Merge tag 'soc-drivers-6.16' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-dt into soc/drivers

VT8500 (and FSL) SoC drivers for v6.16

1. VT8500: Add SCC socinfo/hwinfo driver.
2. Cleanup unused function in PowerPC Freescale QE driver to have W=1
   builds warnings free.

* tag 'soc-drivers-6.16' of https://git.kernel.org/pub/scm/linux/kernel/git/krzk/linux-dt:
  soc: fsl: qe: remove unused qe_ic_from_irq function
  ARM: vt8500: MAINTAINERS: Include vt8500 soc driver in maintainers entry
  soc: Add VIA/WonderMedia SoC identification driver
  dt-bindings: hwinfo: Add VIA/WonderMedia SoC identification

Link: https://lore.kernel.org/r/20250513104216.25803-6-krzysztof.kozlowski@linaro.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

8 files changed, 187 insertions, 5 deletions

diff --git a/Documentation/devicetree/bindings/hwinfo/via,vt8500-scc-id.yaml b/Documentation/devicetree/bindings/hwinfo/via,vt8500-scc-id.yaml
new file mode 100644
index 000000000000..b0f425a4a882
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwinfo/via,vt8500-scc-id.yaml
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/hwinfo/via,vt8500-scc-id.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: VIA/WonderMedia SoC system configuration information
+
+maintainers:
+  - Alexey Charkov <alchark@gmail.com>
+
+description:
+  The system configuration controller on VIA/WonderMedia SoC's contains a chip
+  identifier and revision used to differentiate between different hardware
+  versions of on-chip IP blocks having their own peculiarities which may or
+  may not be captured by their respective DT compatible strings
+
+properties:
+  compatible:
+    items:
+      - const: via,vt8500-scc-id
+
+  reg:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+additionalProperties: false
+
+examples:
+  - |
+    chipid@d8120000 {
+        compatible = "via,vt8500-scc-id";
+        reg = <0xd8120000 0x4>;
+    };
diff --git a/MAINTAINERS b/MAINTAINERS
index bd1fce741296..8ab070582af9 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3428,6 +3428,7 @@ M:	Alexey Charkov <alchark@gmail.com>
 M:	Krzysztof Kozlowski <krzk@kernel.org>
 L:	linux-arm-kernel@lists.infradead.org (moderated for non-subscribers)
 S:	Odd Fixes
+F:	Documentation/devicetree/bindings/hwinfo/via,vt8500-scc-id.yaml
 F:	Documentation/devicetree/bindings/i2c/i2c-wmt.txt
 F:	arch/arm/boot/dts/vt8500/
 F:	arch/arm/mach-vt8500/
@@ -3436,6 +3437,7 @@ F:	drivers/i2c/busses/i2c-viai2c-wmt.c
 F:	drivers/mmc/host/wmt-sdmmc.c
 F:	drivers/pwm/pwm-vt8500.c
 F:	drivers/rtc/rtc-vt8500.c
+F:	drivers/soc/vt8500/
 F:	drivers/tty/serial/vt8500_serial.c
 F:	drivers/video/fbdev/vt8500lcdfb.*
 F:	drivers/video/fbdev/wm8505fb*
diff --git a/drivers/soc/Kconfig b/drivers/soc/Kconfig
index 6a8daeb8c4b9..37ca3f094f89 100644
--- a/drivers/soc/Kconfig
+++ b/drivers/soc/Kconfig
@@ -28,6 +28,7 @@ source "drivers/soc/tegra/Kconfig"
 source "drivers/soc/ti/Kconfig"
 source "drivers/soc/ux500/Kconfig"
 source "drivers/soc/versatile/Kconfig"
+source "drivers/soc/vt8500/Kconfig"
 source "drivers/soc/xilinx/Kconfig"
 
 endmenu
diff --git a/drivers/soc/Makefile b/drivers/soc/Makefile
index 2037a8695cb2..777255401252 100644
--- a/drivers/soc/Makefile
+++ b/drivers/soc/Makefile
@@ -34,4 +34,5 @@ obj-$(CONFIG_ARCH_TEGRA)	+= tegra/
 obj-y				+= ti/
 obj-$(CONFIG_ARCH_U8500)	+= ux500/
 obj-y				+= versatile/
+obj-y				+= vt8500/
 obj-y				+= xilinx/
diff --git a/drivers/soc/fsl/qe/qe_ic.c b/drivers/soc/fsl/qe/qe_ic.c
index 77bf0e83ffcc..7eab15553f2f 100644
--- a/drivers/soc/fsl/qe/qe_ic.c
+++ b/drivers/soc/fsl/qe/qe_ic.c
@@ -232,11 +232,6 @@ static inline void qe_ic_write(__be32  __iomem *base, unsigned int reg,
 	iowrite32be(value, base + (reg >> 2));
 }
 
-static inline struct qe_ic *qe_ic_from_irq(unsigned int virq)
-{
-	return irq_get_chip_data(virq);
-}
-
 static inline struct qe_ic *qe_ic_from_irq_data(struct irq_data *d)
 {
 	return irq_data_get_irq_chip_data(d);
diff --git a/drivers/soc/vt8500/Kconfig b/drivers/soc/vt8500/Kconfig
new file mode 100644
index 000000000000..b4cc0ba1128b
--- /dev/null
+++ b/drivers/soc/vt8500/Kconfig
@@ -0,0 +1,19 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+if ARCH_VT8500 || COMPILE_TEST
+
+menu "VIA/WonderMedia SoC drivers"
+
+config WMT_SOCINFO
+	bool "VIA/WonderMedia SoC Information driver"
+	default ARCH_VT8500
+	select SOC_BUS
+	help
+	  Say yes to support decoding of VIA/WonderMedia system configuration
+	  register information. This currently includes just the chip ID register
+	  which helps identify the exact hardware revision of the SoC the kernel
+	  is running on (to know if any revision-specific quirks are required)
+
+endmenu
+
+endif
diff --git a/drivers/soc/vt8500/Makefile b/drivers/soc/vt8500/Makefile
new file mode 100644
index 000000000000..05964c5f2890
--- /dev/null
+++ b/drivers/soc/vt8500/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_WMT_SOCINFO)	+= wmt-socinfo.o
diff --git a/drivers/soc/vt8500/wmt-socinfo.c b/drivers/soc/vt8500/wmt-socinfo.c
new file mode 100644
index 000000000000..461f8c1ae56e
--- /dev/null
+++ b/drivers/soc/vt8500/wmt-socinfo.c
@@ -0,0 +1,125 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright 2025 Alexey Charkov <alchark@gmail.com>
+ * Based on aspeed-socinfo.c
+ */
+
+#include <linux/dev_printk.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/sys_soc.h>
+
+static const struct {
+	const char *name;
+	const u32 id;
+} chip_id_table[] = {
+	/* VIA */
+	{ "VT8420", 0x3300 },
+	{ "VT8430", 0x3357 },
+	{ "VT8500", 0x3400 },
+
+	/* WonderMedia */
+	{ "WM8425", 0x3429 },
+	{ "WM8435", 0x3437 },
+	{ "WM8440", 0x3451 },
+	{ "WM8505", 0x3426 },
+	{ "WM8650", 0x3465 },
+	{ "WM8750", 0x3445 },
+	{ "WM8850", 0x3481 },
+	{ "WM8880", 0x3498 },
+};
+
+static const char *sccid_to_name(u32 sccid)
+{
+	u32 id = sccid >> 16;
+	unsigned int i;
+
+	for (i = 0 ; i < ARRAY_SIZE(chip_id_table) ; ++i) {
+		if (chip_id_table[i].id == id)
+			return chip_id_table[i].name;
+	}
+
+	return "Unknown";
+}
+
+static int wmt_socinfo_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct soc_device_attribute *attrs;
+	struct soc_device *soc_dev;
+	char letter, digit;
+	void __iomem *reg;
+	u32 sccid;
+
+	reg = devm_of_iomap(&pdev->dev, np, 0, NULL);
+	if (IS_ERR(reg))
+		return PTR_ERR(reg);
+
+	sccid = readl(reg);
+
+	attrs = devm_kzalloc(&pdev->dev, sizeof(*attrs), GFP_KERNEL);
+	if (!attrs)
+		return -ENOMEM;
+
+	/*
+	 * Machine: VIA APC Rock
+	 * Family: WM8850
+	 * Revision: A2
+	 * SoC ID: raw silicon revision id (34810103 in hexadecimal)
+	 */
+
+	attrs->family = sccid_to_name(sccid);
+
+	letter = (sccid >> 8) & 0xf;
+	letter = (letter - 1) + 'A';
+	digit = sccid & 0xff;
+	digit = (digit - 1) + '0';
+	attrs->revision = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+					 "%c%c", letter, digit);
+
+	attrs->soc_id = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%08x", sccid);
+
+	if (!attrs->revision || !attrs->soc_id)
+		return -ENOMEM;
+
+	soc_dev = soc_device_register(attrs);
+	if (IS_ERR(soc_dev))
+		return PTR_ERR(soc_dev);
+
+	dev_info(&pdev->dev,
+		 "VIA/WonderMedia %s rev %s (%s)\n",
+		 attrs->family,
+		 attrs->revision,
+		 attrs->soc_id);
+
+	platform_set_drvdata(pdev, soc_dev);
+	return 0;
+}
+
+static void wmt_socinfo_remove(struct platform_device *pdev)
+{
+	struct soc_device *soc_dev = platform_get_drvdata(pdev);
+
+	soc_device_unregister(soc_dev);
+}
+
+static const struct of_device_id wmt_socinfo_ids[] = {
+	{ .compatible = "via,vt8500-scc-id" },
+	{ /* Sentinel */ },
+};
+
+static struct platform_driver wmt_socinfo = {
+	.probe = wmt_socinfo_probe,
+	.remove = wmt_socinfo_remove,
+	.driver = {
+		.name = "wmt-socinfo",
+		.of_match_table = wmt_socinfo_ids,
+	},
+};
+module_platform_driver(wmt_socinfo);
+
+MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
+MODULE_DESCRIPTION("VIA/WonderMedia socinfo driver");
+MODULE_LICENSE("GPL");