From 382099d6bcffa13ea729ad5c8f0ae67fafbe563f Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Wed, 30 Aug 2017 11:48:09 +0200 Subject: [PATCH] staging: typec: fusb302: Add support for USB2 charger detection through extcon The fusb302 port-controller relies on an external device doing USB2 charger-type detection. The Intel Whiskey Cove PMIC with which the fusb302 is combined on some X86/ACPI platforms already has a charger-type detection driver which uses extcon to communicate the detected charger-type. Rather then inventing a new API for USB2 charger-type detection specifically for use with the tcpm code, this commit simply re-uses the existing extcon API and uses that do USB2 charger detection. Note that the "fcs,extcon-name" property name is only for kernel internal use by X86/ACPI platform code and as such is NOT documented in the fusb302 devicetree bindings. Cc: "Yueyao (Nathan) Zhu" Signed-off-by: Hans de Goede Reviewed-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- drivers/staging/typec/fusb302/fusb302.c | 49 +++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/drivers/staging/typec/fusb302/fusb302.c b/drivers/staging/typec/fusb302/fusb302.c index 675161cf4f3a..6f007f66d597 100644 --- a/drivers/staging/typec/fusb302/fusb302.c +++ b/drivers/staging/typec/fusb302/fusb302.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -96,6 +97,7 @@ struct fusb302_chip { int gpio_int_n; int gpio_int_n_irq; + struct extcon_dev *extcon; struct workqueue_struct *wq; struct delayed_work bc_lvl_handler; @@ -516,6 +518,38 @@ static int tcpm_get_vbus(struct tcpc_dev *dev) return ret; } +static int tcpm_get_current_limit(struct tcpc_dev *dev) +{ + struct fusb302_chip *chip = container_of(dev, struct fusb302_chip, + tcpc_dev); + int current_limit = 0; + unsigned long timeout; + + if (!chip->extcon) + return 0; + + /* + * USB2 Charger detection may still be in progress when we get here, + * this can take upto 600ms, wait 800ms max. + */ + timeout = jiffies + msecs_to_jiffies(800); + do { + if (extcon_get_state(chip->extcon, EXTCON_CHG_USB_SDP) == 1) + current_limit = 500; + + if (extcon_get_state(chip->extcon, EXTCON_CHG_USB_CDP) == 1 || + extcon_get_state(chip->extcon, EXTCON_CHG_USB_ACA) == 1) + current_limit = 1500; + + if (extcon_get_state(chip->extcon, EXTCON_CHG_USB_DCP) == 1) + current_limit = 2000; + + msleep(50); + } while (current_limit == 0 && time_before(jiffies, timeout)); + + return current_limit; +} + static int fusb302_set_cc_pull(struct fusb302_chip *chip, bool pull_up, bool pull_down) { @@ -1201,6 +1235,7 @@ static void init_tcpc_dev(struct tcpc_dev *fusb302_tcpc_dev) { fusb302_tcpc_dev->init = tcpm_init; fusb302_tcpc_dev->get_vbus = tcpm_get_vbus; + fusb302_tcpc_dev->get_current_limit = tcpm_get_current_limit; fusb302_tcpc_dev->set_cc = tcpm_set_cc; fusb302_tcpc_dev->get_cc = tcpm_get_cc; fusb302_tcpc_dev->set_polarity = tcpm_set_polarity; @@ -1685,6 +1720,7 @@ static int fusb302_probe(struct i2c_client *client, struct fusb302_chip *chip; struct i2c_adapter *adapter; struct device *dev = &client->dev; + const char *name; int ret = 0; u32 v; @@ -1717,6 +1753,19 @@ static int fusb302_probe(struct i2c_client *client, if (!device_property_read_u32(dev, "fcs,operating-sink-microwatt", &v)) chip->tcpc_config.operating_snk_mw = v / 1000; + /* + * Devicetree platforms should get extcon via phandle (not yet + * supported). On ACPI platforms, we get the name from a device prop. + * This device prop is for kernel internal use only and is expected + * to be set by the platform code which also registers the i2c client + * for the fusb302. + */ + if (device_property_read_string(dev, "fcs,extcon-name", &name) == 0) { + chip->extcon = extcon_get_extcon_dev(name); + if (!chip->extcon) + return -EPROBE_DEFER; + } + ret = fusb302_debugfs_init(chip); if (ret < 0) return ret; -- 2.20.1