HI, reviews:

ChiYuan Huang [off-list ref] 於 2021年1月19日 週二 下午4:23寫道：

Chunfeng Yun [off-list ref] 於 2021年1月19日 週二 下午3:38寫道：

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On Mon, 2021-01-18 at 16:28 +0800, ChiYuan Huang wrote:

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Guenter Roeck [off-list ref] 於 2021年1月18日 週一 上午1:43寫道：

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On 1/15/21 6:13 AM, cy_huang wrote:

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From: ChiYuan Huang <redacted>

MT6360 not support for TCPC command to control source and sink.

does not

Ack

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Uses external 5V vbus regulator as the vbus source control.

Use

Ack

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Also adds the capability to report vsafe0v.

add

Ack

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So far this driver works without regulator. Unless I am missing something,
this patch makes regulator support mandatory, meaning existing code will fail.
I am not sure if that is appropriate/acceptable. Can we be sure that this will
work for existing users of this driver ?

Yes, I already checked all the src/snk functionality based on  the
latest typec code.
It'll be common for our TCPC. It didn't support for TCPC command.
From the recent patches, actually, I have the local change to test the
src capability.
But I didn't submit it. It's almost the same to add set_vbus callback.
That's why I submit this change after tcpci 'set_vbus callback' is added.

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Thanks,
Guenter

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Signed-off-by: ChiYuan Huang <redacted>
---
 drivers/usb/typec/tcpm/tcpci_mt6360.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/usb/typec/tcpm/tcpci_mt6360.c b/drivers/usb/typec/tcpm/tcpci_mt6360.c
index f1bd9e0..0edf4b6 100644
--- a/drivers/usb/typec/tcpm/tcpci_mt6360.c
+++ b/drivers/usb/typec/tcpm/tcpci_mt6360.c

@@ -11,6 +11,7 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 #include <linux/usb/tcpm.h>

 #include "tcpci.h"

@@ -36,6 +37,7 @@ struct mt6360_tcpc_info {
      struct tcpci_data tdata;
      struct tcpci *tcpci;
      struct device *dev;
+     struct regulator *vbus;
      int irq;
 };

@@ -51,6 +53,27 @@ static inline int mt6360_tcpc_write16(struct regmap *regmap,
      return regmap_raw_write(regmap, reg, &val, sizeof(u16));
 }

+static int mt6360_tcpc_set_vbus(struct tcpci *tcpci, struct tcpci_data *data, bool src, bool snk)
+{
+     struct mt6360_tcpc_info *mti = container_of(data, struct mt6360_tcpc_info, tdata);
+     int ret;
+
+     /* To correctly handle the already enabled vbus and disable its supply first */
+     if (regulator_is_enabled(mti->vbus)) {
+             ret = regulator_disable(mti->vbus);
+             if (ret)
+                     return ret;
+     }

Is it really a good idea to disable vbus if it happens to be already enabled
and there is (another ?) request to enable it ?

Yes, for  the state change from src_attach_wait to src_attach,
It need to meet the requirement that  the vbus is at vsafe0v.
So to disable it first is needed.
And to prevent other users from enabling/disabling external vbus
regulator in any case.
I think we may change regulator_get  to 'regulator_get_exclusive'.
From the design, 5v regulator only can be controlled via typec framework.
If other user touch it, it'll affect the typec state transition.

How about to process the case that even switch usb controller to device
mode, platform also need to keep vbus on? e.g. Iphone Carplay

It must be processed by USBPD data role swap.

Type C only decide the initial role (SNK: power snk and ufp; SRC:
power src and DFP).
Only USBPD can change the power/data/vconn role individually.

I'm  not sure the status about this patch.
But I'm trying to figure out the problems about some TCPCs.

Not all TCPCs can support the source_vbus/sink_vbus command.
I'm trying to add this patch make our mt6360 tcpc work.

Originally, I add some proprietary code in usb to make the otg vbus
output due to no set_vbus callback handled by vendor ops.

Eventually, I found the patch
b9358a068490 usb: typec: tcpci: Add set_vbus tcpci callback

Hope to get any response from you.

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+
+     if (src) {
+             ret = regulator_enable(mti->vbus);
+             if (ret)
+                     return ret;
+     }
+
+     return 0;
+}
+
 static int mt6360_tcpc_init(struct tcpci *tcpci, struct tcpci_data *tdata)
 {
      struct regmap *regmap = tdata->regmap;

@@ -138,7 +161,13 @@ static int mt6360_tcpc_probe(struct platform_device *pdev)
      if (mti->irq < 0)
              return mti->irq;

+     mti->vbus = devm_regulator_get(&pdev->dev, "vbus");
+     if (IS_ERR(mti->vbus))
+             return PTR_ERR(mti->vbus);
+
      mti->tdata.init = mt6360_tcpc_init;
+     mti->tdata.set_vbus = mt6360_tcpc_set_vbus;
+     mti->tdata.vbus_vsafe0v = 1;
      mti->tcpci = tcpci_register_port(&pdev->dev, &mti->tdata);
      if (IS_ERR(mti->tcpci)) {
              dev_err(&pdev->dev, "Failed to register tcpci port\n");

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