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71 lines
2.1 KiB
71 lines
2.1 KiB
7 years ago
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From dd7aa8d4b53b3484ba31ba56f3ff1be7deb38530 Mon Sep 17 00:00:00 2001
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From: Maxime Chevallier <maxime.chevallier@smile.fr>
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Date: Tue, 10 Oct 2017 10:43:18 +0200
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Subject: spi: a3700: Change SPI mode before asserting chip-select
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The spi device mode should be configured in the controller before the
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chip-select is asserted, so that a clock polarity configuration change
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is not interpreted as a clock tick by the device.
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This patch moves the mode setting to the 'prepare_message' function
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instead of the 'transfer_one' function.
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By doing so, this patch also removes redundant code in
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a3700_spi_clock_set.
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This was tested on EspressoBin board, with spidev.
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Signed-off-by: Maxime Chevallier <maxime.chevallier@smile.fr>
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Signed-off-by: Mark Brown <broonie@kernel.org>
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---
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drivers/spi/spi-armada-3700.c | 17 ++++-------------
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1 file changed, 4 insertions(+), 13 deletions(-)
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--- a/drivers/spi/spi-armada-3700.c
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+++ b/drivers/spi/spi-armada-3700.c
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@@ -214,7 +214,7 @@ static void a3700_spi_mode_set(struct a3
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}
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static void a3700_spi_clock_set(struct a3700_spi *a3700_spi,
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- unsigned int speed_hz, u16 mode)
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+ unsigned int speed_hz)
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{
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u32 val;
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u32 prescale;
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@@ -239,17 +239,6 @@ static void a3700_spi_clock_set(struct a
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val |= A3700_SPI_CLK_CAPT_EDGE;
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spireg_write(a3700_spi, A3700_SPI_IF_TIME_REG, val);
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}
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-
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- val = spireg_read(a3700_spi, A3700_SPI_IF_CFG_REG);
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- val &= ~(A3700_SPI_CLK_POL | A3700_SPI_CLK_PHA);
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-
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- if (mode & SPI_CPOL)
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- val |= A3700_SPI_CLK_POL;
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-
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- if (mode & SPI_CPHA)
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- val |= A3700_SPI_CLK_PHA;
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-
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- spireg_write(a3700_spi, A3700_SPI_IF_CFG_REG, val);
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}
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static void a3700_spi_bytelen_set(struct a3700_spi *a3700_spi, unsigned int len)
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@@ -431,7 +420,7 @@ static void a3700_spi_transfer_setup(str
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a3700_spi = spi_master_get_devdata(spi->master);
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- a3700_spi_clock_set(a3700_spi, xfer->speed_hz, spi->mode);
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+ a3700_spi_clock_set(a3700_spi, xfer->speed_hz);
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byte_len = xfer->bits_per_word >> 3;
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@@ -592,6 +581,8 @@ static int a3700_spi_prepare_message(str
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a3700_spi_bytelen_set(a3700_spi, 4);
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+ a3700_spi_mode_set(a3700_spi, spi->mode);
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+
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return 0;
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}
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