[PATCH v4 3/7] drivers/thermal/exynos: improve sanitize_temp_error

[Mateusz Majewski]

There are two minor issues regarding this function.

One is that it attempts to calculate the second calibration value even
if 1-point trimming is being used; in this case, the calculated value is
probably not useful and is never used anyway. Changing this also
requires a minor reordering in Exynos5433 initialization function, so
that we know which type of trimming is used before we call
sanitize_temp_error.

The second issue is that the function is not very consistent when it
comes to the use of Exynos7-specific parameters. This seems to not be an
issue in practice, in part because some of these issues are related to
the mentioned calculation of the second calibration value. However,
fixing this makes the code a bit less confusing, and will be required
for Exynos850 which has 9-bit temperature values and uses 2-point
trimming.

Signed-off-by: Mateusz Majewski <m.majewski2 at samsung.com>
---
v3 -> v4: further reworked to avoid SoC-specific code, instead using
  SoC-specific parameters inside of exynos_tmu_data (probably different
  enough to drop R-b).
v1 -> v2: reworked to change shift instead of only mask and to also fix
  the 2-point trimming issue.

 drivers/thermal/samsung/exynos_tmu.c | 40 ++++++++++++++++++----------
 1 file changed, 26 insertions(+), 14 deletions(-)

diff --git a/drivers/thermal/samsung/exynos_tmu.c b/drivers/thermal/samsung/exynos_tmu.c
index b68e9755c933..8b1014915c31 100644
--- a/drivers/thermal/samsung/exynos_tmu.c
+++ b/drivers/thermal/samsung/exynos_tmu.c
@@ -111,6 +111,7 @@
 #define EXYNOS7_TMU_REG_EMUL_CON		0x160
 
 #define EXYNOS7_TMU_TEMP_MASK			0x1ff
+#define EXYNOS7_TMU_TEMP_SHIFT			9
 #define EXYNOS7_PD_DET_EN_SHIFT			23
 #define EXYNOS7_TMU_INTEN_RISE0_SHIFT		0
 #define EXYNOS7_EMUL_DATA_SHIFT			7
@@ -152,6 +153,8 @@ enum soc_type {
  * @max_efuse_value: maximum valid trimming data
  * @temp_error1: fused value of the first point trim.
  * @temp_error2: fused value of the second point trim.
+ * @temp_mask: SoC specific temperature mask
+ * @temp_85_shift: SoC specific address shift
  * @gain: gain of amplifier in the positive-TC generator block
  *	0 < gain <= 15
  * @reference_voltage: reference voltage of amplifier
@@ -182,6 +185,8 @@ struct exynos_tmu_data {
 	u32 min_efuse_value;
 	u32 max_efuse_value;
 	u16 temp_error1, temp_error2;
+	u16 temp_mask;
+	int temp_85_shift;
 	u8 gain;
 	u8 reference_voltage;
 	struct thermal_zone_device *tzd;
@@ -229,25 +234,26 @@ static int code_to_temp(struct exynos_tmu_data *data, u16 temp_code)
 		EXYNOS_FIRST_POINT_TRIM;
 }
 
+/*
+ * Sanitize sensor calibration values, according to minimum and maximum
+ * values defined for each SoC.
+ */
 static void sanitize_temp_error(struct exynos_tmu_data *data, u32 trim_info)
 {
-	u16 tmu_temp_mask =
-		(data->soc == SOC_ARCH_EXYNOS7) ? EXYNOS7_TMU_TEMP_MASK
-						: EXYNOS_TMU_TEMP_MASK;
-
-	data->temp_error1 = trim_info & tmu_temp_mask;
-	data->temp_error2 = ((trim_info >> EXYNOS_TRIMINFO_85_SHIFT) &
-				EXYNOS_TMU_TEMP_MASK);
-
+	data->temp_error1 = trim_info & data->temp_mask;
 	if (!data->temp_error1 ||
 	    (data->min_efuse_value > data->temp_error1) ||
 	    (data->temp_error1 > data->max_efuse_value))
-		data->temp_error1 = data->efuse_value & EXYNOS_TMU_TEMP_MASK;
+		data->temp_error1 = data->efuse_value & data->temp_mask;
 
-	if (!data->temp_error2)
-		data->temp_error2 =
-			(data->efuse_value >> EXYNOS_TRIMINFO_85_SHIFT) &
-			EXYNOS_TMU_TEMP_MASK;
+	if (data->cal_type == TYPE_TWO_POINT_TRIMMING) {
+		data->temp_error2 = (trim_info >> data->temp_85_shift) &
+				    data->temp_mask;
+		if (!data->temp_error2)
+			data->temp_error2 =
+				(data->efuse_value >> data->temp_85_shift) &
+				data->temp_mask;
+	}
 }
 
 static int exynos_tmu_initialize(struct platform_device *pdev)
@@ -510,7 +516,6 @@ static void exynos5433_tmu_initialize(struct platform_device *pdev)
 	int sensor_id, cal_type;
 
 	trim_info = readl(data->base + EXYNOS_TMU_REG_TRIMINFO);
-	sanitize_temp_error(data, trim_info);
 
 	/* Read the temperature sensor id */
 	sensor_id = (trim_info & EXYNOS5433_TRIMINFO_SENSOR_ID_MASK)
@@ -532,6 +537,8 @@ static void exynos5433_tmu_initialize(struct platform_device *pdev)
 		break;
 	}
 
+	sanitize_temp_error(data, trim_info);
+
 	dev_info(&pdev->dev, "Calibration type is %d-point calibration\n",
 			cal_type ?  2 : 1);
 }
@@ -876,6 +883,7 @@ static int exynos_map_dt_data(struct platform_device *pdev)
 		data->tmu_control = exynos4210_tmu_control;
 		data->tmu_read = exynos4210_tmu_read;
 		data->tmu_clear_irqs = exynos4210_tmu_clear_irqs;
+		data->temp_mask = EXYNOS_TMU_TEMP_MASK;
 		data->gain = 15;
 		data->reference_voltage = 7;
 		data->efuse_value = 55;
@@ -898,6 +906,7 @@ static int exynos_map_dt_data(struct platform_device *pdev)
 		data->tmu_read = exynos4412_tmu_read;
 		data->tmu_set_emulation = exynos4412_tmu_set_emulation;
 		data->tmu_clear_irqs = exynos4210_tmu_clear_irqs;
+		data->temp_mask = EXYNOS_TMU_TEMP_MASK;
 		data->gain = 8;
 		data->reference_voltage = 16;
 		data->efuse_value = 55;
@@ -919,6 +928,8 @@ static int exynos_map_dt_data(struct platform_device *pdev)
 		data->tmu_read = exynos4412_tmu_read;
 		data->tmu_set_emulation = exynos4412_tmu_set_emulation;
 		data->tmu_clear_irqs = exynos4210_tmu_clear_irqs;
+		data->temp_mask = EXYNOS_TMU_TEMP_MASK;
+		data->temp_85_shift = EXYNOS_TRIMINFO_85_SHIFT;
 		data->gain = 8;
 		if (res.start == EXYNOS5433_G3D_BASE)
 			data->reference_voltage = 23;
@@ -939,6 +950,7 @@ static int exynos_map_dt_data(struct platform_device *pdev)
 		data->tmu_read = exynos7_tmu_read;
 		data->tmu_set_emulation = exynos4412_tmu_set_emulation;
 		data->tmu_clear_irqs = exynos4210_tmu_clear_irqs;
+		data->temp_mask = EXYNOS7_TMU_TEMP_MASK;
 		data->gain = 9;
 		data->reference_voltage = 17;
 		data->efuse_value = 75;
-- 
2.45.2