[PATCH v4 6/6] usb: mtu3: register a USB Role Switch for dual role mode

Chunfeng Yun
2019-04-26T06:47:17Z

Because extcon is not allowed for new bindings, and the
dual role switch is supported by USB Role Switch,
especially for Type-C drivers, so register a USB Role
Switch to support the new way

Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
---
v4 changes:
1. assign fwnode member of usb_role_switch struct suggested by Heikki

v3 changes:
1. select USB_ROLE_SWITCH in Kconfig suggested by Heikki
2. rename ssusb_mode_manual_switch() to ssusb_mode_switch()

v2 no change
---
drivers/usb/mtu3/Kconfig | 1 +
drivers/usb/mtu3/mtu3.h | 5 ++++
drivers/usb/mtu3/mtu3_debugfs.c | 4 +--
drivers/usb/mtu3/mtu3_dr.c | 48 ++++++++++++++++++++++++++++++++-
drivers/usb/mtu3/mtu3_dr.h | 6 ++---
drivers/usb/mtu3/mtu3_plat.c | 3 ++-
6 files changed, 60 insertions(+), 7 deletions(-)

diff --git a/drivers/usb/mtu3/Kconfig b/drivers/usb/mtu3/Kconfig
index bcc23486c4ed..88e3db7b3016 100644
--- a/drivers/usb/mtu3/Kconfig
+++ b/drivers/usb/mtu3/Kconfig
@@ -43,6 +43,7 @@ config USB_MTU3_DUAL_ROLE
bool "Dual Role mode"
depends on ((USB=y || USB=USB_MTU3) && (USB_GADGET=y || USB_GADGET=USB_MTU3))
depends on (EXTCON=y || EXTCON=USB_MTU3)
+ select USB_ROLE_SWITCH
help
This is the default mode of working of MTU3 controller where
both host and gadget features are enabled.
diff --git a/drivers/usb/mtu3/mtu3.h b/drivers/usb/mtu3/mtu3.h
index 76ecf12fdf62..6087be236a35 100644
--- a/drivers/usb/mtu3/mtu3.h
+++ b/drivers/usb/mtu3/mtu3.h
@@ -199,6 +199,9 @@ struct mtu3_gpd_ring {
* @id_nb : notifier for iddig(idpin) detection
* @id_work : work of iddig detection notifier
* @id_event : event of iddig detecion notifier
+* @role_sw : use USB Role Switch to support dual-role switch, can't use
+* extcon at the same time, and extcon is deprecated.
+* @role_sw_used : true when the USB Role Switch is used.
* @is_u3_drd: whether port0 supports usb3.0 dual-role device or not
* @manual_drd_enabled: it's true when supports dual-role device by debugfs
* to switch host/device modes depending on user input.
@@ -212,6 +215,8 @@ struct otg_switch_mtk {
struct notifier_block id_nb;
struct work_struct id_work;
unsigned long id_event;
+ struct usb_role_switch *role_sw;
+ bool role_sw_used;
bool is_u3_drd;
bool manual_drd_enabled;
};
diff --git a/drivers/usb/mtu3/mtu3_debugfs.c b/drivers/usb/mtu3/mtu3_debugfs.c
index 62c57ddc554e..c96e5dab0a48 100644
--- a/drivers/usb/mtu3/mtu3_debugfs.c
+++ b/drivers/usb/mtu3/mtu3_debugfs.c
@@ -453,9 +453,9 @@ static ssize_t ssusb_mode_write(struct file *file, const char __user *ubuf,
return -EFAULT;

if (!strncmp(buf, "host", 4) && !ssusb->is_host) {
- ssusb_mode_manual_switch(ssusb, 1);
+ ssusb_mode_switch(ssusb, 1);
} else if (!strncmp(buf, "device", 6) && ssusb->is_host) {
- ssusb_mode_manual_switch(ssusb, 0);
+ ssusb_mode_switch(ssusb, 0);
} else {
dev_err(ssusb->dev, "wrong or duplicated setting\n");
return -EINVAL;
diff --git a/drivers/usb/mtu3/mtu3_dr.c b/drivers/usb/mtu3/mtu3_dr.c
index 5fcb71af875a..08e18448e8b8 100644
--- a/drivers/usb/mtu3/mtu3_dr.c
+++ b/drivers/usb/mtu3/mtu3_dr.c
@@ -7,6 +7,8 @@
* Author: Chunfeng Yun <chunfeng.yun@mediatek.com>
*/

+#include <linux/usb/role.h>
+
#include "mtu3.h"
#include "mtu3_dr.h"
#include "mtu3_debug.h"
@@ -280,7 +282,7 @@ static int ssusb_extcon_register(struct otg_switch_mtk *otg_sx)
* This is useful in special cases, such as uses TYPE-A receptacle but also
* wants to support dual-role mode.
*/
-void ssusb_mode_manual_switch(struct ssusb_mtk *ssusb, int to_host)
+void ssusb_mode_switch(struct ssusb_mtk *ssusb, int to_host)
{
struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;

@@ -318,6 +320,47 @@ void ssusb_set_force_mode(struct ssusb_mtk *ssusb,
mtu3_writel(ssusb->ippc_base, SSUSB_U2_CTRL(0), value);
}

+static int ssusb_role_sw_set(struct device *dev, enum usb_role role)
+{
+ struct ssusb_mtk *ssusb = dev_get_drvdata(dev);
+ bool to_host = false;
+
+ if (role == USB_ROLE_HOST)
+ to_host = true;
+
+ if (to_host ^ ssusb->is_host)
+ ssusb_mode_switch(ssusb, to_host);
+
+ return 0;
+}
+
+static enum usb_role ssusb_role_sw_get(struct device *dev)
+{
+ struct ssusb_mtk *ssusb = dev_get_drvdata(dev);
+ enum usb_role role;
+
+ role = ssusb->is_host ? USB_ROLE_HOST : USB_ROLE_DEVICE;
+
+ return role;
+}
+
+static int ssusb_role_sw_register(struct otg_switch_mtk *otg_sx)
+{
+ struct usb_role_switch_desc role_sx_desc = { 0 };
+ struct ssusb_mtk *ssusb =
+ container_of(otg_sx, struct ssusb_mtk, otg_switch);
+
+ if (!otg_sx->role_sw_used)
+ return 0;
+
+ role_sx_desc.set = ssusb_role_sw_set;
+ role_sx_desc.get = ssusb_role_sw_get;
+ role_sx_desc.fwnode = dev_fwnode(ssusb->dev);
+ otg_sx->role_sw = usb_role_switch_register(ssusb->dev, &role_sx_desc);
+
+ return PTR_ERR_OR_ZERO(otg_sx->role_sw);
+}
+
int ssusb_otg_switch_init(struct ssusb_mtk *ssusb)
{
struct otg_switch_mtk *otg_sx = &ssusb->otg_switch;
@@ -328,6 +371,8 @@ int ssusb_otg_switch_init(struct ssusb_mtk *ssusb)

if (otg_sx->manual_drd_enabled)
ssusb_dr_debugfs_init(ssusb);
+ else if (otg_sx->role_sw_used)
+ ret = ssusb_role_sw_register(otg_sx);
else
ret = ssusb_extcon_register(otg_sx);

@@ -340,4 +385,5 @@ void ssusb_otg_switch_exit(struct ssusb_mtk *ssusb)

cancel_work_sync(&otg_sx->id_work);
cancel_work_sync(&otg_sx->vbus_work);
+ usb_role_switch_unregister(otg_sx->role_sw);
}
diff --git a/drivers/usb/mtu3/mtu3_dr.h b/drivers/usb/mtu3/mtu3_dr.h
index ba6fe357ce29..5e58c4dbd54a 100644
--- a/drivers/usb/mtu3/mtu3_dr.h
+++ b/drivers/usb/mtu3/mtu3_dr.h
@@ -71,7 +71,7 @@ static inline void ssusb_gadget_exit(struct ssusb_mtk *ssusb)
#if IS_ENABLED(CONFIG_USB_MTU3_DUAL_ROLE)
int ssusb_otg_switch_init(struct ssusb_mtk *ssusb);
void ssusb_otg_switch_exit(struct ssusb_mtk *ssusb);
-void ssusb_mode_manual_switch(struct ssusb_mtk *ssusb, int to_host);
+void ssusb_mode_switch(struct ssusb_mtk *ssusb, int to_host);
int ssusb_set_vbus(struct otg_switch_mtk *otg_sx, int is_on);
void ssusb_set_force_mode(struct ssusb_mtk *ssusb,
enum mtu3_dr_force_mode mode);
@@ -86,8 +86,8 @@ static inline int ssusb_otg_switch_init(struct ssusb_mtk *ssusb)
static inline void ssusb_otg_switch_exit(struct ssusb_mtk *ssusb)
{}

-static inline void
-ssusb_mode_manual_switch(struct ssusb_mtk *ssusb, int to_host) {}
+static inline void ssusb_mode_switch(struct ssusb_mtk *ssusb, int to_host)
+{}

static inline int ssusb_set_vbus(struct otg_switch_mtk *otg_sx, int is_on)
{
diff --git a/drivers/usb/mtu3/mtu3_plat.c b/drivers/usb/mtu3/mtu3_plat.c
index fd0f6c5dfbc1..9c256ea3cdf5 100644
--- a/drivers/usb/mtu3/mtu3_plat.c
+++ b/drivers/usb/mtu3/mtu3_plat.c
@@ -299,8 +299,9 @@ static int get_ssusb_rscs(struct platform_device *pdev, struct ssusb_mtk *ssusb)
otg_sx->is_u3_drd = of_property_read_bool(node, "mediatek,usb3-drd");
otg_sx->manual_drd_enabled =
of_property_read_bool(node, "enable-manual-drd");
+ otg_sx->role_sw_used = of_property_read_bool(node, "usb-role-switch");

- if (of_property_read_bool(node, "extcon")) {
+ if (!otg_sx->role_sw_used && of_property_read_bool(node, "extcon")) {
otg_sx->edev = extcon_get_edev_by_phandle(ssusb->dev, 0);
if (IS_ERR(otg_sx->edev)) {
dev_err(ssusb->dev, "couldn't get extcon device\n");
--
2.21.0