From: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
To: Mark Brown <broonie@kernel.org>,
Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Fabrizio Castro <fabrizio.castro.jz@renesas.com>,
Andy Shevchenko <andy.shevchenko@gmail.com>,
linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org,
Chris Paterson <Chris.Paterson2@renesas.com>,
Biju Das <biju.das@bp.renesas.com>,
Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>,
linux-renesas-soc@vger.kernel.org
Subject: [PATCH 03/10] spi: rzv2m-csi: Rework CSI_CKS_MAX definition
Date: Sat, 15 Jul 2023 02:04:00 +0100 [thread overview]
Message-ID: <20230715010407.1751715-4-fabrizio.castro.jz@renesas.com> (raw)
In-Reply-To: <20230715010407.1751715-1-fabrizio.castro.jz@renesas.com>
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@renesas.com>
---
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
next prev parent reply other threads:[~2023-07-15 1:04 UTC|newest]
Thread overview: 30+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-07-15 1:03 [PATCH 00/10] spi: rzv2m-csi: Code refactoring Fabrizio Castro
2023-07-15 1:03 ` [PATCH 01/10] spi: rzv2m-csi: Add missing include Fabrizio Castro
2023-07-15 1:03 ` [PATCH 02/10] spi: rzv2m-csi: Adopt HZ_PER_MHZ for max spi clock Fabrizio Castro
2023-07-17 9:24 ` Geert Uytterhoeven
2023-07-15 1:04 ` Fabrizio Castro [this message]
2023-07-17 9:27 ` [PATCH 03/10] spi: rzv2m-csi: Rework CSI_CKS_MAX definition Geert Uytterhoeven
2023-07-15 1:04 ` [PATCH 04/10] spi: rzv2m-csi: Leave readl_poll_timeout calls for last Fabrizio Castro
2023-07-17 9:29 ` Geert Uytterhoeven
2023-07-15 1:04 ` [PATCH 05/10] spi: rzv2m-csi: Replace unnecessary ternary operators Fabrizio Castro
2023-07-17 9:30 ` Geert Uytterhoeven
2023-07-15 1:04 ` [PATCH 06/10] spi: rzv2m-csi: Squash timing settings into one statement Fabrizio Castro
2023-07-15 7:54 ` Andy Shevchenko
2023-07-17 10:44 ` Fabrizio Castro
2023-07-17 11:15 ` Andy Shevchenko
2023-07-15 1:04 ` [PATCH 07/10] spi: rzv2m-csi: Switch to using {read,write}s{b,w} Fabrizio Castro
2023-07-17 9:37 ` Geert Uytterhoeven
2023-07-17 10:36 ` Fabrizio Castro
2023-07-17 11:18 ` Andy Shevchenko
2023-07-17 13:00 ` Fabrizio Castro
2023-07-17 16:31 ` Fabrizio Castro
2023-07-15 1:04 ` [PATCH 08/10] spi: rzv2m-csi: Improve data types and alignment Fabrizio Castro
2023-07-17 9:44 ` Geert Uytterhoeven
2023-07-15 1:04 ` [PATCH 09/10] spi: rzv2m-csi: Get rid of the x_trg{_words} tables Fabrizio Castro
2023-07-15 7:57 ` Andy Shevchenko
2023-07-17 9:49 ` Geert Uytterhoeven
2023-07-15 1:04 ` [PATCH 10/10] spi: rzv2m-csi: Make use of device_set_node Fabrizio Castro
2023-07-15 7:58 ` Andy Shevchenko
2023-07-17 15:05 ` Fabrizio Castro
2023-07-15 8:00 ` [PATCH 00/10] spi: rzv2m-csi: Code refactoring Andy Shevchenko
2023-07-18 18:46 ` (subset) " Mark Brown
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