[PATCH 1/4] pwm: add freescale ftm pwm driver support
Xiubo Li
Li.Xiubo at freescale.com
Tue Aug 20 23:07:39 EDT 2013
Add freescale ftm pwm driver support. The ftm pwm device
can be found on Vybrid VF610 and Layerscape LS-1 SoCs.
Signed-off-by: Xiubo Li <Li.Xiubo at freescale.com>
Signed-off-by: Jingchang Lu <b35083 at freescale.com>
---
drivers/pwm/Kconfig | 10 +
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-fsl-ftm.c | 586 ++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 597 insertions(+)
create mode 100644 drivers/pwm/pwm-fsl-ftm.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 75840b5..247b4c3 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -62,6 +62,16 @@ config PWM_BFIN
To compile this driver as a module, choose M here: the module
will be called pwm-bfin.
+config PWM_FTM
+ tristate "Freescale FTM PWM support"
+ depends on OF
+ help
+ Generic FTM PWM framework driver for Freescale VF610 and
+ Layerscape LS-1 SoCs.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-ftm.
+
config PWM_IMX
tristate "i.MX PWM support"
depends on ARCH_MXC
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index 77a8c18..0e7f6ae 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -3,6 +3,7 @@ obj-$(CONFIG_PWM_SYSFS) += sysfs.o
obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o
obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o
obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o
+obj-$(CONFIG_PWM_FTM) += pwm-fsl-ftm.o
obj-$(CONFIG_PWM_IMX) += pwm-imx.o
obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o
obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o
diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
new file mode 100644
index 0000000..f10ed34
--- /dev/null
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -0,0 +1,586 @@
+/*
+ * Freescale FTM PWM Driver
+ *
+ * Copyright 2013 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <linux/of_address.h>
+#include <linux/pinctrl/consumer.h>
+
+#define FTM_SC 0x00
+#define FTMSC_CPWMS (0x1 << 5)
+#define FTMSC_CLK_MASK 0x03
+#define FTMSC_CLK_OFFSET 0x03
+#define FTMSC_CLKSYS (0x01 << 3)
+#define FTMSC_CLKFIX (0x02 << 3)
+#define FTMSC_CLKEXT (0x03 << 3)
+#define FTMSC_PS_MASK 0x07
+#define FTMSC_PS_OFFSET 0x00
+
+#define FTM_CNT 0x04
+#define FTM_MOD 0x08
+
+#define FTM_CSC_BASE 0x0C
+#define FTM_CSC(_CHANNEL) \
+ (FTM_CSC_BASE + (_CHANNEL * 0x08))
+#define FTMCnSC_MSB (0x01 << 5)
+#define FTMCnSC_MSA (0x01 << 4)
+#define FTMCnSC_ELSB (0x01 << 3)
+#define FTMCnSC_ELSA (0x01 << 2)
+#define FTM_PWMMODE (FTMCnSC_MSB)
+#define FTM_HIGH_TRUE (FTMCnSC_ELSB)
+#define FTM_LOW_TRUE (FTMCnSC_ELSA)
+
+#define FTM_CV_BASE 0x10
+#define FTM_CV(_CHANNEL) \
+ (FTM_CV_BASE + (_CHANNEL * 0x08))
+
+#define FTM_CNTIN 0x4C
+#define FTM_STATUS 0x50
+
+#define FTM_MODE 0x54
+#define FTMMODE_FTMEN (0x01 << 0)
+#define FTMMODE_INIT (0x01 << 2)
+#define FTMMODE_PWMSYNC (0x01 << 3)
+
+#define FTM_SYNC 0x58
+#define FTM_OUTINIT 0x5C
+#define FTM_OUTMASK 0x60
+#define FTM_COMBINE 0x64
+#define FTM_DEADTIME 0x68
+#define FTM_EXTTRIG 0x6C
+#define FTM_POL 0x70
+#define FTM_FMS 0x74
+#define FTM_FILTER 0x78
+#define FTM_FLTCTRL 0x7C
+#define FTM_QDCTRL 0x80
+#define FTM_CONF 0x84
+#define FTM_FLTPOL 0x88
+#define FTM_SYNCONF 0x8C
+#define FTM_INVCTRL 0x90
+#define FTM_SWOCTRL 0x94
+#define FTM_PWMLOAD 0x98
+
+#define FTM_MAX_CHANNEL 0x08
+#define FTM_CNTIN_VAL 0x00
+
+struct fsl_pwm {
+ unsigned long period_cycles;
+ unsigned long duty_cycles;
+};
+
+struct fsl_pwm_chip {
+ struct mutex lock;
+
+ struct platform_device *pdev;
+ struct pwm_chip chip;
+
+ unsigned int clk_ps;
+ struct clk *clk;
+
+ void __iomem *base;
+
+ unsigned int cpwm;
+ struct fsl_pwm fpwms[FTM_MAX_CHANNEL];
+
+ /* pinctrl handles */
+ struct pinctrl *pinctrl;
+};
+
+static inline struct fsl_pwm_chip *to_fsl_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct fsl_pwm_chip, chip);
+}
+
+static int fsl_pwm_request_channel(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ int ret = 0;
+ struct fsl_pwm_chip *fpc;
+
+ fpc = to_fsl_chip(chip);
+
+ ret = clk_prepare_enable(fpc->clk);
+ if (ret) {
+ dev_err(&fpc->pdev->dev,
+ "failed to clk_prepare_enable "
+ "ftm pwm module clock : %d\n",
+ ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void fsl_pwm_free_channel(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ struct fsl_pwm_chip *fpc;
+
+ fpc = to_fsl_chip(chip);
+
+ clk_disable_unprepare(fpc->clk);
+}
+
+/* For center-aligned PWM:
+ * period = 2*(MOD - CNTIN)
+ * duty = 2*(CnV - CNTIN)
+ * For edge-aligend PWM:
+ * period = MOD - CNTIN + 1
+ * duty = CnV - CNTIN
+ */
+static int fsl_updata_config(struct fsl_pwm_chip *fpc,
+ struct pwm_device *pwm)
+{
+ int i;
+ unsigned long reg, cntin = FTM_CNTIN_VAL;
+ struct pwm_chip *chip = &fpc->chip;
+
+ reg = readl(fpc->base + FTM_SC);
+ reg &= ~(FTMSC_CPWMS);
+ reg |= (fpc->cpwm ? FTMSC_CPWMS : 0x00);
+ writel(reg, fpc->base + FTM_SC);
+
+ if (pwm && fpc->cpwm) {
+ writel(fpc->fpwms[pwm->hwpwm].period_cycles / 2 + cntin,
+ fpc->base + FTM_MOD);
+ writel(fpc->fpwms[pwm->hwpwm].duty_cycles / 2 + cntin,
+ fpc->base + FTM_CV(pwm->hwpwm));
+ } else if (pwm) {
+ writel(fpc->fpwms[pwm->hwpwm].period_cycles + cntin - 1,
+ fpc->base + FTM_MOD);
+ writel(fpc->fpwms[pwm->hwpwm].duty_cycles + cntin,
+ fpc->base + FTM_CV(pwm->hwpwm));
+ }
+
+ if (pwm)
+ return 0;
+
+ for (i = 0; i < chip->npwm; i++) {
+ if (!test_bit(PWMF_ENABLED, &chip->pwms[i].flags))
+ continue;
+ if (fpc->cpwm) {
+ writel(fpc->fpwms[i].period_cycles / 2 + cntin,
+ fpc->base + FTM_MOD);
+ writel(fpc->fpwms[i].duty_cycles / 2 + cntin,
+ fpc->base + FTM_CV(i));
+ } else {
+ writel(fpc->fpwms[i].period_cycles + cntin - 1,
+ fpc->base + FTM_MOD);
+ writel(fpc->fpwms[i].duty_cycles + cntin,
+ fpc->base + FTM_CV(i));
+ }
+ }
+
+ return 0;
+}
+
+static unsigned long
+fsl_rate_to_cycles(struct fsl_pwm_chip *fpc, int time_ns)
+{
+ unsigned long ps;
+ unsigned long long c;
+
+ ps = (0x01 << fpc->clk_ps);
+
+ /* The module clk is HZ/s, the time_ns parameter
+ * is based nanosecond, so here should divide
+ * 1000000000UL.
+ */
+ c = clk_get_rate(fpc->clk);
+ c = c * time_ns;
+ do_div(c, 1000000000UL);
+ do_div(c, ps);
+
+ return (unsigned long)c;
+}
+
+static int fsl_pwm_config_channel(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ int duty_ns,
+ int period_ns)
+{
+ unsigned long period_cycles, duty_cycles;
+ struct fsl_pwm_chip *fpc;
+
+ fpc = to_fsl_chip(chip);
+
+ if (WARN_ON(!test_bit(PWMF_REQUESTED, &pwm->flags)))
+ return -ESHUTDOWN;
+
+ period_cycles = fsl_rate_to_cycles(fpc, period_ns);
+ if (period_cycles > 0xFFFF) {
+ dev_warn(&fpc->pdev->dev,
+ "required PWM period cycles(%lu) "
+ "overflow 16-bits counter!\n",
+ period_cycles);
+ period_cycles = 0xFFFF;
+ }
+
+ duty_cycles = fsl_rate_to_cycles(fpc, duty_ns);
+ if (duty_cycles >= 0xFFFF) {
+ dev_warn(&fpc->pdev->dev,
+ "required PWM duty cycles(%lu) "
+ "overflow 16-bits counter!\n",
+ duty_cycles);
+ duty_cycles = 0xFFFF - 1;
+ }
+
+ fpc->fpwms[pwm->hwpwm].period_cycles = period_cycles;
+ fpc->fpwms[pwm->hwpwm].duty_cycles = duty_cycles;
+
+ writel(FTM_PWMMODE | FTM_HIGH_TRUE,
+ fpc->base + FTM_CSC(pwm->hwpwm));
+
+ writel(0xF0, fpc->base + FTM_OUTMASK);
+ writel(0x0F, fpc->base + FTM_OUTINIT);
+ writel(FTM_CNTIN_VAL, fpc->base + FTM_CNTIN);
+
+ mutex_lock(&fpc->lock);
+ fsl_updata_config(fpc, pwm);
+ mutex_unlock(&fpc->lock);
+
+ return 0;
+}
+
+static int fsl_pwm_set_channel_polarity(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ enum pwm_polarity polarity)
+{
+ unsigned long reg;
+ struct fsl_pwm_chip *fpc;
+
+ fpc = to_fsl_chip(chip);
+
+ reg = readl(fpc->base + FTM_POL);
+ reg &= ~(0x01 << pwm->hwpwm);
+ reg |= (polarity << pwm->hwpwm);
+ writel(reg, fpc->base + FTM_POL);
+
+ return 0;
+}
+
+static int is_any_other_channel_enabled(struct pwm_chip *chip,
+ unsigned int cur)
+{
+ int i;
+
+ for (i = 0; i < chip->npwm; i++) {
+ if (i == cur)
+ continue;
+ if (test_bit(PWMF_ENABLED, &chip->pwms[i].flags))
+ return 1;
+ }
+
+ return 0;
+}
+
+static int fsl_pwm_enable_channel(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ int ret;
+ unsigned long reg;
+ struct fsl_pwm_chip *fpc;
+ struct pinctrl_state *pins_state;
+ const char *statename;
+
+ fpc = to_fsl_chip(chip);
+
+ if (WARN_ON(!test_bit(PWMF_REQUESTED, &pwm->flags)))
+ return -ESHUTDOWN;
+
+ statename = kasprintf(GFP_KERNEL, "en%d", pwm->hwpwm);
+ pins_state = pinctrl_lookup_state(fpc->pinctrl,
+ statename);
+ /* enable pins to be muxed in and configured */
+ if (!IS_ERR(pins_state)) {
+ ret = pinctrl_select_state(fpc->pinctrl, pins_state);
+ if (ret)
+ dev_warn(&fpc->pdev->dev,
+ "could not set default pins\n");
+ } else
+ dev_warn(&fpc->pdev->dev,
+ "could not get default pinstate\n");
+
+ if (is_any_other_channel_enabled(chip, pwm->hwpwm))
+ return 0;
+
+ reg = readl(fpc->base + FTM_SC);
+ reg &= ~((FTMSC_CLK_MASK << FTMSC_CLK_OFFSET) |
+ (FTMSC_PS_MASK << FTMSC_PS_OFFSET));
+ /* select system clock source */
+ reg |= (FTMSC_CLKSYS | fpc->clk_ps);
+ writel(reg, fpc->base + FTM_SC);
+
+ return 0;
+}
+
+static void fsl_pwm_disable_channel(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ int ret;
+ unsigned long reg;
+ struct fsl_pwm_chip *fpc;
+ struct pinctrl_state *pins_state;
+ const char *statename;
+
+ fpc = to_fsl_chip(chip);
+
+ statename = kasprintf(GFP_KERNEL, "ds%d", pwm->hwpwm);
+ pins_state = pinctrl_lookup_state(fpc->pinctrl,
+ statename);
+ /* enable pins to be muxed in and configured */
+ if (!IS_ERR(pins_state)) {
+ ret = pinctrl_select_state(fpc->pinctrl, pins_state);
+ if (ret)
+ dev_warn(&fpc->pdev->dev,
+ "could not set default pins\n");
+ } else
+ dev_warn(&fpc->pdev->dev,
+ "could not get default pinstate\n");
+
+ if (WARN_ON(!test_bit(PWMF_REQUESTED, &pwm->flags)))
+ return;
+
+ if (is_any_other_channel_enabled(chip, pwm->hwpwm))
+ return;
+
+ writel(0xFF, fpc->base + FTM_OUTMASK);
+ reg = readl(fpc->base + FTM_SC);
+ reg &= ~(FTMSC_CLK_MASK << FTMSC_CLK_OFFSET);
+ writel(reg, fpc->base + FTM_SC);
+}
+
+static const struct pwm_ops fsl_pwm_ops = {
+ .request = fsl_pwm_request_channel,
+ .free = fsl_pwm_free_channel,
+ .config = fsl_pwm_config_channel,
+ .set_polarity = fsl_pwm_set_channel_polarity,
+ .enable = fsl_pwm_enable_channel,
+ .disable = fsl_pwm_disable_channel,
+ .owner = THIS_MODULE,
+};
+
+static ssize_t fsl_pwm_cpwm_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct fsl_pwm_chip *fpc;
+
+ fpc = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", fpc->cpwm);
+}
+
+static ssize_t fsl_pwm_cpwm_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ int ret;
+ unsigned int val;
+ struct fsl_pwm_chip *fpc;
+
+ fpc = dev_get_drvdata(dev);
+
+ ret = kstrtouint(buf, 0, &val);
+ if (ret)
+ return ret;
+
+ mutex_lock(&fpc->lock);
+ if (!!(val) != !!(fpc->cpwm)) {
+ fpc->cpwm = !!val;
+ fsl_updata_config(fpc, NULL);
+ }
+ mutex_unlock(&fpc->lock);
+
+ return count;
+}
+
+static DEVICE_ATTR(cpwm, S_IRUGO | S_IWUSR | S_IWGRP,
+ fsl_pwm_cpwm_show, fsl_pwm_cpwm_store);
+
+static struct attribute *fsl_pwm_attrs[] = {
+ &dev_attr_cpwm.attr,
+ NULL
+};
+
+static const struct attribute_group fsl_pwm_attr_group = {
+ .attrs = fsl_pwm_attrs,
+};
+
+static int fsl_pwm_parse_dt(struct fsl_pwm_chip *fpc)
+{
+ int ret = 0;
+ u32 chs[FTM_MAX_CHANNEL];
+ struct device_node *np = fpc->pdev->dev.of_node;
+
+ ret = of_property_read_u32(np, "fsl,pwm-clk-ps",
+ &fpc->clk_ps);
+ if (ret < 0) {
+ dev_err(&fpc->pdev->dev,
+ "failed to get pwm "
+ "clk prescaler : %d\n",
+ ret);
+ return ret;
+ }
+ if (fpc->clk_ps > 7 || fpc->clk_ps < 0)
+ return -EINVAL;
+
+ ret = of_property_read_u32(np, "fsl,pwm-cpwm",
+ &fpc->cpwm);
+ if (ret < 0) {
+ dev_err(&fpc->pdev->dev,
+ "failed to get cpwm "
+ "status: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = of_property_read_u32(np, "fsl,pwm-number",
+ &fpc->chip.npwm);
+ if (ret < 0) {
+ dev_err(&fpc->pdev->dev,
+ "failed to get pwm number: %d\n",
+ ret);
+ return ret;
+ }
+ if (fpc->chip.npwm > FTM_MAX_CHANNEL
+ || fpc->chip.npwm <= 0)
+ return -EINVAL;
+
+ ret = of_property_read_u32_array(np, "fsl,pwm-channels",
+ chs, fpc->chip.npwm);
+ if (ret < 0) {
+ dev_err(&fpc->pdev->dev,
+ "failed to get pwm channel Ids: %d\n",
+ ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int fsl_pwm_probe(struct platform_device *pdev)
+{
+ int ret = 0;
+ struct fsl_pwm_chip *fpc;
+ struct resource *res;
+
+ fpc = devm_kzalloc(&pdev->dev, sizeof(*fpc), GFP_KERNEL);
+ if (!fpc) {
+ dev_err(&pdev->dev,
+ "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ mutex_init(&fpc->lock);
+
+ fpc->pdev = pdev;
+
+ ret = fsl_pwm_parse_dt(fpc);
+ if (ret < 0)
+ return ret;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ fpc->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(fpc->base)) {
+ dev_err(&pdev->dev,
+ "failed to ioremap() registers\n");
+ ret = PTR_ERR(fpc->base);
+ return ret;
+ }
+
+ fpc->chip.dev = &pdev->dev;
+ fpc->chip.ops = &fsl_pwm_ops;
+ fpc->chip.of_xlate = of_pwm_xlate_with_flags;
+ fpc->chip.of_pwm_n_cells = 3;
+ fpc->chip.base = -1;
+
+ ret = pwmchip_add(&fpc->chip);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "failed to add ftm0 pwm chip %d\n",
+ ret);
+ return ret;
+ }
+
+ fpc->clk = devm_clk_get(&pdev->dev, "ftm0");
+ if (IS_ERR(fpc->clk)) {
+ ret = PTR_ERR(fpc->clk);
+ dev_err(&pdev->dev,
+ "failed to get ftm0's module clock %d\n",
+ ret);
+ return ret;
+ }
+
+ fpc->pinctrl = devm_pinctrl_get(&pdev->dev);
+ if (IS_ERR(fpc->pinctrl)) {
+ ret = PTR_ERR(fpc->pinctrl);
+ return ret;
+ }
+
+ ret = sysfs_create_group(&pdev->dev.kobj,
+ &fsl_pwm_attr_group);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "Failed to create sysfs "
+ "attributes, err: %d\n",
+ ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, fpc);
+
+ return 0;
+}
+
+static int fsl_pwm_remove(struct platform_device *pdev)
+{
+ struct fsl_pwm_chip *fpc;
+
+ fpc = platform_get_drvdata(pdev);
+ if (fpc == NULL)
+ return -ENODEV;
+
+ mutex_destroy(&fpc->lock);
+
+ sysfs_remove_group(&pdev->dev.kobj,
+ &fsl_pwm_attr_group);
+
+ return pwmchip_remove(&fpc->chip);
+}
+
+static const struct of_device_id fsl_pwm_dt_ids[] = {
+ { .compatible = "fsl,vf610-ftm-pwm", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, fsl_pwm_dt_ids);
+
+static struct platform_driver fsl_pwm_driver = {
+ .driver = {
+ .name = "fsl-ftm-pwm",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(fsl_pwm_dt_ids),
+ },
+ .probe = fsl_pwm_probe,
+ .remove = fsl_pwm_remove,
+};
+module_platform_driver(fsl_pwm_driver);
+
+MODULE_DESCRIPTION("Freescale FTM PWM Driver");
+MODULE_AUTHOR("Xiubo Li <Li.Xiubo at freescale.com>");
+MODULE_LICENSE("GPL");
--
1.8.0
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