* [PATCH 4/6] leds: tahvo: Driver for Tahvo/Betty ASIC LEDPWM output
2021-12-24 21:56 [PATCH 3/6] ARM: dts: omap2420-n810: Add Tahvo/Betty LEDPWM and Vcore bindings peter.vasil
@ 2021-12-24 21:56 ` peter.vasil
2022-02-03 7:13 ` Tony Lindgren
2021-12-24 21:56 ` [PATCH 5/6] regulator: tahvo-vcore: Add basic Tahvo/Betty ASIC Vcore output support peter.vasil
2021-12-24 21:56 ` [PATCH 6/6] mfd: retu: Add support for LEDPWM and Vcore regulator MFD cells peter.vasil
2 siblings, 1 reply; 5+ messages in thread
From: peter.vasil @ 2021-12-24 21:56 UTC (permalink / raw)
To: linux-omap; +Cc: peter.vasil
From: Peter Vasil <peter.vasil@gmail.com>
Nokia Tahvo/Betty ASIC is a companion chip for mobile devices. One of
its outputs is a 127-levels PWM, usually used for LED or backlight
control.
Register control code has been written based on original Nokia kernel
sources for N810 display driver.
Driver expects a regmap device as parent, usually retu-mfd driver bound
to the Tahvo ASIC.
---
drivers/leds/Kconfig | 12 ++++++
drivers/leds/Makefile | 1 +
drivers/leds/leds-tahvo.c | 85 +++++++++++++++++++++++++++++++++++++++
3 files changed, 98 insertions(+)
create mode 100644 drivers/leds/leds-tahvo.c
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index ed800f5da7d8..010d455a2151 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -871,6 +871,18 @@ config LEDS_ACER_A500
This option enables support for the Power Button LED of
Acer Iconia Tab A500.
+config LEDS_TAHVO
+ tristate "Tahvo PWM led support"
+ depends on LEDS_CLASS && MFD_RETU
+ help
+ Tahvo PWM LED driver for Nokia Internet Tablets (770, N800,
+ N810). At least on N810 the LCD backlight is controlled by
+ Tahvo/Betty MFD.
+
+ To compile this driver as a module, choose M here: the
+ module will be called leds-tahvo.
+
+
source "drivers/leds/blink/Kconfig"
comment "Flash and Torch LED drivers"
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index c636ec069612..30832d3bc947 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -87,6 +87,7 @@ obj-$(CONFIG_LEDS_TURRIS_OMNIA) += leds-turris-omnia.o
obj-$(CONFIG_LEDS_WM831X_STATUS) += leds-wm831x-status.o
obj-$(CONFIG_LEDS_WM8350) += leds-wm8350.o
obj-$(CONFIG_LEDS_WRAP) += leds-wrap.o
+obj-$(CONFIG_LEDS_TAHVO) += leds-tahvo.o
# LED SPI Drivers
obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o
diff --git a/drivers/leds/leds-tahvo.c b/drivers/leds/leds-tahvo.c
new file mode 100644
index 000000000000..53feb0749e76
--- /dev/null
+++ b/drivers/leds/leds-tahvo.c
@@ -0,0 +1,85 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Tahvo LED PWM driver
+ *
+ * Copyright (C) 2004, 2005 Nokia Corporation
+ *
+ * Based on original 2.6 kernel driver for Nokia N8x0 LCD panel.
+ * Rewritten by Peter Vasil.
+ */
+
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+
+#define TAHVO_REG_LEDPWM 0x05
+
+/* Maximum power/brightness value */
+#define TAHVO_LEDPWM_MAX 127
+
+struct tahvo_led {
+ struct led_classdev cdev;
+ struct regmap *regmap;
+};
+
+static int tahvo_led_brightness_set(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ struct tahvo_led *led = container_of(cdev, struct tahvo_led, cdev);
+
+ return regmap_write(led->regmap, TAHVO_REG_LEDPWM, brightness);
+}
+
+static int tahvo_led_probe(struct platform_device *pdev)
+{
+ struct tahvo_led *led;
+ struct led_init_data init_data;
+ int ret;
+
+ led = devm_kzalloc(&pdev->dev, sizeof(*led), GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ if (pdev->dev.of_node && pdev->dev.of_node->name) {
+ led->cdev.name = pdev->dev.of_node->name;
+ } else {
+ dev_warn(&pdev->dev, "No OF node found, using default name!\n");
+ led->cdev.name = "tahvo:led";
+ }
+
+ led->cdev.max_brightness = TAHVO_LEDPWM_MAX;
+ led->cdev.brightness_set_blocking = tahvo_led_brightness_set;
+
+ led->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+
+ init_data.fwnode = of_fwnode_handle(pdev->dev.of_node);
+
+ ret = devm_led_classdev_register_ext(&pdev->dev, &led->cdev, &init_data);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register PWM LED (%d)\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id of_tahvo_leds_match[] = {
+ { .compatible = "nokia,tahvo-ledpwm", },
+ {},
+};
+
+static struct platform_driver tahvo_led_driver = {
+ .probe = tahvo_led_probe,
+ .driver = {
+ .name = "tahvo-ledpwm",
+ .of_match_table = of_match_ptr(of_tahvo_leds_match),
+ },
+};
+module_platform_driver(tahvo_led_driver);
+
+MODULE_ALIAS("platform:tahvo-ledpwm");
+MODULE_DESCRIPTION("Tahvo LED PWM");
+MODULE_AUTHOR("Peter Vasil <peter.vasil@gmail.com>");
+MODULE_LICENSE("GPL");
--
2.25.1
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH 5/6] regulator: tahvo-vcore: Add basic Tahvo/Betty ASIC Vcore output support
2021-12-24 21:56 [PATCH 3/6] ARM: dts: omap2420-n810: Add Tahvo/Betty LEDPWM and Vcore bindings peter.vasil
2021-12-24 21:56 ` [PATCH 4/6] leds: tahvo: Driver for Tahvo/Betty ASIC LEDPWM output peter.vasil
@ 2021-12-24 21:56 ` peter.vasil
2021-12-24 21:56 ` [PATCH 6/6] mfd: retu: Add support for LEDPWM and Vcore regulator MFD cells peter.vasil
2 siblings, 0 replies; 5+ messages in thread
From: peter.vasil @ 2021-12-24 21:56 UTC (permalink / raw)
To: linux-omap; +Cc: peter.vasil
From: Peter Vasil <peter.vasil@gmail.com>
Nokia Tahvo/Betty ASIC is a companion chip for mobile devices. One of
its outputs is a Vcore adjustable voltage regulator.
Register control code has been written based on original Nokia kernel
sources for N810 display driver.
Driver expects a regmap device as parent, usually retu-mfd driver bound
to the Tahvo ASIC.
---
drivers/regulator/Kconfig | 8 ++
drivers/regulator/Makefile | 1 +
drivers/regulator/tahvo-vcore-regulator.c | 104 ++++++++++++++++++++++
3 files changed, 113 insertions(+)
create mode 100644 drivers/regulator/tahvo-vcore-regulator.c
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 6be9b1c8a615..16c684c742cf 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -1404,6 +1404,14 @@ config REGULATOR_WM8994
This driver provides support for the voltage regulators on the
WM8994 CODEC.
+config REGULATOR_TAHVO_VCORE
+ tristate "Tahvo/Betty Vcore regulator support"
+ depends on MFD_RETU
+ help
+ This driver supports Vcore voltage control on Nokia's Tahvo/Betty
+ ASIC chip. The regulator controls framebuffer supply voltage in
+ Nokia internet tablets (for sure at least N810).
+
config REGULATOR_QCOM_LABIBB
tristate "QCOM LAB/IBB regulator support"
depends on SPMI || COMPILE_TEST
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b07d2a22df0b..ed64d2cf8a42 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -170,5 +170,6 @@ obj-$(CONFIG_REGULATOR_WM831X) += wm831x-ldo.o
obj-$(CONFIG_REGULATOR_WM8350) += wm8350-regulator.o
obj-$(CONFIG_REGULATOR_WM8400) += wm8400-regulator.o
obj-$(CONFIG_REGULATOR_WM8994) += wm8994-regulator.o
+obj-$(CONFIG_REGULATOR_TAHVO_VCORE) += tahvo-vcore-regulator.o
ccflags-$(CONFIG_REGULATOR_DEBUG) += -DDEBUG
diff --git a/drivers/regulator/tahvo-vcore-regulator.c b/drivers/regulator/tahvo-vcore-regulator.c
new file mode 100644
index 000000000000..a7c92aa7a148
--- /dev/null
+++ b/drivers/regulator/tahvo-vcore-regulator.c
@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright (C) 2004, 2005 Nokia Corporation
+//
+// Based on original 2.6 kernel driver for Nokia N8x0 LCD panel.
+// Rewritten in 2021 by Peter Vasil <petervasil@gmail.com>.
+//
+// Driver for Nokia Betty/Tahvo Vcore regulator
+// The only known voltages are currently 1.005V==0x0f and 1.475V==0x00 with mask 0x0f
+// Whether the sequence is actually linear is only a guess.
+
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+#define TAHVO_REG_VCORE 0x07
+
+// Values in this table are simply interpolated from the only known min/max.
+static const unsigned int tahvo_vcore_voltages[] = {
+ 1475000, 1443667, 1412333, 1381000, 1349667, 1318333, 1287000, 1255667,
+ 1224333, 1193000, 1161667, 1130333, 1099000, 1067667, 1036333, 1005000,
+};
+
+static const struct regulator_ops tahvo_vcore_regulator_voltage_ops = {
+ .list_voltage = regulator_list_voltage_table,
+ .map_voltage = regulator_map_voltage_iterate,
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+};
+
+static const struct regulator_desc vcore_regulator = {
+ .name = "vcore",
+ .ops = &tahvo_vcore_regulator_voltage_ops,
+ .type = REGULATOR_VOLTAGE,
+ .owner = THIS_MODULE,
+ .volt_table = tahvo_vcore_voltages,
+ .n_voltages = ARRAY_SIZE(tahvo_vcore_voltages),
+ .vsel_reg = TAHVO_REG_VCORE,
+ .vsel_mask = 0x0f,
+};
+
+static const struct regmap_config tahvo_vcore_regmap_config = {
+ .reg_bits = 8,
+ .reg_stride = 1,
+ .val_bits = 16,
+};
+
+static int tahvo_vcore_regulator_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct regulator_init_data *init_data;
+ struct regulator_config cfg = {};
+ struct regulator_dev *rdev;
+
+ init_data = of_get_regulator_init_data(dev, dev->of_node,
+ &vcore_regulator);
+ if (!init_data) {
+ dev_err(dev, "Failed to init regulator data!\n");
+ return -EINVAL;
+ }
+
+ cfg.dev = dev;
+ cfg.init_data = init_data;
+ cfg.of_node = dev->of_node;
+
+ cfg.regmap = dev_get_regmap(dev->parent, NULL);
+ if (!cfg.regmap) {
+ dev_err(dev, "failed to locate regmap\n");
+ return -ENODEV;
+ }
+
+ rdev = devm_regulator_register(dev, &vcore_regulator, &cfg);
+ if (IS_ERR(rdev)) {
+ dev_err(dev, "Failed to register regulator: %ld\n",
+ PTR_ERR(rdev));
+ return PTR_ERR(rdev);
+ }
+ platform_set_drvdata(pdev, rdev);
+
+ return 0;
+}
+
+static const struct of_device_id regulator_tahvo_vcore_of_match[] = {
+ { .compatible = "nokia,tahvo-vcore-regulator", },
+ {},
+};
+
+static struct platform_driver tahvo_vcore_regulator_driver = {
+ .probe = tahvo_vcore_regulator_probe,
+ .driver = {
+ .name = "tahvo-vcore-regulator",
+ .of_match_table = of_match_ptr(regulator_tahvo_vcore_of_match),
+ },
+};
+module_platform_driver(tahvo_vcore_regulator_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Peter Vasil <petervasil@gmail.com>");
+MODULE_DESCRIPTION("Tahvo/Betty Vcore voltage regulator");
--
2.25.1
^ permalink raw reply related [flat|nested] 5+ messages in thread