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From: Christian Marangi <ansuelsmth@gmail.com>
To: Pavel Machek <pavel@ucw.cz>, Lee Jones <lee@kernel.org>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Jacek Anaszewski <jacek.anaszewski@gmail.com>,
	linux-leds@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org
Cc: Christian Marangi <ansuelsmth@gmail.com>
Subject: [PATCH 3/3] leds: leds-lp5569: Add support for Texas Instruments LP5569
Date: Wed, 15 May 2024 16:31:28 +0200	[thread overview]
Message-ID: <20240515143129.31557-3-ansuelsmth@gmail.com> (raw)
In-Reply-To: <20240515143129.31557-1-ansuelsmth@gmail.com>

Add support for Texas Instruments LP5569 LED driver.

Texas Instruments LP5569 is 9 channels chip with programmable engines.

It almost a copy of LP5523 with fundamental changes to regs order and
regs content.

Has difference in how the clock is handled and doesn't support detecting
clock time automatically, different handling for selftest and different
sheme for the status regs.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/leds/Kconfig       |   16 +-
 drivers/leds/Makefile      |    1 +
 drivers/leds/leds-lp5569.c | 1145 ++++++++++++++++++++++++++++++++++++
 3 files changed, 1159 insertions(+), 3 deletions(-)
 create mode 100644 drivers/leds/leds-lp5569.c

diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 05e6af88b88c..b1d7d94317b3 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -414,7 +414,7 @@ config LEDS_LP50XX
 	  module will be called leds-lp50xx.
 
 config LEDS_LP55XX_COMMON
-	tristate "Common Driver for TI/National LP5521/5523/55231/5562/8501"
+	tristate "Common Driver for TI/National LP5521/5523/55231/5562/5569/8501"
 	depends on LEDS_CLASS
 	depends on LEDS_CLASS_MULTICOLOR
 	depends on OF
@@ -422,8 +422,8 @@ config LEDS_LP55XX_COMMON
 	select FW_LOADER
 	select FW_LOADER_USER_HELPER
 	help
-	  This option supports common operations for LP5521/5523/55231/5562/8501
-	  devices.
+	  This option supports common operations for LP5521/5523/55231/5562/5569/
+	  8501 devices.
 
 config LEDS_LP5521
 	tristate "LED Support for N.S. LP5521 LED driver chip"
@@ -456,6 +456,16 @@ config LEDS_LP5562
 	  Driver provides direct control via LED class and interface for
 	  programming the engines.
 
+config LEDS_LP5569
+	tristate "LED Support for TI LP5569 LED driver chip"
+	depends on LEDS_CLASS && I2C
+	depends on LEDS_LP55XX_COMMON
+	help
+	  If you say yes here you get support for TI LP5569 LED driver.
+	  It is 9 channels chip with programmable engines.
+	  Driver provides direct control via LED class and interface for
+	  programming the engines.
+
 config LEDS_LP8501
 	tristate "LED Support for TI LP8501 LED driver chip"
 	depends on LEDS_CLASS && I2C
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index effdfc6f1e95..ad21941efa19 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_LEDS_LP50XX)		+= leds-lp50xx.o
 obj-$(CONFIG_LEDS_LP5521)		+= leds-lp5521.o
 obj-$(CONFIG_LEDS_LP5523)		+= leds-lp5523.o
 obj-$(CONFIG_LEDS_LP5562)		+= leds-lp5562.o
+obj-$(CONFIG_LEDS_LP5569)		+= leds-lp5569.o
 obj-$(CONFIG_LEDS_LP55XX_COMMON)	+= leds-lp55xx-common.o
 obj-$(CONFIG_LEDS_LP8501)		+= leds-lp8501.o
 obj-$(CONFIG_LEDS_LP8788)		+= leds-lp8788.o
diff --git a/drivers/leds/leds-lp5569.c b/drivers/leds/leds-lp5569.c
new file mode 100644
index 000000000000..4a8c08ebe685
--- /dev/null
+++ b/drivers/leds/leds-lp5569.c
@@ -0,0 +1,1145 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * lp5569.c - LP5569LED Driver
+ *
+ * Copyright (C) 2010 Nokia Corporation
+ * Copyright (C) 2012 Texas Instruments
+ *
+ * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
+ *          Milo(Woogyom) Kim <milo.kim@ti.com>
+ *          Christian Marangi <ansuelsmth@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/i2c.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/platform_data/leds-lp55xx.h>
+#include <linux/slab.h>
+#include <dt-bindings/leds/leds-lp55xx.h>
+
+#include "leds-lp55xx-common.h"
+
+/* Registers */
+#define LP5569_REG_ENABLE		0x00
+#define   LP5569_ENABLE			BIT(6)
+
+#define LP5569_REG_EXEC_CTRL		0x01
+/*
+ * Program Memory Operations
+ * Same Mask for each engine for both mode and exec
+ * ENG1	GENMASK(3, 2)
+ * ENG2	GENMASK(5, 4)
+ * ENG3	GENMASK(7, 6)
+ */
+#define LP5569_MODE_ENG_MASK		GENMASK(1, 0)
+#define   LP5569_MODE_ENG_SHIFT		2
+#define   LP5569_MODE_DISABLE_ENG	FIELD_PREP_CONST(LP5569_MODE_ENG_MASK, 0x0)
+#define   LP5569_MODE_LOAD_ENG		FIELD_PREP_CONST(LP5569_MODE_ENG_MASK, 0x1)
+#define   LP5569_MODE_RUN_ENG		FIELD_PREP_CONST(LP5569_MODE_ENG_MASK, 0x2)
+#define   LP5569_MODE_HALT_ENG		FIELD_PREP_CONST(LP5569_MODE_ENG_MASK, 0x3)
+
+#define   LP5569_MODE_ENGn_SHIFT(n)	(LP5569_MODE_ENG_SHIFT + (2 * (3 - (n))))
+#define   LP5569_MODE_ENGn_MASK(n)	(LP5569_MODE_ENG_MASK << LP5569_MODE_ENGn_SHIFT(n))
+#define   LP5569_MODE_ENGn_GET(n, mode)	\
+	(((mode) >> LP5569_MODE_ENGn_SHIFT(n)) & LP5569_MODE_ENG_MASK)
+
+#define LP5569_REG_OP_MODE		0x02
+#define   LP5569_EXEC_ENG_MASK		GENMASK(1, 0)
+#define   LP5569_EXEC_ENG_SHIFT		2
+#define   LP5569_EXEC_HOLD_ENG		FIELD_PREP_CONST(LP5569_EXEC_ENG_MASK, 0x0)
+#define   LP5569_EXEC_STEP_ENG		FIELD_PREP_CONST(LP5569_EXEC_ENG_MASK, 0x1)
+#define   LP5569_EXEC_RUN_ENG		FIELD_PREP_CONST(LP5569_EXEC_ENG_MASK, 0x2)
+#define   LP5569_EXEC_ONCE_ENG		FIELD_PREP_CONST(LP5569_EXEC_ENG_MASK, 0x3)
+
+#define   LP5569_EXEC_ENGn_SHIFT(n)	(LP5569_EXEC_ENG_SHIFT + (2 * (3 - (n))))
+#define   LP5569_EXEC_ENGn_MASK(n)	(LP5569_EXEC_ENG_MASK << LP5569_EXEC_ENGn_SHIFT(n))
+
+#define LP5569_REG_ENABLE_LEDS_MSB	0x04
+#define LP5569_REG_ENABLE_LEDS_LSB	0x05
+#define LP5569_REG_LED_CTRL_BASE	0x07
+#define   LP5569_FADER_MAPPING_MASK	GENMASK(7, 5)
+#define LP5569_REG_LED_PWM_BASE		0x16
+#define LP5569_REG_LED_CURRENT_BASE	0x22
+#define LP5569_REG_MISC			0x2F
+#define   LP5569_AUTO_INC		BIT(6)
+#define   LP5569_PWR_SAVE		BIT(5)
+#define   LP5569_CP_MODE_MASK		GENMASK(4, 3)
+#define   LP5569_PWM_PWR_SAVE		BIT(2)
+#define   LP5569_INTERNAL_CLK		BIT(0)
+#define LP5569_REG_MISC2		0x33
+#define   LP5569_LED_SHORT_TEST		BIT(4)
+#define   LP5569_LED_OPEN_TEST		BIT(3)
+#define LP5569_REG_STATUS		0x3C
+#define   LP5569_MASK_BUSY		BIT(7)
+#define   LP5569_STARTUP_BUSY		BIT(6)
+#define   LP5569_ENGINE_BUSY		BIT(5)
+#define   LP5569_ENGINE1_INT		BIT(2)
+#define   LP5569_ENGINE2_INT		BIT(1)
+#define   LP5569_ENGINE3_INT		BIT(0)
+#define   LP5569_ENG_STATUS_MASK	(LP5569_ENGINE1_INT | LP5569_ENGINE2_INT | \
+					 LP5569_ENGINE3_INT)
+#define LP5569_REG_IO_CONTROL		0x3D
+#define   LP5569_CLK_OUTPUT		BIT(3)
+#define LP5569_REG_RESET		0x3F
+#define   LP5569_RESET			0xFF
+#define LP5569_REG_MASTER_FADER_BASE	0x46
+#define LP5569_REG_CH1_PROG_START	0x4B
+#define LP5569_REG_CH2_PROG_START	0x4C
+#define LP5569_REG_CH3_PROG_START	0x4D
+#define LP5569_REG_PROG_PAGE_SEL	0x4F
+#define LP5569_REG_PROG_MEM		0x50
+#define LP5569_REG_LED_FAULT1		0x81
+#define   LP5569_LED_FAULT8		BIT(0)
+#define LP5569_REG_LED_FAULT2		0x82
+#define   LP5569_LED_FAULT7		BIT(7)
+#define   LP5569_LED_FAULT6		BIT(6)
+#define   LP5569_LED_FAULT5		BIT(5)
+#define   LP5569_LED_FAULT4		BIT(4)
+#define   LP5569_LED_FAULT3		BIT(3)
+#define   LP5569_LED_FAULT2		BIT(2)
+#define   LP5569_LED_FAULT1		BIT(1)
+#define   LP5569_LED_FAULT0		BIT(0)
+
+#define LP5569_MAX_LEDS			9
+
+#define LP5569_PROGRAM_PAGES		16
+#define LP5569_PROGRAM_LENGTH		32	/* bytes */
+/* Memory is used like this:
+ * 0x00 engine 1 program
+ * 0x10 engine 2 program
+ * 0x20 engine 3 program
+ * 0x30 engine 1 muxing info
+ * 0x40 engine 2 muxing info
+ * 0x50 engine 3 muxing info
+ */
+#define LP5569_ENG1_PROG_ADDR		0x0
+#define LP5569_ENG2_PROG_ADDR		0x10
+#define LP5569_ENG3_PROG_ADDR		0x20
+#define LP5569_ENG1_MUX_ADDR		0x30
+#define LP5569_ENG2_MUX_ADDR		0x40
+#define LP5569_ENG3_MUX_ADDR		0x50
+
+/* Memory Page Selection */
+#define LP5569_PAGE_ENG_OFFSET		0
+#define LP5569_PAGE_ENG(n)		(((n) - 1) + LP5569_PAGE_ENG_OFFSET)
+#define LP5569_PAGE_MUX_OFFSET		3
+#define LP5569_PAGE_MUX(n)		(((n) - 1) + LP5569_PAGE_MUX_OFFSET)
+
+#define LEDn_STATUS_FAULT(n, status)	((status) >> (n) & BIT(0))
+#define LED_ACTIVE(mux, led)		(!!((mux) & (0x0001 << (led))))
+
+#define LP5569_DEFAULT_CONFIG \
+	(LP5569_AUTO_INC | LP5569_PWR_SAVE | LP5569_PWM_PWR_SAVE)
+
+enum lp5569_chip_id {
+	LP5569,
+};
+
+static int lp5569_init_program_engine(struct lp55xx_chip *chip);
+
+static inline void lp5569_wait_opmode_done(void)
+{
+	usleep_range(1000, 2000);
+}
+
+static void lp5569_set_led_current(struct lp55xx_led *led, u8 led_current)
+{
+	led->led_current = led_current;
+	lp55xx_write(led->chip, LP5569_REG_LED_CURRENT_BASE + led->chan_nr,
+		     led_current);
+}
+
+static int lp5569_post_init_device(struct lp55xx_chip *chip)
+{
+	int ret;
+	int val;
+
+	ret = lp55xx_write(chip, LP5569_REG_ENABLE, LP5569_ENABLE);
+	if (ret)
+		return ret;
+
+	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
+	usleep_range(1000, 2000);
+
+	val = LP5569_DEFAULT_CONFIG;
+	val |= FIELD_PREP(LP5569_CP_MODE_MASK, chip->pdata->charge_pump_mode);
+
+	if (chip->pdata->clock_mode == LP55XX_CLOCK_INT)
+		val |= LP5569_INTERNAL_CLK;
+
+	ret = lp55xx_write(chip, LP5569_REG_MISC, val);
+	if (ret)
+		return ret;
+
+	if (chip->pdata->clock_mode == LP55XX_CLOCK_INT) {
+		ret = lp55xx_update_bits(chip, LP5569_REG_IO_CONTROL,
+					 LP5569_CLK_OUTPUT,
+					 LP5569_CLK_OUTPUT);
+		if (ret)
+			return ret;
+	}
+
+	return lp5569_init_program_engine(chip);
+}
+
+static void lp5569_load_engine(struct lp55xx_chip *chip)
+{
+	enum lp55xx_engine_index idx = chip->engine_idx;
+	u8 mask, val;
+
+	mask = LP5569_MODE_ENGn_MASK(idx);
+	val = LP5569_MODE_LOAD_ENG << LP5569_MODE_ENGn_SHIFT(idx);
+
+	lp55xx_update_bits(chip, LP5569_REG_OP_MODE, mask, val);
+
+	lp5569_wait_opmode_done();
+}
+
+static void lp5569_load_engine_and_select_page(struct lp55xx_chip *chip)
+{
+	enum lp55xx_engine_index idx = chip->engine_idx;
+
+	lp5569_load_engine(chip);
+
+	lp55xx_write(chip, LP5569_REG_PROG_PAGE_SEL, LP5569_PAGE_ENG(idx));
+}
+
+static void lp5569_stop_all_engines(struct lp55xx_chip *chip)
+{
+	lp55xx_write(chip, LP5569_REG_OP_MODE, 0);
+	lp5569_wait_opmode_done();
+}
+
+static void lp5569_stop_engine(struct lp55xx_chip *chip)
+{
+	enum lp55xx_engine_index idx = chip->engine_idx;
+
+	lp55xx_update_bits(chip, LP5569_REG_OP_MODE, LP5569_MODE_ENGn_MASK(idx), 0);
+
+	lp5569_wait_opmode_done();
+}
+
+static void lp5569_turn_off_channels(struct lp55xx_chip *chip)
+{
+	int i;
+
+	for (i = 0; i < LP5569_MAX_LEDS; i++)
+		lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + i, 0);
+}
+
+static void lp5569_run_engine(struct lp55xx_chip *chip, bool start)
+{
+	int i, ret;
+	u8 mode;
+	u8 exec;
+
+	/* stop engine */
+	if (!start) {
+		lp5569_stop_engine(chip);
+		lp5569_turn_off_channels(chip);
+		return;
+	}
+
+	/*
+	 * To run the engine,
+	 * operation mode and enable register should updated at the same time
+	 */
+
+	ret = lp55xx_read(chip, LP5569_REG_OP_MODE, &mode);
+	if (ret)
+		return;
+
+	ret = lp55xx_read(chip, LP5569_REG_EXEC_CTRL, &exec);
+	if (ret)
+		return;
+
+	/* change operation mode to RUN only when each engine is loading */
+	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
+		if (LP5569_MODE_ENGn_GET(i, mode) != LP5569_MODE_LOAD_ENG)
+			continue;
+
+		mode &= ~LP5569_MODE_ENGn_MASK(i);
+		mode |= LP5569_MODE_RUN_ENG << LP5569_MODE_ENGn_SHIFT(i);
+		exec &= ~LP5569_EXEC_ENGn_MASK(i);
+		exec |= LP5569_EXEC_RUN_ENG << LP5569_EXEC_ENGn_SHIFT(i);
+	}
+
+	lp55xx_write(chip, LP5569_REG_OP_MODE, mode);
+	lp5569_wait_opmode_done();
+
+	lp55xx_write(chip, LP5569_REG_EXEC_CTRL, exec);
+}
+
+static int lp5569_init_program_engine(struct lp55xx_chip *chip)
+{
+	int i;
+	int j;
+	int ret;
+	u8 status;
+	/* one pattern per engine setting LED MUX start and stop addresses */
+	static const u8 pattern[][LP5569_PROGRAM_LENGTH] =  {
+		{ 0x9c, LP5569_ENG1_MUX_ADDR, 0x9c, 0xb0, 0x9d, 0x80, 0xd8, 0x00, 0},
+		{ 0x9c, LP5569_ENG2_MUX_ADDR, 0x9c, 0xc0, 0x9d, 0x80, 0xd8, 0x00, 0},
+		{ 0x9c, LP5569_ENG3_MUX_ADDR, 0x9c, 0xd0, 0x9d, 0x80, 0xd8, 0x00, 0},
+	};
+
+	/* hardcode 32 bytes of memory for each engine from program memory */
+	ret = lp55xx_write(chip, LP5569_REG_CH1_PROG_START, LP5569_ENG1_PROG_ADDR);
+	if (ret)
+		return ret;
+
+	ret = lp55xx_write(chip, LP5569_REG_CH2_PROG_START, LP5569_ENG2_PROG_ADDR);
+	if (ret)
+		return ret;
+
+	ret = lp55xx_write(chip, LP5569_REG_CH3_PROG_START, LP5569_ENG3_PROG_ADDR);
+	if (ret)
+		return ret;
+
+	/* write LED MUX address space for each engine */
+	for (i = LP55XX_ENGINE_1; i <= LP55XX_ENGINE_3; i++) {
+		chip->engine_idx = i;
+		lp5569_load_engine_and_select_page(chip);
+
+		for (j = 0; j < LP5569_PROGRAM_LENGTH; j++) {
+			ret = lp55xx_write(chip, LP5569_REG_PROG_MEM + j,
+					   pattern[i - 1][j]);
+			if (ret)
+				goto out;
+		}
+	}
+
+	lp5569_run_engine(chip, true);
+
+	/* Let the programs run for couple of ms and check the engine status */
+	usleep_range(3000, 6000);
+	lp55xx_read(chip, LP5569_REG_STATUS, &status);
+	status = FIELD_GET(LP5569_ENG_STATUS_MASK, status);
+
+	if (status != LP5569_ENG_STATUS_MASK) {
+		dev_err(&chip->cl->dev,
+			"could not configure LED engine, status = 0x%.2x\n",
+			status);
+		ret = -1;
+	}
+
+out:
+	lp5569_stop_all_engines(chip);
+	return ret;
+}
+
+static int lp5569_update_program_memory(struct lp55xx_chip *chip,
+					const u8 *data, size_t size)
+{
+	u8 pattern[LP5569_PROGRAM_LENGTH] = {0};
+	unsigned int cmd;
+	char c[3];
+	int nrchars;
+	int ret;
+	int offset = 0;
+	int i = 0;
+
+	while ((offset < size - 1) && (i < LP5569_PROGRAM_LENGTH)) {
+		/* separate sscanfs because length is working only for %s */
+		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
+		if (ret != 1)
+			goto err;
+
+		ret = sscanf(c, "%2x", &cmd);
+		if (ret != 1)
+			goto err;
+
+		pattern[i] = (u8)cmd;
+		offset += nrchars;
+		i++;
+	}
+
+	/* Each instruction is 16bit long. Check that length is even */
+	if (i % 2)
+		goto err;
+
+	for (i = 0; i < LP5569_PROGRAM_LENGTH; i++) {
+		ret = lp55xx_write(chip, LP5569_REG_PROG_MEM + i, pattern[i]);
+		if (ret)
+			return -EINVAL;
+	}
+
+	return size;
+
+err:
+	dev_err(&chip->cl->dev, "wrong pattern format\n");
+	return -EINVAL;
+}
+
+static void lp5569_firmware_loaded(struct lp55xx_chip *chip)
+{
+	const struct firmware *fw = chip->fw;
+
+	if (fw->size > (LP5569_PROGRAM_LENGTH * LP5569_PROGRAM_PAGES * 2)) {
+		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
+			fw->size);
+		return;
+	}
+
+	/*
+	 * Program memory sequence
+	 *  1) set engine mode to "LOAD"
+	 *  2) write firmware data into program memory
+	 */
+
+	lp5569_load_engine_and_select_page(chip);
+	lp5569_update_program_memory(chip, fw->data, fw->size);
+}
+
+static ssize_t show_engine_mode(struct device *dev,
+				struct device_attribute *attr,
+				char *buf, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
+
+	switch (mode) {
+	case LP55XX_ENGINE_RUN:
+		return sprintf(buf, "run\n");
+	case LP55XX_ENGINE_LOAD:
+		return sprintf(buf, "load\n");
+	case LP55XX_ENGINE_DISABLED:
+	default:
+		return sprintf(buf, "disabled\n");
+	}
+}
+show_mode(1)
+show_mode(2)
+show_mode(3)
+
+static ssize_t store_engine_mode(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t len, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	struct lp55xx_engine *engine = &chip->engines[nr - 1];
+
+	mutex_lock(&chip->lock);
+
+	chip->engine_idx = nr;
+
+	if (!strncmp(buf, "run", 3)) {
+		lp5569_run_engine(chip, true);
+		engine->mode = LP55XX_ENGINE_RUN;
+	} else if (!strncmp(buf, "load", 4)) {
+		lp5569_stop_engine(chip);
+		lp5569_load_engine(chip);
+		engine->mode = LP55XX_ENGINE_LOAD;
+	} else if (!strncmp(buf, "disabled", 8)) {
+		lp5569_stop_engine(chip);
+		engine->mode = LP55XX_ENGINE_DISABLED;
+	}
+
+	mutex_unlock(&chip->lock);
+
+	return len;
+}
+store_mode(1)
+store_mode(2)
+store_mode(3)
+
+static int lp5569_mux_parse(const char *buf, u16 *mux, size_t len)
+{
+	u16 tmp_mux = 0;
+	int i;
+
+	len = min_t(int, len, LP5569_MAX_LEDS);
+
+	for (i = 0; i < len; i++) {
+		switch (buf[i]) {
+		case '1':
+			tmp_mux |= (1 << i);
+			break;
+		case '0':
+			break;
+		case '\n':
+			i = len;
+			break;
+		default:
+			return -1;
+		}
+	}
+	*mux = tmp_mux;
+
+	return 0;
+}
+
+static void lp5569_mux_to_array(u16 led_mux, char *array)
+{
+	int i, pos = 0;
+
+	for (i = 0; i < LP5569_MAX_LEDS; i++)
+		pos += sprintf(array + pos, "%x", LED_ACTIVE(led_mux, i));
+
+	array[pos] = '\0';
+}
+
+static ssize_t show_engine_leds(struct device *dev,
+				struct device_attribute *attr,
+				char *buf, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	char mux[LP5569_MAX_LEDS + 1];
+
+	lp5569_mux_to_array(chip->engines[nr - 1].led_mux, mux);
+
+	return sprintf(buf, "%s\n", mux);
+}
+show_leds(1)
+show_leds(2)
+show_leds(3)
+
+static int lp5569_load_mux(struct lp55xx_chip *chip, u16 mux, int nr)
+{
+	struct lp55xx_engine *engine = &chip->engines[nr - 1];
+	int ret;
+
+	lp5569_load_engine(chip);
+
+	ret = lp55xx_write(chip, LP5569_REG_PROG_PAGE_SEL, LP5569_PAGE_MUX(nr));
+	if (ret)
+		return ret;
+
+	ret = lp55xx_write(chip, LP5569_REG_PROG_MEM, (u8)(mux >> 8));
+	if (ret)
+		return ret;
+
+	ret = lp55xx_write(chip, LP5569_REG_PROG_MEM + 1, (u8)(mux));
+	if (ret)
+		return ret;
+
+	engine->led_mux = mux;
+	return 0;
+}
+
+static ssize_t store_engine_leds(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t len, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	struct lp55xx_engine *engine = &chip->engines[nr - 1];
+	u16 mux = 0;
+	ssize_t ret;
+
+	if (lp5569_mux_parse(buf, &mux, len))
+		return -EINVAL;
+
+	mutex_lock(&chip->lock);
+
+	chip->engine_idx = nr;
+	ret = -EINVAL;
+
+	if (engine->mode != LP55XX_ENGINE_LOAD)
+		goto leave;
+
+	if (lp5569_load_mux(chip, mux, nr))
+		goto leave;
+
+	ret = len;
+leave:
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+store_leds(1)
+store_leds(2)
+store_leds(3)
+
+static ssize_t store_engine_load(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t len, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	int ret;
+
+	mutex_lock(&chip->lock);
+
+	chip->engine_idx = nr;
+	lp5569_load_engine_and_select_page(chip);
+	ret = lp5569_update_program_memory(chip, buf, len);
+
+	mutex_unlock(&chip->lock);
+
+	return ret;
+}
+store_load(1)
+store_load(2)
+store_load(3)
+
+static ssize_t lp5569_led_open_test(struct lp55xx_led *led, char *buf)
+{
+	struct lp55xx_chip *chip = led->chip;
+	struct lp55xx_platform_data *pdata = chip->pdata;
+	bool leds_fault[LP5569_MAX_LEDS];
+	struct lp55xx_led *led_tmp = led;
+	int i, ret, pos = 0;
+	u8 status;
+
+	/* Set in STANDBY state */
+	ret = lp55xx_write(chip, LP5569_REG_ENABLE, 0);
+	if (ret)
+		goto exit;
+
+	/* Wait 1ms for device to enter STANDBY state */
+	usleep_range(1000, 2000);
+
+	/* Set Charge Pump to 1.5x */
+	ret = lp55xx_update_bits(chip, LP5569_REG_MISC,
+				 FIELD_PREP(LP5569_CP_MODE_MASK, LP55XX_CP_BOOST),
+				 LP5569_CP_MODE_MASK);
+	if (ret)
+		goto exit;
+
+	/* Enable LED Open Test */
+	ret = lp55xx_update_bits(chip, LP5569_REG_MISC2, LP5569_LED_OPEN_TEST,
+				 LP5569_LED_OPEN_TEST);
+	if (ret)
+		goto exit;
+
+	/* Put Device in NORMAL state */
+	ret = lp55xx_write(chip, LP5569_REG_ENABLE, LP5569_ENABLE);
+	if (ret)
+		goto exit;
+
+	/* Wait 500 us for device to enter NORMAL state */
+	usleep_range(500, 750);
+
+	/* Enable LED and set to 100% brightness */
+	for (i = 0; i < pdata->num_channels; i++) {
+		ret = lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + led_tmp->chan_nr,
+				   LED_FULL);
+		if (ret)
+			goto exit;
+
+		led_tmp++;
+	}
+
+	/* Wait 500 us for device to fill status regs */
+	usleep_range(500, 750);
+
+	/* Parse status led fault 1 regs */
+	ret = lp55xx_read(chip, LP5569_REG_LED_FAULT1, &status);
+	if (ret < 0)
+		goto exit;
+
+	for (i = 0; i < 8; i++)
+		leds_fault[i] = !!((status >> i) & 0x1);
+
+	/* Parse status led fault 2 regs */
+	ret = lp55xx_read(chip, LP5569_REG_LED_FAULT2, &status);
+	if (ret < 0)
+		goto exit;
+
+	for (i = 0; i < 1; i++)
+		leds_fault[i + 8] = !!((status >> i) & 0x1);
+
+	/* Report LED fault */
+	led_tmp = led;
+	for (i = 0; i < pdata->num_channels; i++) {
+		if (leds_fault[led_tmp->chan_nr])
+			pos += sprintf(buf + pos, "LED %d OPEN FAIL\n",
+				       led_tmp->chan_nr);
+
+		led_tmp++;
+	}
+
+	ret = pos;
+
+exit:
+	/* Disable LED Open Test */
+	lp55xx_update_bits(chip, LP5569_REG_MISC2, LP5569_LED_OPEN_TEST,
+			   0);
+
+	led_tmp = led;
+	for (i = 0; i < pdata->num_channels; i++) {
+		lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + led_tmp->chan_nr,
+			     0);
+
+		led_tmp++;
+	}
+
+	return ret;
+}
+
+static ssize_t lp5569_led_short_test(struct lp55xx_led *led, char *buf)
+{
+	struct lp55xx_chip *chip = led->chip;
+	struct lp55xx_platform_data *pdata = chip->pdata;
+	bool leds_fault[LP5569_MAX_LEDS];
+	struct lp55xx_led *led_tmp = led;
+	int i, ret, pos = 0;
+	u8 status;
+
+	/* Set in STANDBY state */
+	ret = lp55xx_write(chip, LP5569_REG_ENABLE, 0);
+	if (ret)
+		goto exit;
+
+	/* Wait 1ms for device to enter STANDBY state */
+	usleep_range(1000, 2000);
+
+	/* Set Charge Pump to 1x */
+	ret = lp55xx_update_bits(chip, LP5569_REG_MISC,
+				 FIELD_PREP(LP5569_CP_MODE_MASK, LP55XX_CP_BYPASS),
+				 LP5569_CP_MODE_MASK);
+	if (ret)
+		goto exit;
+
+	/* Enable LED and set to 100% brightness and current to 100% (25.5mA) */
+	for (i = 0; i < pdata->num_channels; i++) {
+		ret = lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + led_tmp->chan_nr,
+				   LED_FULL);
+		if (ret)
+			goto exit;
+
+		ret = lp55xx_write(chip, LP5569_REG_LED_CURRENT_BASE + led_tmp->chan_nr,
+				   LED_FULL);
+		if (ret)
+			goto exit;
+
+		led_tmp++;
+	}
+
+	/* Put Device in NORMAL state */
+	ret = lp55xx_write(chip, LP5569_REG_ENABLE, LP5569_ENABLE);
+	if (ret)
+		goto exit;
+
+	/* Wait 500 us for device to enter NORMAL state */
+	usleep_range(500, 750);
+
+	/* Enable LED Shorted Test */
+	ret = lp55xx_update_bits(chip, LP5569_REG_MISC2, LP5569_LED_OPEN_TEST,
+				 LP5569_LED_SHORT_TEST);
+	if (ret)
+		goto exit;
+
+	/* Wait 500 us for device to fill status regs */
+	usleep_range(500, 750);
+
+	/* Parse status led fault 1 regs */
+	ret = lp55xx_read(chip, LP5569_REG_LED_FAULT1, &status);
+	if (ret < 0)
+		goto exit;
+
+	for (i = 0; i < 8; i++)
+		leds_fault[i] = !!LEDn_STATUS_FAULT(i, status);
+
+	/* Parse status led fault 2 regs */
+	ret = lp55xx_read(chip, LP5569_REG_LED_FAULT2, &status);
+	if (ret < 0)
+		goto exit;
+
+	for (i = 0; i < 1; i++)
+		leds_fault[i + 8] = !!LEDn_STATUS_FAULT(i, status);
+
+	/* Report LED fault */
+	led_tmp = led;
+	for (i = 0; i < pdata->num_channels; i++) {
+		if (leds_fault[led_tmp->chan_nr])
+			pos += sprintf(buf + pos, "LED %d SHORTED FAIL\n",
+				       led_tmp->chan_nr);
+
+		led_tmp++;
+	}
+
+	ret = pos;
+
+exit:
+	/* Disable LED Shorted Test */
+	lp55xx_update_bits(chip, LP5569_REG_MISC2, LP5569_LED_SHORT_TEST,
+			   0);
+
+	led_tmp = led;
+	for (i = 0; i < pdata->num_channels; i++) {
+		lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + led_tmp->chan_nr,
+			     0);
+
+		led_tmp++;
+	}
+
+	return ret;
+}
+
+static ssize_t lp5569_selftest(struct device *dev,
+			       struct device_attribute *attr,
+			       char *buf)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	int i, pos = 0;
+
+	mutex_lock(&chip->lock);
+
+	/* Test LED Open */
+	pos = lp5569_led_open_test(led, buf);
+	if (pos < 0)
+		goto fail;
+
+	/* Test LED Shorted */
+	pos = lp5569_led_short_test(led, buf);
+	if (pos < 0)
+		goto fail;
+
+	for (i = 0; i < chip->pdata->num_channels; i++) {
+		/* Restore current */
+		lp55xx_write(chip, LP5569_REG_LED_CURRENT_BASE + led->chan_nr,
+			     led->led_current);
+
+		/* Restore brightness */
+		lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + led->chan_nr,
+			     led->brightness);
+		led++;
+	}
+
+	if (pos == 0)
+		pos = sprintf(buf, "OK\n");
+	goto release_lock;
+fail:
+	pos = sprintf(buf, "FAIL\n");
+
+release_lock:
+	mutex_unlock(&chip->lock);
+
+	return pos;
+}
+
+#define show_fader(nr)						\
+static ssize_t show_master_fader##nr(struct device *dev,	\
+			    struct device_attribute *attr,	\
+			    char *buf)				\
+{								\
+	return show_master_fader(dev, attr, buf, nr);		\
+}
+
+#define store_fader(nr)						\
+static ssize_t store_master_fader##nr(struct device *dev,	\
+			     struct device_attribute *attr,	\
+			     const char *buf, size_t len)	\
+{								\
+	return store_master_fader(dev, attr, buf, len, nr);	\
+}
+
+static ssize_t show_master_fader(struct device *dev,
+				 struct device_attribute *attr,
+				 char *buf, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	int ret;
+	u8 val;
+
+	mutex_lock(&chip->lock);
+	ret = lp55xx_read(chip, LP5569_REG_MASTER_FADER_BASE + nr - 1, &val);
+	mutex_unlock(&chip->lock);
+
+	if (ret == 0)
+		ret = sprintf(buf, "%u\n", val);
+
+	return ret;
+}
+show_fader(1)
+show_fader(2)
+show_fader(3)
+
+static ssize_t store_master_fader(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t len, int nr)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	int ret;
+	unsigned long val;
+
+	if (kstrtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if (val > 0xff)
+		return -EINVAL;
+
+	mutex_lock(&chip->lock);
+	ret = lp55xx_write(chip, LP5569_REG_MASTER_FADER_BASE + nr - 1,
+			   (u8)val);
+	mutex_unlock(&chip->lock);
+
+	if (ret == 0)
+		ret = len;
+
+	return ret;
+}
+store_fader(1)
+store_fader(2)
+store_fader(3)
+
+static ssize_t show_master_fader_leds(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	int i, ret, pos = 0;
+	u8 val;
+
+	mutex_lock(&chip->lock);
+
+	for (i = 0; i < LP5569_MAX_LEDS; i++) {
+		ret = lp55xx_read(chip, LP5569_REG_LED_CTRL_BASE + i, &val);
+		if (ret)
+			goto leave;
+
+		val = FIELD_PREP(LP5569_FADER_MAPPING_MASK, val);
+		if (val > FIELD_MAX(LP5569_FADER_MAPPING_MASK)) {
+			ret = -EINVAL;
+			goto leave;
+		}
+		buf[pos++] = val + '0';
+	}
+	buf[pos++] = '\n';
+	ret = pos;
+leave:
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+static ssize_t store_master_fader_leds(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf, size_t len)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
+	struct lp55xx_chip *chip = led->chip;
+	int i, n, ret;
+	u8 val;
+
+	n = min_t(int, len, LP5569_MAX_LEDS);
+
+	mutex_lock(&chip->lock);
+
+	for (i = 0; i < n; i++) {
+		if (buf[i] >= '0' && buf[i] <= '7') {
+			val = FIELD_PREP(LP5569_FADER_MAPPING_MASK, buf[i] - '0');
+			ret = lp55xx_update_bits(chip,
+						 LP5569_REG_LED_CTRL_BASE + i,
+						 LP5569_FADER_MAPPING_MASK,
+						 val);
+			if (ret)
+				goto leave;
+		} else {
+			ret = -EINVAL;
+			goto leave;
+		}
+	}
+	ret = len;
+leave:
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+static int lp5569_multicolor_brightness(struct lp55xx_led *led)
+{
+	struct lp55xx_chip *chip = led->chip;
+	int ret;
+	int i;
+
+	mutex_lock(&chip->lock);
+	for (i = 0; i < led->mc_cdev.num_colors; i++) {
+		ret = lp55xx_write(chip,
+				   LP5569_REG_LED_PWM_BASE +
+				   led->mc_cdev.subled_info[i].channel,
+				   led->mc_cdev.subled_info[i].brightness);
+		if (ret)
+			break;
+	}
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+static int lp5569_led_brightness(struct lp55xx_led *led)
+{
+	struct lp55xx_chip *chip = led->chip;
+	int ret;
+
+	mutex_lock(&chip->lock);
+	ret = lp55xx_write(chip, LP5569_REG_LED_PWM_BASE + led->chan_nr,
+			   led->brightness);
+	mutex_unlock(&chip->lock);
+	return ret;
+}
+
+static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
+static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
+static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
+static LP55XX_DEV_ATTR_RW(engine1_leds, show_engine1_leds, store_engine1_leds);
+static LP55XX_DEV_ATTR_RW(engine2_leds, show_engine2_leds, store_engine2_leds);
+static LP55XX_DEV_ATTR_RW(engine3_leds, show_engine3_leds, store_engine3_leds);
+static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
+static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
+static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
+static LP55XX_DEV_ATTR_RO(selftest, lp5569_selftest);
+static LP55XX_DEV_ATTR_RW(master_fader1, show_master_fader1,
+			  store_master_fader1);
+static LP55XX_DEV_ATTR_RW(master_fader2, show_master_fader2,
+			  store_master_fader2);
+static LP55XX_DEV_ATTR_RW(master_fader3, show_master_fader3,
+			  store_master_fader3);
+static LP55XX_DEV_ATTR_RW(master_fader_leds, show_master_fader_leds,
+			  store_master_fader_leds);
+
+static struct attribute *lp5569_attributes[] = {
+	&dev_attr_engine1_mode.attr,
+	&dev_attr_engine2_mode.attr,
+	&dev_attr_engine3_mode.attr,
+	&dev_attr_engine1_load.attr,
+	&dev_attr_engine2_load.attr,
+	&dev_attr_engine3_load.attr,
+	&dev_attr_engine1_leds.attr,
+	&dev_attr_engine2_leds.attr,
+	&dev_attr_engine3_leds.attr,
+	&dev_attr_selftest.attr,
+	&dev_attr_master_fader1.attr,
+	&dev_attr_master_fader2.attr,
+	&dev_attr_master_fader3.attr,
+	&dev_attr_master_fader_leds.attr,
+	NULL,
+};
+
+static const struct attribute_group lp5569_group = {
+	.attrs = lp5569_attributes,
+};
+
+/* Chip specific configurations */
+static struct lp55xx_device_config lp5569_cfg = {
+	.reset = {
+		.addr = LP5569_REG_RESET,
+		.val  = LP5569_RESET,
+	},
+	.enable = {
+		.addr = LP5569_REG_ENABLE,
+		.val  = LP5569_ENABLE,
+	},
+	.max_channel  = LP5569_MAX_LEDS,
+	.post_init_device   = lp5569_post_init_device,
+	.brightness_fn      = lp5569_led_brightness,
+	.multicolor_brightness_fn = lp5569_multicolor_brightness,
+	.set_led_current    = lp5569_set_led_current,
+	.firmware_cb        = lp5569_firmware_loaded,
+	.run_engine         = lp5569_run_engine,
+	.dev_attr_group     = &lp5569_group,
+};
+
+static int lp5569_probe(struct i2c_client *client)
+{
+	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
+	const struct i2c_device_id *id = i2c_client_get_device_id(client);
+	struct device_node *np = dev_of_node(&client->dev);
+	struct lp55xx_chip *chip;
+	struct lp55xx_led *led;
+	int ret;
+
+	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->cfg = &lp5569_cfg;
+
+	if (!pdata) {
+		if (np) {
+			pdata = lp55xx_of_populate_pdata(&client->dev, np,
+							 chip);
+			if (IS_ERR(pdata))
+				return PTR_ERR(pdata);
+		} else {
+			dev_err(&client->dev, "no platform data\n");
+			return -EINVAL;
+		}
+	}
+
+	led = devm_kcalloc(&client->dev,
+			   pdata->num_channels, sizeof(*led), GFP_KERNEL);
+	if (!led)
+		return -ENOMEM;
+
+	chip->cl = client;
+	chip->pdata = pdata;
+
+	mutex_init(&chip->lock);
+
+	i2c_set_clientdata(client, led);
+
+	ret = lp55xx_init_device(chip);
+	if (ret)
+		goto err_init;
+
+	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);
+
+	ret = lp55xx_register_leds(led, chip);
+	if (ret)
+		goto err_out;
+
+	ret = lp55xx_register_sysfs(chip);
+	if (ret) {
+		dev_err(&client->dev, "registering sysfs failed\n");
+		goto err_out;
+	}
+
+	return 0;
+
+err_out:
+	lp55xx_deinit_device(chip);
+err_init:
+	return ret;
+}
+
+static void lp5569_remove(struct i2c_client *client)
+{
+	struct lp55xx_led *led = i2c_get_clientdata(client);
+	struct lp55xx_chip *chip = led->chip;
+
+	lp5569_stop_all_engines(chip);
+	lp55xx_unregister_sysfs(chip);
+	lp55xx_deinit_device(chip);
+}
+
+static const struct i2c_device_id lp5569_id[] = {
+	{ "lp5569",  LP5569 },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(i2c, lp5569_id);
+
+static const struct of_device_id of_lp5569_leds_match[] = {
+	{ .compatible = "ti,lp5569", },
+	{},
+};
+
+MODULE_DEVICE_TABLE(of, of_lp5569_leds_match);
+
+static struct i2c_driver lp5569_driver = {
+	.driver = {
+		.name	= "lp5569x",
+		.of_match_table = of_lp5569_leds_match,
+	},
+	.probe		= lp5569_probe,
+	.remove		= lp5569_remove,
+	.id_table	= lp5569_id,
+};
+
+module_i2c_driver(lp5569_driver);
+
+MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
+MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
+MODULE_AUTHOR("Christian Marangi <ansuelsmth@gmail.com>");
+MODULE_DESCRIPTION("LP5569 LED engine");
+MODULE_LICENSE("GPL");
-- 
2.43.0


  parent reply	other threads:[~2024-05-15 14:31 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-05-15 14:31 [PATCH 1/3] dt-bindings: leds-lp55xx: limit pwr-sel property to ti,lp8501 Christian Marangi
2024-05-15 14:31 ` [PATCH 2/3] dt-bindings: leds-lp55xx: Add new ti,lp5569 compatible Christian Marangi
2024-05-15 15:35   ` Conor Dooley
2024-05-15 14:31 ` Christian Marangi [this message]
2024-05-16 18:20   ` [PATCH 3/3] leds: leds-lp5569: Add support for Texas Instruments LP5569 kernel test robot
2024-05-18 12:46   ` kernel test robot

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