From 33a99c7458ee154f18b20f6db15d73397a1a7b55 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Tomasz=20Paku=C5=82a?= <forest10pl@gmail.com>
Date: Tue, 2 Jul 2024 11:52:46 +0200
Subject: [PATCH] Add field value clamping functionality

---
 hid-pidff.c | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/hid-pidff.c b/hid-pidff.c
index 7551253..710f6a5 100644
--- a/hid-pidff.c
+++ b/hid-pidff.c
@@ -213,6 +213,36 @@ static int pidff_rescale_signed(int i, struct hid_field *field)
 	    field->logical_minimum / -0x8000;
 }
 
+/*
+ * Clamp minimum value for the given field
+ */
+static int pidff_clamp_min(int i, struct hid_field *field)
+{
+	int ret =  i < field->logical_minimum ? field->logical_minimum : i;
+	pr_debug("clamped min value from %d to %d\n", i, ret);
+	return ret;
+}
+
+/*
+ * Clamp maximum value for the given field
+ */
+static int pidff_clamp_max(int i, struct hid_field *field)
+{
+	int ret = i > field->logical_maximum ? field->logical_maximum : i;
+	pr_debug("clamped max value from %d to %d\n", i, ret);
+	return ret;
+}
+
+/*
+ * Clamp value for the given field
+ */
+static int pidff_clamp(int i, struct hid_field *field)
+{
+	i = pidff_clamp_min(i, field);
+	i = pidff_clamp_max(i, field);
+	return i;
+}
+
 static void pidff_set(struct pidff_usage *usage, u16 value)
 {
 	usage->value[0] = pidff_rescale(value, 0xffff, usage->field);
@@ -359,7 +389,7 @@ static void pidff_set_periodic_report(struct pidff_device *pidff,
 	pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
 			 effect->u.periodic.offset);
 	pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
-	pidff->set_periodic[PID_PERIOD].value[0] = effect->u.periodic.period;
+	pidff->set_periodic[PID_PERIOD].value[0] = pidff_clamp(effect->u.periodic.period, pidff->set_periodic[PID_PERIOD].field);
 
 	hid_hw_request(pidff->hid, pidff->reports[PID_SET_PERIODIC],
 			HID_REQ_SET_REPORT);