Merge tag 'spi-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi updates from Mark Brown:
 "A fairly quiet release for the SPI subsystem, the standout changes
  being:

   - Core support for implementing bits per word constraints implemented
     by Stephen Warren, factoring some code out of drivers.

   - Addition of polling mode support for the s3c64xx driver as some
     newer Exynos systems have taken the unusual step of removing
     interrupt support.

   - Use of the in-IP FIFO and generic dmaengine support for the OMAP2
     driver, providing improved performance.

   - Conversion of the mpc512x driver to use the core message queue
     infrastructure.

  The nicest thing being that all the factoring out into common code
  leads to a negative diffstat overall."

* tag 'spi-v3.11' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (42 commits)
  spi/s3c64xx: Rely on the compiler eliminating the OF ID table
  spi: s3c64xx: Added support for exynos5440 spi
  spi: s3c64xx: Added provision for dedicated cs pin
  spi: omap2-mcspi: add generic DMA request support to the DT binding
  spi: omap2-mcspi: convert to dma_request_slave_channel_compat()
  spi/s3c64xx: Make wait_for_timeout() function name less generic
  spi: s3c64xx: added support for polling mode
  spi: omap2-mcspi: Add FIFO buffer support
  spi: omap2-mcspi: Move bytes per word calculation to the function
  spi: spi-xilinx: cleanup a check in xilinx_spi_txrx_bufs()
  spi: spi-nuc900: Remove redundant platform_set_drvdata()
  spi: spi-fsl-lib: Make mpc8xxx_spi_work static
  spi: spi-topcliff-pch: Fix sparse warnings
  spi: spi-xilinx: Remove redundant platform_set_drvdata()
  spi: spi-xilinx: Add run run-time endian detection
  spi: mpc512x: use the SPI subsystem's message queue
  spi: mpc512x: improve throughput in the RX/TX func
  spi: mpc512x: minor prep before feature change
  spi: atmel: convert to dma_request_slave_channel_compat()
  spi: sirf: avoid uninitialized-use warning
  ...

1 files changed, 22 insertions, 26 deletions

diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index 34d18dcfa0d..fb56fcfdf65 100644
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -30,6 +30,7 @@
  */
 #define XSPI_CR_OFFSET		0x60	/* Control Register */
 
+#define XSPI_CR_LOOP		0x01
 #define XSPI_CR_ENABLE		0x02
 #define XSPI_CR_MASTER_MODE	0x04
 #define XSPI_CR_CPOL		0x08
@@ -232,21 +233,6 @@ static int xilinx_spi_setup_transfer(struct spi_device *spi,
 	return 0;
 }
 
-static int xilinx_spi_setup(struct spi_device *spi)
-{
-	/* always return 0, we can not check the number of bits.
-	 * There are cases when SPI setup is called before any driver is
-	 * there, in that case the SPI core defaults to 8 bits, which we
-	 * do not support in some cases. But if we return an error, the
-	 * SPI device would not be registered and no driver can get hold of it
-	 * When the driver is there, it will call SPI setup again with the
-	 * correct number of bits per transfer.
-	 * If a driver setups with the wrong bit number, it will fail when
-	 * it tries to do a transfer
-	 */
-	return 0;
-}
-
 static void xilinx_spi_fill_tx_fifo(struct xilinx_spi *xspi)
 {
 	u8 sr;
@@ -315,7 +301,7 @@ static int xilinx_spi_txrx_bufs(struct spi_device *spi, struct spi_transfer *t)
 		}
 
 		/* See if there is more data to send */
-		if (!xspi->remaining_bytes > 0)
+		if (xspi->remaining_bytes <= 0)
 			break;
 	}
 
@@ -355,11 +341,12 @@ static const struct of_device_id xilinx_spi_of_match[] = {
 MODULE_DEVICE_TABLE(of, xilinx_spi_of_match);
 
 struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem,
-	u32 irq, s16 bus_num, int num_cs, int little_endian, int bits_per_word)
+	u32 irq, s16 bus_num, int num_cs, int bits_per_word)
 {
 	struct spi_master *master;
 	struct xilinx_spi *xspi;
 	int ret;
+	u32 tmp;
 
 	master = spi_alloc_master(dev, sizeof(struct xilinx_spi));
 	if (!master)
@@ -373,7 +360,6 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem,
 	xspi->bitbang.chipselect = xilinx_spi_chipselect;
 	xspi->bitbang.setup_transfer = xilinx_spi_setup_transfer;
 	xspi->bitbang.txrx_bufs = xilinx_spi_txrx_bufs;
-	xspi->bitbang.master->setup = xilinx_spi_setup;
 	init_completion(&xspi->done);
 
 	if (!request_mem_region(mem->start, resource_size(mem),
@@ -392,13 +378,25 @@ struct spi_master *xilinx_spi_init(struct device *dev, struct resource *mem,
 
 	xspi->mem = *mem;
 	xspi->irq = irq;
-	if (little_endian) {
-		xspi->read_fn = xspi_read32;
-		xspi->write_fn = xspi_write32;
-	} else {
+
+	/*
+	 * Detect endianess on the IP via loop bit in CR. Detection
+	 * must be done before reset is sent because incorrect reset
+	 * value generates error interrupt.
+	 * Setup little endian helper functions first and try to use them
+	 * and check if bit was correctly setup or not.
+	 */
+	xspi->read_fn = xspi_read32;
+	xspi->write_fn = xspi_write32;
+
+	xspi->write_fn(XSPI_CR_LOOP, xspi->regs + XSPI_CR_OFFSET);
+	tmp = xspi->read_fn(xspi->regs + XSPI_CR_OFFSET);
+	tmp &= XSPI_CR_LOOP;
+	if (tmp != XSPI_CR_LOOP) {
 		xspi->read_fn = xspi_read32_be;
 		xspi->write_fn = xspi_write32_be;
 	}
+
 	xspi->bits_per_word = bits_per_word;
 	if (xspi->bits_per_word == 8) {
 		xspi->tx_fn = xspi_tx8;
@@ -462,14 +460,13 @@ static int xilinx_spi_probe(struct platform_device *dev)
 {
 	struct xspi_platform_data *pdata;
 	struct resource *r;
-	int irq, num_cs = 0, little_endian = 0, bits_per_word = 8;
+	int irq, num_cs = 0, bits_per_word = 8;
 	struct spi_master *master;
 	u8 i;
 
 	pdata = dev->dev.platform_data;
 	if (pdata) {
 		num_cs = pdata->num_chipselect;
-		little_endian = pdata->little_endian;
 		bits_per_word = pdata->bits_per_word;
 	}
 
@@ -501,7 +498,7 @@ static int xilinx_spi_probe(struct platform_device *dev)
 		return -ENXIO;
 
 	master = xilinx_spi_init(&dev->dev, r, irq, dev->id, num_cs,
-				 little_endian, bits_per_word);
+				 bits_per_word);
 	if (!master)
 		return -ENODEV;
 
@@ -517,7 +514,6 @@ static int xilinx_spi_probe(struct platform_device *dev)
 static int xilinx_spi_remove(struct platform_device *dev)
 {
 	xilinx_spi_deinit(platform_get_drvdata(dev));
-	platform_set_drvdata(dev, 0);
 
 	return 0;
 }