The patch
spi: mediatek: adjust register to enhance time accuracy
has been applied to the spi tree at
git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git
All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying
to this mail.
Thanks,
Mark
>From 058fe49da3b6ab71b57effd49dcc5d007071eea5 Mon Sep 17 00:00:00 2001
From: Leilk Liu <leilk.liu@xxxxxxxxxxxx>
Date: Mon, 12 Jun 2017 09:24:39 +0800
Subject: [PATCH] spi: mediatek: adjust register to enhance time accuracy
this patch adjust register to enhance time accuracy.
Signed-off-by: Leilk Liu <leilk.liu@xxxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-mt65xx.c | 45 ++++++++++++++++++++++++++++----
include/linux/platform_data/spi-mt65xx.h | 2 ++
2 files changed, 42 insertions(+), 5 deletions(-)
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
index 278867a31950..eae73b58248b 100644
--- a/drivers/spi/spi-mt65xx.c
+++ b/drivers/spi/spi-mt65xx.c
@@ -35,11 +35,15 @@
#define SPI_CMD_REG 0x0018
#define SPI_STATUS0_REG 0x001c
#define SPI_PAD_SEL_REG 0x0024
+#define SPI_CFG2_REG 0x0028
#define SPI_CFG0_SCK_HIGH_OFFSET 0
#define SPI_CFG0_SCK_LOW_OFFSET 8
#define SPI_CFG0_CS_HOLD_OFFSET 16
#define SPI_CFG0_CS_SETUP_OFFSET 24
+#define SPI_ADJUST_CFG0_SCK_LOW_OFFSET 16
+#define SPI_ADJUST_CFG0_CS_HOLD_OFFSET 0
+#define SPI_ADJUST_CFG0_CS_SETUP_OFFSET 16
#define SPI_CFG1_CS_IDLE_OFFSET 0
#define SPI_CFG1_PACKET_LOOP_OFFSET 8
@@ -55,6 +59,8 @@
#define SPI_CMD_RST BIT(2)
#define SPI_CMD_PAUSE_EN BIT(4)
#define SPI_CMD_DEASSERT BIT(5)
+#define SPI_CMD_SAMPLE_SEL BIT(6)
+#define SPI_CMD_CS_POL BIT(7)
#define SPI_CMD_CPHA BIT(8)
#define SPI_CMD_CPOL BIT(9)
#define SPI_CMD_RX_DMA BIT(10)
@@ -80,6 +86,8 @@ struct mtk_spi_compatible {
bool need_pad_sel;
/* Must explicitly send dummy Tx bytes to do Rx only transfer */
bool must_tx;
+ /* some IC design adjust cfg register to enhance time accuracy */
+ bool enhance_timing;
};
struct mtk_spi {
@@ -108,6 +116,8 @@ static const struct mtk_spi_compatible mt8173_compat = {
static const struct mtk_chip_config mtk_default_chip_info = {
.rx_mlsb = 1,
.tx_mlsb = 1,
+ .cs_pol = 0,
+ .sample_sel = 0,
};
static const struct of_device_id mtk_spi_of_match[] = {
@@ -182,6 +192,17 @@ static int mtk_spi_prepare_message(struct spi_master *master,
reg_val |= SPI_CMD_RX_ENDIAN;
#endif
+ if (mdata->dev_comp->enhance_timing) {
+ if (chip_config->cs_pol)
+ reg_val |= SPI_CMD_CS_POL;
+ else
+ reg_val &= ~SPI_CMD_CS_POL;
+ if (chip_config->sample_sel)
+ reg_val |= SPI_CMD_SAMPLE_SEL;
+ else
+ reg_val &= ~SPI_CMD_SAMPLE_SEL;
+ }
+
/* set finish and pause interrupt always enable */
reg_val |= SPI_CMD_FINISH_IE | SPI_CMD_PAUSE_IE;
@@ -233,11 +254,25 @@ static void mtk_spi_prepare_transfer(struct spi_master *master,
sck_time = (div + 1) / 2;
cs_time = sck_time * 2;
- reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_HIGH_OFFSET);
- reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
- reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
- reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_SETUP_OFFSET);
- writel(reg_val, mdata->base + SPI_CFG0_REG);
+ if (mdata->dev_comp->enhance_timing) {
+ reg_val |= (((sck_time - 1) & 0xffff)
+ << SPI_CFG0_SCK_HIGH_OFFSET);
+ reg_val |= (((sck_time - 1) & 0xffff)
+ << SPI_ADJUST_CFG0_SCK_LOW_OFFSET);
+ writel(reg_val, mdata->base + SPI_CFG2_REG);
+ reg_val |= (((cs_time - 1) & 0xffff)
+ << SPI_ADJUST_CFG0_CS_HOLD_OFFSET);
+ reg_val |= (((cs_time - 1) & 0xffff)
+ << SPI_ADJUST_CFG0_CS_SETUP_OFFSET);
+ writel(reg_val, mdata->base + SPI_CFG0_REG);
+ } else {
+ reg_val |= (((sck_time - 1) & 0xff)
+ << SPI_CFG0_SCK_HIGH_OFFSET);
+ reg_val |= (((sck_time - 1) & 0xff) << SPI_CFG0_SCK_LOW_OFFSET);
+ reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_HOLD_OFFSET);
+ reg_val |= (((cs_time - 1) & 0xff) << SPI_CFG0_CS_SETUP_OFFSET);
+ writel(reg_val, mdata->base + SPI_CFG0_REG);
+ }
reg_val = readl(mdata->base + SPI_CFG1_REG);
reg_val &= ~SPI_CFG1_CS_IDLE_MASK;
diff --git a/include/linux/platform_data/spi-mt65xx.h b/include/linux/platform_data/spi-mt65xx.h
index 54b04483976c..ba4e4bb70262 100644
--- a/include/linux/platform_data/spi-mt65xx.h
+++ b/include/linux/platform_data/spi-mt65xx.h
@@ -16,5 +16,7 @@
struct mtk_chip_config {
u32 tx_mlsb;
u32 rx_mlsb;
+ u32 cs_pol;
+ u32 sample_sel;
};
#endif
--
2.11.0
--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
