[PATCH v3 2/2] pwm: Add Nuvoton MA35D1 PWM controller support
Chi-Wen Weng
cwweng.linux at gmail.com
Fri Dec 6 00:55:01 PST 2024
This commit adds a generic PWM framework driver for Nuvoton MA35D1 PWM controller.
Signed-off-by: Chi-Wen Weng <cwweng.linux at gmail.com>
---
drivers/pwm/Kconfig | 9 ++
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-ma35d1.c | 179 +++++++++++++++++++++++++++++++++++++++
3 files changed, 189 insertions(+)
create mode 100644 drivers/pwm/pwm-ma35d1.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 0915c1e7df16..97b9e83af020 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -411,6 +411,15 @@ config PWM_LPSS_PLATFORM
To compile this driver as a module, choose M here: the module
will be called pwm-lpss-platform.
+config PWM_MA35D1
+ tristate "Nuvoton MA35D1 PWM support"
+ depends on ARCH_MA35 || COMPILE_TEST
+ help
+ Generic PWM framework driver for Nuvoton MA35D1.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-ma35d1.
+
config PWM_MESON
tristate "Amlogic Meson PWM driver"
depends on ARCH_MESON || COMPILE_TEST
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 9081e0c0e9e0..c1d3a1d8add0 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-$(CONFIG_PWM_MA35D1) += pwm-ma35d1.o
obj-$(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-ma35d1.c b/drivers/pwm/pwm-ma35d1.c
new file mode 100644
index 000000000000..380f17b20a3d
--- /dev/null
+++ b/drivers/pwm/pwm-ma35d1.c
@@ -0,0 +1,179 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the Nuvoton MA35D1 PWM controller
+ *
+ * Copyright (C) 2024 Nuvoton Corporation
+ * Chi-Wen Weng <cwweng at nuvoton.com>
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/math64.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+/* The following are registers address offset for MA35D1 PWM controller */
+#define MA35D1_REG_PWM_CTL0 (0x00)
+#define MA35D1_REG_PWM_CNTEN (0x20)
+#define MA35D1_REG_PWM_PERIOD0 (0x30)
+#define MA35D1_REG_PWM_CMPDAT0 (0x50)
+#define MA35D1_REG_PWM_WGCTL0 (0xB0)
+#define MA35D1_REG_PWM_POLCTL (0xD4)
+#define MA35D1_REG_PWM_POEN (0xD8)
+
+/* The following are register address of MA35D1 PWM controller */
+#define MA35D1_PWM_CH_REG_SIZE 4
+#define MA35D1_PWM_CMPDAT0_ADDR(base, ch) ((base) + MA35D1_REG_PWM_CMPDAT0 + \
+ ((ch) * MA35D1_PWM_CH_REG_SIZE))
+#define MA35D1_PWM_CNTEN_ADDR(base) ((base) + MA35D1_REG_PWM_CNTEN)
+#define MA35D1_PWM_PERIOD0_ADDR(base, ch) ((base) + MA35D1_REG_PWM_PERIOD0 + \
+ ((ch) * MA35D1_PWM_CH_REG_SIZE))
+#define MA35D1_PWM_POEN_ADDR(base) ((base) + MA35D1_REG_PWM_POEN)
+#define MA35D1_PWM_POLCTL_ADDR(base) ((base) + MA35D1_REG_PWM_POLCTL)
+
+#define MA35D1_PWM_MAX_COUNT 0xFFFF
+#define MA35D1_PWM_TOTAL_CHANNELS 6
+
+struct nuvoton_pwm {
+ void __iomem *base;
+ u64 clkrate;
+};
+
+static inline struct nuvoton_pwm *to_nuvoton_pwm(struct pwm_chip *chip)
+{
+ return pwmchip_get_drvdata(chip);
+}
+
+static int nuvoton_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct nuvoton_pwm *nvtpwm;
+ u32 ch = pwm->hwpwm;
+
+ nvtpwm = to_nuvoton_pwm(chip);
+ if (state->enabled) {
+ u64 duty_cycles, period_cycles;
+
+ /* Calculate the duty and period cycles */
+ duty_cycles = mul_u64_u64_div_u64(nvtpwm->clkrate,
+ state->duty_cycle, NSEC_PER_SEC);
+ if (duty_cycles > MA35D1_PWM_MAX_COUNT)
+ duty_cycles = MA35D1_PWM_MAX_COUNT;
+
+ period_cycles = mul_u64_u64_div_u64(nvtpwm->clkrate,
+ state->period, NSEC_PER_SEC);
+ if (period_cycles > MA35D1_PWM_MAX_COUNT)
+ period_cycles = MA35D1_PWM_MAX_COUNT;
+
+ /* Write the duty and period cycles to registers */
+ writel(duty_cycles, MA35D1_PWM_CMPDAT0_ADDR(nvtpwm->base, ch));
+ writel(period_cycles, MA35D1_PWM_PERIOD0_ADDR(nvtpwm->base, ch));
+ /* Enable counter */
+ writel(readl(MA35D1_PWM_CNTEN_ADDR(nvtpwm->base)) | BIT(ch),
+ MA35D1_PWM_CNTEN_ADDR(nvtpwm->base));
+ /* Enable output */
+ writel(readl(MA35D1_PWM_POEN_ADDR(nvtpwm->base)) | BIT(ch),
+ MA35D1_PWM_POEN_ADDR(nvtpwm->base));
+ } else {
+ /* Disable counter */
+ writel(readl(MA35D1_PWM_CNTEN_ADDR(nvtpwm->base)) & ~BIT(ch),
+ MA35D1_PWM_CNTEN_ADDR(nvtpwm->base));
+ /* Disable output */
+ writel(readl(MA35D1_PWM_POEN_ADDR(nvtpwm->base)) & ~BIT(ch),
+ MA35D1_PWM_POEN_ADDR(nvtpwm->base));
+ }
+
+ /* Set polarity state to register */
+ if (state->polarity == PWM_POLARITY_NORMAL)
+ writel(readl(MA35D1_PWM_POLCTL_ADDR(nvtpwm->base)) & ~BIT(ch),
+ MA35D1_PWM_POLCTL_ADDR(nvtpwm->base));
+ else
+ writel(readl(MA35D1_PWM_POLCTL_ADDR(nvtpwm->base)) | BIT(ch),
+ MA35D1_PWM_POLCTL_ADDR(nvtpwm->base));
+
+ return 0;
+}
+
+static int nuvoton_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct nuvoton_pwm *nvtpwm;
+ u32 duty_cycles, period_cycles, cnten, outen, polarity;
+ u32 ch = pwm->hwpwm;
+
+ nvtpwm = to_nuvoton_pwm(chip);
+
+ cnten = readl(MA35D1_PWM_CNTEN_ADDR(nvtpwm->base));
+ outen = readl(MA35D1_PWM_POEN_ADDR(nvtpwm->base));
+ duty_cycles = readl(MA35D1_PWM_CMPDAT0_ADDR(nvtpwm->base, ch));
+ period_cycles = readl(MA35D1_PWM_PERIOD0_ADDR(nvtpwm->base, ch));
+ polarity = readl(MA35D1_PWM_POLCTL_ADDR(nvtpwm->base)) & BIT(ch);
+
+ state->enabled = (cnten & BIT(ch)) && (outen & BIT(ch));
+ state->polarity = polarity ? PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
+ state->duty_cycle = DIV64_U64_ROUND_UP((u64)duty_cycles * NSEC_PER_SEC, nvtpwm->clkrate);
+ state->period = DIV64_U64_ROUND_UP((u64)period_cycles * NSEC_PER_SEC, nvtpwm->clkrate);
+
+ return 0;
+}
+
+static const struct pwm_ops nuvoton_pwm_ops = {
+ .apply = nuvoton_pwm_apply,
+ .get_state = nuvoton_pwm_get_state,
+};
+
+static int nuvoton_pwm_probe(struct platform_device *pdev)
+{
+ struct pwm_chip *chip;
+ struct nuvoton_pwm *nvtpwm;
+ struct clk *clk;
+ int ret;
+
+ chip = devm_pwmchip_alloc(&pdev->dev, MA35D1_PWM_TOTAL_CHANNELS, sizeof(*nvtpwm));
+ if (IS_ERR(chip))
+ return PTR_ERR(chip);
+
+ nvtpwm = to_nuvoton_pwm(chip);
+
+ nvtpwm->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(nvtpwm->base))
+ return PTR_ERR(nvtpwm->base);
+
+ clk = devm_clk_get_enabled(&pdev->dev, NULL);
+ if (IS_ERR(clk))
+ return dev_err_probe(&pdev->dev, PTR_ERR(clk), "unable to get the clock");
+
+ nvtpwm->clkrate = clk_get_rate(clk);
+ if (nvtpwm->clkrate > NSEC_PER_SEC)
+ return dev_err_probe(&pdev->dev, -EINVAL, "pwm clock out of range");
+
+ chip->ops = &nuvoton_pwm_ops;
+ chip->atomic = true;
+
+ ret = devm_pwmchip_add(&pdev->dev, chip);
+ if (ret < 0)
+ return dev_err_probe(&pdev->dev, ret, "unable to add pwm chip");
+
+ return 0;
+}
+
+static const struct of_device_id nuvoton_pwm_of_match[] = {
+ { .compatible = "nuvoton,ma35d1-pwm" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, nuvoton_pwm_of_match);
+
+static struct platform_driver nuvoton_pwm_driver = {
+ .probe = nuvoton_pwm_probe,
+ .driver = {
+ .name = "nuvoton-pwm",
+ .of_match_table = nuvoton_pwm_of_match,
+ },
+};
+module_platform_driver(nuvoton_pwm_driver);
+
+MODULE_AUTHOR("Chi-Wen Weng <cwweng at nuvoton.com>");
+MODULE_DESCRIPTION("Nuvoton MA35D1 PWM driver");
+MODULE_LICENSE("GPL");
--
2.25.1
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