[PATCH v1 2/2] hwmon: npcm-pwm: add NPCM7xx PWM driver
From: Tomer Maimon
Date: Tue May 29 2018 - 06:14:19 EST
Add Nuvoton BMC NPCM7xx Pulse Width Modulation (PWM) driver.
The Nuvoton BMC NPCM7xx has two identical PWM controller modules,
each module has four PWM controller outputs.
Signed-off-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
---
drivers/hwmon/Kconfig | 6 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/npcm7xx-pwm.c | 363 ++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 370 insertions(+)
create mode 100644 drivers/hwmon/npcm7xx-pwm.c
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 6ec307c93ece..693ba09cff8e 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1891,6 +1891,12 @@ config SENSORS_XGENE
If you say yes here you get support for the temperature
and power sensors for APM X-Gene SoC.
+config SENSORS_NPCM7XX
+ tristate "Nuvoton NPCM7XX PWM driver"
+ help
+ This driver provides support for Nuvoton NPCM7XX PWM
+ controller.
+
if ACPI
comment "ACPI drivers"
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index e7d52a36e6c4..24aad895a3bb 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -174,6 +174,7 @@ obj-$(CONFIG_SENSORS_W83L786NG) += w83l786ng.o
obj-$(CONFIG_SENSORS_WM831X) += wm831x-hwmon.o
obj-$(CONFIG_SENSORS_WM8350) += wm8350-hwmon.o
obj-$(CONFIG_SENSORS_XGENE) += xgene-hwmon.o
+obj-$(CONFIG_SENSORS_NPCM7XX) += npcm7xx-pwm.o
obj-$(CONFIG_PMBUS) += pmbus/
diff --git a/drivers/hwmon/npcm7xx-pwm.c b/drivers/hwmon/npcm7xx-pwm.c
new file mode 100644
index 000000000000..6122ca82b94d
--- /dev/null
+++ b/drivers/hwmon/npcm7xx-pwm.c
@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2014-2018 Nuvoton Technology corporation.
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/sysfs.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+/* NPCM7XX PWM port base address */
+#define NPCM7XX_PWM_REG_PR 0x0
+#define NPCM7XX_PWM_REG_CSR 0x4
+#define NPCM7XX_PWM_REG_CR 0x8
+#define NPCM7XX_PWM_REG_CNRx(PORT) (0xC + (12 * PORT))
+#define NPCM7XX_PWM_REG_CMRx(PORT) (0x10 + (12 * PORT))
+#define NPCM7XX_PWM_REG_PDRx(PORT) (0x14 + (12 * PORT))
+#define NPCM7XX_PWM_REG_PIER 0x3C
+#define NPCM7XX_PWM_REG_PIIR 0x40
+
+#define NPCM7XX_PWM_CTRL_CH0_MODE_BIT BIT(3)
+#define NPCM7XX_PWM_CTRL_CH1_MODE_BIT BIT(11)
+#define NPCM7XX_PWM_CTRL_CH2_MODE_BIT BIT(15)
+#define NPCM7XX_PWM_CTRL_CH3_MODE_BIT BIT(19)
+
+#define NPCM7XX_PWM_CTRL_CH0_INV_BIT BIT(2)
+#define NPCM7XX_PWM_CTRL_CH1_INV_BIT BIT(10)
+#define NPCM7XX_PWM_CTRL_CH2_INV_BIT BIT(14)
+#define NPCM7XX_PWM_CTRL_CH3_INV_BIT BIT(18)
+
+#define NPCM7XX_PWM_CTRL_CH0_EN_BIT BIT(0)
+#define NPCM7XX_PWM_CTRL_CH1_EN_BIT BIT(8)
+#define NPCM7XX_PWM_CTRL_CH2_EN_BIT BIT(12)
+#define NPCM7XX_PWM_CTRL_CH3_EN_BIT BIT(16)
+
+/* Define the maximum PWM channel number */
+#define NPCM7XX_PWM_MAX_CHN_NUM 8
+#define NPCM7XX_PWM_MAX_CHN_NUM_IN_A_MODULE 4
+#define NPCM7XX_PWM_MAX_MODULES 2
+
+/* Define the Counter Register, value = 100 for match 100% */
+#define NPCM7XX_PWM_COUNTER_DEFALUT_NUM 255
+#define NPCM7XX_PWM_COMPARATOR_DEFALUT_NUM 127
+
+#define NPCM7XX_PWM_COMPARATOR_MAX 255
+
+
+/* default all PWM channels PRESCALE2 = 1 */
+#define NPCM7XX_PWM_PRESCALE2_DEFALUT_CH0 0x4
+#define NPCM7XX_PWM_PRESCALE2_DEFALUT_CH1 0x40
+#define NPCM7XX_PWM_PRESCALE2_DEFALUT_CH2 0x400
+#define NPCM7XX_PWM_PRESCALE2_DEFALUT_CH3 0x4000
+
+#define PWM_OUTPUT_FREQ_25KHZ 25000
+#define PWN_CNT_DEFAULT 256
+#define MIN_PRESCALE1 2
+#define NPCM7XX_PWM_PRESCALE_SHIFT_CH01 8
+
+#define NPCM7XX_PWM_PRESCALE2_DEFALUT (NPCM7XX_PWM_PRESCALE2_DEFALUT_CH0 | \
+ NPCM7XX_PWM_PRESCALE2_DEFALUT_CH1 | \
+ NPCM7XX_PWM_PRESCALE2_DEFALUT_CH2 | \
+ NPCM7XX_PWM_PRESCALE2_DEFALUT_CH3)
+
+#define NPCM7XX_PWM_CTRL_MODE_DEFALUT (NPCM7XX_PWM_CTRL_CH0_MODE_BIT | \
+ NPCM7XX_PWM_CTRL_CH1_MODE_BIT | \
+ NPCM7XX_PWM_CTRL_CH2_MODE_BIT | \
+ NPCM7XX_PWM_CTRL_CH3_MODE_BIT)
+
+#define NPCM7XX_PWM_CTRL_EN_DEFALUT (NPCM7XX_PWM_CTRL_CH0_EN_BIT | \
+ NPCM7XX_PWM_CTRL_CH1_EN_BIT | \
+ NPCM7XX_PWM_CTRL_CH2_EN_BIT | \
+ NPCM7XX_PWM_CTRL_CH3_EN_BIT)
+
+struct npcm7xx_pwm_data {
+ unsigned long clk_freq;
+ void __iomem *pwm_base[NPCM7XX_PWM_MAX_MODULES];
+ struct mutex npcm7xx_pwm_lock[NPCM7XX_PWM_MAX_CHN_NUM];
+};
+
+static const struct of_device_id pwm_dt_id[];
+
+static int npcm7xx_pwm_config_set(struct npcm7xx_pwm_data *data, int channel,
+ u16 val)
+{
+ u32 PWMChannel = (channel % NPCM7XX_PWM_MAX_CHN_NUM_IN_A_MODULE);
+ u32 n_module = (channel / NPCM7XX_PWM_MAX_CHN_NUM_IN_A_MODULE);
+ u32 u32TmpBuf = 0, ctrl_en_bit;
+
+ /*
+ * Config PWM Comparator register for setting duty cycle
+ */
+ if (val < 0 || val > NPCM7XX_PWM_COMPARATOR_MAX)
+ return -EINVAL;
+
+ /* write new CMR value */
+ iowrite32(val, data->pwm_base[n_module] +
+ NPCM7XX_PWM_REG_CMRx(PWMChannel));
+
+ u32TmpBuf = ioread32(data->pwm_base[n_module] + NPCM7XX_PWM_REG_CR);
+
+ switch (PWMChannel) {
+ case 0:
+ ctrl_en_bit = NPCM7XX_PWM_CTRL_CH0_EN_BIT;
+ break;
+ case 1:
+ ctrl_en_bit = NPCM7XX_PWM_CTRL_CH1_EN_BIT;
+ break;
+ case 2:
+ ctrl_en_bit = NPCM7XX_PWM_CTRL_CH2_EN_BIT;
+ break;
+ case 3:
+ ctrl_en_bit = NPCM7XX_PWM_CTRL_CH3_EN_BIT;
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ if (val == 0)
+ /* Disable PWM */
+ u32TmpBuf &= ~(ctrl_en_bit);
+ else
+ /* Enable PWM */
+ u32TmpBuf |= ctrl_en_bit;
+
+ mutex_lock(&data->npcm7xx_pwm_lock[n_module]);
+ iowrite32(u32TmpBuf, data->pwm_base[n_module] + NPCM7XX_PWM_REG_CR);
+ mutex_unlock(&data->npcm7xx_pwm_lock[n_module]);
+
+ return 0;
+}
+
+static int npcm7xx_read_pwm(struct device *dev, u32 attr, int channel,
+ long *val)
+{
+ struct npcm7xx_pwm_data *data = dev_get_drvdata(dev);
+ u32 PWMChannel = (channel % NPCM7XX_PWM_MAX_CHN_NUM_IN_A_MODULE);
+ u32 n_module = (channel / NPCM7XX_PWM_MAX_CHN_NUM_IN_A_MODULE);
+
+ if (IS_ERR(data))
+ return PTR_ERR(data);
+
+ switch (attr) {
+ case hwmon_pwm_input:
+ *val = (long)ioread32(data->pwm_base[n_module] +
+ NPCM7XX_PWM_REG_CMRx(PWMChannel));
+ return 0;
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int npcm7xx_write_pwm(struct device *dev, u32 attr, int channel,
+ long val)
+{
+ struct npcm7xx_pwm_data *data = dev_get_drvdata(dev);
+ int err = 0;
+
+ switch (attr) {
+ case hwmon_pwm_input:
+ err = npcm7xx_pwm_config_set(data, channel, (u16)val);
+ break;
+ default:
+ err = -EOPNOTSUPP;
+ break;
+ }
+
+ return err;
+}
+
+static umode_t npcm7xx_pwm_is_visible(const void *_data, u32 attr, int channel)
+{
+ switch (attr) {
+ case hwmon_pwm_input:
+ return 0644;
+ default:
+ return 0;
+ }
+}
+
+static int npcm7xx_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ switch (type) {
+ case hwmon_pwm:
+ return npcm7xx_read_pwm(dev, attr, channel, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int npcm7xx_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ switch (type) {
+ case hwmon_pwm:
+ return npcm7xx_write_pwm(dev, attr, channel, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static umode_t npcm7xx_is_visible(const void *data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ switch (type) {
+ case hwmon_pwm:
+ return npcm7xx_pwm_is_visible(data, attr, channel);
+ default:
+ return 0;
+ }
+}
+
+static const u32 npcm7xx_pwm_config[] = {
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ HWMON_PWM_INPUT,
+ 0
+};
+
+static const struct hwmon_channel_info npcm7xx_pwm = {
+ .type = hwmon_pwm,
+ .config = npcm7xx_pwm_config,
+};
+
+static const struct hwmon_channel_info *npcm7xx_info[] = {
+ &npcm7xx_pwm,
+ NULL
+};
+
+static const struct hwmon_ops npcm7xx_hwmon_ops = {
+ .is_visible = npcm7xx_is_visible,
+ .read = npcm7xx_read,
+ .write = npcm7xx_write,
+};
+
+static const struct hwmon_chip_info npcm7xx_chip_info = {
+ .ops = &npcm7xx_hwmon_ops,
+ .info = npcm7xx_info,
+};
+
+static int npcm7xx_pwm_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct npcm7xx_pwm_data *data;
+ struct resource res[NPCM7XX_PWM_MAX_MODULES];
+ struct device *hwmon;
+ struct clk *clk;
+ int m, ch, res_cnt, ret;
+ u32 Prescale_val, output_freq;
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ for (res_cnt = 0; res_cnt < NPCM7XX_PWM_MAX_MODULES ; res_cnt++) {
+ ret = of_address_to_resource(dev->of_node, res_cnt,
+ &res[res_cnt]);
+ if (ret) {
+ pr_err("PWM of_address_to_resource fail ret %d\n",
+ ret);
+ return -EINVAL;
+ }
+
+ data->pwm_base[res_cnt] =
+ devm_ioremap_resource(dev, &(res[res_cnt]));
+ pr_debug("pwm%d base is 0x%08X, res.start 0x%08X , size 0x%08X\n",
+ res_cnt, (u32)data->pwm_base[res_cnt],
+ res[res_cnt].start, resource_size(&(res[res_cnt])));
+
+ if (!data->pwm_base[res_cnt]) {
+ pr_err("pwm probe failed: can't read pwm base address for resource %d.\n",
+ res_cnt);
+ return -ENOMEM;
+ }
+
+ mutex_init(&data->npcm7xx_pwm_lock[res_cnt]);
+ }
+
+ clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(clk))
+ return -ENODEV;
+
+ data->clk_freq = clk_get_rate(clk);
+
+ /* Adjust NPCM7xx PWMs output frequency to ~25Khz */
+ output_freq = data->clk_freq / PWN_CNT_DEFAULT;
+ Prescale_val = DIV_ROUND_CLOSEST(output_freq, PWM_OUTPUT_FREQ_25KHZ);
+
+ /* If Prescale_val = 0, then the prescale output clock is stopped */
+ if (Prescale_val < MIN_PRESCALE1)
+ Prescale_val = MIN_PRESCALE1;
+ /*
+ * Prescale_val need to decrement in one because in the PWM Prescale
+ * register the Prescale value increment by one
+ */
+ Prescale_val--;
+
+ /* Setting PWM Prescale Register value register to both modules */
+ Prescale_val |= (Prescale_val << NPCM7XX_PWM_PRESCALE_SHIFT_CH01);
+
+ for (m = 0; m < NPCM7XX_PWM_MAX_MODULES ; m++) {
+ iowrite32(Prescale_val,
+ data->pwm_base[m] + NPCM7XX_PWM_REG_PR);
+ iowrite32(NPCM7XX_PWM_PRESCALE2_DEFALUT,
+ data->pwm_base[m] + NPCM7XX_PWM_REG_CSR);
+ iowrite32(NPCM7XX_PWM_CTRL_MODE_DEFALUT,
+ data->pwm_base[m] + NPCM7XX_PWM_REG_CR);
+
+ for (ch = 0; ch < NPCM7XX_PWM_MAX_CHN_NUM; ch++) {
+ iowrite32(NPCM7XX_PWM_COUNTER_DEFALUT_NUM,
+ data->pwm_base[m] + NPCM7XX_PWM_REG_CNRx(ch));
+ iowrite32(NPCM7XX_PWM_COMPARATOR_DEFALUT_NUM,
+ data->pwm_base[m] + NPCM7XX_PWM_REG_CMRx(ch));
+ }
+
+ iowrite32(NPCM7XX_PWM_CTRL_MODE_DEFALUT |
+ NPCM7XX_PWM_CTRL_EN_DEFALUT,
+ data->pwm_base[m] + NPCM7XX_PWM_REG_CR);
+ }
+
+ hwmon = devm_hwmon_device_register_with_info(dev, "npcm7xx_pwm", data,
+ &npcm7xx_chip_info, NULL);
+
+ if (IS_ERR(hwmon)) {
+ pr_err("PWM Driver failed - devm_hwmon_device_register_with_groups failed\n");
+ return PTR_ERR(hwmon);
+ }
+
+ pr_info("NPCM7XX PWM Driver probed, PWM output Freq %dHz\n",
+ output_freq / ((Prescale_val & 0xf) + 1));
+
+ return 0;
+}
+
+static const struct of_device_id of_pwm_match_table[] = {
+ { .compatible = "nuvoton,npcm750-pwm", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_pwm_match_table);
+
+static struct platform_driver npcm7xx_pwm_driver = {
+ .probe = npcm7xx_pwm_probe,
+ .driver = {
+ .name = "npcm7xx_pwm",
+ .of_match_table = of_pwm_match_table,
+ },
+};
+
+module_platform_driver(npcm7xx_pwm_driver);
+
+MODULE_DESCRIPTION("Nuvoton NPCM7XX PWM Driver");
+MODULE_AUTHOR("Tomer Maimon <tomer.maimon@xxxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.14.1