Merge: Add i2c-i801 support for Intel Panther Lake

MR: https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/merge_requests/6620

JIRA: https://issues.redhat.com/browse/RHEL-47426



Signed-off-by: David Arcari <darcari@redhat.com>

Approved-by: Tony Camuso <tcamuso@redhat.com>
Approved-by: Mark Langsdorf <mlangsdo@redhat.com>
Approved-by: Steve Best <sbest@redhat.com>
Approved-by: CKI KWF Bot <cki-ci-bot+kwf-gitlab-com@redhat.com>

Merged-by: Augusto Caringi <acaringi@redhat.com>

Documentation/i2c/busses/i2c-i801.rst

@@ -49,6 +49,7 @@ Supported adapters:
   * Intel Meteor Lake (SOC and PCH)
   * Intel Birch Stream (SOC)
   * Intel Arrow Lake (SOC)
+  * Intel Panther Lake (SOC)
 
    Datasheets: Publicly available at the Intel website
 

drivers/i2c/busses/Kconfig

@@ -160,10 +160,19 @@ config I2C_I801
 	    Meteor Lake (SOC and PCH)
 	    Birch Stream (SOC)
 	    Arrow Lake (SOC)
+	    Panther Lake (SOC)
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-i801.
 
+config I2C_I801_MUX
+	def_bool I2C_I801
+	depends on DMI && I2C_MUX_GPIO
+	depends on !(I2C_I801=y && I2C_MUX=m)
+	help
+	  Optional support for multiplexed SMBUS on certain systems with
+	  more than 8 memory slots.
+
 config I2C_ISCH
 	tristate "Intel SCH SMBus 1.0"
 	depends on PCI

drivers/platform/x86/dell/Kconfig

@@ -140,7 +140,8 @@ config DELL_SMBIOS_SMM
 config DELL_SMO8800
 	tristate "Dell Latitude freefall driver (ACPI SMO88XX)"
 	default m
-	depends on ACPI
+	depends on I2C
+	depends on ACPI || COMPILE_TEST
 	help
 	  Say Y here if you want to support SMO88XX freefall devices
 	  on Dell Latitude laptops.

drivers/platform/x86/dell/Makefile

@@ -14,6 +14,7 @@ dell-smbios-objs			:= dell-smbios-base.o
 dell-smbios-$(CONFIG_DELL_SMBIOS_WMI)	+= dell-smbios-wmi.o
 dell-smbios-$(CONFIG_DELL_SMBIOS_SMM)	+= dell-smbios-smm.o
 obj-$(CONFIG_DELL_SMO8800)		+= dell-smo8800.o
+obj-$(CONFIG_DELL_SMO8800)		+= dell-lis3lv02d.o
 obj-$(CONFIG_DELL_WMI)			+= dell-wmi.o
 dell-wmi-objs				:= dell-wmi-base.o
 dell-wmi-$(CONFIG_DELL_WMI_PRIVACY)	+= dell-wmi-privacy.o

drivers/platform/x86/dell/dell-lis3lv02d.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * lis3lv02d i2c-client instantiation for ACPI SMO88xx devices without I2C resources.
+ *
+ *  Copyright (C) 2024 Hans de Goede <hansg@kernel.org>
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/device/bus.h>
+#include <linux/dmi.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/platform_device.h>
+#include <linux/workqueue.h>
+#include "dell-smo8800-ids.h"
+
+#define LIS3_WHO_AM_I 0x0f
+
+#define DELL_LIS3LV02D_DMI_ENTRY(product_name, i2c_addr)                 \
+	{                                                                \
+		.matches = {                                             \
+			DMI_EXACT_MATCH(DMI_SYS_VENDOR, "Dell Inc."),    \
+			DMI_EXACT_MATCH(DMI_PRODUCT_NAME, product_name), \
+		},                                                       \
+		.driver_data = (void *)(uintptr_t)(i2c_addr),            \
+	}
+
+/*
+ * Accelerometer's I2C address is not specified in DMI nor ACPI,
+ * so it is needed to define mapping table based on DMI product names.
+ */
+static const struct dmi_system_id lis3lv02d_devices[] __initconst = {
+	/*
+	 * Dell platform team told us that these Latitude devices have
+	 * ST microelectronics accelerometer at I2C address 0x29.
+	 */
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E5250",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E5450",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E5550",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E6440",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E6440 ATG", 0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E6540",     0x29),
+	/*
+	 * Additional individual entries were added after verification.
+	 */
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude 5480",      0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E6330",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Latitude E6430",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Precision 3540",     0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Precision M6800",    0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("Vostro V131",        0x1d),
+	DELL_LIS3LV02D_DMI_ENTRY("Vostro 5568",        0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("XPS 15 7590",        0x29),
+	DELL_LIS3LV02D_DMI_ENTRY("XPS 15 9550",        0x29),
+	{ }
+};
+
+static u8 i2c_addr;
+static struct i2c_client *i2c_dev;
+static bool notifier_registered;
+
+static bool probe_i2c_addr;
+module_param(probe_i2c_addr, bool, 0444);
+MODULE_PARM_DESC(probe_i2c_addr, "Probe the i801 I2C bus for the accelerometer on models where the address is unknown, this may be dangerous.");
+
+static int detect_lis3lv02d(struct i2c_adapter *adap, unsigned short addr)
+{
+	union i2c_smbus_data smbus_data;
+	int err;
+
+	dev_info(&adap->dev, "Probing for lis3lv02d on address 0x%02x\n", addr);
+
+	err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, LIS3_WHO_AM_I,
+			     I2C_SMBUS_BYTE_DATA, &smbus_data);
+	if (err < 0)
+		return 0; /* Not found */
+
+	/* valid who-am-i values are from drivers/misc/lis3lv02d/lis3lv02d.c */
+	switch (smbus_data.byte) {
+	case 0x32:
+	case 0x33:
+	case 0x3a:
+	case 0x3b:
+		break;
+	default:
+		dev_warn(&adap->dev, "Unknown who-am-i register value 0x%02x\n",
+			 smbus_data.byte);
+		return 0; /* Not found */
+	}
+
+	dev_info(&adap->dev,
+		 "Detected lis3lv02d on address 0x%02x, please report this upstream to platform-driver-x86@vger.kernel.org so that a quirk can be added\n",
+		 addr);
+
+	return 1; /* Found */
+}
+
+static bool i2c_adapter_is_main_i801(struct i2c_adapter *adap)
+{
+	/*
+	 * Only match the main I801 adapter and reject secondary adapters
+	 * which names start with "SMBus I801 IDF adapter".
+	 */
+	return strstarts(adap->name, "SMBus I801 adapter");
+}
+
+static int find_i801(struct device *dev, void *data)
+{
+	struct i2c_adapter *adap, **adap_ret = data;
+
+	adap = i2c_verify_adapter(dev);
+	if (!adap)
+		return 0;
+
+	if (!i2c_adapter_is_main_i801(adap))
+		return 0;
+
+	*adap_ret = i2c_get_adapter(adap->nr);
+	return 1;
+}
+
+static void instantiate_i2c_client(struct work_struct *work)
+{
+	struct i2c_board_info info = { };
+	struct i2c_adapter *adap = NULL;
+
+	if (i2c_dev)
+		return;
+
+	/*
+	 * bus_for_each_dev() and not i2c_for_each_dev() to avoid
+	 * a deadlock when find_i801() calls i2c_get_adapter().
+	 */
+	bus_for_each_dev(&i2c_bus_type, NULL, &adap, find_i801);
+	if (!adap)
+		return;
+
+	strscpy(info.type, "lis3lv02d", I2C_NAME_SIZE);
+
+	if (i2c_addr) {
+		info.addr = i2c_addr;
+		i2c_dev = i2c_new_client_device(adap, &info);
+	} else {
+		/* First try address 0x29 (most used) and then try 0x1d */
+		static const unsigned short addr_list[] = { 0x29, 0x1d, I2C_CLIENT_END };
+
+		i2c_dev = i2c_new_scanned_device(adap, &info, addr_list, detect_lis3lv02d);
+	}
+
+	if (IS_ERR(i2c_dev)) {
+		dev_err(&adap->dev, "error %ld registering i2c_client\n", PTR_ERR(i2c_dev));
+		i2c_dev = NULL;
+	} else {
+		dev_dbg(&adap->dev, "registered lis3lv02d on address 0x%02x\n", info.addr);
+	}
+
+	i2c_put_adapter(adap);
+}
+static DECLARE_WORK(i2c_work, instantiate_i2c_client);
+
+static int i2c_bus_notify(struct notifier_block *nb, unsigned long action, void *data)
+{
+	struct device *dev = data;
+	struct i2c_client *client;
+	struct i2c_adapter *adap;
+
+	switch (action) {
+	case BUS_NOTIFY_ADD_DEVICE:
+		adap = i2c_verify_adapter(dev);
+		if (!adap)
+			break;
+
+		if (i2c_adapter_is_main_i801(adap))
+			queue_work(system_long_wq, &i2c_work);
+		break;
+	case BUS_NOTIFY_REMOVED_DEVICE:
+		client = i2c_verify_client(dev);
+		if (!client)
+			break;
+
+		if (i2c_dev == client) {
+			dev_dbg(&client->adapter->dev, "lis3lv02d i2c_client removed\n");
+			i2c_dev = NULL;
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+static struct notifier_block i2c_nb = { .notifier_call = i2c_bus_notify };
+
+static int __init match_acpi_device_ids(struct device *dev, const void *data)
+{
+	return acpi_match_device(data, dev) ? 1 : 0;
+}
+
+static int __init dell_lis3lv02d_init(void)
+{
+	const struct dmi_system_id *lis3lv02d_dmi_id;
+	struct device *dev;
+	int err;
+
+	/*
+	 * First check for a matching platform_device. This protects against
+	 * SMO88xx ACPI fwnodes which actually do have an I2C resource, which
+	 * will already have an i2c_client instantiated (not a platform_device).
+	 */
+	dev = bus_find_device(&platform_bus_type, NULL, smo8800_ids, match_acpi_device_ids);
+	if (!dev) {
+		pr_debug("No SMO88xx platform-device found\n");
+		return 0;
+	}
+	put_device(dev);
+
+	lis3lv02d_dmi_id = dmi_first_match(lis3lv02d_devices);
+	if (!lis3lv02d_dmi_id && !probe_i2c_addr) {
+		pr_warn("accelerometer is present on SMBus but its address is unknown, skipping registration\n");
+		pr_info("Pass dell_lis3lv02d.probe_i2c_addr=1 on the kernel command line to probe, this may be dangerous!\n");
+		return 0;
+	}
+
+	if (lis3lv02d_dmi_id)
+		i2c_addr = (long)lis3lv02d_dmi_id->driver_data;
+
+	/*
+	 * Register i2c-bus notifier + queue initial scan for lis3lv02d
+	 * i2c_client instantiation.
+	 */
+	err = bus_register_notifier(&i2c_bus_type, &i2c_nb);
+	if (err)
+		return err;
+
+	notifier_registered = true;
+
+	queue_work(system_long_wq, &i2c_work);
+	return 0;
+}
+module_init(dell_lis3lv02d_init);
+
+static void __exit dell_lis3lv02d_module_exit(void)
+{
+	if (!notifier_registered)
+		return;
+
+	bus_unregister_notifier(&i2c_bus_type, &i2c_nb);
+	cancel_work_sync(&i2c_work);
+	i2c_unregister_device(i2c_dev);
+}
+module_exit(dell_lis3lv02d_module_exit);
+
+MODULE_DESCRIPTION("lis3lv02d i2c-client instantiation for ACPI SMO88xx devices");
+MODULE_AUTHOR("Hans de Goede <hansg@kernel.org>");
+MODULE_LICENSE("GPL");

drivers/platform/x86/dell/dell-smo8800-ids.h

+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *  ACPI SMO88XX lis3lv02d freefall / accelerometer device-ids.
+ *
+ *  Copyright (C) 2012 Sonal Santan <sonal.santan@gmail.com>
+ *  Copyright (C) 2014 Pali Rohár <pali@kernel.org>
+ */
+#ifndef _DELL_SMO8800_IDS_H_
+#define _DELL_SMO8800_IDS_H_
+
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+
+static const struct acpi_device_id smo8800_ids[] = {
+	{ "SMO8800" },
+	{ "SMO8801" },
+	{ "SMO8810" },
+	{ "SMO8811" },
+	{ "SMO8820" },
+	{ "SMO8821" },
+	{ "SMO8830" },
+	{ "SMO8831" },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, smo8800_ids);
+
+#endif

drivers/platform/x86/dell/dell-smo8800.c

@@ -10,13 +10,14 @@
 
 #define DRIVER_NAME "smo8800"
 
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/acpi.h>
+#include <linux/fs.h>
 #include <linux/interrupt.h>
+#include <linux/kernel.h>
 #include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
 #include <linux/uaccess.h>
-#include <linux/fs.h>
+#include "dell-smo8800-ids.h"
 
 struct smo8800_device {
 	u32 irq;                     /* acpi device irq */
@@ -44,37 +45,6 @@ static irqreturn_t smo8800_interrupt_thread(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-static acpi_status smo8800_get_resource(struct acpi_resource *resource,
-					void *context)
-{
-	struct acpi_resource_extended_irq *irq;
-
-	if (resource->type != ACPI_RESOURCE_TYPE_EXTENDED_IRQ)
-		return AE_OK;
-
-	irq = &resource->data.extended_irq;
-	if (!irq || !irq->interrupt_count)
-		return AE_OK;
-
-	*((u32 *)context) = irq->interrupts[0];
-	return AE_CTRL_TERMINATE;
-}
-
-static u32 smo8800_get_irq(struct acpi_device *device)
-{
-	u32 irq = 0;
-	acpi_status status;
-
-	status = acpi_walk_resources(device->handle, METHOD_NAME__CRS,
-				     smo8800_get_resource, &irq);
-	if (ACPI_FAILURE(status)) {
-		dev_err(&device->dev, "acpi_walk_resources failed\n");
-		return 0;
-	}
-
-	return irq;
-}
-
 static ssize_t smo8800_misc_read(struct file *file, char __user *buf,
 				 size_t count, loff_t *pos)
 {
@@ -97,10 +67,7 @@ static ssize_t smo8800_misc_read(struct file *file, char __user *buf,
 
 	retval = 1;
 
-	if (data < 255)
-		byte_data = data;
-	else
-		byte_data = 255;
+	byte_data = min_t(u32, data, 255);
 
 	if (put_user(byte_data, buf))
 		retval = -EFAULT;
@@ -136,7 +103,7 @@ static const struct file_operations smo8800_misc_fops = {
 	.release = smo8800_misc_release,
 };
 
-static int smo8800_add(struct acpi_device *device)
+static int smo8800_probe(struct platform_device *device)
 {
 	int err;
 	struct smo8800_device *smo8800;
@@ -160,14 +127,12 @@ static int smo8800_add(struct acpi_device *device)
 		return err;
 	}
 
-	device->driver_data = smo8800;
+	platform_set_drvdata(device, smo8800);
 
-	smo8800->irq = smo8800_get_irq(device);
-	if (!smo8800->irq) {
-		dev_err(&device->dev, "failed to obtain IRQ\n");
-		err = -EINVAL;
+	err = platform_get_irq(device, 0);
+	if (err < 0)
 		goto error;
-	}
+	smo8800->irq = err;
 
 	err = request_threaded_irq(smo8800->irq, smo8800_interrupt_quick,
 				   smo8800_interrupt_thread,
@@ -189,42 +154,24 @@ static int smo8800_add(struct acpi_device *device)
 	return err;
 }
 
-static void smo8800_remove(struct acpi_device *device)
+static void smo8800_remove(struct platform_device *device)
 {
-	struct smo8800_device *smo8800 = device->driver_data;
+	struct smo8800_device *smo8800 = platform_get_drvdata(device);
 
 	free_irq(smo8800->irq, smo8800);
 	misc_deregister(&smo8800->miscdev);
 	dev_dbg(&device->dev, "device /dev/freefall unregistered\n");
 }
 
-/* NOTE: Keep this list in sync with drivers/i2c/busses/i2c-i801.c */
-static const struct acpi_device_id smo8800_ids[] = {
-	{ "SMO8800", 0 },
-	{ "SMO8801", 0 },
-	{ "SMO8810", 0 },
-	{ "SMO8811", 0 },
-	{ "SMO8820", 0 },
-	{ "SMO8821", 0 },
-	{ "SMO8830", 0 },
-	{ "SMO8831", 0 },
-	{ "", 0 },
-};
-
-MODULE_DEVICE_TABLE(acpi, smo8800_ids);
-
-static struct acpi_driver smo8800_driver = {
-	.name = DRIVER_NAME,
-	.class = "Latitude",
-	.ids = smo8800_ids,
-	.ops = {
-		.add = smo8800_add,
-		.remove = smo8800_remove,
+static struct platform_driver smo8800_driver = {
+	.probe = smo8800_probe,
+	.remove_new = smo8800_remove,
+	.driver = {
+		.name = DRIVER_NAME,
+		.acpi_match_table = smo8800_ids,
 	},
-	.owner = THIS_MODULE,
 };
-
-module_acpi_driver(smo8800_driver);
+module_platform_driver(smo8800_driver);
 
 MODULE_DESCRIPTION("Dell Latitude freefall driver (ACPI SMO88XX)");
 MODULE_LICENSE("GPL");

include/linux/acpi.h

@@ -1549,4 +1549,9 @@ static inline bool acpi_node_backed_by_real_pxm(int nid)
 }
 #endif
 
+static inline void acpi_use_parent_companion(struct device *dev)
+{
+	ACPI_COMPANION_SET(dev, ACPI_COMPANION(dev->parent));
+}
+
 #endif	/*_LINUX_ACPI_H*/