diff options
Diffstat (limited to 'drivers/extcon/extcon-axp288.c')
-rw-r--r-- | drivers/extcon/extcon-axp288.c | 176 |
1 files changed, 168 insertions, 8 deletions
diff --git a/drivers/extcon/extcon-axp288.c b/drivers/extcon/extcon-axp288.c index 3ec4c71..a983708 100644 --- a/drivers/extcon/extcon-axp288.c +++ b/drivers/extcon/extcon-axp288.c @@ -1,6 +1,7 @@ /* * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver * + * Copyright (c) 2017-2018 Hans de Goede <hdegoede@redhat.com> * Copyright (C) 2015 Intel Corporation * Author: Ramakrishna Pallala <ramakrishna.pallala@intel.com> * @@ -14,6 +15,7 @@ * GNU General Public License for more details. */ +#include <linux/acpi.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/io.h> @@ -25,6 +27,11 @@ #include <linux/extcon-provider.h> #include <linux/regmap.h> #include <linux/mfd/axp20x.h> +#include <linux/usb/role.h> +#include <linux/workqueue.h> + +#include <asm/cpu_device_id.h> +#include <asm/intel-family.h> /* Power source status register */ #define PS_STAT_VBUS_TRIGGER BIT(0) @@ -97,9 +104,19 @@ struct axp288_extcon_info { struct device *dev; struct regmap *regmap; struct regmap_irq_chip_data *regmap_irqc; + struct usb_role_switch *role_sw; + struct work_struct role_work; int irq[EXTCON_IRQ_END]; struct extcon_dev *edev; + struct extcon_dev *id_extcon; + struct notifier_block id_nb; unsigned int previous_cable; + bool vbus_attach; +}; + +static const struct x86_cpu_id cherry_trail_cpu_ids[] = { + { X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT, X86_FEATURE_ANY }, + {} }; /* Power up/down reason string array */ @@ -137,20 +154,74 @@ static void axp288_extcon_log_rsi(struct axp288_extcon_info *info) regmap_write(info->regmap, AXP288_PS_BOOT_REASON_REG, clear_mask); } -static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info) +/* + * The below code to control the USB role-switch on devices with an AXP288 + * may seem out of place, but there are 2 reasons why this is the best place + * to control the USB role-switch on such devices: + * 1) On many devices the USB role is controlled by AML code, but the AML code + * only switches between the host and none roles, because of Windows not + * really using device mode. To make device mode work we need to toggle + * between the none/device roles based on Vbus presence, and this driver + * gets interrupts on Vbus insertion / removal. + * 2) In order for our BC1.2 charger detection to work properly the role + * mux must be properly set to device mode before we do the detection. + */ + +/* Returns the id-pin value, note pulled low / false == host-mode */ +static bool axp288_get_id_pin(struct axp288_extcon_info *info) { - int ret, stat, cfg, pwr_stat; - u8 chrg_type; - unsigned int cable = info->previous_cable; - bool vbus_attach = false; + enum usb_role role; + + if (info->id_extcon) + return extcon_get_state(info->id_extcon, EXTCON_USB_HOST) <= 0; + + /* We cannot access the id-pin, see what mode the AML code has set */ + role = usb_role_switch_get_role(info->role_sw); + return role != USB_ROLE_HOST; +} + +static void axp288_usb_role_work(struct work_struct *work) +{ + struct axp288_extcon_info *info = + container_of(work, struct axp288_extcon_info, role_work); + enum usb_role role; + bool id_pin; + int ret; + + id_pin = axp288_get_id_pin(info); + if (!id_pin) + role = USB_ROLE_HOST; + else if (info->vbus_attach) + role = USB_ROLE_DEVICE; + else + role = USB_ROLE_NONE; + + ret = usb_role_switch_set_role(info->role_sw, role); + if (ret) + dev_err(info->dev, "failed to set role: %d\n", ret); +} + +static bool axp288_get_vbus_attach(struct axp288_extcon_info *info) +{ + int ret, pwr_stat; ret = regmap_read(info->regmap, AXP288_PS_STAT_REG, &pwr_stat); if (ret < 0) { dev_err(info->dev, "failed to read vbus status\n"); - return ret; + return false; } - vbus_attach = (pwr_stat & PS_STAT_VBUS_VALID); + return !!(pwr_stat & PS_STAT_VBUS_VALID); +} + +static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info) +{ + int ret, stat, cfg; + u8 chrg_type; + unsigned int cable = info->previous_cable; + bool vbus_attach = false; + + vbus_attach = axp288_get_vbus_attach(info); if (!vbus_attach) goto no_vbus; @@ -201,6 +272,12 @@ no_vbus: info->previous_cable = cable; } + if (info->role_sw && info->vbus_attach != vbus_attach) { + info->vbus_attach = vbus_attach; + /* Setting the role can take a while */ + queue_work(system_long_wq, &info->role_work); + } + return 0; dev_det_ret: @@ -210,6 +287,18 @@ dev_det_ret: return ret; } +static int axp288_extcon_id_evt(struct notifier_block *nb, + unsigned long event, void *param) +{ + struct axp288_extcon_info *info = + container_of(nb, struct axp288_extcon_info, id_nb); + + /* We may not sleep and setting the role can take a while */ + queue_work(system_long_wq, &info->role_work); + + return NOTIFY_OK; +} + static irqreturn_t axp288_extcon_isr(int irq, void *data) { struct axp288_extcon_info *info = data; @@ -231,10 +320,20 @@ static void axp288_extcon_enable(struct axp288_extcon_info *info) BC_GLOBAL_RUN, BC_GLOBAL_RUN); } +static void axp288_put_role_sw(void *data) +{ + struct axp288_extcon_info *info = data; + + cancel_work_sync(&info->role_work); + usb_role_switch_put(info->role_sw); +} + static int axp288_extcon_probe(struct platform_device *pdev) { struct axp288_extcon_info *info; struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent); + struct device *dev = &pdev->dev; + const char *name; int ret, i, pirq; info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); @@ -245,9 +344,33 @@ static int axp288_extcon_probe(struct platform_device *pdev) info->regmap = axp20x->regmap; info->regmap_irqc = axp20x->regmap_irqc; info->previous_cable = EXTCON_NONE; + INIT_WORK(&info->role_work, axp288_usb_role_work); + info->id_nb.notifier_call = axp288_extcon_id_evt; platform_set_drvdata(pdev, info); + info->role_sw = usb_role_switch_get(dev); + if (IS_ERR(info->role_sw)) + return PTR_ERR(info->role_sw); + if (info->role_sw) { + ret = devm_add_action_or_reset(dev, axp288_put_role_sw, info); + if (ret) + return ret; + + name = acpi_dev_get_first_match_name("INT3496", NULL, -1); + if (name) { + info->id_extcon = extcon_get_extcon_dev(name); + if (!info->id_extcon) + return -EPROBE_DEFER; + + dev_info(dev, "controlling USB role\n"); + } else { + dev_info(dev, "controlling USB role based on Vbus presence\n"); + } + } + + info->vbus_attach = axp288_get_vbus_attach(info); + axp288_extcon_log_rsi(info); /* Initialize extcon device */ @@ -289,6 +412,19 @@ static int axp288_extcon_probe(struct platform_device *pdev) } } + if (info->id_extcon) { + ret = devm_extcon_register_notifier_all(dev, info->id_extcon, + &info->id_nb); + if (ret) + return ret; + } + + /* Make sure the role-sw is set correctly before doing BC detection */ + if (info->role_sw) { + queue_work(system_long_wq, &info->role_work); + flush_work(&info->role_work); + } + /* Start charger cable type detection */ axp288_extcon_enable(info); @@ -308,8 +444,32 @@ static struct platform_driver axp288_extcon_driver = { .name = "axp288_extcon", }, }; -module_platform_driver(axp288_extcon_driver); + +static struct device_connection axp288_extcon_role_sw_conn = { + .endpoint[0] = "axp288_extcon", + .endpoint[1] = "intel_xhci_usb_sw-role-switch", + .id = "usb-role-switch", +}; + +static int __init axp288_extcon_init(void) +{ + if (x86_match_cpu(cherry_trail_cpu_ids)) + device_connection_add(&axp288_extcon_role_sw_conn); + + return platform_driver_register(&axp288_extcon_driver); +} +module_init(axp288_extcon_init); + +static void __exit axp288_extcon_exit(void) +{ + if (x86_match_cpu(cherry_trail_cpu_ids)) + device_connection_remove(&axp288_extcon_role_sw_conn); + + platform_driver_unregister(&axp288_extcon_driver); +} +module_exit(axp288_extcon_exit); MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>"); +MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); MODULE_DESCRIPTION("X-Powers AXP288 extcon driver"); MODULE_LICENSE("GPL v2"); |