[PATCH v2 1/4] i2c: designware: Create shared header hosting driver name

[Florian Fainelli]

We have a number of drivers that reference the string "i2c_designware"
towards two goals:

- ensure their device gets bound to the i2c_designware platform_driver
- create a clock lookup reference that matches the i2c_designware
  instance number for the i2c-designware-platdrv.c driver to be able to
  lookup the input reference clock

Since this string is copied in a bunch of different places and since it
is possible to get this named wrong (see [1] and [2]) with unintended
consequences, create a header file that hosts that define for other
drivers to use and all agree on the correct name to use.

[1]:
https://lore.kernel.org/all/20240422084109.3201-1-duanqiangwen@xxxxxxxxxxxxx/
[2]:
https://lore.kernel.org/all/20240422084109.3201-2-duanqiangwen@xxxxxxxxxxxxx/

Signed-off-by: Florian Fainelli <florian.fainelli@xxxxxxxxxxxx>
---
 MAINTAINERS                                  |  1 +
 drivers/i2c/busses/i2c-designware-pcidrv.c   |  3 ++-
 drivers/i2c/busses/i2c-designware-platdrv.c  |  5 +++--
 include/linux/platform_data/i2c-designware.h | 11 +++++++++++
 4 files changed, 17 insertions(+), 3 deletions(-)
 create mode 100644 include/linux/platform_data/i2c-designware.h

diff --git a/MAINTAINERS b/MAINTAINERS
index 2d5acd6d98c4..da1b39df2b94 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -21438,6 +21438,7 @@ R:	Jan Dabros <jsd@xxxxxxxxxxxx>
 L:	linux-i2c@xxxxxxxxxxxxxxx
 S:	Supported
 F:	drivers/i2c/busses/i2c-designware-*
+F:	include/linux/platform_data/i2c-designware.h
 
 SYNOPSYS DESIGNWARE MMC/SD/SDIO DRIVER
 M:	Jaehoon Chung <jh80.chung@xxxxxxxxxxx>
diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c
index 9be9a2658e1f..32d6f338a1ea 100644
--- a/drivers/i2c/busses/i2c-designware-pcidrv.c
+++ b/drivers/i2c/busses/i2c-designware-pcidrv.c
@@ -19,6 +19,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/pci.h>
+#include <linux/platform_data/i2c-designware.h>
 #include <linux/pm_runtime.h>
 #include <linux/power_supply.h>
 #include <linux/sched.h>
@@ -425,7 +426,7 @@ static struct pci_driver dw_i2c_driver = {
 module_pci_driver(dw_i2c_driver);
 
 /* Work with hotplug and coldplug */
-MODULE_ALIAS("i2c_designware-pci");
+MODULE_ALIAS(I2C_DESIGNWARE_NAME "-pci");
 MODULE_AUTHOR("Baruch Siach <baruch@xxxxxxxxxx>");
 MODULE_DESCRIPTION("Synopsys DesignWare PCI I2C bus adapter");
 MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 4ab41ba39d55..8aa2bf274d78 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -22,6 +22,7 @@
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of.h>
+#include <linux/platform_data/i2c-designware.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
@@ -480,13 +481,13 @@ static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
 };
 
 /* Work with hotplug and coldplug */
-MODULE_ALIAS("platform:i2c_designware");
+MODULE_ALIAS("platform:" I2C_DESIGNWARE_NAME);
 
 static struct platform_driver dw_i2c_driver = {
 	.probe = dw_i2c_plat_probe,
 	.remove_new = dw_i2c_plat_remove,
 	.driver		= {
-		.name	= "i2c_designware",
+		.name	= I2C_DESIGNWARE_NAME,
 		.of_match_table = of_match_ptr(dw_i2c_of_match),
 		.acpi_match_table = ACPI_PTR(dw_i2c_acpi_match),
 		.pm	= pm_ptr(&dw_i2c_dev_pm_ops),
diff --git a/include/linux/platform_data/i2c-designware.h b/include/linux/platform_data/i2c-designware.h
new file mode 100644
index 000000000000..e385b6d70a04
--- /dev/null
+++ b/include/linux/platform_data/i2c-designware.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __I2C_DESIGNWARE_PDATA_H__
+#define __I2C_DESIGNWARE_PDATA_H__
+
+/* This is the i2c-designware-platdrv.c platform driver name. This name is used
+ * to bind the device to the driver, as well as by the driver itself to request
+ * the input reference clock
+ */
+#define I2C_DESIGNWARE_NAME	"i2c_designware"
+
+#endif /* __I2C_DESIGNWARE_PDATA_H__ */
-- 
2.34.1