Merge patch series "led: implement software blinking"
Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu> says:
v2 changes:
* Drop sw_blink_state structure, move its necessary fields to
led_uc_plat structure.
* Add cyclic_info pointer to led_uc_plat structure. This
simplify code a lot.
* Remove cyclic function search logic. Not needed anymore.
* Fix blinking period. It was twice large.
* Other cleanups.
v3 changes:
* Adapt code to recent cyclic function changes
* Move software blinking functions to separate file
* Other small changes
v4 changes:
* Refactoring of led_set_period() function
v5 changes
* Fix compilation if CONFIG_LED_BLINK is not defined
v6 changes:
* Enable LEDST_BLINK state unconditionally.
* Function led_set_period() becomes available when CONFIG_LED_BLINK
is disabled. This makes led code simpler.
* Software blinking requires about 100 bytes of data for a led. It's
not a good idea to allocate so much memory for each supported led.
Change the code to allocate blinking data only for required leds.
diff --git a/cmd/led.c b/cmd/led.c
index 4256b34..2f786f3 100644
--- a/cmd/led.c
+++ b/cmd/led.c
@@ -15,9 +15,7 @@
[LEDST_OFF] = "off",
[LEDST_ON] = "on",
[LEDST_TOGGLE] = "toggle",
-#ifdef CONFIG_LED_BLINK
[LEDST_BLINK] = "blink",
-#endif
};
enum led_state_t get_led_cmd(char *var)
@@ -75,9 +73,7 @@
enum led_state_t cmd;
const char *led_label;
struct udevice *dev;
-#ifdef CONFIG_LED_BLINK
int freq_ms = 0;
-#endif
int ret;
/* Validate arguments */
@@ -88,13 +84,11 @@
return list_leds();
cmd = argc > 2 ? get_led_cmd(argv[2]) : LEDST_COUNT;
-#ifdef CONFIG_LED_BLINK
if (cmd == LEDST_BLINK) {
if (argc < 4)
return CMD_RET_USAGE;
freq_ms = dectoul(argv[3], NULL);
}
-#endif
ret = led_get_by_label(led_label, &dev);
if (ret) {
printf("LED '%s' not found (err=%d)\n", led_label, ret);
@@ -106,13 +100,11 @@
case LEDST_TOGGLE:
ret = led_set_state(dev, cmd);
break;
-#ifdef CONFIG_LED_BLINK
case LEDST_BLINK:
ret = led_set_period(dev, freq_ms);
if (!ret)
ret = led_set_state(dev, LEDST_BLINK);
break;
-#endif
case LEDST_COUNT:
printf("LED '%s': ", led_label);
ret = show_led_state(dev);
diff --git a/drivers/led/Kconfig b/drivers/led/Kconfig
index 9837960..bee74b2 100644
--- a/drivers/led/Kconfig
+++ b/drivers/led/Kconfig
@@ -65,7 +65,7 @@
Linux compatible ofdata.
config LED_BLINK
- bool "Support LED blinking"
+ bool "Support hardware LED blinking"
depends on LED
help
Some drivers can support automatic blinking of LEDs with a given
@@ -73,6 +73,20 @@
This option enables support for this which adds slightly to the
code size.
+config LED_SW_BLINK
+ bool "Support software LED blinking"
+ depends on LED
+ select CYCLIC
+ help
+ Turns on led blinking implemented in the software, useful when
+ the hardware doesn't support led blinking. Half of the period
+ led will be ON and the rest time it will be OFF. Standard
+ led commands can be used to configure blinking. Does nothing
+ if driver supports hardware blinking.
+ WARNING: Blinking may be inaccurate during execution of time
+ consuming commands (ex. flash reading). Also it completely
+ stops during OS booting.
+
config SPL_LED
bool "Enable LED support in SPL"
depends on SPL_DM
diff --git a/drivers/led/Makefile b/drivers/led/Makefile
index 2bcb858..e27aa48 100644
--- a/drivers/led/Makefile
+++ b/drivers/led/Makefile
@@ -4,6 +4,7 @@
# Written by Simon Glass <sjg@chromium.org>
obj-y += led-uclass.o
+obj-$(CONFIG_LED_SW_BLINK) += led_sw_blink.o
obj-$(CONFIG_LED_BCM6328) += led_bcm6328.o
obj-$(CONFIG_LED_BCM6358) += led_bcm6358.o
obj-$(CONFIG_LED_BCM6753) += led_bcm6753.o
diff --git a/drivers/led/led-uclass.c b/drivers/led/led-uclass.c
index f37bf6a..199d68b 100644
--- a/drivers/led/led-uclass.c
+++ b/drivers/led/led-uclass.c
@@ -58,6 +58,10 @@
if (!ops->set_state)
return -ENOSYS;
+ if (IS_ENABLED(CONFIG_LED_SW_BLINK) &&
+ led_sw_on_state_change(dev, state))
+ return 0;
+
return ops->set_state(dev, state);
}
@@ -68,20 +72,27 @@
if (!ops->get_state)
return -ENOSYS;
+ if (IS_ENABLED(CONFIG_LED_SW_BLINK) &&
+ led_sw_is_blinking(dev))
+ return LEDST_BLINK;
+
return ops->get_state(dev);
}
-#ifdef CONFIG_LED_BLINK
int led_set_period(struct udevice *dev, int period_ms)
{
+#ifdef CONFIG_LED_BLINK
struct led_ops *ops = led_get_ops(dev);
- if (!ops->set_period)
- return -ENOSYS;
+ if (ops->set_period)
+ return ops->set_period(dev, period_ms);
+#endif
+
+ if (IS_ENABLED(CONFIG_LED_SW_BLINK))
+ return led_sw_set_period(dev, period_ms);
- return ops->set_period(dev, period_ms);
+ return -ENOSYS;
}
-#endif
static int led_post_bind(struct udevice *dev)
{
@@ -107,6 +118,14 @@
else
return 0;
+ if (IS_ENABLED(CONFIG_LED_BLINK)) {
+ const char *trigger;
+
+ trigger = dev_read_string(dev, "linux,default-trigger");
+ if (trigger && !strncmp(trigger, "pattern", 7))
+ uc_plat->default_state = LEDST_BLINK;
+ }
+
/*
* In case the LED has default-state DT property, trigger
* probe() to configure its default state during startup.
@@ -119,12 +138,24 @@
static int led_post_probe(struct udevice *dev)
{
struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
+ int default_period_ms = 1000;
+ int ret = 0;
- if (uc_plat->default_state == LEDST_ON ||
- uc_plat->default_state == LEDST_OFF)
- led_set_state(dev, uc_plat->default_state);
+ switch (uc_plat->default_state) {
+ case LEDST_ON:
+ case LEDST_OFF:
+ ret = led_set_state(dev, uc_plat->default_state);
+ break;
+ case LEDST_BLINK:
+ ret = led_set_period(dev, default_period_ms);
+ if (!ret)
+ ret = led_set_state(dev, uc_plat->default_state);
+ break;
+ default:
+ break;
+ }
- return 0;
+ return ret;
}
UCLASS_DRIVER(led) = {
diff --git a/drivers/led/led_sw_blink.c b/drivers/led/led_sw_blink.c
new file mode 100644
index 0000000..9e36edb
--- /dev/null
+++ b/drivers/led/led_sw_blink.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Software blinking helpers
+ * Copyright (C) 2024 IOPSYS Software Solutions AB
+ * Author: Mikhail Kshevetskiy <mikhail.kshevetskiy@iopsys.eu>
+ */
+
+#include <dm.h>
+#include <led.h>
+#include <time.h>
+#include <stdlib.h>
+
+#define CYCLIC_NAME_PREFIX "led_sw_blink_"
+
+static void led_sw_blink(struct cyclic_info *c)
+{
+ struct led_sw_blink *sw_blink;
+ struct udevice *dev;
+ struct led_ops *ops;
+
+ sw_blink = container_of(c, struct led_sw_blink, cyclic);
+ dev = sw_blink->dev;
+ ops = led_get_ops(dev);
+
+ switch (sw_blink->state) {
+ case LED_SW_BLINK_ST_OFF:
+ sw_blink->state = LED_SW_BLINK_ST_ON;
+ ops->set_state(dev, LEDST_ON);
+ break;
+ case LED_SW_BLINK_ST_ON:
+ sw_blink->state = LED_SW_BLINK_ST_OFF;
+ ops->set_state(dev, LEDST_OFF);
+ break;
+ case LED_SW_BLINK_ST_NOT_READY:
+ /*
+ * led_set_period has been called, but
+ * led_set_state(LDST_BLINK) has not yet,
+ * so doing nothing
+ */
+ break;
+ default:
+ break;
+ }
+}
+
+int led_sw_set_period(struct udevice *dev, int period_ms)
+{
+ struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
+ struct led_sw_blink *sw_blink = uc_plat->sw_blink;
+ struct led_ops *ops = led_get_ops(dev);
+ int half_period_us;
+
+ half_period_us = period_ms * 1000 / 2;
+
+ if (!sw_blink) {
+ int len = sizeof(struct led_sw_blink) +
+ strlen(CYCLIC_NAME_PREFIX) +
+ strlen(uc_plat->label) + 1;
+
+ sw_blink = calloc(1, len);
+ if (!sw_blink)
+ return -ENOMEM;
+
+ sw_blink->dev = dev;
+ sw_blink->state = LED_SW_BLINK_ST_DISABLED;
+ strcpy((char *)sw_blink->cyclic_name, CYCLIC_NAME_PREFIX);
+ strcat((char *)sw_blink->cyclic_name, uc_plat->label);
+
+ uc_plat->sw_blink = sw_blink;
+ }
+
+ if (sw_blink->state == LED_SW_BLINK_ST_DISABLED) {
+ cyclic_register(&sw_blink->cyclic, led_sw_blink,
+ half_period_us, sw_blink->cyclic_name);
+ } else {
+ sw_blink->cyclic.delay_us = half_period_us;
+ sw_blink->cyclic.start_time_us = timer_get_us();
+ }
+
+ sw_blink->state = LED_SW_BLINK_ST_NOT_READY;
+ ops->set_state(dev, LEDST_OFF);
+
+ return 0;
+}
+
+bool led_sw_is_blinking(struct udevice *dev)
+{
+ struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
+ struct led_sw_blink *sw_blink = uc_plat->sw_blink;
+
+ if (!sw_blink)
+ return false;
+
+ return sw_blink->state > LED_SW_BLINK_ST_NOT_READY;
+}
+
+bool led_sw_on_state_change(struct udevice *dev, enum led_state_t state)
+{
+ struct led_uc_plat *uc_plat = dev_get_uclass_plat(dev);
+ struct led_sw_blink *sw_blink = uc_plat->sw_blink;
+
+ if (!sw_blink || sw_blink->state == LED_SW_BLINK_ST_DISABLED)
+ return false;
+
+ if (state == LEDST_BLINK) {
+ /* start blinking on next led_sw_blink() call */
+ sw_blink->state = LED_SW_BLINK_ST_OFF;
+ return true;
+ }
+
+ /* stop blinking */
+ uc_plat->sw_blink = NULL;
+ cyclic_unregister(&sw_blink->cyclic);
+ free(sw_blink);
+
+ return false;
+}
diff --git a/include/led.h b/include/led.h
index a635316..99f93c5 100644
--- a/include/led.h
+++ b/include/led.h
@@ -7,19 +7,34 @@
#ifndef __LED_H
#define __LED_H
+#include <stdbool.h>
+#include <cyclic.h>
+
struct udevice;
enum led_state_t {
LEDST_OFF = 0,
LEDST_ON = 1,
LEDST_TOGGLE,
-#ifdef CONFIG_LED_BLINK
LEDST_BLINK,
-#endif
LEDST_COUNT,
};
+enum led_sw_blink_state_t {
+ LED_SW_BLINK_ST_DISABLED,
+ LED_SW_BLINK_ST_NOT_READY,
+ LED_SW_BLINK_ST_OFF,
+ LED_SW_BLINK_ST_ON,
+};
+
+struct led_sw_blink {
+ enum led_sw_blink_state_t state;
+ struct udevice *dev;
+ struct cyclic_info cyclic;
+ const char cyclic_name[0];
+};
+
/**
* struct led_uc_plat - Platform data the uclass stores about each device
*
@@ -29,6 +44,9 @@
struct led_uc_plat {
const char *label;
enum led_state_t default_state;
+#ifdef CONFIG_LED_SW_BLINK
+ struct led_sw_blink *sw_blink;
+#endif
};
/**
@@ -118,4 +136,9 @@
*/
int led_bind_generic(struct udevice *parent, const char *driver_name);
+/* Internal functions for software blinking. Do not use them in your code */
+int led_sw_set_period(struct udevice *dev, int period_ms);
+bool led_sw_is_blinking(struct udevice *dev);
+bool led_sw_on_state_change(struct udevice *dev, enum led_state_t state);
+
#endif