@@ -641,6 +641,13 @@ config LEDS_POWERNV
To compile this driver as a module, choose 'm' here: the module
will be called leds-powernv.
+config LEDS_QCOM_LPG
+ tristate "LED support for Qualcomm LPG"
+ depends on LEDS_CLASS
+ help
+ This option enables support for the Light Pulse Generator found in a
+ wide variety of Qualcomm PMICs.
+
config LEDS_SYSCON
bool "LED support for LEDs on system controllers"
depends on LEDS_CLASS=y
@@ -61,6 +61,9 @@ obj-$(CONFIG_LEDS_MAX77693) += leds-max77693.o
obj-$(CONFIG_LEDS_MAX8997) += leds-max8997.o
obj-$(CONFIG_LEDS_LM355x) += leds-lm355x.o
obj-$(CONFIG_LEDS_BLINKM) += leds-blinkm.o
+obj-$(CONFIG_LEDS_QCOM_LPG) += leds-qcom-lpg.o
+obj-$(CONFIG_LEDS_QCOM_LPG) += leds-qcom-lpg-lut.o
+obj-$(CONFIG_LEDS_QCOM_LPG) += leds-qcom-triled.o
obj-$(CONFIG_LEDS_SYSCON) += leds-syscon.o
obj-$(CONFIG_LEDS_VERSATILE) += leds-versatile.o
obj-$(CONFIG_LEDS_MENF21BMC) += leds-menf21bmc.o
new file mode 100644
@@ -0,0 +1,296 @@
+/* Copyright (c) 2017 Linaro Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "leds-qcom-lpg.h"
+
+#define LPG_LUT_REG(x) (0x40 + (x) * 2)
+#define RAMP_CONTROL_REG 0xc8
+
+static struct platform_driver lpg_lut_driver;
+
+/*
+ * lpg_lut_dev - LUT device context
+ * @dev: struct device for the LUT device
+ * @map: regmap for register access
+ * @reg: base address for the LUT block
+ * @size: number of LUT entries in LUT block
+ * @bitmap: bitmap tracking occupied LUT entries
+ */
+struct lpg_lut_dev {
+ struct device *dev;
+ struct regmap *map;
+
+ u32 reg;
+ u32 size;
+
+ unsigned long bitmap[];
+};
+
+/*
+ * qcom_lpg_lut - context for a client and LUT device pair
+ * @ldev: reference to a LUT device
+ * @start_mask: mask of bits to use for synchronizing ramp generators
+ */
+struct qcom_lpg_lut {
+ struct lpg_lut_dev *ldev;
+ int start_mask;
+};
+
+static void lpg_lut_release(struct device *dev, void *res)
+{
+ struct qcom_lpg_lut *lut = res;
+
+ put_device(lut->ldev->dev);
+}
+
+/**
+ * qcom_lpg_lut_get() - acquire a handle to the LUT implementation
+ * @dev: struct device reference of the client
+ *
+ * Returns a LUT context, or ERR_PTR on failure.
+ */
+struct qcom_lpg_lut *qcom_lpg_lut_get(struct device *dev)
+{
+ struct platform_device *pdev;
+ struct device_node *lut_node;
+ struct qcom_lpg_lut *lut;
+ u32 cell;
+ int ret;
+
+ lut_node = of_parse_phandle(dev->of_node, "qcom,lut", 0);
+ if (!lut_node)
+ return NULL;
+
+ ret = of_property_read_u32(dev->of_node, "qcom,lpg-channel", &cell);
+ if (ret) {
+ dev_err(dev, "lpg without qcom,lpg-channel\n");
+ return ERR_PTR(ret);
+ }
+
+ pdev = of_find_device_by_node(lut_node);
+ of_node_put(lut_node);
+ if (!pdev || !pdev->dev.driver)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ if (pdev->dev.driver != &lpg_lut_driver.driver) {
+ dev_err(dev, "referenced node is not a lpg lut\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ lut = devres_alloc(lpg_lut_release, sizeof(*lut), GFP_KERNEL);
+ if (!lut)
+ return ERR_PTR(-ENOMEM);
+
+ lut->ldev = platform_get_drvdata(pdev);
+ lut->start_mask = BIT(cell - 1);
+
+ devres_add(dev, lut);
+
+ return lut;
+}
+EXPORT_SYMBOL_GPL(qcom_lpg_lut_get);
+
+/**
+ * qcom_lpg_lut_store() - store a sequence of levels in the LUT
+ * @lut: LUT context acquired from qcom_lpg_lut_get()
+ * @values: an array of values, in the range 0 <= x < 512
+ * @len: length of the @values array
+ *
+ * Returns a qcom_lpg_pattern object, or ERR_PTR on failure.
+ *
+ * Patterns must be freed by calling qcom_lpg_lut_free()
+ */
+struct qcom_lpg_pattern *qcom_lpg_lut_store(struct qcom_lpg_lut *lut,
+ const u16 *values, size_t len)
+{
+ struct qcom_lpg_pattern *pattern;
+ struct lpg_lut_dev *ldev = lut->ldev;
+ unsigned long lo_idx;
+ u8 val[2];
+ int i;
+
+ /* Hardware does not behave when LO_IDX == HI_IDX */
+ if (len == 1)
+ return ERR_PTR(-EINVAL);
+
+ lo_idx = bitmap_find_next_zero_area(ldev->bitmap, ldev->size, 0, len, 0);
+ if (lo_idx >= ldev->size)
+ return ERR_PTR(-ENOMEM);
+
+ pattern = kzalloc(sizeof(*pattern), GFP_KERNEL);
+ if (!pattern)
+ return ERR_PTR(-ENOMEM);
+
+ pattern->lut = lut;
+ pattern->lo_idx = lo_idx;
+ pattern->hi_idx = lo_idx + len - 1;
+
+ for (i = 0; i < len; i++) {
+ val[0] = values[i] & 0xff;
+ val[1] = values[i] >> 8;
+
+ regmap_bulk_write(ldev->map,
+ ldev->reg + LPG_LUT_REG(lo_idx + i), val, 2);
+ }
+
+ bitmap_set(ldev->bitmap, lo_idx, len);
+
+ return pattern;
+}
+EXPORT_SYMBOL_GPL(qcom_lpg_lut_store);
+
+/**
+ * qcom_lpg_lut_read() - read the data points from a pattern
+ * @pattern: pattern to be read
+ * @len: to be filled in with length of the pattern
+ *
+ * Returns an allocated u16 array of brightness values, NULL if no pattern
+ * specified or ERR_PTR() on failure. Caller must free the returned array.
+ */
+u16 *qcom_lpg_lut_read(struct qcom_lpg_pattern *pattern, size_t *len)
+{
+ struct qcom_lpg_lut *lut;
+ struct lpg_lut_dev *ldev;
+ unsigned long lo_idx;
+ u16 *values;
+ u8 val[2];
+ int ret;
+ int i;
+
+ if (!pattern)
+ return NULL;
+
+ lut = pattern->lut;
+ ldev = lut->ldev;
+ lo_idx = pattern->lo_idx;
+
+ *len = pattern->hi_idx - pattern->lo_idx + 1;
+
+ values = kcalloc(*len, sizeof(u16), GFP_KERNEL);
+ if (!values)
+ return ERR_PTR(-ENOMEM);
+
+ for (i = 0; i < *len; i++) {
+ ret = regmap_bulk_read(ldev->map,
+ ldev->reg + LPG_LUT_REG(lo_idx + i),
+ &val, 2);
+ if (ret < 0) {
+ kfree(values);
+ return ERR_PTR(ret);
+ }
+
+ values[i] = val[0] | val[1] << 8;
+ }
+
+ return values;
+}
+EXPORT_SYMBOL_GPL(qcom_lpg_lut_read);
+
+/**
+ * qcom_lpg_lut_free() - release LUT pattern and free entries
+ * @pattern: reference to pattern to release
+ */
+void qcom_lpg_lut_free(struct qcom_lpg_pattern *pattern)
+{
+ struct qcom_lpg_lut *lut;
+ struct lpg_lut_dev *ldev;
+ int len;
+
+ if (!pattern)
+ return;
+
+ lut = pattern->lut;
+ ldev = lut->ldev;
+
+ len = pattern->hi_idx - pattern->lo_idx + 1;
+ bitmap_clear(ldev->bitmap, pattern->lo_idx, len);
+}
+EXPORT_SYMBOL_GPL(qcom_lpg_lut_free);
+
+/**
+ * qcom_lpg_lut_sync() - (re)start the ramp generator, to sync pattern
+ * @lut: LUT device reference, to sync
+ */
+int qcom_lpg_lut_sync(struct qcom_lpg_lut *lut)
+{
+ struct lpg_lut_dev *ldev = lut->ldev;
+
+ return regmap_update_bits(ldev->map, ldev->reg + RAMP_CONTROL_REG,
+ lut->start_mask, 0xff);
+}
+EXPORT_SYMBOL_GPL(qcom_lpg_lut_sync);
+
+static int lpg_lut_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct lpg_lut_dev *ldev;
+ size_t bitmap_size;
+ u32 size;
+ int ret;
+
+ ret = of_property_read_u32(np, "qcom,lut-size", &size);
+ if (ret) {
+ dev_err(&pdev->dev, "invalid LUT size\n");
+ return -EINVAL;
+ }
+
+ bitmap_size = BITS_TO_LONGS(size) / sizeof(unsigned long);
+ ldev = devm_kzalloc(&pdev->dev, sizeof(*ldev) + bitmap_size, GFP_KERNEL);
+ if (!ldev)
+ return -ENOMEM;
+
+ ldev->dev = &pdev->dev;
+ ldev->size = size;
+
+ ldev->map = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!ldev->map) {
+ dev_err(&pdev->dev, "parent regmap unavailable\n");
+ return -ENXIO;
+ }
+
+ ret = of_property_read_u32(np, "reg", &ldev->reg);
+ if (ret) {
+ dev_err(&pdev->dev, "no register offset specified\n");
+ return -EINVAL;
+ }
+
+ platform_set_drvdata(pdev, ldev);
+
+ return 0;
+}
+
+static const struct of_device_id lpg_lut_of_table[] = {
+ { .compatible = "qcom,spmi-lpg-lut" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, lpg_lut_of_table);
+
+static struct platform_driver lpg_lut_driver = {
+ .probe = lpg_lut_probe,
+ .driver = {
+ .name = "qcom_lpg_lut",
+ .of_match_table = lpg_lut_of_table,
+ },
+};
+module_platform_driver(lpg_lut_driver);
+
+MODULE_DESCRIPTION("Qualcomm TRI LED driver");
+MODULE_LICENSE("GPL v2");
new file mode 100644
@@ -0,0 +1,782 @@
+/*
+ * Copyright (c) 2017 Linaro Ltd
+ * Copyright (c) 2010-2012, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "leds-qcom-lpg.h"
+
+#define LPG_PATTERN_CONFIG_REG 0x40
+#define LPG_SIZE_CLK_REG 0x41
+#define LPG_PREDIV_CLK_REG 0x42
+#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)
+
+/*
+ * lpg - LPG device context
+ * @dev: struct device for LPG device
+ * @map: regmap for register access
+ * @reg: base address of the LPG device
+ * @dtest_line: DTEST line for output, or 0 if disabled
+ * @dtest_value: DTEST line configuration
+ * @is_lpg: operating as LPG, in contrast to simple PWM
+ * @cdev: LED class object
+ * @tri_led: reference to TRILED color object, optional
+ * @chip: PWM-chip object, if operating in PWM mode
+ * @period_us: period (in microseconds) of the generated pulses
+ * @pwm_value: duty (in microseconds) of the generated pulses, overriden by LUT
+ * @enabled: output enabled?
+ * @pwm_size: resolution of the @pwm_value, 6 or 9 bits
+ * @clk: base frequency of the clock generator
+ * @pre_div: divider of @clk
+ * @pre_div_exp: exponential divider of @clk
+ * @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_duration_ms: length (in milliseconds) of one pattern run
+ * @ramp_lo_pause_ms: pause (in milliseconds) before iterating over pattern
+ * @ramp_hi_pause_ms: pause (in milliseconds) after iterating over pattern
+ * @lut: LUT context reference
+ * @pattern: reference to allocated pattern with LUT
+ */
+
+struct lpg {
+ struct device *dev;
+ struct regmap *map;
+
+ u32 reg;
+ int dtest_line;
+ int dtest_value;
+
+ bool is_lpg;
+
+ struct led_classdev cdev;
+
+ struct qcom_tri_led *tri_led;
+
+ struct pwm_chip chip;
+
+ unsigned int period_us;
+
+ u16 pwm_value;
+ bool enabled;
+
+ unsigned int pwm_size;
+ unsigned int clk;
+ unsigned int pre_div;
+ unsigned int pre_div_exp;
+
+ bool ramp_enabled;
+ bool ramp_ping_pong;
+ bool ramp_oneshot;
+ bool ramp_reverse;
+ unsigned long ramp_duration_ms;
+ unsigned long ramp_lo_pause_ms;
+ unsigned long ramp_hi_pause_ms;
+
+ struct qcom_lpg_lut *lut;
+ struct qcom_lpg_pattern *pattern;
+};
+
+#define NUM_PWM_PREDIV 4
+#define NUM_PWM_CLK 3
+#define NUM_EXP 7
+
+static const unsigned int lpg_clk_table[NUM_PWM_PREDIV][NUM_PWM_CLK] = {
+ {
+ 1 * (NSEC_PER_SEC / 1024),
+ 1 * (NSEC_PER_SEC / 32768),
+ 1 * (NSEC_PER_SEC / 19200000),
+ },
+ {
+ 3 * (NSEC_PER_SEC / 1024),
+ 3 * (NSEC_PER_SEC / 32768),
+ 3 * (NSEC_PER_SEC / 19200000),
+ },
+ {
+ 5 * (NSEC_PER_SEC / 1024),
+ 5 * (NSEC_PER_SEC / 32768),
+ 5 * (NSEC_PER_SEC / 19200000),
+ },
+ {
+ 6 * (NSEC_PER_SEC / 1024),
+ 6 * (NSEC_PER_SEC / 32768),
+ 6 * (NSEC_PER_SEC / 19200000),
+ },
+};
+
+/*
+ * PWM Frequency = Clock Frequency / (N * T)
+ * or
+ * PWM Period = Clock Period * (N * T)
+ * where
+ * N = 2^9 or 2^6 for 9-bit or 6-bit PWM size
+ * T = Pre-divide * 2^m, where m = 0..7 (exponent)
+ *
+ * This is the formula to figure out m for the best pre-divide and clock:
+ * (PWM Period / N) = (Pre-divide * Clock Period) * 2^m
+ */
+static void lpg_calc_freq(struct lpg *lpg, unsigned int period_us)
+{
+ int n, m, clk, div;
+ int best_m, best_div, best_clk;
+ unsigned int last_err, cur_err, min_err;
+ unsigned int tmp_p, period_n;
+
+ if (period_us == lpg->period_us)
+ return;
+
+ /* PWM Period / N */
+ if (period_us < ((unsigned int)(-1) / NSEC_PER_USEC)) {
+ period_n = (period_us * NSEC_PER_USEC) >> 6;
+ n = 6;
+ } else {
+ period_n = (period_us >> 9) * NSEC_PER_USEC;
+ n = 9;
+ }
+
+ min_err = last_err = (unsigned int)(-1);
+ best_m = 0;
+ best_clk = 0;
+ best_div = 0;
+ for (clk = 0; clk < NUM_PWM_CLK; clk++) {
+ for (div = 0; div < NUM_PWM_PREDIV; div++) {
+ /* period_n = (PWM Period / N) */
+ /* tmp_p = (Pre-divide * Clock Period) * 2^m */
+ tmp_p = lpg_clk_table[div][clk];
+ for (m = 0; m <= NUM_EXP; m++) {
+ if (period_n > tmp_p)
+ cur_err = period_n - tmp_p;
+ else
+ cur_err = tmp_p - period_n;
+
+ if (cur_err < min_err) {
+ min_err = cur_err;
+ best_m = m;
+ best_clk = clk;
+ best_div = div;
+ }
+
+ if (m && cur_err > last_err)
+ /* Break for bigger cur_err */
+ break;
+
+ last_err = cur_err;
+ tmp_p <<= 1;
+ }
+ }
+ }
+
+ /* Use higher resolution */
+ if (best_m >= 3 && n == 6) {
+ n += 3;
+ best_m -= 3;
+ }
+
+ lpg->clk = best_clk;
+ lpg->pre_div = best_div;
+ lpg->pre_div_exp = best_m;
+ lpg->pwm_size = n;
+
+ lpg->period_us = period_us;
+}
+
+static void lpg_calc_duty(struct lpg *lpg, unsigned long duty_us)
+{
+ unsigned long max = (1 << lpg->pwm_size) - 1;
+ unsigned long val;
+
+ /* Figure out pwm_value with overflow handling */
+ if (duty_us < 1 << (sizeof(val) * 8 - lpg->pwm_size))
+ val = (duty_us << lpg->pwm_size) / lpg->period_us;
+ else
+ val = duty_us / (lpg->period_us >> lpg->pwm_size);
+
+ if (val > max)
+ val = max;
+
+ lpg->pwm_value = val;
+}
+
+#define LPG_RESOLUTION_9BIT BIT(4)
+
+static void lpg_apply_freq(struct lpg *lpg)
+{
+ unsigned long val;
+
+ if (!lpg->enabled)
+ return;
+
+ /* Clock register values are off-by-one from lpg_clk_table */
+ val = lpg->clk + 1;
+
+ if (lpg->pwm_size == 9)
+ val |= LPG_RESOLUTION_9BIT;
+ regmap_write(lpg->map, lpg->reg + LPG_SIZE_CLK_REG, val);
+
+ val = lpg->pre_div << 5 | lpg->pre_div_exp;
+ regmap_write(lpg->map, lpg->reg + LPG_PREDIV_CLK_REG, val);
+}
+
+#define LPG_ENABLE_GLITCH_REMOVAL BIT(5)
+
+static void lpg_enable_glitch(struct lpg *lpg)
+{
+ regmap_update_bits(lpg->map, lpg->reg + PWM_TYPE_CONFIG_REG,
+ LPG_ENABLE_GLITCH_REMOVAL, 0);
+}
+
+static void lpg_disable_glitch(struct lpg *lpg)
+{
+ regmap_update_bits(lpg->map, lpg->reg + PWM_TYPE_CONFIG_REG,
+ LPG_ENABLE_GLITCH_REMOVAL,
+ LPG_ENABLE_GLITCH_REMOVAL);
+}
+
+static void lpg_apply_pwm_value(struct lpg *lpg)
+{
+ u8 val[] = { lpg->pwm_value & 0xff, lpg->pwm_value >> 8 };
+
+ if (!lpg->enabled)
+ return;
+
+ regmap_bulk_write(lpg->map, lpg->reg + PWM_VALUE_REG, val, 2);
+}
+
+#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 *lpg)
+{
+ struct qcom_lpg_pattern *pattern = lpg->pattern;
+ unsigned int hi_pause;
+ unsigned int lo_pause;
+ unsigned int step;
+ unsigned int conf = 0;
+ int pattern_len;
+
+ if (!lpg->ramp_enabled || !pattern)
+ return;
+
+ pattern_len = pattern->hi_idx - pattern->lo_idx + 1;
+
+ step = DIV_ROUND_UP(lpg->ramp_duration_ms, pattern_len);
+ hi_pause = DIV_ROUND_UP(lpg->ramp_hi_pause_ms, step);
+ lo_pause = DIV_ROUND_UP(lpg->ramp_lo_pause_ms, step);
+
+ if (!lpg->ramp_reverse)
+ conf |= LPG_PATTERN_CONFIG_LO_TO_HI;
+ if (!lpg->ramp_oneshot)
+ conf |= LPG_PATTERN_CONFIG_REPEAT;
+ if (lpg->ramp_ping_pong)
+ conf |= LPG_PATTERN_CONFIG_TOGGLE;
+ if (lpg->ramp_hi_pause_ms)
+ conf |= LPG_PATTERN_CONFIG_PAUSE_HI;
+ if (lpg->ramp_lo_pause_ms)
+ conf |= LPG_PATTERN_CONFIG_PAUSE_LO;
+
+ regmap_write(lpg->map, lpg->reg + LPG_PATTERN_CONFIG_REG, conf);
+ regmap_write(lpg->map, lpg->reg + LPG_HI_IDX_REG, pattern->hi_idx);
+ regmap_write(lpg->map, lpg->reg + LPG_LO_IDX_REG, pattern->lo_idx);
+
+ regmap_write(lpg->map, lpg->reg + LPG_RAMP_DURATION_REG, step);
+ regmap_write(lpg->map, lpg->reg + LPG_HI_PAUSE_REG, hi_pause);
+ regmap_write(lpg->map, lpg->reg + LPG_LO_PAUSE_REG, lo_pause);
+
+ /* Trigger start of ramp generator(s) */
+ qcom_lpg_lut_sync(lpg->lut);
+}
+
+#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 *lpg)
+{
+ unsigned int ctrl;
+
+ ctrl = LPG_ENABLE_CONTROL_BUFFER_TRISTATE;
+
+ if (lpg->enabled)
+ ctrl |= LPG_ENABLE_CONTROL_OUTPUT;
+
+ if (lpg->pattern)
+ ctrl |= LPG_ENABLE_CONTROL_RAMP_GEN;
+ else
+ ctrl |= LPG_ENABLE_CONTROL_SRC_PWM;
+
+ regmap_write(lpg->map, lpg->reg + 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 (lpg->enabled)
+ lpg_apply_pwm_value(lpg);
+}
+
+#define LPG_SYNC_PWM BIT(0)
+
+static void lpg_apply_sync(struct lpg *lpg)
+{
+ regmap_write(lpg->map, lpg->reg + PWM_SYNC_REG, LPG_SYNC_PWM);
+}
+
+static void lpg_apply_dtest(struct lpg *lpg)
+{
+ if (!lpg->dtest_line)
+ return;
+
+ regmap_write(lpg->map, lpg->reg + PWM_SEC_ACCESS_REG, 0xa5);
+ regmap_write(lpg->map, lpg->reg + PWM_DTEST_REG(lpg->dtest_line),
+ lpg->dtest_value);
+}
+
+static void lpg_apply(struct lpg *lpg)
+{
+ lpg_disable_glitch(lpg);
+ lpg_apply_freq(lpg);
+ lpg_apply_pwm_value(lpg);
+ lpg_apply_control(lpg);
+ lpg_apply_sync(lpg);
+ lpg_apply_lut_control(lpg);
+ lpg_enable_glitch(lpg);
+
+ if (lpg->tri_led)
+ qcom_tri_led_set(lpg->tri_led, lpg->enabled);
+}
+
+static void lpg_brightness_set(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ struct lpg *lpg = container_of(cdev, struct lpg, cdev);
+ unsigned int duty_us;
+
+ if (value == LED_OFF) {
+ lpg->enabled = false;
+ lpg->ramp_enabled = false;
+ } else if (lpg->pattern) {
+ lpg_calc_freq(lpg, NSEC_PER_USEC);
+
+ lpg->enabled = true;
+ lpg->ramp_enabled = true;
+ } else {
+ lpg_calc_freq(lpg, NSEC_PER_USEC);
+
+ duty_us = value * lpg->period_us / cdev->max_brightness;
+ lpg_calc_duty(lpg, duty_us);
+ lpg->enabled = true;
+ lpg->ramp_enabled = false;
+ }
+
+ lpg_apply(lpg);
+}
+
+static enum led_brightness lpg_brightness_get(struct led_classdev *cdev)
+{
+ struct lpg *lpg = container_of(cdev, struct lpg, cdev);
+ unsigned long max = (1 << lpg->pwm_size) - 1;
+
+ if (!lpg->enabled)
+ return LED_OFF;
+ else if (lpg->pattern)
+ return LED_FULL;
+ else
+ return lpg->pwm_value * cdev->max_brightness / max;
+}
+
+static int lpg_blink_set(struct led_classdev *cdev,
+ unsigned long *delay_on, unsigned long *delay_off)
+{
+ struct lpg *lpg = container_of(cdev, struct lpg, cdev);
+ unsigned int period_us;
+ unsigned int duty_us;
+
+ if (!*delay_on && !*delay_off) {
+ *delay_on = 500;
+ *delay_off = 500;
+ }
+
+ duty_us = *delay_on * USEC_PER_MSEC;
+ period_us = (*delay_on + *delay_off) * USEC_PER_MSEC;
+
+ lpg_calc_freq(lpg, period_us);
+ lpg_calc_duty(lpg, duty_us);
+
+ lpg->enabled = true;
+ lpg->ramp_enabled = false;
+
+ lpg_apply(lpg);
+
+ return 0;
+}
+
+#define interpolate(x1, y1, x2, y2, x) \
+ ((y1) + ((y2) - (y1)) * ((x) - (x1)) / ((x2) - (x1)))
+
+static int lpg_pattern_set(struct led_classdev *led_cdev,
+ struct led_pattern *led_pattern, int len,
+ bool repeat)
+{
+ struct lpg *lpg = container_of(led_cdev, struct lpg, cdev);
+ struct qcom_lpg_pattern *new_pattern;
+ unsigned int duration = 0;
+ unsigned int min_delta = (unsigned int)-1;
+ unsigned int hi_pause;
+ unsigned int lo_pause = 0;
+ unsigned int max = (1 << lpg->pwm_size) - 1;
+ bool ping_pong = true;
+ int brightness_a;
+ int brightness_b;
+ u16 *pattern;
+ int src_idx;
+ int dst_idx;
+ int step_t;
+ int time_a;
+ int time_b;
+ int value;
+ int steps;
+ int ret = 0;
+
+ /*
+ * The led_pattern specifies brightness values, potentially distributed
+ * unevenly over the duration of the pattern. The LPG only support
+ * evenly distributed values, so we interpolate new values from the
+ * led_pattern.
+ */
+
+ /* Sum the duration over the inner delta_ts and the tail is hi_pause */
+ for (src_idx = 0; src_idx < len - 1; src_idx++)
+ duration += led_pattern[src_idx].delta_t;
+ hi_pause = led_pattern[src_idx].delta_t;
+
+ for (src_idx = 0; src_idx < len; src_idx++) {
+ min_delta = min_t(unsigned int, min_delta,
+ led_pattern[src_idx].delta_t);
+ }
+
+ steps = duration / min_delta + 1;
+ pattern = kcalloc(steps, sizeof(*pattern), GFP_KERNEL);
+ if (!pattern)
+ return -ENOMEM;
+
+ time_a = 0;
+ for (src_idx = 0, dst_idx = 0; dst_idx < steps; dst_idx++) {
+ /* The timestamp of this evenly distributed data point */
+ step_t = dst_idx * min_delta;
+
+ /*
+ * Find time_a - time_b interval from source pattern that spans
+ * step_t
+ */
+ while (time_a + led_pattern[src_idx].delta_t < step_t) {
+ if (src_idx >= len - 1)
+ break;
+ time_a += led_pattern[++src_idx].delta_t;
+ }
+
+ if (src_idx < len - 1) {
+ time_b = time_a + led_pattern[src_idx].delta_t;
+
+ brightness_a = led_pattern[src_idx].brightness;
+ brightness_b = led_pattern[src_idx + 1].brightness;
+
+ /* Interpolate over the source pattern segment */
+ value = interpolate(time_a, brightness_a, time_b,
+ brightness_b, step_t);
+ } else {
+ value = led_pattern[src_idx].brightness;
+ }
+
+ /* Scale calculated value to the hardware brightness value */
+ pattern[dst_idx] = value * max / led_cdev->max_brightness;
+ }
+
+ /* Detect palindromes and use "ping pong" to reduce LUT usage */
+ for (dst_idx = 0; dst_idx < steps / 2; dst_idx++) {
+ if (pattern[dst_idx] != pattern[len - dst_idx - 1]) {
+ ping_pong = false;
+ break;
+ }
+ }
+ if (ping_pong) {
+ steps = (steps + 1) / 2;
+
+ /*
+ * When ping_pong is set the hi_pause will happen in the middle
+ * of the pattern, so we need to use lo_pause to delay between
+ * the loops.
+ */
+ if (repeat)
+ lo_pause = hi_pause;
+
+ hi_pause = 0;
+ }
+
+ new_pattern = qcom_lpg_lut_store(lpg->lut, pattern, steps);
+ if (IS_ERR(new_pattern)) {
+ ret = PTR_ERR(new_pattern);
+ goto out;
+ }
+
+ qcom_lpg_lut_free(lpg->pattern);
+
+ lpg->pattern = new_pattern;
+ lpg->ramp_duration_ms = duration;
+ lpg->ramp_ping_pong = ping_pong;
+ lpg->ramp_oneshot = !repeat;
+
+ lpg->ramp_lo_pause_ms = lo_pause;
+ lpg->ramp_hi_pause_ms = hi_pause;
+
+out:
+ kfree(pattern);
+
+ return ret;
+}
+
+static int lpg_pattern_clear(struct led_classdev *cdev)
+{
+ struct lpg *lpg = container_of(cdev, struct lpg, cdev);
+
+ qcom_lpg_lut_free(lpg->pattern);
+ lpg->pattern = NULL;
+
+ return 0;
+}
+
+static struct led_pattern *lpg_pattern_get(struct led_classdev *cdev,
+ size_t *len, bool *repeat)
+{
+ struct led_pattern *led_pattern;
+ struct lpg *lpg = container_of(cdev, struct lpg, cdev);
+ unsigned int delta_t;
+ unsigned int max = (1 << lpg->pwm_size) - 1;
+ size_t all_steps;
+ size_t steps;
+ u16 *pattern;
+ size_t i;
+ u16 val;
+
+ pattern = qcom_lpg_lut_read(lpg->pattern, &steps);
+ if (IS_ERR_OR_NULL(pattern))
+ return ERR_CAST(pattern);
+
+ all_steps = lpg->ramp_ping_pong ? steps * 2 - 1 : steps;
+
+ delta_t = (lpg->ramp_duration_ms + lpg->ramp_hi_pause_ms) / all_steps;
+
+ led_pattern = kcalloc(all_steps, sizeof(*pattern), GFP_KERNEL);
+ if (!led_pattern) {
+ led_pattern = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+
+ for (i = 0; i < all_steps; i++) {
+ if (i < steps)
+ val = pattern[i];
+ else
+ val = pattern[steps - i];
+
+ led_pattern[i].delta_t = delta_t;
+ led_pattern[i].brightness = val * cdev->max_brightness / max;
+ }
+
+ *len = all_steps;
+ *repeat = !lpg->ramp_oneshot;
+
+out:
+ kfree(pattern);
+ return led_pattern;
+}
+
+static int lpg_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct lpg *lpg = container_of(chip, struct lpg, chip);
+
+ lpg_calc_freq(lpg, state->period / NSEC_PER_USEC);
+ lpg_calc_duty(lpg, state->duty_cycle / NSEC_PER_USEC);
+ lpg->enabled = state->enabled;
+
+ lpg_apply(lpg);
+
+ state->polarity = PWM_POLARITY_NORMAL;
+ state->period = lpg->period_us * NSEC_PER_USEC;
+
+ return 0;
+}
+
+static const struct pwm_ops lpg_pwm_ops = {
+ .apply = lpg_pwm_apply,
+ .owner = THIS_MODULE,
+};
+
+static int lpg_register_pwm(struct lpg *lpg)
+{
+ int ret;
+
+ lpg->chip.base = -1;
+ lpg->chip.dev = lpg->dev;
+ lpg->chip.npwm = 1;
+ lpg->chip.ops = &lpg_pwm_ops;
+
+ ret = pwmchip_add(&lpg->chip);
+ if (ret)
+ dev_err(lpg->dev, "failed to add PWM chip: ret %d\n", ret);
+
+ return ret;
+}
+
+static int lpg_register_led(struct lpg *lpg)
+{
+ struct device_node *np = lpg->dev->of_node;
+ const char *state;
+ int ret;
+
+ lpg->lut = qcom_lpg_lut_get(lpg->dev);
+ if (IS_ERR(lpg->lut))
+ return PTR_ERR(lpg->lut);
+
+ /* Use label else node name */
+ lpg->cdev.name = of_get_property(np, "label", NULL) ? : np->name;
+ lpg->cdev.default_trigger = of_get_property(np, "linux,default-trigger", NULL);
+ lpg->cdev.brightness_set = lpg_brightness_set;
+ lpg->cdev.brightness_get = lpg_brightness_get;
+ lpg->cdev.blink_set = lpg_blink_set;
+ lpg->cdev.pattern_set = lpg_pattern_set;
+ lpg->cdev.pattern_clear = lpg_pattern_clear;
+ lpg->cdev.pattern_get = lpg_pattern_get;
+ lpg->cdev.max_brightness = 255;
+
+ if (!of_property_read_string(np, "default-state", &state) &&
+ !strcmp(state, "on"))
+ lpg->cdev.brightness = LED_FULL;
+ else
+ lpg->cdev.brightness = LED_OFF;
+
+ lpg_brightness_set(&lpg->cdev, lpg->cdev.brightness);
+
+ ret = devm_led_classdev_register(lpg->dev, &lpg->cdev);
+ if (ret)
+ dev_err(lpg->dev, "unable to register \"%s\"\n", lpg->cdev.name);
+
+ return ret;
+}
+
+static int lpg_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct lpg *lpg;
+ u32 dtest[2];
+ int ret;
+
+ lpg = devm_kzalloc(&pdev->dev, sizeof(*lpg), GFP_KERNEL);
+ if (!lpg)
+ return -ENOMEM;
+
+ lpg->dev = &pdev->dev;
+
+ lpg->map = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!lpg->map) {
+ dev_err(&pdev->dev, "parent regmap unavailable\n");
+ return -ENXIO;
+ }
+
+ ret = of_property_read_u32(np, "reg", &lpg->reg);
+ if (ret) {
+ dev_err(&pdev->dev, "no register offset specified\n");
+ return -EINVAL;
+ }
+
+ if (!of_find_property(np, "#pwm-cells", NULL))
+ lpg->is_lpg = true;
+
+ lpg->tri_led = qcom_tri_led_get(&pdev->dev);
+ if (IS_ERR(lpg->tri_led))
+ return PTR_ERR(lpg->tri_led);
+
+ ret = of_property_read_u32_array(np, "qcom,dtest", dtest, 2);
+ if (!ret) {
+ lpg->dtest_line = dtest[0];
+ lpg->dtest_value = dtest[1];
+ }
+
+ if (lpg->is_lpg) {
+ ret = lpg_register_led(lpg);
+ if (ret)
+ return ret;
+ } else {
+ ret = lpg_register_pwm(lpg);
+ if (ret)
+ return ret;
+ }
+
+ lpg_apply_dtest(lpg);
+
+ platform_set_drvdata(pdev, lpg);
+
+ return 0;
+}
+
+static int lpg_remove(struct platform_device *pdev)
+{
+ struct lpg *lpg = platform_get_drvdata(pdev);
+
+ if (!lpg->is_lpg)
+ pwmchip_remove(&lpg->chip);
+
+ qcom_lpg_lut_free(lpg->pattern);
+
+ return 0;
+}
+
+static const struct of_device_id lpg_of_table[] = {
+ { .compatible = "qcom,spmi-lpg" },
+ {},
+};
+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 TRI LED driver");
+MODULE_LICENSE("GPL v2");
new file mode 100644
@@ -0,0 +1,30 @@
+#ifndef __LEDS_QCOM_LPG_H__
+#define __LEDS_QCOM_LPG_H__
+
+struct qcom_tri_led;
+struct qcom_lpg_lut;
+
+/*
+ * qcom_lpg_pattern - object tracking allocated LUT entries
+ * @lut: reference to the client & LUT device context
+ * @lo_idx: index of first entry in the LUT used by pattern
+ * @hi_idx: index of the last entry in the LUT used by pattern
+ */
+struct qcom_lpg_pattern {
+ struct qcom_lpg_lut *lut;
+
+ unsigned int lo_idx;
+ unsigned int hi_idx;
+};
+
+struct qcom_tri_led *qcom_tri_led_get(struct device *dev);
+int qcom_tri_led_set(struct qcom_tri_led *tri, bool enabled);
+
+struct qcom_lpg_lut *qcom_lpg_lut_get(struct device *dev);
+struct qcom_lpg_pattern *qcom_lpg_lut_store(struct qcom_lpg_lut *lut,
+ const u16 *values, size_t len);
+u16 *qcom_lpg_lut_read(struct qcom_lpg_pattern *pattern, size_t *len);
+void qcom_lpg_lut_free(struct qcom_lpg_pattern *pattern);
+int qcom_lpg_lut_sync(struct qcom_lpg_lut *lut);
+
+#endif
new file mode 100644
@@ -0,0 +1,193 @@
+/* Copyright (c) 2017 Linaro Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "leds-qcom-lpg.h"
+
+#define TRI_LED_SRC_SEL 0x45
+#define TRI_LED_EN_CTL 0x46
+#define TRI_LED_ATC_CTL 0x47
+
+#define TRI_LED_COUNT 3
+
+static struct platform_driver tri_led_driver;
+
+/*
+ * tri_led_dev - TRILED device context
+ * @dev: struct device reference
+ * @map: regmap for register access
+ * @reg: base address of TRILED block
+ */
+struct tri_led_dev {
+ struct device *dev;
+ struct regmap *map;
+
+ u32 reg;
+};
+
+/*
+ * qcom_tri_led - representation of a single color
+ * @tdev: TRILED device reference
+ * @color: color of this object 0 <= color < 3
+ */
+struct qcom_tri_led {
+ struct tri_led_dev *tdev;
+ u8 color;
+};
+
+static void tri_led_release(struct device *dev, void *res)
+{
+ struct qcom_tri_led *tri = res;
+ struct tri_led_dev *tdev = tri->tdev;
+
+ put_device(tdev->dev);
+}
+
+/**
+ * qcom_tri_led_get() - acquire a reference to a single color of the TRILED
+ * @dev: struct device of the client
+ *
+ * Returned devres allocated TRILED color object, NULL if client lacks TRILED
+ * reference or ERR_PTR on failure.
+ */
+struct qcom_tri_led *qcom_tri_led_get(struct device *dev)
+{
+ struct platform_device *pdev;
+ struct of_phandle_args args;
+ struct qcom_tri_led *tri;
+ int ret;
+
+ ret = of_parse_phandle_with_fixed_args(dev->of_node,
+ "qcom,tri-led", 1, 0, &args);
+ if (ret)
+ return NULL;
+
+ pdev = of_find_device_by_node(args.np);
+ of_node_put(args.np);
+ if (!pdev || !pdev->dev.driver)
+ return ERR_PTR(-EPROBE_DEFER);
+
+ if (pdev->dev.driver != &tri_led_driver.driver) {
+ dev_err(dev, "referenced node is not a tri-led\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ if (args.args[0] >= TRI_LED_COUNT) {
+ dev_err(dev, "invalid color\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ tri = devres_alloc(tri_led_release, sizeof(*tri), GFP_KERNEL);
+ if (!tri)
+ return ERR_PTR(-ENOMEM);
+
+ tri->tdev = platform_get_drvdata(pdev);
+ tri->color = args.args[0];
+
+ devres_add(dev, tri);
+
+ return tri;
+}
+EXPORT_SYMBOL_GPL(qcom_tri_led_get);
+
+/**
+ * qcom_tri_led_set() - enable/disable a TRILED output
+ * @tri: TRILED color object reference
+ * @enable: new state of the output
+ *
+ * Returns 0 on success, negative errno on failure.
+ */
+int qcom_tri_led_set(struct qcom_tri_led *tri, bool enable)
+{
+ struct tri_led_dev *tdev = tri->tdev;
+ unsigned int mask;
+ unsigned int val;
+
+ /* red, green, blue are mapped to bits 7, 6 and 5 respectively */
+ mask = BIT(7 - tri->color);
+ val = enable ? mask : 0;
+
+ return regmap_update_bits(tdev->map, tdev->reg + TRI_LED_EN_CTL,
+ mask, val);
+}
+EXPORT_SYMBOL_GPL(qcom_tri_led_set);
+
+static int tri_led_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct tri_led_dev *tri;
+ u32 src_sel;
+ int ret;
+
+ tri = devm_kzalloc(&pdev->dev, sizeof(*tri), GFP_KERNEL);
+ if (!tri)
+ return -ENOMEM;
+
+ tri->dev = &pdev->dev;
+
+ tri->map = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!tri->map) {
+ dev_err(&pdev->dev, "parent regmap unavailable\n");
+ return -ENXIO;
+ }
+
+ ret = of_property_read_u32(np, "reg", &tri->reg);
+ if (ret) {
+ dev_err(&pdev->dev, "no register offset specified\n");
+ return -EINVAL;
+ }
+
+ ret = of_property_read_u32(np, "qcom,power-source", &src_sel);
+ if (ret || src_sel == 2 || src_sel > 3) {
+ dev_err(&pdev->dev, "invalid power source\n");
+ return -EINVAL;
+ }
+
+ /* Disable automatic trickle charge LED */
+ regmap_write(tri->map, tri->reg + TRI_LED_ATC_CTL, 0);
+
+ /* Configure power source */
+ regmap_write(tri->map, tri->reg + TRI_LED_SRC_SEL, src_sel);
+
+ /* Default all outputs to off */
+ regmap_write(tri->map, tri->reg + TRI_LED_EN_CTL, 0);
+
+ platform_set_drvdata(pdev, tri);
+
+ return 0;
+}
+
+static const struct of_device_id tri_led_of_table[] = {
+ { .compatible = "qcom,spmi-tri-led" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, tri_led_of_table);
+
+static struct platform_driver tri_led_driver = {
+ .probe = tri_led_probe,
+ .driver = {
+ .name = "qcom_tri_led",
+ .of_match_table = tri_led_of_table,
+ },
+};
+module_platform_driver(tri_led_driver);
+
+MODULE_DESCRIPTION("Qualcomm TRI LED driver");
+MODULE_LICENSE("GPL v2");
The Light Pulse Generator (LPG) is a PWM-block found in a wide range of PMICs from Qualcomm. It can operate on fixed parameters or based on a lookup-table, altering the duty cycle over time - which provides the means for e.g. hardware assisted transitions of LED brightness. Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> --- Changes since v1: - Remove custom DT properties for patterns - Extract pattern interface into the LED core drivers/leds/Kconfig | 7 + drivers/leds/Makefile | 3 + drivers/leds/leds-qcom-lpg-lut.c | 296 +++++++++++++++ drivers/leds/leds-qcom-lpg.c | 782 +++++++++++++++++++++++++++++++++++++++ drivers/leds/leds-qcom-lpg.h | 30 ++ drivers/leds/leds-qcom-triled.c | 193 ++++++++++ 6 files changed, 1311 insertions(+) create mode 100644 drivers/leds/leds-qcom-lpg-lut.c create mode 100644 drivers/leds/leds-qcom-lpg.c create mode 100644 drivers/leds/leds-qcom-lpg.h create mode 100644 drivers/leds/leds-qcom-triled.c -- 2.12.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html