This patch add the support of PWM controller which can be found at aspeed
ast2600 soc. The pwm supoorts up to 16 channels and it's part function
of multi-function device "pwm-tach controller".
Signed-off-by: Billy Tsai <[email protected]>
---
drivers/pwm/Kconfig | 10 +
drivers/pwm/Makefile | 1 +
drivers/pwm/pwm-aspeed-ast2600.c | 327 +++++++++++++++++++++++++++++++
3 files changed, 338 insertions(+)
create mode 100644 drivers/pwm/pwm-aspeed-ast2600.c
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 63be5362fd3a..b0d26f6c2a8f 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -51,6 +51,16 @@ config PWM_AB8500
To compile this driver as a module, choose M here: the module
will be called pwm-ab8500.
+config PWM_ASPEED_AST2600
+ tristate "Aspeed ast2600 PWM support"
+ depends on ARCH_ASPEED || COMPILE_TEST
+ depends on HAVE_CLK && HAS_IOMEM
+ help
+ This driver provides support for Aspeed ast2600 PWM controllers.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-aspeed-ast2600.
+
config PWM_ATMEL
tristate "Atmel PWM support"
depends on OF
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index cbdcd55d69ee..ada454f9129a 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -2,6 +2,7 @@
obj-$(CONFIG_PWM) += core.o
obj-$(CONFIG_PWM_SYSFS) += sysfs.o
obj-$(CONFIG_PWM_AB8500) += pwm-ab8500.o
+obj-$(CONFIG_PWM_ASPEED_AST2600) += pwm-aspeed-ast2600.o
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
diff --git a/drivers/pwm/pwm-aspeed-ast2600.c b/drivers/pwm/pwm-aspeed-ast2600.c
new file mode 100644
index 000000000000..34fa5800db4d
--- /dev/null
+++ b/drivers/pwm/pwm-aspeed-ast2600.c
@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2021 Aspeed Technology Inc.
+ *
+ * PWM controller driver for Aspeed ast2600 SoCs.
+ * This drivers doesn't support earlier version of the IP.
+ *
+ * The hardware operates in time quantities of length
+ * Q := (DIV_L + 1) << DIV_H / input-clk
+ * The length of a PWM period is (DUTY_CYCLE_PERIOD + 1) * Q.
+ * The maximal value for DUTY_CYCLE_PERIOD is used here to provide
+ * a fine grained selection for the duty cycle.
+ *
+ * This driver uses DUTY_CYCLE_RISING_POINT = 0, so from the start of a
+ * period the output is active until DUTY_CYCLE_FALLING_POINT * Q. Note
+ * that if DUTY_CYCLE_RISING_POINT = DUTY_CYCLE_FALLING_POINT the output is
+ * always active.
+ *
+ * Register usage:
+ * PIN_ENABLE: When it is unset the pwm controller will emit inactive level to the external.
+ * Use to determine whether the PWM channel is enabled or disabled
+ * CLK_ENABLE: When it is unset the pwm controller will assert the duty counter reset and
+ * emit inactive level to the PIN_ENABLE mux after that the driver can still change the pwm period
+ * and duty and the value will apply when CLK_ENABLE be set again.
+ * Use to determine whether duty_cycle bigger than 0.
+ * PWM_ASPEED_CTRL_INVERSE: When it is toggled the output value will inverse immediately.
+ * PWM_ASPEED_DUTY_CYCLE_FALLING_POINT/PWM_ASPEED_DUTY_CYCLE_RISING_POINT: When these two
+ * values are equal it means the duty cycle = 100%.
+ *
+ * The glitch may generate at:
+ * - Enabled changing when the duty_cycle bigger than 0% and less than 100%.
+ * - Polarity changing when the duty_cycle bigger than 0% and less than 100%.
+ *
+ * Limitations:
+ * - When changing both duty cycle and period, we cannot prevent in
+ * software that the output might produce a period with mixed
+ * settings.
+ * - Disabling the PWM doesn't complete the current period.
+ *
+ * Improvements:
+ * - When only changing one of duty cycle or period, our pwm controller will not
+ * generate the glitch, the configure will change at next cycle of pwm.
+ * This improvement can disable/enable through PWM_ASPEED_CTRL_DUTY_SYNC_DISABLE.
+ */
+
+#include <linux/clk.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/sysfs.h>
+#include <linux/reset.h>
+#include <linux/regmap.h>
+#include <linux/bitfield.h>
+#include <linux/slab.h>
+#include <linux/pwm.h>
+#include <linux/math64.h>
+
+/* The channel number of Aspeed pwm controller */
+#define PWM_ASPEED_NR_PWMS 16
+
+/* PWM Control Register */
+#define PWM_ASPEED_CTRL(ch) ((ch) * 0x10 + 0x00)
+#define PWM_ASPEED_CTRL_LOAD_SEL_RISING_AS_WDT BIT(19)
+#define PWM_ASPEED_CTRL_DUTY_LOAD_AS_WDT_ENABLE BIT(18)
+#define PWM_ASPEED_CTRL_DUTY_SYNC_DISABLE BIT(17)
+#define PWM_ASPEED_CTRL_CLK_ENABLE BIT(16)
+#define PWM_ASPEED_CTRL_LEVEL_OUTPUT BIT(15)
+#define PWM_ASPEED_CTRL_INVERSE BIT(14)
+#define PWM_ASPEED_CTRL_OPEN_DRAIN_ENABLE BIT(13)
+#define PWM_ASPEED_CTRL_PIN_ENABLE BIT(12)
+#define PWM_ASPEED_CTRL_CLK_DIV_H GENMASK(11, 8)
+#define PWM_ASPEED_CTRL_CLK_DIV_L GENMASK(7, 0)
+
+/* PWM Duty Cycle Register */
+#define PWM_ASPEED_DUTY_CYCLE(ch) ((ch) * 0x10 + 0x04)
+#define PWM_ASPEED_DUTY_CYCLE_PERIOD GENMASK(31, 24)
+#define PWM_ASPEED_DUTY_CYCLE_POINT_AS_WDT GENMASK(23, 16)
+#define PWM_ASPEED_DUTY_CYCLE_FALLING_POINT GENMASK(15, 8)
+#define PWM_ASPEED_DUTY_CYCLE_RISING_POINT GENMASK(7, 0)
+
+/* PWM fixed value */
+#define PWM_ASPEED_FIXED_PERIOD FIELD_MAX(PWM_ASPEED_DUTY_CYCLE_PERIOD)
+
+struct aspeed_pwm_data {
+ struct pwm_chip chip;
+ struct clk *clk;
+ struct regmap *regmap;
+ struct reset_control *reset;
+};
+
+static inline struct aspeed_pwm_data *
+aspeed_pwm_chip_to_data(struct pwm_chip *chip)
+{
+ return container_of(chip, struct aspeed_pwm_data, chip);
+}
+
+static void aspeed_pwm_get_state(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ struct device *dev = chip->dev;
+ struct aspeed_pwm_data *priv = aspeed_pwm_chip_to_data(chip);
+ u32 hwpwm = pwm->hwpwm;
+ bool polarity, pin_en, clk_en;
+ u32 duty_pt, val;
+ unsigned long rate;
+ u64 div_h, div_l, duty_cycle_period, dividend;
+
+ regmap_read(priv->regmap, PWM_ASPEED_CTRL(hwpwm), &val);
+ polarity = FIELD_GET(PWM_ASPEED_CTRL_INVERSE, val);
+ pin_en = FIELD_GET(PWM_ASPEED_CTRL_PIN_ENABLE, val);
+ clk_en = FIELD_GET(PWM_ASPEED_CTRL_CLK_ENABLE, val);
+ div_h = FIELD_GET(PWM_ASPEED_CTRL_CLK_DIV_H, val);
+ div_l = FIELD_GET(PWM_ASPEED_CTRL_CLK_DIV_L, val);
+ regmap_read(priv->regmap, PWM_ASPEED_DUTY_CYCLE(hwpwm), &val);
+ duty_pt = FIELD_GET(PWM_ASPEED_DUTY_CYCLE_FALLING_POINT, val);
+ duty_cycle_period = FIELD_GET(PWM_ASPEED_DUTY_CYCLE_PERIOD, val);
+
+ rate = clk_get_rate(priv->clk);
+
+ /*
+ * This multiplication doesn't overflow, the upper bound is
+ * 1000000000 * 256 * 256 << 15 = 0x1dcd650000000000
+ */
+ dividend = (u64)NSEC_PER_SEC * (div_l + 1) * (duty_cycle_period + 1)
+ << div_h;
+ state->period = DIV_ROUND_UP_ULL(dividend, rate);
+
+ if (clk_en && duty_pt) {
+ dividend = (u64)NSEC_PER_SEC * (div_l + 1) * duty_pt
+ << div_h;
+ state->duty_cycle = DIV_ROUND_UP_ULL(dividend, rate);
+ } else
+ state->duty_cycle = clk_en ? state->period : 0;
+ state->polarity = polarity ? PWM_POLARITY_INVERSED : PWM_POLARITY_NORMAL;
+ state->enabled = pin_en;
+ dev_dbg(dev, "get period: %lldns, duty_cycle: %lldns", state->period,
+ state->duty_cycle);
+}
+
+static int aspeed_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct device *dev = chip->dev;
+ struct aspeed_pwm_data *priv = aspeed_pwm_chip_to_data(chip);
+ u32 hwpwm = pwm->hwpwm, duty_pt;
+ unsigned long rate;
+ u64 div_h, div_l, divisor, expect_period;
+ bool clk_en;
+
+ expect_period = state->period;
+ dev_dbg(dev, "expect period: %lldns, duty_cycle: %lldns", expect_period,
+ state->duty_cycle);
+
+ rate = clk_get_rate(priv->clk);
+ if (expect_period > div64_u64(ULLONG_MAX, (u64)rate))
+ expect_period = div64_u64(ULLONG_MAX, (u64)rate);
+ /*
+ * Pick the smallest value for div_h so that div_l can be the biggest
+ * which results in a finer resolution near the target period value.
+ */
+ divisor = (u64)NSEC_PER_SEC * (PWM_ASPEED_FIXED_PERIOD + 1) *
+ (FIELD_MAX(PWM_ASPEED_CTRL_CLK_DIV_L) + 1);
+ div_h = order_base_2(DIV64_U64_ROUND_UP(rate * expect_period, divisor));
+ if (div_h > 0xf)
+ div_h = 0xf;
+
+ divisor = ((u64)NSEC_PER_SEC * (PWM_ASPEED_FIXED_PERIOD + 1)) << div_h;
+ div_l = div64_u64(rate * expect_period, divisor);
+
+ if (div_l == 0)
+ return -ERANGE;
+
+ div_l -= 1;
+
+ if (div_l > 255)
+ div_l = 255;
+
+ dev_dbg(dev, "clk source: %ld div_h %lld, div_l : %lld\n", rate, div_h,
+ div_l);
+ /* duty_pt = duty_cycle * (PERIOD + 1) / period */
+ duty_pt = div64_u64(state->duty_cycle * rate,
+ (u64)NSEC_PER_SEC * (div_l + 1) << div_h);
+ dev_dbg(dev, "duty_cycle = %lld, duty_pt = %d\n", state->duty_cycle,
+ duty_pt);
+
+ /*
+ * Fixed DUTY_CYCLE_PERIOD to its max value to get a
+ * fine-grained resolution for duty_cycle at the expense of a
+ * coarser period resolution.
+ */
+ regmap_update_bits(priv->regmap, PWM_ASPEED_DUTY_CYCLE(hwpwm),
+ PWM_ASPEED_DUTY_CYCLE_PERIOD,
+ FIELD_PREP(PWM_ASPEED_DUTY_CYCLE_PERIOD,
+ PWM_ASPEED_FIXED_PERIOD));
+ if (duty_pt == 0)
+ /* emit inactive level and assert the duty counter reset */
+ clk_en = 0;
+ else {
+ clk_en = 1;
+ if (duty_pt >= (PWM_ASPEED_FIXED_PERIOD + 1))
+ duty_pt = 0;
+ regmap_update_bits(
+ priv->regmap, PWM_ASPEED_DUTY_CYCLE(hwpwm),
+ PWM_ASPEED_DUTY_CYCLE_RISING_POINT |
+ PWM_ASPEED_DUTY_CYCLE_FALLING_POINT,
+ FIELD_PREP(PWM_ASPEED_DUTY_CYCLE_FALLING_POINT,
+ duty_pt));
+ }
+
+ regmap_update_bits(
+ priv->regmap, PWM_ASPEED_CTRL(hwpwm),
+ PWM_ASPEED_CTRL_CLK_DIV_H | PWM_ASPEED_CTRL_CLK_DIV_L |
+ PWM_ASPEED_CTRL_PIN_ENABLE |
+ PWM_ASPEED_CTRL_CLK_ENABLE | PWM_ASPEED_CTRL_INVERSE,
+ FIELD_PREP(PWM_ASPEED_CTRL_CLK_DIV_H, div_h) |
+ FIELD_PREP(PWM_ASPEED_CTRL_CLK_DIV_L, div_l) |
+ FIELD_PREP(PWM_ASPEED_CTRL_PIN_ENABLE, state->enabled) |
+ FIELD_PREP(PWM_ASPEED_CTRL_CLK_ENABLE, clk_en) |
+ FIELD_PREP(PWM_ASPEED_CTRL_INVERSE, state->polarity));
+ return 0;
+}
+
+static const struct pwm_ops aspeed_pwm_ops = {
+ .apply = aspeed_pwm_apply,
+ .get_state = aspeed_pwm_get_state,
+ .owner = THIS_MODULE,
+};
+
+static int aspeed_pwm_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ int ret;
+ struct aspeed_pwm_data *priv;
+ struct device_node *np;
+ struct platform_device *parent_dev;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ np = pdev->dev.parent->of_node;
+ if (!of_device_is_compatible(np, "aspeed,ast2600-pwm-tach"))
+ return dev_err_probe(dev, -ENODEV,
+ "Unsupported pwm device binding\n");
+
+ priv->regmap = syscon_node_to_regmap(np);
+ if (IS_ERR(priv->regmap))
+ return dev_err_probe(dev, PTR_ERR(priv->regmap),
+ "Couldn't get regmap\n");
+
+ parent_dev = of_find_device_by_node(np);
+ priv->clk = devm_clk_get(&parent_dev->dev, 0);
+ if (IS_ERR(priv->clk))
+ return dev_err_probe(dev, PTR_ERR(priv->clk),
+ "Couldn't get clock\n");
+
+ priv->reset = devm_reset_control_get_shared(&parent_dev->dev, NULL);
+ if (IS_ERR(priv->reset))
+ return dev_err_probe(dev, PTR_ERR(priv->reset),
+ "Couldn't get reset control\n");
+
+ ret = clk_prepare_enable(priv->clk);
+ if (ret)
+ return dev_err_probe(dev, ret, "Couldn't enable clock\n");
+
+ ret = reset_control_deassert(priv->reset);
+ if (ret) {
+ dev_err_probe(dev, ret, "Couldn't deassert reset control\n");
+ goto err_disable_clk;
+ }
+
+ priv->chip.dev = dev;
+ priv->chip.ops = &aspeed_pwm_ops;
+ priv->chip.npwm = PWM_ASPEED_NR_PWMS;
+
+ ret = pwmchip_add(&priv->chip);
+ if (ret < 0) {
+ dev_err_probe(dev, ret, "Failed to add PWM chip\n");
+ goto err_assert_reset;
+ }
+ dev_set_drvdata(dev, priv);
+ return 0;
+err_assert_reset:
+ reset_control_assert(priv->reset);
+err_disable_clk:
+ clk_disable_unprepare(priv->clk);
+ return ret;
+}
+
+static int aspeed_pwm_remove(struct platform_device *dev)
+{
+ struct aspeed_pwm_data *priv = platform_get_drvdata(dev);
+
+ pwmchip_remove(&priv->chip);
+ reset_control_assert(priv->reset);
+ clk_disable_unprepare(priv->clk);
+
+ return 0;
+}
+
+static const struct of_device_id of_pwm_match_table[] = {
+ {
+ .compatible = "aspeed,ast2600-pwm",
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, of_pwm_match_table);
+
+static struct platform_driver aspeed_pwm_driver = {
+ .probe = aspeed_pwm_probe,
+ .remove = aspeed_pwm_remove,
+ .driver = {
+ .name = "aspeed-pwm",
+ .of_match_table = of_pwm_match_table,
+ },
+};
+
+module_platform_driver(aspeed_pwm_driver);
+
+MODULE_AUTHOR("Billy Tsai <[email protected]>");
+MODULE_DESCRIPTION("Aspeed ast2600 PWM device driver");
+MODULE_LICENSE("GPL v2");
--
2.25.1
Hello Billy,
just two minor thing left to criticise:
On Mon, Nov 29, 2021 at 02:43:29PM +0800, Billy Tsai wrote:
> + if (clk_en && duty_pt) {
> + dividend = (u64)NSEC_PER_SEC * (div_l + 1) * duty_pt
> + << div_h;
> + state->duty_cycle = DIV_ROUND_UP_ULL(dividend, rate);
> + } else
> + state->duty_cycle = clk_en ? state->period : 0;
I wonder about checkpatch not criticising this construct. See
Documentation/process/coding-style.rst:
Do not unnecessarily use braces where a single statement will
do. [...] This does not apply if only one branch of a
conditional statement is a single statement; in the latter case
use braces in both branches
> [...]
> +static int aspeed_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
> + const struct pwm_state *state)
> +{
> + struct device *dev = chip->dev;
> + struct aspeed_pwm_data *priv = aspeed_pwm_chip_to_data(chip);
> + u32 hwpwm = pwm->hwpwm, duty_pt;
> + unsigned long rate;
> + u64 div_h, div_l, divisor, expect_period;
> + bool clk_en;
> +
> + expect_period = state->period;
> + dev_dbg(dev, "expect period: %lldns, duty_cycle: %lldns", expect_period,
> + state->duty_cycle);
> +
> + rate = clk_get_rate(priv->clk);
> + if (expect_period > div64_u64(ULLONG_MAX, (u64)rate))
> + expect_period = div64_u64(ULLONG_MAX, (u64)rate);
If you write that as
expect_period = min(div64_u64(ULLONG_MAX, (u64)rate), expect_period);
you make sure that the division is only calculated once.
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-K?nig |
Industrial Linux Solutions | https://www.pengutronix.de/ |
On Mon, 2021-11-29 at 14:43 +0800, Billy Tsai wrote:
[...]
> + ret = clk_prepare_enable(priv->clk);
> + if (ret)
> + return dev_err_probe(dev, ret, "Couldn't enable clock\n");
> +
> + ret = reset_control_deassert(priv->reset);
> + if (ret) {
> + dev_err_probe(dev, ret, "Couldn't deassert reset control\n");
> + goto err_disable_clk;
> + }
Is there any reason to keep the clocks running and the controller out of
reset while the PWM outputs are disabled?
regards
Philipp
Hi Philipp,
On 2021/11/30, 5:52 PM, "Philipp Zabel" <[email protected]> wrote:
On Mon, 2021-11-29 at 14:43 +0800, Billy Tsai wrote:
[...]
> > + ret = clk_prepare_enable(priv->clk);
> > + if (ret)
> > + return dev_err_probe(dev, ret, "Couldn't enable clock\n");
> > +
> > + ret = reset_control_deassert(priv->reset);
> > + if (ret) {
> > + dev_err_probe(dev, ret, "Couldn't deassert reset control\n");
> > + goto err_disable_clk;
> > + }
> Is there any reason to keep the clocks running and the controller out of
> reset while the PWM outputs are disabled?
Can you tell me about your concerns with this process?
In my opinion, they are used to provide the clock and de-assert the reset of the PWM engine. If we didn't release
them in probe stage the CPU can't and shouldn't read the register of the PWM engine when call the get_state.
Assume that we want to adjust them dynamically, the driver needs to add more conditions to check and keep the status
of each PWM channel, which is not a good deal for the server platform.
Thanks
Best Regards,
Billy Tsai
Hi Billy,
On Wed, 2021-12-01 at 03:30 +0000, Billy Tsai wrote:
> Hi Philipp,
>
> On 2021/11/30, 5:52 PM, "Philipp Zabel" <[email protected]> wrote:
>
> On Mon, 2021-11-29 at 14:43 +0800, Billy Tsai wrote:
> [...]
> > > + ret = clk_prepare_enable(priv->clk);
> > > + if (ret)
> > > + return dev_err_probe(dev, ret, "Couldn't enable clock\n");
> > > +
> > > + ret = reset_control_deassert(priv->reset);
> > > + if (ret) {
> > > + dev_err_probe(dev, ret, "Couldn't deassert reset control\n");
> > > + goto err_disable_clk;
> > > + }
>
> > Is there any reason to keep the clocks running and the controller out of
> > reset while the PWM outputs are disabled?
>
> Can you tell me about your concerns with this process?
No particular concerns, just curiosity.
> In my opinion, they are used to provide the clock and de-assert the reset of the PWM engine. If we didn't release
> them in probe stage the CPU can't and shouldn't read the register of the PWM engine when call the get_state.
> Assume that we want to adjust them dynamically, the driver needs to add more conditions to check and keep the status
> of each PWM channel, which is not a good deal for the server platform.
Thanks. I don't know the hardware, so I have no idea whether disabling
the clocks would even save a measurable (let alone appreciable) amount
of power.
I've just seen other PWM drivers use runtime PM or enable/disable clocks
dynamically, and wondered why this one doesn't.
regards
Philipp
Hi Philipp,
On 2021/12/1, 5:12 PM, "Philipp Zabel" <[email protected]> wrote:
Hi Billy,
On Wed, 2021-12-01 at 03:30 +0000, Billy Tsai wrote:
> > Hi Philipp,
> >
> > On 2021/11/30, 5:52 PM, "Philipp Zabel" <[email protected]> wrote:
> >
> > On Mon, 2021-11-29 at 14:43 +0800, Billy Tsai wrote:
> > [...]
> > > > + ret = clk_prepare_enable(priv->clk);
> > > > + if (ret)
> > > > + return dev_err_probe(dev, ret, "Couldn't enable clock\n");
> > > > +
> > > > + ret = reset_control_deassert(priv->reset);
> > > > + if (ret) {
> > > > + dev_err_probe(dev, ret, "Couldn't deassert reset control\n");
> > > > + goto err_disable_clk;
> > > > + }
> >
> > > Is there any reason to keep the clocks running and the controller out of
> > > reset while the PWM outputs are disabled?
> >
> > Can you tell me about your concerns with this process?
> No particular concerns, just curiosity.
> > In my opinion, they are used to provide the clock and de-assert the reset of the PWM engine. If we didn't release
> > them in probe stage the CPU can't and shouldn't read the register of the PWM engine when call the get_state.
> > Assume that we want to adjust them dynamically, the driver needs to add more conditions to check and keep the status
> > of each PWM channel, which is not a good deal for the server platform.
> Thanks. I don't know the hardware, so I have no idea whether disabling
> the clocks would even save a measurable (let alone appreciable) amount
> of power.
> I've just seen other PWM drivers use runtime PM or enable/disable clocks
> dynamically, and wondered why this one doesn't.
Thanks for the heads up, I think that for the usage we don't need to implement that.
Best Regards,
Billy Tsai