diff options
Diffstat (limited to 'drivers/platform/chrome/wilco_ec/core.c')
| -rw-r--r-- | drivers/platform/chrome/wilco_ec/core.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/drivers/platform/chrome/wilco_ec/core.c b/drivers/platform/chrome/wilco_ec/core.c new file mode 100644 index 000000000000..05e1e2be1c91 --- /dev/null +++ b/drivers/platform/chrome/wilco_ec/core.c @@ -0,0 +1,136 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Core driver for Wilco Embedded Controller + * + * Copyright 2018 Google LLC + * + * This is the entry point for the drivers that control the Wilco EC. + * This driver is responsible for several tasks: + * - Initialize the register interface that is used by wilco_ec_mailbox() + * - Create a platform device which is picked up by the debugfs driver + * - Create a platform device which is picked up by the RTC driver + */ + +#include <linux/acpi.h> +#include <linux/device.h> +#include <linux/ioport.h> +#include <linux/module.h> +#include <linux/platform_data/wilco-ec.h> +#include <linux/platform_device.h> + +#include "../cros_ec_lpc_mec.h" + +#define DRV_NAME "wilco-ec" + +static struct resource *wilco_get_resource(struct platform_device *pdev, + int index) +{ + struct device *dev = &pdev->dev; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_IO, index); + if (!res) { + dev_dbg(dev, "Couldn't find IO resource %d\n", index); + return res; + } + + return devm_request_region(dev, res->start, resource_size(res), + dev_name(dev)); +} + +static int wilco_ec_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct wilco_ec_device *ec; + int ret; + + ec = devm_kzalloc(dev, sizeof(*ec), GFP_KERNEL); + if (!ec) + return -ENOMEM; + + platform_set_drvdata(pdev, ec); + ec->dev = dev; + mutex_init(&ec->mailbox_lock); + + /* Largest data buffer size requirement is extended data response */ + ec->data_size = sizeof(struct wilco_ec_response) + + EC_MAILBOX_DATA_SIZE_EXTENDED; + ec->data_buffer = devm_kzalloc(dev, ec->data_size, GFP_KERNEL); + if (!ec->data_buffer) + return -ENOMEM; + + /* Prepare access to IO regions provided by ACPI */ + ec->io_data = wilco_get_resource(pdev, 0); /* Host Data */ + ec->io_command = wilco_get_resource(pdev, 1); /* Host Command */ + ec->io_packet = wilco_get_resource(pdev, 2); /* MEC EMI */ + if (!ec->io_data || !ec->io_command || !ec->io_packet) + return -ENODEV; + + /* Initialize cros_ec register interface for communication */ + cros_ec_lpc_mec_init(ec->io_packet->start, + ec->io_packet->start + EC_MAILBOX_DATA_SIZE); + + /* + * Register a child device that will be found by the debugfs driver. + * Ignore failure. + */ + ec->debugfs_pdev = platform_device_register_data(dev, + "wilco-ec-debugfs", + PLATFORM_DEVID_AUTO, + NULL, 0); + + /* Register a child device that will be found by the RTC driver. */ + ec->rtc_pdev = platform_device_register_data(dev, "rtc-wilco-ec", + PLATFORM_DEVID_AUTO, + NULL, 0); + if (IS_ERR(ec->rtc_pdev)) { + dev_err(dev, "Failed to create RTC platform device\n"); + ret = PTR_ERR(ec->rtc_pdev); + goto unregister_debugfs; + } + + return 0; + +unregister_debugfs: + if (ec->debugfs_pdev) + platform_device_unregister(ec->debugfs_pdev); + cros_ec_lpc_mec_destroy(); + return ret; +} + +static int wilco_ec_remove(struct platform_device *pdev) +{ + struct wilco_ec_device *ec = platform_get_drvdata(pdev); + + platform_device_unregister(ec->rtc_pdev); + if (ec->debugfs_pdev) + platform_device_unregister(ec->debugfs_pdev); + + /* Teardown cros_ec interface */ + cros_ec_lpc_mec_destroy(); + + return 0; +} + +static const struct acpi_device_id wilco_ec_acpi_device_ids[] = { + { "GOOG000C", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, wilco_ec_acpi_device_ids); + +static struct platform_driver wilco_ec_driver = { + .driver = { + .name = DRV_NAME, + .acpi_match_table = wilco_ec_acpi_device_ids, + }, + .probe = wilco_ec_probe, + .remove = wilco_ec_remove, +}; + +module_platform_driver(wilco_ec_driver); + +MODULE_AUTHOR("Nick Crews <ncrews@chromium.org>"); +MODULE_AUTHOR("Duncan Laurie <dlaurie@chromium.org>"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("ChromeOS Wilco Embedded Controller driver"); +MODULE_ALIAS("platform:" DRV_NAME); |