From: Nobuhiro Iwamatsu <iwamatsu@xxxxxxxxxxx>
Add a driver for the PWM controller on Toshiba Visconti ARM SoC.
Signed-off-by: Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@xxxxxxxxxxxxx>
---
drivers/pwm/Kconfig | 9 +++
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-visconti.c | 141 +++++++++++++++++++++++++++++++++++++
3 files changed, 151 insertions(+)
create mode 100644 drivers/pwm/pwm-visconti.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index cb8d739067d2..f99d48f74c76 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -533,6 +533,15 @@ config PWM_TIEHRPWM
To compile this driver as a module, choose M here: the module
will be called pwm-tiehrpwm.
+config PWM_VISCONTI
+ tristate "Toshiba Visconti PWM support"
+ depends on ARCH_VISCONTI || COMPILE_TEST
+ help
+ PWM Subsystem driver support for Toshiba Visconti SoCs.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-visconti.
+
config PWM_TWL
tristate "TWL4030/6030 PWM support"
depends on TWL4030_CORE
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index a59c710e98c7..ef6dc1af7c17 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -51,6 +51,7 @@ obj-$(CONFIG_PWM_SUN4I) += pwm-sun4i.o
obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o
obj-$(CONFIG_PWM_TIECAP) += pwm-tiecap.o
obj-$(CONFIG_PWM_TIEHRPWM) += pwm-tiehrpwm.o
+obj-$(CONFIG_PWM_VISCONTI) += pwm-visconti.o
obj-$(CONFIG_PWM_TWL) += pwm-twl.o
obj-$(CONFIG_PWM_TWL_LED) += pwm-twl-led.o
obj-$(CONFIG_PWM_VT8500) += pwm-vt8500.o
diff --git a/drivers/pwm/pwm-visconti.c b/drivers/pwm/pwm-visconti.c
new file mode 100644
index 000000000000..601450111166
--- /dev/null
+++ b/drivers/pwm/pwm-visconti.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Toshiba Visconti pulse-width-modulation controller driver
+ *
+ * Copyright (c) 2020 TOSHIBA CORPORATION
+ * Copyright (c) 2020 Toshiba Electronic Devices & Storage Corporation
+ * Copyright (c) 2020 Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@xxxxxxxxxxxxx>
+ *
+ */
+
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/pwm.h>
+#include <linux/platform_device.h>
+
+#define PWMC0_PWMACT BIT(5)
+
+#define REG_PCSR(ch) (0x400 + 4 * (ch))
+#define REG_PDUT(ch) (0x420 + 4 * (ch))
+#define REG_PWM0(ch) (0x440 + 4 * (ch))
+
+struct visconti_pwm_chip {
+ struct pwm_chip chip;
+ struct device *dev;
+ void __iomem *base;
+};
+
+#define to_visconti_chip(chip) \
+ container_of(chip, struct visconti_pwm_chip, chip)
+
+static int visconti_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct visconti_pwm_chip *priv = to_visconti_chip(chip);
+ u32 period, duty, pwmc0;
+
+ dev_dbg(priv->dev, "%s: ch = %d en = %d p = 0x%llx d = 0x%llx\n", __func__,
+ pwm->hwpwm, state->enabled, state->period, state->duty_cycle);
+ if (state->enabled) {
+ period = state->period / 1000;
+ duty = state->duty_cycle / 1000;
+ if (period < 0x10000)
+ pwmc0 = 0;
+ else if (period < 0x20000)
+ pwmc0 = 1;
+ else if (period < 0x40000)
+ pwmc0 = 2;
+ else if (period < 0x80000)
+ pwmc0 = 3;
+ else
+ return -EINVAL;
+
+ if (pwmc0) {
+ period /= BIT(pwmc0);
+ duty /= BIT(pwmc0);
+ }
+
+ if (state->polarity == PWM_POLARITY_INVERSED)
+ pwmc0 |= PWMC0_PWMACT;
+
+ writel(pwmc0, priv->base + REG_PWM0(pwm->hwpwm));
+ writel(duty, priv->base + REG_PDUT(pwm->hwpwm));
+ writel(period, priv->base + REG_PCSR(pwm->hwpwm));
+ } else {
+ writel(0, priv->base + REG_PCSR(pwm->hwpwm));
+ }
+
+ return 0;
+}
+
+static const struct pwm_ops visconti_pwm_ops = {
+ .apply = visconti_pwm_apply,
+ .owner = THIS_MODULE,
+};
+
+static int visconti_pwm_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct visconti_pwm_chip *priv;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = &pdev->dev;
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->base)) {
+ dev_err(dev, "unable to map I/O space\n");
+ return PTR_ERR(priv->base);
+ }
+
+ platform_set_drvdata(pdev, priv);
+
+ priv->chip.dev = dev;
+ priv->chip.ops = &visconti_pwm_ops;
+ priv->chip.base = -1;
+ priv->chip.npwm = 4;
+
+ ret = pwmchip_add(&priv->chip);
+ if (ret < 0) {
+ dev_err(dev, "Cannot register visconti PWM: %d\n", ret);
+ return ret;
+ }
+
+ dev_info(&pdev->dev, "visconti PWM registered\n");
+
+ return 0;
+}
+
+static int visconti_pwm_remove(struct platform_device *pdev)
+{
+ struct visconti_pwm_chip *priv = platform_get_drvdata(pdev);
+
+ return pwmchip_remove(&priv->chip);
+}
+
+static const struct of_device_id visconti_pwm_of_match[] = {
+ { .compatible = "toshiba,pwm-visconti", },
+ { }
+};
+
+MODULE_DEVICE_TABLE(of, visconti_pwm_of_match);
+
+static struct platform_driver visconti_pwm_driver = {
+ .driver = {
+ .name = "pwm-visconti",
+ .of_match_table = visconti_pwm_of_match,
+ },
+ .probe = visconti_pwm_probe,
+ .remove = visconti_pwm_remove,
+};
+
+module_platform_driver(visconti_pwm_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Toshiba");
+MODULE_ALIAS("platform:visconti-pwm");
--
2.27.0
