[v7,2/3] usb: typec: ucsi: Implement ChromeOS UCSI driver

Message ID	20241115155234.1587589-3-ukaszb@chromium.org (mailing list archive)
State	New
Headers	show Received: from mail-ej1-f48.google.com (mail-ej1-f48.google.com [209.85.218.48]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5B75C1D5AD3 for <chrome-platform@lists.linux.dev>; Fri, 15 Nov 2024 15:52:44 +0000 (UTC) From: =?utf-8?q?=C5=81ukasz_Bartosik?= <ukaszb@chromium.org> To: Heikki Krogerus <heikki.krogerus@linux.intel.com>, Greg Kroah-Hartman <gregkh@linuxfoundation.org>, Benson Leung <bleung@chromium.org> Cc: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>, Jameson Thies <jthies@google.com>, Pavan Holla <pholla@chromium.org>, Tzung-Bi Shih <tzungbi@kernel.org>, linux-usb@vger.kernel.org, chrome-platform@lists.linux.dev Subject: [PATCH v7 2/3] usb: typec: ucsi: Implement ChromeOS UCSI driver Date: Fri, 15 Nov 2024 15:52:33 +0000 Message-ID: <20241115155234.1587589-3-ukaszb@chromium.org> In-Reply-To: <20241115155234.1587589-1-ukaszb@chromium.org> References: <20241115155234.1587589-1-ukaszb@chromium.org> Precedence: bulk MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit
Series	usb: typec: Implement UCSI driver for ChromeOS \| expand [v7,0/3] usb: typec: Implement UCSI driver for ChromeOS [v7,1/3] platform/chrome: Update ChromeOS EC header for UCSI [v7,2/3] usb: typec: ucsi: Implement ChromeOS UCSI driver [v7,3/3] usb: typec: cros_ec_ucsi: Recover from write timeouts

diff --git a/MAINTAINERS b/MAINTAINERS index 21fdaa19229a..b5c57bb68c44 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5389,6 +5389,13 @@ L: chrome-platform@lists.linux.dev S: Maintained F: drivers/watchdog/cros_ec_wdt.c +CHROMEOS UCSI DRIVER +M: Abhishek Pandit-Subedi <abhishekpandit@chromium.org> +M: Łukasz Bartosik <ukaszb@chromium.org> +L: chrome-platform@lists.linux.dev +S: Maintained +F: drivers/usb/typec/ucsi/cros_ec_ucsi.c + CHRONTEL CH7322 CEC DRIVER M: Joe Tessler <jrt@google.com> L: linux-media@vger.kernel.org diff --git a/drivers/usb/typec/ucsi/Kconfig b/drivers/usb/typec/ucsi/Kconfig index 680e1b87b152..75559601fe8f 100644 --- a/drivers/usb/typec/ucsi/Kconfig +++ b/drivers/usb/typec/ucsi/Kconfig @@ -69,6 +69,19 @@ config UCSI_PMIC_GLINK To compile the driver as a module, choose M here: the module will be called ucsi_glink. +config CROS_EC_UCSI + tristate "UCSI Driver for ChromeOS EC" + depends on MFD_CROS_EC_DEV + depends on CROS_USBPD_NOTIFY + depends on !EXTCON_TCSS_CROS_EC + default MFD_CROS_EC_DEV + help + This driver enables UCSI support for a ChromeOS EC. The EC is + expected to implement a PPM. + + To compile the driver as a module, choose M here: the module + will be called cros_ec_ucsi. + config UCSI_LENOVO_YOGA_C630 tristate "UCSI Interface Driver for Lenovo Yoga C630" depends on EC_LENOVO_YOGA_C630 diff --git a/drivers/usb/typec/ucsi/Makefile b/drivers/usb/typec/ucsi/Makefile index aed41d23887b..be98a879104d 100644 --- a/drivers/usb/typec/ucsi/Makefile +++ b/drivers/usb/typec/ucsi/Makefile @@ -21,4 +21,5 @@ obj-$(CONFIG_UCSI_ACPI) += ucsi_acpi.o obj-$(CONFIG_UCSI_CCG) += ucsi_ccg.o obj-$(CONFIG_UCSI_STM32G0) += ucsi_stm32g0.o obj-$(CONFIG_UCSI_PMIC_GLINK) += ucsi_glink.o +obj-$(CONFIG_CROS_EC_UCSI) += cros_ec_ucsi.o obj-$(CONFIG_UCSI_LENOVO_YOGA_C630) += ucsi_yoga_c630.o diff --git a/drivers/usb/typec/ucsi/cros_ec_ucsi.c b/drivers/usb/typec/ucsi/cros_ec_ucsi.c new file mode 100644 index 000000000000..aae0bf106494 --- /dev/null +++ b/drivers/usb/typec/ucsi/cros_ec_ucsi.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * UCSI driver for ChromeOS EC + * + * Copyright 2024 Google LLC. + */ + +#include <linux/container_of.h> +#include <linux/dev_printk.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/platform_data/cros_ec_commands.h> +#include <linux/platform_data/cros_usbpd_notify.h> +#include <linux/platform_data/cros_ec_proto.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/wait.h> + +#include "ucsi.h" + +/* + * Maximum size in bytes of a UCSI message between AP and EC + */ +#define MAX_EC_DATA_SIZE 256 + +/* + * Maximum time in miliseconds the cros_ec_ucsi driver + * will wait for a response to a command or and ack. + */ +#define WRITE_TMO_MS 5000 + +struct cros_ucsi_data { + struct device *dev; + struct ucsi *ucsi; + + struct cros_ec_device *ec; + struct notifier_block nb; + struct work_struct work; + + struct completion complete; + unsigned long flags; +}; + +static int cros_ucsi_read(struct ucsi *ucsi, unsigned int offset, void *val, + size_t val_len) +{ + struct cros_ucsi_data *udata = ucsi_get_drvdata(ucsi); + struct ec_params_ucsi_ppm_get req = { + .offset = offset, + .size = val_len, + }; + int ret; + + if (val_len > MAX_EC_DATA_SIZE) { + dev_err(udata->dev, "Can't read %zu bytes. Too big.", val_len); + return -EINVAL; + } + + ret = cros_ec_cmd(udata->ec, 0, EC_CMD_UCSI_PPM_GET, + &req, sizeof(req), val, val_len); + if (ret < 0) { + dev_warn(udata->dev, "Failed to send EC message UCSI_PPM_GET: error=%d", ret); + return ret; + } + return 0; +} + +static int cros_ucsi_read_version(struct ucsi *ucsi, u16 *version) +{ + return cros_ucsi_read(ucsi, UCSI_VERSION, version, sizeof(*version)); +} + +static int cros_ucsi_read_cci(struct ucsi *ucsi, u32 *cci) +{ + return cros_ucsi_read(ucsi, UCSI_CCI, cci, sizeof(*cci)); +} + +static int cros_ucsi_read_message_in(struct ucsi *ucsi, void *val, + size_t val_len) +{ + return cros_ucsi_read(ucsi, UCSI_MESSAGE_IN, val, val_len); +} + +static int cros_ucsi_async_control(struct ucsi *ucsi, u64 cmd) +{ + struct cros_ucsi_data *udata = ucsi_get_drvdata(ucsi); + u8 ec_buf[sizeof(struct ec_params_ucsi_ppm_set) + sizeof(cmd)]; + struct ec_params_ucsi_ppm_set *req = (struct ec_params_ucsi_ppm_set *) ec_buf; + int ret; + + req->offset = UCSI_CONTROL; + memcpy(req->data, &cmd, sizeof(cmd)); + ret = cros_ec_cmd(udata->ec, 0, EC_CMD_UCSI_PPM_SET, + req, sizeof(ec_buf), NULL, 0); + if (ret < 0) { + dev_warn(udata->dev, "Failed to send EC message UCSI_PPM_SET: error=%d", ret); + return ret; + } + return 0; +} + +static int cros_ucsi_sync_control(struct ucsi *ucsi, u64 cmd) +{ + return ucsi_sync_control_common(ucsi, cmd); +} + +struct ucsi_operations cros_ucsi_ops = { + .read_version = cros_ucsi_read_version, + .read_cci = cros_ucsi_read_cci, + .read_message_in = cros_ucsi_read_message_in, + .async_control = cros_ucsi_async_control, + .sync_control = cros_ucsi_sync_control, +}; + +static void cros_ucsi_work(struct work_struct *work) +{ + struct cros_ucsi_data *udata = container_of(work, struct cros_ucsi_data, work); + u32 cci; + + if (cros_ucsi_read_cci(udata->ucsi, &cci)) + return; + + ucsi_notify_common(udata->ucsi, cci); +} + +static int cros_ucsi_event(struct notifier_block *nb, + unsigned long host_event, void *_notify) +{ + struct cros_ucsi_data *udata = container_of(nb, struct cros_ucsi_data, nb); + + if (!(host_event & PD_EVENT_PPM)) + return NOTIFY_OK; + + dev_dbg(udata->dev, "UCSI notification received"); + flush_work(&udata->work); + schedule_work(&udata->work); + + return NOTIFY_OK; +} + +static void cros_ucsi_destroy(struct cros_ucsi_data *udata) +{ + cros_usbpd_unregister_notify(&udata->nb); + cancel_work_sync(&udata->work); + ucsi_destroy(udata->ucsi); +} + +static int cros_ucsi_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct cros_ec_dev *ec_data = dev_get_drvdata(dev->parent); + struct cros_ucsi_data *udata; + int ret; + + udata = devm_kzalloc(dev, sizeof(*udata), GFP_KERNEL); + if (!udata) + return -ENOMEM; + + udata->dev = dev; + + udata->ec = ec_data->ec_dev; + if (!udata->ec) { + dev_err(dev, "couldn't find parent EC device"); + return -ENODEV; + } + + platform_set_drvdata(pdev, udata); + + INIT_WORK(&udata->work, cros_ucsi_work); + init_completion(&udata->complete); + + udata->ucsi = ucsi_create(dev, &cros_ucsi_ops); + if (IS_ERR(udata->ucsi)) { + dev_err(dev, "failed to allocate UCSI instance"); + return PTR_ERR(udata->ucsi); + } + + ucsi_set_drvdata(udata->ucsi, udata); + + udata->nb.notifier_call = cros_ucsi_event; + ret = cros_usbpd_register_notify(&udata->nb); + if (ret) { + dev_err(dev, "failed to register notifier: error=%d", ret); + ucsi_destroy(udata->ucsi); + return ret; + } + + ret = ucsi_register(udata->ucsi); + if (ret) { + dev_err(dev, "failed to register UCSI: error=%d", ret); + cros_ucsi_destroy(udata); + return ret; + } + + return 0; +} + +static void cros_ucsi_remove(struct platform_device *dev) +{ + struct cros_ucsi_data *udata = platform_get_drvdata(dev); + + ucsi_unregister(udata->ucsi); + cros_ucsi_destroy(udata); +} + +static int __maybe_unused cros_ucsi_suspend(struct device *dev) +{ + struct cros_ucsi_data *udata = dev_get_drvdata(dev); + + cancel_work_sync(&udata->work); + + return 0; +} + +static void __maybe_unused cros_ucsi_complete(struct device *dev) +{ + struct cros_ucsi_data *udata = dev_get_drvdata(dev); + + ucsi_resume(udata->ucsi); +} + +static const struct dev_pm_ops cros_ucsi_pm_ops = { +#ifdef CONFIG_PM_SLEEP + .suspend = cros_ucsi_suspend, + .complete = cros_ucsi_complete, +#endif +}; + +static const struct platform_device_id cros_ucsi_id[] = { + { KBUILD_MODNAME, 0 }, + {} +}; +MODULE_DEVICE_TABLE(platform, cros_ucsi_id); + +static struct platform_driver cros_ucsi_driver = { + .driver = { + .name = KBUILD_MODNAME, + .pm = &cros_ucsi_pm_ops, + }, + .id_table = cros_ucsi_id, + .probe = cros_ucsi_probe, + .remove = cros_ucsi_remove, +}; + +module_platform_driver(cros_ucsi_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("UCSI driver for ChromeOS EC");

[v7,2/3] usb: typec: ucsi: Implement ChromeOS UCSI driver

Commit Message

Comments

Patch