[PATCH v7 01/24] dm: add helpers needed by the resynced DWC3 code

The resynced DWC3 code calls a few helpers that u-boot did not have.
Add them first so the next commits can use them.

These are not copies of kernel files. They are small u-boot versions of
the Linux v6.16 API that the DWC3 code expects:

- dev_err_probe() from include/linux/device.h.
- device_property_*() from include/linux/property.h. They are thin
  wrappers on the matching dev_read_*() calls.
- struct device gets an of_node member, so the kernel code that carries
  it around still compiles.
- reset_control_assert() and reset_control_deassert() from
  include/linux/reset.h, as empty stubs. u-boot has no reset_control of
  that shape. The DWC3 core only calls reset_control_assert() in
  dwc3_core_exit(), and dwc->reset is never set, because the glue driver
  handles the reset through the DM reset framework. So doing nothing is
  correct here.

Co-developed-by: Jerome Forissier <[email protected]>
Signed-off-by: Jerome Forissier <[email protected]>
Co-developed-by: Jens Wiklander <[email protected]>
Signed-off-by: Jens Wiklander <[email protected]>
Signed-off-by: Anders Roxell <[email protected]>
---
 include/dm/device_compat.h | 13 ++++++++++
 include/dm/read.h          | 51 ++++++++++++++++++++++++++++++++++++++
 include/linux/compat.h     | 15 +++++++++++
 3 files changed, 79 insertions(+)

diff --git a/include/dm/device_compat.h b/include/dm/device_compat.h
index aa9a6fbb5e3f..6b31a72768fd 100644
--- a/include/dm/device_compat.h
+++ b/include/dm/device_compat.h
@@ -119,4 +119,17 @@
 #define dev_vdbg(dev, fmt, ...) \
 	__dev_printk(LOGL_DEBUG_CONTENT, dev, fmt, ##__VA_ARGS__)
 
+#define dev_err_probe(dev, err, fmt, ...) \
+	({ \
+		int _err = (err); \
+		if (_err != -EPROBE_DEFER) { \
+			dev_err(dev, fmt, ##__VA_ARGS__); \
+			dev_err(dev, "[err=%d]", _err); \
+		} else { \
+			dev_dbg(dev, fmt, ##__VA_ARGS__); \
+			dev_dbg(dev, "[err=%d]", _err); \
+		} \
+		_err; \
+	 })
+
 #endif
diff --git a/include/dm/read.h b/include/dm/read.h
index 12dcde6645c7..86c4933fd694 100644
--- a/include/dm/read.h
+++ b/include/dm/read.h
@@ -1273,6 +1273,57 @@ static inline phy_interface_t dev_read_phy_mode(const struct udevice *dev)
 
 #endif /* CONFIG_DM_DEV_READ_INLINE */
 
+static inline int dev_count_u32(const struct udevice *dev,
+				const char *name)
+{
+	return dev_read_u32_array(dev, name, NULL, 0);
+}
+
+/* Linux compatibility */
+
+#define device_property_count_u32 dev_count_u32
+#define device_property_read_bool dev_read_bool
+#define device_property_read_u16 dev_read_u16
+#define device_property_read_u32_array dev_read_u32_array
+#define device_property_read_u32 dev_read_u32
+#define device_property_read_u8 dev_read_u8
+
+static inline int device_property_read_string(const struct udevice *dev,
+					      const char *propname,
+					      const char **val)
+{
+	*val = dev_read_string(dev, propname);
+	if (!*val)
+		return -ENOENT;
+	return 0;
+}
+
+static inline bool device_property_present(const struct udevice *dev,
+					   const char *propname)
+{
+	return (dev_read_size(dev, propname) > 0);
+}
+
+static inline int device_property_count_u8(const struct udevice *dev,
+					   const char *propname)
+{
+	return dev_read_size(dev, propname);
+}
+
+static inline int device_property_read_u8_array(const struct udevice *dev,
+						const char *propname,
+						u8 *out, size_t count)
+{
+	const u8 *ptr = dev_read_u8_array_ptr(dev, propname, count);
+
+	if (!ptr)
+		return -EINVAL;
+
+	memcpy(out, ptr, count);
+
+	return 0;
+}
+
 /**
  * dev_for_each_subnode() - Helper function to iterate through subnodes
  *
diff --git a/include/linux/compat.h b/include/linux/compat.h
index d4ba4d0088a0..16c02260c111 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -297,6 +297,7 @@ struct rw_semaphore { int i; };
 #define up_write(...)			do { } while (0)
 #define down_read(...)			do { } while (0)
 #define up_read(...)			do { } while (0)
+struct device_node;
 struct device {
 	struct device		*parent;
 	struct class		*class;
@@ -305,6 +306,7 @@ struct device {
 	/* This is used from drivers/usb/musb-new subsystem only */
 	void		*driver_data;	/* data private to the driver */
 	void            *device_data;   /* data private to the device */
+	struct device_node	*of_node; /* associated device tree node */
 };
 struct mutex { int i; };
 struct kernel_param { int i; };
@@ -402,4 +404,17 @@ typedef unsigned long dmaaddr_t;
 #define free_irq(irq, data) do {} while (0)
 #define request_irq(nr, f, flags, nm, data) 0
 
+/* From include/linux/reset.h */
+
+struct reset_control;
+
+static inline int reset_control_assert(struct reset_control *rstc)
+{
+	return 0;
+}
+
+static inline int reset_control_deassert(struct reset_control *rstc)
+{
+	return 0;
+}
 #endif
-- 
2.53.0