From: ChiYuan Huang <[email protected]>
The MT6370 is a highly-integrated smart power management IC, which
includes a single cell Li-Ion/Li-Polymer switching battery charger,
a USB Type-C & Power Delivery (PD) controller, dual Flash LED current
sources, a RGB LED driver, a backlight WLED driver, a display bias
driver and a general LDO for portable devices.
This commit add support for the Type-C & Power Delivery controller in
MediaTek MT6370 IC.
Signed-off-by: ChiYuan Huang <[email protected]>
---
v5
- Add comma for the last index of mt6370_reg_init.
- Use dev_err_probe to decrease LOC.
- Use 'dev' variable to make probe function more clean.
- Refine kconfig text.
- Remove both 'else' in set_vbus callback.
- Remove comma for of_device_id if the assigned member is only one.
---
drivers/usb/typec/tcpm/Kconfig | 11 ++
drivers/usb/typec/tcpm/Makefile | 1 +
drivers/usb/typec/tcpm/tcpci_mt6370.c | 207 ++++++++++++++++++++++++++++++++++
3 files changed, 219 insertions(+)
create mode 100644 drivers/usb/typec/tcpm/tcpci_mt6370.c
diff --git a/drivers/usb/typec/tcpm/Kconfig b/drivers/usb/typec/tcpm/Kconfig
index 073fd2e..e6b88ca 100644
--- a/drivers/usb/typec/tcpm/Kconfig
+++ b/drivers/usb/typec/tcpm/Kconfig
@@ -35,6 +35,17 @@ config TYPEC_MT6360
USB Type-C. It works with Type-C Port Controller Manager
to provide USB PD and USB Type-C functionalities.
+config TYPEC_TCPCI_MT6370
+ tristate "MediaTek MT6370 Type-C driver"
+ depends on MFD_MT6370
+ help
+ MediaTek MT6370 is a multi-functional IC that includes
+ USB Type-C. It works with Type-C Port Controller Manager
+ to provide USB PD and USB Type-C functionalities.
+
+ This driver can also be built as a module. The module
+ will be called "tcpci_mt6370".
+
config TYPEC_TCPCI_MAXIM
tristate "Maxim TCPCI based Type-C chip driver"
help
diff --git a/drivers/usb/typec/tcpm/Makefile b/drivers/usb/typec/tcpm/Makefile
index 7d499f3..906d9dc 100644
--- a/drivers/usb/typec/tcpm/Makefile
+++ b/drivers/usb/typec/tcpm/Makefile
@@ -6,4 +6,5 @@ typec_wcove-y := wcove.o
obj-$(CONFIG_TYPEC_TCPCI) += tcpci.o
obj-$(CONFIG_TYPEC_RT1711H) += tcpci_rt1711h.o
obj-$(CONFIG_TYPEC_MT6360) += tcpci_mt6360.o
+obj-$(CONFIG_TYPEC_TCPCI_MT6370) += tcpci_mt6370.o
obj-$(CONFIG_TYPEC_TCPCI_MAXIM) += tcpci_maxim.o
diff --git a/drivers/usb/typec/tcpm/tcpci_mt6370.c b/drivers/usb/typec/tcpm/tcpci_mt6370.c
new file mode 100644
index 0000000..a08b0ba
--- /dev/null
+++ b/drivers/usb/typec/tcpm/tcpci_mt6370.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2022 Richtek Technology Corp.
+ *
+ * Author: ChiYuan Huang <[email protected]>
+ */
+
+#include <linux/bits.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm_wakeup.h>
+#include <linux/pm_wakeirq.h>
+#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
+#include <linux/usb/tcpm.h>
+#include "tcpci.h"
+
+#define MT6370_REG_SYSCTRL8 0x9B
+
+#define MT6370_AUTOIDLE_MASK BIT(3)
+
+#define MT6370_VENDOR_ID 0x29CF
+#define MT6370_TCPC_DID_A 0x2170
+
+struct mt6370_priv {
+ struct device *dev;
+ struct regulator *vbus;
+ struct tcpci *tcpci;
+ struct tcpci_data tcpci_data;
+ int irq;
+};
+
+static const struct reg_sequence mt6370_reg_init[] = {
+ REG_SEQ(0xA0, 0x1, 1000),
+ REG_SEQ(0x81, 0x38, 0),
+ REG_SEQ(0x82, 0x82, 0),
+ REG_SEQ(0xBA, 0xFC, 0),
+ REG_SEQ(0xBB, 0x50, 0),
+ REG_SEQ(0x9E, 0x8F, 0),
+ REG_SEQ(0xA1, 0x5, 0),
+ REG_SEQ(0xA2, 0x4, 0),
+ REG_SEQ(0xA3, 0x4A, 0),
+ REG_SEQ(0xA4, 0x01, 0),
+ REG_SEQ(0x95, 0x01, 0),
+ REG_SEQ(0x80, 0x71, 0),
+ REG_SEQ(0x9B, 0x3A, 1000),
+};
+
+static int mt6370_tcpc_init(struct tcpci *tcpci, struct tcpci_data *data)
+{
+ u16 did;
+ int ret;
+
+ ret = regmap_register_patch(data->regmap, mt6370_reg_init,
+ ARRAY_SIZE(mt6370_reg_init));
+ if (ret)
+ return ret;
+
+ ret = regmap_raw_read(data->regmap, TCPC_BCD_DEV, &did, sizeof(u16));
+ if (ret)
+ return ret;
+
+ if (did == MT6370_TCPC_DID_A)
+ return regmap_write(data->regmap, TCPC_FAULT_CTRL, 0x80);
+
+ return 0;
+}
+
+static int mt6370_tcpc_set_vconn(struct tcpci *tcpci, struct tcpci_data *data,
+ bool enable)
+{
+ return regmap_update_bits(data->regmap, MT6370_REG_SYSCTRL8,
+ MT6370_AUTOIDLE_MASK,
+ !enable ? MT6370_AUTOIDLE_MASK : 0);
+}
+
+static int mt6370_tcpc_set_vbus(struct tcpci *tcpci, struct tcpci_data *data,
+ bool source, bool sink)
+{
+ struct mt6370_priv *priv = container_of(data, struct mt6370_priv,
+ tcpci_data);
+ int ret;
+
+ ret = regulator_is_enabled(priv->vbus);
+ if (ret < 0)
+ return ret;
+
+ if (ret && !source)
+ return regulator_disable(priv->vbus);
+
+ if (!ret && source)
+ return regulator_enable(priv->vbus);
+
+ return 0;
+}
+
+static irqreturn_t mt6370_irq_handler(int irq, void *dev_id)
+{
+ struct mt6370_priv *priv = dev_id;
+
+ return tcpci_irq(priv->tcpci);
+}
+
+static int mt6370_check_vendor_info(struct mt6370_priv *priv)
+{
+ struct regmap *regmap = priv->tcpci_data.regmap;
+ u16 vid;
+ int ret;
+
+ ret = regmap_raw_read(regmap, TCPC_VENDOR_ID, &vid, sizeof(u16));
+ if (ret)
+ return ret;
+
+ if (vid != MT6370_VENDOR_ID)
+ return dev_err_probe(priv->dev, -ENODEV,
+ "Vendor ID not correct 0x%02x\n", vid);
+
+ return 0;
+}
+
+static int mt6370_tcpc_probe(struct platform_device *pdev)
+{
+ struct mt6370_priv *priv;
+ struct device *dev = &pdev->dev;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->dev = dev;
+ platform_set_drvdata(pdev, priv);
+
+ priv->tcpci_data.regmap = dev_get_regmap(dev->parent, NULL);
+ if (!priv->tcpci_data.regmap)
+ return dev_err_probe(dev, -ENODEV, "Failed to init regmap\n");
+
+ ret = mt6370_check_vendor_info(priv);
+ if (ret)
+ return ret;
+
+ priv->irq = platform_get_irq(pdev, 0);
+ if (priv->irq < 0)
+ return priv->irq;
+
+ /* Assign TCPCI feature and ops */
+ priv->tcpci_data.auto_discharge_disconnect = 1;
+ priv->tcpci_data.init = mt6370_tcpc_init;
+ priv->tcpci_data.set_vconn = mt6370_tcpc_set_vconn;
+
+ priv->vbus = devm_regulator_get_optional(dev, "vbus");
+ if (!IS_ERR(priv->vbus))
+ priv->tcpci_data.set_vbus = mt6370_tcpc_set_vbus;
+
+ priv->tcpci = tcpci_register_port(dev, &priv->tcpci_data);
+ if (IS_ERR(priv->tcpci))
+ return dev_err_probe(dev, PTR_ERR(priv->tcpci),
+ "Failed to register tcpci port\n");
+
+ ret = devm_request_threaded_irq(dev, priv->irq, NULL,
+ mt6370_irq_handler, IRQF_ONESHOT,
+ dev_name(dev), priv);
+ if (ret) {
+ tcpci_unregister_port(priv->tcpci);
+ return dev_err_probe(dev, ret, "Failed to allocate irq\n");
+ }
+
+ device_init_wakeup(dev, true);
+ dev_pm_set_wake_irq(dev, priv->irq);
+
+ return 0;
+}
+
+static int mt6370_tcpc_remove(struct platform_device *pdev)
+{
+ struct mt6370_priv *priv = platform_get_drvdata(pdev);
+
+ disable_irq(priv->irq);
+ tcpci_unregister_port(priv->tcpci);
+ dev_pm_clear_wake_irq(&pdev->dev);
+ device_init_wakeup(&pdev->dev, false);
+
+ return 0;
+}
+
+static const struct of_device_id mt6370_tcpc_devid_table[] = {
+ { .compatible = "mediatek,mt6370-tcpc" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, mt6370_tcpc_devid_table);
+
+static struct platform_driver mt6370_tcpc_driver = {
+ .driver = {
+ .name = "mt6370-tcpc",
+ .of_match_table = mt6370_tcpc_devid_table,
+ },
+ .probe = mt6370_tcpc_probe,
+ .remove = mt6370_tcpc_remove,
+};
+module_platform_driver(mt6370_tcpc_driver);
+
+MODULE_AUTHOR("ChiYuan Huang <[email protected]>");
+MODULE_DESCRIPTION("MT6370 USB Type-C Port Controller Interface Driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4
Il 15/07/22 13:26, ChiaEn Wu ha scritto:
> From: ChiYuan Huang <[email protected]>
>
> The MT6370 is a highly-integrated smart power management IC, which
> includes a single cell Li-Ion/Li-Polymer switching battery charger,
> a USB Type-C & Power Delivery (PD) controller, dual Flash LED current
> sources, a RGB LED driver, a backlight WLED driver, a display bias
> driver and a general LDO for portable devices.
>
> This commit add support for the Type-C & Power Delivery controller in
> MediaTek MT6370 IC.
>
> Signed-off-by: ChiYuan Huang <[email protected]>
Reviewed-by: AngeloGioacchino Del Regno <[email protected]>
On Fri, Jul 15, 2022 at 1:28 PM ChiaEn Wu <[email protected]> wrote:
> The MT6370 is a highly-integrated smart power management IC, which
> includes a single cell Li-Ion/Li-Polymer switching battery charger,
> a USB Type-C & Power Delivery (PD) controller, dual Flash LED current
> sources, a RGB LED driver, a backlight WLED driver, a display bias
> driver and a general LDO for portable devices.
>
> This commit add support for the Type-C & Power Delivery controller in
This commit add -> Add
> MediaTek MT6370 IC.
> +static int mt6370_tcpc_probe(struct platform_device *pdev)
> +{
> + struct mt6370_priv *priv;
> + struct device *dev = &pdev->dev;
> + int ret;
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->dev = dev;
> + platform_set_drvdata(pdev, priv);
> +
> + priv->tcpci_data.regmap = dev_get_regmap(dev->parent, NULL);
> + if (!priv->tcpci_data.regmap)
> + return dev_err_probe(dev, -ENODEV, "Failed to init regmap\n");
> +
> + ret = mt6370_check_vendor_info(priv);
> + if (ret)
> + return ret;
> +
> + priv->irq = platform_get_irq(pdev, 0);
> + if (priv->irq < 0)
> + return priv->irq;
> +
> + /* Assign TCPCI feature and ops */
> + priv->tcpci_data.auto_discharge_disconnect = 1;
> + priv->tcpci_data.init = mt6370_tcpc_init;
> + priv->tcpci_data.set_vconn = mt6370_tcpc_set_vconn;
> +
> + priv->vbus = devm_regulator_get_optional(dev, "vbus");
> + if (!IS_ERR(priv->vbus))
> + priv->tcpci_data.set_vbus = mt6370_tcpc_set_vbus;
> +
> + priv->tcpci = tcpci_register_port(dev, &priv->tcpci_data);
> + if (IS_ERR(priv->tcpci))
> + return dev_err_probe(dev, PTR_ERR(priv->tcpci),
> + "Failed to register tcpci port\n");
> +
> + ret = devm_request_threaded_irq(dev, priv->irq, NULL,
> + mt6370_irq_handler, IRQF_ONESHOT,
> + dev_name(dev), priv);
> + if (ret) {
> + tcpci_unregister_port(priv->tcpci);
This is wrong.
You mixed devm_ with non-devm. Either drop devm_ *after* the first
non-devm_ call, or convert everything to be managed.
> + return dev_err_probe(dev, ret, "Failed to allocate irq\n");
> + }
> +
> + device_init_wakeup(dev, true);
> + dev_pm_set_wake_irq(dev, priv->irq);
> +
> + return 0;
> +}
> +
> +static int mt6370_tcpc_remove(struct platform_device *pdev)
> +{
> + struct mt6370_priv *priv = platform_get_drvdata(pdev);
> + disable_irq(priv->irq);
Why?
An ugly workaround due to ordering issues in ->probe()?
> + tcpci_unregister_port(priv->tcpci);
> + dev_pm_clear_wake_irq(&pdev->dev);
> + device_init_wakeup(&pdev->dev, false);
> +
> + return 0;
> +}
--
With Best Regards,
Andy Shevchenko
On Fri, Jul 15, 2022 at 03:10:42PM +0200, Andy Shevchenko wrote:
> On Fri, Jul 15, 2022 at 1:28 PM ChiaEn Wu <[email protected]> wrote:
>
> > The MT6370 is a highly-integrated smart power management IC, which
> > includes a single cell Li-Ion/Li-Polymer switching battery charger,
> > a USB Type-C & Power Delivery (PD) controller, dual Flash LED current
> > sources, a RGB LED driver, a backlight WLED driver, a display bias
> > driver and a general LDO for portable devices.
> >
> > This commit add support for the Type-C & Power Delivery controller in
>
> This commit add -> Add
>
Upper case? Or rewrite it as 'This commit is to add .....'?
>
> > MediaTek MT6370 IC.
>
>
> > +static int mt6370_tcpc_probe(struct platform_device *pdev)
> > +{
> > + struct mt6370_priv *priv;
> > + struct device *dev = &pdev->dev;
> > + int ret;
> > +
> > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> > + if (!priv)
> > + return -ENOMEM;
> > +
> > + priv->dev = dev;
> > + platform_set_drvdata(pdev, priv);
> > +
> > + priv->tcpci_data.regmap = dev_get_regmap(dev->parent, NULL);
> > + if (!priv->tcpci_data.regmap)
> > + return dev_err_probe(dev, -ENODEV, "Failed to init regmap\n");
> > +
> > + ret = mt6370_check_vendor_info(priv);
> > + if (ret)
> > + return ret;
> > +
> > + priv->irq = platform_get_irq(pdev, 0);
> > + if (priv->irq < 0)
> > + return priv->irq;
> > +
> > + /* Assign TCPCI feature and ops */
> > + priv->tcpci_data.auto_discharge_disconnect = 1;
> > + priv->tcpci_data.init = mt6370_tcpc_init;
> > + priv->tcpci_data.set_vconn = mt6370_tcpc_set_vconn;
> > +
> > + priv->vbus = devm_regulator_get_optional(dev, "vbus");
> > + if (!IS_ERR(priv->vbus))
> > + priv->tcpci_data.set_vbus = mt6370_tcpc_set_vbus;
> > +
> > + priv->tcpci = tcpci_register_port(dev, &priv->tcpci_data);
> > + if (IS_ERR(priv->tcpci))
> > + return dev_err_probe(dev, PTR_ERR(priv->tcpci),
> > + "Failed to register tcpci port\n");
> > +
> > + ret = devm_request_threaded_irq(dev, priv->irq, NULL,
> > + mt6370_irq_handler, IRQF_ONESHOT,
> > + dev_name(dev), priv);
> > + if (ret) {
>
> > + tcpci_unregister_port(priv->tcpci);
>
> This is wrong.
> You mixed devm_ with non-devm. Either drop devm_ *after* the first
> non-devm_ call, or convert everything to be managed.
>
How about to add 'devm_add_action_or_reset' for tcpci_unregister_port?
This will convert all as 'devm_' version.
> > + return dev_err_probe(dev, ret, "Failed to allocate irq\n");
> > + }
> > +
> > + device_init_wakeup(dev, true);
> > + dev_pm_set_wake_irq(dev, priv->irq);
> > +
> > + return 0;
> > +}
> > +
> > +static int mt6370_tcpc_remove(struct platform_device *pdev)
> > +{
> > + struct mt6370_priv *priv = platform_get_drvdata(pdev);
>
> > + disable_irq(priv->irq);
>
> Why?
> An ugly workaround due to ordering issues in ->probe()?
>
Yes, due to the ordering in probe.
'bus remove' will be called before device resource releases.
Like as you said, another way is to convert all as non-devm
version after 'tcpci_unregister_port'.
If to keep the original order, 'disable_irq' before
'tcpci_unregister_port' can make the flow more safe.
Or you can think one case if irq triggers after
'tcpci_unregister_port'. Null pointer occurs.
Anyway, in next revision, I'll convert all to be 'devm_' version.
For this remove callback, only 'dev_pm_clear_wake_irq' and
'device_init_wakeup' will be kept.
Is this better?
> > + tcpci_unregister_port(priv->tcpci);
> > + dev_pm_clear_wake_irq(&pdev->dev);
> > + device_init_wakeup(&pdev->dev, false);
> > +
> > + return 0;
> > +}
>
> --
> With Best Regards,
> Andy Shevchenko
On Mon, Jul 18, 2022 at 10:08 AM ChiYuan Huang <[email protected]> wrote:
> On Fri, Jul 15, 2022 at 03:10:42PM +0200, Andy Shevchenko wrote:
> > On Fri, Jul 15, 2022 at 1:28 PM ChiaEn Wu <[email protected]> wrote:
...
> > > This commit add support for the Type-C & Power Delivery controller in
> >
> > This commit add -> Add
> >
> Upper case? Or rewrite it as 'This commit is to add .....'?
Please, read this documentation [1] for better understanding. It
should clarify this and perhaps other possible questions.
[1]: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes
> > > MediaTek MT6370 IC.
...
> > > + ret = devm_request_threaded_irq(dev, priv->irq, NULL,
> > > + mt6370_irq_handler, IRQF_ONESHOT,
> > > + dev_name(dev), priv);
> > > + if (ret) {
> >
> > > + tcpci_unregister_port(priv->tcpci);
> >
> > This is wrong.
> > You mixed devm_ with non-devm. Either drop devm_ *after* the first
> > non-devm_ call, or convert everything to be managed.
> >
> How about to add 'devm_add_action_or_reset' for tcpci_unregister_port?
> This will convert all as 'devm_' version.
I think it would work, that wrapper was designed to cover cases like this.
> > > + return dev_err_probe(dev, ret, "Failed to allocate irq\n");
> > > + }
...
> > > +static int mt6370_tcpc_remove(struct platform_device *pdev)
> > > +{
> > > + struct mt6370_priv *priv = platform_get_drvdata(pdev);
> >
> > > + disable_irq(priv->irq);
> >
> > Why?
> > An ugly workaround due to ordering issues in ->probe()?
> >
> Yes, due to the ordering in probe.
> 'bus remove' will be called before device resource releases.
>
> Like as you said, another way is to convert all as non-devm
> version after 'tcpci_unregister_port'.
>
> If to keep the original order, 'disable_irq' before
> 'tcpci_unregister_port' can make the flow more safe.
>
> Or you can think one case if irq triggers after
> 'tcpci_unregister_port'. Null pointer occurs.
>
> Anyway, in next revision, I'll convert all to be 'devm_' version.
> For this remove callback, only 'dev_pm_clear_wake_irq' and
> 'device_init_wakeup' will be kept.
>
> Is this better?
Sounds like a plan!
> > > + tcpci_unregister_port(priv->tcpci);
> > > + dev_pm_clear_wake_irq(&pdev->dev);
> > > + device_init_wakeup(&pdev->dev, false);
> > > +
> > > + return 0;
> > > +}
--
With Best Regards,
Andy Shevchenko
Andy Shevchenko <[email protected]> 於 2022年7月18日 週一 晚上7:39寫道：
>
> On Mon, Jul 18, 2022 at 10:08 AM ChiYuan Huang <[email protected]> wrote:
> > On Fri, Jul 15, 2022 at 03:10:42PM +0200, Andy Shevchenko wrote:
> > > On Fri, Jul 15, 2022 at 1:28 PM ChiaEn Wu <[email protected]> wrote:
>
> ...
>
> > > > This commit add support for the Type-C & Power Delivery controller in
> > >
> > > This commit add -> Add
> > >
> > Upper case? Or rewrite it as 'This commit is to add .....'?
>
> Please, read this documentation [1] for better understanding. It
> should clarify this and perhaps other possible questions.
>
> [1]: https://www.kernel.org/doc/html/latest/process/submitting-patches.html#describe-your-changes
>
I'm thinking why to change it from 'add' to "Add'.
Ah, I misunderstand it.
> > > > MediaTek MT6370 IC.
>
> ...
>
> > > > + ret = devm_request_threaded_irq(dev, priv->irq, NULL,
> > > > + mt6370_irq_handler, IRQF_ONESHOT,
> > > > + dev_name(dev), priv);
> > > > + if (ret) {
> > >
> > > > + tcpci_unregister_port(priv->tcpci);
> > >
> > > This is wrong.
> > > You mixed devm_ with non-devm. Either drop devm_ *after* the first
> > > non-devm_ call, or convert everything to be managed.
> > >
> > How about to add 'devm_add_action_or_reset' for tcpci_unregister_port?
> > This will convert all as 'devm_' version.
>
> I think it would work, that wrapper was designed to cover cases like this.
>
> > > > + return dev_err_probe(dev, ret, "Failed to allocate irq\n");
> > > > + }
>
> ...
>
> > > > +static int mt6370_tcpc_remove(struct platform_device *pdev)
> > > > +{
> > > > + struct mt6370_priv *priv = platform_get_drvdata(pdev);
> > >
> > > > + disable_irq(priv->irq);
> > >
> > > Why?
> > > An ugly workaround due to ordering issues in ->probe()?
> > >
> > Yes, due to the ordering in probe.
> > 'bus remove' will be called before device resource releases.
> >
> > Like as you said, another way is to convert all as non-devm
> > version after 'tcpci_unregister_port'.
> >
> > If to keep the original order, 'disable_irq' before
> > 'tcpci_unregister_port' can make the flow more safe.
> >
> > Or you can think one case if irq triggers after
> > 'tcpci_unregister_port'. Null pointer occurs.
> >
> > Anyway, in next revision, I'll convert all to be 'devm_' version.
> > For this remove callback, only 'dev_pm_clear_wake_irq' and
> > 'device_init_wakeup' will be kept.
> >
> > Is this better?
>
> Sounds like a plan!
>
Already did. Just to double confirm the changes.
Thanks. All are clear.
> > > > + tcpci_unregister_port(priv->tcpci);
> > > > + dev_pm_clear_wake_irq(&pdev->dev);
> > > > + device_init_wakeup(&pdev->dev, false);
> > > > +
> > > > + return 0;
> > > > +}
>
> --
> With Best Regards,
> Andy Shevchenko