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

This reverts commit 49b9bd89784e3fa29f143ebf1ac8f125be47b708.

See: https://github.com/raspberrypi/linux/pull/3687

diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index 9dccfba..6899558 100644 (file)
--- a/drivers/spi/spi-bcm2835.c
+++ b/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;