Unverified Commit e752ec8e authored by Mark Brown's avatar Mark Brown
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Merge series "spi: bcm2835/bcm2835aux: support effective_speed_hz" from Marc... 

Merge series "spi: bcm2835/bcm2835aux: support effective_speed_hz" from Marc Kleine-Budde <mkl@pengutronix.de>:

Hello,

I've picked up and forward ported Martin Sperl's patches which add support for
effective_speed_hz to the SPI controllers found on all raspberry pi models.

See the following patch, which adds this feature to the SPI core, for more
information:

    5d7e2b5e spi: core: allow reporting the effectivly used speed_hz for a transfer

regards,
Marc

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parents 499de01c 5e94c3cd

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)

drivers/spi/spi-bcm2835aux.c

+3 −3
Original line number Diff line number Diff line
@@ -345,7 +345,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master, 
				       struct spi_transfer *tfr)

{

	struct bcm2835aux_spi *bs = spi_master_get_devdata(master);

	unsigned long spi_hz, clk_hz, speed, spi_used_hz;

	unsigned long spi_hz, clk_hz, speed;

	unsigned long hz_per_byte, byte_limit;



	/* calculate the registers to handle
@@ -374,7 +374,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master, 
	/* set the new speed */

	bs->cntl[0] |= speed << BCM2835_AUX_SPI_CNTL0_SPEED_SHIFT;



	spi_used_hz = clk_hz / (2 * (speed + 1));

	tfr->effective_speed_hz = clk_hz / (2 * (speed + 1));



	/* set transmit buffers and length */

	bs->tx_buf = tfr->tx_buf;
@@ -391,7 +391,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master, 
	 * 30 µs 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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