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authorThinh Nguyen2021-01-19 17:36:14 -0800
committerGreg Kroah-Hartman2021-02-06 14:21:21 +0100
commit52c2d15703c3a900d5f78cd599b823db40d5100b (patch)
treec5dceb701423f894c87246d49aafba1ec5c1fce5
parentde4d9ea789530ac0ce3409878422e9389c3a7cd3 (diff)
usb: common: Parse for USB SSP genXxY
The USB "maximum-speed" property can now take the SSP signaling rate generation and lane count with these new strings: "super-speed-plus-gen2x2" "super-speed-plus-gen2x1" "super-speed-plus-gen1x2" Introduce usb_get_maximum_ssp_rate() to parse for the corresponding usb_ssp_rate enum. The original usb_get_maximum_speed() will return USB_SPEED_SUPER_PLUS if it matches one of these new strings. Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com> Link: https://lore.kernel.org/r/f8ed896313d8cd8e2d2b540fc82db92b3ddf8a47.1611106162.git.Thinh.Nguyen@synopsys.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/common/common.c26
-rw-r--r--include/linux/usb/ch9.h11
2 files changed, 36 insertions, 1 deletions
diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
index 1433260d99b4..fc21cf2d36f6 100644
--- a/drivers/usb/common/common.c
+++ b/drivers/usb/common/common.c
@@ -69,6 +69,13 @@ static const char *const speed_names[] = {
[USB_SPEED_SUPER_PLUS] = "super-speed-plus",
};
+static const char *const ssp_rate[] = {
+ [USB_SSP_GEN_UNKNOWN] = "UNKNOWN",
+ [USB_SSP_GEN_2x1] = "super-speed-plus-gen2x1",
+ [USB_SSP_GEN_1x2] = "super-speed-plus-gen1x2",
+ [USB_SSP_GEN_2x2] = "super-speed-plus-gen2x2",
+};
+
const char *usb_speed_string(enum usb_device_speed speed)
{
if (speed < 0 || speed >= ARRAY_SIZE(speed_names))
@@ -86,12 +93,29 @@ enum usb_device_speed usb_get_maximum_speed(struct device *dev)
if (ret < 0)
return USB_SPEED_UNKNOWN;
- ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
+ ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
+ if (ret > 0)
+ return USB_SPEED_SUPER_PLUS;
+ ret = match_string(speed_names, ARRAY_SIZE(speed_names), maximum_speed);
return (ret < 0) ? USB_SPEED_UNKNOWN : ret;
}
EXPORT_SYMBOL_GPL(usb_get_maximum_speed);
+enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev)
+{
+ const char *maximum_speed;
+ int ret;
+
+ ret = device_property_read_string(dev, "maximum-speed", &maximum_speed);
+ if (ret < 0)
+ return USB_SSP_GEN_UNKNOWN;
+
+ ret = match_string(ssp_rate, ARRAY_SIZE(ssp_rate), maximum_speed);
+ return (ret < 0) ? USB_SSP_GEN_UNKNOWN : ret;
+}
+EXPORT_SYMBOL_GPL(usb_get_maximum_ssp_rate);
+
const char *usb_state_string(enum usb_device_state state)
{
static const char *const names[] = {
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h
index 86c50907634e..abdd310c77f0 100644
--- a/include/linux/usb/ch9.h
+++ b/include/linux/usb/ch9.h
@@ -72,6 +72,17 @@ extern const char *usb_speed_string(enum usb_device_speed speed);
extern enum usb_device_speed usb_get_maximum_speed(struct device *dev);
/**
+ * usb_get_maximum_ssp_rate - Get the signaling rate generation and lane count
+ * of a SuperSpeed Plus capable device.
+ * @dev: Pointer to the given USB controller device
+ *
+ * If the string from "maximum-speed" property is super-speed-plus-genXxY where
+ * 'X' is the generation number and 'Y' is the number of lanes, then this
+ * function returns the corresponding enum usb_ssp_rate.
+ */
+extern enum usb_ssp_rate usb_get_maximum_ssp_rate(struct device *dev);
+
+/**
* usb_state_string - Returns human readable name for the state.
* @state: The state to return a human-readable name for. If it's not
* any of the states devices in usb_device_state_string enum,