thermal: rcar_gen3_thermal: Store thcode and ptat in priv data

Prepare for reading the THCODE and PTAT values from hardware fuses by
storing the values used during calculations in the drivers private
data structures.

As the values are now stored directly in the private data structures
there is no need to keep track of the TSC channel id as its only usage
was to lookup the THCODE row, drop it.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20211014103816.1939782-2-niklas.soderlund+renesas@ragnatech.seSigned-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

drivers/thermal/rcar_gen3_thermal.c

@@ -62,15 +62,6 @@
 
 #define TSC_MAX_NUM	5
 
-/* default THCODE values if FUSEs are missing */
-static const int thcodes[TSC_MAX_NUM][3] = {
-	{ 3397, 2800, 2221 },
-	{ 3393, 2795, 2216 },
-	{ 3389, 2805, 2237 },
-	{ 3415, 2694, 2195 },
-	{ 3356, 2724, 2244 },
-};
-
 /* Structure for thermal temperature calculation */
 struct equation_coefs {
 	int a1;
@@ -84,13 +75,14 @@ struct rcar_gen3_thermal_tsc {
 	struct thermal_zone_device *zone;
 	struct equation_coefs coef;
 	int tj_t;
-	unsigned int id; /* thermal channel id */
+	int thcode[3];
 };
 
 struct rcar_gen3_thermal_priv {
 	struct rcar_gen3_thermal_tsc *tscs[TSC_MAX_NUM];
 	unsigned int num_tscs;
 	void (*thermal_init)(struct rcar_gen3_thermal_tsc *tsc);
+	int ptat[3];
 };
 
 static inline u32 rcar_gen3_thermal_read(struct rcar_gen3_thermal_tsc *tsc,
@@ -133,8 +125,8 @@ static inline void rcar_gen3_thermal_write(struct rcar_gen3_thermal_tsc *tsc,
 /* no idea where these constants come from */
 #define TJ_3 -41
 
-static void rcar_gen3_thermal_calc_coefs(struct rcar_gen3_thermal_tsc *tsc,
-					 int *ptat, const int *thcode,
+static void rcar_gen3_thermal_calc_coefs(struct rcar_gen3_thermal_priv *priv,
+					 struct rcar_gen3_thermal_tsc *tsc,
 					 int ths_tj_1)
 {
 	/* TODO: Find documentation and document constant calculation formula */
@@ -143,16 +135,16 @@ static void rcar_gen3_thermal_calc_coefs(struct rcar_gen3_thermal_tsc *tsc,
 	 * Division is not scaled in BSP and if scaled it might overflow
 	 * the dividend (4095 * 4095 << 14 > INT_MAX) so keep it unscaled
 	 */
-	tsc->tj_t = (FIXPT_INT((ptat[1] - ptat[2]) * (ths_tj_1 - TJ_3))
-		     / (ptat[0] - ptat[2])) + FIXPT_INT(TJ_3);
+	tsc->tj_t = (FIXPT_INT((priv->ptat[1] - priv->ptat[2]) * (ths_tj_1 - TJ_3))
+		     / (priv->ptat[0] - priv->ptat[2])) + FIXPT_INT(TJ_3);
 
-	tsc->coef.a1 = FIXPT_DIV(FIXPT_INT(thcode[1] - thcode[2]),
+	tsc->coef.a1 = FIXPT_DIV(FIXPT_INT(tsc->thcode[1] - tsc->thcode[2]),
 				 tsc->tj_t - FIXPT_INT(TJ_3));
-	tsc->coef.b1 = FIXPT_INT(thcode[2]) - tsc->coef.a1 * TJ_3;
+	tsc->coef.b1 = FIXPT_INT(tsc->thcode[2]) - tsc->coef.a1 * TJ_3;
 
-	tsc->coef.a2 = FIXPT_DIV(FIXPT_INT(thcode[1] - thcode[0]),
+	tsc->coef.a2 = FIXPT_DIV(FIXPT_INT(tsc->thcode[1] - tsc->thcode[0]),
 				 tsc->tj_t - FIXPT_INT(ths_tj_1));
-	tsc->coef.b2 = FIXPT_INT(thcode[0]) - tsc->coef.a2 * ths_tj_1;
+	tsc->coef.b2 = FIXPT_INT(tsc->thcode[0]) - tsc->coef.a2 * ths_tj_1;
 }
 
 static int rcar_gen3_thermal_round(int temp)
@@ -174,7 +166,7 @@ static int rcar_gen3_thermal_get_temp(void *devdata, int *temp)
 	/* Read register and convert to mili Celsius */
 	reg = rcar_gen3_thermal_read(tsc, REG_GEN3_TEMP) & CTEMP_MASK;
 
-	if (reg <= thcodes[tsc->id][1])
+	if (reg <= tsc->thcode[1])
 		val = FIXPT_DIV(FIXPT_INT(reg) - tsc->coef.b1,
 				tsc->coef.a1);
 	else
@@ -401,9 +393,15 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
 	unsigned int i;
 	int ret;
 
-	/* default values if FUSEs are missing */
+	/* Default THCODE values in case FUSEs are not set. */
 	/* TODO: Read values from hardware on supported platforms */
-	int ptat[3] = { 2631, 1509, 435 };
+	static const int thcodes[TSC_MAX_NUM][3] = {
+		{ 3397, 2800, 2221 },
+		{ 3393, 2795, 2216 },
+		{ 3389, 2805, 2237 },
+		{ 3415, 2694, 2195 },
+		{ 3356, 2724, 2244 },
+	};
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
@@ -413,6 +411,10 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
 	if (soc_device_match(r8a7795es1))
 		priv->thermal_init = rcar_gen3_thermal_init_r8a7795es1;
 
+	priv->ptat[0] = 2631;
+	priv->ptat[1] = 1509;
+	priv->ptat[2] = 435;
+
 	platform_set_drvdata(pdev, priv);
 
 	if (rcar_gen3_thermal_request_irqs(priv, pdev))
@@ -439,7 +441,10 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
 			ret = PTR_ERR(tsc->base);
 			goto error_unregister;
 		}
-		tsc->id = i;
+
+		tsc->thcode[0] = thcodes[i][0];
+		tsc->thcode[1] = thcodes[i][1];
+		tsc->thcode[2] = thcodes[i][2];
 
 		priv->tscs[i] = tsc;
 
@@ -453,7 +458,7 @@ static int rcar_gen3_thermal_probe(struct platform_device *pdev)
 		tsc->zone = zone;
 
 		priv->thermal_init(tsc);
-		rcar_gen3_thermal_calc_coefs(tsc, ptat, thcodes[i], *ths_tj_1);
+		rcar_gen3_thermal_calc_coefs(priv, tsc, *ths_tj_1);
 
 		tsc->zone->tzp->no_hwmon = false;
 		ret = thermal_add_hwmon_sysfs(tsc->zone);