From: Kamel Bouhara <kamel.bouhara@xxxxxxxxxxx>
Add driver for Maxim Integrated MAX7360 PWM controller, supporting up to
8 independent PWM outputs.
Signed-off-by: Kamel Bouhara <kamel.bouhara@xxxxxxxxxxx>
Co-developed-by: Mathieu Dubois-Briand <mathieu.dubois-briand@xxxxxxxxxxx>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@xxxxxxxxxxx>
---
drivers/pwm/Kconfig | 11 +++
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-max7360.c | 194 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 206 insertions(+)
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 0915c1e7df16..930cc7c61b82 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -745,4 +745,15 @@ config PWM_XILINX
To compile this driver as a module, choose M here: the module
will be called pwm-xilinx.
+config PWM_MAX7360
+ tristate "MAX7360 PWMs"
+ depends on MFD_MAX7360
+ select PINCTRL_MAX7360
+ help
+ PWM driver for Maxim Integrated MAX7360 multifunction device, with
+ support for up to 8 PWM outputs.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-max7360.
+
endif
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 9081e0c0e9e0..ae8908ffc892 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -36,6 +36,7 @@ obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o
obj-$(CONFIG_PWM_LPSS) += pwm-lpss.o
obj-$(CONFIG_PWM_LPSS_PCI) += pwm-lpss-pci.o
obj-$(CONFIG_PWM_LPSS_PLATFORM) += pwm-lpss-platform.o
+obj-$(CONFIG_PWM_MAX7360) += pwm-max7360.o
obj-$(CONFIG_PWM_MESON) += pwm-meson.o
obj-$(CONFIG_PWM_MEDIATEK) += pwm-mediatek.o
obj-$(CONFIG_PWM_MICROCHIP_CORE) += pwm-microchip-core.o
diff --git a/drivers/pwm/pwm-max7360.c b/drivers/pwm/pwm-max7360.c
new file mode 100644
index 000000000000..059b39df791d
--- /dev/null
+++ b/drivers/pwm/pwm-max7360.c
@@ -0,0 +1,194 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2025 Bootlin
+ *
+ * Author: Kamel BOUHARA <kamel.bouhara@xxxxxxxxxxx>
+ * Author: Mathieu Dubois-Briand <mathieu.dubois-briand@xxxxxxxxxxx>
+ *
+ * Limitations:
+ * - Only supports normal polarity.
+ * - The period is fixed to 2 ms.
+ * - Only the duty cycle can be changed, new values are applied at the beginning
+ * of the next cycle.
+ * - When disabled, the output is put in Hi-Z.
+ */
+#include <linux/bits.h>
+#include <linux/dev_printk.h>
+#include <linux/err.h>
+#include <linux/math64.h>
+#include <linux/mfd/max7360.h>
+#include <linux/minmax.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/regmap.h>
+#include <linux/time.h>
+#include <linux/types.h>
+
+#define MAX7360_NUM_PWMS 8
+#define MAX7360_PWM_MAX_RES 255
+#define MAX7360_PWM_PERIOD_NS (2 * NSEC_PER_MSEC)
+
+struct max7360_pwm_waveform {
+ u8 duty_steps;
+ bool enabled;
+};
+
+static int max7360_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct regmap *regmap;
+ struct device *dev;
+ int ret;
+
+ regmap = pwmchip_get_drvdata(chip);
+ dev = regmap_get_device(regmap);
+
+ ret = regmap_write_bits(regmap, MAX7360_REG_PWMCFG(pwm->hwpwm),
+ MAX7360_PORT_CFG_COMMON_PWM, 0);
+ if (ret)
+ return ret;
+
+ return regmap_write_bits(regmap, MAX7360_REG_PORTS, BIT(pwm->hwpwm), BIT(pwm->hwpwm));
+}
+
+static void max7360_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct regmap *regmap;
+ struct device *dev;
+
+ regmap = pwmchip_get_drvdata(chip);
+ dev = regmap_get_device(regmap);
+}
+
+static int max7360_pwm_round_waveform_tohw(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ const struct pwm_waveform *wf,
+ void *_wfhw)
+{
+ struct max7360_pwm_waveform *wfhw = _wfhw;
+ u64 duty_steps;
+
+ /*
+ * Ignore user provided values for period_length_ns and duty_offset_ns:
+ * we only support fixed period of MAX7360_PWM_PERIOD_NS and offset of 0.
+ */
+ duty_steps = mul_u64_u64_div_u64(wf->duty_length_ns, MAX7360_PWM_MAX_RES,
+ MAX7360_PWM_PERIOD_NS);
+
+ wfhw->duty_steps = min(MAX7360_PWM_MAX_RES, duty_steps);
+ wfhw->enabled = (wf->duty_length_ns != 0);
+
+ return 0;
+}
+
+static int max7360_pwm_round_waveform_fromhw(struct pwm_chip *chip, struct pwm_device *pwm,
+ const void *_wfhw, struct pwm_waveform *wf)
+{
+ const struct max7360_pwm_waveform *wfhw = _wfhw;
+
+ wf->period_length_ns = wfhw->enabled ? MAX7360_PWM_PERIOD_NS : 0;
+ wf->duty_offset_ns = 0;
+ wf->duty_length_ns = DIV64_U64_ROUND_UP(wfhw->duty_steps * MAX7360_PWM_PERIOD_NS,
+ MAX7360_PWM_MAX_RES);
+
+ return 0;
+}
+
+static int max7360_pwm_write_waveform(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ const void *_wfhw)
+{
+ const struct max7360_pwm_waveform *wfhw = _wfhw;
+ struct regmap *regmap;
+ unsigned int val;
+ int ret;
+
+ regmap = pwmchip_get_drvdata(chip);
+ val = (wfhw->enabled) ? BIT(pwm->hwpwm) : 0;
+ ret = regmap_write_bits(regmap, MAX7360_REG_GPIOCTRL, BIT(pwm->hwpwm), val);
+ if (ret)
+ return ret;
+
+ if (wfhw->duty_steps)
+ return regmap_write(regmap, MAX7360_REG_PWM(pwm->hwpwm), wfhw->duty_steps);
+
+ return 0;
+}
+
+static int max7360_pwm_read_waveform(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ void *_wfhw)
+{
+ struct max7360_pwm_waveform *wfhw = _wfhw;
+ struct regmap *regmap;
+ unsigned int val;
+ int ret;
+
+ regmap = pwmchip_get_drvdata(chip);
+
+ ret = regmap_read(regmap, MAX7360_REG_GPIOCTRL, &val);
+ if (ret)
+ return ret;
+
+ if (val & BIT(pwm->hwpwm)) {
+ wfhw->enabled = true;
+ ret = regmap_read(regmap, MAX7360_REG_PWM(pwm->hwpwm), &val);
+ wfhw->duty_steps = val;
+ } else {
+ wfhw->enabled = false;
+ wfhw->duty_steps = 0;
+ }
+
+ return ret;
+}
+
+static const struct pwm_ops max7360_pwm_ops = {
+ .request = max7360_pwm_request,
+ .free = max7360_pwm_free,
+ .round_waveform_tohw = max7360_pwm_round_waveform_tohw,
+ .round_waveform_fromhw = max7360_pwm_round_waveform_fromhw,
+ .read_waveform = max7360_pwm_read_waveform,
+ .write_waveform = max7360_pwm_write_waveform,
+};
+
+static int max7360_pwm_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pwm_chip *chip;
+ struct regmap *regmap;
+ int ret;
+
+ if (!dev->parent)
+ return dev_err_probe(dev, -ENODEV, "no parent device\n");
+
+ chip = devm_pwmchip_alloc(dev->parent, MAX7360_NUM_PWMS, 0);
+ if (IS_ERR(chip))
+ return PTR_ERR(chip);
+ chip->ops = &max7360_pwm_ops;
+
+ regmap = dev_get_regmap(dev->parent, NULL);
+ if (!regmap)
+ return dev_err_probe(dev, -ENODEV, "could not get parent regmap\n");
+
+ pwmchip_set_drvdata(chip, regmap);
+
+ ret = devm_pwmchip_add(dev, chip);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to add PWM chip\n");
+
+ return 0;
+}
+
+static struct platform_driver max7360_pwm_driver = {
+ .driver = {
+ .name = "max7360-pwm",
+ },
+ .probe = max7360_pwm_probe,
+};
+module_platform_driver(max7360_pwm_driver);
+
+MODULE_DESCRIPTION("MAX7360 PWM driver");
+MODULE_AUTHOR("Kamel BOUHARA <kamel.bouhara@xxxxxxxxxxx>");
+MODULE_AUTHOR("Mathieu Dubois-Briand <mathieu.dubois-briand@xxxxxxxxxxx>");
+MODULE_LICENSE("GPL");
--
2.39.5
