[PATCH v2 2/4] usb: typec: mux: gpio-sbu-mux: add support for ss data lane muxing

From: Marco Felsch
Date: Thu May 04 2023 - 09:47:53 EST


The commit adds the support to handle gpio based usb-c ss data lanes
muxes as well. The only difference is the data lanes enable handling.
The data lanes don't depend on the alt-mode settings instead they depend
on the usb-c cable orientation (connected, not connected).

Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
---
drivers/usb/typec/mux/Kconfig | 5 +++--
drivers/usb/typec/mux/gpio-sbu-mux.c | 18 +++++++++++++++++-
2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/typec/mux/Kconfig b/drivers/usb/typec/mux/Kconfig
index c46fa4f9d3df..68438e7722d0 100644
--- a/drivers/usb/typec/mux/Kconfig
+++ b/drivers/usb/typec/mux/Kconfig
@@ -13,10 +13,11 @@ config TYPEC_MUX_FSA4480
If compiled as a module, the module will be named fsa4480.

config TYPEC_MUX_GPIO_SBU
- tristate "Generic GPIO based SBU mux for USB Type-C applications"
+ tristate "Generic GPIO based SS/SBU mux for USB Type-C applications"
help
Say Y or M if your system uses a GPIO based mux for managing the
- connected state and the swapping of the SBU lines in a Type-C port.
+ connected state and the swapping of the SS or SBU lines in a Type-C
+ port.

config TYPEC_MUX_PI3USB30532
tristate "Pericom PI3USB30532 Type-C cross switch driver"
diff --git a/drivers/usb/typec/mux/gpio-sbu-mux.c b/drivers/usb/typec/mux/gpio-sbu-mux.c
index f62516dafe8f..a1a560a085b8 100644
--- a/drivers/usb/typec/mux/gpio-sbu-mux.c
+++ b/drivers/usb/typec/mux/gpio-sbu-mux.c
@@ -14,12 +14,18 @@
#include <linux/usb/typec_dp.h>
#include <linux/usb/typec_mux.h>

+enum gpio_sbu_mux_type {
+ MUX_TYPE_SBU,
+ MUX_TYPE_SS,
+};
+
struct gpio_sbu_mux {
struct gpio_desc *enable_gpio;
struct gpio_desc *select_gpio;

struct typec_switch_dev *sw;
struct typec_mux_dev *mux;
+ enum gpio_sbu_mux_type type;

struct mutex lock; /* protect enabled and swapped */
bool enabled;
@@ -38,6 +44,13 @@ static int gpio_sbu_switch_set(struct typec_switch_dev *sw,
enabled = sbu_mux->enabled;
swapped = sbu_mux->swapped;

+ /*
+ * In case of muxing the SS data lanes the enable status depends only on
+ * the orientation and not on the TYPEC_DP_STATE_*
+ */
+ if (sbu_mux->type == MUX_TYPE_SS)
+ enabled = true;
+
switch (orientation) {
case TYPEC_ORIENTATION_NONE:
enabled = false;
@@ -103,6 +116,8 @@ static int gpio_sbu_mux_probe(struct platform_device *pdev)
if (!sbu_mux)
return -ENOMEM;

+ sbu_mux->type = (enum gpio_sbu_mux_type)device_get_match_data(&pdev->dev);
+
mutex_init(&sbu_mux->lock);

sbu_mux->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
@@ -153,7 +168,8 @@ static int gpio_sbu_mux_remove(struct platform_device *pdev)
}

static const struct of_device_id gpio_sbu_mux_match[] = {
- { .compatible = "gpio-sbu-mux", },
+ { .compatible = "gpio-sbu-mux", .data = (void *)MUX_TYPE_SBU },
+ { .compatible = "gpio-ss-mux", .data = (void *)MUX_TYPE_SS },
{}
};
MODULE_DEVICE_TABLE(of, gpio_sbu_mux_match);

--
2.39.2