On 8/28/20 7:33 AM, ChiYuan Huang wrote:

Chunfeng Yun [off-list ref] 於 2020年8月28日 週五 下午8:11寫道：

quoted

On Thu, 2020-08-27 at 19:18 +0800, cy_huang wrote:

quoted

From: ChiYuan Huang <redacted>

Mediatek MT6360 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.

v1 to v2
1. Add fix to Prevent the race condition from interrupt and tcpci port
unregister during module remove.

v2 to v3
1. Change comment style for the head of source code.
2. No need to print error for platform_get_irq_byname.
3. Fix tcpci_register_port check from IS_ERR_OR_NULL to IS_ERR.
4. Rename driver/Kconfig/Makefile form mt6360 to mt636x.
5. Rename DT binding documents from mt6360 to mt636x.

Signed-off-by: ChiYuan Huang <redacted>
---
 drivers/usb/typec/tcpm/Kconfig        |   8 ++
 drivers/usb/typec/tcpm/Makefile       |   1 +
 drivers/usb/typec/tcpm/tcpci_mt6360.c | 212 ++++++++++++++++++++++++++++++++++
 3 files changed, 221 insertions(+)
 create mode 100644 drivers/usb/typec/tcpm/tcpci_mt6360.c

diff --git a/drivers/usb/typec/tcpm/Kconfig b/drivers/usb/typec/tcpm/Kconfig
index fa3f393..58a64e1 100644
--- a/drivers/usb/typec/tcpm/Kconfig
+++ b/drivers/usb/typec/tcpm/Kconfig

@@ -27,6 +27,14 @@ config TYPEC_RT1711H
        Type-C Port Controller Manager to provide USB PD and USB
        Type-C functionalities.

+config TYPEC_MT6360
+     tristate "Mediatek MT6360 Type-C driver"
+     depends on MFD_MT6360
+     help
+       Mediatek MT6360 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.
+
 endif # TYPEC_TCPCI

 config TYPEC_FUSB302

diff --git a/drivers/usb/typec/tcpm/Makefile b/drivers/usb/typec/tcpm/Makefile
index a5ff6c8..7592ccb 100644
--- a/drivers/usb/typec/tcpm/Makefile
+++ b/drivers/usb/typec/tcpm/Makefile

@@ -5,3 +5,4 @@ obj-$(CONFIG_TYPEC_WCOVE)     += typec_wcove.o
 typec_wcove-y                        := wcove.o
 obj-$(CONFIG_TYPEC_TCPCI)    += tcpci.o
 obj-$(CONFIG_TYPEC_RT1711H)  += tcpci_rt1711h.o
+obj-$(CONFIG_TYPEC_MT6360)   += tcpci_mt6360.o

diff --git a/drivers/usb/typec/tcpm/tcpci_mt6360.c b/drivers/usb/typec/tcpm/tcpci_mt6360.c
new file mode 100644
index 00000000..f1bd9e0
--- /dev/null
+++ b/drivers/usb/typec/tcpm/tcpci_mt6360.c

@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 MediaTek Inc.
+ *
+ * Author: ChiYuan Huang <cy_huang@richtek.com>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/usb/tcpm.h>
+
+#include "tcpci.h"
+
+#define MT6360_REG_VCONNCTRL1        0x8C
+#define MT6360_REG_MODECTRL2 0x8F
+#define MT6360_REG_SWRESET   0xA0
+#define MT6360_REG_DEBCTRL1  0xA1
+#define MT6360_REG_DRPCTRL1  0xA2
+#define MT6360_REG_DRPCTRL2  0xA3
+#define MT6360_REG_I2CTORST  0xBF
+#define MT6360_REG_RXCTRL2   0xCF
+#define MT6360_REG_CTDCTRL2  0xEC
+
+/* MT6360_REG_VCONNCTRL1 */
+#define MT6360_VCONNCL_ENABLE        BIT(0)
+/* MT6360_REG_RXCTRL2 */
+#define MT6360_OPEN40M_ENABLE        BIT(7)
+/* MT6360_REG_CTDCTRL2 */
+#define MT6360_RPONESHOT_ENABLE      BIT(6)
+
+struct mt6360_tcpc_info {
+     struct tcpci_data tdata;
+     struct tcpci *tcpci;
+     struct device *dev;
+     int irq;
+};
+
+static inline int mt6360_tcpc_read16(struct regmap *regmap,
+                                  unsigned int reg, u16 *val)
+{
+     return regmap_raw_read(regmap, reg, val, sizeof(u16));
+}
+
+static inline int mt6360_tcpc_write16(struct regmap *regmap,
+                                   unsigned int reg, u16 val)
+{
+     return regmap_raw_write(regmap, reg, &val, sizeof(u16));
+}
+
+static int mt6360_tcpc_init(struct tcpci *tcpci, struct tcpci_data *tdata)
+{
+     struct regmap *regmap = tdata->regmap;
+     int ret;
+
+     ret = regmap_write(regmap, MT6360_REG_SWRESET, 0x01);
+     if (ret)
+             return ret;
+
+     /* after reset command, wait 1~2ms to wait IC action */
+     usleep_range(1000, 2000);
+
+     /* write all alert to masked */
+     ret = mt6360_tcpc_write16(regmap, TCPC_ALERT_MASK, 0);

Wonder why access some register by 2bytes, and others 4bytes?
can we access them all by 4bytes?

Actually, the access bus is still I2C.
Each register is still one byte only.
Register address like as TCPC_ALERT_MASK are continuous two byte used
as IRQ MASK.
That's why it's used wirte16 function to access.

Actually, you also can divided into two bytes write into one byte
access by two times.
For I2C bus efficiency, it seems bad.

For MT6360_REG_DRPCTRL2, it might also be racy, since the two i2c addresses
are really one register containing a 10-bit value. I would probably not matter
here (afaics the value is changed from the default 327 to 330), but in general
it seems safer to write such a value with a single 16-bit i2c write.

Guenter