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-rw-r--r--Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt5
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-sifive.txt33
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt9
-rw-r--r--Documentation/devicetree/bindings/pwm/pwm-stm32.txt3
-rw-r--r--Documentation/pwm.txt7
-rw-r--r--drivers/leds/leds-pwm.c45
-rw-r--r--drivers/pwm/Kconfig11
-rw-r--r--drivers/pwm/Makefile1
-rw-r--r--drivers/pwm/core.c172
-rw-r--r--drivers/pwm/pwm-atmel-hlcdc.c1
-rw-r--r--drivers/pwm/pwm-bcm2835.c8
-rw-r--r--drivers/pwm/pwm-fsl-ftm.c383
-rw-r--r--drivers/pwm/pwm-jz4740.c49
-rw-r--r--drivers/pwm/pwm-meson.c386
-rw-r--r--drivers/pwm/pwm-rcar.c39
-rw-r--r--drivers/pwm/pwm-sifive.c339
-rw-r--r--drivers/pwm/pwm-stm32-lp.c25
-rw-r--r--drivers/pwm/pwm-stm32.c2
-rw-r--r--drivers/pwm/sysfs.c102
-rw-r--r--include/linux/pwm.h16
20 files changed, 1154 insertions, 482 deletions
diff --git a/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt b/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt
index 7d9d3f90641b..493bec80d59b 100644
--- a/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt
+++ b/Documentation/devicetree/bindings/pwm/ingenic,jz47xx-pwm.txt
@@ -2,10 +2,7 @@ Ingenic JZ47xx PWM Controller
=============================
Required properties:
-- compatible: One of:
- * "ingenic,jz4740-pwm"
- * "ingenic,jz4770-pwm"
- * "ingenic,jz4780-pwm"
+- compatible: Should be "ingenic,jz4740-pwm"
- #pwm-cells: Should be 3. See pwm.txt in this directory for a description
of the cells format.
- clocks : phandle to the external clock.
diff --git a/Documentation/devicetree/bindings/pwm/pwm-sifive.txt b/Documentation/devicetree/bindings/pwm/pwm-sifive.txt
new file mode 100644
index 000000000000..36447e3c9378
--- /dev/null
+++ b/Documentation/devicetree/bindings/pwm/pwm-sifive.txt
@@ -0,0 +1,33 @@
+SiFive PWM controller
+
+Unlike most other PWM controllers, the SiFive PWM controller currently only
+supports one period for all channels in the PWM. All PWMs need to run at
+the same period. The period also has significant restrictions on the values
+it can achieve, which the driver rounds to the nearest achievable period.
+PWM RTL that corresponds to the IP block version numbers can be found
+here:
+
+https://github.com/sifive/sifive-blocks/tree/master/src/main/scala/devices/pwm
+
+Required properties:
+- compatible: Should be "sifive,<chip>-pwm" and "sifive,pwm<version>".
+ Supported compatible strings are: "sifive,fu540-c000-pwm" for the SiFive
+ PWM v0 as integrated onto the SiFive FU540 chip, and "sifive,pwm0" for the
+ SiFive PWM v0 IP block with no chip integration tweaks.
+ Please refer to sifive-blocks-ip-versioning.txt for details.
+- reg: physical base address and length of the controller's registers
+- clocks: Should contain a clock identifier for the PWM's parent clock.
+- #pwm-cells: Should be 3. See pwm.txt in this directory
+ for a description of the cell format.
+- interrupts: one interrupt per PWM channel
+
+Examples:
+
+pwm: pwm@10020000 {
+ compatible = "sifive,fu540-c000-pwm", "sifive,pwm0";
+ reg = <0x0 0x10020000 0x0 0x1000>;
+ clocks = <&tlclk>;
+ interrupt-parent = <&plic>;
+ interrupts = <42 43 44 45>;
+ #pwm-cells = <3>;
+};
diff --git a/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt b/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt
index bd23302e84be..6521bc44a74e 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-stm32-lp.txt
@@ -11,8 +11,10 @@ Required parameters:
bindings defined in pwm.txt.
Optional properties:
-- pinctrl-names: Set to "default".
-- pinctrl-0: Phandle pointing to pin configuration node for PWM.
+- pinctrl-names: Set to "default". An additional "sleep" state can be
+ defined to set pins in sleep state when in low power.
+- pinctrl-n: Phandle(s) pointing to pin configuration node for PWM,
+ respectively for "default" and "sleep" states.
Example:
timer@40002400 {
@@ -21,7 +23,8 @@ Example:
pwm {
compatible = "st,stm32-pwm-lp";
#pwm-cells = <3>;
- pinctrl-names = "default";
+ pinctrl-names = "default", "sleep";
pinctrl-0 = <&lppwm1_pins>;
+ pinctrl-1 = <&lppwm1_sleep_pins>;
};
};
diff --git a/Documentation/devicetree/bindings/pwm/pwm-stm32.txt b/Documentation/devicetree/bindings/pwm/pwm-stm32.txt
index 3e6d55018d7a..a8690bfa5e1f 100644
--- a/Documentation/devicetree/bindings/pwm/pwm-stm32.txt
+++ b/Documentation/devicetree/bindings/pwm/pwm-stm32.txt
@@ -8,6 +8,8 @@ Required parameters:
- pinctrl-names: Set to "default".
- pinctrl-0: List of phandles pointing to pin configuration nodes for PWM module.
For Pinctrl properties see ../pinctrl/pinctrl-bindings.txt
+- #pwm-cells: Should be set to 3. This PWM chip uses the default 3 cells
+ bindings defined in pwm.txt.
Optional parameters:
- st,breakinput: One or two <index level filter> to describe break input configurations.
@@ -28,6 +30,7 @@ Example:
pwm {
compatible = "st,stm32-pwm";
+ #pwm-cells = <3>;
pinctrl-0 = <&pwm1_pins>;
pinctrl-names = "default";
st,breakinput = <0 1 5>;
diff --git a/Documentation/pwm.txt b/Documentation/pwm.txt
index 8fbf0aa3ba2d..ab62f1bb0366 100644
--- a/Documentation/pwm.txt
+++ b/Documentation/pwm.txt
@@ -65,6 +65,10 @@ period). struct pwm_args contains 2 fields (period and polarity) and should
be used to set the initial PWM config (usually done in the probe function
of the PWM user). PWM arguments are retrieved with pwm_get_args().
+All consumers should really be reconfiguring the PWM upon resume as
+appropriate. This is the only way to ensure that everything is resumed in
+the proper order.
+
Using PWMs with the sysfs interface
-----------------------------------
@@ -141,6 +145,9 @@ The implementation of ->get_state() (a method used to retrieve initial PWM
state) is also encouraged for the same reason: letting the PWM user know
about the current PWM state would allow him to avoid glitches.
+Drivers should not implement any power management. In other words,
+consumers should implement it as described in the "Using PWMs" section.
+
Locking
-------
diff --git a/drivers/leds/leds-pwm.c b/drivers/leds/leds-pwm.c
index 9328193189ba..48d068f80f11 100644
--- a/drivers/leds/leds-pwm.c
+++ b/drivers/leds/leds-pwm.c
@@ -72,7 +72,7 @@ static inline size_t sizeof_pwm_leds_priv(int num_leds)
}
static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
- struct led_pwm *led, struct device_node *child)
+ struct led_pwm *led, struct fwnode_handle *fwnode)
{
struct led_pwm_data *led_data = &priv->leds[priv->num_leds];
struct pwm_args pargs;
@@ -85,8 +85,8 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
led_data->cdev.max_brightness = led->max_brightness;
led_data->cdev.flags = LED_CORE_SUSPENDRESUME;
- if (child)
- led_data->pwm = devm_of_pwm_get(dev, child, NULL);
+ if (fwnode)
+ led_data->pwm = devm_fwnode_pwm_get(dev, fwnode, NULL);
else
led_data->pwm = devm_pwm_get(dev, led->name);
if (IS_ERR(led_data->pwm)) {
@@ -111,7 +111,8 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
if (!led_data->period && (led->pwm_period_ns > 0))
led_data->period = led->pwm_period_ns;
- ret = devm_of_led_classdev_register(dev, child, &led_data->cdev);
+ ret = devm_of_led_classdev_register(dev, to_of_node(fwnode),
+ &led_data->cdev);
if (ret == 0) {
priv->num_leds++;
led_pwm_set(&led_data->cdev, led_data->cdev.brightness);
@@ -123,27 +124,35 @@ static int led_pwm_add(struct device *dev, struct led_pwm_priv *priv,
return ret;
}
-static int led_pwm_create_of(struct device *dev, struct led_pwm_priv *priv)
+static int led_pwm_create_fwnode(struct device *dev, struct led_pwm_priv *priv)
{
- struct device_node *child;
+ struct fwnode_handle *fwnode;
struct led_pwm led;
int ret = 0;
memset(&led, 0, sizeof(led));
- for_each_child_of_node(dev->of_node, child) {
- led.name = of_get_property(child, "label", NULL) ? :
- child->name;
+ device_for_each_child_node(dev, fwnode) {
+ ret = fwnode_property_read_string(fwnode, "label", &led.name);
+ if (ret && is_of_node(fwnode))
+ led.name = to_of_node(fwnode)->name;
- led.default_trigger = of_get_property(child,
- "linux,default-trigger", NULL);
- led.active_low = of_property_read_bool(child, "active-low");
- of_property_read_u32(child, "max-brightness",
- &led.max_brightness);
+ if (!led.name) {
+ fwnode_handle_put(fwnode);
+ return -EINVAL;
+ }
+
+ fwnode_property_read_string(fwnode, "linux,default-trigger",
+ &led.default_trigger);
+
+ led.active_low = fwnode_property_read_bool(fwnode,
+ "active-low");
+ fwnode_property_read_u32(fwnode, "max-brightness",
+ &led.max_brightness);
- ret = led_pwm_add(dev, priv, &led, child);
+ ret = led_pwm_add(dev, priv, &led, fwnode);
if (ret) {
- of_node_put(child);
+ fwnode_handle_put(fwnode);
break;
}
}
@@ -161,7 +170,7 @@ static int led_pwm_probe(struct platform_device *pdev)
if (pdata)
count = pdata->num_leds;
else
- count = of_get_child_count(pdev->dev.of_node);
+ count = device_get_child_node_count(&pdev->dev);
if (!count)
return -EINVAL;
@@ -179,7 +188,7 @@ static int led_pwm_probe(struct platform_device *pdev)
break;
}
} else {
- ret = led_pwm_create_of(&pdev->dev, priv);
+ ret = led_pwm_create_fwnode(&pdev->dev, priv);
}
if (ret)
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index dff5a93f7daa..a7e57516959e 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -401,6 +401,17 @@ config PWM_SAMSUNG
To compile this driver as a module, choose M here: the module
will be called pwm-samsung.
+config PWM_SIFIVE
+ tristate "SiFive PWM support"
+ depends on OF
+ depends on COMMON_CLK
+ depends on RISCV || COMPILE_TEST
+ help
+ Generic PWM framework driver for SiFive SoCs.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-sifive.
+
config PWM_SPEAR
tristate "STMicroelectronics SPEAr PWM support"
depends on PLAT_SPEAR
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index c368599d36c0..76b555b51887 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_PWM_RCAR) += pwm-rcar.o
obj-$(CONFIG_PWM_RENESAS_TPU) += pwm-renesas-tpu.o
obj-$(CONFIG_PWM_ROCKCHIP) += pwm-rockchip.o
obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o
+obj-$(CONFIG_PWM_SIFIVE) += pwm-sifive.o
obj-$(CONFIG_PWM_SPEAR) += pwm-spear.o
obj-$(CONFIG_PWM_STI) += pwm-sti.o
obj-$(CONFIG_PWM_STM32) += pwm-stm32.o
diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index 275b5f399a1a..c3ab07ab31a9 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -6,6 +6,7 @@
* Copyright (C) 2011-2012 Avionic Design GmbH
*/
+#include <linux/acpi.h>
#include <linux/module.h>
#include <linux/pwm.h>
#include <linux/radix-tree.h>
@@ -626,8 +627,35 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np)
return ERR_PTR(-EPROBE_DEFER);
}
+static struct device_link *pwm_device_link_add(struct device *dev,
+ struct pwm_device *pwm)
+{
+ struct device_link *dl;
+
+ if (!dev) {
+ /*
+ * No device for the PWM consumer has been provided. It may
+ * impact the PM sequence ordering: the PWM supplier may get
+ * suspended before the consumer.
+ */
+ dev_warn(pwm->chip->dev,
+ "No consumer device specified to create a link to\n");
+ return NULL;
+ }
+
+ dl = device_link_add(dev, pwm->chip->dev, DL_FLAG_AUTOREMOVE_CONSUMER);
+ if (!dl) {
+ dev_err(dev, "failed to create device link to %s\n",
+ dev_name(pwm->chip->dev));
+ return ERR_PTR(-EINVAL);
+ }
+
+ return dl;
+}
+
/**
* of_pwm_get() - request a PWM via the PWM framework
+ * @dev: device for PWM consumer
* @np: device node to get the PWM from
* @con_id: consumer name
*
@@ -645,10 +673,12 @@ static struct pwm_chip *of_node_to_pwmchip(struct device_node *np)
* Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
* error code on failure.
*/
-struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
+struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np,
+ const char *con_id)
{
struct pwm_device *pwm = NULL;
struct of_phandle_args args;
+ struct device_link *dl;
struct pwm_chip *pc;
int index = 0;
int err;
@@ -679,6 +709,14 @@ struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id)
if (IS_ERR(pwm))
goto put;
+ dl = pwm_device_link_add(dev, pwm);
+ if (IS_ERR(dl)) {
+ /* of_xlate ended up calling pwm_request_from_chip() */
+ pwm_free(pwm);
+ pwm = ERR_CAST(dl);
+ goto put;
+ }
+
/*
* If a consumer name was not given, try to look it up from the
* "pwm-names" property if it exists. Otherwise use the name of
@@ -700,6 +738,85 @@ put:
}
EXPORT_SYMBOL_GPL(of_pwm_get);
+#if IS_ENABLED(CONFIG_ACPI)
+static struct pwm_chip *device_to_pwmchip(struct device *dev)
+{
+ struct pwm_chip *chip;
+
+ mutex_lock(&pwm_lock);
+
+ list_for_each_entry(chip, &pwm_chips, list) {
+ struct acpi_device *adev = ACPI_COMPANION(chip->dev);
+
+ if ((chip->dev == dev) || (adev && &adev->dev == dev)) {
+ mutex_unlock(&pwm_lock);
+ return chip;
+ }
+ }
+
+ mutex_unlock(&pwm_lock);
+
+ return ERR_PTR(-EPROBE_DEFER);
+}
+#endif
+
+/**
+ * acpi_pwm_get() - request a PWM via parsing "pwms" property in ACPI
+ * @fwnode: firmware node to get the "pwm" property from
+ *
+ * Returns the PWM device parsed from the fwnode and index specified in the
+ * "pwms" property or a negative error-code on failure.
+ * Values parsed from the device tree are stored in the returned PWM device
+ * object.
+ *
+ * This is analogous to of_pwm_get() except con_id is not yet supported.
+ * ACPI entries must look like
+ * Package () {"pwms", Package ()
+ * { <PWM device reference>, <PWM index>, <PWM period> [, <PWM flags>]}}
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+static struct pwm_device *acpi_pwm_get(struct fwnode_handle *fwnode)
+{
+ struct pwm_device *pwm = ERR_PTR(-ENODEV);
+#if IS_ENABLED(CONFIG_ACPI)
+ struct fwnode_reference_args args;
+ struct acpi_device *acpi;
+ struct pwm_chip *chip;
+ int ret;
+
+ memset(&args, 0, sizeof(args));
+
+ ret = __acpi_node_get_property_reference(fwnode, "pwms", 0, 3, &args);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ acpi = to_acpi_device_node(args.fwnode);
+ if (!acpi)
+ return ERR_PTR(-EINVAL);
+
+ if (args.nargs < 2)
+ return ERR_PTR(-EPROTO);
+
+ chip = device_to_pwmchip(&acpi->dev);
+ if (IS_ERR(chip))
+ return ERR_CAST(chip);
+
+ pwm = pwm_request_from_chip(chip, args.args[0], NULL);
+ if (IS_ERR(pwm))
+ return pwm;
+
+ pwm->args.period = args.args[1];
+ pwm->args.polarity = PWM_POLARITY_NORMAL;
+
+ if (args.nargs > 2 && args.args[2] & PWM_POLARITY_INVERTED)
+ pwm->args.polarity = PWM_POLARITY_INVERSED;
+#endif
+
+ return pwm;
+}
+
/**
* pwm_add_table() - register PWM device consumers
* @table: array of consumers to register
@@ -754,6 +871,7 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
const char *dev_id = dev ? dev_name(dev) : NULL;
struct pwm_device *pwm;
struct pwm_chip *chip;
+ struct device_link *dl;
unsigned int best = 0;
struct pwm_lookup *p, *chosen = NULL;
unsigned int match;
@@ -761,7 +879,11 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
/* look up via DT first */
if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
- return of_pwm_get(dev->of_node, con_id);
+ return of_pwm_get(dev, dev->of_node, con_id);
+
+ /* then lookup via ACPI */
+ if (dev && is_acpi_node(dev->fwnode))
+ return acpi_pwm_get(dev->fwnode);
/*
* We look up the provider in the static table typically provided by
@@ -838,6 +960,12 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
if (IS_ERR(pwm))
return pwm;
+ dl = pwm_device_link_add(dev, pwm);
+ if (IS_ERR(dl)) {
+ pwm_free(pwm);
+ return ERR_CAST(dl);
+ }
+
pwm->args.period = chosen->period;
pwm->args.polarity = chosen->polarity;
@@ -930,7 +1058,7 @@ struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
if (!ptr)
return ERR_PTR(-ENOMEM);
- pwm = of_pwm_get(np, con_id);
+ pwm = of_pwm_get(dev, np, con_id);
if (!IS_ERR(pwm)) {
*ptr = pwm;
devres_add(dev, ptr);
@@ -942,6 +1070,44 @@ struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
}
EXPORT_SYMBOL_GPL(devm_of_pwm_get);
+/**
+ * devm_fwnode_pwm_get() - request a resource managed PWM from firmware node
+ * @dev: device for PWM consumer
+ * @fwnode: firmware node to get the PWM from
+ * @con_id: consumer name
+ *
+ * Returns the PWM device parsed from the firmware node. See of_pwm_get() and
+ * acpi_pwm_get() for a detailed description.
+ *
+ * Returns: A pointer to the requested PWM device or an ERR_PTR()-encoded
+ * error code on failure.
+ */
+struct pwm_device *devm_fwnode_pwm_get(struct device *dev,
+ struct fwnode_handle *fwnode,
+ const char *con_id)
+{
+ struct pwm_device **ptr, *pwm = ERR_PTR(-ENODEV);
+
+ ptr = devres_alloc(devm_pwm_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ if (is_of_node(fwnode))
+ pwm = of_pwm_get(dev, to_of_node(fwnode), con_id);
+ else if (is_acpi_node(fwnode))
+ pwm = acpi_pwm_get(fwnode);
+
+ if (!IS_ERR(pwm)) {
+ *ptr = pwm;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return pwm;
+}
+EXPORT_SYMBOL_GPL(devm_fwnode_pwm_get);
+
static int devm_pwm_match(struct device *dev, void *res, void *data)
{
struct pwm_device **p = res;
diff --git a/drivers/pwm/pwm-atmel-hlcdc.c b/drivers/pwm/pwm-atmel-hlcdc.c
index 7186db85b15f..d13a83f430ac 100644
--- a/drivers/pwm/pwm-atmel-hlcdc.c
+++ b/drivers/pwm/pwm-atmel-hlcdc.c
@@ -235,6 +235,7 @@ static const struct of_device_id atmel_hlcdc_dt_ids[] = {
.compatible = "atmel,sama5d4-hlcdc",
.data = &atmel_hlcdc_pwm_sama5d3_errata,
},
+ { .compatible = "microchip,sam9x60-hlcdc", },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, atmel_hlcdc_dt_ids);
diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c
index 5652f461d994..f6fe0b922e1e 100644
--- a/drivers/pwm/pwm-bcm2835.c
+++ b/drivers/pwm/pwm-bcm2835.c
@@ -70,7 +70,7 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
}
- scaler = NSEC_PER_SEC / rate;
+ scaler = DIV_ROUND_CLOSEST(NSEC_PER_SEC, rate);
if (period_ns <= MIN_PERIOD) {
dev_err(pc->dev, "period %d not supported, minimum %d\n",
@@ -78,8 +78,10 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
}
- writel(duty_ns / scaler, pc->base + DUTY(pwm->hwpwm));
- writel(period_ns / scaler, pc->base + PERIOD(pwm->hwpwm));
+ writel(DIV_ROUND_CLOSEST(duty_ns, scaler),
+ pc->base + DUTY(pwm->hwpwm));
+ writel(DIV_ROUND_CLOSEST(period_ns, scaler),
+ pc->base + PERIOD(pwm->hwpwm));
return 0;
}
diff --git a/drivers/pwm/pwm-fsl-ftm.c b/drivers/pwm/pwm-fsl-ftm.c
index a39b48839df7..9d31a217111d 100644
--- a/drivers/pwm/pwm-fsl-ftm.c
+++ b/drivers/pwm/pwm-fsl-ftm.c
@@ -34,17 +34,19 @@ struct fsl_ftm_soc {
bool has_enable_bits;
};
+struct fsl_pwm_periodcfg {
+ enum fsl_pwm_clk clk_select;
+ unsigned int clk_ps;
+ unsigned int mod_period;
+};
+
struct fsl_pwm_chip {
struct pwm_chip chip;
-
struct mutex lock;
-
- unsigned int cnt_select;
- unsigned int clk_ps;
-
struct regmap *regmap;
- int period_ns;
+ /* This value is valid iff a pwm is running */
+ struct fsl_pwm_periodcfg period;
struct clk *ipg_clk;
struct clk *clk[FSL_PWM_CLK_MAX];
@@ -57,6 +59,33 @@ static inline struct fsl_pwm_chip *to_fsl_chip(struct pwm_chip *chip)
return container_of(chip, struct fsl_pwm_chip, chip);
}
+static void ftm_clear_write_protection(struct fsl_pwm_chip *fpc)
+{
+ u32 val;
+
+ regmap_read(fpc->regmap, FTM_FMS, &val);
+ if (val & FTM_FMS_WPEN)
+ regmap_update_bits(fpc->regmap, FTM_MODE, FTM_MODE_WPDIS,
+ FTM_MODE_WPDIS);
+}
+
+static void ftm_set_write_protection(struct fsl_pwm_chip *fpc)
+{
+ regmap_update_bits(fpc->regmap, FTM_FMS, FTM_FMS_WPEN, FTM_FMS_WPEN);
+}
+
+static bool fsl_pwm_periodcfg_are_equal(const struct fsl_pwm_periodcfg *a,
+ const struct fsl_pwm_periodcfg *b)
+{
+ if (a->clk_select != b->clk_select)
+ return false;
+ if (a->clk_ps != b->clk_ps)
+ return false;
+ if (a->mod_period != b->mod_period)
+ return false;
+ return true;
+}
+
static int fsl_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
int ret;
@@ -87,89 +116,58 @@ static void fsl_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
clk_disable_unprepare(fpc->ipg_clk);
}
-static int fsl_pwm_calculate_default_ps(struct fsl_pwm_chip *fpc,
- enum fsl_pwm_clk index)
+static unsigned int fsl_pwm_ticks_to_ns(struct fsl_pwm_chip *fpc,
+ unsigned int ticks)
{
- unsigned long sys_rate, cnt_rate;
- unsigned long long ratio;
-
- sys_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_SYS]);
- if (!sys_rate)
- return -EINVAL;
-
- cnt_rate = clk_get_rate(fpc->clk[fpc->cnt_select]);
- if (!cnt_rate)
- return -EINVAL;
-
- switch (index) {
- case FSL_PWM_CLK_SYS:
- fpc->clk_ps = 1;
- break;
- case FSL_PWM_CLK_FIX:
- ratio = 2 * cnt_rate - 1;
- do_div(ratio, sys_rate);
- fpc->clk_ps = ratio;
- break;
- case FSL_PWM_CLK_EXT:
- ratio = 4 * cnt_rate - 1;
- do_div(ratio, sys_rate);
- fpc->clk_ps = ratio;
- break;
- default:
- return -EINVAL;
- }
-
- return 0;
+ unsigned long rate;
+ unsigned long long exval;
+
+ rate = clk_get_rate(fpc->clk[fpc->period.clk_select]);
+ exval = ticks;
+ exval *= 1000000000UL;
+ do_div(exval, rate >> fpc->period.clk_ps);
+ return exval;
}
-static unsigned long fsl_pwm_calculate_cycles(struct fsl_pwm_chip *fpc,
- unsigned long period_ns)
+static bool fsl_pwm_calculate_period_clk(struct fsl_pwm_chip *fpc,
+ unsigned int period_ns,
+ enum fsl_pwm_clk index,
+ struct fsl_pwm_periodcfg *periodcfg
+ )
{
- unsigned long long c, c0;
+ unsigned long long c;
+ unsigned int ps;
- c = clk_get_rate(fpc->clk[fpc->cnt_select]);
+ c = clk_get_rate(fpc->clk[index]);
c = c * period_ns;
do_div(c, 1000000000UL);
- do {
- c0 = c;
- do_div(c0, (1 << fpc->clk_ps));
- if (c0 <= 0xFFFF)
- return (unsigned long)c0;
- } while (++fpc->clk_ps < 8);
-
- return 0;
-}
-
-static unsigned long fsl_pwm_calculate_period_cycles(struct fsl_pwm_chip *fpc,
- unsigned long period_ns,
- enum fsl_pwm_clk index)
-{
- int ret;
+ if (c == 0)
+ return false;
- ret = fsl_pwm_calculate_default_ps(fpc, index);
- if (ret) {
- dev_err(fpc->chip.dev,
- "failed to calculate default prescaler: %d\n",
- ret);
- return 0;
+ for (ps = 0; ps < 8 ; ++ps, c >>= 1) {
+ if (c <= 0x10000) {
+ periodcfg->clk_select = index;
+ periodcfg->clk_ps = ps;
+ periodcfg->mod_period = c - 1;
+ return true;
+ }
}
-
- return fsl_pwm_calculate_cycles(fpc, period_ns);
+ return false;
}
-static unsigned long fsl_pwm_calculate_period(struct fsl_pwm_chip *fpc,
- unsigned long period_ns)
+static bool fsl_pwm_calculate_period(struct fsl_pwm_chip *fpc,
+ unsigned int period_ns,
+ struct fsl_pwm_periodcfg *periodcfg)
{
enum fsl_pwm_clk m0, m1;
- unsigned long fix_rate, ext_rate, cycles;
+ unsigned long fix_rate, ext_rate;
+ bool ret;
- cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns,
- FSL_PWM_CLK_SYS);
- if (cycles) {
- fpc->cnt_select = FSL_PWM_CLK_SYS;
- return cycles;
- }
+ ret = fsl_pwm_calculate_period_clk(fpc, period_ns, FSL_PWM_CLK_SYS,
+ periodcfg);
+ if (ret)
+ return true;
fix_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_FIX]);
ext_rate = clk_get_rate(fpc->clk[FSL_PWM_CLK_EXT]);
@@ -182,158 +180,185 @@ static unsigned long fsl_pwm_calculate_period(struct fsl_pwm_chip *fpc,
m1 = FSL_PWM_CLK_FIX;
}
- cycles = fsl_pwm_calculate_period_cycles(fpc, period_ns, m0);
- if (cycles) {
- fpc->cnt_select = m0;
- return cycles;
- }
-
- fpc->cnt_select = m1;
+ ret = fsl_pwm_calculate_period_clk(fpc, period_ns, m0, periodcfg);
+ if (ret)
+ return true;
- return fsl_pwm_calculate_period_cycles(fpc, period_ns, m1);
+ return fsl_pwm_calculate_period_clk(fpc, period_ns, m1, periodcfg);
}
-static unsigned long fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc,
- unsigned long period_ns,
- unsigned long duty_ns)
+static unsigned int fsl_pwm_calculate_duty(struct fsl_pwm_chip *fpc,
+ unsigned int duty_ns)
{
unsigned long long duty;
- u32 val;
- regmap_read(fpc->regmap, FTM_MOD, &val);
- duty = (unsigned long long)duty_ns * (val + 1);
+ unsigned int period = fpc->period.mod_period + 1;
+ unsigned int period_ns = fsl_pwm_ticks_to_ns(fpc, period);
+
+ duty = (unsigned long long)duty_ns * period;
do_div(duty, period_ns);
- return (unsigned long)duty;
+ return (unsigned int)duty;
}
-static int fsl_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns)
+static bool fsl_pwm_is_any_pwm_enabled(struct fsl_pwm_chip *fpc,
+ struct pwm_device *pwm)
{
- struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
- u32 period, duty;
+ u32 val;
- mutex_lock(&fpc->lock);
+ regmap_read(fpc->regmap, FTM_OUTMASK, &val);
+ if (~val & 0xFF)
+ return true;
+ else
+ return false;
+}
+
+static bool fsl_pwm_is_other_pwm_enabled(struct fsl_pwm_chip *fpc,
+ struct pwm_device *pwm)
+{
+ u32 val;
+ regmap_read(fpc->regmap, FTM_OUTMASK, &val);
+ if (~(val | BIT(pwm->hwpwm)) & 0xFF)
+ return true;
+ else
+ return false;
+}
+
+static int fsl_pwm_apply_config(struct fsl_pwm_chip *fpc,
+ struct pwm_device *pwm,
+ struct pwm_state *newstate)
+{
+ unsigned int duty;
+ u32 reg_polarity;
+
+ struct fsl_pwm_periodcfg periodcfg;
+ bool do_write_period = false;
+
+ if (!fsl_pwm_calculate_period(fpc, newstate->period, &periodcfg)) {
+ dev_err(fpc->chip.dev, "failed to calculate new period\n");
+ return -EINVAL;
+ }
+
+ if (!fsl_pwm_is_any_pwm_enabled(fpc, pwm))
+ do_write_period = true;
/*
* The Freescale FTM controller supports only a single period for
- * all PWM channels, therefore incompatible changes need to be
- * refused.
+ * all PWM channels, therefore verify if the newly computed period
+ * is different than the current period being used. In such case
+ * we allow to change the period only if no other pwm is running.
*/
- if (fpc->period_ns && fpc->period_ns != period_ns) {
- dev_err(fpc->chip.dev,
- "conflicting period requested for PWM %u\n",
- pwm->hwpwm);
- mutex_unlock(&fpc->lock);
- return -EBUSY;
+ else if (!fsl_pwm_periodcfg_are_equal(&fpc->period, &periodcfg)) {
+ if (fsl_pwm_is_other_pwm_enabled(fpc, pwm)) {
+ dev_err(fpc->chip.dev,
+ "Cannot change period for PWM %u, disable other PWMs first\n",
+ pwm->hwpwm);
+ return -EBUSY;
+ }
+ if (fpc->period.clk_select != periodcfg.clk_select) {
+ int ret;
+ enum fsl_pwm_clk oldclk = fpc->period.clk_select;
+ enum fsl_pwm_clk newclk = periodcfg.clk_select;
+
+ ret = clk_prepare_enable(fpc->clk[newclk]);
+ if (ret)
+ return ret;
+ clk_disable_unprepare(fpc->clk[oldclk]);
+ }
+ do_write_period = true;
}
- if (!fpc->period_ns && duty_ns) {
- period = fsl_pwm_calculate_period(fpc, period_ns);
- if (!period) {
- dev_err(fpc->chip.dev, "failed to calculate period\n");
- mutex_unlock(&fpc->lock);
- return -EINVAL;
- }
+ ftm_clear_write_protection(fpc);
+ if (do_write_period) {
+ regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK,
+ FTM_SC_CLK(periodcfg.clk_select));
regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_PS_MASK,
- fpc->clk_ps);
- regmap_write(fpc->regmap, FTM_MOD, period - 1);
+ periodcfg.clk_ps);
+ regmap_write(fpc->regmap, FTM_MOD, periodcfg.mod_period);
- fpc->period_ns = period_ns;
+ fpc->period = periodcfg;
}
- mutex_unlock(&fpc->lock);
-
- duty = fsl_pwm_calculate_duty(fpc, period_ns, duty_ns);
+ duty = fsl_pwm_calculate_duty(fpc, newstate->duty_cycle);
regmap_write(fpc->regmap, FTM_CSC(pwm->hwpwm),
FTM_CSC_MSB | FTM_CSC_ELSB);
regmap_write(fpc->regmap, FTM_CV(pwm->hwpwm), duty);
- return 0;
-}
-
-static int fsl_pwm_set_polarity(struct pwm_chip *chip,
- struct pwm_device *pwm,
- enum pwm_polarity polarity)
-{
- struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
- u32 val;
+ reg_polarity = 0;
+ if (newstate->polarity == PWM_POLARITY_INVERSED)
+ reg_polarity = BIT(pwm->hwpwm);
- regmap_read(fpc->regmap, FTM_POL, &val);
+ regmap_update_bits(fpc->regmap, FTM_POL, BIT(pwm->hwpwm), reg_polarity);
- if (polarity == PWM_POLARITY_INVERSED)
- val |= BIT(pwm->hwpwm);
- else
- val &= ~BIT(pwm->hwpwm);
+ newstate->period = fsl_pwm_ticks_to_ns(fpc,
+ fpc->period.mod_period + 1);
+ newstate->duty_cycle = fsl_pwm_ticks_to_ns(fpc, duty);
- regmap_write(fpc->regmap, FTM_POL, val);
+ ftm_set_write_protection(fpc);
return 0;
}
-static int fsl_counter_clock_enable(struct fsl_pwm_chip *fpc)
-{
- int ret;
-
- /* select counter clock source */
- regmap_update_bits(fpc->regmap, FTM_SC, FTM_SC_CLK_MASK,
- FTM_SC_CLK(fpc->cnt_select));
-
- ret = clk_prepare_enable(fpc->clk[fpc->cnt_select]);
- if (ret)
- return ret;
-
- ret = clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
- if (ret) {
- clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
- return ret;
- }
-
- return 0;
-}
-
-static int fsl_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+static int fsl_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *newstate)
{
struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
- int ret;
-
- mutex_lock(&fpc->lock);
- regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm), 0);
+ struct pwm_state *oldstate = &pwm->state;
+ int ret = 0;
- ret = fsl_counter_clock_enable(fpc);
- mutex_unlock(&fpc->lock);
+ /*
+ * oldstate to newstate : action
+ *
+ * disabled to disabled : ignore
+ * enabled to disabled : disable
+ * enabled to enabled : update settings
+ * disabled to enabled : update settings + enable
+ */
- return ret;
-}
+ mutex_lock(&fpc->lock);
-static void fsl_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
-{
- struct fsl_pwm_chip *fpc = to_fsl_chip(chip);
- u32 val;
+ if (!newstate->enabled) {
+ if (oldstate->enabled) {
+ regmap_update_bits(fpc->regmap, FTM_OUTMASK,
+ BIT(pwm->hwpwm), BIT(pwm->hwpwm));
+ clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
+ clk_disable_unprepare(fpc->clk[fpc->period.clk_select]);
+ }
- mutex_lock(&fpc->lock);
- regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm),
- BIT(pwm->hwpwm));
+ goto end_mutex;
+ }
- clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
- clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
+ ret = fsl_pwm_apply_config(fpc, pwm, newstate);
+ if (ret)
+ goto end_mutex;
+
+ /* check if need to enable */
+ if (!oldstate->enabled) {
+ ret = clk_prepare_enable(fpc->clk[fpc->period.clk_select]);
+ if (ret)
+ goto end_mutex;
+
+ ret = clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
+ if (ret) {
+ clk_disable_unprepare(fpc->clk[fpc->period.clk_select]);
+ goto end_mutex;
+ }
- regmap_read(fpc->regmap, FTM_OUTMASK, &val);
- if ((val & 0xFF) == 0xFF)
- fpc->period_ns = 0;
+ regmap_update_bits(fpc->regmap, FTM_OUTMASK, BIT(pwm->hwpwm),
+ 0);
+ }
+end_mutex:
mutex_unlock(&fpc->lock);
+ return ret;
}
static const struct pwm_ops fsl_pwm_ops = {
.request = fsl_pwm_request,
.free = fsl_pwm_free,
- .config = fsl_pwm_config,
- .set_polarity = fsl_pwm_set_polarity,
- .enable = fsl_pwm_enable,
- .disable = fsl_pwm_disable,
+ .apply = fsl_pwm_apply,
.owner = THIS_MODULE,
};
@@ -357,6 +382,8 @@ static int fsl_pwm_init(struct fsl_pwm_chip *fpc)
static bool fsl_pwm_volatile_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
+ case FTM_FMS:
+ case FTM_MODE:
case FTM_CNT:
return true;
}
@@ -474,7 +501,7 @@ static int fsl_pwm_suspend(struct device *dev)
continue;
clk_disable_unprepare(fpc->clk[FSL_PWM_CLK_CNTEN]);
- clk_disable_unprepare(fpc->clk[fpc->cnt_select]);
+ clk_disable_unprepare(fpc->clk[fpc->period.clk_select]);
}
return 0;
@@ -496,7 +523,7 @@ static int fsl_pwm_resume(struct device *dev)
if (!pwm_is_enabled(pwm))
continue;
- clk_prepare_enable(fpc->clk[fpc->cnt_select]);
+ clk_prepare_enable(fpc->clk[fpc->period.clk_select]);
clk_prepare_enable(fpc->clk[FSL_PWM_CLK_CNTEN]);
}
diff --git a/drivers/pwm/pwm-jz4740.c b/drivers/pwm/pwm-jz4740.c
index 88a51a40e695..f901e8a0d33d 100644
--- a/drivers/pwm/pwm-jz4740.c
+++ b/drivers/pwm/pwm-jz4740.c
@@ -63,7 +63,15 @@ static void jz4740_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
uint32_t ctrl = jz4740_timer_get_ctrl(pwm->hwpwm);
- /* Disable PWM output.
+ /*
+ * Set duty > period. This trick allows the TCU channels in TCU2 mode to
+ * properly return to their init level.
+ */
+ jz4740_timer_set_duty(pwm->hwpwm, 0xffff);
+ jz4740_timer_set_period(pwm->hwpwm, 0x0);
+
+ /*
+ * Disable PWM output.
* In TCU2 mode (channel 1/2 on JZ4750+), this must be done before the
* counter is stopped, while in TCU1 mode the order does not matter.
*/
@@ -74,17 +82,16 @@ static void jz4740_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
jz4740_timer_disable(pwm->hwpwm);
}
-static int jz4740_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
- int duty_ns, int period_ns)
+static int jz4740_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
{
struct jz4740_pwm_chip *jz4740 = to_jz4740(pwm->chip);
unsigned long long tmp;
unsigned long period, duty;
unsigned int prescaler = 0;
uint16_t ctrl;
- bool is_enabled;
- tmp = (unsigned long long)clk_get_rate(jz4740->clk) * period_ns;
+ tmp = (unsigned long long)clk_get_rate(jz4740->clk) * state->period;
do_div(tmp, 1000000000);
period = tmp;
@@ -96,16 +103,14 @@ static int jz4740_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
if (prescaler == 6)
return -EINVAL;
- tmp = (unsigned long long)period * duty_ns;
- do_div(tmp, period_ns);
+ tmp = (unsigned long long)period * state->duty_cycle;
+ do_div(tmp, state->period);
duty = period - tmp;
if (duty >= period)
duty = period - 1;
- is_enabled = jz4740_timer_is_enabled(pwm->hwpwm);
- if (is_enabled)
- jz4740_pwm_disable(chip, pwm);
+ jz4740_pwm_disable(chip, pwm);
jz4740_timer_set_count(pwm->hwpwm, 0);
jz4740_timer_set_duty(pwm->hwpwm, duty);
@@ -116,18 +121,7 @@ static int jz4740_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
- if (is_enabled)
- jz4740_pwm_enable(chip, pwm);
-
- return 0;
-}
-
-static int jz4740_pwm_set_polarity(struct pwm_chip *chip,
- struct pwm_device *pwm, enum pwm_polarity polarity)
-{
- uint32_t ctrl = jz4740_timer_get_ctrl(pwm->pwm);
-
- switch (polarity) {
+ switch (state->polarity) {
case PWM_POLARITY_NORMAL:
ctrl &= ~JZ_TIMER_CTRL_PWM_ACTIVE_LOW;
break;
@@ -137,16 +131,17 @@ static int jz4740_pwm_set_polarity(struct pwm_chip *chip,
}
jz4740_timer_set_ctrl(pwm->hwpwm, ctrl);
+
+ if (state->enabled)
+ jz4740_pwm_enable(chip, pwm);
+
return 0;
}
static const struct pwm_ops jz4740_pwm_ops = {
.request = jz4740_pwm_request,
.free = jz4740_pwm_free,
- .config = jz4740_pwm_config,
- .set_polarity = jz4740_pwm_set_polarity,
- .enable = jz4740_pwm_enable,
- .disable = jz4740_pwm_disable,
+ .apply = jz4740_pwm_apply,
.owner = THIS_MODULE,
};
@@ -184,8 +179,6 @@ static int jz4740_pwm_remove(struct platform_device *pdev)
#ifdef CONFIG_OF
static const struct of_device_id jz4740_pwm_dt_ids[] = {
{ .compatible = "ingenic,jz4740-pwm", },
- { .compatible = "ingenic,jz4770-pwm", },
- { .compatible = "ingenic,jz4780-pwm", },
{},
};
MODULE_DEVICE_TABLE(of, jz4740_pwm_dt_ids);
diff --git a/drivers/pwm/pwm-meson.c b/drivers/pwm/pwm-meson.c
index fb5a369b1a8d..3cbff5cbb789 100644
--- a/drivers/pwm/pwm-meson.c
+++ b/drivers/pwm/pwm-meson.c
@@ -1,65 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
- * This file is provided under a dual BSD/GPLv2 license. When using or
- * redistributing this file, you may do so under either license.
+ * PWM controller driver for Amlogic Meson SoCs.
*
- * GPL LICENSE SUMMARY
+ * This PWM is only a set of Gates, Dividers and Counters:
+ * PWM output is achieved by calculating a clock that permits calculating
+ * two periods (low and high). The counter then has to be set to switch after
+ * N cycles for the first half period.
+ * The hardware has no "polarity" setting. This driver reverses the period
+ * cycles (the low length is inverted with the high length) for
+ * PWM_POLARITY_INVERSED. This means that .get_state cannot read the polarity
+ * from the hardware.
+ * Setting the duty cycle will disable and re-enable the PWM output.
+ * Disabling the PWM stops the output immediately (without waiting for the
+ * current period to complete first).
*
- * Copyright (c) 2016 BayLibre, SAS.
- * Author: Neil Armstrong <narmstrong@baylibre.com>
- * Copyright (C) 2014 Amlogic, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * 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.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
- * The full GNU General Public License is included in this distribution
- * in the file called COPYING.
- *
- * BSD LICENSE
+ * The public S912 (GXM) datasheet contains some documentation for this PWM
+ * controller starting on page 543:
+ * https://dl.khadas.com/Hardware/VIM2/Datasheet/S912_Datasheet_V0.220170314publicversion-Wesion.pdf
+ * An updated version of this IP block is found in S922X (G12B) SoCs. The
+ * datasheet contains the description for this IP block revision starting at
+ * page 1084:
+ * https://dn.odroid.com/S922X/ODROID-N2/Datasheet/S922X_Public_Datasheet_V0.2.pdf
*
* Copyright (c) 2016 BayLibre, SAS.
* Author: Neil Armstrong <narmstrong@baylibre.com>
* Copyright (C) 2014 Amlogic, Inc.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * * Neither the name of Intel Corporation nor the names of its
- * contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
+#include <linux/bitfield.h>
+#include <linux/bits.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
+#include <linux/math64.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
@@ -70,7 +45,8 @@
#define REG_PWM_A 0x0
#define REG_PWM_B 0x4
-#define PWM_HIGH_SHIFT 16
+#define PWM_LOW_MASK GENMASK(15, 0)
+#define PWM_HIGH_MASK GENMASK(31, 16)
#define REG_MISC_AB 0x8
#define MISC_B_CLK_EN BIT(23)
@@ -80,13 +56,33 @@
#define MISC_A_CLK_DIV_SHIFT 8
#define MISC_B_CLK_SEL_SHIFT 6
#define MISC_A_CLK_SEL_SHIFT 4
-#define MISC_CLK_SEL_WIDTH 2
+#define MISC_CLK_SEL_MASK 0x3
#define MISC_B_EN BIT(1)
#define MISC_A_EN BIT(0)
-static const unsigned int mux_reg_shifts[] = {
- MISC_A_CLK_SEL_SHIFT,
- MISC_B_CLK_SEL_SHIFT
+#define MESON_NUM_PWMS 2
+
+static struct meson_pwm_channel_data {
+ u8 reg_offset;
+ u8 clk_sel_shift;
+ u8 clk_div_shift;
+ u32 clk_en_mask;
+ u32 pwm_en_mask;
+} meson_pwm_per_channel_data[MESON_NUM_PWMS] = {
+ {
+ .reg_offset = REG_PWM_A,
+ .clk_sel_shift = MISC_A_CLK_SEL_SHIFT,
+ .clk_div_shift = MISC_A_CLK_DIV_SHIFT,
+ .clk_en_mask = MISC_A_CLK_EN,
+ .pwm_en_mask = MISC_A_EN,
+ },
+ {
+ .reg_offset = REG_PWM_B,
+ .clk_sel_shift = MISC_B_CLK_SEL_SHIFT,
+ .clk_div_shift = MISC_B_CLK_DIV_SHIFT,
+ .clk_en_mask = MISC_B_CLK_EN,
+ .pwm_en_mask = MISC_B_EN,
+ }
};
struct meson_pwm_channel {
@@ -94,8 +90,6 @@ struct meson_pwm_channel {
unsigned int lo;
u8 pre_div;
- struct pwm_state state;
-
struct clk *clk_parent;
struct clk_mux mux;
struct clk *clk;
@@ -109,8 +103,8 @@ struct meson_pwm_data {
struct meson_pwm {
struct pwm_chip chip;
const struct meson_pwm_data *data;
+ struct meson_pwm_channel channels[MESON_NUM_PWMS];
void __iomem *base;
- u8 inverter_mask;
/*
* Protects register (write) access to the REG_MISC_AB register
* that is shared between the two PWMs.
@@ -125,12 +119,16 @@ static inline struct meson_pwm *to_meson_pwm(struct pwm_chip *chip)
static int meson_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
{
- struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
+ struct meson_pwm *meson = to_meson_pwm(chip);
+ struct meson_pwm_channel *channel;
struct device *dev = chip->dev;
int err;
- if (!channel)
- return -ENODEV;
+ channel = pwm_get_chip_data(pwm);
+ if (channel)
+ return 0;
+
+ channel = &meson->channels[pwm->hwpwm];
if (channel->clk_parent) {
err = clk_set_parent(channel->clk, channel->clk_parent);
@@ -149,9 +147,7 @@ static int meson_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
return err;
}
- chip->ops->get_state(chip, pwm, &channel->state);
-
- return 0;
+ return pwm_set_chip_data(pwm, channel);
}
static void meson_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
@@ -162,20 +158,18 @@ static void meson_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm)
clk_disable_unprepare(channel->clk);
}
-static int meson_pwm_calc(struct meson_pwm *meson,
- struct meson_pwm_channel *channel, unsigned int id,
- unsigned int duty, unsigned int period)
+static int meson_pwm_calc(struct meson_pwm *meson, struct pwm_device *pwm,
+ struct pwm_state *state)
{
- unsigned int pre_div, cnt, duty_cnt;
+ struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
+ unsigned int duty, period, pre_div, cnt, duty_cnt;
unsigned long fin_freq = -1;
- u64 fin_ps;
- if (~(meson->inverter_mask >> id) & 0x1)
- duty = period - duty;
+ duty = state->duty_cycle;
+ period = state->period;
- if (period == channel->state.period &&
- duty == channel->state.duty_cycle)
- return 0;
+ if (state->polarity == PWM_POLARITY_INVERSED)
+ duty = period - duty;
fin_freq = clk_get_rate(channel->clk);
if (fin_freq == 0) {
@@ -184,24 +178,19 @@ static int meson_pwm_calc(struct meson_pwm *meson,
}
dev_dbg(meson->chip.dev, "fin_freq: %lu Hz\n", fin_freq);
- fin_ps = (u64)NSEC_PER_SEC * 1000;
- do_div(fin_ps, fin_freq);
-
- /* Calc pre_div with the period */
- for (pre_div = 0; pre_div <= MISC_CLK_DIV_MASK; pre_div++) {
- cnt = DIV_ROUND_CLOSEST_ULL((u64)period * 1000,
- fin_ps * (pre_div + 1));
- dev_dbg(meson->chip.dev, "fin_ps=%llu pre_div=%u cnt=%u\n",
- fin_ps, pre_div, cnt);
- if (cnt <= 0xffff)
- break;
- }
+ pre_div = div64_u64(fin_freq * (u64)period, NSEC_PER_SEC * 0xffffLL);
if (pre_div > MISC_CLK_DIV_MASK) {
dev_err(meson->chip.dev, "unable to get period pre_div\n");
return -EINVAL;
}
+ cnt = div64_u64(fin_freq * (u64)period, NSEC_PER_SEC * (pre_div + 1));
+ if (cnt > 0xffff) {
+ dev_err(meson->chip.dev, "unable to get period cnt\n");
+ return -EINVAL;
+ }
+
dev_dbg(meson->chip.dev, "period=%u pre_div=%u cnt=%u\n", period,
pre_div, cnt);
@@ -215,8 +204,8 @@ static int meson_pwm_calc(struct meson_pwm *meson,
channel->lo = cnt;
} else {
/* Then check is we can have the duty with the same pre_div */
- duty_cnt = DIV_ROUND_CLOSEST_ULL((u64)duty * 1000,
- fin_ps * (pre_div + 1));
+ duty_cnt = div64_u64(fin_freq * (u64)duty,
+ NSEC_PER_SEC * (pre_div + 1));
if (duty_cnt > 0xffff) {
dev_err(meson->chip.dev, "unable to get duty cycle\n");
return -EINVAL;
@@ -233,73 +222,43 @@ static int meson_pwm_calc(struct meson_pwm *meson,
return 0;
}
-static void meson_pwm_enable(struct meson_pwm *meson,
- struct meson_pwm_channel *channel,
- unsigned int id)
+static void meson_pwm_enable(struct meson_pwm *meson, struct pwm_device *pwm)
{
- u32 value, clk_shift, clk_enable, enable;
- unsigned int offset;
+ struct meson_pwm_channel *channel = pwm_get_chip_data(pwm);
+ struct meson_pwm_channel_data *channel_data;
unsigned long flags;
+ u32 value;
- switch (id) {
- case 0:
- clk_shift = MISC_A_CLK_DIV_SHIFT;
- clk_enable = MISC_A_CLK_EN;
- enable = MISC_A_EN;
- offset = REG_PWM_A;
- break;
-
- case 1:
- clk_shift = MISC_B_CLK_DIV_SHIFT;
- clk_enable = MISC_B_CLK_EN;
- enable = MISC_B_EN;
- offset = REG_PWM_B;
- break;
-
- default:
- return;
- }
+ channel_data = &meson_pwm_per_channel_data[pwm->hwpwm];
spin_lock_irqsave(&meson->lock, flags);
value = readl(meson->base + REG_MISC_AB);
- value &= ~(MISC_CLK_DIV_MASK << clk_shift);
- value |= channel->pre_div << clk_shift;
- value |= clk_enable;
+ value &= ~(MISC_CLK_DIV_MASK << channel_data->clk_div_shift);
+ value |= channel->pre_div << channel_data->clk_div_shift;
+ value |= channel_data->clk_en_mask;
writel(value, meson->base + REG_MISC_AB);
- value = (channel->hi << PWM_HIGH_SHIFT) | channel->lo;
- writel(value, meson->base + offset);
+ value = FIELD_PREP(PWM_HIGH_MASK, channel->hi) |
+ FIELD_PREP(PWM_LOW_MASK, channel->lo);
+ writel(value, meson->base + channel_data->reg_offset);
value = readl(meson->base + REG_MISC_AB);
- value |= enable;
+ value |= channel_data->pwm_en_mask;
writel(value, meson->base + REG_MISC_AB);
spin_unlock_irqrestore(&meson->lock, flags);
}
-static void meson_pwm_disable(struct meson_pwm *meson, unsigned int id)
+static void meson_pwm_disable(struct meson_pwm *meson, struct pwm_device *pwm)
{
- u32 value, enable;
unsigned long flags;
-
- switch (id) {
- case 0:
- enable = MISC_A_EN;
- break;
-
- case 1:
- enable = MISC_B_EN;
- break;
-
- default:
- return;
- }
+ u32 value;
spin_lock_irqsave(&meson->lock, flags);
value = readl(meson->base + REG_MISC_AB);
- value &= ~enable;
+ value &= ~meson_pwm_per_channel_data[pwm->hwpwm].pwm_en_mask;
writel(value, meson->base + REG_MISC_AB);
spin_unlock_irqrestore(&meson->lock, flags);
@@ -316,64 +275,97 @@ static int meson_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
if (!state->enabled) {
- meson_pwm_disable(meson, pwm->hwpwm);
- channel->state.enabled = false;
-
- return 0;
- }
-
- if (state->period != channel->state.period ||
- state->duty_cycle != channel->state.duty_cycle ||
- state->polarity != channel->state.polarity) {
- if (state->polarity != channel->state.polarity) {
- if (state->polarity == PWM_POLARITY_NORMAL)
- meson->inverter_mask |= BIT(pwm->hwpwm);
- else
- meson->inverter_mask &= ~BIT(pwm->hwpwm);
+ if (state->polarity == PWM_POLARITY_INVERSED) {
+ /*
+ * This IP block revision doesn't have an "always high"
+ * setting which we can use for "inverted disabled".
+ * Instead we achieve this using the same settings
+ * that we use a pre_div of 0 (to get the shortest
+ * possible duration for one "count") and
+ * "period == duty_cycle". This results in a signal
+ * which is LOW for one "count", while being HIGH for
+ * the rest of the (so the signal is HIGH for slightly
+ * less than 100% of the period, but this is the best
+ * we can achieve).
+ */
+ channel->pre_div = 0;
+ channel->hi = ~0;
+ channel->lo = 0;
+
+ meson_pwm_enable(meson, pwm);
+ } else {
+ meson_pwm_disable(meson, pwm);
}
-
- err = meson_pwm_calc(meson, channel, pwm->hwpwm,
- state->duty_cycle, state->period);
+ } else {
+ err = meson_pwm_calc(meson, pwm, state);
if (err < 0)
return err;
- channel->state.polarity = state->polarity;
- channel->state.period = state->period;
- channel->state.duty_cycle = state->duty_cycle;
- }
-
- if (state->enabled && !channel->state.enabled) {
- meson_pwm_enable(meson, channel, pwm->hwpwm);
- channel->state.enabled = true;
+ meson_pwm_enable(meson, pwm);
}
return 0;
}
+static unsigned int meson_pwm_cnt_to_ns(struct pwm_chip *chip,
+ struct pwm_device *pwm, u32 cnt)
+{
+ struct meson_pwm *meson = to_meson_pwm(chip);
+ struct meson_pwm_channel *channel;
+ unsigned long fin_freq;
+ u32 fin_ns;
+
+ /* to_meson_pwm() can only be used after .get_state() is called */
+ channel = &meson->channels[pwm->hwpwm];
+
+ fin_freq = clk_get_rate(channel->clk);
+ if (fin_freq == 0)
+ return 0;
+
+ fin_ns = div_u64(NSEC_PER_SEC, fin_freq);
+
+ return cnt * fin_ns * (channel->pre_div + 1);
+}
+
static void meson_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
struct pwm_state *state)
{
struct meson_pwm *meson = to_meson_pwm(chip);
- u32 value, mask;
+ struct meson_pwm_channel_data *channel_data;
+ struct meson_pwm_channel *channel;
+ u32 value, tmp;
if (!state)
return;
- switch (pwm->hwpwm) {
- case 0:
- mask = MISC_A_EN;
- break;
+ channel = &meson->channels[pwm->hwpwm];
+ channel_data = &meson_pwm_per_channel_data[pwm->hwpwm];
- case 1:
- mask = MISC_B_EN;
- break;
+ value = readl(meson->base + REG_MISC_AB);
- default:
- return;
- }
+ tmp = channel_data->pwm_en_mask | channel_data->clk_en_mask;
+ state->enabled = (value & tmp) == tmp;
- value = readl(meson->base + REG_MISC_AB);
- state->enabled = (value & mask) != 0;
+ tmp = value >> channel_data->clk_div_shift;
+ channel->pre_div = FIELD_GET(MISC_CLK_DIV_MASK, tmp);
+
+ value = readl(meson->base + channel_data->reg_offset);
+
+ channel->lo = FIELD_GET(PWM_LOW_MASK, value);
+ channel->hi = FIELD_GET(PWM_HIGH_MASK, value);
+
+ if (channel->lo == 0) {
+ state->period = meson_pwm_cnt_to_ns(chip, pwm, channel->hi);
+ state->duty_cycle = state->period;
+ } else if (channel->lo >= channel->hi) {
+ state->period = meson_pwm_cnt_to_ns(chip, pwm,
+ channel->lo + channel->hi);
+ state->duty_cycle = meson_pwm_cnt_to_ns(chip, pwm,
+ channel->hi);
+ } else {
+ state->period = 0;
+ state->duty_cycle = 0;
+ }
}
static const struct pwm_ops meson_pwm_ops = {
@@ -433,8 +425,17 @@ static const struct meson_pwm_data pwm_axg_ao_data = {
.num_parents = ARRAY_SIZE(pwm_axg_ao_parent_names),
};
+static const char * const pwm_g12a_ao_ab_parent_names[] = {
+ "xtal", "aoclk81", "fclk_div4", "fclk_div5"
+};
+
+static const struct meson_pwm_data pwm_g12a_ao_ab_data = {
+ .parent_names = pwm_g12a_ao_ab_parent_names,
+ .num_parents = ARRAY_SIZE(pwm_g12a_ao_ab_parent_names),
+};
+
static const char * const pwm_g12a_ao_cd_parent_names[] = {
- "aoclk81", "xtal",
+ "xtal", "aoclk81",
};
static const struct meson_pwm_data pwm_g12a_ao_cd_data = {
@@ -478,7 +479,7 @@ static const struct of_device_id meson_pwm_matches[] = {
},
{
.compatible = "amlogic,meson-g12a-ao-pwm-ab",
- .data = &pwm_axg_ao_data
+ .data = &pwm_g12a_ao_ab_data
},
{
.compatible = "amlogic,meson-g12a-ao-pwm-cd",
@@ -488,8 +489,7 @@ static const struct of_device_id meson_pwm_matches[] = {
};
MODULE_DEVICE_TABLE(of, meson_pwm_matches);
-static int meson_pwm_init_channels(struct meson_pwm *meson,
- struct meson_pwm_channel *channels)
+static int meson_pwm_init_channels(struct meson_pwm *meson)
{
struct device *dev = meson->chip.dev;
struct clk_init_data init;
@@ -498,7 +498,7 @@ static int meson_pwm_init_channels(struct meson_pwm *meson,
int err;
for (i = 0; i < meson->chip.npwm; i++) {
- struct meson_pwm_channel *channel = &channels[i];
+ struct meson_pwm_channel *channel = &meson->channels[i];
snprintf(name, sizeof(name), "%s#mux%u", dev_name(dev), i);
@@ -509,8 +509,9 @@ static int meson_pwm_init_channels(struct meson_pwm *meson,
init.num_parents = meson->data->num_parents;
channel->mux.reg = meson->base + REG_MISC_AB;
- channel->mux.shift = mux_reg_shifts[i];
- channel->mux.mask = BIT(MISC_CLK_SEL_WIDTH) - 1;
+ channel->mux.shift =
+ meson_pwm_per_channel_data[i].clk_sel_shift;
+ channel->mux.mask = MISC_CLK_SEL_MASK;
channel->mux.flags = 0;
channel->mux.lock = &meson->lock;
channel->mux.table = NULL;
@@ -525,31 +526,16 @@ static int meson_pwm_init_channels(struct meson_pwm *meson,
snprintf(name, sizeof(name), "clkin%u", i);
- channel->clk_parent = devm_clk_get(dev, name);
- if (IS_ERR(channel->clk_parent)) {
- err = PTR_ERR(channel->clk_parent);
- if (err == -EPROBE_DEFER)
- return err;
-
- channel->clk_parent = NULL;
- }
+ channel->clk_parent = devm_clk_get_optional(dev, name);
+ if (IS_ERR(channel->clk_parent))
+ return PTR_ERR(channel->clk_parent);
}
return 0;
}
-static void meson_pwm_add_channels(struct meson_pwm *meson,
- struct meson_pwm_channel *channels)
-{
- unsigned int i;
-
- for (i = 0; i < meson->chip.npwm; i++)
- pwm_set_chip_data(&meson->chip.pwms[i], &channels[i]);
-}
-
static int meson_pwm_probe(struct platform_device *pdev)
{
- struct meson_pwm_channel *channels;
struct meson_pwm *meson;
struct resource *regs;
int err;
@@ -567,19 +553,13 @@ static int meson_pwm_probe(struct platform_device *pdev)
meson->chip.dev = &pdev->dev;
meson->chip.ops = &meson_pwm_ops;
meson->chip.base = -1;
- meson->chip.npwm = 2;
+ meson->chip.npwm = MESON_NUM_PWMS;
meson->chip.of_xlate = of_pwm_xlate_with_flags;
meson->chip.of_pwm_n_cells = 3;
meson->data = of_device_get_match_data(&pdev->dev);
- meson->inverter_mask = BIT(meson->chip.npwm) - 1;
- channels = devm_kcalloc(&pdev->dev, meson->chip.npwm,
- sizeof(*channels), GFP_KERNEL);
- if (!channels)
- return -ENOMEM;
-
- err = meson_pwm_init_channels(meson, channels);
+ err = meson_pwm_init_channels(meson);
if (err < 0)
return err;
@@ -589,8 +569,6 @@ static int meson_pwm_probe(struct platform_device *pdev)
return err;
}
- meson_pwm_add_channels(meson, channels);
-
platform_set_drvdata(pdev, meson);
return 0;
diff --git a/drivers/pwm/pwm-rcar.c b/drivers/pwm/pwm-rcar.c
index cfe7dd1b448e..5b2b8ecc354c 100644
--- a/drivers/pwm/pwm-rcar.c
+++ b/drivers/pwm/pwm-rcar.c
@@ -254,50 +254,11 @@ static const struct of_device_id rcar_pwm_of_table[] = {
};
MODULE_DEVICE_TABLE(of, rcar_pwm_of_table);
-#ifdef CONFIG_PM_SLEEP
-static struct pwm_device *rcar_pwm_dev_to_pwm_dev(struct device *dev)
-{
- struct rcar_pwm_chip *rcar_pwm = dev_get_drvdata(dev);
- struct pwm_chip *chip = &rcar_pwm->chip;
-
- return &chip->pwms[0];
-}
-
-static int rcar_pwm_suspend(struct device *dev)
-{
- struct pwm_device *pwm = rcar_pwm_dev_to_pwm_dev(dev);
-
- if (!test_bit(PWMF_REQUESTED, &pwm->flags))
- return 0;
-
- pm_runtime_put(dev);
-
- return 0;
-}
-
-static int rcar_pwm_resume(struct device *dev)
-{
- struct pwm_device *pwm = rcar_pwm_dev_to_pwm_dev(dev);
- struct pwm_state state;
-
- if (!test_bit(PWMF_REQUESTED, &pwm->flags))
- return 0;
-
- pm_runtime_get_sync(dev);
-
- pwm_get_state(pwm, &state);
-
- return rcar_pwm_apply(pwm->chip, pwm, &state);
-}
-#endif /* CONFIG_PM_SLEEP */
-static SIMPLE_DEV_PM_OPS(rcar_pwm_pm_ops, rcar_pwm_suspend, rcar_pwm_resume);
-
static struct platform_driver rcar_pwm_driver = {
.probe = rcar_pwm_probe,
.remove = rcar_pwm_remove,
.driver = {
.name = "pwm-rcar",
- .pm = &rcar_pwm_pm_ops,
.of_match_table = of_match_ptr(rcar_pwm_of_table),
}
};
diff --git a/drivers/pwm/pwm-sifive.c b/drivers/pwm/pwm-sifive.c
new file mode 100644
index 000000000000..a7c107f19e66
--- /dev/null
+++ b/drivers/pwm/pwm-sifive.c
@@ -0,0 +1,339 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017-2018 SiFive
+ * For SiFive's PWM IP block documentation please refer Chapter 14 of
+ * Reference Manual : https://static.dev.sifive.com/FU540-C000-v1.0.pdf
+ *
+ * Limitations:
+ * - When changing both duty cycle and period, we cannot prevent in
+ * software that the output might produce a period with mixed
+ * settings (new period length and old duty cycle).
+ * - The hardware cannot generate a 100% duty cycle.
+ * - The hardware generates only inverted output.
+ */
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+#include <linux/slab.h>
+#include <linux/bitfield.h>
+
+/* Register offsets */
+#define PWM_SIFIVE_PWMCFG 0x0
+#define PWM_SIFIVE_PWMCOUNT 0x8
+#define PWM_SIFIVE_PWMS 0x10
+#define PWM_SIFIVE_PWMCMP0 0x20
+
+/* PWMCFG fields */
+#define PWM_SIFIVE_PWMCFG_SCALE GENMASK(3, 0)
+#define PWM_SIFIVE_PWMCFG_STICKY BIT(8)
+#define PWM_SIFIVE_PWMCFG_ZERO_CMP BIT(9)
+#define PWM_SIFIVE_PWMCFG_DEGLITCH BIT(10)
+#define PWM_SIFIVE_PWMCFG_EN_ALWAYS BIT(12)
+#define PWM_SIFIVE_PWMCFG_EN_ONCE BIT(13)
+#define PWM_SIFIVE_PWMCFG_CENTER BIT(16)
+#define PWM_SIFIVE_PWMCFG_GANG BIT(24)
+#define PWM_SIFIVE_PWMCFG_IP BIT(28)
+
+/* PWM_SIFIVE_SIZE_PWMCMP is used to calculate offset for pwmcmpX registers */
+#define PWM_SIFIVE_SIZE_PWMCMP 4
+#define PWM_SIFIVE_CMPWIDTH 16
+#define PWM_SIFIVE_DEFAULT_PERIOD 10000000
+
+struct pwm_sifive_ddata {
+ struct pwm_chip chip;
+ struct mutex lock; /* lock to protect user_count */
+ struct notifier_block notifier;
+ struct clk *clk;
+ void __iomem *regs;
+ unsigned int real_period;
+ unsigned int approx_period;
+ int user_count;
+};
+
+static inline
+struct pwm_sifive_ddata *pwm_sifive_chip_to_ddata(struct pwm_chip *c)
+{
+ return container_of(c, struct pwm_sifive_ddata, chip);
+}
+
+static int pwm_sifive_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip);
+
+ mutex_lock(&ddata->lock);
+ ddata->user_count++;
+ mutex_unlock(&ddata->lock);
+
+ return 0;
+}
+
+static void pwm_sifive_free(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip);
+
+ mutex_lock(&ddata->lock);
+ ddata->user_count--;
+ mutex_unlock(&ddata->lock);
+}
+
+static void pwm_sifive_update_clock(struct pwm_sifive_ddata *ddata,
+ unsigned long rate)
+{
+ unsigned long long num;
+ unsigned long scale_pow;
+ int scale;
+ u32 val;
+ /*
+ * The PWM unit is used with pwmzerocmp=0, so the only way to modify the
+ * period length is using pwmscale which provides the number of bits the
+ * counter is shifted before being feed to the comparators. A period
+ * lasts (1 << (PWM_SIFIVE_CMPWIDTH + pwmscale)) clock ticks.
+ * (1 << (PWM_SIFIVE_CMPWIDTH + scale)) * 10^9/rate = period
+ */
+ scale_pow = div64_ul(ddata->approx_period * (u64)rate, NSEC_PER_SEC);
+ scale = clamp(ilog2(scale_pow) - PWM_SIFIVE_CMPWIDTH, 0, 0xf);
+
+ val = PWM_SIFIVE_PWMCFG_EN_ALWAYS |
+ FIELD_PREP(PWM_SIFIVE_PWMCFG_SCALE, scale);
+ writel(val, ddata->regs + PWM_SIFIVE_PWMCFG);
+
+ /* As scale <= 15 the shift operation cannot overflow. */
+ num = (unsigned long long)NSEC_PER_SEC << (PWM_SIFIVE_CMPWIDTH + scale);
+ ddata->real_period = div64_ul(num, rate);
+ dev_dbg(ddata->chip.dev,
+ "New real_period = %u ns\n", ddata->real_period);
+}
+
+static void pwm_sifive_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip);
+ u32 duty, val;
+
+ duty = readl(ddata->regs + PWM_SIFIVE_PWMCMP0 +
+ pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP);
+
+ state->enabled = duty > 0;
+
+ val = readl(ddata->regs + PWM_SIFIVE_PWMCFG);
+ if (!(val & PWM_SIFIVE_PWMCFG_EN_ALWAYS))
+ state->enabled = false;
+
+ state->period = ddata->real_period;
+ state->duty_cycle =
+ (u64)duty * ddata->real_period >> PWM_SIFIVE_CMPWIDTH;
+ state->polarity = PWM_POLARITY_INVERSED;
+}
+
+static int pwm_sifive_enable(struct pwm_chip *chip, bool enable)
+{
+ struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip);
+ int ret;
+
+ if (enable) {
+ ret = clk_enable(ddata->clk);
+ if (ret) {
+ dev_err(ddata->chip.dev, "Enable clk failed\n");
+ return ret;
+ }
+ }
+
+ if (!enable)
+ clk_disable(ddata->clk);
+
+ return 0;
+}
+
+static int pwm_sifive_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct pwm_sifive_ddata *ddata = pwm_sifive_chip_to_ddata(chip);
+ struct pwm_state cur_state;
+ unsigned int duty_cycle;
+ unsigned long long num;
+ bool enabled;
+ int ret = 0;
+ u32 frac;
+
+ if (state->polarity != PWM_POLARITY_INVERSED)
+ return -EINVAL;
+
+ ret = clk_enable(ddata->clk);
+ if (ret) {
+ dev_err(ddata->chip.dev, "Enable clk failed\n");
+ return ret;
+ }
+
+ mutex_lock(&ddata->lock);
+ cur_state = pwm->state;
+ enabled = cur_state.enabled;
+
+ duty_cycle = state->duty_cycle;
+ if (!state->enabled)
+ duty_cycle = 0;
+
+ /*
+ * The problem of output producing mixed setting as mentioned at top,
+ * occurs here. To minimize the window for this problem, we are
+ * calculating the register values first and then writing them
+ * consecutively
+ */
+ num = (u64)duty_cycle * (1U << PWM_SIFIVE_CMPWIDTH);
+ frac = DIV_ROUND_CLOSEST_ULL(num, state->period);
+ /* The hardware cannot generate a 100% duty cycle */
+ frac = min(frac, (1U << PWM_SIFIVE_CMPWIDTH) - 1);
+
+ if (state->period != ddata->approx_period) {
+ if (ddata->user_count != 1) {
+ ret = -EBUSY;
+ goto exit;
+ }
+ ddata->approx_period = state->period;
+ pwm_sifive_update_clock(ddata, clk_get_rate(ddata->clk));
+ }
+
+ writel(frac, ddata->regs + PWM_SIFIVE_PWMCMP0 +
+ pwm->hwpwm * PWM_SIFIVE_SIZE_PWMCMP);
+
+ if (state->enabled != enabled)
+ pwm_sifive_enable(chip, state->enabled);
+
+exit:
+ clk_disable(ddata->clk);
+ mutex_unlock(&ddata->lock);
+ return ret;
+}
+
+static const struct pwm_ops pwm_sifive_ops = {
+ .request = pwm_sifive_request,
+ .free = pwm_sifive_free,
+ .get_state = pwm_sifive_get_state,
+ .apply = pwm_sifive_apply,
+ .owner = THIS_MODULE,
+};
+
+static int pwm_sifive_clock_notifier(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct clk_notifier_data *ndata = data;
+ struct pwm_sifive_ddata *ddata =
+ container_of(nb, struct pwm_sifive_ddata, notifier);
+
+ if (event == POST_RATE_CHANGE)
+ pwm_sifive_update_clock(ddata, ndata->new_rate);
+
+ return NOTIFY_OK;
+}
+
+static int pwm_sifive_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct pwm_sifive_ddata *ddata;
+ struct pwm_chip *chip;
+ struct resource *res;
+ int ret;
+
+ ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
+ if (!ddata)
+ return -ENOMEM;
+
+ mutex_init(&ddata->lock);
+ chip = &ddata->chip;
+ chip->dev = dev;
+ chip->ops = &pwm_sifive_ops;
+ chip->of_xlate = of_pwm_xlate_with_flags;
+ chip->of_pwm_n_cells = 3;
+ chip->base = -1;
+ chip->npwm = 4;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ddata->regs = devm_ioremap_resource(dev, res);
+ if (IS_ERR(ddata->regs)) {
+ dev_err(dev, "Unable to map IO resources\n");
+ return PTR_ERR(ddata->regs);
+ }
+
+ ddata->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(ddata->clk)) {
+ if (PTR_ERR(ddata->clk) != -EPROBE_DEFER)
+ dev_err(dev, "Unable to find controller clock\n");
+ return PTR_ERR(ddata->clk);
+ }
+
+ ret = clk_prepare_enable(ddata->clk);
+ if (ret) {
+ dev_err(dev, "failed to enable clock for pwm: %d\n", ret);
+ return ret;
+ }
+
+ /* Watch for changes to underlying clock frequency */
+ ddata->notifier.notifier_call = pwm_sifive_clock_notifier;
+ ret = clk_notifier_register(ddata->clk, &ddata->notifier);
+ if (ret) {
+ dev_err(dev, "failed to register clock notifier: %d\n", ret);
+ goto disable_clk;
+ }
+
+ ret = pwmchip_add(chip);
+ if (ret < 0) {
+ dev_err(dev, "cannot register PWM: %d\n", ret);
+ goto unregister_clk;
+ }
+
+ platform_set_drvdata(pdev, ddata);
+ dev_dbg(dev, "SiFive PWM chip registered %d PWMs\n", chip->npwm);
+
+ return 0;
+
+unregister_clk:
+ clk_notifier_unregister(ddata->clk, &ddata->notifier);
+disable_clk:
+ clk_disable_unprepare(ddata->clk);
+
+ return ret;
+}
+
+static int pwm_sifive_remove(struct platform_device *dev)
+{
+ struct pwm_sifive_ddata *ddata = platform_get_drvdata(dev);
+ bool is_enabled = false;
+ struct pwm_device *pwm;
+ int ret, ch;
+
+ for (ch = 0; ch < ddata->chip.npwm; ch++) {
+ pwm = &ddata->chip.pwms[ch];
+ if (pwm->state.enabled) {
+ is_enabled = true;
+ break;
+ }
+ }
+ if (is_enabled)
+ clk_disable(ddata->clk);
+
+ clk_disable_unprepare(ddata->clk);
+ ret = pwmchip_remove(&ddata->chip);
+ clk_notifier_unregister(ddata->clk, &ddata->notifier);
+
+ return ret;
+}
+
+static const struct of_device_id pwm_sifive_of_match[] = {
+ { .compatible = "sifive,pwm0" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, pwm_sifive_of_match);
+
+static struct platform_driver pwm_sifive_driver = {
+ .probe = pwm_sifive_probe,
+ .remove = pwm_sifive_remove,
+ .driver = {
+ .name = "pwm-sifive",
+ .of_match_table = pwm_sifive_of_match,
+ },
+};
+module_platform_driver(pwm_sifive_driver);
+
+MODULE_DESCRIPTION("SiFive PWM driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/pwm/pwm-stm32-lp.c b/drivers/pwm/pwm-stm32-lp.c
index 0059b24cfdc3..2211a642066d 100644
--- a/drivers/pwm/pwm-stm32-lp.c
+++ b/drivers/pwm/pwm-stm32-lp.c
@@ -13,6 +13,7 @@
#include <linux/mfd/stm32-lptimer.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pwm.h>
@@ -223,6 +224,29 @@ static int stm32_pwm_lp_remove(struct platform_device *pdev)
return pwmchip_remove(&priv->chip);
}
+static int __maybe_unused stm32_pwm_lp_suspend(struct device *dev)
+{
+ struct stm32_pwm_lp *priv = dev_get_drvdata(dev);
+ struct pwm_state state;
+
+ pwm_get_state(&priv->chip.pwms[0], &state);
+ if (state.enabled) {
+ dev_err(dev, "The consumer didn't stop us (%s)\n",
+ priv->chip.pwms[0].label);
+ return -EBUSY;
+ }
+
+ return pinctrl_pm_select_sleep_state(dev);
+}
+
+static int __maybe_unused stm32_pwm_lp_resume(struct device *dev)
+{
+ return pinctrl_pm_select_default_state(dev);
+}
+
+static SIMPLE_DEV_PM_OPS(stm32_pwm_lp_pm_ops, stm32_pwm_lp_suspend,
+ stm32_pwm_lp_resume);
+
static const struct of_device_id stm32_pwm_lp_of_match[] = {
{ .compatible = "st,stm32-pwm-lp", },
{},
@@ -235,6 +259,7 @@ static struct platform_driver stm32_pwm_lp_driver = {
.driver = {
.name = "stm32-pwm-lp",
.of_match_table = of_match_ptr(stm32_pwm_lp_of_match),
+ .pm = &stm32_pwm_lp_pm_ops,
},
};
module_platform_driver(stm32_pwm_lp_driver);
diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c
index 4f842550fbd1..740e2dec8313 100644
--- a/drivers/pwm/pwm-stm32.c
+++ b/drivers/pwm/pwm-stm32.c
@@ -608,6 +608,8 @@ static int stm32_pwm_probe(struct platform_device *pdev)
priv->regmap = ddata->regmap;
priv->clk = ddata->clk;
priv->max_arr = ddata->max_arr;
+ priv->chip.of_xlate = of_pwm_xlate_with_flags;
+ priv->chip.of_pwm_n_cells = 3;
if (!priv->regmap || !priv->clk)
return -EINVAL;
diff --git a/drivers/pwm/sysfs.c b/drivers/pwm/sysfs.c
index bf6823fe0812..2389b8669846 100644
--- a/drivers/pwm/sysfs.c
+++ b/drivers/pwm/sysfs.c
@@ -18,6 +18,7 @@ struct pwm_export {
struct device child;
struct pwm_device *pwm;
struct mutex lock;
+ struct pwm_state suspend;
};
static struct pwm_export *child_to_pwm_export(struct device *child)
@@ -372,10 +373,111 @@ static struct attribute *pwm_chip_attrs[] = {
};
ATTRIBUTE_GROUPS(pwm_chip);
+/* takes export->lock on success */
+static struct pwm_export *pwm_class_get_state(struct device *parent,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct device *child;
+ struct pwm_export *export;
+
+ if (!test_bit(PWMF_EXPORTED, &pwm->flags))
+ return NULL;
+
+ child = device_find_child(parent, pwm, pwm_unexport_match);
+ if (!child)
+ return NULL;
+
+ export = child_to_pwm_export(child);
+ put_device(child); /* for device_find_child() */
+
+ mutex_lock(&export->lock);
+ pwm_get_state(pwm, state);
+
+ return export;
+}
+
+static int pwm_class_apply_state(struct pwm_export *export,
+ struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ int ret = pwm_apply_state(pwm, state);
+
+ /* release lock taken in pwm_class_get_state */
+ mutex_unlock(&export->lock);
+
+ return ret;
+}
+
+static int pwm_class_resume_npwm(struct device *parent, unsigned int npwm)
+{
+ struct pwm_chip *chip = dev_get_drvdata(parent);
+ unsigned int i;
+ int ret = 0;
+
+ for (i = 0; i < npwm; i++) {
+ struct pwm_device *pwm = &chip->pwms[i];
+ struct pwm_state state;
+ struct pwm_export *export;
+
+ export = pwm_class_get_state(parent, pwm, &state);
+ if (!export)
+ continue;
+
+ state.enabled = export->suspend.enabled;
+ ret = pwm_class_apply_state(export, pwm, &state);
+ if (ret < 0)
+ break;
+ }
+
+ return ret;
+}
+
+static int __maybe_unused pwm_class_suspend(struct device *parent)
+{
+ struct pwm_chip *chip = dev_get_drvdata(parent);
+ unsigned int i;
+ int ret = 0;
+
+ for (i = 0; i < chip->npwm; i++) {
+ struct pwm_device *pwm = &chip->pwms[i];
+ struct pwm_state state;
+ struct pwm_export *export;
+
+ export = pwm_class_get_state(parent, pwm, &state);
+ if (!export)
+ continue;
+
+ export->suspend = state;
+ state.enabled = false;
+ ret = pwm_class_apply_state(export, pwm, &state);
+ if (ret < 0) {
+ /*
+ * roll back the PWM devices that were disabled by
+ * this suspend function.
+ */
+ pwm_class_resume_npwm(parent, i);
+ break;
+ }
+ }
+
+ return ret;
+}
+
+static int __maybe_unused pwm_class_resume(struct device *parent)
+{
+ struct pwm_chip *chip = dev_get_drvdata(parent);
+
+ return pwm_class_resume_npwm(parent, chip->npwm);
+}
+
+static SIMPLE_DEV_PM_OPS(pwm_class_pm_ops, pwm_class_suspend, pwm_class_resume);
+
static struct class pwm_class = {
.name = "pwm",
.owner = THIS_MODULE,
.dev_groups = pwm_chip_groups,
+ .pm = &pwm_class_pm_ops,
};
static int pwmchip_sysfs_match(struct device *parent, const void *data)
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index eaa5c6e3fc9f..24632a7a7d11 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -405,12 +405,16 @@ struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc,
const struct of_phandle_args *args);
struct pwm_device *pwm_get(struct device *dev, const char *con_id);
-struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id);
+struct pwm_device *of_pwm_get(struct device *dev, struct device_node *np,
+ const char *con_id);
void pwm_put(struct pwm_device *pwm);
struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id);
struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
const char *con_id);
+struct pwm_device *devm_fwnode_pwm_get(struct device *dev,
+ struct fwnode_handle *fwnode,
+ const char *con_id);
void devm_pwm_put(struct device *dev, struct pwm_device *pwm);
#else
static inline struct pwm_device *pwm_request(int pwm_id, const char *label)
@@ -493,7 +497,8 @@ static inline struct pwm_device *pwm_get(struct device *dev,
return ERR_PTR(-ENODEV);
}
-static inline struct pwm_device *of_pwm_get(struct device_node *np,
+static inline struct pwm_device *of_pwm_get(struct device *dev,
+ struct device_node *np,
const char *con_id)
{
return ERR_PTR(-ENODEV);
@@ -516,6 +521,13 @@ static inline struct pwm_device *devm_of_pwm_get(struct device *dev,
return ERR_PTR(-ENODEV);
}
+static inline struct pwm_device *
+devm_fwnode_pwm_get(struct device *dev, struct fwnode_handle *fwnode,
+ const char *con_id)
+{
+ return ERR_PTR(-ENODEV);
+}
+
static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
{
}
generated by cgit v1.2.3 (git 2.39.0) at 2024-10-31 08:18:59 +0300