Clock "csiclk" gets divided by 2 * CSI_CLKSEL_CKS in order to generate
the serial clock (output from master), with CSI_CLKSEL_CKS ranging from
0x1 (that means "csiclk" is divided by 2) to 0x3FFF ("csiclk" is divided
by 32766). CSI_CKS_MAX is used for referring to the setting
corresponding to the maximum frequency divider.
Value 0x3FFF for CSI_CKS_MAX doesn't really means much to the reader
without an explanation and a more readable definition.
Add a comment with a meaningful description and also replace value
0x3FFF with the corresponding GENMASK, to make it very clear what the
macro means.
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@xxxxxxxxxxx>
---
drivers/spi/spi-rzv2m-csi.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi-rzv2m-csi.c b/drivers/spi/spi-rzv2m-csi.c
index 3931045a85eb..621774949bde 100644
--- a/drivers/spi/spi-rzv2m-csi.c
+++ b/drivers/spi/spi-rzv2m-csi.c
@@ -65,7 +65,12 @@
#define CSI_FIFO_SIZE_BYTES 32
#define CSI_FIFO_HALF_SIZE 16
#define CSI_EN_DIS_TIMEOUT_US 100
-#define CSI_CKS_MAX 0x3FFF
+/*
+ * Clock "csiclk" gets divided by 2 * CSI_CLKSEL_CKS in order to generate the
+ * serial clock (output from master), with CSI_CLKSEL_CKS ranging from 0x1 (that
+ * means "csiclk" is divided by 2) to 0x3FFF ("csiclk" is divided by 32766).
+ */
+#define CSI_CKS_MAX GENMASK(13, 0)
#define UNDERRUN_ERROR BIT(0)
#define OVERFLOW_ERROR BIT(1)
--
2.34.1
