diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/usb/phy/phy-tahvo.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/usb/phy/phy-tahvo.c')
-rw-r--r-- | drivers/usb/phy/phy-tahvo.c | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-tahvo.c b/drivers/usb/phy/phy-tahvo.c new file mode 100644 index 000000000..da63d7e4d --- /dev/null +++ b/drivers/usb/phy/phy-tahvo.c @@ -0,0 +1,440 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Tahvo USB transceiver driver + * + * Copyright (C) 2005-2006 Nokia Corporation + * + * Parts copied from isp1301_omap.c. + * Copyright (C) 2004 Texas Instruments + * Copyright (C) 2004 David Brownell + * + * Original driver written by Juha Yrjölä, Tony Lindgren and Timo Teräs. + * Modified for Retu/Tahvo MFD by Aaro Koskinen. + */ + +#include <linux/io.h> +#include <linux/clk.h> +#include <linux/usb.h> +#include <linux/extcon-provider.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/usb/otg.h> +#include <linux/mfd/retu.h> +#include <linux/usb/gadget.h> +#include <linux/platform_device.h> + +#define DRIVER_NAME "tahvo-usb" + +#define TAHVO_REG_IDSR 0x02 +#define TAHVO_REG_USBR 0x06 + +#define USBR_SLAVE_CONTROL (1 << 8) +#define USBR_VPPVIO_SW (1 << 7) +#define USBR_SPEED (1 << 6) +#define USBR_REGOUT (1 << 5) +#define USBR_MASTER_SW2 (1 << 4) +#define USBR_MASTER_SW1 (1 << 3) +#define USBR_SLAVE_SW (1 << 2) +#define USBR_NSUSPEND (1 << 1) +#define USBR_SEMODE (1 << 0) + +#define TAHVO_MODE_HOST 0 +#define TAHVO_MODE_PERIPHERAL 1 + +struct tahvo_usb { + struct platform_device *pt_dev; + struct usb_phy phy; + int vbus_state; + struct mutex serialize; + struct clk *ick; + int irq; + int tahvo_mode; + struct extcon_dev *extcon; +}; + +static const unsigned int tahvo_cable[] = { + EXTCON_USB, + EXTCON_USB_HOST, + + EXTCON_NONE, +}; + +static ssize_t vbus_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct tahvo_usb *tu = dev_get_drvdata(device); + return sprintf(buf, "%s\n", tu->vbus_state ? "on" : "off"); +} +static DEVICE_ATTR_RO(vbus); + +static void check_vbus_state(struct tahvo_usb *tu) +{ + struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent); + int reg, prev_state; + + reg = retu_read(rdev, TAHVO_REG_IDSR); + if (reg & TAHVO_STAT_VBUS) { + switch (tu->phy.otg->state) { + case OTG_STATE_B_IDLE: + /* Enable the gadget driver */ + if (tu->phy.otg->gadget) + usb_gadget_vbus_connect(tu->phy.otg->gadget); + tu->phy.otg->state = OTG_STATE_B_PERIPHERAL; + usb_phy_set_event(&tu->phy, USB_EVENT_ENUMERATED); + break; + case OTG_STATE_A_IDLE: + /* + * Session is now valid assuming the USB hub is driving + * Vbus. + */ + tu->phy.otg->state = OTG_STATE_A_HOST; + break; + default: + break; + } + dev_info(&tu->pt_dev->dev, "USB cable connected\n"); + } else { + switch (tu->phy.otg->state) { + case OTG_STATE_B_PERIPHERAL: + if (tu->phy.otg->gadget) + usb_gadget_vbus_disconnect(tu->phy.otg->gadget); + tu->phy.otg->state = OTG_STATE_B_IDLE; + usb_phy_set_event(&tu->phy, USB_EVENT_NONE); + break; + case OTG_STATE_A_HOST: + tu->phy.otg->state = OTG_STATE_A_IDLE; + break; + default: + break; + } + dev_info(&tu->pt_dev->dev, "USB cable disconnected\n"); + } + + prev_state = tu->vbus_state; + tu->vbus_state = reg & TAHVO_STAT_VBUS; + if (prev_state != tu->vbus_state) { + extcon_set_state_sync(tu->extcon, EXTCON_USB, tu->vbus_state); + sysfs_notify(&tu->pt_dev->dev.kobj, NULL, "vbus_state"); + } +} + +static void tahvo_usb_become_host(struct tahvo_usb *tu) +{ + struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent); + + extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, true); + + /* Power up the transceiver in USB host mode */ + retu_write(rdev, TAHVO_REG_USBR, USBR_REGOUT | USBR_NSUSPEND | + USBR_MASTER_SW2 | USBR_MASTER_SW1); + tu->phy.otg->state = OTG_STATE_A_IDLE; + + check_vbus_state(tu); +} + +static void tahvo_usb_stop_host(struct tahvo_usb *tu) +{ + tu->phy.otg->state = OTG_STATE_A_IDLE; +} + +static void tahvo_usb_become_peripheral(struct tahvo_usb *tu) +{ + struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent); + + extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, false); + + /* Power up transceiver and set it in USB peripheral mode */ + retu_write(rdev, TAHVO_REG_USBR, USBR_SLAVE_CONTROL | USBR_REGOUT | + USBR_NSUSPEND | USBR_SLAVE_SW); + tu->phy.otg->state = OTG_STATE_B_IDLE; + + check_vbus_state(tu); +} + +static void tahvo_usb_stop_peripheral(struct tahvo_usb *tu) +{ + if (tu->phy.otg->gadget) + usb_gadget_vbus_disconnect(tu->phy.otg->gadget); + tu->phy.otg->state = OTG_STATE_B_IDLE; +} + +static void tahvo_usb_power_off(struct tahvo_usb *tu) +{ + struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent); + + /* Disable gadget controller if any */ + if (tu->phy.otg->gadget) + usb_gadget_vbus_disconnect(tu->phy.otg->gadget); + + /* Power off transceiver */ + retu_write(rdev, TAHVO_REG_USBR, 0); + tu->phy.otg->state = OTG_STATE_UNDEFINED; +} + +static int tahvo_usb_set_suspend(struct usb_phy *dev, int suspend) +{ + struct tahvo_usb *tu = container_of(dev, struct tahvo_usb, phy); + struct retu_dev *rdev = dev_get_drvdata(tu->pt_dev->dev.parent); + u16 w; + + dev_dbg(&tu->pt_dev->dev, "%s\n", __func__); + + w = retu_read(rdev, TAHVO_REG_USBR); + if (suspend) + w &= ~USBR_NSUSPEND; + else + w |= USBR_NSUSPEND; + retu_write(rdev, TAHVO_REG_USBR, w); + + return 0; +} + +static int tahvo_usb_set_host(struct usb_otg *otg, struct usb_bus *host) +{ + struct tahvo_usb *tu = container_of(otg->usb_phy, struct tahvo_usb, + phy); + + mutex_lock(&tu->serialize); + + if (host == NULL) { + if (tu->tahvo_mode == TAHVO_MODE_HOST) + tahvo_usb_power_off(tu); + otg->host = NULL; + mutex_unlock(&tu->serialize); + return 0; + } + + if (tu->tahvo_mode == TAHVO_MODE_HOST) { + otg->host = NULL; + tahvo_usb_become_host(tu); + } + + otg->host = host; + + mutex_unlock(&tu->serialize); + + return 0; +} + +static int tahvo_usb_set_peripheral(struct usb_otg *otg, + struct usb_gadget *gadget) +{ + struct tahvo_usb *tu = container_of(otg->usb_phy, struct tahvo_usb, + phy); + + mutex_lock(&tu->serialize); + + if (!gadget) { + if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL) + tahvo_usb_power_off(tu); + tu->phy.otg->gadget = NULL; + mutex_unlock(&tu->serialize); + return 0; + } + + tu->phy.otg->gadget = gadget; + if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL) + tahvo_usb_become_peripheral(tu); + + mutex_unlock(&tu->serialize); + + return 0; +} + +static irqreturn_t tahvo_usb_vbus_interrupt(int irq, void *_tu) +{ + struct tahvo_usb *tu = _tu; + + mutex_lock(&tu->serialize); + check_vbus_state(tu); + mutex_unlock(&tu->serialize); + + return IRQ_HANDLED; +} + +static ssize_t otg_mode_show(struct device *device, + struct device_attribute *attr, char *buf) +{ + struct tahvo_usb *tu = dev_get_drvdata(device); + + switch (tu->tahvo_mode) { + case TAHVO_MODE_HOST: + return sprintf(buf, "host\n"); + case TAHVO_MODE_PERIPHERAL: + return sprintf(buf, "peripheral\n"); + } + + return -EINVAL; +} + +static ssize_t otg_mode_store(struct device *device, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct tahvo_usb *tu = dev_get_drvdata(device); + int r; + + mutex_lock(&tu->serialize); + if (count >= 4 && strncmp(buf, "host", 4) == 0) { + if (tu->tahvo_mode == TAHVO_MODE_PERIPHERAL) + tahvo_usb_stop_peripheral(tu); + tu->tahvo_mode = TAHVO_MODE_HOST; + if (tu->phy.otg->host) { + dev_info(device, "HOST mode: host controller present\n"); + tahvo_usb_become_host(tu); + } else { + dev_info(device, "HOST mode: no host controller, powering off\n"); + tahvo_usb_power_off(tu); + } + r = strlen(buf); + } else if (count >= 10 && strncmp(buf, "peripheral", 10) == 0) { + if (tu->tahvo_mode == TAHVO_MODE_HOST) + tahvo_usb_stop_host(tu); + tu->tahvo_mode = TAHVO_MODE_PERIPHERAL; + if (tu->phy.otg->gadget) { + dev_info(device, "PERIPHERAL mode: gadget driver present\n"); + tahvo_usb_become_peripheral(tu); + } else { + dev_info(device, "PERIPHERAL mode: no gadget driver, powering off\n"); + tahvo_usb_power_off(tu); + } + r = strlen(buf); + } else { + r = -EINVAL; + } + mutex_unlock(&tu->serialize); + + return r; +} +static DEVICE_ATTR_RW(otg_mode); + +static struct attribute *tahvo_attrs[] = { + &dev_attr_vbus.attr, + &dev_attr_otg_mode.attr, + NULL +}; +ATTRIBUTE_GROUPS(tahvo); + +static int tahvo_usb_probe(struct platform_device *pdev) +{ + struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent); + struct tahvo_usb *tu; + int ret; + + tu = devm_kzalloc(&pdev->dev, sizeof(*tu), GFP_KERNEL); + if (!tu) + return -ENOMEM; + + tu->phy.otg = devm_kzalloc(&pdev->dev, sizeof(*tu->phy.otg), + GFP_KERNEL); + if (!tu->phy.otg) + return -ENOMEM; + + tu->pt_dev = pdev; + + /* Default mode */ +#ifdef CONFIG_TAHVO_USB_HOST_BY_DEFAULT + tu->tahvo_mode = TAHVO_MODE_HOST; +#else + tu->tahvo_mode = TAHVO_MODE_PERIPHERAL; +#endif + + mutex_init(&tu->serialize); + + tu->ick = devm_clk_get(&pdev->dev, "usb_l4_ick"); + if (!IS_ERR(tu->ick)) + clk_enable(tu->ick); + + /* + * Set initial state, so that we generate kevents only on state changes. + */ + tu->vbus_state = retu_read(rdev, TAHVO_REG_IDSR) & TAHVO_STAT_VBUS; + + tu->extcon = devm_extcon_dev_allocate(&pdev->dev, tahvo_cable); + if (IS_ERR(tu->extcon)) { + dev_err(&pdev->dev, "failed to allocate memory for extcon\n"); + ret = PTR_ERR(tu->extcon); + goto err_disable_clk; + } + + ret = devm_extcon_dev_register(&pdev->dev, tu->extcon); + if (ret) { + dev_err(&pdev->dev, "could not register extcon device: %d\n", + ret); + goto err_disable_clk; + } + + /* Set the initial cable state. */ + extcon_set_state_sync(tu->extcon, EXTCON_USB_HOST, + tu->tahvo_mode == TAHVO_MODE_HOST); + extcon_set_state_sync(tu->extcon, EXTCON_USB, tu->vbus_state); + + /* Create OTG interface */ + tahvo_usb_power_off(tu); + tu->phy.dev = &pdev->dev; + tu->phy.otg->state = OTG_STATE_UNDEFINED; + tu->phy.label = DRIVER_NAME; + tu->phy.set_suspend = tahvo_usb_set_suspend; + + tu->phy.otg->usb_phy = &tu->phy; + tu->phy.otg->set_host = tahvo_usb_set_host; + tu->phy.otg->set_peripheral = tahvo_usb_set_peripheral; + + ret = usb_add_phy(&tu->phy, USB_PHY_TYPE_USB2); + if (ret < 0) { + dev_err(&pdev->dev, "cannot register USB transceiver: %d\n", + ret); + goto err_disable_clk; + } + + dev_set_drvdata(&pdev->dev, tu); + + tu->irq = ret = platform_get_irq(pdev, 0); + if (ret < 0) + goto err_remove_phy; + ret = request_threaded_irq(tu->irq, NULL, tahvo_usb_vbus_interrupt, + IRQF_ONESHOT, + "tahvo-vbus", tu); + if (ret) { + dev_err(&pdev->dev, "could not register tahvo-vbus irq: %d\n", + ret); + goto err_remove_phy; + } + + return 0; + +err_remove_phy: + usb_remove_phy(&tu->phy); +err_disable_clk: + if (!IS_ERR(tu->ick)) + clk_disable(tu->ick); + + return ret; +} + +static int tahvo_usb_remove(struct platform_device *pdev) +{ + struct tahvo_usb *tu = platform_get_drvdata(pdev); + + free_irq(tu->irq, tu); + usb_remove_phy(&tu->phy); + if (!IS_ERR(tu->ick)) + clk_disable(tu->ick); + + return 0; +} + +static struct platform_driver tahvo_usb_driver = { + .probe = tahvo_usb_probe, + .remove = tahvo_usb_remove, + .driver = { + .name = "tahvo-usb", + .dev_groups = tahvo_groups, + }, +}; +module_platform_driver(tahvo_usb_driver); + +MODULE_DESCRIPTION("Tahvo USB transceiver driver"); +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Juha Yrjölä, Tony Lindgren, and Timo Teräs"); +MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>"); |