[PATCH 2/5]: lis302dl-threshold-configuration-in-mg.patch

[Simon Kagstrom]

Change the threshold configuration to be set in mg instead

From: Simon Kagstrom <[EMAIL PROTECTED]>

This patch changes the threshold sysfs file to handle values in mg
instead of the device-values. Overrun values have also been corrected
and the sampler function now honors the FS bit.

Signed-off-by: Simon Kagstrom <[EMAIL PROTECTED]>
---

 drivers/input/misc/lis302dl.c |   49 +++++++++++++++++++++++++++++++++--------
 1 files changed, 39 insertions(+), 10 deletions(-)

diff --git a/drivers/input/misc/lis302dl.c b/drivers/input/misc/lis302dl.c
index 300918d..c1b1d67 100644
--- a/drivers/input/misc/lis302dl.c
+++ b/drivers/input/misc/lis302dl.c
@@ -97,6 +97,24 @@ static int __duration_to_ms(struct lis302dl_info *lis, int 
duration)
        return duration * 10;
 }
 
+static u8 __mg_to_threshold(struct lis302dl_info *lis, int mg)
+{
+       /* If FS is set each bit is 71mg, otherwise 18mg. The THS register
+        * has 7 bits for the threshold value */
+       if (lis->flags & LIS302DL_F_FS)
+               return min(mg / 71, 127);
+
+       return min(mg / 18, 127);
+}
+
+static int __threshold_to_mg(struct lis302dl_info *lis, u8 threshold)
+{
+       if (lis->flags & LIS302DL_F_FS)
+               return threshold * 71;
+
+       return threshold * 18;
+}
+
 /* interrupt handling related */
 
 enum lis302dl_intmode {
@@ -146,23 +164,24 @@ static void _report_btn_double(struct input_dev *inp, int 
btn)
 }
 #endif
 
-#define MG_PER_SAMPLE 18
 
 static void lis302dl_bitbang_read_sample(struct lis302dl_info *lis)
 {
        u8 data = 0xc0 | LIS302DL_REG_OUT_X; /* read, autoincrement */
        u8 read[5];
        unsigned long flags;
+       int mg_per_sample;
 
        local_irq_save(flags);
+       mg_per_sample = __threshold_to_mg(lis, 1);
 
        (lis->pdata->lis302dl_bitbang)(lis, &data, 1, &read[0], 5);
 
        local_irq_restore(flags);
 
-       input_report_rel(lis->input_dev, REL_X, MG_PER_SAMPLE * (s8)read[0]);
-       input_report_rel(lis->input_dev, REL_Y, MG_PER_SAMPLE * (s8)read[2]);
-       input_report_rel(lis->input_dev, REL_Z, MG_PER_SAMPLE * (s8)read[4]);
+       input_report_rel(lis->input_dev, REL_X, mg_per_sample * (s8)read[0]);
+       input_report_rel(lis->input_dev, REL_Y, mg_per_sample * (s8)read[2]);
+       input_report_rel(lis->input_dev, REL_Z, mg_per_sample * (s8)read[4]);
 
        input_sync(lis->input_dev);
 
@@ -234,15 +253,24 @@ static ssize_t set_scale(struct device *dev, struct 
device_attribute *attr,
 {
        struct lis302dl_info *lis = dev_get_drvdata(dev);
        unsigned long flags;
+       int threshold_mg = __threshold_to_mg(lis, lis->threshold);
 
        local_irq_save(flags);
 
-       if (!strcmp(buf, "9.2\n"))
+       if (!strcmp(buf, "9.2\n")) {
                __reg_set_bit_mask(lis, LIS302DL_REG_CTRL1, LIS302DL_CTRL1_FS,
                                 LIS302DL_CTRL1_FS);
-       else
+               lis->flags |= LIS302DL_F_FS;
+       } else {
                __reg_set_bit_mask(lis, LIS302DL_REG_CTRL1, LIS302DL_CTRL1_FS,
-                                                                            0);
+                               0);
+               lis->flags &= ~LIS302DL_F_FS;
+       }
+
+       /* Adjust the threshold */
+       lis->threshold = __mg_to_threshold(lis, threshold_mg);
+       if (lis->flags & LIS302DL_F_INPUT_OPEN)
+               __reg_write(lis, LIS302DL_REG_FF_WU_THS_1, lis->threshold);
 
        local_irq_restore(flags);
 
@@ -256,7 +284,7 @@ static ssize_t show_threshold(struct device *dev, struct 
device_attribute *attr,
 {
        struct lis302dl_info *lis = dev_get_drvdata(dev);
 
-       return sprintf(buf, "%d\n", lis->threshold);
+       return sprintf(buf, "%d\n", __threshold_to_mg(lis, lis->threshold));
 }
 
 static ssize_t set_threshold(struct device *dev, struct device_attribute *attr,
@@ -267,11 +295,12 @@ static ssize_t set_threshold(struct device *dev, struct 
device_attribute *attr,
 
        if (sscanf(buf, "%d\n", &val) != 1)
                return -EINVAL;
-       if (val < 0 || val > 255)
+       /* 8g is the maximum if FS is 1 */
+       if (val < 0 || val > 8000)
                return -ERANGE;
 
        /* Set the threshold and write it out if the device is used */
-       lis->threshold = val;
+       lis->threshold = __mg_to_threshold(lis, val);
        if (lis->flags & LIS302DL_F_INPUT_OPEN)
                __reg_write(lis, LIS302DL_REG_FF_WU_THS_1, lis->threshold);