[PATCH v4 17/20] extcon: intel-cht-wc: Support devs with Micro-B / USB-2 only Type-C connectors

Hans de Goede
2021-12-06T09:36:15Z

So far the extcon-intel-cht-wc code has only been tested on devices with
a Type-C connector with USB-PD, USB3 (superspeed) and DP-altmode support
through a FUSB302 Type-C controller.

Some devices with the intel-cht-wc PMIC however come with an USB-micro-B
connector, or an USB-2 only Type-C connector without USB-PD.

Which device-model we are running on can be identified with the new
cht_wc_model intel_soc_pmic field. On models without a Type-C controller
the extcon code must control the Vbus 5V boost converter and the USB role
switch depending on the detected cable-type.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
Changes in v3:
- Some minor tweaks / spelling fixes based on Andy's review
---
drivers/extcon/Kconfig | 2 +
drivers/extcon/extcon-intel-cht-wc.c | 91 ++++++++++++++++++++++++++++
2 files changed, 93 insertions(+)

diff --git a/drivers/extcon/Kconfig b/drivers/extcon/Kconfig
index aab87c9b35c8..0d42e49105dd 100644
--- a/drivers/extcon/Kconfig
+++ b/drivers/extcon/Kconfig
@@ -61,6 +61,8 @@ config EXTCON_INTEL_INT3496
config EXTCON_INTEL_CHT_WC
tristate "Intel Cherrytrail Whiskey Cove PMIC extcon driver"
depends on INTEL_SOC_PMIC_CHTWC
+ depends on USB_SUPPORT
+ select USB_ROLE_SWITCH
help
Say Y here to enable extcon support for charger detection / control
on the Intel Cherrytrail Whiskey Cove PMIC.
diff --git a/drivers/extcon/extcon-intel-cht-wc.c b/drivers/extcon/extcon-intel-cht-wc.c
index 81cae8c75850..edc386937dee 100644
--- a/drivers/extcon/extcon-intel-cht-wc.c
+++ b/drivers/extcon/extcon-intel-cht-wc.c
@@ -16,7 +16,9 @@
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
#include <linux/slab.h>
+#include <linux/usb/role.h>

#include "extcon-intel.h"

@@ -102,8 +104,11 @@ struct cht_wc_extcon_data {
struct device *dev;
struct regmap *regmap;
struct extcon_dev *edev;
+ struct usb_role_switch *role_sw;
+ struct regulator *vbus_boost;
unsigned int previous_cable;
bool usb_host;
+ bool vbus_boost_enabled;
};

static int cht_wc_extcon_get_id(struct cht_wc_extcon_data *ext, int pwrsrc_sts)
@@ -217,6 +222,18 @@ static void cht_wc_extcon_set_otgmode(struct cht_wc_extcon_data *ext,
CHT_WC_CHGRCTRL1_OTGMODE, val);
if (ret)
dev_err(ext->dev, "Error updating CHGRCTRL1 reg: %d\n", ret);
+
+ if (ext->vbus_boost && ext->vbus_boost_enabled != enable) {
+ if (enable)
+ ret = regulator_enable(ext->vbus_boost);
+ else
+ ret = regulator_disable(ext->vbus_boost);
+
+ if (ret == 0)
+ ext->vbus_boost_enabled = enable;
+ else
+ dev_err(ext->dev, "Error updating Vbus boost regulator: %d\n", ret);
+ }
}

static void cht_wc_extcon_enable_charging(struct cht_wc_extcon_data *ext,
@@ -246,6 +263,7 @@ static void cht_wc_extcon_pwrsrc_event(struct cht_wc_extcon_data *ext)
unsigned int cable = EXTCON_NONE;
/* Ignore errors in host mode, as the 5v boost converter is on then */
bool ignore_get_charger_errors = ext->usb_host;
+ enum usb_role role;

ret = regmap_read(ext->regmap, CHT_WC_PWRSRC_STS, &pwrsrc_sts);
if (ret) {
@@ -289,6 +307,18 @@ static void cht_wc_extcon_pwrsrc_event(struct cht_wc_extcon_data *ext)

ext->usb_host = ((id == INTEL_USB_ID_GND) || (id == INTEL_USB_RID_A));
extcon_set_state_sync(ext->edev, EXTCON_USB_HOST, ext->usb_host);
+
+ if (ext->usb_host)
+ role = USB_ROLE_HOST;
+ else if (pwrsrc_sts & CHT_WC_PWRSRC_VBUS)
+ role = USB_ROLE_DEVICE;
+ else
+ role = USB_ROLE_NONE;
+
+ /* Note: this is a no-op when ext->role_sw is NULL */
+ ret = usb_role_switch_set_role(ext->role_sw, role);
+ if (ret)
+ dev_err(ext->dev, "Error setting USB-role: %d\n", ret);
}

static irqreturn_t cht_wc_extcon_isr(int irq, void *data)
@@ -334,6 +364,61 @@ static int cht_wc_extcon_sw_control(struct cht_wc_extcon_data *ext, bool enable)
return ret;
}

+static int cht_wc_extcon_find_role_sw(struct cht_wc_extcon_data *ext)
+{
+ const struct software_node *swnode;
+ struct fwnode_handle *fwnode;
+
+ swnode = software_node_find_by_name(NULL, "intel-xhci-usb-sw");
+ if (!swnode)
+ return -EPROBE_DEFER;
+
+ fwnode = software_node_fwnode(swnode);
+ ext->role_sw = usb_role_switch_find_by_fwnode(fwnode);
+ fwnode_handle_put(fwnode);
+
+ return ext->role_sw ? 0 : -EPROBE_DEFER;
+}
+
+static void cht_wc_extcon_put_role_sw(void *data)
+{
+ struct cht_wc_extcon_data *ext = data;
+
+ usb_role_switch_put(ext->role_sw);
+}
+
+/* Some boards require controlling the role-sw and Vbus based on the id-pin */
+static int cht_wc_extcon_get_role_sw_and_regulator(struct cht_wc_extcon_data *ext)
+{
+ int ret;
+
+ ret = cht_wc_extcon_find_role_sw(ext);
+ if (ret)
+ return ret;
+
+ ret = devm_add_action_or_reset(ext->dev, cht_wc_extcon_put_role_sw, ext);
+ if (ret)
+ return ret;
+
+ /*
+ * On x86/ACPI platforms the regulator <-> consumer link is provided
+ * by platform_data passed to the regulator driver. This means that
+ * this info is not available before the regulator driver has bound.
+ * Use devm_regulator_get_optional() to avoid getting a dummy
+ * regulator and wait for the regulator to show up if necessary.
+ */
+ ext->vbus_boost = devm_regulator_get_optional(ext->dev, "vbus");
+ if (IS_ERR(ext->vbus_boost)) {
+ ret = PTR_ERR(ext->vbus_boost);
+ if (ret == -ENODEV)
+ ret = -EPROBE_DEFER;
+
+ return dev_err_probe(ext->dev, ret, "getting Vbus regulator");
+ }
+
+ return 0;
+}
+
static int cht_wc_extcon_probe(struct platform_device *pdev)
{
struct intel_soc_pmic *pmic = dev_get_drvdata(pdev->dev.parent);
@@ -376,6 +461,12 @@ static int cht_wc_extcon_probe(struct platform_device *pdev)
*/
cht_wc_extcon_set_5v_boost(ext, false);
break;
+ case INTEL_CHT_WC_LENOVO_YOGABOOK1:
+ case INTEL_CHT_WC_XIAOMI_MIPAD2:
+ ret = cht_wc_extcon_get_role_sw_and_regulator(ext);
+ if (ret)
+ return ret;
+ break;
default:
break;
}
--
2.33.1