diff options
author | Bjorn Andersson <bjorn.andersson@linaro.org> | 2022-03-03 13:43:00 -0800 |
---|---|---|
committer | Pavel Machek <pavel@ucw.cz> | 2022-05-04 09:17:31 +0200 |
commit | 24e2d05d1b68981f22c984c766fabc5a93c83dba (patch) | |
tree | fe4321f09ea811d9873054cc81818731aed81b83 /drivers/leds/rgb | |
parent | a8e53db46f19f67be6a26488aafb7d10c78e33bd (diff) |
leds: Add driver for Qualcomm LPG
The Light Pulse Generator (LPG) is a PWM-block found in a wide range of
PMICs from Qualcomm. These PMICs typically comes with 1-8 LPG instances,
with their output being routed to various other components, such as
current sinks or GPIOs.
Each LPG instance can operate on fixed parameters or based on a shared
lookup-table, altering the duty cycle over time. This provides the means
for hardware assisted transitions of LED brightness.
A typical use case for the fixed parameter mode is to drive a PWM
backlight control signal, the driver therefor allows each LPG instance
to be exposed to the kernel either through the LED framework or the PWM
framework.
A typical use case for the LED configuration is to drive RGB LEDs in
smartphones etc, for which the driver supports multiple channels to be
ganged up to a MULTICOLOR LED. In this configuration the pattern
generators will be synchronized, to allow for multi-color patterns.
The idea of modelling this as a LED driver ontop of a PWM driver was
considered, but setting the properties related to patterns does not fit
in the PWM API. Similarly the idea of just duplicating the lower bits in
a PWM and LED driver separately was considered, but this would not allow
the PWM channels and LEDs to be configured on a per-board basis. The
driver implements the more complex LED interface, and provides a PWM
interface on the side of that, in the same driver.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Tested-by: Luca Weiss <luca@z3ntu.xyz>
Reviewed-by: Marijn Suijten <marijn.suijten@somainline.org>
Tested-by: Marijn Suijten <marijn.suijten@somainline.org>
[On the Sony Xperia Nile Discovery, SDM630]
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Diffstat (limited to 'drivers/leds/rgb')
-rw-r--r-- | drivers/leds/rgb/Kconfig | 18 | ||||
-rw-r--r-- | drivers/leds/rgb/Makefile | 3 | ||||
-rw-r--r-- | drivers/leds/rgb/leds-qcom-lpg.c | 1405 |
3 files changed, 1426 insertions, 0 deletions
diff --git a/drivers/leds/rgb/Kconfig b/drivers/leds/rgb/Kconfig new file mode 100644 index 000000000000..5dd27ad80856 --- /dev/null +++ b/drivers/leds/rgb/Kconfig @@ -0,0 +1,18 @@ +# SPDX-License-Identifier: GPL-2.0 + +if LEDS_CLASS_MULTICOLOR + +config LEDS_QCOM_LPG + tristate "LED support for Qualcomm LPG" + depends on OF + depends on SPMI + help + This option enables support for the Light Pulse Generator found in a + wide variety of Qualcomm PMICs. The LPG consists of a number of PWM + channels and typically a shared pattern lookup table and a current + sink, intended to drive RGB LEDs. Each channel can either be used as + a LED, grouped to represent a RGB LED or exposed as PWM channels. + + If compiled as a module, the module will be named leds-qcom-lpg. + +endif # LEDS_CLASS_MULTICOLOR diff --git a/drivers/leds/rgb/Makefile b/drivers/leds/rgb/Makefile new file mode 100644 index 000000000000..83114f44c4ea --- /dev/null +++ b/drivers/leds/rgb/Makefile @@ -0,0 +1,3 @@ +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_LEDS_QCOM_LPG) += leds-qcom-lpg.o diff --git a/drivers/leds/rgb/leds-qcom-lpg.c b/drivers/leds/rgb/leds-qcom-lpg.c new file mode 100644 index 000000000000..17576f77c423 --- /dev/null +++ b/drivers/leds/rgb/leds-qcom-lpg.c @@ -0,0 +1,1405 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2017-2022 Linaro Ltd + * Copyright (c) 2010-2012, The Linux Foundation. All rights reserved. + */ +#include <linux/bits.h> +#include <linux/bitfield.h> +#include <linux/led-class-multicolor.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#define LPG_SUBTYPE_REG 0x05 +#define LPG_SUBTYPE_LPG 0x2 +#define LPG_SUBTYPE_PWM 0xb +#define LPG_SUBTYPE_LPG_LITE 0x11 +#define LPG_PATTERN_CONFIG_REG 0x40 +#define LPG_SIZE_CLK_REG 0x41 +#define PWM_CLK_SELECT_MASK GENMASK(1, 0) +#define LPG_PREDIV_CLK_REG 0x42 +#define PWM_FREQ_PRE_DIV_MASK GENMASK(6, 5) +#define PWM_FREQ_EXP_MASK GENMASK(2, 0) +#define PWM_TYPE_CONFIG_REG 0x43 +#define PWM_VALUE_REG 0x44 +#define PWM_ENABLE_CONTROL_REG 0x46 +#define PWM_SYNC_REG 0x47 +#define LPG_RAMP_DURATION_REG 0x50 +#define LPG_HI_PAUSE_REG 0x52 +#define LPG_LO_PAUSE_REG 0x54 +#define LPG_HI_IDX_REG 0x56 +#define LPG_LO_IDX_REG 0x57 +#define PWM_SEC_ACCESS_REG 0xd0 +#define PWM_DTEST_REG(x) (0xe2 + (x) - 1) + +#define TRI_LED_SRC_SEL 0x45 +#define TRI_LED_EN_CTL 0x46 +#define TRI_LED_ATC_CTL 0x47 + +#define LPG_LUT_REG(x) (0x40 + (x) * 2) +#define RAMP_CONTROL_REG 0xc8 + +#define LPG_RESOLUTION 512 +#define LPG_MAX_M 7 + +struct lpg_channel; +struct lpg_data; + +/** + * struct lpg - LPG device context + * @dev: pointer to LPG device + * @map: regmap for register access + * @lock: used to synchronize LED and pwm callback requests + * @pwm: PWM-chip object, if operating in PWM mode + * @data: reference to version specific data + * @lut_base: base address of the LUT block (optional) + * @lut_size: number of entries in the LUT block + * @lut_bitmap: allocation bitmap for LUT entries + * @triled_base: base address of the TRILED block (optional) + * @triled_src: power-source for the TRILED + * @triled_has_atc_ctl: true if there is TRI_LED_ATC_CTL register + * @triled_has_src_sel: true if there is TRI_LED_SRC_SEL register + * @channels: list of PWM channels + * @num_channels: number of @channels + */ +struct lpg { + struct device *dev; + struct regmap *map; + + struct mutex lock; + + struct pwm_chip pwm; + + const struct lpg_data *data; + + u32 lut_base; + u32 lut_size; + unsigned long *lut_bitmap; + + u32 triled_base; + u32 triled_src; + bool triled_has_atc_ctl; + bool triled_has_src_sel; + + struct lpg_channel *channels; + unsigned int num_channels; +}; + +/** + * struct lpg_channel - per channel data + * @lpg: reference to parent lpg + * @base: base address of the PWM channel + * @triled_mask: mask in TRILED to enable this channel + * @lut_mask: mask in LUT to start pattern generator for this channel + * @subtype: PMIC hardware block subtype + * @in_use: channel is exposed to LED framework + * @color: color of the LED attached to this channel + * @dtest_line: DTEST line for output, or 0 if disabled + * @dtest_value: DTEST line configuration + * @pwm_value: duty (in microseconds) of the generated pulses, overridden by LUT + * @enabled: output enabled? + * @period: period (in nanoseconds) of the generated pulses + * @clk_sel: reference clock frequency selector + * @pre_div_sel: divider selector of the reference clock + * @pre_div_exp: exponential divider of the reference clock + * @ramp_enabled: duty cycle is driven by iterating over lookup table + * @ramp_ping_pong: reverse through pattern, rather than wrapping to start + * @ramp_oneshot: perform only a single pass over the pattern + * @ramp_reverse: iterate over pattern backwards + * @ramp_tick_ms: length (in milliseconds) of one step in the pattern + * @ramp_lo_pause_ms: pause (in milliseconds) before iterating over pattern + * @ramp_hi_pause_ms: pause (in milliseconds) after iterating over pattern + * @pattern_lo_idx: start index of associated pattern + * @pattern_hi_idx: last index of associated pattern + */ +struct lpg_channel { + struct lpg *lpg; + + u32 base; + unsigned int triled_mask; + unsigned int lut_mask; + unsigned int subtype; + + bool in_use; + + int color; + + u32 dtest_line; + u32 dtest_value; + + u16 pwm_value; + bool enabled; + + u64 period; + unsigned int clk_sel; + unsigned int pre_div_sel; + unsigned int pre_div_exp; + + bool ramp_enabled; + bool ramp_ping_pong; + bool ramp_oneshot; + bool ramp_reverse; + unsigned short ramp_tick_ms; + unsigned long ramp_lo_pause_ms; + unsigned long ramp_hi_pause_ms; + + unsigned int pattern_lo_idx; + unsigned int pattern_hi_idx; +}; + +/** + * struct lpg_led - logical LED object + * @lpg: lpg context reference + * @cdev: LED class device + * @mcdev: Multicolor LED class device + * @num_channels: number of @channels + * @channels: list of channels associated with the LED + */ +struct lpg_led { + struct lpg *lpg; + + struct led_classdev cdev; + struct led_classdev_mc mcdev; + + unsigned int num_channels; + struct lpg_channel *channels[]; +}; + +/** + * struct lpg_channel_data - per channel initialization data + * @base: base address for PWM channel registers + * @triled_mask: bitmask for controlling this channel in TRILED + */ +struct lpg_channel_data { + unsigned int base; + u8 triled_mask; +}; + +/** + * struct lpg_data - initialization data + * @lut_base: base address of LUT block + * @lut_size: number of entries in LUT + * @triled_base: base address of TRILED + * @triled_has_atc_ctl: true if there is TRI_LED_ATC_CTL register + * @triled_has_src_sel: true if there is TRI_LED_SRC_SEL register + * @num_channels: number of channels in LPG + * @channels: list of channel initialization data + */ +struct lpg_data { + unsigned int lut_base; + unsigned int lut_size; + unsigned int triled_base; + bool triled_has_atc_ctl; + bool triled_has_src_sel; + int num_channels; + const struct lpg_channel_data *channels; +}; + +static int triled_set(struct lpg *lpg, unsigned int mask, unsigned int enable) +{ + /* Skip if we don't have a triled block */ + if (!lpg->triled_base) + return 0; + + return regmap_update_bits(lpg->map, lpg->triled_base + TRI_LED_EN_CTL, + mask, enable); +} + +static int lpg_lut_store(struct lpg *lpg, struct led_pattern *pattern, + size_t len, unsigned int *lo_idx, unsigned int *hi_idx) +{ + unsigned int idx; + u16 val; + int i; + + idx = bitmap_find_next_zero_area(lpg->lut_bitmap, lpg->lut_size, + 0, len, 0); + if (idx >= lpg->lut_size) + return -ENOMEM; + + for (i = 0; i < len; i++) { + val = pattern[i].brightness; + + regmap_bulk_write(lpg->map, lpg->lut_base + LPG_LUT_REG(idx + i), + &val, sizeof(val)); + } + + bitmap_set(lpg->lut_bitmap, idx, len); + + *lo_idx = idx; + *hi_idx = idx + len - 1; + + return 0; +} + +static void lpg_lut_free(struct lpg *lpg, unsigned int lo_idx, unsigned int hi_idx) +{ + int len; + + len = hi_idx - lo_idx + 1; + if (len == 1) + return; + + bitmap_clear(lpg->lut_bitmap, lo_idx, len); +} + +static int lpg_lut_sync(struct lpg *lpg, unsigned int mask) +{ + return regmap_write(lpg->map, lpg->lut_base + RAMP_CONTROL_REG, mask); +} + +static const unsigned int lpg_clk_rates[] = {0, 1024, 32768, 19200000}; +static const unsigned int lpg_pre_divs[] = {1, 3, 5, 6}; + +static int lpg_calc_freq(struct lpg_channel *chan, uint64_t period) +{ + unsigned int clk_sel, best_clk = 0; + unsigned int div, best_div = 0; + unsigned int m, best_m = 0; + unsigned int error; + unsigned int best_err = UINT_MAX; + u64 best_period = 0; + u64 max_period; + + /* + * The PWM period is determined by: + * + * resolution * pre_div * 2^M + * period = -------------------------- + * refclk + * + * With resolution fixed at 2^9 bits, pre_div = {1, 3, 5, 6} and + * M = [0..7]. + * + * This allows for periods between 27uS and 384s, as the PWM framework + * wants a period of equal or lower length than requested, reject + * anything below 27uS. + */ + if (period <= (u64)NSEC_PER_SEC * LPG_RESOLUTION / 19200000) + return -EINVAL; + + /* Limit period to largest possible value, to avoid overflows */ + max_period = (u64)NSEC_PER_SEC * LPG_RESOLUTION * 6 * (1 << LPG_MAX_M) / 1024; + if (period > max_period) + period = max_period; + + /* + * Search for the pre_div, refclk and M by solving the rewritten formula + * for each refclk and pre_div value: + * + * period * refclk + * M = log2 ------------------------------------- + * NSEC_PER_SEC * pre_div * resolution + */ + for (clk_sel = 1; clk_sel < ARRAY_SIZE(lpg_clk_rates); clk_sel++) { + u64 numerator = period * lpg_clk_rates[clk_sel]; + + for (div = 0; div < ARRAY_SIZE(lpg_pre_divs); div++) { + u64 denominator = (u64)NSEC_PER_SEC * lpg_pre_divs[div] * LPG_RESOLUTION; + u64 actual; + u64 ratio; + + if (numerator < denominator) + continue; + + ratio = div64_u64(numerator, denominator); + m = ilog2(ratio); + if (m > LPG_MAX_M) + m = LPG_MAX_M; + + actual = DIV_ROUND_UP_ULL(denominator * (1 << m), lpg_clk_rates[clk_sel]); + + error = period - actual; + if (error < best_err) { + best_err = error; + + best_div = div; + best_m = m; + best_clk = clk_sel; + best_period = actual; + } + } + } + + chan->clk_sel = best_clk; + chan->pre_div_sel = best_div; + chan->pre_div_exp = best_m; + chan->period = best_period; + + return 0; +} + +static void lpg_calc_duty(struct lpg_channel *chan, uint64_t duty) +{ + unsigned int max = LPG_RESOLUTION - 1; + unsigned int val; + + val = div64_u64(duty * lpg_clk_rates[chan->clk_sel], + (u64)NSEC_PER_SEC * lpg_pre_divs[chan->pre_div_sel] * (1 << chan->pre_div_exp)); + + chan->pwm_value = min(val, max); +} + +static void lpg_apply_freq(struct lpg_channel *chan) +{ + unsigned long val; + struct lpg *lpg = chan->lpg; + + if (!chan->enabled) + return; + + val = chan->clk_sel; + + /* Specify 9bit resolution, based on the subtype of the channel */ + switch (chan->subtype) { + case LPG_SUBTYPE_LPG: + val |= GENMASK(5, 4); + break; + case LPG_SUBTYPE_PWM: + val |= BIT(2); + break; + case LPG_SUBTYPE_LPG_LITE: + default: + val |= BIT(4); + break; + } + + regmap_write(lpg->map, chan->base + LPG_SIZE_CLK_REG, val); + + val = FIELD_PREP(PWM_FREQ_PRE_DIV_MASK, chan->pre_div_sel) | + FIELD_PREP(PWM_FREQ_EXP_MASK, chan->pre_div_exp); + regmap_write(lpg->map, chan->base + LPG_PREDIV_CLK_REG, val); +} + +#define LPG_ENABLE_GLITCH_REMOVAL BIT(5) + +static void lpg_enable_glitch(struct lpg_channel *chan) +{ + struct lpg *lpg = chan->lpg; + + regmap_update_bits(lpg->map, chan->base + PWM_TYPE_CONFIG_REG, + LPG_ENABLE_GLITCH_REMOVAL, 0); +} + +static void lpg_disable_glitch(struct lpg_channel *chan) +{ + struct lpg *lpg = chan->lpg; + + regmap_update_bits(lpg->map, chan->base + PWM_TYPE_CONFIG_REG, + LPG_ENABLE_GLITCH_REMOVAL, + LPG_ENABLE_GLITCH_REMOVAL); +} + +static void lpg_apply_pwm_value(struct lpg_channel *chan) +{ + struct lpg *lpg = chan->lpg; + u16 val = chan->pwm_value; + + if (!chan->enabled) + return; + + regmap_bulk_write(lpg->map, chan->base + PWM_VALUE_REG, &val, sizeof(val)); +} + +#define LPG_PATTERN_CONFIG_LO_TO_HI BIT(4) +#define LPG_PATTERN_CONFIG_REPEAT BIT(3) +#define LPG_PATTERN_CONFIG_TOGGLE BIT(2) +#define LPG_PATTERN_CONFIG_PAUSE_HI BIT(1) +#define LPG_PATTERN_CONFIG_PAUSE_LO BIT(0) + +static void lpg_apply_lut_control(struct lpg_channel *chan) +{ + struct lpg *lpg = chan->lpg; + unsigned int hi_pause; + unsigned int lo_pause; + unsigned int conf = 0; + unsigned int lo_idx = chan->pattern_lo_idx; + unsigned int hi_idx = chan->pattern_hi_idx; + u16 step = chan->ramp_tick_ms; + + if (!chan->ramp_enabled || chan->pattern_lo_idx == chan->pattern_hi_idx) + return; + + hi_pause = DIV_ROUND_UP(chan->ramp_hi_pause_ms, step); + lo_pause = DIV_ROUND_UP(chan->ramp_lo_pause_ms, step); + + if (!chan->ramp_reverse) + conf |= LPG_PATTERN_CONFIG_LO_TO_HI; + if (!chan->ramp_oneshot) + conf |= LPG_PATTERN_CONFIG_REPEAT; + if (chan->ramp_ping_pong) + conf |= LPG_PATTERN_CONFIG_TOGGLE; + if (chan->ramp_hi_pause_ms) + conf |= LPG_PATTERN_CONFIG_PAUSE_HI; + if (chan->ramp_lo_pause_ms) + conf |= LPG_PATTERN_CONFIG_PAUSE_LO; + + regmap_write(lpg->map, chan->base + LPG_PATTERN_CONFIG_REG, conf); + regmap_write(lpg->map, chan->base + LPG_HI_IDX_REG, hi_idx); + regmap_write(lpg->map, chan->base + LPG_LO_IDX_REG, lo_idx); + + regmap_bulk_write(lpg->map, chan->base + LPG_RAMP_DURATION_REG, &step, sizeof(step)); + regmap_write(lpg->map, chan->base + LPG_HI_PAUSE_REG, hi_pause); + regmap_write(lpg->map, chan->base + LPG_LO_PAUSE_REG, lo_pause); +} + +#define LPG_ENABLE_CONTROL_OUTPUT BIT(7) +#define LPG_ENABLE_CONTROL_BUFFER_TRISTATE BIT(5) +#define LPG_ENABLE_CONTROL_SRC_PWM BIT(2) +#define LPG_ENABLE_CONTROL_RAMP_GEN BIT(1) + +static void lpg_apply_control(struct lpg_channel *chan) +{ + unsigned int ctrl; + struct lpg *lpg = chan->lpg; + + ctrl = LPG_ENABLE_CONTROL_BUFFER_TRISTATE; + + if (chan->enabled) + ctrl |= LPG_ENABLE_CONTROL_OUTPUT; + + if (chan->pattern_lo_idx != chan->pattern_hi_idx) + ctrl |= LPG_ENABLE_CONTROL_RAMP_GEN; + else + ctrl |= LPG_ENABLE_CONTROL_SRC_PWM; + + regmap_write(lpg->map, chan->base + PWM_ENABLE_CONTROL_REG, ctrl); + + /* + * Due to LPG hardware bug, in the PWM mode, having enabled PWM, + * We have to write PWM values one more time. + */ + if (chan->enabled) + lpg_apply_pwm_value(chan); +} + +#define LPG_SYNC_PWM BIT(0) + +static void lpg_apply_sync(struct lpg_channel *chan) +{ + struct lpg *lpg = chan->lpg; + + regmap_write(lpg->map, chan->base + PWM_SYNC_REG, LPG_SYNC_PWM); +} + +static int lpg_parse_dtest(struct lpg *lpg) +{ + struct lpg_channel *chan; + struct device_node *np = lpg->dev->of_node; + int count; + int ret; + int i; + + count = of_property_count_u32_elems(np, "qcom,dtest"); + if (count == -EINVAL) { + return 0; + } else if (count < 0) { + ret = count; + goto err_malformed; + } else if (count != lpg->data->num_channels * 2) { + dev_err(lpg->dev, "qcom,dtest needs to be %d items\n", + lpg->data->num_channels * 2); + return -EINVAL; + } + + for (i = 0; i < lpg->data->num_channels; i++) { + chan = &lpg->channels[i]; + + ret = of_property_read_u32_index(np, "qcom,dtest", i * 2, + &chan->dtest_line); + if (ret) + goto err_malformed; + + ret = of_property_read_u32_index(np, "qcom,dtest", i * 2 + 1, + &chan->dtest_value); + if (ret) + goto err_malformed; + } + + return 0; + +err_malformed: + dev_err(lpg->dev, "malformed qcom,dtest\n"); + return ret; +} + +static void lpg_apply_dtest(struct lpg_channel *chan) +{ + struct lpg *lpg = chan->lpg; + + if (!chan->dtest_line) + return; + + regmap_write(lpg->map, chan->base + PWM_SEC_ACCESS_REG, 0xa5); + regmap_write(lpg->map, chan->base + PWM_DTEST_REG(chan->dtest_line), + chan->dtest_value); +} + +static void lpg_apply(struct lpg_channel *chan) +{ + lpg_disable_glitch(chan); + lpg_apply_freq(chan); + lpg_apply_pwm_value(chan); + lpg_apply_control(chan); + lpg_apply_sync(chan); + lpg_apply_lut_control(chan); + lpg_enable_glitch(chan); +} + +static void lpg_brightness_set(struct lpg_led *led, struct led_classdev *cdev, + struct mc_subled *subleds) +{ + enum led_brightness brightness; + struct lpg_channel *chan; + unsigned int triled_enabled = 0; + unsigned int triled_mask = 0; + unsigned int lut_mask = 0; + unsigned int duty; + struct lpg *lpg = led->lpg; + int i; + + for (i = 0; i < led->num_channels; i++) { + chan = led->channels[i]; + brightness = subleds[i].brightness; + + if (brightness == LED_OFF) { + chan->enabled = false; + chan->ramp_enabled = false; + } else if (chan->pattern_lo_idx != chan->pattern_hi_idx) { + lpg_calc_freq(chan, NSEC_PER_MSEC); + + chan->enabled = true; + chan->ramp_enabled = true; + + lut_mask |= chan->lut_mask; + triled_enabled |= chan->triled_mask; + } else { + lpg_calc_freq(chan, NSEC_PER_MSEC); + + duty = div_u64(brightness * chan->period, cdev->max_brightness); + lpg_calc_duty(chan, duty); + chan->enabled = true; + chan->ramp_enabled = false; + + triled_enabled |= chan->triled_mask; + } + + triled_mask |= chan->triled_mask; + + lpg_apply(chan); + } + + /* Toggle triled lines */ + if (triled_mask) + triled_set(lpg, triled_mask, triled_enabled); + + /* Trigger start of ramp generator(s) */ + if (lut_mask) + lpg_lut_sync(lpg, lut_mask); +} + +static void lpg_brightness_single_set(struct led_classdev *cdev, + enum led_brightness value) +{ + struct lpg_led *led = container_of(cdev, struct lpg_led, cdev); + struct mc_subled info; + + mutex_lock(&led->lpg->lock); + + info.brightness = value; + lpg_brightness_set(led, cdev, &info); + + mutex_unlock(&led->lpg->lock); +} + +static void lpg_brightness_mc_set(struct led_classdev *cdev, + enum led_brightness value) +{ + struct led_classdev_mc *mc = lcdev_to_mccdev(cdev); + struct lpg_led *led = container_of(mc, struct lpg_led, mcdev); + + mutex_lock(&led->lpg->lock); + + led_mc_calc_color_components(mc, value); + lpg_brightness_set(led, cdev, mc->subled_info); + + mutex_unlock(&led->lpg->lock); +} + +static int lpg_blink_set(struct lpg_led *led, + unsigned long *delay_on, unsigned long *delay_off) +{ + struct lpg_channel *chan; + unsigned int period; + unsigned int triled_mask = 0; + struct lpg *lpg = led->lpg; + u64 duty; + int i; + + if (!*delay_on && !*delay_off) { + *delay_on = 500; + *delay_off = 500; + } + + duty = *delay_on * NSEC_PER_MSEC; + period = (*delay_on + *delay_off) * NSEC_PER_MSEC; + + for (i = 0; i < led->num_channels; i++) { + chan = led->channels[i]; + + lpg_calc_freq(chan, period); + lpg_calc_duty(chan, duty); + + chan->enabled = true; + chan->ramp_enabled = false; + + triled_mask |= chan->triled_mask; + + lpg_apply(chan); + } + + /* Enable triled lines */ + triled_set(lpg, triled_mask, triled_mask); + + chan = led->channels[0]; + duty = div_u64(chan->pwm_value * chan->period, LPG_RESOLUTION); + *delay_on = div_u64(duty, NSEC_PER_MSEC); + *delay_off = div_u64(chan->period - duty, NSEC_PER_MSEC); + + return 0; +} + +static int lpg_blink_single_set(struct led_classdev *cdev, + unsigned long *delay_on, unsigned long *delay_off) +{ + struct lpg_led *led = container_of(cdev, struct lpg_led, cdev); + int ret; + + mutex_lock(&led->lpg->lock); + + ret = lpg_blink_set(led, delay_on, delay_off); + + mutex_unlock(&led->lpg->lock); + + return ret; +} + +static int lpg_blink_mc_set(struct led_classdev *cdev, + unsigned long *delay_on, unsigned long *delay_off) +{ + struct led_classdev_mc *mc = lcdev_to_mccdev(cdev); + struct lpg_led *led = container_of(mc, struct lpg_led, mcdev); + int ret; + + mutex_lock(&led->lpg->lock); + + ret = lpg_blink_set(led, delay_on, delay_off); + + mutex_unlock(&led->lpg->lock); + + return ret; +} + +static int lpg_pattern_set(struct lpg_led *led, struct led_pattern *pattern, + u32 len, int repeat) +{ + struct lpg_channel *chan; + struct lpg *lpg = led->lpg; + unsigned int brightness_a; + unsigned int brightness_b; + unsigned int actual_len; + unsigned int hi_pause; + unsigned int lo_pause; + unsigned int delta_t; + unsigned int lo_idx; + unsigned int hi_idx; + unsigned int i; + bool ping_pong = true; + int ret; + + /* Hardware only support oneshot or indefinite loops */ + if (repeat != -1 && repeat != 1) + return -EINVAL; + + /* + * Specifying a pattern of length 1 causes the hardware to iterate + * through the entire LUT, so prohibit this. + */ + if (len < 2) + return -EINVAL; + + /* + * The LPG plays patterns with at a fixed pace, a "low pause" can be + * used to stretch the first delay of the pattern and a "high pause" + * the last one. + * + * In order to save space the pattern can be played in "ping pong" + * mode, in which the pattern is first played forward, then "high + * pause" is applied, then the pattern is played backwards and finally + * the "low pause" is applied. + * + * The middle elements of the pattern are used to determine delta_t and + * the "low pause" and "high pause" multipliers are derrived from this. + * + * The first element in the pattern is used to determine "low pause". + * + * If the specified pattern is a palindrome the ping pong mode is + * enabled. In this scenario the delta_t of the middle entry (i.e. the + * last in the programmed pattern) determines the "high pause". + */ + + /* Detect palindromes and use "ping pong" to reduce LUT usage */ + for (i = 0; i < len / 2; i++) { + brightness_a = pattern[i].brightness; + brightness_b = pattern[len - i - 1].brightness; + + if (brightness_a != brightness_b) { + ping_pong = false; + break; + } + } + + /* The pattern length to be written to the LUT */ + if (ping_pong) + actual_len = (len + 1) / 2; + else + actual_len = len; + + /* + * Validate that all delta_t in the pattern are the same, with the + * exception of the middle element in case of ping_pong. + */ + delta_t = pattern[1].delta_t; + for (i = 2; i < len; i++) { + if (pattern[i].delta_t != delta_t) { + /* + * Allow last entry in the full or shortened pattern to + * specify hi pause. Reject other variations. + */ + if (i != actual_len - 1) + return -EINVAL; + } + } + + /* LPG_RAMP_DURATION_REG is a 9bit */ + if (delta_t >= BIT(9)) + return -EINVAL; + + /* Find "low pause" and "high pause" in the pattern */ + lo_pause = pattern[0].delta_t; + hi_pause = pattern[actual_len - 1].delta_t; + + mutex_lock(&lpg->lock); + ret = lpg_lut_store(lpg, pattern, actual_len, &lo_idx, &hi_idx); + if (ret < 0) + goto out_unlock; + + for (i = 0; i < led->num_channels; i++) { + chan = led->channels[i]; + + chan->ramp_tick_ms = delta_t; + chan->ramp_ping_pong = ping_pong; + chan->ramp_oneshot = repeat != -1; + + chan->ramp_lo_pause_ms = lo_pause; + chan->ramp_hi_pause_ms = hi_pause; + + chan->pattern_lo_idx = lo_idx; + chan->pattern_hi_idx = hi_idx; + } + +out_unlock: + mutex_unlock(&lpg->lock); + + return ret; +} + +static int lpg_pattern_single_set(struct led_classdev *cdev, + struct led_pattern *pattern, u32 len, + int repeat) +{ + struct lpg_led *led = container_of(cdev, struct lpg_led, cdev); + int ret; + + ret = lpg_pattern_set(led, pattern, len, repeat); + if (ret < 0) + return ret; + + lpg_brightness_single_set(cdev, LED_FULL); + + return 0; +} + +static int lpg_pattern_mc_set(struct led_classdev *cdev, + struct led_pattern *pattern, u32 len, + int repeat) +{ + struct led_classdev_mc *mc = lcdev_to_mccdev(cdev); + struct lpg_led *led = container_of(mc, struct lpg_led, mcdev); + int ret; + + ret = lpg_pattern_set(led, pattern, len, repeat); + if (ret < 0) + return ret; + + led_mc_calc_color_components(mc, LED_FULL); + lpg_brightness_set(led, cdev, mc->subled_info); + + return 0; +} + +static int lpg_pattern_clear(struct lpg_led *led) +{ + struct lpg_channel *chan; + struct lpg *lpg = led->lpg; + int i; + + mutex_lock(&lpg->lock); + + chan = led->channels[0]; + lpg_lut_free(lpg, chan->pattern_lo_idx, chan->pattern_hi_idx); + + for (i = 0; i < led->num_channels; i++) { + chan = led->channels[i]; + chan->pattern_lo_idx = 0; + chan->pattern_hi_idx = 0; + } + + mutex_unlock(&lpg->lock); + + return 0; +} + +static int lpg_pattern_single_clear(struct led_classdev *cdev) +{ + struct lpg_led *led = container_of(cdev, struct lpg_led, cdev); + + return lpg_pattern_clear(led); +} + +static int lpg_pattern_mc_clear(struct led_classdev *cdev) +{ + struct led_classdev_mc *mc = lcdev_to_mccdev(cdev); + struct lpg_led *led = container_of(mc, struct lpg_led, mcdev); + + return lpg_pattern_clear(led); +} + +static int lpg_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct lpg *lpg = container_of(chip, struct lpg, pwm); + struct lpg_channel *chan = &lpg->channels[pwm->hwpwm]; + + return chan->in_use ? -EBUSY : 0; +} + +/* + * Limitations: + * - Updating both duty and period is not done atomically, so the output signal + * will momentarily be a mix of the settings. + * - Changed parameters takes effect immediately. + * - A disabled channel outputs a logical 0. + */ +static int lpg_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct lpg *lpg = container_of(chip, struct lpg, pwm); + struct lpg_channel *chan = &lpg->channels[pwm->hwpwm]; + int ret = 0; + + if (state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + mutex_lock(&lpg->lock); + + if (state->enabled) { + ret = lpg_calc_freq(chan, state->period); + if (ret < 0) + goto out_unlock; + + lpg_calc_duty(chan, state->duty_cycle); + } + chan->enabled = state->enabled; + + lpg_apply(chan); + + triled_set(lpg, chan->triled_mask, chan->enabled ? chan->triled_mask : 0); + +out_unlock: + mutex_unlock(&lpg->lock); + + return ret; +} + +static void lpg_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm, + struct pwm_state *state) +{ + struct lpg *lpg = container_of(chip, struct lpg, pwm); + struct lpg_channel *chan = &lpg->channels[pwm->hwpwm]; + unsigned int pre_div; + unsigned int refclk; + unsigned int val; + unsigned int m; + u16 pwm_value; + int ret; + + ret = regmap_read(lpg->map, chan->base + LPG_SIZE_CLK_REG, &val); + if (ret) + return; + + refclk = lpg_clk_rates[val & PWM_CLK_SELECT_MASK]; + if (refclk) { + ret = regmap_read(lpg->map, chan->base + LPG_PREDIV_CLK_REG, &val); + if (ret) + return; + + pre_div = lpg_pre_divs[FIELD_GET(PWM_FREQ_PRE_DIV_MASK, val)]; + m = FIELD_GET(PWM_FREQ_EXP_MASK, val); + + ret = regmap_bulk_read(lpg->map, chan->base + PWM_VALUE_REG, &pwm_value, sizeof(pwm_value)); + if (ret) + return; + + state->period = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * LPG_RESOLUTION * pre_div * (1 << m), refclk); + state->duty_cycle = DIV_ROUND_UP_ULL((u64)NSEC_PER_SEC * pwm_value * pre_div * (1 << m), refclk); + } else { + state->period = 0; + state->duty_cycle = 0; + } + + ret = regmap_read(lpg->map, chan->base + PWM_ENABLE_CONTROL_REG, &val); + if (ret) + return; + + state->enabled = FIELD_GET(LPG_ENABLE_CONTROL_OUTPUT, val); + state->polarity = PWM_POLARITY_NORMAL; + + if (state->duty_cycle > state->period) + state->duty_cycle = state->period; +} + +static const struct pwm_ops lpg_pwm_ops = { + .request = lpg_pwm_request, + .apply = lpg_pwm_apply, + .get_state = lpg_pwm_get_state, + .owner = THIS_MODULE, +}; + +static int lpg_add_pwm(struct lpg *lpg) +{ + int ret; + + lpg->pwm.base = -1; + lpg->pwm.dev = lpg->dev; + lpg->pwm.npwm = lpg->num_channels; + lpg->pwm.ops = &lpg_pwm_ops; + + ret = pwmchip_add(&lpg->pwm); + if (ret) + dev_err(lpg->dev, "failed to add PWM chip: ret %d\n", ret); + + return ret; +} + +static int lpg_parse_channel(struct lpg *lpg, struct device_node *np, + struct lpg_channel **channel) +{ + struct lpg_channel *chan; + u32 color = LED_COLOR_ID_GREEN; + u32 reg; + int ret; + + ret = of_property_read_u32(np, "reg", ®); + if (ret || !reg || reg > lpg->num_channels) { + dev_err(lpg->dev, "invalid \"reg\" of %pOFn\n", np); + return -EINVAL; + } + + chan = &lpg->channels[reg - 1]; + chan->in_use = true; + + ret = of_property_read_u32(np, "color", &color); + if (ret < 0 && ret != -EINVAL) { + dev_err(lpg->dev, "failed to parse \"color\" of %pOF\n", np); + return ret; + } + + chan->color = color; + + *channel = chan; + + return 0; +} + +static int lpg_add_led(struct lpg *lpg, struct device_node *np) +{ + struct led_init_data init_data = {}; + struct led_classdev *cdev; + struct device_node *child; + struct mc_subled *info; + struct lpg_led *led; + const char *state; + int num_channels; + u32 color = 0; + int ret; + int i; + + ret = of_property_read_u32(np, "color", &color); + if (ret < 0 && ret != -EINVAL) { + dev_err(lpg->dev, "failed to parse \"color\" of %pOF\n", np); + return ret; + } + + if (color == LED_COLOR_ID_RGB) + num_channels = of_get_available_child_count(np); + else + num_channels = 1; + + led = devm_kzalloc(lpg->dev, struct_size(led, channels, num_channels), GFP_KERNEL); + if (!led) + return -ENOMEM; + + led->lpg = lpg; + led->num_channels = num_channels; + + if (color == LED_COLOR_ID_RGB) { + info = devm_kcalloc(lpg->dev, num_channels, sizeof(*info), GFP_KERNEL); + if (!info) + return -ENOMEM; + i = 0; + for_each_available_child_of_node(np, child) { + ret = lpg_parse_channel(lpg, child, &led->channels[i]); + if (ret < 0) + return ret; + + info[i].color_index = led->channels[i]->color; + info[i].intensity = 0; + i++; + } + + led->mcdev.subled_info = info; + led->mcdev.num_colors = num_channels; + + cdev = &led->mcdev.led_cdev; + cdev->brightness_set = lpg_brightness_mc_set; + cdev->blink_set = lpg_blink_mc_set; + + /* Register pattern accessors only if we have a LUT block */ + if (lpg->lut_base) { + cdev->pattern_set = lpg_pattern_mc_set; + cdev->pattern_clear = lpg_pattern_mc_clear; + } + } else { + ret = lpg_parse_channel(lpg, np, &led->channels[0]); + if (ret < 0) + return ret; + + cdev = &led->cdev; + cdev->brightness_set = lpg_brightness_single_set; + cdev->blink_set = lpg_blink_single_set; + + /* Register pattern accessors only if we have a LUT block */ + if (lpg->lut_base) { + cdev->pattern_set = lpg_pattern_single_set; + cdev->pattern_clear = lpg_pattern_single_clear; + } + } + + cdev->default_trigger = of_get_property(np, "linux,default-trigger", NULL); + cdev->max_brightness = LPG_RESOLUTION - 1; + + if (!of_property_read_string(np, "default-state", &state) && + !strcmp(state, "on")) + cdev->brightness = cdev->max_brightness; + else + cdev->brightness = LED_OFF; + + cdev->brightness_set(cdev, cdev->brightness); + + init_data.fwnode = of_fwnode_handle(np); + + if (color == LED_COLOR_ID_RGB) + ret = devm_led_classdev_multicolor_register_ext(lpg->dev, &led->mcdev, &init_data); + else + ret = devm_led_classdev_register_ext(lpg->dev, &led->cdev, &init_data); + if (ret) + dev_err(lpg->dev, "unable to register %s\n", cdev->name); + + return ret; +} + +static int lpg_init_channels(struct lpg *lpg) +{ + const struct lpg_data *data = lpg->data; + struct lpg_channel *chan; + int i; + + lpg->num_channels = data->num_channels; + lpg->channels = devm_kcalloc(lpg->dev, data->num_channels, + sizeof(struct lpg_channel), GFP_KERNEL); + if (!lpg->channels) + return -ENOMEM; + + for (i = 0; i < data->num_channels; i++) { + chan = &lpg->channels[i]; + + chan->lpg = lpg; + chan->base = data->channels[i].base; + chan->triled_mask = data->channels[i].triled_mask; + chan->lut_mask = BIT(i); + + regmap_read(lpg->map, chan->base + LPG_SUBTYPE_REG, &chan->subtype); + } + + return 0; +} + +static int lpg_init_triled(struct lpg *lpg) +{ + struct device_node *np = lpg->dev->of_node; + int ret; + + /* Skip initialization if we don't have a triled block */ + if (!lpg->data->triled_base) + return 0; + + lpg->triled_base = lpg->data->triled_base; + lpg->triled_has_atc_ctl = lpg->data->triled_has_atc_ctl; + lpg->triled_has_src_sel = lpg->data->triled_has_src_sel; + + if (lpg->triled_has_src_sel) { + ret = of_property_read_u32(np, "qcom,power-source", &lpg->triled_src); + if (ret || lpg->triled_src == 2 || lpg->triled_src > 3) { + dev_err(lpg->dev, "invalid power source\n"); + return -EINVAL; + } + } + + /* Disable automatic trickle charge LED */ + if (lpg->triled_has_atc_ctl) + regmap_write(lpg->map, lpg->triled_base + TRI_LED_ATC_CTL, 0); + + /* Configure power source */ + if (lpg->triled_has_src_sel) + regmap_write(lpg->map, lpg->triled_base + TRI_LED_SRC_SEL, lpg->triled_src); + + /* Default all outputs to off */ + regmap_write(lpg->map, lpg->triled_base + TRI_LED_EN_CTL, 0); + + return 0; +} + +static int lpg_init_lut(struct lpg *lpg) +{ + const struct lpg_data *data = lpg->data; + + if (!data->lut_base) + return 0; + + lpg->lut_base = data->lut_base; + lpg->lut_size = data->lut_size; + + lpg->lut_bitmap = devm_bitmap_zalloc(lpg->dev, lpg->lut_size, GFP_KERNEL); + if (!lpg->lut_bitmap) + return -ENOMEM; + + return 0; +} + +static int lpg_probe(struct platform_device *pdev) +{ + struct device_node *np; + struct lpg *lpg; + int ret; + int i; + + lpg = devm_kzalloc(&pdev->dev, sizeof(*lpg), GFP_KERNEL); + if (!lpg) + return -ENOMEM; + + lpg->data = of_device_get_match_data(&pdev->dev); + if (!lpg->data) + return -EINVAL; + + platform_set_drvdata(pdev, lpg); + + lpg->dev = &pdev->dev; + mutex_init(&lpg->lock); + + lpg->map = dev_get_regmap(pdev->dev.parent, NULL); + if (!lpg->map) + return dev_err_probe(&pdev->dev, -ENXIO, "parent regmap unavailable\n"); + + ret = lpg_init_channels(lpg); + if (ret < 0) + return ret; + + ret = lpg_parse_dtest(lpg); + if (ret < 0) + return ret; + + ret = lpg_init_triled(lpg); + if (ret < 0) + return ret; + + ret = lpg_init_lut(lpg); + if (ret < 0) + return ret; + + for_each_available_child_of_node(pdev->dev.of_node, np) { + ret = lpg_add_led(lpg, np); + if (ret) + return ret; + } + + for (i = 0; i < lpg->num_channels; i++) + lpg_apply_dtest(&lpg->channels[i]); + + return lpg_add_pwm(lpg); +} + +static int lpg_remove(struct platform_device *pdev) +{ + struct lpg *lpg = platform_get_drvdata(pdev); + + pwmchip_remove(&lpg->pwm); + + return 0; +} + +static const struct lpg_data pm8916_pwm_data = { + .num_channels = 1, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xbc00 }, + }, +}; + +static const struct lpg_data pm8941_lpg_data = { + .lut_base = 0xb000, + .lut_size = 64, + + .triled_base = 0xd000, + .triled_has_atc_ctl = true, + .triled_has_src_sel = true, + + .num_channels = 8, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xb100 }, + { .base = 0xb200 }, + { .base = 0xb300 }, + { .base = 0xb400 }, + { .base = 0xb500, .triled_mask = BIT(5) }, + { .base = 0xb600, .triled_mask = BIT(6) }, + { .base = 0xb700, .triled_mask = BIT(7) }, + { .base = 0xb800 }, + }, +}; + +static const struct lpg_data pm8994_lpg_data = { + .lut_base = 0xb000, + .lut_size = 64, + + .num_channels = 6, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xb100 }, + { .base = 0xb200 }, + { .base = 0xb300 }, + { .base = 0xb400 }, + { .base = 0xb500 }, + { .base = 0xb600 }, + }, +}; + +static const struct lpg_data pmi8994_lpg_data = { + .lut_base = 0xb000, + .lut_size = 24, + + .triled_base = 0xd000, + .triled_has_atc_ctl = true, + .triled_has_src_sel = true, + + .num_channels = 4, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xb100, .triled_mask = BIT(5) }, + { .base = 0xb200, .triled_mask = BIT(6) }, + { .base = 0xb300, .triled_mask = BIT(7) }, + { .base = 0xb400 }, + }, +}; + +static const struct lpg_data pmi8998_lpg_data = { + .lut_base = 0xb000, + .lut_size = 49, + + .triled_base = 0xd000, + + .num_channels = 6, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xb100 }, + { .base = 0xb200 }, + { .base = 0xb300, .triled_mask = BIT(5) }, + { .base = 0xb400, .triled_mask = BIT(6) }, + { .base = 0xb500, .triled_mask = BIT(7) }, + { .base = 0xb600 }, + }, +}; + +static const struct lpg_data pm8150b_lpg_data = { + .lut_base = 0xb000, + .lut_size = 24, + + .triled_base = 0xd000, + + .num_channels = 2, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xb100, .triled_mask = BIT(7) }, + { .base = 0xb200, .triled_mask = BIT(6) }, + }, +}; + +static const struct lpg_data pm8150l_lpg_data = { + .lut_base = 0xb000, + .lut_size = 48, + + .triled_base = 0xd000, + + .num_channels = 5, + .channels = (const struct lpg_channel_data[]) { + { .base = 0xb100, .triled_mask = BIT(7) }, + { .base = 0xb200, .triled_mask = BIT(6) }, + { .base = 0xb300, .triled_mask = BIT(5) }, + { .base = 0xbc00 }, + { .base = 0xbd00 }, + + }, +}; + +static const struct of_device_id lpg_of_table[] = { + { .compatible = "qcom,pm8150b-lpg", .data = &pm8150b_lpg_data }, + { .compatible = "qcom,pm8150l-lpg", .data = &pm8150l_lpg_data }, + { .compatible = "qcom,pm8916-pwm", .data = &pm8916_pwm_data }, + { .compatible = "qcom,pm8941-lpg", .data = &pm8941_lpg_data }, + { .compatible = "qcom,pm8994-lpg", .data = &pm8994_lpg_data }, + { .compatible = "qcom,pmi8994-lpg", .data = &pmi8994_lpg_data }, + { .compatible = "qcom,pmi8998-lpg", .data = &pmi8998_lpg_data }, + { .compatible = "qcom,pmc8180c-lpg", .data = &pm8150l_lpg_data }, + {} +}; +MODULE_DEVICE_TABLE(of, lpg_of_table); + +static struct platform_driver lpg_driver = { + .probe = lpg_probe, + .remove = lpg_remove, + .driver = { + .name = "qcom-spmi-lpg", + .of_match_table = lpg_of_table, + }, +}; +module_platform_driver(lpg_driver); + +MODULE_DESCRIPTION("Qualcomm LPG LED driver"); +MODULE_LICENSE("GPL v2"); |