Use non-void configurations

This patch defines a ts_filter_configuration structure to
avoid using void* in the filter initialization, fixing another
upstream correction. This also makes the initialization more readable.

Tested in GTA02/rev6.

Other changes:

 ~ Comment filter configuration structures.
 ~ ts_filter.c:ts_filter_chain_create improved.
 ~ Small cleanups.
 ~ More TODOs/FIXMEs.
 ~ Updated GTA02 filter configuration.
 ~ Updated GTA01 filter configuration.
 ~ Updated mach-s3c2410/include/mach/ts.h for the new ts. configuration
   structure.
 ~ Updated all the filters to use the new configuration structure.
 ~ Removed MAX_TS_FILTER_CHAIN constant that is no longer needed.

No more evil casts left it seems.

Signed-off-by: Nelson Castillo <arhuaco@freaks-unidos.net>

12 files changed, 103 insertions, 51 deletions

diff --git a/drivers/input/touchscreen/pcap7200_ts.c b/drivers/input/touchscreen/pcap7200_ts.c
index e8e9cc6f932..5a111f080e9 100644
--- a/drivers/input/touchscreen/pcap7200_ts.c
+++ b/drivers/input/touchscreen/pcap7200_ts.c
@@ -43,7 +43,7 @@
 struct pcap7200_data{
 	struct i2c_client *client;
 	struct input_dev *dev;
-	struct ts_filter *tsf[MAX_TS_FILTER_CHAIN];
+	struct ts_filter **tsf;
 	struct mutex lock;
 	int irq;
 	struct work_struct work;
diff --git a/drivers/input/touchscreen/s3c2410_ts.c b/drivers/input/touchscreen/s3c2410_ts.c
index d63d4eab605..ccd4a444148 100644
--- a/drivers/input/touchscreen/s3c2410_ts.c
+++ b/drivers/input/touchscreen/s3c2410_ts.c
@@ -98,7 +98,6 @@ static char *s3c2410ts_name = "s3c2410 TouchScreen";
 
 #define TS_RELEASE_TIMEOUT (HZ >> 7 ? HZ >> 7 : 1) /* 8ms (5ms if HZ is 200) */
 #define TS_EVENT_FIFO_SIZE (2 << 6) /* must be a power of 2 */
-#define TS_COORDINATES_SIZE 2		/* just X and Y for us */
 
 #define TS_STATE_STANDBY 0 /* initial state */
 #define TS_STATE_PRESSED 1
@@ -411,9 +410,7 @@ static int __init s3c2410ts_probe(struct platform_device *pdev)
 	}
 
 	/* create the filter chain set up for the 2 coordinates we produce */
-	ts.tsf = ts_filter_chain_create(
-			pdev, (struct ts_filter_api **)&info->filter_sequence,
-			(void *)&info->filter_config, TS_COORDINATES_SIZE);
+	ts.tsf = ts_filter_chain_create(pdev, info->filter_config, 2);
 
 	if (!ts.tsf)
 		goto bail2;
diff --git a/drivers/input/touchscreen/ts_filter.c b/drivers/input/touchscreen/ts_filter.c
index 817fff23154..5551fe32b49 100644
--- a/drivers/input/touchscreen/ts_filter.c
+++ b/drivers/input/touchscreen/ts_filter.c
@@ -40,11 +40,11 @@ static int sptrlen(void *arr)
 	return len;
 }
 
-static struct ts_filter **revchain; /* FIXME: rename this temporal hack. */
+/* FIXME: rename & remove this temporal hack. */
+static struct ts_filter **revchain;
 
 struct ts_filter **ts_filter_chain_create(struct platform_device *pdev,
-					  struct ts_filter_api **api,
-					  void **config,
+					  struct ts_filter_configuration conf[],
 					  int count_coords)
 {
 	struct ts_filter **arr;
@@ -55,28 +55,31 @@ struct ts_filter **ts_filter_chain_create(struct platform_device *pdev,
 	BUG_ON((count_coords < 1));
 	BUG_ON(count_coords > MAX_TS_FILTER_COORDS);
 
-	len = (sptrlen(api) + 1);
+	len = (sptrlen(conf) + 1);
 	/* memory for two null-terminated arrays of filters */
 	arr = kzalloc(2 * sizeof(struct ts_filter *) * len, GFP_KERNEL);
 	if (!arr)
 		goto create_err;
 	revchain = arr + len;
 
-	while (*api) {
-		/* TODO: Can get away with only sending pdev->dev? */
-		/* FIXME: Avoid config (void**) */
-		struct ts_filter *f = ((*api)->create)(pdev, *config++,
-						       count_coords);
+	while (conf->api) {
+		/* TODO: Can we get away with only sending pdev->dev? */
+		struct ts_filter *f =
+			(conf->api->create)(pdev, conf->config, count_coords);
 		if (!f) {
-			dev_info(&pdev->dev, "Filter %d failed init\n", count);
+			dev_info(&pdev->dev, "Filter %d creation failed\n",
+				 count);
 			goto create_err;
 		}
-		f->api = *(api++);
+
+		f->api = conf->api;
 		arr[count++] = f;
 
 		/* Filters that can propagate values in the chain. */
 		if (f->api->haspoint && f->api->getpoint && f->api->process)
 			revchain[nrev++] = f;
+
+		conf++;
 	}
 
 	dev_info(&pdev->dev, "%d filter(s) initialized\n", count);
diff --git a/drivers/input/touchscreen/ts_filter.h b/drivers/input/touchscreen/ts_filter.h
index b5e8c7c3845..630ea51aa78 100644
--- a/drivers/input/touchscreen/ts_filter.h
+++ b/drivers/input/touchscreen/ts_filter.h
@@ -9,16 +9,17 @@
 
 #include <linux/platform_device.h>
 
-#define MAX_TS_FILTER_CHAIN		8  /* Max. filters we can chain up. */
 #define MAX_TS_FILTER_COORDS		3  /* X, Y and Z (pressure). */
 
 struct ts_filter;
+struct ts_filter_configuration;
 
 /* Operations that a filter can perform. */
 
 struct ts_filter_api {
 	/* Create the filter - mandatory. */
-	struct ts_filter * (*create)(struct platform_device *pdev, void *config,
+	struct ts_filter * (*create)(struct platform_device *pdev,
+				     struct ts_filter_configuration *config,
 				     int count_coords);
 	/* Destroy the filter - mandatory. */
 	void (*destroy)(struct ts_filter *filter);
@@ -56,15 +57,21 @@ struct ts_filter_api {
 };
 
 /*
- * This is the common part of all filters.
- * We use this type as an otherwise opaque handle on to
- * the actual filter.  Therefore you need one of these
- * at the start of your actual filter struct.
+ * Generic filter configuration. Actual configurations have this structure
+ * as a member.
  */
+struct ts_filter_configuration {
+	/* API to use */
+	struct ts_filter_api *api;
+	/* Generic filter configuration. Different for each filter. */
+	struct ts_filter_configuration *config;
+};
+
 struct ts_filter {
-	struct ts_filter_api *api;	/* operations for this filter */
-	int count_coords;		/* how many coordinates to process */
-	int coords[MAX_TS_FILTER_COORDS];	/* count_coords coordinates */
+	/* Operations for this filter. */
+	struct ts_filter_api *api;
+	/* Number of coordinates to process. */
+	int count_coords;
 };
 
 #ifdef CONFIG_TOUCHSCREEN_FILTER
@@ -75,7 +82,8 @@ struct ts_filter {
  */
 extern struct ts_filter **ts_filter_chain_create(
 	struct platform_device *pdev,
-	struct ts_filter_api **api, void **config, int count_coords);
+	struct ts_filter_configuration conf[],
+	int count_coords);
 
 /* Helper to destroy a whole chain from the list of filter pointers. */
 extern void ts_filter_chain_destroy(struct ts_filter **arr);
@@ -94,7 +102,7 @@ extern void ts_filter_chain_clear(struct ts_filter **arr);
 int ts_filter_chain_feed(struct ts_filter **arr, int *coords);
 
 #else /* !CONFIG_TOUCHSCREEN_FILTER */
-#define ts_filter_chain_create(pdev, api, config, arr, count_coords) (0)
+#define ts_filter_chain_create(pdev, config, count_coords) (0) /*TODO:fail!*/
 #define ts_filter_chain_destroy(pdev, arr) do { } while (0)
 #define ts_filter_chain_clear(arr) do { } while (0)
 #define ts_filter_chain_feed(arr, coords) (1)
diff --git a/drivers/input/touchscreen/ts_filter_group.c b/drivers/input/touchscreen/ts_filter_group.c
index 9b02c70c4bb..ac3229fcff2 100644
--- a/drivers/input/touchscreen/ts_filter_group.c
+++ b/drivers/input/touchscreen/ts_filter_group.c
@@ -83,8 +83,10 @@ static void ts_filter_group_clear(struct ts_filter *tsf)
 	ts_filter_group_clear_internal(tsfg, tsfg->config->attempts);
 }
 
-static struct ts_filter *ts_filter_group_create(struct platform_device *pdev,
-						void *conf, int count_coords)
+static struct ts_filter *ts_filter_group_create(
+	struct platform_device *pdev,
+	struct ts_filter_configuration *conf,
+	int count_coords)
 {
 	struct ts_filter_group *tsfg;
 	int i;
@@ -93,28 +95,30 @@ static struct ts_filter *ts_filter_group_create(struct platform_device *pdev,
 	if (!tsfg)
 		return NULL;
 
-	tsfg->config = (struct ts_filter_group_configuration *)conf;
+	tsfg->config = container_of(conf,
+				    struct ts_filter_group_configuration,
+				    config);
 	tsfg->tsf.count_coords = count_coords;
 
 	BUG_ON(tsfg->config->attempts <= 0);
 
 	tsfg->samples[0] = kmalloc((2 + count_coords) * sizeof(int) *
-				   tsfg->config->extent, GFP_KERNEL);
+				   tsfg->config->length, GFP_KERNEL);
 	if (!tsfg->samples[0]) {
 		kfree(tsfg);
 		return NULL;
 	}
 	for (i = 1; i < count_coords; ++i)
-		tsfg->samples[i] = tsfg->samples[0] + i * tsfg->config->extent;
+		tsfg->samples[i] = tsfg->samples[0] + i * tsfg->config->length;
 	tsfg->sorted_samples = tsfg->samples[0] + count_coords *
-			       tsfg->config->extent;
+			       tsfg->config->length;
 	tsfg->group_size = tsfg->samples[0] + (1 + count_coords) *
-			       tsfg->config->extent;
+			       tsfg->config->length;
 
 	ts_filter_group_clear_internal(tsfg, tsfg->config->attempts);
 
 	dev_info(&pdev->dev, "Created Group filter len:%d coords:%d close:%d "
-		 "thresh:%d\n", tsfg->config->extent, count_coords,
+		 "thresh:%d\n", tsfg->config->length, count_coords,
 		 tsfg->config->close_enough, tsfg->config->threshold);
 
 	return &tsfg->tsf;
@@ -148,13 +152,13 @@ static int ts_filter_group_process(struct ts_filter *tsf, int *coords)
 	int n;
 	int i;
 
-	BUG_ON(tsfg->N >= tsfg->config->extent);
+	BUG_ON(tsfg->N >= tsfg->config->length);
 	BUG_ON(tsfg->ready);
 
 	for (n = 0; n < tsf->count_coords; n++)
 		tsfg->samples[n][tsfg->N] = coords[n];
 
-	if (++tsfg->N < tsfg->config->extent)
+	if (++tsfg->N < tsfg->config->length)
 		return 0;	/* We need more samples. */
 
 	for (n = 0; n < tsfg->tsf.count_coords; n++) {
diff --git a/drivers/input/touchscreen/ts_filter_group.h b/drivers/input/touchscreen/ts_filter_group.h
index c13b0c487df..4fc2af70608 100644
--- a/drivers/input/touchscreen/ts_filter_group.h
+++ b/drivers/input/touchscreen/ts_filter_group.h
@@ -12,10 +12,23 @@
  */
 
 struct ts_filter_group_configuration {
-	int extent;
+	/* Size of the filter. */
+	int length;
+	/*
+	 * If two points are separated by this distance or less they
+	 * are considered to be members of the same group.
+	 */
 	int close_enough;
+	/* Minimum allowed size for the biggest group in the sample set. */
 	int threshold;
+	/*
+	 * Number of times we try to get a group of points with at least
+	 * threshold points.
+	 */
 	int attempts;
+
+	/* Generic filter configuration. */
+	struct ts_filter_configuration config;
 };
 
 extern struct ts_filter_api ts_filter_group_api;
diff --git a/drivers/input/touchscreen/ts_filter_linear.c b/drivers/input/touchscreen/ts_filter_linear.c
index 72a362f7567..bb6381457a8 100644
--- a/drivers/input/touchscreen/ts_filter_linear.c
+++ b/drivers/input/touchscreen/ts_filter_linear.c
@@ -125,8 +125,10 @@ static ssize_t const_store(struct const_obj *obj, struct const_attribute *attr,
 
 /* Filter functions. */
 
-static struct ts_filter *ts_filter_linear_create(struct platform_device *pdev,
-						 void *conf, int count_coords)
+static struct ts_filter *ts_filter_linear_create(
+	struct platform_device *pdev,
+	struct ts_filter_configuration *conf,
+	int count_coords)
 {
 	struct ts_filter_linear *tsfl;
 	int i;
@@ -136,7 +138,10 @@ static struct ts_filter *ts_filter_linear_create(struct platform_device *pdev,
 	if (!tsfl)
 		return NULL;
 
-	tsfl->config = (struct ts_filter_linear_configuration *)conf;
+	tsfl->config = container_of(conf,
+				    struct ts_filter_linear_configuration,
+				    config);
+
 	tsfl->tsf.count_coords = count_coords;
 
 	for (i = 0; i < TS_FILTER_LINEAR_NCONSTANTS; ++i) {
diff --git a/drivers/input/touchscreen/ts_filter_linear.h b/drivers/input/touchscreen/ts_filter_linear.h
index 9da5b82881c..5cd9a81158d 100644
--- a/drivers/input/touchscreen/ts_filter_linear.h
+++ b/drivers/input/touchscreen/ts_filter_linear.h
@@ -14,13 +14,16 @@
 
 #define TS_FILTER_LINEAR_NCONSTANTS 7
 
-/* filter configuration */
-
-/* FIXME: comment every field. */
 struct ts_filter_linear_configuration {
+	/* Calibration constants. */
 	int constants[TS_FILTER_LINEAR_NCONSTANTS];
+	/* First coordinate. */
 	int coord0;
+	/* Second coordinate. */
 	int coord1;
+
+	/* Generic filter configuration. */
+	struct ts_filter_configuration config;
 };
 
 extern struct ts_filter_api ts_filter_linear_api;
diff --git a/drivers/input/touchscreen/ts_filter_mean.c b/drivers/input/touchscreen/ts_filter_mean.c
index c61a5c1c3a0..291226e6fdb 100644
--- a/drivers/input/touchscreen/ts_filter_mean.c
+++ b/drivers/input/touchscreen/ts_filter_mean.c
@@ -50,8 +50,10 @@ struct ts_filter_mean {
 
 static void ts_filter_mean_clear(struct ts_filter *tsf);
 
-static struct ts_filter *ts_filter_mean_create(struct platform_device *pdev,
-					       void *config, int count_coords)
+static struct ts_filter *ts_filter_mean_create(
+	struct platform_device *pdev,
+	struct ts_filter_configuration *conf,
+	int count_coords)
 {
 	struct ts_filter_mean *priv;
 	int *v;
@@ -62,7 +64,9 @@ static struct ts_filter *ts_filter_mean_create(struct platform_device *pdev,
 		return NULL;
 
 	priv->tsf.count_coords = count_coords;
-	priv->config = (struct ts_filter_mean_configuration *)config;
+	priv->config = container_of(conf,
+				    struct ts_filter_mean_configuration,
+				    config);
 
 	BUG_ON(priv->config->length <= 0);
 
diff --git a/drivers/input/touchscreen/ts_filter_mean.h b/drivers/input/touchscreen/ts_filter_mean.h
index 5677ed89019..7b3935f9e0c 100644
--- a/drivers/input/touchscreen/ts_filter_mean.h
+++ b/drivers/input/touchscreen/ts_filter_mean.h
@@ -17,6 +17,9 @@
 struct ts_filter_mean_configuration {
 	/* Number of points for the mean. */
 	int length;
+
+	/* Generic filter configuration. */
+	struct ts_filter_configuration config;
 };
 
 /* API functions for the mean filter */
diff --git a/drivers/input/touchscreen/ts_filter_median.c b/drivers/input/touchscreen/ts_filter_median.c
index 6187abbb803..547ca8d818a 100644
--- a/drivers/input/touchscreen/ts_filter_median.c
+++ b/drivers/input/touchscreen/ts_filter_median.c
@@ -103,8 +103,10 @@ static void ts_filter_median_clear(struct ts_filter *tsf)
 	memset(&tsfm->last_issued[0], 1, tsf->count_coords * sizeof(int));
 }
 
-static struct ts_filter *ts_filter_median_create(struct platform_device *pdev,
-						 void *conf, int count_coords)
+static struct ts_filter *ts_filter_median_create(
+	struct platform_device *pdev,
+	struct ts_filter_configuration *conf,
+	int count_coords)
 {
 	int *p;
 	int n;
@@ -114,7 +116,10 @@ static struct ts_filter *ts_filter_median_create(struct platform_device *pdev,
 	if (!tsfm)
 		return NULL;
 
-	tsfm->config = (struct ts_filter_median_configuration *)conf;
+	tsfm->config = container_of(conf,
+				    struct ts_filter_median_configuration,
+				    config);
+
 	tsfm->tsf.count_coords = count_coords;
 
 	tsfm->config->midpoint = (tsfm->config->extent >> 1) + 1;
diff --git a/drivers/input/touchscreen/ts_filter_median.h b/drivers/input/touchscreen/ts_filter_median.h
index 589bc6d996c..17a1ca6d201 100644
--- a/drivers/input/touchscreen/ts_filter_median.h
+++ b/drivers/input/touchscreen/ts_filter_median.h
@@ -11,13 +11,20 @@
  * (c) 2008 Andy Green <andy@openmoko.com>
  */
 
-/* TODO: comment every field */
 struct ts_filter_median_configuration {
+	/* Size of the filter. */
 	int extent;
+	/* Precomputed midpoint. */
 	int midpoint;
+	/* A reference value for us to check if we are going fast or slow. */
 	int decimation_threshold;
+	/* How many points to replace if we're going fast. */
 	int decimation_above;
+	/* How many points to replace if we're going slow. */
 	int decimation_below;
+
+	/* Generic configuration. */
+	struct ts_filter_configuration config;
 };
 
 extern struct ts_filter_api ts_filter_median_api;