, but we have four LEDs in parallel on each ISC). Any more than - * that runs the risk of damaging the LED component. A value of 0x67 is as high - * as we want (assuming Square Law), but the blue LED is the least bright, so - * I've lowered the other colors until they all appear approximately equal - * brightness when full on. That's still pretty bright and a lot of current - * drain on the battery, so we'll probably rarely go that high. */ -#define MAX_RED 0x5c -#define MAX_GREEN 0x30 -#define MAX_BLUE 0x67 -#endif -#ifdef BOARD_HOST -/* For testing only */ -#define MAX_RED 0xff -#define MAX_GREEN 0xff -#define MAX_BLUE 0xff -#endif - -/* How we'd like to see the driver chips initialized. The controllers have some - * auto-cycling capability, but it's not much use for our purposes. For now, - * we'll just control all color changes actively. */ -struct initdata_s { - uint8_t reg; - uint8_t val; -}; - -static const struct initdata_s init_vals[] = { - {0x04, 0x00}, /* no backlight function */ - {0x05, 0x3f}, /* xRGBRGB per chip */ - {0x0f, 0x01}, /* square law looks better */ - {0x10, 0x3f}, /* enable independent LEDs */ - {0x11, 0x00}, /* no auto cycling */ - {0x12, 0x00}, /* no auto cycling */ - {0x13, 0x00}, /* instant fade in/out */ - {0x14, 0x00}, /* not using LED 7 */ - {0x15, 0x00}, /* current for LED 6 (blue) */ - {0x16, 0x00}, /* current for LED 5 (red) */ - {0x17, 0x00}, /* current for LED 4 (green) */ - {0x18, 0x00}, /* current for LED 3 (blue) */ - {0x19, 0x00}, /* current for LED 2 (red) */ - {0x1a, 0x00}, /* current for LED 1 (green) */ -}; - -/* Controller register lookup tables. */ -static const uint8_t led_to_ctrl[] = { 1, 1, 0, 0 }; -#ifdef BOARD_BDS -static const uint8_t led_to_isc[] = { 0x18, 0x15, 0x18, 0x15 }; -#endif -#ifdef BOARD_HOST -/* For testing only */ -static const uint8_t led_to_isc[] = { 0x15, 0x18, 0x15, 0x18 }; -#endif - -/* Scale 0-255 into max value */ -static inline uint8_t scale_abs(int val, int max) -{ - return (val * max)/255; -} - -/* This is the overall brightness control. */ -static int brightness = 0xc0; - -/* So that we can make brightness changes happen instantly, we need to track - * the current values. The values in the controllers aren't very helpful. */ -static uint8_t current[NUM_LEDS][3]; - -/* Scale 0-255 by brightness */ -static inline uint8_t scale(int val, int max) -{ - return scale_abs((val * brightness)/255, max); -} - -/* Helper function to set one LED color and remember it for later */ -static void setrgb(int led, int red, int green, int blue) -{ - int ctrl, bank; - current[led][0] = red; - current[led][1] = green; - current[led][2] = blue; - ctrl = led_to_ctrl[led]; - bank = led_to_isc[led]; - i2c_lock(I2C_PORT_LIGHTBAR, 1); - controller_write(ctrl, bank, scale(blue, MAX_BLUE)); - controller_write(ctrl, bank+1, scale(red, MAX_RED)); - controller_write(ctrl, bank+2, scale(green, MAX_GREEN)); - i2c_lock(I2C_PORT_LIGHTBAR, 0); -} - -/* LEDs are numbered 0-3, RGB values should be in 0-255. - * If you specify too large an LED, it sets them all. */ -void lb_set_rgb(unsigned int led, int red, int green, int blue) -{ - int i; - if (led >= NUM_LEDS) - for (i = 0; i < NUM_LEDS; i++) - setrgb(i, red, green, blue); - else - setrgb(led, red, green, blue); -} - -/* Get current LED values, if the LED number is in range. */ -int lb_get_rgb(unsigned int led, uint8_t *red, uint8_t *green, uint8_t *blue) -{ - if (led < 0 || led >= NUM_LEDS) - return EC_RES_INVALID_PARAM; - - *red = current[led][0]; - *green = current[led][1]; - *blue = current[led][2]; - - return EC_RES_SUCCESS; -} - -/* Change current display brightness (0-255) */ -void lb_set_brightness(unsigned int newval) -{ - int i; - CPRINTS("LB_bright 0x%02x", newval); - brightness = newval; - for (i = 0; i < NUM_LEDS; i++) - setrgb(i, current[i][0], current[i][1], current[i][2]); -} - -/* Get current display brightness (0-255) */ -uint8_t lb_get_brightness(void) -{ - return brightness; -} - -/* Initialize the controller ICs after reset */ -void lb_init(int use_lock) -{ - int i; - - CPRINTF("[%pT LB_init_vals ", PRINTF_TIMESTAMP_NOW); - for (i = 0; i < ARRAY_SIZE(init_vals); i++) { - CPRINTF("%c", '0' + i % 10); - if (use_lock) - i2c_lock(I2C_PORT_LIGHTBAR, 1); - controller_write(0, init_vals[i].reg, init_vals[i].val); - controller_write(1, init_vals[i].reg, init_vals[i].val); - if (use_lock) - i2c_lock(I2C_PORT_LIGHTBAR, 0); - } - CPRINTF("]\n"); - memset(current, 0, sizeof(current)); -} - -/* Just go into standby mode. No register values should change. */ -void lb_off(void) -{ - CPRINTS("LB_off"); - i2c_lock(I2C_PORT_LIGHTBAR, 1); - controller_write(0, 0x01, 0x00); - controller_write(1, 0x01, 0x00); - i2c_lock(I2C_PORT_LIGHTBAR, 0); -} - -/* Come out of standby mode. */ -void lb_on(void) -{ - CPRINTS("LB_on"); - i2c_lock(I2C_PORT_LIGHTBAR, 1); - controller_write(0, 0x01, 0x20); - controller_write(1, 0x01, 0x20); - i2c_lock(I2C_PORT_LIGHTBAR, 0); -} - -static const uint8_t dump_reglist[] = { - 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, - 0x08, 0x09, 0x0a, 0x0f, - 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, - 0x18, 0x19, 0x1a -}; - -/* Helper for host command to dump controller registers */ -void lb_hc_cmd_dump(struct ec_response_lightbar *out) -{ - int i; - uint8_t reg; - - BUILD_ASSERT(ARRAY_SIZE(dump_reglist) == - ARRAY_SIZE(out->dump.vals)); - - for (i = 0; i < ARRAY_SIZE(dump_reglist); i++) { - reg = dump_reglist[i]; - out->dump.vals[i].reg = reg; - i2c_lock(I2C_PORT_LIGHTBAR, 1); - out->dump.vals[i].ic0 = controller_read(0, reg); - out->dump.vals[i].ic1 = controller_read(1, reg); - i2c_lock(I2C_PORT_LIGHTBAR, 0); - } -} - -/* Helper for host command to write controller registers directly */ -void lb_hc_cmd_reg(const struct ec_params_lightbar *in) -{ - i2c_lock(I2C_PORT_LIGHTBAR, 1); - controller_write(in->reg.ctrl, in->reg.reg, in->reg.value); - i2c_lock(I2C_PORT_LIGHTBAR, 0); -} |