target/linux/s3c24xx/patches-2.6.26/1090-fix-lis302dl-suspend-gpio.patch.patch

   1 From f97c81869175362f755488bd50ddf85570236ce8 Mon Sep 17 00:00:00 2001
   2 From: Andy Green <andy@openmoko.com>
   3 Date: Fri, 25 Jul 2008 23:06:02 +0100
   4 Subject: [PATCH] fix-lis302dl-suspend-gpio.patch
   5  Add platform stuff to deal with going in and out of suspend
   6  so the motion sensor IO is not driving high into unpowered sensors
   7
   8 Signed-off-by: Andy Green <andy@openmoko.com>
   9 ---
  10  arch/arm/mach-s3c2440/mach-gta02.c |   28 +++++++++++++++++++++++++++-
  11  drivers/input/misc/lis302dl.c      |   15 +++++++++++++++
  12  include/linux/lis302dl.h           |    1 +
  13  3 files changed, 43 insertions(+), 1 deletions(-)
  14
  15 diff --git a/arch/arm/mach-s3c2440/mach-gta02.c b/arch/arm/mach-s3c2440/mach-gta02.c
  16 index 5bd68a6..99206ee 100644
  17 --- a/arch/arm/mach-s3c2440/mach-gta02.c
  18 +++ b/arch/arm/mach-s3c2440/mach-gta02.c
  19 @@ -887,7 +887,31 @@ void gat02_lis302dl_bitbang_read(struct lis302dl_info *lis)
  20  }
  21
  22
  23 -struct lis302dl_platform_data lis302_pdata[] = {
  24 +void gat02_lis302dl_suspend_io(struct lis302dl_info *lis, int resume)
  25 +{
  26 +       struct lis302dl_platform_data *pdata = lis->pdata;
  27 +
  28 +       if (!resume) {
  29 +                /*
  30 +                * we don't want to power them with a high level
  31 +                * because GSENSOR_3V3 is not up during suspend
  32 +                */
  33 +               s3c2410_gpio_setpin(pdata->pin_chip_select, 0);
  34 +               s3c2410_gpio_setpin(pdata->pin_clk, 0);
  35 +               s3c2410_gpio_setpin(pdata->pin_mosi, 0);
  36 +               /* misnomer: it is a pullDOWN in 2442 */
  37 +               s3c2410_gpio_pullup(pdata->pin_miso, 1);
  38 +               return;
  39 +       }
  40 +
  41 +       /* back to normal */
  42 +       s3c2410_gpio_setpin(pdata->pin_chip_select, 1);
  43 +       s3c2410_gpio_setpin(pdata->pin_clk, 1);
  44 +       /* misnomer: it is a pullDOWN in 2442 */
  45 +       s3c2410_gpio_pullup(pdata->pin_miso, 0);
  46 +}
  47 +
  48 +const struct lis302dl_platform_data lis302_pdata[] = {
  49         {
  50                 .name           = "lis302-1 (top)",
  51                 .pin_chip_select= S3C2410_GPD12,
  52 @@ -896,6 +920,7 @@ struct lis302dl_platform_data lis302_pdata[] = {
  53                 .pin_miso       = S3C2410_GPG5,
  54                 .open_drain     = 1, /* altered at runtime by PCB rev */
  55                 .lis302dl_bitbang_read = gat02_lis302dl_bitbang_read,
  56 +               .lis302dl_suspend_io = gat02_lis302dl_suspend_io,
  57         }, {
  58                 .name           = "lis302-2 (bottom)",
  59                 .pin_chip_select= S3C2410_GPD13,
  60 @@ -904,6 +929,7 @@ struct lis302dl_platform_data lis302_pdata[] = {
  61                 .pin_miso       = S3C2410_GPG5,
  62                 .open_drain     = 1, /* altered at runtime by PCB rev */
  63                 .lis302dl_bitbang_read = gat02_lis302dl_bitbang_read,
  64 +               .lis302dl_suspend_io = gat02_lis302dl_suspend_io,
  65         },
  66  };
  67
  68 diff --git a/drivers/input/misc/lis302dl.c b/drivers/input/misc/lis302dl.c
  69 index 36bdcf7..2be816a 100644
  70 --- a/drivers/input/misc/lis302dl.c
  71 +++ b/drivers/input/misc/lis302dl.c
  72 @@ -428,6 +428,15 @@ static int lis302dl_suspend(struct spi_device *spi, pm_message_t state)
  73         disable_irq(lis->spi_dev->irq);
  74         local_save_flags(flags);
  75
  76 +       /*
  77 +        * When we share SPI over multiple sensors, there is a race here
  78 +        * that one or more sensors will lose.  In that case, the shared
  79 +        * SPI bus GPIO will be in sleep mode and partially pulled down.  So
  80 +        * we explicitly put our IO into "wake" mode here before the final
  81 +        * traffic to the sensor.
  82 +        */
  83 +       (lis->pdata->lis302dl_suspend_io)(lis, 1);
  84 +
  85         /* save registers */
  86         lis->regs[LIS302DL_REG_CTRL1] = reg_read(lis, LIS302DL_REG_CTRL1);
  87         lis->regs[LIS302DL_REG_CTRL2] = reg_read(lis, LIS302DL_REG_CTRL2);
  88 @@ -467,6 +476,9 @@ static int lis302dl_suspend(struct spi_device *spi, pm_message_t state)
  89                 reg_write(lis, LIS302DL_REG_CTRL1, tmp);
  90         }
  91
  92 +       /* place our IO to the device in sleep-compatible states */
  93 +       (lis->pdata->lis302dl_suspend_io)(lis, 0);
  94 +
  95         local_irq_restore(flags);
  96
  97         return 0;
  98 @@ -479,6 +491,9 @@ static int lis302dl_resume(struct spi_device *spi)
  99
 100         local_save_flags(flags);
 101
 102 +       /* get our IO to the device back in operational states */
 103 +       (lis->pdata->lis302dl_suspend_io)(lis, 1);
 104 +
 105         /* restore registers after resume */
 106         reg_write(lis, LIS302DL_REG_CTRL1, lis->regs[LIS302DL_REG_CTRL1]);
 107         reg_write(lis, LIS302DL_REG_CTRL2, lis->regs[LIS302DL_REG_CTRL2]);
 108 diff --git a/include/linux/lis302dl.h b/include/linux/lis302dl.h
 109 index 2dea813..0d6b4c4 100644
 110 --- a/include/linux/lis302dl.h
 111 +++ b/include/linux/lis302dl.h
 112 @@ -16,6 +16,7 @@ struct lis302dl_platform_data {
 113         unsigned long pin_miso;
 114         int open_drain;
 115         void (*lis302dl_bitbang_read)(struct lis302dl_info *);
 116 +       void (*lis302dl_suspend_io)(struct lis302dl_info *, int resuming);
 117  };
 118
 119  struct lis302dl_info {
 120 --
 121 1.5.6.3
 122