Enable/disable the PWM signal.
0 is disabled
1 is enabled
+
+What: /sys/class/pwm/pwmchipN/pwmX/capture
+Date: June 2016
+KernelVersion: 4.8
+Contact: Lee Jones <lee.jones@linaro.org>
+Description:
+ Capture information about a PWM signal. The output format is a
+ pair unsigned integers (period and duty cycle), separated by a
+ single space.
--- /dev/null
+Broadcom iProc PWM controller device tree bindings
+
+This controller has 4 channels.
+
+Required Properties :
+- compatible: must be "brcm,iproc-pwm"
+- reg: physical base address and length of the controller's registers
+- clocks: phandle + clock specifier pair for the external clock
+- #pwm-cells: Should be 3. See pwm.txt in this directory for a
+ description of the cells format.
+
+Refer to clocks/clock-bindings.txt for generic clock consumer properties.
+
+Example:
+
+pwm: pwm@18031000 {
+ compatible = "brcm,iproc-pwm";
+ reg = <0x18031000 0x28>;
+ clocks = <&osc>;
+ #pwm-cells = <3>;
+};
--- /dev/null
+* PWM controlled by ChromeOS EC
+
+Google's ChromeOS EC PWM is a simple PWM attached to the Embedded Controller
+(EC) and controlled via a host-command interface.
+
+An EC PWM node should be only found as a sub-node of the EC node (see
+Documentation/devicetree/bindings/mfd/cros-ec.txt).
+
+Required properties:
+- compatible: Must contain "google,cros-ec-pwm"
+- #pwm-cells: Should be 1. The cell specifies the PWM index.
+
+Example:
+ cros-ec@0 {
+ compatible = "google,cros-ec-spi";
+
+ ...
+
+ cros_ec_pwm: ec-pwm {
+ compatible = "google,cros-ec-pwm";
+ #pwm-cells = <1>;
+ };
+ };
Tegra SoC PWFM controller
Required properties:
-- compatible: For Tegra20, must contain "nvidia,tegra20-pwm". For Tegra30,
- must contain "nvidia,tegra30-pwm". Otherwise, must contain
- "nvidia,<chip>-pwm", plus one of the above, where <chip> is tegra114,
- tegra124, tegra132, or tegra210.
+- compatible: Must be:
+ - "nvidia,tegra20-pwm": for Tegra20
+ - "nvidia,tegra30-pwm", "nvidia,tegra20-pwm": for Tegra30
+ - "nvidia,tegra114-pwm", "nvidia,tegra20-pwm": for Tegra114
+ - "nvidia,tegra124-pwm", "nvidia,tegra20-pwm": for Tegra124
+ - "nvidia,tegra132-pwm", "nvidia,tegra20-pwm": for Tegra132
+ - "nvidia,tegra210-pwm", "nvidia,tegra20-pwm": for Tegra210
+ - "nvidia,tegra186-pwm": for Tegra186
- reg: physical base address and length of the controller's registers
- #pwm-cells: should be 2. See pwm.txt in this directory for a description of
the cells format.
Example:
-ehrpwm0: ehrpwm@0 { /* EHRPWM on am33xx */
+ehrpwm0: pwm@48300200 { /* EHRPWM on am33xx */
compatible = "ti,am33xx-ehrpwm";
#pwm-cells = <3>;
reg = <0x48300200 0x100>;
ti,hwmods = "ehrpwm0";
};
-ehrpwm0: ehrpwm@0 { /* EHRPWM on da850 */
+ehrpwm0: pwm@300000 { /* EHRPWM on da850 */
compatible = "ti,da850-ehrpwm", "ti,am33xx-ehrpwm";
#pwm-cells = <3>;
reg = <0x300000 0x2000>;
- "renesas,pwm-r8a7790": for R-Car H2
- "renesas,pwm-r8a7791": for R-Car M2-W
- "renesas,pwm-r8a7794": for R-Car E2
+ - "renesas,pwm-r8a7795": for R-Car H3
- reg: base address and length of the registers block for the PWM.
- #pwm-cells: should be 2. See pwm.txt in this directory for a description of
the cells format.
--- /dev/null
+== ST STMPE PWM controller ==
+
+This is a PWM block embedded in the ST Microelectronics STMPE
+(ST Multi-Purpose Expander) chips. The PWM is registered as a
+subdevices of the STMPE MFD device.
+
+Required properties:
+- compatible: should be:
+ - "st,stmpe-pwm"
+- #pwm-cells: should be 2. See pwm.txt in this directory for a description of
+ the cells format.
+
+Example:
+
+pwm0: pwm {
+ compatible = "st,stmpe-pwm";
+ #pwm-cells = <2>;
+};
return ret;
}
EXPORT_SYMBOL(cros_ec_cmd_xfer);
+
+int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *msg)
+{
+ int ret;
+
+ ret = cros_ec_cmd_xfer(ec_dev, msg);
+ if (ret < 0) {
+ dev_err(ec_dev->dev, "Command xfer error (err:%d)\n", ret);
+ } else if (msg->result != EC_RES_SUCCESS) {
+ dev_dbg(ec_dev->dev, "Command result (err: %d)\n", msg->result);
+ return -EPROTO;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(cros_ec_cmd_xfer_status);
To compile this driver as a module, choose M here: the module
will be called pwm-atmel-tcb.
+config PWM_BCM_IPROC
+ tristate "iProc PWM support"
+ depends on ARCH_BCM_IPROC
+ help
+ Generic PWM framework driver for Broadcom iProc PWM block. This
+ block is used in Broadcom iProc SoC's.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-bcm-iproc.
+
config PWM_BCM_KONA
tristate "Kona PWM support"
depends on ARCH_BCM_MOBILE
Generic PWM framework driver for Crystalcove (CRC) PMIC based PWM
control.
+config PWM_CROS_EC
+ tristate "ChromeOS EC PWM driver"
+ depends on MFD_CROS_EC
+ help
+ PWM driver for exposing a PWM attached to the ChromeOS Embedded
+ Controller.
+
config PWM_EP93XX
tristate "Cirrus Logic EP93xx PWM support"
depends on ARCH_EP93XX
config PWM_RCAR
tristate "Renesas R-Car PWM support"
- depends on ARCH_RCAR_GEN1 || ARCH_RCAR_GEN2 || COMPILE_TEST
+ depends on ARCH_RENESAS || COMPILE_TEST
depends on HAS_IOMEM
help
This driver exposes the PWM Timer controller found in Renesas
To compile this driver as a module, choose M here: the module
will be called pwm-sti.
+config PWM_STMPE
+ bool "STMPE expander PWM export"
+ depends on MFD_STMPE
+ help
+ This enables support for the PWMs found in the STMPE I/O
+ expanders.
+
config PWM_SUN4I
tristate "Allwinner PWM support"
depends on ARCH_SUNXI || COMPILE_TEST
obj-$(CONFIG_PWM_ATMEL) += pwm-atmel.o
obj-$(CONFIG_PWM_ATMEL_HLCDC_PWM) += pwm-atmel-hlcdc.o
obj-$(CONFIG_PWM_ATMEL_TCB) += pwm-atmel-tcb.o
+obj-$(CONFIG_PWM_BCM_IPROC) += pwm-bcm-iproc.o
obj-$(CONFIG_PWM_BCM_KONA) += pwm-bcm-kona.o
obj-$(CONFIG_PWM_BCM2835) += pwm-bcm2835.o
obj-$(CONFIG_PWM_BERLIN) += pwm-berlin.o
obj-$(CONFIG_PWM_BRCMSTB) += pwm-brcmstb.o
obj-$(CONFIG_PWM_CLPS711X) += pwm-clps711x.o
obj-$(CONFIG_PWM_CRC) += pwm-crc.o
+obj-$(CONFIG_PWM_CROS_EC) += pwm-cros-ec.o
obj-$(CONFIG_PWM_EP93XX) += pwm-ep93xx.o
obj-$(CONFIG_PWM_FSL_FTM) += pwm-fsl-ftm.o
obj-$(CONFIG_PWM_IMG) += pwm-img.o
obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o
obj-$(CONFIG_PWM_SPEAR) += pwm-spear.o
obj-$(CONFIG_PWM_STI) += pwm-sti.o
+obj-$(CONFIG_PWM_STMPE) += pwm-stmpe.o
obj-$(CONFIG_PWM_SUN4I) += pwm-sun4i.o
obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o
obj-$(CONFIG_PWM_TIECAP) += pwm-tiecap.o
{
int err;
- if (!pwm)
+ if (!pwm || !state || !state->period ||
+ state->duty_cycle > state->period)
return -EINVAL;
if (!memcmp(state, &pwm->state, sizeof(*state)))
}
EXPORT_SYMBOL_GPL(pwm_apply_state);
+/**
+ * pwm_capture() - capture and report a PWM signal
+ * @pwm: PWM device
+ * @result: structure to fill with capture result
+ * @timeout: time to wait, in milliseconds, before giving up on capture
+ *
+ * Returns: 0 on success or a negative error code on failure.
+ */
+int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result,
+ unsigned long timeout)
+{
+ int err;
+
+ if (!pwm || !pwm->chip->ops)
+ return -EINVAL;
+
+ if (!pwm->chip->ops->capture)
+ return -ENOSYS;
+
+ mutex_lock(&pwm_lock);
+ err = pwm->chip->ops->capture(pwm->chip, pwm, result, timeout);
+ mutex_unlock(&pwm_lock);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(pwm_capture);
+
/**
* pwm_adjust_config() - adjust the current PWM config to the PWM arguments
* @pwm: PWM device
chip->chip.of_pwm_n_cells = 3;
chip->chip.can_sleep = 1;
- ret = pwmchip_add(&chip->chip);
+ ret = pwmchip_add_with_polarity(&chip->chip, PWM_POLARITY_INVERSED);
if (ret) {
clk_disable_unprepare(hlcdc->periph_clk);
return ret;
void __iomem *base;
unsigned int updated_pwms;
- struct mutex isr_lock; /* ISR is cleared when read, ensure only one thread does that */
+ /* ISR is cleared when read, ensure only one thread does that */
+ struct mutex isr_lock;
void (*config)(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long dty, unsigned long prd);
mutex_unlock(&atmel_pwm->isr_lock);
atmel_pwm_writel(atmel_pwm, PWM_DIS, 1 << pwm->hwpwm);
+ /*
+ * Wait for the PWM channel disable operation to be effective before
+ * stopping the clock.
+ */
+ timeout = jiffies + 2 * HZ;
+
+ while ((atmel_pwm_readl(atmel_pwm, PWM_SR) & (1 << pwm->hwpwm)) &&
+ time_before(jiffies, timeout))
+ usleep_range(10, 100);
+
clk_disable(atmel_pwm->clk);
}
static inline const struct atmel_pwm_data *
atmel_pwm_get_driver_data(struct platform_device *pdev)
{
- if (pdev->dev.of_node) {
- const struct of_device_id *match;
-
- match = of_match_device(atmel_pwm_dt_ids, &pdev->dev);
- if (!match)
- return NULL;
+ const struct platform_device_id *id;
- return match->data;
- } else {
- const struct platform_device_id *id;
+ if (pdev->dev.of_node)
+ return of_device_get_match_data(&pdev->dev);
- id = platform_get_device_id(pdev);
+ id = platform_get_device_id(pdev);
- return (struct atmel_pwm_data *)id->driver_data;
- }
+ return (struct atmel_pwm_data *)id->driver_data;
}
static int atmel_pwm_probe(struct platform_device *pdev)
--- /dev/null
+/*
+ * Copyright (C) 2016 Broadcom
+ *
+ * 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 version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+#define IPROC_PWM_CTRL_OFFSET 0x00
+#define IPROC_PWM_CTRL_TYPE_SHIFT(ch) (15 + (ch))
+#define IPROC_PWM_CTRL_POLARITY_SHIFT(ch) (8 + (ch))
+#define IPROC_PWM_CTRL_EN_SHIFT(ch) (ch)
+
+#define IPROC_PWM_PERIOD_OFFSET(ch) (0x04 + ((ch) << 3))
+#define IPROC_PWM_PERIOD_MIN 0x02
+#define IPROC_PWM_PERIOD_MAX 0xffff
+
+#define IPROC_PWM_DUTY_CYCLE_OFFSET(ch) (0x08 + ((ch) << 3))
+#define IPROC_PWM_DUTY_CYCLE_MIN 0x00
+#define IPROC_PWM_DUTY_CYCLE_MAX 0xffff
+
+#define IPROC_PWM_PRESCALE_OFFSET 0x24
+#define IPROC_PWM_PRESCALE_BITS 0x06
+#define IPROC_PWM_PRESCALE_SHIFT(ch) ((3 - (ch)) * \
+ IPROC_PWM_PRESCALE_BITS)
+#define IPROC_PWM_PRESCALE_MASK(ch) (IPROC_PWM_PRESCALE_MAX << \
+ IPROC_PWM_PRESCALE_SHIFT(ch))
+#define IPROC_PWM_PRESCALE_MIN 0x00
+#define IPROC_PWM_PRESCALE_MAX 0x3f
+
+struct iproc_pwmc {
+ struct pwm_chip chip;
+ void __iomem *base;
+ struct clk *clk;
+};
+
+static inline struct iproc_pwmc *to_iproc_pwmc(struct pwm_chip *chip)
+{
+ return container_of(chip, struct iproc_pwmc, chip);
+}
+
+static void iproc_pwmc_enable(struct iproc_pwmc *ip, unsigned int channel)
+{
+ u32 value;
+
+ value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
+ value |= 1 << IPROC_PWM_CTRL_EN_SHIFT(channel);
+ writel(value, ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ /* must be a 400 ns delay between clearing and setting enable bit */
+ ndelay(400);
+}
+
+static void iproc_pwmc_disable(struct iproc_pwmc *ip, unsigned int channel)
+{
+ u32 value;
+
+ value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
+ value &= ~(1 << IPROC_PWM_CTRL_EN_SHIFT(channel));
+ writel(value, ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ /* must be a 400 ns delay between clearing and setting enable bit */
+ ndelay(400);
+}
+
+static void iproc_pwmc_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct iproc_pwmc *ip = to_iproc_pwmc(chip);
+ u64 tmp, multi, rate;
+ u32 value, prescale;
+
+ rate = clk_get_rate(ip->clk);
+
+ value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ if (value & BIT(IPROC_PWM_CTRL_EN_SHIFT(pwm->hwpwm)))
+ state->enabled = true;
+ else
+ state->enabled = false;
+
+ if (value & BIT(IPROC_PWM_CTRL_POLARITY_SHIFT(pwm->hwpwm)))
+ state->polarity = PWM_POLARITY_NORMAL;
+ else
+ state->polarity = PWM_POLARITY_INVERSED;
+
+ value = readl(ip->base + IPROC_PWM_PRESCALE_OFFSET);
+ prescale = value >> IPROC_PWM_PRESCALE_SHIFT(pwm->hwpwm);
+ prescale &= IPROC_PWM_PRESCALE_MAX;
+
+ multi = NSEC_PER_SEC * (prescale + 1);
+
+ value = readl(ip->base + IPROC_PWM_PERIOD_OFFSET(pwm->hwpwm));
+ tmp = (value & IPROC_PWM_PERIOD_MAX) * multi;
+ state->period = div64_u64(tmp, rate);
+
+ value = readl(ip->base + IPROC_PWM_DUTY_CYCLE_OFFSET(pwm->hwpwm));
+ tmp = (value & IPROC_PWM_PERIOD_MAX) * multi;
+ state->duty_cycle = div64_u64(tmp, rate);
+}
+
+static int iproc_pwmc_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ unsigned long prescale = IPROC_PWM_PRESCALE_MIN;
+ struct iproc_pwmc *ip = to_iproc_pwmc(chip);
+ u32 value, period, duty;
+ u64 rate;
+
+ rate = clk_get_rate(ip->clk);
+
+ /*
+ * Find period count, duty count and prescale to suit duty_cycle and
+ * period. This is done according to formulas described below:
+ *
+ * period_ns = 10^9 * (PRESCALE + 1) * PC / PWM_CLK_RATE
+ * duty_ns = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE
+ *
+ * PC = (PWM_CLK_RATE * period_ns) / (10^9 * (PRESCALE + 1))
+ * DC = (PWM_CLK_RATE * duty_ns) / (10^9 * (PRESCALE + 1))
+ */
+ while (1) {
+ u64 value, div;
+
+ div = NSEC_PER_SEC * (prescale + 1);
+ value = rate * state->period;
+ period = div64_u64(value, div);
+ value = rate * state->duty_cycle;
+ duty = div64_u64(value, div);
+
+ if (period < IPROC_PWM_PERIOD_MIN ||
+ duty < IPROC_PWM_DUTY_CYCLE_MIN)
+ return -EINVAL;
+
+ if (period <= IPROC_PWM_PERIOD_MAX &&
+ duty <= IPROC_PWM_DUTY_CYCLE_MAX)
+ break;
+
+ /* Otherwise, increase prescale and recalculate counts */
+ if (++prescale > IPROC_PWM_PRESCALE_MAX)
+ return -EINVAL;
+ }
+
+ iproc_pwmc_disable(ip, pwm->hwpwm);
+
+ /* Set prescale */
+ value = readl(ip->base + IPROC_PWM_PRESCALE_OFFSET);
+ value &= ~IPROC_PWM_PRESCALE_MASK(pwm->hwpwm);
+ value |= prescale << IPROC_PWM_PRESCALE_SHIFT(pwm->hwpwm);
+ writel(value, ip->base + IPROC_PWM_PRESCALE_OFFSET);
+
+ /* set period and duty cycle */
+ writel(period, ip->base + IPROC_PWM_PERIOD_OFFSET(pwm->hwpwm));
+ writel(duty, ip->base + IPROC_PWM_DUTY_CYCLE_OFFSET(pwm->hwpwm));
+
+ /* set polarity */
+ value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ if (state->polarity == PWM_POLARITY_NORMAL)
+ value |= 1 << IPROC_PWM_CTRL_POLARITY_SHIFT(pwm->hwpwm);
+ else
+ value &= ~(1 << IPROC_PWM_CTRL_POLARITY_SHIFT(pwm->hwpwm));
+
+ writel(value, ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ if (state->enabled)
+ iproc_pwmc_enable(ip, pwm->hwpwm);
+
+ return 0;
+}
+
+static const struct pwm_ops iproc_pwm_ops = {
+ .apply = iproc_pwmc_apply,
+ .get_state = iproc_pwmc_get_state,
+};
+
+static int iproc_pwmc_probe(struct platform_device *pdev)
+{
+ struct iproc_pwmc *ip;
+ struct resource *res;
+ unsigned int i;
+ u32 value;
+ int ret;
+
+ ip = devm_kzalloc(&pdev->dev, sizeof(*ip), GFP_KERNEL);
+ if (!ip)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ip);
+
+ ip->chip.dev = &pdev->dev;
+ ip->chip.ops = &iproc_pwm_ops;
+ ip->chip.base = -1;
+ ip->chip.npwm = 4;
+ ip->chip.of_xlate = of_pwm_xlate_with_flags;
+ ip->chip.of_pwm_n_cells = 3;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ip->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(ip->base))
+ return PTR_ERR(ip->base);
+
+ ip->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(ip->clk)) {
+ dev_err(&pdev->dev, "failed to get clock: %ld\n",
+ PTR_ERR(ip->clk));
+ return PTR_ERR(ip->clk);
+ }
+
+ ret = clk_prepare_enable(ip->clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to enable clock: %d\n", ret);
+ return ret;
+ }
+
+ /* Set full drive and normal polarity for all channels */
+ value = readl(ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ for (i = 0; i < ip->chip.npwm; i++) {
+ value &= ~(1 << IPROC_PWM_CTRL_TYPE_SHIFT(i));
+ value |= 1 << IPROC_PWM_CTRL_POLARITY_SHIFT(i);
+ }
+
+ writel(value, ip->base + IPROC_PWM_CTRL_OFFSET);
+
+ ret = pwmchip_add(&ip->chip);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to add PWM chip: %d\n", ret);
+ clk_disable_unprepare(ip->clk);
+ }
+
+ return ret;
+}
+
+static int iproc_pwmc_remove(struct platform_device *pdev)
+{
+ struct iproc_pwmc *ip = platform_get_drvdata(pdev);
+
+ clk_disable_unprepare(ip->clk);
+
+ return pwmchip_remove(&ip->chip);
+}
+
+static const struct of_device_id bcm_iproc_pwmc_dt[] = {
+ { .compatible = "brcm,iproc-pwm" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, bcm_iproc_pwmc_dt);
+
+static struct platform_driver iproc_pwmc_driver = {
+ .driver = {
+ .name = "bcm-iproc-pwm",
+ .of_match_table = bcm_iproc_pwmc_dt,
+ },
+ .probe = iproc_pwmc_probe,
+ .remove = iproc_pwmc_remove,
+};
+module_platform_driver(iproc_pwmc_driver);
+
+MODULE_AUTHOR("Yendapally Reddy Dhananjaya Reddy <yendapally.reddy@broadcom.com>");
+MODULE_DESCRIPTION("Broadcom iProc PWM driver");
+MODULE_LICENSE("GPL v2");
--- /dev/null
+/*
+ * Copyright (C) 2016 Google, Inc
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2, as published by
+ * the Free Software Foundation.
+ *
+ * Expose a PWM controlled by the ChromeOS EC to the host processor.
+ */
+
+#include <linux/module.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+/**
+ * struct cros_ec_pwm_device - Driver data for EC PWM
+ *
+ * @dev: Device node
+ * @ec: Pointer to EC device
+ * @chip: PWM controller chip
+ */
+struct cros_ec_pwm_device {
+ struct device *dev;
+ struct cros_ec_device *ec;
+ struct pwm_chip chip;
+};
+
+static inline struct cros_ec_pwm_device *pwm_to_cros_ec_pwm(struct pwm_chip *c)
+{
+ return container_of(c, struct cros_ec_pwm_device, chip);
+}
+
+static int cros_ec_pwm_set_duty(struct cros_ec_device *ec, u8 index, u16 duty)
+{
+ struct {
+ struct cros_ec_command msg;
+ struct ec_params_pwm_set_duty params;
+ } buf;
+ struct ec_params_pwm_set_duty *params = &buf.params;
+ struct cros_ec_command *msg = &buf.msg;
+
+ memset(&buf, 0, sizeof(buf));
+
+ msg->version = 0;
+ msg->command = EC_CMD_PWM_SET_DUTY;
+ msg->insize = 0;
+ msg->outsize = sizeof(*params);
+
+ params->duty = duty;
+ params->pwm_type = EC_PWM_TYPE_GENERIC;
+ params->index = index;
+
+ return cros_ec_cmd_xfer_status(ec, msg);
+}
+
+static int __cros_ec_pwm_get_duty(struct cros_ec_device *ec, u8 index,
+ u32 *result)
+{
+ struct {
+ struct cros_ec_command msg;
+ union {
+ struct ec_params_pwm_get_duty params;
+ struct ec_response_pwm_get_duty resp;
+ };
+ } buf;
+ struct ec_params_pwm_get_duty *params = &buf.params;
+ struct ec_response_pwm_get_duty *resp = &buf.resp;
+ struct cros_ec_command *msg = &buf.msg;
+ int ret;
+
+ memset(&buf, 0, sizeof(buf));
+
+ msg->version = 0;
+ msg->command = EC_CMD_PWM_GET_DUTY;
+ msg->insize = sizeof(*params);
+ msg->outsize = sizeof(*resp);
+
+ params->pwm_type = EC_PWM_TYPE_GENERIC;
+ params->index = index;
+
+ ret = cros_ec_cmd_xfer_status(ec, msg);
+ if (result)
+ *result = msg->result;
+ if (ret < 0)
+ return ret;
+
+ return resp->duty;
+}
+
+static int cros_ec_pwm_get_duty(struct cros_ec_device *ec, u8 index)
+{
+ return __cros_ec_pwm_get_duty(ec, index, NULL);
+}
+
+static int cros_ec_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct cros_ec_pwm_device *ec_pwm = pwm_to_cros_ec_pwm(chip);
+ int duty_cycle;
+
+ /* The EC won't let us change the period */
+ if (state->period != EC_PWM_MAX_DUTY)
+ return -EINVAL;
+
+ /*
+ * EC doesn't separate the concept of duty cycle and enabled, but
+ * kernel does. Translate.
+ */
+ duty_cycle = state->enabled ? state->duty_cycle : 0;
+
+ return cros_ec_pwm_set_duty(ec_pwm->ec, pwm->hwpwm, duty_cycle);
+}
+
+static void cros_ec_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct cros_ec_pwm_device *ec_pwm = pwm_to_cros_ec_pwm(chip);
+ int ret;
+
+ ret = cros_ec_pwm_get_duty(ec_pwm->ec, pwm->hwpwm);
+ if (ret < 0) {
+ dev_err(chip->dev, "error getting initial duty: %d\n", ret);
+ return;
+ }
+
+ state->enabled = (ret > 0);
+ state->period = EC_PWM_MAX_DUTY;
+
+ /* Note that "disabled" and "duty cycle == 0" are treated the same */
+ state->duty_cycle = ret;
+}
+
+static struct pwm_device *
+cros_ec_pwm_xlate(struct pwm_chip *pc, const struct of_phandle_args *args)
+{
+ struct pwm_device *pwm;
+
+ if (args->args[0] >= pc->npwm)
+ return ERR_PTR(-EINVAL);
+
+ pwm = pwm_request_from_chip(pc, args->args[0], NULL);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ /* The EC won't let us change the period */
+ pwm->args.period = EC_PWM_MAX_DUTY;
+
+ return pwm;
+}
+
+static const struct pwm_ops cros_ec_pwm_ops = {
+ .get_state = cros_ec_pwm_get_state,
+ .apply = cros_ec_pwm_apply,
+ .owner = THIS_MODULE,
+};
+
+static int cros_ec_num_pwms(struct cros_ec_device *ec)
+{
+ int i, ret;
+
+ /* The index field is only 8 bits */
+ for (i = 0; i <= U8_MAX; i++) {
+ u32 result = 0;
+
+ ret = __cros_ec_pwm_get_duty(ec, i, &result);
+ /* We want to parse EC protocol errors */
+ if (ret < 0 && !(ret == -EPROTO && result))
+ return ret;
+
+ /*
+ * We look for SUCCESS, INVALID_COMMAND, or INVALID_PARAM
+ * responses; everything else is treated as an error.
+ */
+ if (result == EC_RES_INVALID_COMMAND)
+ return -ENODEV;
+ else if (result == EC_RES_INVALID_PARAM)
+ return i;
+ else if (result)
+ return -EPROTO;
+ }
+
+ return U8_MAX;
+}
+
+static int cros_ec_pwm_probe(struct platform_device *pdev)
+{
+ struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
+ struct device *dev = &pdev->dev;
+ struct cros_ec_pwm_device *ec_pwm;
+ struct pwm_chip *chip;
+ int ret;
+
+ if (!ec) {
+ dev_err(dev, "no parent EC device\n");
+ return -EINVAL;
+ }
+
+ ec_pwm = devm_kzalloc(dev, sizeof(*ec_pwm), GFP_KERNEL);
+ if (!ec_pwm)
+ return -ENOMEM;
+ chip = &ec_pwm->chip;
+ ec_pwm->ec = ec;
+
+ /* PWM chip */
+ chip->dev = dev;
+ chip->ops = &cros_ec_pwm_ops;
+ chip->of_xlate = cros_ec_pwm_xlate;
+ chip->of_pwm_n_cells = 1;
+ chip->base = -1;
+ ret = cros_ec_num_pwms(ec);
+ if (ret < 0) {
+ dev_err(dev, "Couldn't find PWMs: %d\n", ret);
+ return ret;
+ }
+ chip->npwm = ret;
+ dev_dbg(dev, "Probed %u PWMs\n", chip->npwm);
+
+ ret = pwmchip_add(chip);
+ if (ret < 0) {
+ dev_err(dev, "cannot register PWM: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, ec_pwm);
+
+ return ret;
+}
+
+static int cros_ec_pwm_remove(struct platform_device *dev)
+{
+ struct cros_ec_pwm_device *ec_pwm = platform_get_drvdata(dev);
+ struct pwm_chip *chip = &ec_pwm->chip;
+
+ return pwmchip_remove(chip);
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id cros_ec_pwm_of_match[] = {
+ { .compatible = "google,cros-ec-pwm" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, cros_ec_pwm_of_match);
+#endif
+
+static struct platform_driver cros_ec_pwm_driver = {
+ .probe = cros_ec_pwm_probe,
+ .remove = cros_ec_pwm_remove,
+ .driver = {
+ .name = "cros-ec-pwm",
+ .of_match_table = of_match_ptr(cros_ec_pwm_of_match),
+ },
+};
+module_platform_driver(cros_ec_pwm_driver);
+
+MODULE_ALIAS("platform:cros-ec-pwm");
+MODULE_DESCRIPTION("ChromeOS EC PWM driver");
+MODULE_LICENSE("GPL v2");
};
#define PWM_ENABLE BIT(31)
+#define PWM_PIN_LEVEL BIT(30)
#define to_lpc32xx_pwm_chip(_chip) \
container_of(_chip, struct lpc32xx_pwm_chip, chip)
struct lpc32xx_pwm_chip *lpc32xx;
struct resource *res;
int ret;
+ u32 val;
lpc32xx = devm_kzalloc(&pdev->dev, sizeof(*lpc32xx), GFP_KERNEL);
if (!lpc32xx)
return ret;
}
+ /* When PWM is disable, configure the output to the default value */
+ val = readl(lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2));
+ val &= ~PWM_PIN_LEVEL;
+ writel(val, lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2));
+
platform_set_drvdata(pdev, lpc32xx);
return 0;
{ PCI_VDEVICE(INTEL, 0x0ac8), (unsigned long)&pwm_lpss_bxt_info},
{ PCI_VDEVICE(INTEL, 0x0f08), (unsigned long)&pwm_lpss_byt_info},
{ PCI_VDEVICE(INTEL, 0x0f09), (unsigned long)&pwm_lpss_byt_info},
+ { PCI_VDEVICE(INTEL, 0x11a5), (unsigned long)&pwm_lpss_bxt_info},
{ PCI_VDEVICE(INTEL, 0x1ac8), (unsigned long)&pwm_lpss_bxt_info},
{ PCI_VDEVICE(INTEL, 0x2288), (unsigned long)&pwm_lpss_bsw_info},
{ PCI_VDEVICE(INTEL, 0x2289), (unsigned long)&pwm_lpss_bsw_info},
#define PWM_SW_UPDATE BIT(30)
#define PWM_BASE_UNIT_SHIFT 8
#define PWM_ON_TIME_DIV_MASK 0x000000ff
-#define PWM_DIVISION_CORRECTION 0x2
/* Size of each PWM register space if multiple */
#define PWM_SIZE 0x400
int duty_ns, int period_ns)
{
struct pwm_lpss_chip *lpwm = to_lpwm(chip);
- u8 on_time_div;
- unsigned long c, base_unit_range;
+ unsigned long long on_time_div;
+ unsigned long c = lpwm->info->clk_rate, base_unit_range;
unsigned long long base_unit, freq = NSEC_PER_SEC;
u32 ctrl;
/*
* The equation is:
- * base_unit = ((freq / c) * base_unit_range) + correction
+ * base_unit = round(base_unit_range * freq / c)
*/
base_unit_range = BIT(lpwm->info->base_unit_bits);
- base_unit = freq * base_unit_range;
+ freq *= base_unit_range;
- c = lpwm->info->clk_rate;
- if (!c)
- return -EINVAL;
-
- do_div(base_unit, c);
- base_unit += PWM_DIVISION_CORRECTION;
+ base_unit = DIV_ROUND_CLOSEST_ULL(freq, c);
if (duty_ns <= 0)
duty_ns = 1;
- on_time_div = 255 - (255 * duty_ns / period_ns);
+ on_time_div = 255ULL * duty_ns;
+ do_div(on_time_div, period_ns);
+ on_time_div = 255ULL - on_time_div;
pm_runtime_get_sync(chip->dev);
const struct pwm_lpss_boardinfo *info)
{
struct pwm_lpss_chip *lpwm;
+ unsigned long c;
int ret;
lpwm = devm_kzalloc(dev, sizeof(*lpwm), GFP_KERNEL);
return ERR_CAST(lpwm->regs);
lpwm->info = info;
+
+ c = lpwm->info->clk_rate;
+ if (!c)
+ return ERR_PTR(-EINVAL);
+
lpwm->chip.dev = dev;
lpwm->chip.ops = &pwm_lpss_ops;
lpwm->chip.base = -1;
struct rockchip_pwm_data {
struct rockchip_pwm_regs regs;
unsigned int prescaler;
+ bool supports_polarity;
const struct pwm_ops *ops;
void (*set_enable)(struct pwm_chip *chip,
- struct pwm_device *pwm, bool enable);
+ struct pwm_device *pwm, bool enable,
+ enum pwm_polarity polarity);
+ void (*get_state)(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state);
};
static inline struct rockchip_pwm_chip *to_rockchip_pwm_chip(struct pwm_chip *c)
}
static void rockchip_pwm_set_enable_v1(struct pwm_chip *chip,
- struct pwm_device *pwm, bool enable)
+ struct pwm_device *pwm, bool enable,
+ enum pwm_polarity polarity)
{
struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
writel_relaxed(val, pc->base + pc->data->regs.ctrl);
}
+static void rockchip_pwm_get_state_v1(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+ u32 enable_conf = PWM_CTRL_OUTPUT_EN | PWM_CTRL_TIMER_EN;
+ u32 val;
+
+ val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+ if ((val & enable_conf) == enable_conf)
+ state->enabled = true;
+}
+
static void rockchip_pwm_set_enable_v2(struct pwm_chip *chip,
- struct pwm_device *pwm, bool enable)
+ struct pwm_device *pwm, bool enable,
+ enum pwm_polarity polarity)
{
struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
PWM_CONTINUOUS;
u32 val;
- if (pwm_get_polarity(pwm) == PWM_POLARITY_INVERSED)
+ if (polarity == PWM_POLARITY_INVERSED)
enable_conf |= PWM_DUTY_NEGATIVE | PWM_INACTIVE_POSITIVE;
else
enable_conf |= PWM_DUTY_POSITIVE | PWM_INACTIVE_NEGATIVE;
writel_relaxed(val, pc->base + pc->data->regs.ctrl);
}
+static void rockchip_pwm_get_state_v2(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+ u32 enable_conf = PWM_OUTPUT_LEFT | PWM_LP_DISABLE | PWM_ENABLE |
+ PWM_CONTINUOUS;
+ u32 val;
+
+ val = readl_relaxed(pc->base + pc->data->regs.ctrl);
+ if ((val & enable_conf) != enable_conf)
+ return;
+
+ state->enabled = true;
+
+ if (!(val & PWM_DUTY_POSITIVE))
+ state->polarity = PWM_POLARITY_INVERSED;
+}
+
+static void rockchip_pwm_get_state(struct pwm_chip *chip,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+ unsigned long clk_rate;
+ u64 tmp;
+ int ret;
+
+ ret = clk_enable(pc->clk);
+ if (ret)
+ return;
+
+ clk_rate = clk_get_rate(pc->clk);
+
+ tmp = readl_relaxed(pc->base + pc->data->regs.period);
+ tmp *= pc->data->prescaler * NSEC_PER_SEC;
+ state->period = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+
+ tmp = readl_relaxed(pc->base + pc->data->regs.duty);
+ tmp *= pc->data->prescaler * NSEC_PER_SEC;
+ state->duty_cycle = DIV_ROUND_CLOSEST_ULL(tmp, clk_rate);
+
+ pc->data->get_state(chip, pwm, state);
+
+ clk_disable(pc->clk);
+}
+
static int rockchip_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
unsigned long period, duty;
u64 clk_rate, div;
- int ret;
clk_rate = clk_get_rate(pc->clk);
* default prescaler value for all practical clock rate values.
*/
div = clk_rate * period_ns;
- do_div(div, pc->data->prescaler * NSEC_PER_SEC);
- period = div;
+ period = DIV_ROUND_CLOSEST_ULL(div,
+ pc->data->prescaler * NSEC_PER_SEC);
div = clk_rate * duty_ns;
- do_div(div, pc->data->prescaler * NSEC_PER_SEC);
- duty = div;
-
- ret = clk_enable(pc->clk);
- if (ret)
- return ret;
+ duty = DIV_ROUND_CLOSEST_ULL(div, pc->data->prescaler * NSEC_PER_SEC);
writel(period, pc->base + pc->data->regs.period);
writel(duty, pc->base + pc->data->regs.duty);
- writel(0, pc->base + pc->data->regs.cntr);
-
- clk_disable(pc->clk);
-
- return 0;
-}
-
-static int rockchip_pwm_set_polarity(struct pwm_chip *chip,
- struct pwm_device *pwm,
- enum pwm_polarity polarity)
-{
- /*
- * No action needed here because pwm->polarity will be set by the core
- * and the core will only change polarity when the PWM is not enabled.
- * We'll handle things in set_enable().
- */
return 0;
}
-static int rockchip_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+static int rockchip_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
{
struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+ struct pwm_state curstate;
+ bool enabled;
int ret;
+ pwm_get_state(pwm, &curstate);
+ enabled = curstate.enabled;
+
ret = clk_enable(pc->clk);
if (ret)
return ret;
- pc->data->set_enable(chip, pwm, true);
+ if (state->polarity != curstate.polarity && enabled) {
+ pc->data->set_enable(chip, pwm, false, state->polarity);
+ enabled = false;
+ }
- return 0;
-}
+ ret = rockchip_pwm_config(chip, pwm, state->duty_cycle, state->period);
+ if (ret) {
+ if (enabled != curstate.enabled)
+ pc->data->set_enable(chip, pwm, !enabled,
+ state->polarity);
-static void rockchip_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct rockchip_pwm_chip *pc = to_rockchip_pwm_chip(chip);
+ goto out;
+ }
+
+ if (state->enabled != enabled)
+ pc->data->set_enable(chip, pwm, state->enabled,
+ state->polarity);
- pc->data->set_enable(chip, pwm, false);
+ /*
+ * Update the state with the real hardware, which can differ a bit
+ * because of period/duty_cycle approximation.
+ */
+ rockchip_pwm_get_state(chip, pwm, state);
+out:
clk_disable(pc->clk);
+
+ return ret;
}
static const struct pwm_ops rockchip_pwm_ops_v1 = {
- .config = rockchip_pwm_config,
- .enable = rockchip_pwm_enable,
- .disable = rockchip_pwm_disable,
+ .get_state = rockchip_pwm_get_state,
+ .apply = rockchip_pwm_apply,
.owner = THIS_MODULE,
};
static const struct pwm_ops rockchip_pwm_ops_v2 = {
- .config = rockchip_pwm_config,
- .set_polarity = rockchip_pwm_set_polarity,
- .enable = rockchip_pwm_enable,
- .disable = rockchip_pwm_disable,
+ .get_state = rockchip_pwm_get_state,
+ .apply = rockchip_pwm_apply,
.owner = THIS_MODULE,
};
.prescaler = 2,
.ops = &rockchip_pwm_ops_v1,
.set_enable = rockchip_pwm_set_enable_v1,
+ .get_state = rockchip_pwm_get_state_v1,
};
static const struct rockchip_pwm_data pwm_data_v2 = {
.ctrl = 0x0c,
},
.prescaler = 1,
+ .supports_polarity = true,
.ops = &rockchip_pwm_ops_v2,
.set_enable = rockchip_pwm_set_enable_v2,
+ .get_state = rockchip_pwm_get_state_v2,
};
static const struct rockchip_pwm_data pwm_data_vop = {
.ctrl = 0x00,
},
.prescaler = 1,
+ .supports_polarity = true,
.ops = &rockchip_pwm_ops_v2,
.set_enable = rockchip_pwm_set_enable_v2,
+ .get_state = rockchip_pwm_get_state_v2,
};
static const struct of_device_id rockchip_pwm_dt_ids[] = {
if (IS_ERR(pc->clk))
return PTR_ERR(pc->clk);
- ret = clk_prepare(pc->clk);
+ ret = clk_prepare_enable(pc->clk);
if (ret)
return ret;
pc->chip.base = -1;
pc->chip.npwm = 1;
- if (pc->data->ops->set_polarity) {
+ if (pc->data->supports_polarity) {
pc->chip.of_xlate = of_pwm_xlate_with_flags;
pc->chip.of_pwm_n_cells = 3;
}
dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
}
+ /* Keep the PWM clk enabled if the PWM appears to be up and running. */
+ if (!pwm_is_enabled(pc->chip.pwms))
+ clk_disable(pc->clk);
+
return ret;
}
{
struct rockchip_pwm_chip *pc = platform_get_drvdata(pdev);
+ /*
+ * Disable the PWM clk before unpreparing it if the PWM device is still
+ * running. This should only happen when the last PWM user left it
+ * enabled, or when nobody requested a PWM that was previously enabled
+ * by the bootloader.
+ *
+ * FIXME: Maybe the core should disable all PWM devices in
+ * pwmchip_remove(). In this case we'd only have to call
+ * clk_unprepare() after pwmchip_remove().
+ *
+ */
+ if (pwm_is_enabled(pc->chip.pwms))
+ clk_disable(pc->clk);
+
clk_unprepare(pc->clk);
return pwmchip_remove(&pc->chip);
--- /dev/null
+/*
+ * Copyright (C) 2016 Linaro Ltd.
+ *
+ * Author: Linus Walleij <linus.walleij@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/bitops.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/mfd/stmpe.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+
+#define STMPE24XX_PWMCS 0x30
+#define PWMCS_EN_PWM0 BIT(0)
+#define PWMCS_EN_PWM1 BIT(1)
+#define PWMCS_EN_PWM2 BIT(2)
+#define STMPE24XX_PWMIC0 0x38
+#define STMPE24XX_PWMIC1 0x39
+#define STMPE24XX_PWMIC2 0x3a
+
+#define STMPE_PWM_24XX_PINBASE 21
+
+struct stmpe_pwm {
+ struct stmpe *stmpe;
+ struct pwm_chip chip;
+ u8 last_duty;
+};
+
+static inline struct stmpe_pwm *to_stmpe_pwm(struct pwm_chip *chip)
+{
+ return container_of(chip, struct stmpe_pwm, chip);
+}
+
+static int stmpe_24xx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct stmpe_pwm *stmpe_pwm = to_stmpe_pwm(chip);
+ u8 value;
+ int ret;
+
+ ret = stmpe_reg_read(stmpe_pwm->stmpe, STMPE24XX_PWMCS);
+ if (ret < 0) {
+ dev_err(chip->dev, "error reading PWM#%u control\n",
+ pwm->hwpwm);
+ return ret;
+ }
+
+ value = ret | BIT(pwm->hwpwm);
+
+ ret = stmpe_reg_write(stmpe_pwm->stmpe, STMPE24XX_PWMCS, value);
+ if (ret) {
+ dev_err(chip->dev, "error writing PWM#%u control\n",
+ pwm->hwpwm);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void stmpe_24xx_pwm_disable(struct pwm_chip *chip,
+ struct pwm_device *pwm)
+{
+ struct stmpe_pwm *stmpe_pwm = to_stmpe_pwm(chip);
+ u8 value;
+ int ret;
+
+ ret = stmpe_reg_read(stmpe_pwm->stmpe, STMPE24XX_PWMCS);
+ if (ret < 0) {
+ dev_err(chip->dev, "error reading PWM#%u control\n",
+ pwm->hwpwm);
+ return;
+ }
+
+ value = ret & ~BIT(pwm->hwpwm);
+
+ ret = stmpe_reg_write(stmpe_pwm->stmpe, STMPE24XX_PWMCS, value);
+ if (ret) {
+ dev_err(chip->dev, "error writing PWM#%u control\n",
+ pwm->hwpwm);
+ return;
+ }
+}
+
+/* STMPE 24xx PWM instructions */
+#define SMAX 0x007f
+#define SMIN 0x00ff
+#define GTS 0x0000
+#define LOAD BIT(14) /* Only available on 2403 */
+#define RAMPUP 0x0000
+#define RAMPDOWN BIT(7)
+#define PRESCALE_512 BIT(14)
+#define STEPTIME_1 BIT(8)
+#define BRANCH (BIT(15) | BIT(13))
+
+static int stmpe_24xx_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct stmpe_pwm *stmpe_pwm = to_stmpe_pwm(chip);
+ unsigned int i, pin;
+ u16 program[3] = {
+ SMAX,
+ GTS,
+ GTS,
+ };
+ u8 offset;
+ int ret;
+
+ /* Make sure we are disabled */
+ if (pwm_is_enabled(pwm)) {
+ stmpe_24xx_pwm_disable(chip, pwm);
+ } else {
+ /* Connect the PWM to the pin */
+ pin = pwm->hwpwm;
+
+ /* On STMPE2401 and 2403 pins 21,22,23 are used */
+ if (stmpe_pwm->stmpe->partnum == STMPE2401 ||
+ stmpe_pwm->stmpe->partnum == STMPE2403)
+ pin += STMPE_PWM_24XX_PINBASE;
+
+ ret = stmpe_set_altfunc(stmpe_pwm->stmpe, BIT(pin),
+ STMPE_BLOCK_PWM);
+ if (ret) {
+ dev_err(chip->dev, "unable to connect PWM#%u to pin\n",
+ pwm->hwpwm);
+ return ret;
+ }
+ }
+
+ /* STMPE24XX */
+ switch (pwm->hwpwm) {
+ case 0:
+ offset = STMPE24XX_PWMIC0;
+ break;
+
+ case 1:
+ offset = STMPE24XX_PWMIC1;
+ break;
+
+ case 2:
+ offset = STMPE24XX_PWMIC1;
+ break;
+
+ default:
+ /* Should not happen as npwm is 3 */
+ return -ENODEV;
+ }
+
+ dev_dbg(chip->dev, "PWM#%u: config duty %d ns, period %d ns\n",
+ pwm->hwpwm, duty_ns, period_ns);
+
+ if (duty_ns == 0) {
+ if (stmpe_pwm->stmpe->partnum == STMPE2401)
+ program[0] = SMAX; /* off all the time */
+
+ if (stmpe_pwm->stmpe->partnum == STMPE2403)
+ program[0] = LOAD | 0xff; /* LOAD 0xff */
+
+ stmpe_pwm->last_duty = 0x00;
+ } else if (duty_ns == period_ns) {
+ if (stmpe_pwm->stmpe->partnum == STMPE2401)
+ program[0] = SMIN; /* on all the time */
+
+ if (stmpe_pwm->stmpe->partnum == STMPE2403)
+ program[0] = LOAD | 0x00; /* LOAD 0x00 */
+
+ stmpe_pwm->last_duty = 0xff;
+ } else {
+ u8 value, last = stmpe_pwm->last_duty;
+ unsigned long duty;
+
+ /*
+ * Counter goes from 0x00 to 0xff repeatedly at 32768 Hz,
+ * (means a period of 30517 ns) then this is compared to the
+ * counter from the ramp, if this is >= PWM counter the output
+ * is high. With LOAD we can define how much of the cycle it
+ * is on.
+ *
+ * Prescale = 0 -> 2 kHz -> T = 1/f = 488281.25 ns
+ */
+
+ /* Scale to 0..0xff */
+ duty = duty_ns * 256;
+ duty = DIV_ROUND_CLOSEST(duty, period_ns);
+ value = duty;
+
+ if (value == last) {
+ /* Run the old program */
+ if (pwm_is_enabled(pwm))
+ stmpe_24xx_pwm_enable(chip, pwm);
+
+ return 0;
+ } else if (stmpe_pwm->stmpe->partnum == STMPE2403) {
+ /* STMPE2403 can simply set the right PWM value */
+ program[0] = LOAD | value;
+ program[1] = 0x0000;
+ } else if (stmpe_pwm->stmpe->partnum == STMPE2401) {
+ /* STMPE2401 need a complex program */
+ u16 incdec = 0x0000;
+
+ if (last < value)
+ /* Count up */
+ incdec = RAMPUP | (value - last);
+ else
+ /* Count down */
+ incdec = RAMPDOWN | (last - value);
+
+ /* Step to desired value, smoothly */
+ program[0] = PRESCALE_512 | STEPTIME_1 | incdec;
+
+ /* Loop eternally to 0x00 */
+ program[1] = BRANCH;
+ }
+
+ dev_dbg(chip->dev,
+ "PWM#%u: value = %02x, last_duty = %02x, program=%04x,%04x,%04x\n",
+ pwm->hwpwm, value, last, program[0], program[1],
+ program[2]);
+ stmpe_pwm->last_duty = value;
+ }
+
+ /*
+ * We can write programs of up to 64 16-bit words into this channel.
+ */
+ for (i = 0; i < ARRAY_SIZE(program); i++) {
+ u8 value;
+
+ value = (program[i] >> 8) & 0xff;
+
+ ret = stmpe_reg_write(stmpe_pwm->stmpe, offset, value);
+ if (ret) {
+ dev_err(chip->dev, "error writing register %02x: %d\n",
+ offset, ret);
+ return ret;
+ }
+
+ value = program[i] & 0xff;
+
+ ret = stmpe_reg_write(stmpe_pwm->stmpe, offset, value);
+ if (ret) {
+ dev_err(chip->dev, "error writing register %02x: %d\n",
+ offset, ret);
+ return ret;
+ }
+ }
+
+ /* If we were enabled, re-enable this PWM */
+ if (pwm_is_enabled(pwm))
+ stmpe_24xx_pwm_enable(chip, pwm);
+
+ /* Sleep for 200ms so we're sure it will take effect */
+ msleep(200);
+
+ dev_dbg(chip->dev, "programmed PWM#%u, %u bytes\n", pwm->hwpwm, i);
+
+ return 0;
+}
+
+static const struct pwm_ops stmpe_24xx_pwm_ops = {
+ .config = stmpe_24xx_pwm_config,
+ .enable = stmpe_24xx_pwm_enable,
+ .disable = stmpe_24xx_pwm_disable,
+ .owner = THIS_MODULE,
+};
+
+static int __init stmpe_pwm_probe(struct platform_device *pdev)
+{
+ struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
+ struct stmpe_pwm *pwm;
+ int ret;
+
+ pwm = devm_kzalloc(&pdev->dev, sizeof(*pwm), GFP_KERNEL);
+ if (!pwm)
+ return -ENOMEM;
+
+ pwm->stmpe = stmpe;
+ pwm->chip.dev = &pdev->dev;
+ pwm->chip.base = -1;
+
+ if (stmpe->partnum == STMPE2401 || stmpe->partnum == STMPE2403) {
+ pwm->chip.ops = &stmpe_24xx_pwm_ops;
+ pwm->chip.npwm = 3;
+ } else {
+ if (stmpe->partnum == STMPE1601)
+ dev_err(&pdev->dev, "STMPE1601 not yet supported\n");
+ else
+ dev_err(&pdev->dev, "Unknown STMPE PWM\n");
+
+ return -ENODEV;
+ }
+
+ ret = stmpe_enable(stmpe, STMPE_BLOCK_PWM);
+ if (ret)
+ return ret;
+
+ ret = pwmchip_add(&pwm->chip);
+ if (ret) {
+ stmpe_disable(stmpe, STMPE_BLOCK_PWM);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, pwm);
+
+ return 0;
+}
+
+static struct platform_driver stmpe_pwm_driver = {
+ .driver = {
+ .name = "stmpe-pwm",
+ },
+};
+builtin_platform_driver_probe(stmpe_pwm_driver, stmpe_pwm_probe);
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/pwm.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
+#include <linux/reset.h>
#define PWM_ENABLE (1 << 31)
#define PWM_DUTY_WIDTH 8
#define PWM_SCALE_WIDTH 13
#define PWM_SCALE_SHIFT 0
-#define NUM_PWM 4
+struct tegra_pwm_soc {
+ unsigned int num_channels;
+};
struct tegra_pwm_chip {
- struct pwm_chip chip;
- struct device *dev;
+ struct pwm_chip chip;
+ struct device *dev;
+
+ struct clk *clk;
+ struct reset_control*rst;
- struct clk *clk;
+ void __iomem *regs;
- void __iomem *mmio_base;
+ const struct tegra_pwm_soc *soc;
};
static inline struct tegra_pwm_chip *to_tegra_pwm_chip(struct pwm_chip *chip)
static inline u32 pwm_readl(struct tegra_pwm_chip *chip, unsigned int num)
{
- return readl(chip->mmio_base + (num << 4));
+ return readl(chip->regs + (num << 4));
}
static inline void pwm_writel(struct tegra_pwm_chip *chip, unsigned int num,
unsigned long val)
{
- writel(val, chip->mmio_base + (num << 4));
+ writel(val, chip->regs + (num << 4));
}
static int tegra_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct tegra_pwm_chip *pc = to_tegra_pwm_chip(chip);
- unsigned long long c;
+ unsigned long long c = duty_ns;
unsigned long rate, hz;
u32 val = 0;
int err;
* per (1 << PWM_DUTY_WIDTH) cycles and make sure to round to the
* nearest integer during division.
*/
- c = duty_ns * ((1 << PWM_DUTY_WIDTH) - 1) + period_ns / 2;
+ c *= (1 << PWM_DUTY_WIDTH);
+ c += period_ns / 2;
do_div(c, period_ns);
val = (u32)c << PWM_DUTY_SHIFT;
if (!pwm)
return -ENOMEM;
+ pwm->soc = of_device_get_match_data(&pdev->dev);
pwm->dev = &pdev->dev;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- pwm->mmio_base = devm_ioremap_resource(&pdev->dev, r);
- if (IS_ERR(pwm->mmio_base))
- return PTR_ERR(pwm->mmio_base);
+ pwm->regs = devm_ioremap_resource(&pdev->dev, r);
+ if (IS_ERR(pwm->regs))
+ return PTR_ERR(pwm->regs);
platform_set_drvdata(pdev, pwm);
if (IS_ERR(pwm->clk))
return PTR_ERR(pwm->clk);
+ pwm->rst = devm_reset_control_get(&pdev->dev, "pwm");
+ if (IS_ERR(pwm->rst)) {
+ ret = PTR_ERR(pwm->rst);
+ dev_err(&pdev->dev, "Reset control is not found: %d\n", ret);
+ return ret;
+ }
+
+ reset_control_deassert(pwm->rst);
+
pwm->chip.dev = &pdev->dev;
pwm->chip.ops = &tegra_pwm_ops;
pwm->chip.base = -1;
- pwm->chip.npwm = NUM_PWM;
+ pwm->chip.npwm = pwm->soc->num_channels;
ret = pwmchip_add(&pwm->chip);
if (ret < 0) {
dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);
+ reset_control_assert(pwm->rst);
return ret;
}
static int tegra_pwm_remove(struct platform_device *pdev)
{
struct tegra_pwm_chip *pc = platform_get_drvdata(pdev);
- int i;
+ unsigned int i;
+ int err;
if (WARN_ON(!pc))
return -ENODEV;
- for (i = 0; i < NUM_PWM; i++) {
+ err = clk_prepare_enable(pc->clk);
+ if (err < 0)
+ return err;
+
+ for (i = 0; i < pc->chip.npwm; i++) {
struct pwm_device *pwm = &pc->chip.pwms[i];
if (!pwm_is_enabled(pwm))
clk_disable_unprepare(pc->clk);
}
+ reset_control_assert(pc->rst);
+ clk_disable_unprepare(pc->clk);
+
return pwmchip_remove(&pc->chip);
}
+static const struct tegra_pwm_soc tegra20_pwm_soc = {
+ .num_channels = 4,
+};
+
+static const struct tegra_pwm_soc tegra186_pwm_soc = {
+ .num_channels = 1,
+};
+
static const struct of_device_id tegra_pwm_of_match[] = {
- { .compatible = "nvidia,tegra20-pwm" },
- { .compatible = "nvidia,tegra30-pwm" },
+ { .compatible = "nvidia,tegra20-pwm", .data = &tegra20_pwm_soc },
+ { .compatible = "nvidia,tegra186-pwm", .data = &tegra186_pwm_soc },
{ }
};
#include <linux/pwm.h>
#include <linux/of_device.h>
-#include "pwm-tipwmss.h"
-
/* ECAP registers and bits definitions */
#define CAP1 0x08
#define CAP2 0x0C
};
static const struct of_device_id ecap_of_match[] = {
+ { .compatible = "ti,am3352-ecap" },
{ .compatible = "ti,am33xx-ecap" },
{},
};
static int ecap_pwm_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
int ret;
struct resource *r;
struct clk *clk;
struct ecap_pwm_chip *pc;
- u16 status;
pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
if (!pc)
return -ENOMEM;
clk = devm_clk_get(&pdev->dev, "fck");
+ if (IS_ERR(clk)) {
+ if (of_device_is_compatible(np, "ti,am33xx-ecap")) {
+ dev_warn(&pdev->dev, "Binding is obsolete.\n");
+ clk = devm_clk_get(pdev->dev.parent, "fck");
+ }
+ }
+
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "failed to get clock\n");
return PTR_ERR(clk);
}
pm_runtime_enable(&pdev->dev);
- pm_runtime_get_sync(&pdev->dev);
-
- status = pwmss_submodule_state_change(pdev->dev.parent,
- PWMSS_ECAPCLK_EN);
- if (!(status & PWMSS_ECAPCLK_EN_ACK)) {
- dev_err(&pdev->dev, "PWMSS config space clock enable failed\n");
- ret = -EINVAL;
- goto pwmss_clk_failure;
- }
-
- pm_runtime_put_sync(&pdev->dev);
platform_set_drvdata(pdev, pc);
return 0;
-
-pwmss_clk_failure:
- pm_runtime_put_sync(&pdev->dev);
- pm_runtime_disable(&pdev->dev);
- pwmchip_remove(&pc->chip);
- return ret;
}
static int ecap_pwm_remove(struct platform_device *pdev)
{
struct ecap_pwm_chip *pc = platform_get_drvdata(pdev);
- pm_runtime_get_sync(&pdev->dev);
- /*
- * Due to hardware misbehaviour, acknowledge of the stop_req
- * is missing. Hence checking of the status bit skipped.
- */
- pwmss_submodule_state_change(pdev->dev.parent, PWMSS_ECAPCLK_STOP_REQ);
- pm_runtime_put_sync(&pdev->dev);
-
pm_runtime_disable(&pdev->dev);
return pwmchip_remove(&pc->chip);
}
#include <linux/pm_runtime.h>
#include <linux/of_device.h>
-#include "pwm-tipwmss.h"
-
/* EHRPWM registers and bits definitions */
/* Time base module registers */
};
static const struct of_device_id ehrpwm_of_match[] = {
+ { .compatible = "ti,am3352-ehrpwm" },
{ .compatible = "ti,am33xx-ehrpwm" },
{},
};
static int ehrpwm_pwm_probe(struct platform_device *pdev)
{
+ struct device_node *np = pdev->dev.of_node;
int ret;
struct resource *r;
struct clk *clk;
struct ehrpwm_pwm_chip *pc;
- u16 status;
pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL);
if (!pc)
return -ENOMEM;
clk = devm_clk_get(&pdev->dev, "fck");
+ if (IS_ERR(clk)) {
+ if (of_device_is_compatible(np, "ti,am33xx-ecap")) {
+ dev_warn(&pdev->dev, "Binding is obsolete.\n");
+ clk = devm_clk_get(pdev->dev.parent, "fck");
+ }
+ }
+
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "failed to get clock\n");
return PTR_ERR(clk);
}
pm_runtime_enable(&pdev->dev);
- pm_runtime_get_sync(&pdev->dev);
-
- status = pwmss_submodule_state_change(pdev->dev.parent,
- PWMSS_EPWMCLK_EN);
- if (!(status & PWMSS_EPWMCLK_EN_ACK)) {
- dev_err(&pdev->dev, "PWMSS config space clock enable failed\n");
- ret = -EINVAL;
- goto pwmss_clk_failure;
- }
-
- pm_runtime_put_sync(&pdev->dev);
platform_set_drvdata(pdev, pc);
return 0;
-
-pwmss_clk_failure:
- pm_runtime_put_sync(&pdev->dev);
- pm_runtime_disable(&pdev->dev);
- pwmchip_remove(&pc->chip);
- clk_unprepare(pc->tbclk);
- return ret;
}
static int ehrpwm_pwm_remove(struct platform_device *pdev)
clk_unprepare(pc->tbclk);
- pm_runtime_get_sync(&pdev->dev);
- /*
- * Due to hardware misbehaviour, acknowledge of the stop_req
- * is missing. Hence checking of the status bit skipped.
- */
- pwmss_submodule_state_change(pdev->dev.parent, PWMSS_EPWMCLK_STOP_REQ);
- pm_runtime_put_sync(&pdev->dev);
-
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
return pwmchip_remove(&pc->chip);
#include <linux/pm_runtime.h>
#include <linux/of_device.h>
-#include "pwm-tipwmss.h"
-
-#define PWMSS_CLKCONFIG 0x8 /* Clock gating reg */
-#define PWMSS_CLKSTATUS 0xc /* Clock gating status reg */
-
-struct pwmss_info {
- void __iomem *mmio_base;
- struct mutex pwmss_lock;
- u16 pwmss_clkconfig;
-};
-
-u16 pwmss_submodule_state_change(struct device *dev, int set)
-{
- struct pwmss_info *info = dev_get_drvdata(dev);
- u16 val;
-
- mutex_lock(&info->pwmss_lock);
- val = readw(info->mmio_base + PWMSS_CLKCONFIG);
- val |= set;
- writew(val , info->mmio_base + PWMSS_CLKCONFIG);
- mutex_unlock(&info->pwmss_lock);
-
- return readw(info->mmio_base + PWMSS_CLKSTATUS);
-}
-EXPORT_SYMBOL(pwmss_submodule_state_change);
-
static const struct of_device_id pwmss_of_match[] = {
{ .compatible = "ti,am33xx-pwmss" },
{},
static int pwmss_probe(struct platform_device *pdev)
{
int ret;
- struct resource *r;
- struct pwmss_info *info;
struct device_node *node = pdev->dev.of_node;
- info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
- if (!info)
- return -ENOMEM;
-
- mutex_init(&info->pwmss_lock);
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- info->mmio_base = devm_ioremap_resource(&pdev->dev, r);
- if (IS_ERR(info->mmio_base))
- return PTR_ERR(info->mmio_base);
-
pm_runtime_enable(&pdev->dev);
pm_runtime_get_sync(&pdev->dev);
- platform_set_drvdata(pdev, info);
/* Populate all the child nodes here... */
ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
static int pwmss_remove(struct platform_device *pdev)
{
- struct pwmss_info *info = platform_get_drvdata(pdev);
-
pm_runtime_put_sync(&pdev->dev);
pm_runtime_disable(&pdev->dev);
- mutex_destroy(&info->pwmss_lock);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int pwmss_suspend(struct device *dev)
{
- struct pwmss_info *info = dev_get_drvdata(dev);
-
- info->pwmss_clkconfig = readw(info->mmio_base + PWMSS_CLKCONFIG);
pm_runtime_put_sync(dev);
return 0;
}
static int pwmss_resume(struct device *dev)
{
- struct pwmss_info *info = dev_get_drvdata(dev);
-
pm_runtime_get_sync(dev);
- writew(info->pwmss_clkconfig, info->mmio_base + PWMSS_CLKCONFIG);
return 0;
}
#endif
+++ /dev/null
-/*
- * TI PWM Subsystem driver
- *
- * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
- *
- * 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.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- */
-
-#ifndef __TIPWMSS_H
-#define __TIPWMSS_H
-
-/* PWM substem clock gating */
-#define PWMSS_ECAPCLK_EN BIT(0)
-#define PWMSS_ECAPCLK_STOP_REQ BIT(1)
-#define PWMSS_EPWMCLK_EN BIT(8)
-#define PWMSS_EPWMCLK_STOP_REQ BIT(9)
-
-#define PWMSS_ECAPCLK_EN_ACK BIT(0)
-#define PWMSS_EPWMCLK_EN_ACK BIT(8)
-
-#ifdef CONFIG_PWM_TIPWMSS
-extern u16 pwmss_submodule_state_change(struct device *dev, int set);
-#else
-static inline u16 pwmss_submodule_state_change(struct device *dev, int set)
-{
- /* return success status value */
- return 0xFFFF;
-}
-#endif
-#endif /* __TIPWMSS_H */
goto unlock;
}
- pwm_apply_state(pwm, &state);
+ ret = pwm_apply_state(pwm, &state);
unlock:
mutex_unlock(&export->lock);
return ret ? : size;
}
+static ssize_t capture_show(struct device *child,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct pwm_device *pwm = child_to_pwm_device(child);
+ struct pwm_capture result;
+ int ret;
+
+ ret = pwm_capture(pwm, &result, jiffies_to_msecs(HZ));
+ if (ret)
+ return ret;
+
+ return sprintf(buf, "%u %u\n", result.period, result.duty_cycle);
+}
+
static DEVICE_ATTR_RW(period);
static DEVICE_ATTR_RW(duty_cycle);
static DEVICE_ATTR_RW(enable);
static DEVICE_ATTR_RW(polarity);
+static DEVICE_ATTR_RO(capture);
static struct attribute *pwm_attrs[] = {
&dev_attr_period.attr,
&dev_attr_duty_cycle.attr,
&dev_attr_enable.attr,
&dev_attr_polarity.attr,
+ &dev_attr_capture.attr,
NULL
};
ATTRIBUTE_GROUPS(pwm);
int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
struct cros_ec_command *msg);
+/**
+ * cros_ec_cmd_xfer_status - Send a command to the ChromeOS EC
+ *
+ * This function is identical to cros_ec_cmd_xfer, except it returns success
+ * status only if both the command was transmitted successfully and the EC
+ * replied with success status. It's not necessary to check msg->result when
+ * using this function.
+ *
+ * @ec_dev: EC device
+ * @msg: Message to write
+ * @return: Num. of bytes transferred on success, <0 on failure
+ */
+int cros_ec_cmd_xfer_status(struct cros_ec_device *ec_dev,
+ struct cros_ec_command *msg);
+
/**
* cros_ec_remove - Remove a ChromeOS EC
*
uint32_t percent;
} __packed;
+#define EC_CMD_PWM_SET_DUTY 0x25
+/* 16 bit duty cycle, 0xffff = 100% */
+#define EC_PWM_MAX_DUTY 0xffff
+
+enum ec_pwm_type {
+ /* All types, indexed by board-specific enum pwm_channel */
+ EC_PWM_TYPE_GENERIC = 0,
+ /* Keyboard backlight */
+ EC_PWM_TYPE_KB_LIGHT,
+ /* Display backlight */
+ EC_PWM_TYPE_DISPLAY_LIGHT,
+ EC_PWM_TYPE_COUNT,
+};
+
+struct ec_params_pwm_set_duty {
+ uint16_t duty; /* Duty cycle, EC_PWM_MAX_DUTY = 100% */
+ uint8_t pwm_type; /* ec_pwm_type */
+ uint8_t index; /* Type-specific index, or 0 if unique */
+} __packed;
+
+#define EC_CMD_PWM_GET_DUTY 0x26
+
+struct ec_params_pwm_get_duty {
+ uint8_t pwm_type; /* ec_pwm_type */
+ uint8_t index; /* Type-specific index, or 0 if unique */
+} __packed;
+
+struct ec_response_pwm_get_duty {
+ uint16_t duty; /* Duty cycle, EC_PWM_MAX_DUTY = 100% */
+} __packed;
+
/*****************************************************************************/
/*
* Lightbar commands. This looks worse than it is. Since we only use one HOST
#include <linux/mutex.h>
#include <linux/of.h>
+struct pwm_capture;
struct seq_file;
+
struct pwm_chip;
/**
* @free: optional hook for freeing a PWM
* @config: configure duty cycles and period length for this PWM
* @set_polarity: configure the polarity of this PWM
+ * @capture: capture and report PWM signal
* @enable: enable PWM output toggling
* @disable: disable PWM output toggling
* @apply: atomically apply a new PWM config. The state argument
int duty_ns, int period_ns);
int (*set_polarity)(struct pwm_chip *chip, struct pwm_device *pwm,
enum pwm_polarity polarity);
+ int (*capture)(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_capture *result, unsigned long timeout);
int (*enable)(struct pwm_chip *chip, struct pwm_device *pwm);
void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm);
int (*apply)(struct pwm_chip *chip, struct pwm_device *pwm,
bool can_sleep;
};
+/**
+ * struct pwm_capture - PWM capture data
+ * @period: period of the PWM signal (in nanoseconds)
+ * @duty_cycle: duty cycle of the PWM signal (in nanoseconds)
+ */
+struct pwm_capture {
+ unsigned int period;
+ unsigned int duty_cycle;
+};
+
#if IS_ENABLED(CONFIG_PWM)
/* PWM user APIs */
struct pwm_device *pwm_request(int pwm_id, const char *label);
if (!pwm)
return -EINVAL;
+ if (duty_ns < 0 || period_ns < 0)
+ return -EINVAL;
+
pwm_get_state(pwm, &state);
if (state.duty_cycle == duty_ns && state.period == period_ns)
return 0;
pwm_apply_state(pwm, &state);
}
-
/* PWM provider APIs */
+int pwm_capture(struct pwm_device *pwm, struct pwm_capture *result,
+ unsigned long timeout);
int pwm_set_chip_data(struct pwm_device *pwm, void *data);
void *pwm_get_chip_data(struct pwm_device *pwm);
return -EINVAL;
}
+static inline int pwm_capture(struct pwm_device *pwm,
+ struct pwm_capture *result,
+ unsigned long timeout)
+{
+ return -EINVAL;
+}
+
static inline int pwm_set_polarity(struct pwm_device *pwm,
enum pwm_polarity polarity)
{
static inline void pwm_apply_args(struct pwm_device *pwm)
{
+ struct pwm_state state = { };
+
/*
* PWM users calling pwm_apply_args() expect to have a fresh config
* where the polarity and period are set according to pwm_args info.
* at startup (even if they are actually enabled), thus authorizing
* polarity setting.
*
- * Instead of setting ->enabled to false, we call pwm_disable()
- * before pwm_set_polarity() to ensure that everything is configured
- * as expected, and the PWM is really disabled when the user request
- * it.
+ * To fulfill this requirement, we apply a new state which disables
+ * the PWM device and set the reference period and polarity config.
*
* Note that PWM users requiring a smooth handover between the
* bootloader and the kernel (like critical regulators controlled by
* PWM devices) will have to switch to the atomic API and avoid calling
* pwm_apply_args().
*/
- pwm_disable(pwm);
- pwm_set_polarity(pwm, pwm->args.polarity);
+
+ state.enabled = false;
+ state.polarity = pwm->args.polarity;
+ state.period = pwm->args.period;
+
+ pwm_apply_state(pwm, &state);
}
struct pwm_lookup {
projects / karo-tx-linux.git / commitdiff