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[PATCH v2] spi: Setup the master controller driver before setting the chipselect

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SPI controllers may need to be properly setup before chip selects
can be used. Therefore, wait until the spi controller has a chance
to perform their setup procedure before trying to use the chip
select.

This also insures that the chip selects pins are in a good
state before asseting them which otherwise may cause confusion.

Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
---
Keystone 2 devices currently fail to boot in linux-next after the
below commit was applied:

spi: bitbang: switch to the generic implementation of transfer_one_message
commit: 0037686596832572bbca05ab168d9884d7d704c1

This patch allows Keystone 2 devices to boot again in linux-next.

Tested this patch on K2E evm and am437 starterkit which both have SPI
devices to insure regressions aren't seen.

V2 Changes:
Update commit message.

 drivers/spi/spi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 4c638f3..9d5525a 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -2059,11 +2059,11 @@ int spi_setup(struct spi_device *spi)
 	if (!spi->max_speed_hz)
 		spi->max_speed_hz = spi->master->max_speed_hz;
 
-	spi_set_cs(spi, false);
-
 	if (spi->master->setup)
 		status = spi->master->setup(spi);
 
+	spi_set_cs(spi, false);
+
 	dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n",
 			(int) (spi->mode & (SPI_CPOL | SPI_CPHA)),
 			(spi->mode & SPI_CS_HIGH) ? "cs_high, " : "",
-- 
2.6.1

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[PATCH v2] spi: Setup the master controller driver before setting the chipselect Franklin S Cooper Jr <fcooper@ti.com> - 2015-10-16 17:30 +0200
  Re: [PATCH v2] spi: Setup the master controller driver before setting  the chipselect Andy Shevchenko <andy.shevchenko@gmail.com> - 2015-10-16 17:50 +0200
    Re: [PATCH v2] spi: Setup the master controller driver before setting  the chipselect "Franklin S Cooper Jr." <fcooper@ti.com> - 2015-10-16 17:50 +0200
      Re: [PATCH v2] spi: Setup the master controller driver before setting  the chipselect Andy Shevchenko <andy.shevchenko@gmail.com> - 2015-10-16 18:00 +0200

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