Revert "spi: spi-bcm2835: Re-enable HW CS"

This reverts commit 49b9bd8.

See: #3687

drivers/spi/spi-bcm2835.c

@@ -1173,57 +1173,9 @@ static void bcm2835_spi_handle_err(struct spi_controller *ctlr,
 	bcm2835_spi_reset_hw(ctlr);
 }
 
-static void bcm2835_spi_set_cs(struct spi_device *spi, bool gpio_level)
+static int chip_match_name(struct gpio_chip *chip, void *data)
 {
-	/*
-	 * we can assume that we are "native" as per spi_set_cs
-	 *   calling us ONLY when cs_gpio is not set
-	 * we can also assume that we are CS < 3 as per bcm2835_spi_setup
-	 *   we would not get called because of error handling there.
-	 * the level passed is the electrical level not enabled/disabled
-	 *   so it has to get translated back to enable/disable
-	 *   see spi_set_cs in spi.c for the implementation
-	 */
-
-	struct spi_master *master = spi->master;
-	struct bcm2835_spi *bs = spi_master_get_devdata(master);
-	u32 cs = bcm2835_rd(bs, BCM2835_SPI_CS);
-	bool enable;
-
-	/* calculate the enable flag from the passed gpio_level */
-	enable = (spi->mode & SPI_CS_HIGH) ? gpio_level : !gpio_level;
-
-	/* set flags for "reverse" polarity in the registers */
-	if (spi->mode & SPI_CS_HIGH) {
-		/* set the correct CS-bits */
-		cs |= BCM2835_SPI_CS_CSPOL;
-		cs |= BCM2835_SPI_CS_CSPOL0 << spi->chip_select;
-	} else {
-		/* clean the CS-bits */
-		cs &= ~BCM2835_SPI_CS_CSPOL;
-		cs &= ~(BCM2835_SPI_CS_CSPOL0 << spi->chip_select);
-	}
-
-	/* select the correct chip_select depending on disabled/enabled */
-	if (enable) {
-		/* set cs correctly */
-		if (spi->mode & SPI_NO_CS) {
-			/* use the "undefined" chip-select */
-			cs |= BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01;
-		} else {
-			/* set the chip select */
-			cs &= ~(BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01);
-			cs |= spi->chip_select;
-		}
-	} else {
-		/* disable CSPOL which puts HW-CS into deselected state */
-		cs &= ~BCM2835_SPI_CS_CSPOL;
-		/* use the "undefined" chip-select as precaution */
-		cs |= BCM2835_SPI_CS_CS_10 | BCM2835_SPI_CS_CS_01;
-	}
-
-	/* finally set the calculated flags in SPI_CS */
-	bcm2835_wr(bs, BCM2835_SPI_CS, cs);
+	return !strcmp(chip->label, data);
 }
 
 static int bcm2835_spi_setup(struct spi_device *spi)
@@ -1341,7 +1293,6 @@ static int bcm2835_spi_probe(struct platform_device *pdev)
 	ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
 	ctlr->num_chipselect = BCM2835_SPI_NUM_CS;
 	ctlr->setup = bcm2835_spi_setup;
-	ctlr->set_cs = bcm2835_spi_set_cs;
 	ctlr->transfer_one = bcm2835_spi_transfer_one;
 	ctlr->handle_err = bcm2835_spi_handle_err;
 	ctlr->prepare_message = bcm2835_spi_prepare_message;