[PATCH 18/21] asm-generic/io.h: add iowrite{8,16}_32 accessors

Tudor Ambarus tudor.ambarus at linaro.org
Tue Jan 23 07:34:17 PST 2024


This will allow devices that require 32 bits register accesses to write
data in chunks of 8 or 16 bits.

One SoC that requires 32 bit register accesses is the google gs101. A
typical use case is SPI, where the clients can request transfers in words
of 8 bits.

Signed-off-by: Tudor Ambarus <tudor.ambarus at linaro.org>
---
 include/asm-generic/io.h | 50 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index bac63e874c7b..1e224d1ccc98 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -476,6 +476,21 @@ static inline void writesb(volatile void __iomem *addr, const void *buffer,
 }
 #endif
 
+#ifndef writesb_l
+#define writesb_l writesb_l
+static inline void writesb_l(volatile void __iomem *addr, const void *buffer,
+			     unsigned int count)
+{
+	if (count) {
+		const u8 *buf = buffer;
+
+		do {
+			__raw_writel(*buf++, addr);
+		} while (--count);
+	}
+}
+#endif
+
 #ifndef writesw
 #define writesw writesw
 static inline void writesw(volatile void __iomem *addr, const void *buffer,
@@ -491,6 +506,21 @@ static inline void writesw(volatile void __iomem *addr, const void *buffer,
 }
 #endif
 
+#ifndef writesw_l
+#define writesw_l writesw_l
+static inline void writesw_l(volatile void __iomem *addr, const void *buffer,
+			     unsigned int count)
+{
+	if (count) {
+		const u16 *buf = buffer;
+
+		do {
+			__raw_writel(*buf++, addr);
+		} while (--count);
+	}
+}
+#endif
+
 #ifndef writesl
 #define writesl writesl
 static inline void writesl(volatile void __iomem *addr, const void *buffer,
@@ -956,6 +986,16 @@ static inline void iowrite8_rep(volatile void __iomem *addr,
 }
 #endif
 
+#ifndef iowrite8_32_rep
+#define iowrite8_32_rep iowrite8_32_rep
+static inline void iowrite8_32_rep(volatile void __iomem *addr,
+				   const void *buffer,
+				   unsigned int count)
+{
+	writesb_l(addr, buffer, count);
+}
+#endif
+
 #ifndef iowrite16_rep
 #define iowrite16_rep iowrite16_rep
 static inline void iowrite16_rep(volatile void __iomem *addr,
@@ -966,6 +1006,16 @@ static inline void iowrite16_rep(volatile void __iomem *addr,
 }
 #endif
 
+#ifndef iowrite16_32_rep
+#define iowrite16_32_rep iowrite16_32_rep
+static inline void iowrite16_32_rep(volatile void __iomem *addr,
+				    const void *buffer,
+				    unsigned int count)
+{
+	writesw_l(addr, buffer, count);
+}
+#endif
+
 #ifndef iowrite32_rep
 #define iowrite32_rep iowrite32_rep
 static inline void iowrite32_rep(volatile void __iomem *addr,
-- 
2.43.0.429.g432eaa2c6b-goog




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