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Commit 97ca0d6c authored by Mark A. Greer's avatar Mark A. Greer Committed by Mark Brown
Browse files

spi: omap2-mcspi: Configure hardware when slave driver changes mode 



Commit id 2bd16e3e
(spi: omap2-mcspi: Do not configure the controller
on each transfer unless needed) does its job too
well so omap2_mcspi_setup_transfer() isn't called
even when an SPI slave driver changes 'spi->mode'.
The result is that the mode requested by the SPI
slave driver never takes effect.

Fix this by adding the 'mode' member to the
omap2_mcspi_cs structure which holds the mode
value that the hardware is configured for.
When the SPI slave driver changes 'spi->mode'
it will be different than the value of this new
member and the SPI master driver will know that
the hardware must be reconfigured (by calling
omap2_mcspi_setup_transfer()).

Fixes: 2bd16e3e (spi: omap2-mcspi: Do not configure the controller on each transfer unless needed)
Signed-off-by: default avatarMark A. Greer <mgreer@animalcreek.com>
Signed-off-by: default avatarMark Brown <broonie@linaro.org>
Cc: stable@vger.kernel.org
parent 7171511e

drivers/spi/spi-omap2-mcspi.c

+14 −0
Original line number Diff line number Diff line
@@ -149,6 +149,7 @@ struct omap2_mcspi_cs { 
	void __iomem		*base;

	unsigned long		phys;

	int			word_len;

	u16			mode;

	struct list_head	node;

	/* Context save and restore shadow register */

	u32			chconf0, chctrl0;
@@ -926,6 +927,8 @@ static int omap2_mcspi_setup_transfer(struct spi_device *spi, 


	mcspi_write_chconf0(spi, l);



	cs->mode = spi->mode;



	dev_dbg(&spi->dev, "setup: speed %d, sample %s edge, clk %s\n",

			speed_hz,

			(spi->mode & SPI_CPHA) ? "trailing" : "leading",
@@ -998,6 +1001,7 @@ static int omap2_mcspi_setup(struct spi_device *spi) 
			return -ENOMEM;

		cs->base = mcspi->base + spi->chip_select * 0x14;

		cs->phys = mcspi->phys + spi->chip_select * 0x14;

		cs->mode = 0;

		cs->chconf0 = 0;

		cs->chctrl0 = 0;

		spi->controller_state = cs;
@@ -1079,6 +1083,16 @@ static void omap2_mcspi_work(struct omap2_mcspi *mcspi, struct spi_message *m) 
	cs = spi->controller_state;

	cd = spi->controller_data;



	/*

	 * The slave driver could have changed spi->mode in which case

	 * it will be different from cs->mode (the current hardware setup).

	 * If so, set par_override (even though its not a parity issue) so

	 * omap2_mcspi_setup_transfer will be called to configure the hardware

	 * with the correct mode on the first iteration of the loop below.

	 */

	if (spi->mode != cs->mode)

		par_override = 1;



	omap2_mcspi_set_enable(spi, 0);

	list_for_each_entry(t, &m->transfers, transfer_list) {

		if (t->tx_buf == NULL && t->rx_buf == NULL && t->len) {