mediatek: add support for SPI calibration

Newer MediaTek's SoCs need SPI calibration routines for SPI to work
reliably. Import patches for that from MediaTek's SDK.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

1 files changed, 41 insertions, 0 deletions

diff --git a/target/linux/mediatek/patches-5.15/433-drivers-spi-mem-Add-spi-calibration-hook.patch b/target/linux/mediatek/patches-5.15/433-drivers-spi-mem-Add-spi-calibration-hook.patch
new file mode 100644
index 0000000000..aaacab0131
--- /dev/null
+++ b/target/linux/mediatek/patches-5.15/433-drivers-spi-mem-Add-spi-calibration-hook.patch
@@ -0,0 +1,41 @@
+From 06640a5da2973318c06e516da16a5b579622e7c5 Mon Sep 17 00:00:00 2001
+From: "SkyLake.Huang" <skylake.huang@mediatek.com>
+Date: Thu, 23 Jun 2022 18:37:55 +0800
+Subject: [PATCH 3/6] drivers: spi-mem: Add spi calibration hook
+
+Signed-off-by: SkyLake.Huang <skylake.huang@mediatek.com>
+---
+ drivers/spi/spi-mem.c       | 8 ++++++++
+ include/linux/spi/spi-mem.h | 4 ++++
+ 2 files changed, 12 insertions(+)
+
+--- a/drivers/spi/spi-mem.c
++++ b/drivers/spi/spi-mem.c
+@@ -410,6 +410,14 @@ int spi_mem_exec_op(struct spi_mem *mem,
+ }
+ EXPORT_SYMBOL_GPL(spi_mem_exec_op);
+ 
++int spi_mem_do_calibration(struct spi_mem *mem,
++	int (*cal_read)(void *priv, u32 *addr, int addrlen, u8 *buf, int readlen),
++	void *priv)
++{
++	return spi_do_calibration(mem->spi->controller, mem->spi, cal_read, priv);
++}
++EXPORT_SYMBOL_GPL(spi_mem_do_calibration);
++
+ /**
+  * spi_mem_get_name() - Return the SPI mem device name to be used by the
+  *			upper layer if necessary
+--- a/include/linux/spi/spi-mem.h
++++ b/include/linux/spi/spi-mem.h
+@@ -366,6 +366,10 @@ bool spi_mem_supports_op(struct spi_mem
+ int spi_mem_exec_op(struct spi_mem *mem,
+ 		    const struct spi_mem_op *op);
+ 
++int spi_mem_do_calibration(struct spi_mem *mem,
++			int (*cal_read)(void *, u32 *, int, u8 *, int),
++			void *priv);
++
+ const char *spi_mem_get_name(struct spi_mem *mem);
+ 
+ struct spi_mem_dirmap_desc *