Unverified Commit 9df2003d authored by Martin Sperl's avatar Martin Sperl Committed by Mark Brown
Browse files

spi: bcm2835: support effective_speed_hz 



Setting spi_transfer->effective_speed_hz in transfer_one so that
it can get used in cs_change_delay configured with delay as a muliple
of SPI clock cycles.

Signed-off-by: default avatarMartin Sperl <kernel@martin.sperl.org>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Link: https://lore.kernel.org/r/20200709074120.110069-2-mkl@pengutronix.de


Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent badfae42

drivers/spi/spi-bcm2835.c

+3 −3
Original line number Diff line number Diff line
@@ -1082,7 +1082,7 @@ static int bcm2835_spi_transfer_one(struct spi_controller *ctlr, 
				    struct spi_transfer *tfr)

{

	struct bcm2835_spi *bs = spi_controller_get_devdata(ctlr);

	unsigned long spi_hz, clk_hz, cdiv, spi_used_hz;

	unsigned long spi_hz, clk_hz, cdiv;

	unsigned long hz_per_byte, byte_limit;

	u32 cs = bs->prepare_cs[spi->chip_select];
@@ -1102,7 +1102,7 @@ static int bcm2835_spi_transfer_one(struct spi_controller *ctlr, 
	} else {

		cdiv = 0; /* 0 is the slowest we can go */

	}

	spi_used_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);

	tfr->effective_speed_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);

	bcm2835_wr(bs, BCM2835_SPI_CLK, cdiv);



	/* handle all the 3-wire mode */
@@ -1122,7 +1122,7 @@ static int bcm2835_spi_transfer_one(struct spi_controller *ctlr, 
	 * per 300,000 Hz of bus clock.

	 */

	hz_per_byte = polling_limit_us ? (9 * 1000000) / polling_limit_us : 0;

	byte_limit = hz_per_byte ? spi_used_hz / hz_per_byte : 1;

	byte_limit = hz_per_byte ? tfr->effective_speed_hz / hz_per_byte : 1;



	/* run in polling mode for short transfers */

	if (tfr->len < byte_limit)

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