forked from luck/tmp_suning_uos_patched
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:
5d7e2b5ed5
spi: core: allow reporting the effectivly used speed_hz for a transfer
regards,
Marc
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commit
e752ec8e92
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@ -1082,7 +1082,7 @@ static int bcm2835_spi_transfer_one(struct spi_controller *ctlr,
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struct spi_transfer *tfr)
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{
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struct bcm2835_spi *bs = spi_controller_get_devdata(ctlr);
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unsigned long spi_hz, clk_hz, cdiv, spi_used_hz;
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unsigned long spi_hz, clk_hz, cdiv;
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unsigned long hz_per_byte, byte_limit;
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u32 cs = bs->prepare_cs[spi->chip_select];
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@ -1102,7 +1102,7 @@ static int bcm2835_spi_transfer_one(struct spi_controller *ctlr,
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} else {
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cdiv = 0; /* 0 is the slowest we can go */
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}
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spi_used_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);
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tfr->effective_speed_hz = cdiv ? (clk_hz / cdiv) : (clk_hz / 65536);
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bcm2835_wr(bs, BCM2835_SPI_CLK, cdiv);
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/* handle all the 3-wire mode */
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@ -1122,7 +1122,7 @@ static int bcm2835_spi_transfer_one(struct spi_controller *ctlr,
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* per 300,000 Hz of bus clock.
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*/
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hz_per_byte = polling_limit_us ? (9 * 1000000) / polling_limit_us : 0;
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byte_limit = hz_per_byte ? spi_used_hz / hz_per_byte : 1;
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byte_limit = hz_per_byte ? tfr->effective_speed_hz / hz_per_byte : 1;
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/* run in polling mode for short transfers */
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if (tfr->len < byte_limit)
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@ -345,7 +345,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master,
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struct spi_transfer *tfr)
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{
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struct bcm2835aux_spi *bs = spi_master_get_devdata(master);
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unsigned long spi_hz, clk_hz, speed, spi_used_hz;
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unsigned long spi_hz, clk_hz, speed;
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unsigned long hz_per_byte, byte_limit;
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/* calculate the registers to handle
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@ -374,7 +374,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master,
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/* set the new speed */
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bs->cntl[0] |= speed << BCM2835_AUX_SPI_CNTL0_SPEED_SHIFT;
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spi_used_hz = clk_hz / (2 * (speed + 1));
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tfr->effective_speed_hz = clk_hz / (2 * (speed + 1));
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/* set transmit buffers and length */
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bs->tx_buf = tfr->tx_buf;
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@ -391,7 +391,7 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master,
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* 30 µs per 300,000 Hz of bus clock.
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*/
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hz_per_byte = polling_limit_us ? (9 * 1000000) / polling_limit_us : 0;
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byte_limit = hz_per_byte ? spi_used_hz / hz_per_byte : 1;
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byte_limit = hz_per_byte ? tfr->effective_speed_hz / hz_per_byte : 1;
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/* run in polling mode for short transfers */
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if (tfr->len < byte_limit)
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