target/linux/pistachio/patches-4.9/104-spi-img-spfi-use-device-0-configuration-for-all-devi.patch

   1 From 905ee06a9966113fe51d6bad1819759cb30fd0bd Mon Sep 17 00:00:00 2001
   2 From: Ionela Voinescu <ionela.voinescu@imgtec.com>
   3 Date: Tue, 9 Feb 2016 10:18:31 +0000
   4 Subject: spi: img-spfi: use device 0 configuration for all devices
   5
   6 Given that we control the chip select line externally
   7 we can use only one parameter register (device 0 parameter
   8 register) and one set of configuration bits (port configuration
   9 bits for device 0) for all devices (all chip select lines).
  10
  11 Signed-off-by: Ionela Voinescu <ionela.voinescu@imgtec.com>
  12 ---
  13  drivers/spi/spi-img-spfi.c | 23 ++++++++++++++++-------
  14  1 file changed, 16 insertions(+), 7 deletions(-)
  15
  16 diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c
  17 index 0d73d31..231b59c 100644
  18 --- a/drivers/spi/spi-img-spfi.c
  19 +++ b/drivers/spi/spi-img-spfi.c
  20 @@ -437,18 +437,23 @@ static int img_spfi_prepare(struct spi_master *master, struct spi_message *msg)
  21         struct img_spfi *spfi = spi_master_get_devdata(master);
  22         u32 val;
  23
  24 +       /*
  25 +        * The chip select line is controlled externally so
  26 +        * we can use the CS0 configuration for all devices
  27 +        */
  28         val = spfi_readl(spfi, SPFI_PORT_STATE);
  29 +
  30 +       /* 0 for device selection */
  31         val &= ~(SPFI_PORT_STATE_DEV_SEL_MASK <<
  32                  SPFI_PORT_STATE_DEV_SEL_SHIFT);
  33 -       val |= msg->spi->chip_select << SPFI_PORT_STATE_DEV_SEL_SHIFT;
  34         if (msg->spi->mode & SPI_CPHA)
  35 -               val |= SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select);
  36 +               val |= SPFI_PORT_STATE_CK_PHASE(0);
  37         else
  38 -               val &= ~SPFI_PORT_STATE_CK_PHASE(msg->spi->chip_select);
  39 +               val &= ~SPFI_PORT_STATE_CK_PHASE(0);
  40         if (msg->spi->mode & SPI_CPOL)
  41 -               val |= SPFI_PORT_STATE_CK_POL(msg->spi->chip_select);
  42 +               val |= SPFI_PORT_STATE_CK_POL(0);
  43         else
  44 -               val &= ~SPFI_PORT_STATE_CK_POL(msg->spi->chip_select);
  45 +               val &= ~SPFI_PORT_STATE_CK_POL(0);
  46         spfi_writel(spfi, val, SPFI_PORT_STATE);
  47
  48         return 0;
  49 @@ -548,11 +553,15 @@ static void img_spfi_config(struct spi_master *master, struct spi_device *spi,
  50         div = DIV_ROUND_UP(clk_get_rate(spfi->spfi_clk), xfer->speed_hz);
  51         div = clamp(512 / (1 << get_count_order(div)), 1, 128);
  52
  53 -       val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(spi->chip_select));
  54 +       /*
  55 +        * The chip select line is controlled externally so
  56 +        * we can use the CS0 parameters for all devices
  57 +        */
  58 +       val = spfi_readl(spfi, SPFI_DEVICE_PARAMETER(0));
  59         val &= ~(SPFI_DEVICE_PARAMETER_BITCLK_MASK <<
  60                  SPFI_DEVICE_PARAMETER_BITCLK_SHIFT);
  61         val |= div << SPFI_DEVICE_PARAMETER_BITCLK_SHIFT;
  62 -       spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(spi->chip_select));
  63 +       spfi_writel(spfi, val, SPFI_DEVICE_PARAMETER(0));
  64
  65         if (!list_is_last(&xfer->transfer_list, &master->cur_msg->transfers) &&
  66                 /*
  67 --
  68 2.7.4
  69