From c2138b25d5a42e527588bd26cb2409352d8c0743 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Thu, 30 Dec 2021 00:14:26 +0100 Subject: [PATCH] platform/x86: x86-android-tablets: Add support for instantiating serdevs Add support for instantiating serdevs, this is necessary on some boards where the serdev info in the DSDT has issues. Signed-off-by: Hans de Goede Link: https://lore.kernel.org/r/20211229231431.437982-8-hdegoede@redhat.com --- drivers/platform/x86/Kconfig | 2 +- drivers/platform/x86/x86-android-tablets.c | 101 +++++++++++++++++++++++++++++ 2 files changed, 102 insertions(+), 1 deletion(-) diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index b9a73df1820f..833abec54644 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -1006,7 +1006,7 @@ config TOUCHSCREEN_DMI config X86_ANDROID_TABLETS tristate "X86 Android tablet support" - depends on I2C && ACPI && GPIOLIB + depends on I2C && SERIAL_DEV_BUS && ACPI && GPIOLIB help X86 tablets which ship with Android as (part of) the factory image typically have various problems with their DSDTs. The factory kernels diff --git a/drivers/platform/x86/x86-android-tablets.c b/drivers/platform/x86/x86-android-tablets.c index 4bcad05d4039..5267e57c4fea 100644 --- a/drivers/platform/x86/x86-android-tablets.c +++ b/drivers/platform/x86/x86-android-tablets.c @@ -21,6 +21,7 @@ #include #include #include +#include #include /* For gpio_get_desc() which is EXPORT_SYMBOL_GPL() */ #include "../../gpio/gpiolib.h" @@ -127,11 +128,26 @@ struct x86_i2c_client_info { struct x86_acpi_irq_data irq_data; }; +struct x86_serdev_info { + const char *ctrl_hid; + const char *ctrl_uid; + const char *ctrl_devname; + /* + * ATM the serdev core only supports of or ACPI matching; and sofar all + * Android x86 tablets DSDTs have usable serdev nodes, but sometimes + * under the wrong controller. So we just tie the existing serdev ACPI + * node to the right controller. + */ + const char *serdev_hid; +}; + struct x86_dev_info { const struct x86_i2c_client_info *i2c_client_info; const struct platform_device_info *pdev_info; + const struct x86_serdev_info *serdev_info; int i2c_client_count; int pdev_count; + int serdev_count; }; /* @@ -273,8 +289,10 @@ MODULE_DEVICE_TABLE(dmi, x86_android_tablet_ids); static int i2c_client_count; static int pdev_count; +static int serdev_count; static struct i2c_client **i2c_clients; static struct platform_device **pdevs; +static struct serdev_device **serdevs; static __init int x86_instantiate_i2c_client(const struct x86_dev_info *dev_info, int idx) @@ -310,10 +328,78 @@ static __init int x86_instantiate_i2c_client(const struct x86_dev_info *dev_info return 0; } +static __init int x86_instantiate_serdev(const struct x86_serdev_info *info, int idx) +{ + struct acpi_device *ctrl_adev, *serdev_adev; + struct serdev_device *serdev; + struct device *ctrl_dev; + int ret = -ENODEV; + + ctrl_adev = acpi_dev_get_first_match_dev(info->ctrl_hid, info->ctrl_uid, -1); + if (!ctrl_adev) { + pr_err("error could not get %s/%s ctrl adev\n", + info->ctrl_hid, info->ctrl_uid); + return -ENODEV; + } + + serdev_adev = acpi_dev_get_first_match_dev(info->serdev_hid, NULL, -1); + if (!serdev_adev) { + pr_err("error could not get %s serdev adev\n", info->serdev_hid); + goto put_ctrl_adev; + } + + /* get_first_physical_node() returns a weak ref, no need to put() it */ + ctrl_dev = acpi_get_first_physical_node(ctrl_adev); + if (!ctrl_dev) { + pr_err("error could not get %s/%s ctrl physical dev\n", + info->ctrl_hid, info->ctrl_uid); + goto put_serdev_adev; + } + + /* ctrl_dev now points to the controller's parent, get the controller */ + ctrl_dev = device_find_child_by_name(ctrl_dev, info->ctrl_devname); + if (!ctrl_dev) { + pr_err("error could not get %s/%s %s ctrl dev\n", + info->ctrl_hid, info->ctrl_uid, info->ctrl_devname); + goto put_serdev_adev; + } + + serdev = serdev_device_alloc(to_serdev_controller(ctrl_dev)); + if (!serdev) { + ret = -ENOMEM; + goto put_serdev_adev; + } + + ACPI_COMPANION_SET(&serdev->dev, serdev_adev); + acpi_device_set_enumerated(serdev_adev); + + ret = serdev_device_add(serdev); + if (ret) { + dev_err(&serdev->dev, "error %d adding serdev\n", ret); + serdev_device_put(serdev); + goto put_serdev_adev; + } + + serdevs[idx] = serdev; + +put_serdev_adev: + acpi_dev_put(serdev_adev); +put_ctrl_adev: + acpi_dev_put(ctrl_adev); + return ret; +} + static void x86_android_tablet_cleanup(void) { int i; + for (i = 0; i < serdev_count; i++) { + if (serdevs[i]) + serdev_device_remove(serdevs[i]); + } + + kfree(serdevs); + for (i = 0; i < pdev_count; i++) platform_device_unregister(pdevs[i]); @@ -365,6 +451,21 @@ static __init int x86_android_tablet_init(void) } } + serdevs = kcalloc(dev_info->serdev_count, sizeof(*serdevs), GFP_KERNEL); + if (!serdevs) { + x86_android_tablet_cleanup(); + return -ENOMEM; + } + + serdev_count = dev_info->serdev_count; + for (i = 0; i < serdev_count; i++) { + ret = x86_instantiate_serdev(&dev_info->serdev_info[i], i); + if (ret < 0) { + x86_android_tablet_cleanup(); + return ret; + } + } + return 0; } -- 2.11.0