misc: max9635: Fix issues with LUX register read

Modified driver to report lux every 2 secs.
Also rearranged data/removed unused variables in header file.

Change-Id: I3261a51497b2a55be735fbc73a6f15f7838b0b27
Signed-off-by: Praveen Bharathi <pbharathi@motorola.com>

diff --git a/drivers/misc/max9635.c b/drivers/misc/max9635.c
index c58f4f02f6226c2a896b62e61cea114640c6aafb..9e724ee8bc995b5e5ea0fb531f255f5ccd1524cd 100644 (file)
--- a/drivers/misc/max9635.c
+++ b/drivers/misc/max9635.c
@@ -190,63 +190,66 @@ static irqreturn_t max9635_irq_handler(int irq, void *dev)
        disable_irq_nosync(als_data->client->irq);
        schedule_delayed_work(&als_data->working_queue, 0);
 
-
        return IRQ_HANDLED;
 }
 
 static int max9635_read_adj_als(struct max9635_data *als_data)
 {
        int ret;
-       int i;
        int lux = 0;
        u8 buf[2] = { MAX9635_ALS_DATA_H, 0 };
+       u8 low_buf = MAX9635_ALS_DATA_L;
+       u8 high_buf = MAX9635_ALS_DATA_H;
        u8 exponent;
        u16 mantissa;
 
-       ret = max9635_read_reg(als_data, buf, 2);
+       ret = max9635_read_reg(als_data, &high_buf, 1);
        if (ret != 0) {
-               pr_err("%s:Unable to read interrupt register: %d\n",
+               pr_err("%s: Unable to read lux high byte register: %d\n",
+                      __func__, ret);
+               return -1;
+       }
+       ret = max9635_read_reg(als_data, &low_buf, 1);
+       if (ret != 0) {
+               pr_err("%s: Unable to read lux low byte register: %d\n",
                       __func__, ret);
                return -1;
        }
 
-       exponent = (buf[0] & 0xf0) >> 4;
-       mantissa = ((buf[0] & 0x0f) << 8) + buf[1];
-       /* lux = 2^exponent * mantissa / 32 */
-       lux = (mantissa << exponent) >> 5;
-       /* TO DO: Need to include lens loss coeffcient to achieve closer to
-          absolute lux value
-          if (als_data->als_pdata->lens_percent_t)
-          lux = ((10000 / als_data->als_pdata->lens_percent_t)*
-          (als_read_data)) / 100; */
-
-       for (i = 0; i < als_data->als_pdata->num_of_zones; i++) {
-               if ((lux <= als_data->max9635_zone_info[i].upper_threshold)
-                       && (lux >= als_data->max9635_zone_info[i].lower_threshold)) {
-                       if (max9635_debug & 1)
-                               pr_info("%s:Setting next window to %i\n",
-                                       __func__, i);
-
-                       buf[0] = (AUTO_INCREMENT | MAX9635_ALS_THRESH_L);
-                       buf[1] =
-                           als_data->als_pdata->als_lux_table[i].als_lower_threshold;
-                       ret = max9635_write_reg(als_data, buf, 1);
-                       if (ret != 0) {
-                               pr_err("%s:Unable to write reg: %d\n",
-                                      __func__, buf[0]);
-                               return -1;
-                       }
-                       buf[0] = (AUTO_INCREMENT | MAX9635_ALS_THRESH_H);
-                       buf[1] =
-                           als_data->als_pdata->als_lux_table[i].als_higher_threshold;
-                       ret = max9635_write_reg(als_data, buf, 1);
-                       if (ret != 0) {
-                               pr_err("%s:Unable to write reg: %d\n",
-                                      __func__, buf[0]);
-                               return -1;
-                       }
-               }
+       exponent = (high_buf & 0xf0) >> 4;
+       mantissa = ((high_buf & 0x0f) << 4) | (low_buf & 0x0f);
+
+       lux = ((0001 << exponent) * mantissa) / 20;
+       if (max9635_debug & 1)
+               pr_info("exp = 0x%X, mant = 0x%X, lux = %d\n",
+                       exponent, mantissa, lux);
+
+       /* lux can be in the range of 0 to 208896, per maxim */
+       if (lux == 0)
+               lux += 1;
+       if (lux == 208896)
+               lux -= 1;
+
+       buf[0] = (AUTO_INCREMENT | MAX9635_ALS_THRESH_L);
+       buf[1] = lux - 1;
+       ret = max9635_write_reg(als_data, buf, 1);
+       if (ret != 0) {
+               pr_err("%s:Unable to write reg: %d\n", __func__, buf[0]);
+               return -1;
+       }
+       if (max9635_debug & 1)
+               pr_err("lower threshold = %d\n", buf[1]);
+
+       buf[0] = (AUTO_INCREMENT | MAX9635_ALS_THRESH_H);
+       buf[1] = lux + 1;
+       ret = max9635_write_reg(als_data, buf, 1);
+       if (ret != 0) {
+               pr_err("%s:Unable to write reg: %d\n", __func__, buf[0]);
+               return -1;
        }
+       if (max9635_debug & 1)
+               pr_err("upper threshold = %d\n", buf[1]);
+
        if (max9635_debug & 1)
                pr_info("%s:Reporting LUX %d\n", __func__, lux);
        return lux;
@@ -448,46 +451,13 @@ static DEVICE_ATTR(registers, 0644, max9635_registers_show,
 
 static void max9635_work_queue(struct work_struct *work)
 {
-       struct max9635_data *als_data = container_of((struct delayed_work *)work,
-               struct max9635_data, working_queue);
+       struct max9635_data *als_data =
+               container_of((struct delayed_work *)work, struct max9635_data,
+                            working_queue);
 
        max9635_report_input(als_data);
 }
 
-static void max9635_convert_zones(struct max9635_data *als_data)
-{
-       int i = 0;
-       int lux = 0;
-       u8 exponent;
-       u8 mantissa;
-
-       /* Convert the byte to a lux value based
-       on the equation in the data sheet */
-       for (i = 0; i < als_data->als_pdata->num_of_zones; i++) {
-               exponent =
-                   (als_data->als_pdata->als_lux_table[i].als_lower_threshold & 0xf0) >> 4;
-               mantissa =
-                   ((als_data->als_pdata->als_lux_table[i].als_lower_threshold & 0x0f) << 4);
-               /* lux = 2^exponent * mantissa / 32 */
-               lux = (mantissa << exponent) >> 5;
-               als_data->max9635_zone_info[i].lower_threshold = lux;
-
-               exponent =
-                   (als_data->als_pdata->als_lux_table[i].
-                    als_higher_threshold & 0xf0) >> 4;
-               mantissa =
-                   ((als_data->als_pdata->als_lux_table[i].als_higher_threshold & 0x0f) << 4) | 0x0f;
-               /* lux = 2^exponent * mantissa / 32 */
-               lux = (mantissa << exponent) >> 5;
-               als_data->max9635_zone_info[i].upper_threshold = lux;
-
-               pr_info("%s:Element %i Upper %d Lower %d\n", __func__, i,
-                      als_data->max9635_zone_info[i].upper_threshold,
-                      als_data->max9635_zone_info[i].lower_threshold);
-       }
-       return;
-}
-
 static int max9635_probe(struct i2c_client *client,
                         const struct i2c_device_id *id)
 {
@@ -528,8 +498,6 @@ static int max9635_probe(struct i2c_client *client,
        input_set_capability(als_data->idev, EV_MSC, MSC_RAW);
        input_set_capability(als_data->idev, EV_LED, LED_MISC);
 
-       max9635_convert_zones(als_data);
-
        error = misc_register(&max9635_misc_device);
        if (error < 0) {
                pr_err("%s: max9635 register failed\n", __func__);

diff --git a/include/linux/max9635.h b/include/linux/max9635.h
index aa514d8e89d792c9cae3a18584ca0cac8c5c8f58..4968a6835e675361204fc1044e8b2045c307ff3f 100644 (file)
--- a/include/linux/max9635.h
+++ b/include/linux/max9635.h
@@ -23,19 +23,13 @@
 
 #ifdef __KERNEL__
 
-struct max9635_als_zone_data {
-       int  als_lower_threshold;
-       int  als_higher_threshold;
-};
-
 struct max9635_platform_data {
-       u8      configure;
-       u8      threshold_timer;
-       u8      def_low_threshold;
-       u8      def_high_threshold;
-       u32 lens_percent_t;
-       struct max9635_als_zone_data *als_lux_table;
-       u8  num_of_zones;
+       u8 configure;
+       u8 threshold_timer;
+       u8 def_low_threshold;
+       u8 def_high_threshold;
+       int (*power_on)(void);
+       int (*power_off)(void);
 };
 
 #endif /* __KERNEL__ */