target/linux/ar71xx/patches-3.2/207-spi-ath79-make-chipselect-logic-more-flexible.patch

   1 From b875f877d06acb852342636db4c3d1e6c9fe01ba Mon Sep 17 00:00:00 2001
   2 From: Gabor Juhos <juhosg@openwrt.org>
   3 Date: Wed, 11 Jan 2012 22:25:11 +0100
   4 Subject: [PATCH 7/7] spi/ath79: make chipselect logic more flexible
   5
   6 Signed-off-by: Gabor Juhos <juhosg@openwrt.org>
   7 ---
   8  .../include/asm/mach-ath79/ath79_spi_platform.h    |    8 ++-
   9  drivers/spi/spi-ath79.c                            |   65 +++++++++++--------
  10  2 files changed, 45 insertions(+), 28 deletions(-)
  11
  12 --- a/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h
  13 +++ b/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h
  14 @@ -16,8 +16,14 @@ struct ath79_spi_platform_data {
  15         unsigned        num_chipselect;
  16  };
  17
  18 +enum ath79_spi_cs_type {
  19 +       ATH79_SPI_CS_TYPE_INTERNAL,
  20 +       ATH79_SPI_CS_TYPE_GPIO,
  21 +};
  22 +
  23  struct ath79_spi_controller_data {
  24 -       unsigned        gpio;
  25 +       enum ath79_spi_cs_type cs_type;
  26 +       unsigned cs_line;
  27  };
  28
  29  #endif /* _ATH79_SPI_PLATFORM_H */
  30 --- a/drivers/spi/spi-ath79.c
  31 +++ b/drivers/spi/spi-ath79.c
  32 @@ -30,6 +30,8 @@
  33
  34  #define DRV_NAME       "ath79-spi"
  35
  36 +#define ATH79_SPI_CS_LINE_MAX  2
  37 +
  38  struct ath79_spi {
  39         struct spi_bitbang      bitbang;
  40         u32                     ioc_base;
  41 @@ -62,6 +64,7 @@ static void ath79_spi_chipselect(struct
  42  {
  43         struct ath79_spi *sp = ath79_spidev_to_sp(spi);
  44         int cs_high = (spi->mode & SPI_CS_HIGH) ? is_active : !is_active;
  45 +       struct ath79_spi_controller_data *cdata = spi->controller_data;
  46
  47         if (is_active) {
  48                 /* set initial clock polarity */
  49 @@ -73,20 +76,21 @@ static void ath79_spi_chipselect(struct
  50                 ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
  51         }
  52
  53 -       if (spi->chip_select) {
  54 -               struct ath79_spi_controller_data *cdata = spi->controller_data;
  55 -
  56 -               /* SPI is normally active-low */
  57 -               gpio_set_value(cdata->gpio, cs_high);
  58 -       } else {
  59 +       switch (cdata->cs_type) {
  60 +       case ATH79_SPI_CS_TYPE_INTERNAL:
  61                 if (cs_high)
  62 -                       sp->ioc_base |= AR71XX_SPI_IOC_CS0;
  63 +                       sp->ioc_base |= AR71XX_SPI_IOC_CS(cdata->cs_line);
  64                 else
  65 -                       sp->ioc_base &= ~AR71XX_SPI_IOC_CS0;
  66 +                       sp->ioc_base &= ~AR71XX_SPI_IOC_CS(cdata->cs_line);
  67
  68                 ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base);
  69 -       }
  70 +               break;
  71
  72 +       case ATH79_SPI_CS_TYPE_GPIO:
  73 +               /* SPI is normally active-low */
  74 +               gpio_set_value(cdata->cs_line, cs_high);
  75 +               break;
  76 +       }
  77  }
  78
  79  static void ath79_spi_enable(struct ath79_spi *sp)
  80 @@ -113,24 +117,30 @@ static void ath79_spi_disable(struct ath
  81  static int ath79_spi_setup_cs(struct spi_device *spi)
  82  {
  83         struct ath79_spi_controller_data *cdata;
  84 +       unsigned long flags;
  85         int status;
  86
  87         cdata = spi->controller_data;
  88 -       if (spi->chip_select && !cdata)
  89 +       if (!cdata)
  90                 return -EINVAL;
  91
  92         status = 0;
  93 -       if (spi->chip_select) {
  94 -               unsigned long flags;
  95 +       switch (cdata->cs_type) {
  96 +       case ATH79_SPI_CS_TYPE_INTERNAL:
  97 +               if (cdata->cs_line > ATH79_SPI_CS_LINE_MAX)
  98 +                       status = -EINVAL;
  99 +               break;
 100
 101 +       case ATH79_SPI_CS_TYPE_GPIO:
 102                 flags = GPIOF_DIR_OUT;
 103                 if (spi->mode & SPI_CS_HIGH)
 104                         flags |= GPIOF_INIT_HIGH;
 105                 else
 106                         flags |= GPIOF_INIT_LOW;
 107
 108 -               status = gpio_request_one(cdata->gpio, flags,
 109 +               status = gpio_request_one(cdata->cs_line, flags,
 110                                           dev_name(&spi->dev));
 111 +               break;
 112         }
 113
 114         return status;
 115 @@ -138,9 +148,15 @@ static int ath79_spi_setup_cs(struct spi
 116
 117  static void ath79_spi_cleanup_cs(struct spi_device *spi)
 118  {
 119 -       if (spi->chip_select) {
 120 -               struct ath79_spi_controller_data *cdata = spi->controller_data;
 121 -               gpio_free(cdata->gpio);
 122 +       struct ath79_spi_controller_data *cdata = spi->controller_data;
 123 +
 124 +       switch (cdata->cs_type) {
 125 +       case ATH79_SPI_CS_TYPE_INTERNAL:
 126 +               /* nothing to do */
 127 +               break;
 128 +       case ATH79_SPI_CS_TYPE_GPIO:
 129 +               gpio_free(cdata->cs_line);
 130 +               break;
 131         }
 132  }
 133
 134 @@ -206,6 +222,10 @@ static __devinit int ath79_spi_probe(str
 135         struct resource *r;
 136         int ret;
 137
 138 +       pdata = pdev->dev.platform_data;
 139 +       if (!pdata)
 140 +               return -EINVAL;
 141 +
 142         master = spi_alloc_master(&pdev->dev, sizeof(*sp));
 143         if (master == NULL) {
 144                 dev_err(&pdev->dev, "failed to allocate spi master\n");
 145 @@ -215,17 +235,10 @@ static __devinit int ath79_spi_probe(str
 146         sp = spi_master_get_devdata(master);
 147         platform_set_drvdata(pdev, sp);
 148
 149 -       pdata = pdev->dev.platform_data;
 150 -
 151         master->setup = ath79_spi_setup;
 152         master->cleanup = ath79_spi_cleanup;
 153 -       if (pdata) {
 154 -               master->bus_num = pdata->bus_num;
 155 -               master->num_chipselect = pdata->num_chipselect;
 156 -       } else {
 157 -               master->bus_num = -1;
 158 -               master->num_chipselect = 1;
 159 -       }
 160 +       master->bus_num = pdata->bus_num;
 161 +       master->num_chipselect = pdata->num_chipselect;
 162
 163         sp->bitbang.master = spi_master_get(master);
 164         sp->bitbang.chipselect = ath79_spi_chipselect;